CN100551603C - An Electromagnetic Composite Field Fusion Pole Surfacing Method, Equipment and Its Extended Application - Google Patents

Abstract

The invention discloses an electromagnetic composite field surfacing welding method, equipment and expanded application thereof, which is a method for electromagnetic composite field control powder core welding wire droplet jet transition melting electrode gas shielded surfacing welding method. The surfacing welding equipment of the present invention is provided with an excitation power supply, excitation equipment, auxiliary electric field equipment and a water cooling system; the excitation equipment is provided with an electromagnetic stirring excitation coil and an electromagnetic heat treatment excitation coil; the auxiliary electric field equipment is a pair of movable positive and negative auxiliary conductive electrodes. Through the combined action of electromagnetic stirring, electromagnetic heat treatment, auxiliary electric field and welding torch, it realizes the process of high-efficiency, high-quality and low-cost surfacing alloy materials; it breaks through the limitations of traditional surfacing technology, reduces the cost of functional material surfacing and the harsh Process conditions prolong the service life, solve the dependence of high-efficiency surfacing technology on helium-rich shielding gas, improve the surfacing control means, and realize the effective matching of high toughness and high toughness and plasticity of surfacing functions. In the field of surface engineering Opened up a new scope of application.

Description

An Electromagnetic Composite Field Fusion Pole Surfacing Method, Equipment and Its Extended Application

technical field

The invention relates to the field of surface engineering surfacing welding, in particular to an electromagnetic composite field controlled powder core welding wire droplet jet transition melting electrode gas shielded surfacing welding method, equipment and expanded applications thereof.

Background technique

The metal gas shielded welding method characterized by the droplet rotating jet transfer is considered to be one of the efficient welding techniques. The similar technology widely used at home and abroad is a mixed gas melting electrode welding technology (such as TIME, RAPID MELT, LINFAST, etc.) with high helium as the main component. For my country, helium resources are relatively scarce and the cost is high. ; At the same time, the protective gas formula also has international intellectual property rights, making the use of its technology and equipment more expensive. At present, domestic researchers have adopted the method of external magnetic field welding instead of helium to realize the stable transition of molten droplets, and published three patent applications in this area: one is magnetically controlled high cladding rate molten electrode mixed gas shielded welding (MAG ) method and special equipment (application number 02116241.7), which adopts a single air-core coil fixed on the welding torch, constant excitation current, generates a constant magnetic field, can partially control the welding arc and droplet transfer, and is only suitable for medium welding current (welding current less than 600A ), shallow grooves, and welding of some ferrous metals of ordinary steel. One is the magnetically controlled high-current MAG welding method and equipment (application number 200410086897.0) that can be used for deep groove welding. It only improves the hollow excitation coil on the basis of the former. Welding of workpieces in the form of deep groove joints. The third item is the patent application I put forward: a magnetron melting pole welding method and its extended application and general equipment (application number 200510019637.6).

The above three patent applications or authorizations are all aimed at the field of welding engineering technology, but not for the field of surfacing welding which belongs to surface engineering. Although surfacing welding belongs to the category of welding and has the general characteristics of ordinary welding technology, surfacing welding is different from conventional welding technology to a certain extent. Its distinctive feature is not to connect parts (parts) like ordinary welding methods, but to use welding (connection) method (that is, the surfacing layer and the base metal have a typical metallurgical bond), select or design the relevant surfacing alloy according to the specific service requirements of the workpiece, and clad the surface of the material or workpiece (part) with certain properties. The functional layer enables the material or the surface of the workpiece to have special functions (such as high strength, high toughness, wear resistance, oxidation resistance, etc.) to meet the needs of the specific working environment of the component. For example, the research on high-efficiency mixed gas shielded melting electrode (MAG) welding technology (droplet jet transition form) focuses on obtaining high cladding rate and high fusion ratio (high dilution rate), and if the research on high-efficiency MAG surfacing welding technology A reasonable matching control of high cladding rate and low fusion ratio (low dilution rate) is required. Therefore, surfacing technology has its own special requirements.

The new surfacing technology mainly considers three factors: deposition speed, dilution rate and surfacing layer performance, that is, lower base metal dilution rate, higher cladding rate and excellent surfacing layer performance. For the first two factors "deposition speed" and "dilution rate", the following methods are generally used to reduce the dilution rate during arc source surfacing: (1) reduce the heat input of the arc to the base metal; (2) reduce The concentrated heating degree of the arc on the base metal; (3) reduce the excavation effect of the arc on the base metal, etc. On the other hand, in order to increase the deposition rate, the following measures need to be taken: (1) increase the heat input of the arc; (2) increase the degree of arc concentration; (3) increase the speed of wire feeding or powder feeding (surfacing speed). It can be seen that high deposition rate and low dilution rate often restrict each other, and it is necessary to effectively coordinate the contradictory relationship between the two, so that high deposition rate and low dilution rate can be organically unified. The core content of the third element of surfacing technology, "surfacing layer performance", is to obtain a high-quality surfacing layer. However, for example, when surfacing high-temperature high-strength alloy materials on ordinary materials, cracking of the surfacing layer and peeling off of the surfacing layer and the substrate are often prone to occur between different surfacing layers (between the surfacing interface layers), which involves Solved the problem of toughening of high-temperature high-strength hard alloy surfacing layer. Moreover, the surfacing layer with high wear resistance (high hardness) generally has low toughness, and the surfacing process or heat treatment conditions required by it are relatively strict and complicated, and are often prone to defects, and even cause surfacing The functional layer fails. Therefore, the new surfacing welding technology needs to coordinate the contradictory relationship between the toughness and ductility of the surfacing functional layer of the material.

At present, manual arc surfacing and flame surfacing are the most commonly used surfacing processes due to the advantages of the lowest cost, simplicity and flexibility, and large adaptability, but they have disadvantages such as low automation, high labor intensity, and difficult control of surfacing quality. Its application is limited to a certain extent. The research of modern surfacing technology focuses on plasma surfacing, submerged arc (electroslag) surfacing, gas shielded surfacing, laser cladding and friction stir surfacing, etc. The selection of surfacing heat source mainly focuses on arc heat source. . Relatively speaking, high-efficiency gas shielded surfacing welding technology has become a new direction for the development of surfacing welding technology because of its high production efficiency, good quality, low cost, easy automation process, and the ability to give full play to the advantages of surfacing welding robots. one. Therefore, further improvement and development are needed to truly realize a new surfacing technology with high efficiency, high quality and low cost in a complete sense.

Contents of the invention

In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide an electromagnetic composite field control method and general-purpose equipment for high-efficiency, low-cost, high-stability and high-quality surfacing welding functions, so as to break through The limitation of traditional surfacing technology is the long-term constraints of high preparation cost, harsh process conditions and (especially) short service life of functional material surfacing, so as to solve the dependence of new high-efficiency surfacing technology on helium-rich multi-component shielding gas, Improve the surfacing welding control means, realize the effective matching of high hardness and high toughness and plasticity of the surfacing welding functional layer, break the use limitation of high-efficiency welding technology, and thus open up a new application range in the field of surface engineering.

The technical solution adopted by the present invention to solve its technical problems is as follows:

1. The electromagnetic composite field surfacing method provided by the present invention is an electromagnetic composite field control powder cored wire droplet jet transition melting electrode gas shielded surfacing method. The specific method is: on the surfacing workpiece, use a pair of electromagnetic stirring excitation Coil and electromagnetic heat treatment excitation coil, the electromagnetic stirring excitation coil is coaxial with the welding torch; the excitation current is provided by the excitation power supply to generate electromagnetic stirring and electromagnetic heat treatment plus a longitudinal magnetic field; two movable auxiliary electric field electrodes are applied on the surfacing weld, Auxiliary electric field is generated; the welding power supply provides surfacing and auxiliary electric field current, and an auxiliary electric field electrode is of the same polarity as the conductive tip of the torch; the electromagnetic composite field realizes electromagnetic composite field control of high cladding melting electrode gas shielded surfacing welding on the welding workpiece.

2. The electromagnetic composite field surfacing welding method provided by the present invention, the electromagnetic stirring excitation coil and the electromagnetic heat treatment excitation coil are connected with different frequencies, unequal strengths, and time-varying excitation currents, and utilize a magnetic field matched by a higher frequency and a weaker intensity Electromagnetic stirring is performed to control the welding arc, the droplet shedding at the end of the welding wire and the stability of the liquid stream during the transition of the rotating jet, and it has the effect of auxiliary induction heating to promote the melting of the welding wire and the formation of droplets, and can make the welding pool melt The body is fully stirred; and the use of a magnetic field with a lower frequency and a larger intensity for electromagnetic heat treatment can change the crystallization status of the molten pool metal, change the solidification process and temperature distribution (the structure and phase structure will also change), and promote the welding seam Grain refinement, reducing chemical inhomogeneity, reducing the sensitivity of pores, is conducive to improving toughness and plasticity, and forming a high-quality surfacing layer; realize the electromagnetic composite field surfacing process that meets the surfacing requirements for the surfacing workpiece;

Alternatively, the electromagnetic stirring excitation coil and the electromagnetic heat treatment excitation coil are connected to the excitation power supply at the same time to generate a time-varying longitudinal electromagnetic field with the same frequency, same phase, and the same intensity or a constant longitudinal electromagnetic field with uniform intensity, and realize an electromagnetic composite field that meets the requirements of the surfacing process for the workpiece Surfacing process;

Alternatively, the electromagnetic stirring excitation coil and the electromagnetic heat treatment excitation coil are used separately, and an excitation power supply is connected to generate a time-varying longitudinal electromagnetic field or a constant longitudinal electromagnetic field of uniform strength for separate electromagnetic stirring or electromagnetic heat treatment;

Including the following process conditions: surfacing welding current 80-800A, wire feeding speed 0-50m/min, wire diameter 0.8-6mm, shielding gas flow 1-50L/min, welding voltage 1-60V, welding speed 0.01-6m /min, excitation current 0~60A, excitation frequency 0~100Hz, auxiliary field current 0~300A.

3. The electromagnetic compound field control melter gas shielded surfacing equipment provided by the present invention is provided with excitation power supply, excitation equipment, auxiliary electric field equipment and water cooling system; the excitation equipment is electromagnetic stirring excitation coil and electromagnetic heat treatment excitation coil, electromagnetic stirring excitation coil And the excitation coil for electromagnetic heat treatment provides excitation current through the excitation power supply; the excitation power supply adopts a power supply that can generate time-varying excitation current or constant current excitation current with multiple frequencies and different intensities; the excitation coil for electromagnetic stirring and the excitation coil for electromagnetic heat treatment are both axisymmetric cylinders The coil structure is respectively arranged on two brackets; the electromagnetic stirring excitation coil is fixed on the welding torch and is coaxial with the welding torch; a clamping and locking mechanism connected with the welding torch is provided at the end of the bracket of the electromagnetic stirring excitation coil , which fixes the excitation coil on the nozzle of the welding torch, so that the excitation coil and the workpiece have a certain distance of free adjustment; the distance between the welding torch and the electromagnetic heat treatment excitation coil can be adjusted, and the bracket is equipped with a water cooling system;

The auxiliary electric field equipment is mainly composed of two movable auxiliary electric field electrodes, one is connected to the negative pole and the other is connected to the positive pole, and the current is supplied by the welding power supply or other independent power supply; one auxiliary electric field electrode has the same polarity as the welding torch. The auxiliary electric field electrode can be replaced by other types of surfacing welding torches to form a composite welding torch surfacing welding method.

The structure and method of use of the auxiliary conductive (field) equipment are as follows: a pair of movable conductive electrodes are used, with the welding direction as the front (front), and the unmelted (non-surfacing) metal part in the front of the molten pool, according to the surfacing The polarity selection or use of the welding torch (such as positive or reverse polarity) determines that the conductive electrode of the same polarity is kept at a certain distance from the molten pool, moves with the torch, or is fixed (when the workpiece moves, the torch does not move) In the case of surfacing); the conductive electrode of the other polarity is located at the back of the solidified low-temperature metal of the surfacing weld. In this case, the auxiliary conductive field is consistent with the surfacing weld (coincidence), which is called the longitudinal auxiliary electric field. Auxiliary conduction (field) plays a comprehensive role in preheating, surfacing main current shunting and post heat treatment in the surfacing process.

4. In the electromagnetic composite field melting pole gas shielded surfacing equipment provided by the present invention, the electromagnetic stirring excitation coil and the electromagnetic heat treatment excitation coil are respectively provided with a conductive core; In the excitation coil, its position in the excitation coil can be adjusted freely until it is completely removed from the coil; the shape of the end of the magnetic core is funnel-shaped, straight barrel-shaped, conical or curved; the shape of the lower end surface of the magnetic core shrinks , so that the magnetic lines of force can be more concentrated on the surfacing weld.

5. The electromagnetic compound field melting pole gas shielded surfacing equipment provided by the present invention, the electromagnetic heat treatment excitation coil is rigidly connected with the excitation coil and the welding torch through an adjustable fixed arm, and the adjustable fixed arm can change the welding torch The distance from the excitation coil realizes a reasonable application method of electromagnetic composite field surfacing welding at different welding speeds;

Alternatively, the electromagnetic stirring excitation coil is directly integrated with the torch nozzle without passing through the bracket, and the outer wall of the torch nozzle is kept insulated from the coil turns by using insulating materials, and cooled by the water cooling system built inside the torch nozzle .

6. In the electromagnetic compound field control melting pole gas shielded surfacing equipment provided by the present invention, the water cooling system in the bracket of the electromagnetic stirring excitation coil and the bracket of the electromagnetic heat treatment excitation coil adopts a cover plate type rectangular pulse-shaped condensate flow mode, and the two brackets There are water flow grooves and two drainage flow partitions arranged in a staggered manner, and the two drainage flow partitions are respectively connected with the outer baffles on both sides of the water flow groove;

The water cooling system in the welding torch nozzle can adopt a cover-type spiral condensed water flow pattern, and its structure is: a spiral threaded water flow groove is designed in the welding torch nozzle wall, and the welding torch nozzle baffle forms a welding torch The all-round condensed water channel in the nozzle makes the condensed water flow spirally around the torch nozzle and reach the end of the torch nozzle without deformation of the torch.

The electromagnetic compound field surfacing welding method provided by the present invention and the purposes of surfacing welding equipment in the following aspects:

It is used for high cladding rate (high speed) gas shielded surfacing welding, or ordinary gas shielded welding, or non-gas shielded welding, or plasma surfacing, or laser surfacing;

Used for surfacing welding of the following materials (or alloy powder): medium and high carbon wear-resistant alloy (cast iron), high temperature hard alloy, stainless steel and its alloy and other metals and their alloys (or alloy powder);

For single-layer surfacing welding, multi-layer surfacing welding of a single material, or single-layer surfacing welding, multi-layer surfacing welding of multiple materials, or multi-layer surfacing welding of gradient materials;

The electromagnetic composite field surfacing welding method and surfacing welding equipment provided by the present invention are used in the following welding aspects:

Used for welding in the following materials: low carbon steel, alloy steel, special steel, stainless steel, copper and its alloys, aluminum and its alloys, magnesium and its alloys, titanium and its alloys and other ferrous and non-ferrous metals and their alloys;

For welding solid wire, flux cored wire and powder cored wire;

It is used for butt joint, lap joint, fillet joint and all-position welding for various welding joint forms;

It is used in the field of single gas shielded melting electrode welding, or binary or multi-component mixed gas shielded melting electrode welding;

For high cladding rate (high speed) MIG welding, or ordinary MIG welding, or ordinary MIG welding, or plasma welding, or laser welding, or hybrid welding technology (such as TIG+MIG) ;

Compared with the prior art, the present invention has the following remarkable effects:

One. Compared with the traditional gas shielded welding process, it breaks through the limitation of the welding current in the form of stable jet droplet transfer. Compared with the traditional flux-cored wire or powder-cored wire gas-shielded welding process, it is beneficial to realize stable droplet rotating jet transition, good weld shape and low cost.

Second. Compared with foreign high-efficiency welding technologies (such as TIME welding technology, etc.), it solves the dependence on helium-rich multi-component shielding gas, and uses helium-free shielding gas (such as carbon dioxide gas) to significantly reduce welding costs.

Third. Compared with the magnetic control MAG welding technology, the means and methods of adding an external electromagnetic compound field to control the welding process are added, which improves the flexibility of the magnetic control welding process parameters and enhances the applicability of high-efficiency and low-cost magnetic control welding technology .

Fourthly, it breaks the use limitation of magnetic control welding technology and opens up a new space for use.

Fifth. Compared with other conventional surfacing technologies, the innovative method of integrating relevant technologies and research results to stably realize high-efficiency gas-shielded surfacing welding in an electromagnetic composite field with a coordinated and matched high deposition rate and low dilution rate is to solve the problem of surfacing welding. Dilemma provides a new approach.

Sixth. Compared with other magnetron surfacing technologies (such as plasma surfacing), the new technology of high-efficiency gas shielded surfacing welding in electromagnetic composite field is used to realize high-quality surfacing layer with high hardness and toughness organically and uniformly at low cost, reducing It has met its strict requirements on surfacing welding technology and heat treatment process, and realized the technological innovation of surfacing welding functional layer.

Seventh. Compared with the conventional surfacing or welding process, when using flux-cored welding wire or powder-cored welding wire for surfacing or welding, or when using carbon dioxide gas shielded surfacing or welding, the stability of droplet transfer is improved, spatter is reduced, and welding Good seam formation and improved quality.

Eighth. It has a wide range of applications, requires simple equipment, and is easy to promote and use. It promotes the development of green, sustainable and high-tech processes and equipment in the field of advanced surfacing technology that meet the needs of circular economy, and improves and enriches the basic theory and technical practice capabilities of surfacing surface engineering.

The invention develops new and advanced surfacing welding technology in the field of surface engineering, which includes: breaking through the two contradictory limitations of high cladding rate and low dilution rate, and realizing the effective coordination and coordination of high hardness and high toughness surfacing layer performance. Reasonable and unified, reducing the harsh requirements on the surfacing process and post-processing links, using the perfect electromagnetic composite field technology to successfully overcome the limitations of the use of a single external magnetic field, so that the sustainable and advanced surfacing technology that meets the needs of circular economy and Contributed to the development and practical use of equipment. The invention has broad application value and development prospects in the fields of mold manufacturing and remanufacturing, mechanical equipment recycling and utilization, key component repair, material preparation, resource recycling, and green recycling manufacturing and equipment. The invention realizes a high-efficiency, low-cost, high-quality, high-stability, multi-applicability, multi-mode comprehensive and easy-to-control surfacing welding process.

In a word, the present invention realizes the process of high-efficiency, high-quality, low-cost, and high-stability surfacing welding alloy materials or gradient materials through the composite action of electromagnetic stirring, electromagnetic heat treatment, auxiliary electric field and welding torch; it breaks through the limitations of traditional surfacing welding technology High preparation costs, harsh process conditions, and short service life of high-performance material surfacing are constrained by long-term constraints, solving the dependence of new high-efficiency surfacing technology on helium-rich multi-element shielding gas, improving surfacing control methods, and realizing surfacing The effective matching of high rigidity and high toughness and plasticity of the functional layer opens up new application areas in the field of surface engineering.

Description of drawings

Fig. 1 is a schematic diagram of welding method and equipment of the present invention;

Figure 2 is a schematic diagram of the structure of the electromagnetic stirring and electromagnetic heat treatment excitation coil support water cooling system and the flow of cooling water;

Figure 3 is a schematic diagram of the structure of the surfacing welding torch nozzle water cooling system and the flow of cooling water.

In the figure, 1. bracket; 2. welding torch nozzle; 3. welding torch conductive tip; 4. magnetic core; 5. welding and auxiliary electric field power supply; 6. welding wire; 7. workpiece; 8. electromagnetic stirring excitation coil; 9 .Electromagnetic heat treatment excitation coil; 10. Excitation power supply; 11. Magnetic core; 12. Bracket; 13. Auxiliary electric field electrode; 14. Auxiliary electric field electrode; ; 18. Water flow partition in the bracket; 19. Welding torch nozzle baffle; 20. Welding torch nozzle wall; 21. Threaded water flow groove.

Detailed ways

The present invention mainly includes a novel electromagnetic compound field control method and related universal equipment for electromagnetic compound field melting electrode gas shielded surfacing welding, and its application in other surfacing welding and welding technology.

The present invention will be further described below in conjunction with the embodiments and accompanying drawings.

1. Electromagnetic composite field control melting electrode surfacing method

The method is a helium-free high cladding melting electrode gas-shielded overlay welding method controlled by an electromagnetic composite field for the transition of a droplet jet flow. The specific method is as follows:

As shown in Figure 1: on the top of the surfacing workpiece 7, use a pair of electromagnetic stirring excitation coils 8 and electromagnetic heat treatment excitation coils 9 with magnetic cores 4 and 11 or without magnetic cores 4 and 11, and electromagnetic stirring excitation coils 8 is coaxial with the welding torch 3, through the same excitation power supply 10 or different excitation power supplies to provide excitation current respectively, to generate time-varying or constant, dual-frequency or single-frequency, same-intensity or different-intensity electromagnetic stirring and electromagnetic heat treatment Two external longitudinal magnetic fields; according to needs, simultaneously or differently apply movable auxiliary electrodes 13 and 14 in the longitudinal or transverse direction of the surfacing weld to generate an auxiliary electric field, the power supply 5 provides surfacing and auxiliary electric field current, and the auxiliary electric field electrode 13 Same polarity as welding torch contact tip 3 (or welding wire 6). The electromagnetic composite field comprehensively controls the process of welding arc, welding wire melting, droplet transfer, molten pool stirring, weld solidification, pre-weld preheating and post-weld heat treatment. With the cooperation, the electromagnetic compound field controls the helium-free high cladding melting electrode gas shielded surfacing process.

The electromagnetic composite field realizes comprehensive control of the surfacing process through six aspects: changing the type of magnetic field (time-varying magnetic field or constant magnetic field, single-frequency magnetic field or dual-frequency magnetic field), changing the frequency of the magnetic field (different frequencies), changing the intensity of the electromagnetic field ( Electric field and magnetic field with different strengths), change the application method of electromagnetic field (apply electric field longitudinally to the weld, or apply electric field transversely to the weld, or apply a magnetic field directly above the weld, or apply a magnetic field on both sides above the weld, or when the upper and lower sides of the workpiece are different Or applied simultaneously, or applied with a magnetic field that is not axial to the torch), and change the composition and ratio of the surfacing protective gas according to the surfacing object (Ar+20% CO ₂ , or CO ₂ , or Ar, or other multi-element gases Composition and ratio) and reasonable adjustment and matching with the surfacing welding process parameters (welding current, wire feeding speed, welding wire diameter, gas flow, welding speed, welding voltage, etc.).

1. The electromagnetic stirring excitation coil 8 and the electromagnetic heat treatment excitation coil 9 are paired with the excitation power supply 10. There are the following three methods:

(1) The electromagnetic stirring excitation coil 8 and the electromagnetic heat treatment excitation coil 9 can be simultaneously connected with dual-frequency, unequal intensity, and time-varying excitation currents produced by the excitation power supply 10. Under certain conditions, multiple process parameters and means can be used to flexibly, reliably and effectively control the temperature field of surfacing welding, the process of droplet formation, the movement state of the liquid stream, the degree of stirring of the molten pool, the solidification conditions of the weld seam and the surfacing welding Tissue generation to achieve the best coupling of temperature field, flow field and force field in magnetically controlled high-efficiency helium-free molten electrode surfacing, and finally form high-quality surfacing welds that meet the quality requirements of surfacing layers; at the same time, this multi-process parameter The reliable surfacing welding control method under controlled conditions can realize the surfacing process required by different specific materials, different surfacing materials and surfacing functional layers. The principle is: using a magnetic field with a higher frequency and a weaker intensity for electromagnetic stirring to control the welding arc, droplet shedding at the end of the welding wire and the stability of the liquid stream during the transition of the rotating jet, and has the function of auxiliary induction heating The effect promotes the melting of the welding wire and the formation of droplets, and can fully stir the weld pool melt. However, using a magnetic field with a lower frequency and a larger intensity for electromagnetic heat treatment can change the crystallization status of the molten pool metal, change the solidification process and temperature distribution (the structure and phase structure will also change), and promote the refinement of the weld grain , reduce chemical inhomogeneity, reduce the sensitivity of pores, help to improve toughness and plasticity, and form a high-quality surfacing layer; realize the electromagnetic composite field surfacing process that meets the surfacing welding requirements for the surfacing workpiece 7.

(2) The electromagnetic stirring excitation coil 8 and the electromagnetic heat treatment excitation coil 9 can be connected to the excitation power supply 10 at the same time to generate a time-varying longitudinal electromagnetic field of the same frequency, same phase, and same strength or a constant longitudinal electromagnetic field of uniform strength, so that the workpiece 7 can be surfacing. Electromagnetic composite field surfacing welding process required by the process.

(3) The electromagnetic stirring excitation coil 8 and the electromagnetic heat treatment excitation coil 9 can be used separately, and an excitation power supply 10 is applied to generate a time-varying longitudinal electromagnetic field or a constant longitudinal electromagnetic field of uniform intensity, and carry out independent electromagnetic stirring or electromagnetic heat treatment, The electromagnetic composite field surfacing process that meets the surfacing welding process requirements is realized on the workpiece 7 .

2. The auxiliary electric field electrode 13 and the auxiliary electric field electrode 14, as well as the conductive tip 3 of the surfacing welding torch and the power supply 5 are used in conjunction with the following five main methods:

(1) The auxiliary electric field electrode 13 and the welding wire 6 have the same polarity, and the electric current of different intensity is provided by the power supply 5 at the same time, the auxiliary electric field electrode 13 is weaker, and the surfacing welding current is stronger, and the auxiliary electric field electrode 14 and the auxiliary electric field electrode 13 and welding wire 6 are of different polarity, and its advantages are: under the same penetration condition of surfacing welding, the magnitude of the main surfacing welding current can be reduced, and the concentrated heating and excavation effect of the arc on the surfacing welding base material can be reduced, thereby effectively It is beneficial to reduce the dilution rate, reduce the droplet transition splash, increase the cladding rate, and form a good surfacing welding current circuit, and realize the electromagnetic composite field surfacing process that meets the surfacing welding process requirements for the workpiece 7.

(2) The auxiliary electric field streamline formed by the auxiliary electric field electrode 13 and the auxiliary electric field electrode 14 can coincide with the surfacing weld to form a longitudinal auxiliary electric field; The current lines of the electric field and the welding seam can produce intersection points at different positions in the molten pool or the front and back of the molten pool; the auxiliary electric field electrode 13 and the auxiliary electric field electrode 14 are used in conjunction with the power supply 5 to generate a pulsed time-varying current field, or a constant and uniform Intensity current field realizes the electromagnetic composite field surfacing process that meets the surfacing welding process requirements on the workpiece 7.

(3) The auxiliary electric field produced by the auxiliary electric field electrode 13 and the auxiliary electric field electrode 14 can be simultaneously or differently with the electromagnetic stirring magnetic field produced by the electromagnetic stirring excitation coil 8 and the electromagnetic heat treatment magnetic field produced by the electromagnetic heat treatment excitation coil 9 together, or in combination, Or it can play a role in the surfacing process alone, and realize the electromagnetic composite field surfacing process that meets the requirements of the surfacing process for the workpiece 7 .

(4) The auxiliary electric field electrode 13 and the auxiliary electric field electrode 14 can be replaced by other types of overlay welding torches (electrodes) to form a composite overlay welding mode, such as the auxiliary electric field electrode 13 is replaced by a TIG overlay welding torch (electrode) Instead, form a composite surfacing welding method in the form of a single molten pool of TIG+MAG/MIG or TIG+CO ₂ , and implement an electromagnetic composite field surfacing process that meets the requirements of the surfacing welding process for the workpiece 7 .

(5) Auxiliary electric field electrode 13 and auxiliary electric field electrode 14 can be various forms such as rod shape, bar shape; Can be sliding friction with workpiece, also can be rolling friction; Can be copper alloy material, also can be other materials. The electromagnetic composite field surfacing process that meets the surfacing welding process requirements is realized on the workpiece 7 .

The present invention adopts electromagnetic composite field fusion electrode gas protection surfacing welding process, which may include the following process conditions: surfacing welding welding current 80-800A, wire feeding speed 0-50m/min, welding wire straight length 0.8-6mm, shielding gas flow rate 1- 50L/min, welding voltage 1-60V, welding speed 0.01-6m/min, excitation current 0-60A, excitation frequency 0-100Hz, auxiliary electric field current 0-300A.

The above protective gas can be magnetron gas a, or magnetron gas b, or magnetron gas c, or magnetron gas d, or magnetron gas e, as follows:

Magnetron gas a is composed of 100% carbon dioxide, which is widely used in surfacing welding of high-carbon wear-resistant alloys;

The magnetron gas b consists of 100% argon. This gas is widely used in surfacing welding of various metals and alloy materials;

The magnetron gas c is composed of argon and carbon dioxide mixed, and its volume percentage is: 10-20% carbon dioxide + the remaining percentage of argon. This gas is widely used in surfacing welding of various metals and alloy materials;

The magnetron gas d is mainly composed of argon gas mixed with ternary gas, and its volume percentage is: 80-90% argon + 1-2% oxygen + carbon dioxide in the remaining percentage. This gas is widely used in surfacing welding of various metals and alloy materials;

The magnetron gas e is composed of the mixture of argon and nitrogen, and its volume percentage is: 5-25% nitrogen + the remaining percentage of argon. This type of gas is typically used for surfacing of metals and their alloys that are inert to the gas, such as copper and its alloys.

The above-mentioned protective gas can also use other common protective gas components or binary or multi-component protective gases added with helium.

The above-mentioned surfacing welding wire can use solid welding wire, or flux-cored welding wire, or metal powder-cored welding wire.

In the electromagnetic composite field surfacing welding method provided by the present invention, the powder-cored welding wire can use welding wire a, or welding wire b, or welding wire c, and the specific formula is as follows:

The welding wire a is composed of C, Cr, Ni, Mo, Mn, Si, N alloy powders, and the metal powder core is composed of (Wt%): C 0.28～0.40%, Cr12.1～14.2%, Ni2.9～5.2 %, Mo 0.78～0.91%, Mn 0.65～1.61, Si 0.16～0.96%, S≤0.01%, P≤0.025%, N0.02～0.04%, rare earth 0.01～3.2%. The protective gas composed of argon and nitrogen mixture is used, and its volume percentage is: 10-30% nitrogen + remaining percentage argon, which has the function of in-situ composite nitride surfacing;

The welding wire b is composed of C, Cr, Ni, Si, B, Mn alloy powders to form a metal powder core, and its composition range is (Wt%): C0.08～0.17%, Cr10.2～18.3%, Ni3.4～5.8% , Si0.38-0.81%, B0.14-0.34%, Mn0.68-1.61%. The protective gas is composed of a mixture of carbon dioxide and argon, and its volume percentage is: 10-20% carbon dioxide + the remaining percentage of argon, which has the function of high-efficiency carbon dioxide mixed gas shielded surfacing;

The welding wire c is composed of C, Cr, W, Mo, V, Nb alloy powder, and its composition range is (W t%): C 0.4～0.9%, Cr16.2～26.4%, W2.9～6.2% , Mo 0.38～3.41%, V0.24～0.38%, Nb2.3～5.8%, rare earth 0.01～4.6%. The shielding gas adopts 100% argon, which has the function of high-efficiency surfacing welding of hard alloy materials.

2. General-purpose equipment for gas-shielded surfacing welding controlled by electromagnetic composite field

This equipment is a general-purpose equipment for helium-free high-efficiency melter gas shielded welding controlled by electromagnetic compound field, as shown in Figure 1: it is equipped with excitation power supply, excitation equipment, auxiliary electric field equipment and water cooling system. The excitation coil 9 is treated with electromagnetic heat.

1. Electromagnetic stirring excitation coil 8 and electromagnetic heat treatment excitation coil 9:

According to actual welding needs, the excitation coils can be used simultaneously or separately, their distance is adjustable, and the electromagnetic stirring excitation coil 8 is coaxial with the welding torch 2 . The supporting excitation power supply 10 adopts four-channel digital inverter power supply or two sets of independent digital inverter power supply or ordinary power supply, which can generate stepless and continuously adjustable constant excitation current and time-varying excitation current (such as intermittent alternating bidirectional pulse current with adjustable frequency, duty cycle, and amplitude).

The structure, connection relationship and effect of the above-mentioned excitation coil are illustrated below in conjunction with the accompanying drawings:

As shown in Figure 1: a pair of electromagnetic stirring excitation coil 8 and electromagnetic heat treatment excitation coil 9 are respectively located above the workpiece 7, taking the positive direction of surfacing as a reference system, the electromagnetic stirring excitation coil 8 is in front, and the electromagnetic heat treatment excitation coil 9 is behind.

The electromagnetic stirring excitation coil 8 is fixed on the welding torch 3 and is coaxial with the welding torch 3 . The distance between the welding torch 3 and the electromagnetic heat treatment excitation coil 9 can be adjusted freely. According to the size of the welding speed, the relative position of the two is adjusted so that the electromagnetic heat treatment excitation coil 9 is located at the position of the solidified high-temperature solid metal immediately adjacent to the rear of the welding pool.

The above excitation coils are all axisymmetric cylindrical coil structures, with a magnetic core 4 and a magnetic core 11 or without a magnetic core 4, or the magnetic core 11 is a full section of the center, and the brackets 1 and 12 are equipped with a water cooling system ; These excitation coils move synchronously with the welding torch 3 at the same speed, or remain still (in the case of the workpiece 7 moving).

The magnetically permeable core 4 and the magnetically permeable core 11 are movably installed in the electromagnetic stirring excitation coil 8 and the electromagnetic heat treatment excitation coil 9 respectively, and their positions in the excitation coil can be freely adjusted until they are completely removed from the coil. The shapes of the ends of the magnetically permeable core 4 and the magnetically permeable core 11 can be designed into different shapes according to actual needs, such as funnel-shaped, straight-barrel-shaped, conical-shaped or curved-surface-shaped. The shapes of the permeable core 4 and the permeable core 11 used in the exciting coil 8 and the exciting coil 9 may be the same or different. The magnetically permeable core 4 and the magnetically permeable core 11 can be composed of a single rotating body as a whole, or composed of a plurality of bar-shaped independent bodies reasonably and organically distributed at different positions of the coil. At the same time, according to the actual needs of the surfacing process, the distance between the exciting coil, the magnetic core, the surfacing workpiece, the surfacing welding torch nozzle and the welding wire can be adjusted comprehensively. The position of the magnetic core 11 from the workpiece is much closer than the position of the magnetic core 4 from the workpiece, and a full-section iron core is used, and the shape of the lower end surface of the magnetic core 11 shrinks so that the magnetic force lines are more concentrated on the surfacing welding seam.

2. Several connections and water cooling methods of excitation coil 8, excitation coil 9 and welding torch 3:

(1) The electromagnetic stirring excitation coil 8 is fixedly connected with the welding torch 3 through the clamping and locking mechanism (omitted in the figure):

The end of the bracket 1 of the electromagnetic stirring excitation coil 8 is provided with a clamping and locking mechanism connected to the welding torch 3, which fixes the excitation coil on the welding torch nozzle 2, so that the excitation coil 8 and the workpiece 7 have a certain distance of freedom. Regulatory degree.

The water cooling system in the bracket 1 of the electromagnetic stirring excitation coil 8 adopts a cover-type rectangular pulse-shaped condensed water flow pattern, and its structure is shown in Figure 2: the bracket 1 is provided with a water flow groove 16 and two drainage partitions 18 arranged in a staggered manner. The two drain flow partitions 18 are respectively connected to the outer baffles 17 on both sides of the water flow groove 16, and they constitute an efficient and simple water cooling system in the support of the up and down recirculating condensed water flow pattern. The exquisite structure shown in Fig. 2, although the design and structure of the entire integrated space is simple, has a strong cooling effect and can fully meet the needs of high-current surfacing welding in the form of droplet jet transition. The arrows in the figure indicate the channel and direction of water flow.

The function of the water cooling system in the excitation coil coil is to protect the coil from heat dissipation and normal operation during high-current surfacing welding, and to achieve effective cooling protection in a limited geometric space.

(2) Electromagnetic stirring excitation coil 8 and welding torch nozzle 2 integrated direct connection:

In order to meet the good space accessibility of manual surfacing welding torch under medium and small surfacing welding current conditions or automatic surfacing welding torch under high welding current conditions, the support 1 can be omitted, and the electromagnetic stirring excitation coil 8 and the welding torch nozzle 2 can be directly connected. Integrate into one body, use insulating material to keep the outer wall of the torch nozzle 2 insulated from the turns of the coil, and cool it through the water cooling system built inside the torch nozzle 2, so that both the welding torch and the exciting coil are in good working condition.

The water cooling system in the welding torch nozzle 2 can adopt a cover-type spiral condensed water flow pattern, and its structure is shown in Figure 3: a spiral threaded water flow groove 20 is designed in the welding torch nozzle wall 21, combined with the welding torch nozzle block The plate 19 forms an omnidirectional condensed water passage in the torch nozzle, so that the condensed water flows in a spiral around the torch nozzle and reaches the end of the torch nozzle. This water cooling system has the advantages of compact space structure, simple design, and strong cooling effect, which can ensure that the welding torch 3 does not deform under high current conditions, and can fully meet the needs of high cladding and high current surfacing welding.

(3) Electromagnetic heat treatment excitation coil 9 is rigidly connected with excitation coil 8 and welding torch nozzle 2 through adjustable fixed arm 15:

The electromagnetic heat treatment exciting coil 9 is rigidly connected with the exciting coil 8 welding torch 3 through an adjustable fixed arm 15. The adjustable fixed arm 15 can change the distance between the welding torch 3 and the exciting coil 9 to achieve reasonable welding speed under different welding speeds. Electromagnetic composite field surfacing application method.

3. Auxiliary electric field application equipment:

A pair of movable auxiliary electric field electrodes 13 and 14 are adopted, one of which is connected to the negative pole and the other is connected to the positive pole, and the welding power supply 5 provides current. The moving auxiliary electric field electrode 13 and auxiliary electric field electrode 14 have good contact performance with the workpiece, have certain high temperature wear resistance and good conductivity, and are simple in structure and easy to replace.

The auxiliary electric field electrode 13 can be replaced by tungsten argon arc welding torch (TIG), or plasma welding torch (PAW), or laser welding torch (EBW), or electron beam welding torch (EBW), etc. Electrodes, forming a composite welding torch surfacing welding method. For example, the auxiliary electric field electrode 13 is replaced by a TIG surfacing welding torch, forming a composite welding torch surfacing welding method in the form of TIG+MAG/MIG or TIG+CO ₂ two welding torches with a single surfacing welding pool; for example, the auxiliary electric field electrode 13 It is replaced by the melting pole welding torch (MAG/MIG/CO2) to form a double-wire composite surfacing method.

4. Excitation power supply 10 and welding power supply 5:

A power supply capable of generating time-varying or constant excitation currents of various frequencies and intensities may be used.

A digital inverter welding power source capable of generating various waveforms can be used, and an appropriate auxiliary electric field current can be provided.

3. The above-mentioned electromagnetic composite field controlled molten electrode surfacing method and the expanded application of general equipment

1. Expanded application in the following MIG shielded welding:

(1) For high-efficiency melting electrode welding, or ordinary melting electrode welding.

(2) For welding in the following materials: low carbon steel, alloy steel, special steel, stainless steel, copper and its alloys, aluminum and its alloys, magnesium and its alloys, titanium and its alloys and other ferrous and non-ferrous metals and its alloy.

(3) Various types of welding joints, such as butt joints, lap joints, fillet joints, and all-position welding, are used for non-groove or beveled joints.

(4) It is used in the field of single gas shielded melting electrode welding, or binary or multi-component mixed gas shielded melting electrode welding.

2. Application in other welding processes:

When the electromagnetic stirring excitation coil 8 is not directly integrated with the welding torch nozzle 2, or the water cooling system in the welding torch nozzle 2 is not adopted, the welding wire 6 and shielding gas are used or not, and the welding torch 3 is replaced (such as using a plasma arc Under the conditions of welding torch, submerged arc welding torch and other welding process methods such as specific welding torch), the excitation power supply 10, the excitation equipment and the water cooling system located in the excitation coil support 1 are used in the following welding process, for the workpiece 7 Realize other electromagnetic composite field welding process:

Implemented by electromagnetic composite field: melting inert gas welding (MIG), or melting active gas welding (MAG), or tungsten inert gas welding (TIG), or submerged arc welding (SAW), or carbon dioxide welding ( CO ₂ ), or electroslag welding (ESW), or plasma arc welding (PAW), or electron beam welding (EBW), or resistance welding (RW), or friction welding (FW), or friction stir welding (FSW), or laser welding (LBW).

3. Application in other surfacing welding:

(1) For high cladding rate (high speed) gas shielded surfacing welding, or ordinary gas shielded welding surfacing, or non-gas shielded welding, or plasma surfacing, or laser surfacing, or friction stir Overlay welding, or electrode arc overlay welding;

(2) For surfacing welding of the following materials (or alloy powder): medium-high carbon wear-resistant alloy (cast iron), high-temperature hard alloy, stainless steel and its alloy and other metals and their alloys (or alloy powder);

(3) For single-layer surfacing welding, multi-layer surfacing welding of a single material, or single-layer surfacing welding, multi-layer surfacing welding of multiple materials, or multi-layer surfacing welding of gradient materials;

Among them, the process parameters for the electromagnetic composite field control molten electrode surfacing method are as follows:

(1) The process parameters of electromagnetic compound field controlled melting electrode gas shielded surfacing welding are: welding current 60~800A; electromagnetic stirring magnetic field strength 0.01~10T, electromagnetic stirring magnetic field frequency 1~20Hz; auxiliary electric field current 0~50A, auxiliary electric field current ( When used as a composite welding torch) 0~300A; electromagnetic heat treatment magnetic field strength 0.01~20T, electromagnetic heat treatment magnetic field frequency 1~100Hz, surfacing welding speed 0.01~5m/min, gas flow 1~40L/min;

(2) Electromagnetic composite field controlled non-melting pole gas shielded surfacing welding process parameters are: welding current 60 ~ 300A, electromagnetic stirring magnetic field strength 0.01 ~ 6T, electromagnetic stirring magnetic field frequency 1 ~ 20Hz, auxiliary electric field current 0 ~ 50A, auxiliary electric field current (When used as a composite welding torch) 0~250A, electromagnetic heat treatment magnetic field strength 0.01~10T, electromagnetic heat treatment magnetic field frequency 1~100Hz, surfacing welding speed 0.01~2m/min, gas flow 2~30L/min;

(3) Electromagnetic composite field controlled laser surfacing welding process parameters are: laser surfacing welding power 0.1KW ~ 10KWA, electromagnetic stirring magnetic field strength 0.01 ~ 8T, electromagnetic stirring magnetic field frequency 1 ~ 20Hz, auxiliary electric field current 0 ~ 50A, auxiliary electric field current ( When used as a composite welding torch) 0~300A, electromagnetic heat treatment magnetic field strength 0.01~10T, electromagnetic heat treatment magnetic field frequency 0~50Hz, surfacing welding speed 0.1~5m/min;

(4) Electromagnetic composite field control resistance welding process parameters are: electromagnetic stirring magnetic field strength 0.02 ~ 10T, electromagnetic stirring magnetic field frequency 1 ~ 20Hz, and other common resistance welding parameters;

(5) Electromagnetic composite field control friction stir surfacing process parameters are: electromagnetic stirring magnetic field strength 0.01 ~ 10T, electromagnetic stirring magnetic field frequency 1 ~ 20Hz, auxiliary electric field current 0 ~ 200A, electromagnetic heat treatment magnetic field strength 0.01 ~ 20T, electromagnetic heat treatment magnetic field frequency 1～100Hz, others are friction stir surfacing parameters;

(6) Electromagnetic composite field controlled submerged arc surfacing welding process parameters are: welding current 200~800A, electromagnetic stirring magnetic field strength 0.01~8T, electromagnetic stirring magnetic field frequency 1~30Hz, auxiliary electric field current 0~80A, electromagnetic heat treatment magnetic field strength 0.01~ 20T, electromagnetic heat treatment magnetic field frequency 1-100Hz, welding speed 0.1-5m/min, no shielding gas.

The working process of this equipment is briefly described below:

As shown in Figure 1, the electromagnetic stirring excitation coil 8 of the present invention and the electromagnetic heat treatment excitation coil 9 provide excitation current through the same or different excitation power supply 10, and produce time-varying or constant, dual-frequency or single-frequency external longitudinal magnetic fields; the present invention The auxiliary electrode provides welding current and auxiliary current through the same or different power supply 5 to generate welding current with various waveforms and appropriate auxiliary electric field current. Among them: the longitudinal magnetic field generated by the electromagnetic stirring excitation coil 8 is mainly used to control the periodic rotational movement of the welding arc, the melting of the welding wire, the formation and detachment of the molten droplet at the end of the welding wire, and the movement state of the liquid stream to form a periodic and stable molten droplet. The transition state of the rotating jet; at the same time, it also controls the flow mode of the melt in the molten pool and the stirring intensity of the molten pool, and changes the solidification state of the metal in the molten pool. The longitudinal magnetic field generated by the electromagnetic heat treatment excitation coil 9 can effectively control the transformation process of the solidified structure of the weld, play a role in heat treatment, promote grain refinement, reduce chemical inhomogeneity, improve the plasticity and toughness of the weld, and improve the structure of the weld The grain size, distribution and structural state of the crystal, using the systematic control of comprehensive parameters to achieve a high-quality surfacing functional layer.

During actual surfacing welding, according to different surfacing welding processes, surfacing welding base metal materials, surfacing welding materials and surfacing welding forms, etc., the surfacing welding control method and surfacing welding equipment provided by the present invention are adopted, and the electromagnetic composite field and surfacing welding process are comprehensively considered. Reasonable matching of parameters and systematic optimization of these main process parameters can ensure the implementation of high-efficiency, high-quality, and low-cost surfacing processes.

Four. Concrete embodiment:

The following embodiments are implemented according to the surfacing welding method and equipment provided by the present invention.

Example 1: When applying intermittent alternating longitudinal magnetic field to control carbon dioxide surfacing welding flux-cored wire Fe-Cr-Mn-W-V series high-carbon high-chromium alloy, the surfacing process parameters are as follows to obtain a good surfacing welding function layer: the excitation current of the electromagnetic stirring magnetic field is 3~20A, electromagnetic stirring magnetic field frequency 1~6Hz, welding current 100~200A, welding speed 0.3~0.8m/min, 100% carbon dioxide shielding gas 5~20L/min, wire feeding speed 3.5~0.8m/min.

Example 2: When an external electromagnetic composite field is applied to control MAG surfacing welding of Cr-W-Co hard alloys, the surfacing process parameters are as follows to obtain a good surfacing welding functional layer: the welding current is 120-180A, and the electromagnetic stirring magnetic field frequency is 1- 4Hz, auxiliary electric field strength current 10A ~ 40A, welding speed 0.3 ~ 1m/min. The intensity of the electromagnetic heat treatment magnetic field is 0.01T-0.2T, the frequency of the electromagnetic heat treatment magnetic field is 1-20Hz, and the flow rate of the protective gas (100% pure argon) is 5-20L/min.

Example 3: When the high-efficiency MAG surfacing welding of Fe-Ni-Cr-B-Si alloy is controlled by an external electromagnetic compound field, the surfacing welding process parameters are as follows to obtain a good surfacing welding functional layer: welding current is 350-700A, electromagnetic stirring magnetic field excitation current 5-30A, electromagnetic stirring magnetic field frequency 1-8Hz, auxiliary electric field strength current 5A-30A, welding speed 0.8-4m/min. The excitation current of the magnetic field for electromagnetic heat treatment is 15-40A, the frequency of the magnetic field for electromagnetic heat treatment is 1-25Hz, and the flow rate of protective gas (100% pure argon) is 20-30L/min.

Example 4. When applying intermittent alternating longitudinal magnetic field to control submerged arc automatic surfacing welding of Fe-Cr-Si-B alloys, the surfacing welding process parameters are as follows to obtain a good surfacing welding functional layer: welding current is 280-450A, electromagnetic stirring magnetic field excitation The current is 2-35A, the electromagnetic stirring magnetic field frequency is 1-12Hz, and the welding speed is 0.1-3.6m/min.

Example 5. When the external electromagnetic composite field is used to control MAG surfacing welding, powder-cored welding wire a is used. The surfacing welding process parameters are as follows to obtain a good surfacing welding functional layer: welding current is 100-250A, electromagnetic stirring magnetic field excitation current is 5-30A, electromagnetic Stirring magnetic field frequency is 1-8Hz, auxiliary electric field strength current is 3A-20A, welding speed is 0.1-2m/min, electromagnetic heat treatment magnetic field excitation current is 10-35A, electromagnetic heat treatment magnetic field frequency is 1-32Hz, 10-30% nitrogen + residual Percentage of argon shielding gas, the flow rate is 8-20L/min.

Example 6. When the high-speed surfacing welding of carbon dioxide mixed gas is controlled by an external electromagnetic compound field, powder cored wire b is used. The surfacing welding process parameters are as follows to obtain a good surfacing welding function layer: welding current is 200-450A, and the excitation current of electromagnetic stirring magnetic field is 3- 28A, the electromagnetic stirring magnetic field frequency is 1-10Hz, the auxiliary electric field strength current is 2A-34A, the welding speed is 0.4-2.5m/min, the electromagnetic heat treatment magnetic field excitation current is 16-42A, the electromagnetic heat treatment magnetic field frequency is 1-32Hz, 10-20 The % protective gas is carbon dioxide + the remaining percentage of argon, and the flow rate is 5-30L/min.

Example 7. When the external electromagnetic composite field is used to control MAG surfacing welding, powder cored wire c is used, and the surfacing welding process parameters are as follows to obtain a good surfacing welding functional layer: welding current is 120-280A, electromagnetic stirring magnetic field excitation current is 2-24A, electromagnetic The stirring magnetic field frequency is 1-10Hz, the auxiliary electric field strength current is 6A-30A, and the welding speed is 0.1-2.4m/min. The excitation current of the magnetic field for electromagnetic heat treatment is 10-38A, the frequency of the magnetic field for electromagnetic heat treatment is 1-28Hz, the protective gas is 100% argon, and the flow rate is 4-30L/min.

It can be seen from the above examples that the reasonable matching of the electromagnetic composite field and the surfacing welding process parameters should be considered comprehensively, such as the length of the welding wire, the composition of the shielding gas, the welding arc voltage, the strength and mode of the auxiliary electric field, the strength and frequency of the electromagnetic stirring field, the strength and frequency of the electromagnetic heat treatment field and Frequency, etc., and systematically optimize these main process parameters according to the actual surfacing objects and materials, so as to ensure high-quality surfacing functional layers.

The present inventor finds in the basic theory and engineering application research of electromagnetic composite field welding technology, electromagnetic composite field surfacing welding technology has the following main beneficial effects: (1) change arc force and current density distribution, reduce electric arc to parent metal The concentrated heating degree and excavation effect are beneficial to reduce the dilution rate; (2) It can realize the stable jet transition of powder cored wire droplet, which is beneficial to improve the cladding rate; (3) Effectively stir the molten pool to change the solidification process and temperature distribution (The structure and phase structure will also change), refine the grain, uniform composition, reduce the defects of the surfacing layer, help to improve the ductility and plasticity, and form a high-quality weld; (4) reduce the residual stress level of the surfacing layer and promote the surfacing The reasonable thermal stress distribution of the layer affects the secondary crystallization structure and structure of the surfacing layer, which is conducive to promoting the dispersion distribution of carbide hard phase, the formation of toughened structure and the formation of spheroidized structure of precipitated phase, and reduces the defects of surfacing layer ( Such as pores, inclusions, etc.), improve toughness and plasticity, and form a high-quality surfacing layer. (5) Reduce the spatter of high-efficiency gas shielded surfacing welding, improve the quality of surfacing welding, and help realize high-efficiency and high-quality surfacing welding process at low cost, cancel or reduce the technical requirements for surfacing welding process (including welding materials and pre-welding preheating Requirements) and harsh conditions of heat treatment. (6) The transfer behavior of the welding droplet is the final result of the comprehensive action of various forces on the droplet, while the high-efficiency gas shielded welding arc is a typical plasma (including charged particles and neutral particles), and the rotating jet transfers the droplet It is a kind of fine metal droplets moving at high temperature and high speed. Its behavior must be affected by particle motion and external electromagnetic field. It controls the movement of particles and fine droplets in the arc, and directly or indirectly controls the transition behavior of molten droplets. , so it can replace helium to realize a stable rotating jet droplet transfer process. (7) It is more conducive to the surfacing of gradient materials. The basic principle of the present invention is that under the action of the electromagnetic composite field, the surfacing process and the surfacing layer are induced comprehensively, resulting in favorable transformation and influence, so that the high hardness, ductility and plasticity of the surfacing welding, and the high cladding rate take low dilution Efficient and reasonable coordination to achieve organic unity.

The inventor found in the research: adopting powder-cored welding wire has the following effects: (1) can adjust material alloy composition and ratio very conveniently and flexibly, obtain the surfacing layer or gradient surfacing layer of different kinds of alloy materials, be beneficial to realize Mechanization and automation, no complex metallurgical preparation process and smelting equipment, breaking through time and space and many other constraints; (2) It is conducive to improving the efficiency and quality of surfacing welding, reducing defects and reducing surfacing welding costs; (3) It can avoid plasma and laser powder accumulation Cladding is limited by time and space (including submerged arc surfacing); (4) It can avoid the defects caused by uneven powder feeding in powder cladding (surfacing welding), and the high cost of laser cladding; (5) Overlay welding materials (electrode, welding wire, flux, etc.) at home and abroad are very rich in variety, welding wire manufacturing equipment and technology are relatively mature, and there are many research results that can be used for reference, which is conducive to the selection and rapid development of material surfacing welding powder cored wire components.

Claims (8)

1. An electromagnetic composite field melting electrode overlay welding method is characterized in that: it is an electromagnetic composite field control powder cored wire molten droplet jet transition melting electrode gas shielded overlay welding method, and the specific method is: on the top of the overlay welding workpiece (7) , using a pair of electromagnetic stirring excitation coils (8) and electromagnetic heat treatment excitation coils (9), the electromagnetic stirring excitation coils (8) are coaxial with the welding torch (3); the excitation current is provided by the excitation power supply (10) to generate electromagnetic stirring and Electromagnetic heat treatment and external longitudinal magnetic field; apply movable first auxiliary electric field electrode (13) and second auxiliary electric field electrode (14) on the surfacing welding seam to generate auxiliary electric field; welding power source (5) provides surfacing welding and auxiliary electric field current , the first auxiliary electric field electrode (13) is of the same polarity as the torch contact tip (3); the electromagnetic compound field realizes electromagnetic compound field control of high cladding melting electrode gas shielded surfacing welding on the welding workpiece (7). 2. The method of electromagnetic composite field control melting pole surfacing welding according to claim 1 is characterized in that: electromagnetic stirring excitation coil (8) and electromagnetic heat treatment excitation coil (9) are connected with different frequency, unequal intensity and time-varying Excitation current, using a magnetic field with a higher frequency and a weaker intensity for electromagnetic stirring, to control the welding arc, droplet shedding at the end of the welding wire and the stability of the liquid stream during the transition of the rotating jet, and has the effect of auxiliary induction heating It promotes the melting of the welding wire and the formation of droplets, and can fully stir the melt of the welding pool; and the use of a magnetic field with a lower frequency and a larger intensity for electromagnetic heat treatment can change the crystallization status of the molten pool metal, change the solidification process and The temperature distribution, microstructure, and phase structure will also change, which will promote the refinement of weld grains, reduce chemical inhomogeneity, and reduce the sensitivity of pores, which will help improve toughness and plasticity and form a high-quality surfacing layer; for surfacing workpieces (7 ) to realize the electromagnetic composite field surfacing process that meets the surfacing requirements; Alternatively, the electromagnetic stirring excitation coil (8) and the electromagnetic heat treatment excitation coil (9) are connected to the excitation power supply (10) at the same time to generate a time-varying longitudinal electromagnetic field of the same frequency, same phase and same strength or a constant longitudinal electromagnetic field of uniform strength. 7) Realize the electromagnetic composite field surfacing welding process that meets the surfacing welding process requirements; Alternatively, the electromagnetic stirring excitation coil (8) and the electromagnetic heat treatment excitation coil (9) are used separately, and an excitation power supply (10) is applied to generate a time-varying longitudinal electromagnetic field or a constant longitudinal electromagnetic field of uniform intensity, and separate electromagnetic stirring or Electromagnetic heat treatment; Including the following process conditions: surfacing welding current 80-800A, wire feeding speed 0-50m/min, wire diameter 0.8-6mm, shielding gas flow 1-50L/min, welding voltage 1-60V, welding speed 0.01-6m /min, excitation current 0～60A, excitation frequency 0～100Hz, auxiliary field current 0～300A; Including three kinds of powder-cored welding wire: welding wire a, or welding wire b, or welding wire c; the specific formula of powder-cored welding wire is as follows: The welding wire a is composed of C, Cr, Ni, Mo, Mn, Si, N, and rare earth alloy powders. %, Mo 0.78～0.91%, Mn 0.65～1.61, Si 0.16～0.96%, N0.02～0.04%, rare earth 0.01～3.2%; S≤0.01%, P≤0.025%; the mixture of argon and nitrogen is used Protective gas, its volume percentage is: 10-30% nitrogen + the rest is argon; The welding wire b is composed of C, Cr, Ni, Si, B, Mn alloy powders, and the metal powder core is composed of W t%: C0.08～0.17%, Cr 10.2～18.3%, Ni 3.4～5.8%, Si 0.38 ～0.81%, B 0.14～0.34%, Mn 0.68～1.61%; the protective gas is composed of carbon dioxide and argon mixed, and its volume percentage is: 10～20% carbon dioxide + the rest is argon; The welding wire c is composed of C, Cr, W, Mo, V, Nb, and rare earth alloy powders. 0.38～3.41%, V 0.24～0.38%, Nb 2.3～5.8%, rare earth 0.01～4.6%; the protective gas is 100% argon. 3. An electromagnetic compound field melting pole surfacing equipment is characterized in that an excitation power supply, an excitation device, an auxiliary electric field device and a water cooling system are provided; the excitation device is an electromagnetic stirring excitation coil (8) and an electromagnetic heat treatment excitation coil (9), The electromagnetic stirring excitation coil (8) and the electromagnetic heat treatment excitation coil (9) provide excitation current through the excitation power supply (10); Power supply; electromagnetic stirring excitation coil (8) and electromagnetic heat treatment excitation coil (9) are axisymmetric cylindrical structures, which are respectively arranged on the first bracket (1) and the second bracket (12); the electromagnetic stirring excitation coil (8) is fixed On the welding torch (3), and coaxial with the welding torch (3); at the end of the first bracket (1) of the electromagnetic stirring excitation coil (8), a clamping lock connected to the welding torch (3) is provided mechanism, which fixes the electromagnetic stirring excitation coil (8) on the welding torch nozzle (2), so that the electromagnetic stirring excitation coil (8) has a certain distance from the workpiece (7); the welding torch (3) and the electromagnetic heat treatment The distance between the exciting coils (9) can be adjusted, and a water cooling system is installed in the first support (1) and the second support (12); The auxiliary electric field equipment is mainly composed of a movable first auxiliary electric field electrode (13) and a second auxiliary electric field electrode (14), one of which is connected to the negative pole and the other is connected to the positive pole, and the current is provided by the welding power source (5); the first auxiliary electric field electrode The electric field electrode (13) has the same polarity as the welding torch contact tip (3); the first auxiliary electric field electrode (13) can be tungsten argon arc welding torch TIG, or plasma welding torch PAW, or laser welding torch EBW, or electron Beam welding torch EBW is replaced to form melting electrode and non-melting electrode composite welding torch surfacing mode; the first auxiliary electric field electrode (13) is replaced by melting electrode torch MAG/MIG/CO2 to form a double wire composite surfacing welding method. 4. The electromagnetic compound field control melter overlay welding equipment according to claim 3, characterized in that: the electromagnetic stirring excitation coil (8) and the electromagnetic heat treatment excitation coil (9) are respectively provided with a first permeable core ( 4) and the second magnetically conductive core (11); the first magnetically conductive core (4) and the second magnetically conductive core (11) are movably installed in the electromagnetic stirring excitation coil (8) and the electromagnetic heat treatment excitation coil (9), It can freely adjust its position in the electromagnetic stirring excitation coil (8) and the electromagnetic heat treatment excitation coil (9) until all are removed from the electromagnetic stirring excitation coil (8) and the electromagnetic heat treatment excitation coil (9); the first permeable core ( 4) and the shape of the end of the second magnetically permeable core (11) is funnel-shaped, straight barrel-shaped or conical. 5. The electromagnetic compound field controlled melting pole surfacing equipment according to claim 3, characterized in that: the electromagnetic heat treatment excitation coil (9) is connected to the electromagnetic stirring excitation coil (8) by an adjustable fixed arm (15) It is rigidly connected with the welding torch (3), and the adjustable fixed arm (15) can change the distance between the welding torch (3) and the electromagnetic heat treatment excitation coil (9), so as to realize reasonable application of electromagnetic composite field surfacing at different welding speeds Way; Or, the electromagnetic stirring excitation coil (8) is directly integrated with the welding torch nozzle (2), an insulating material is used to keep the outer wall of the welding torch nozzle (2) and the turns of the electromagnetic stirring excitation coil (8) in an insulated state, and It is cooled by the water cooling system built inside the torch nozzle (2). 6. The electromagnetic composite field melting pole surfacing equipment according to claim 3, characterized in that: the first support (1) of the electromagnetic stirring excitation coil (8) and the second support (12) of the electromagnetic heat treatment excitation coil (9) The water cooling system in ) adopts a cover-type rectangular pulse-shaped condensate flow pattern, and the first bracket (1) and the second bracket (12) are respectively provided with water flow grooves (16) and two drainage partitions (18) arranged in a staggered manner , the two drain flow partitions (18) are connected to the outer baffles (17) on both sides of the water flow groove (16) respectively; The water cooling system in the welding torch nozzle (2) adopts a cover-type spiral condensed water flow pattern, and its structure is: a spiral threaded water flow groove (20) is designed in the welding torch nozzle wall (21), combined with the welding torch nozzle The baffle (19) forms an omnidirectional condensed water channel in the torch nozzle, so that the condensed water flows in a spiral shape around the torch nozzle and reaches the end of the torch nozzle. 7. A method for surfacing welding with electromagnetic composite field control according to claim 1 or 2 and the application of the composite electromagnetic field control melting electrode surfacing equipment described in claim 3, 4, 5 or 6 in the following aspects: For high cladding rate MIGMA welding, or ordinary MIGA welding, or non-MIGAS welding, or plasma surfacing, or laser surfacing, or friction stir surfacing, or electrode arc Surfacing; For surfacing welding of the following materials: cast iron, medium and high carbon wear-resistant alloys, nickel-based alloys, iron-based alloys, cobalt-based alloys, hard alloys, stainless steel and their alloys; For single-layer surfacing welding, multi-layer surfacing welding of a single material, or single-layer surfacing welding, multi-layer surfacing welding of multiple materials, or multi-layer surfacing welding of gradient materials; It is used for the manufacture and repair of molds, the repair of mechanical equipment, the repair of metallurgical equipment and mining equipment. 8. purposes according to claim 7, it is characterized in that: adopt following welding process, realize other electromagnetic composite field welding processes to workpiece (7): For high-efficiency melting electrode welding, or ordinary melting electrode welding; For welding solid wire, flux cored wire and powder cored wire; For welding in the following materials: low carbon steel, alloy steel, special steel, stainless steel, copper and its alloys, aluminum and its alloys, magnesium and its alloys, and titanium and its alloys; It is used for butt joint, lap joint, fillet joint and all-position welding for various welding joint forms; It is used in the field of single gas shielded melting electrode welding, or binary or multi-component mixed gas shielded melting electrode welding; Implementation using electromagnetic composite field: metal inert gas shielded welding MIG, or molten pole active gas shielded welding MAG, or tungsten inert gas shielded welding TIG, or submerged arc welding SAW, or carbon dioxide welding CO ₂ , or electroslag welding ESW, Or plasma arc welding PAW, or electron beam welding EBW, or resistance welding RW, or friction welding FW, or friction stir welding FSW, or laser welding LBW; in: (1) Electromagnetic composite field control melting electrode gas shielded surfacing welding process parameters are: welding current 60 ~ 800A; electromagnetic stirring magnetic field strength 0.01 ~ 10T, electromagnetic stirring magnetic field frequency 1 ~ 20Hz; auxiliary electric field current 0 ~ 50A, used as a composite welding torch When used, the auxiliary electric field current is 0-300A; the electromagnetic heat treatment magnetic field strength is 0.01-20T, the electromagnetic heat treatment magnetic field frequency is 1-100Hz, the surfacing welding speed is 0.01-5m/min, and the gas flow rate is 1-40L/min; (2) Electromagnetic compound field control non-melting electrode gas shielded surfacing welding process parameters are: welding current 60 ~ 300A, electromagnetic stirring magnetic field strength 0.01 ~ 6T, electromagnetic stirring magnetic field frequency 1 ~ 20Hz, auxiliary electric field current 0 ~ 50A, for composite welding When the torch is used, the auxiliary electric field current is 0-250A, the magnetic field strength of electromagnetic heat treatment is 0.01-10T, the magnetic field frequency of electromagnetic heat treatment is 1-100Hz, the surfacing welding speed is 0.01-2m/min, and the gas flow rate is 2-30L/min; (3) Electromagnetic compound field controlled laser surfacing welding process parameters are: laser surfacing welding power 0.1KW ~ 10KWA, electromagnetic stirring magnetic field strength 0.01 ~ 8T, electromagnetic stirring magnetic field frequency 1 ~ 20Hz, auxiliary electric field current 0 ~ 50A, used as a composite welding torch The auxiliary electric field current is 0-300A, the magnetic field strength of electromagnetic heat treatment is 0.01-10T, the magnetic field frequency of electromagnetic heat treatment is 0-50Hz, and the surfacing welding speed is 0.1-5m/min; (4) Electromagnetic compound field control resistance welding process parameters are: electromagnetic stirring magnetic field strength 0.02 ~ 10T, electromagnetic stirring magnetic field frequency 1 ~ 20Hz; (5) Electromagnetic composite field control friction stir surfacing process parameters are: electromagnetic stirring magnetic field strength 0.01 ~ 10T, electromagnetic stirring magnetic field frequency 1 ~ 20Hz, auxiliary electric field current 0 ~ 200A, electromagnetic heat treatment magnetic field strength 0.01 ~ 20T, electromagnetic heat treatment magnetic field frequency 1～100Hz; (6) Electromagnetic composite field controlled submerged arc surfacing welding process parameters are: welding current 200~800A, electromagnetic stirring magnetic field strength 0.01~8T, electromagnetic stirring magnetic field frequency 1~30Hz, auxiliary electric field current 0~80A, electromagnetic heat treatment magnetic field strength 0.01~ 20T, electromagnetic heat treatment magnetic field frequency 1-100Hz, welding speed 0.1-5m/min, no shielding gas.

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