CN108723087A - A kind of multi-layer metal composite plate pulse current auxiliary milling method and device - Google Patents

Abstract

A kind of multi-layer metal composite plate pulse current auxiliary milling method and device, it is related to multi-layer metal composite plate material preparation field, is to solve the problems, such as that existing rolling mill practice is prepared the step of multiple layer metal plank combination effect is poor, and pulse current assists milling method：Step 1：Plank pre-treatment；Step 2：Blank is fixed；Step 3：Electric current auxiliary rolling.Multi-layer metal composite plate pulse current auxiliary rolling device includes roller assembly, electrode contact device, conducting wire and the pulse power, the roller assembly is three-layer composite structure, including interior roller, insulation sleeve and conductive sleeve, insulation sleeve is nested together with interior roller, annular conductive sleeve is installed outside insulation sleeve, electrode contact device is installed on conductive sleeve.The present invention is prepared for multi-layer metal composite plate.

Description

A pulse current assisted rolling method and device for a multi-layer metal composite plate

technical field

The invention relates to the field of multilayer metal composite plate preparation, in particular to a pulse current assisted rolling device and method for a multilayer metal composite plate, in particular to a combination of electroplasticity and pulse current local heating effect to combine multilayer metal plate rolling And make it a system with good composite effect.

Background technique

Multi-layer metal composite materials refer to the matching of two or more metal materials with different properties by a certain composite processing technology with a certain thickness of the component layer and the interface, forming a firm metallurgical bond at the interface. Structural materials. Compared with the diffuse distribution among the components of the traditional metal composite material, the components of the multilayer metal composite material are continuously distributed in layers, with alternately distributed component components and interlayer interfaces. The existence of the interface plays an important role in the regulation of the load during the deformation process of the layered material. It can realize the regulation and redistribution of the stress among the components of each layer, so that the multilayer metal composite can withstand greater plastic deformation. Therefore, while maintaining the properties of each component, the multilayer metal composite material can also integrate the advantages of each component, making the multilayer metal composite material have superior performance than a single metal material, and can adapt to harsh working environments. , to meet the harsh material service conditions. At present, the main processes for the preparation of multi-layer metal composite plates are diffusion welding method and rolling composite method.

Diffusion welding is a commonly used processing technology for preparing multilayer metal materials. It can perform diffusion welding on the same or dissimilar materials, and its component layer materials are compounded by interfacial diffusion under the action of heating and pressure. Generally speaking, the diffusion welding interface has good quality and stable performance. However, the diffusion welding process takes a long time, the size of the plate is limited by the diffusion furnace, the production efficiency is low, and it generally needs to be carried out in a vacuum or a protective atmosphere. Usually, a cycle takes at least several hours, the power consumption is large, and the cost of diffusion welding is high. become an important factor restricting its development.

The rolling compound method refers to the strong pressure of the rolling mill to make two or more metals with clean surfaces in contact with each other undergo plastic deformation, break the surface metal layers, form a mechanical bite with each other, and make the layer interfaces between the components tightly bonded. a processing technique. Rolling cladding is an effective process for producing clad sheets. It can continuously produce laminated composite materials in rolls. It has high production efficiency and is easy to realize large-scale industrial production. It is a kind of metal clad cladding with great development potential. Material preparation technology, but the current rolling and compounding process requires a high amount of downforce to promote the plate compounding, which inevitably causes cracks on the edge of the material. In addition, in order to ensure the interfacial bonding strength of the plate during the rolling process, it is necessary to Heating the plates causes the material to form an oxide layer, which reduces the bonding effect of the composite plates.

In recent years, a new type of pulse current assisted rolling technology has been developed. By applying pulse current during the metal rolling process, the local heating effect of the pulse current in the contact area between the material and the roll is combined with the electroplastic effect. The deformation resistance of the material is reduced and the plasticity is increased to achieve a large plastic deformation. The currently designed pulse current rolling system is mostly used in the rolling process of difficult-to-deform single-layer metals, and the current transmission line in the rolling system is complicated and the resistance is large. A method for realizing high-strength and high-plasticity zirconium and zirconium-2 alloys", which only involves the rolling process of single-layer zirconium and zirconium-2 alloys; another example is the authorized announcement number: CN202169276U, and the name is: "An Electromagnetic A system that combines plasticity and warm plasticity to roll metal materials", the electrode devices that are in contact with the rolled piece are respectively installed on the front and rear sides of the roll, and the current is transmitted to the rolling deformation zone through the rolled piece.

The pulse current assisted rolling method mentioned in the above patents is to perform pulse current assisted rolling on a single-layer difficult-to-deform plate, and the current transmission line in the rolling system is complicated, the resistance is large, and the electroplasticity and pulse current local heating cannot be realized. The ideal function of effect rolling combination cannot achieve the purpose of pulse current assisted rolling of multi-layer metal sheets and make it achieve a good composite effect.

Contents of the invention

The present invention aims to solve the problem of poor bonding effect of multi-layer metal plates prepared by the existing rolling process, and proposes a high-efficiency, low-cost pulse-current assisted rolling method for multi-layer metal composite plates that can improve the bonding strength of multi-layer metal composite plates And the device solves the problems of low bonding force and easy cracking in the rolling production process of multi-layer metal clad plates.

The technical scheme that the present invention takes is:

A pulse current assisted rolling method for a multi-layer metal composite plate, said method is realized according to the following steps:

Step 1: Pre-treatment of the plate: punch holes in the four corners of the plate to be rolled; polish the surface to be compounded, remove the oxide layer and other impurities on the surface of the plate, and remove the surface oil;

Step 2: Blank fixing: superimpose the clean surfaces of the surface-treated metal plates, use thin iron wires to penetrate into the reserved holes, and tie the materials tightly to form a composite blank;

Step 3: Current assisted rolling: adjust the parameters of the pulse power supply, turn on the pulse power supply, put the fixed slab between the pulse current assisted rolling devices, so that the current flows from the upper roll assembly through the slab to the lower roll assembly. Connect the loop to complete the current assisted rolling.

The present invention also provides a pulse current assisted rolling device for a multi-layer metal composite plate, which includes a roll assembly, an electrode contact device, a wire and a pulse power supply. The roll assembly is a three-layer composite structure, including an inner roll, an insulating sleeve and a conductive The insulating sleeve and the inner roller are nested together, and the insulating sleeve is equipped with a ring-shaped conductive sleeve, and an electrode contact device is installed on the conductive sleeve. The electrode contact device of the upper roll, the conductive sleeve of the upper roll, the rolling blank, the conductive sleeve of the lower roll, the electrode contact device of the lower roll, the loop wire and the negative pole of the pulse power supply form a current loop.

Compared with the prior art, the beneficial effect of the present invention is that the pulse current assisted rolling device and method of the multi-layer metal composite plate of the present invention have the advantage of applying high-energy pulse current synchronously during the rolling process of the composite plate to be processed, so that the material The rolling cladding is completed under the interaction of plasticity and local heating effect of pulse current. According to the theory of electroplasticity, under the influence of high-energy pulse current, when the current passes through the interior of the material, because the electron speed is much faster than the dislocation speed, a large number of electrons will drag the dislocation movement in the lattice, or transfer energy to the dislocation. Wrong, it will also accelerate the diffusion of internal atoms, reduce the flow stress of the material, increase the plasticity, and improve the formability of the material. In addition, when the current passes through the metal, Joule heat will be generated, so that the material is in a thermally activated deformation state, which increases the rolling bonding force of the composite plate interface; reduces the resistance of the material when it deforms, and increases the plasticity of the material. When the plate is rolled and compounded, it can withstand Greater downforce without cracking.

Compared with the prior art, the pulse current assisted rolling device and method of the multi-layer metal composite plate of the present invention have the following outstanding advantages compared with the traditional metal plate rolling composite method and other pulse current assisted rolling methods:

1. Compared with the traditional metal plate rolling composite method, the multilayer metal composite plate pulse current assisted rolling device adopted in the present invention applies pulse current to the multilayer metal plate in the rolling process to improve the atomic diffusion ability. Under the action of pulse current Joule heat, the local heating effect of pulse current is realized to complete the rolling process, which avoids the heating process of traditional composite sheet rolling composite process, saves energy, and avoids heating oxidation and roll sticking on the surface of hot-rolled metal composite sheet materials Phenomenon. In a word, the present invention can integrate the interaction of electroplasticity and electrothermal effect, greatly reduce the deformation resistance of the material during the rolling process, reduce the residual stress of the material, and prevent the material from rebounding and cracking after rolling and subsequent use. Phenomenon, increase the bonding force between layered metal sheets, so that composite sheets can be more firmly combined.

2. Compared with the existing electroplastic rolling metal material method and system, the advantage of the pulse current assisted rolling device and method of the multilayer metal composite plate used in the present invention is that the pulse current assisted rolling system used in the present invention The pulse current is directly connected to the conductive sleeve of the upper roll by the positive pole of the pulse power supply through the upper roll electric contact device, flows into the conductive sleeve of the lower roll through the rolling deformation area of the rolled piece, and finally flows back to the negative pole of the pulse power supply by the lower roll electrical contact device. During this process, the current will not flow through the rolling mill body and the non-rolling deformation area of the rolled piece, which avoids the loss of the pulse current in the external circuit; it can realize the local Joule heating effect of the pulse current in the rolling deformation area, avoiding the pulse current in the rolling deformation area. The Joule heating effect in the undeformed area will cause the formation of an oxide layer on the surface of the material, which will affect the bonding performance of the composite plate. The invention can achieve greater current density in the rolling deformation zone of the rolled piece under the same pulse power and rolling conditions, has a simple and practical structure, avoids energy waste, and greatly improves the bonding force of the multilayer metal plate interface.

Description of drawings

Fig. 1 is the schematic diagram of the pulse current assisted rolling principle of the multilayer metal composite sheet material of the present invention;

Fig. 2 is the schematic diagram of pulse current assisted rolling device of multilayer metal clad plate of the present invention;

Fig. 3 is the schematic cross-sectional view of the connection structure of roll, insulating sleeve and conductive sleeve of the present invention;

Figures: 1. Pulse power supply, 2. Lead wire, 3. Roll assembly, 4. Rolling composite billet, 5. Electrode contact device, 6. Conductive sleeve, 7. Insulating sleeve, 8. Inner roll, 13. Rolling mill stand , 14, pressing down the screw, 15, the upper roller bearing, 16, the upper bearing support frame, 17, the lower roller bearing, 18, the lower bearing support frame, 19, the blind hole threaded hole of the insulating sleeve, 20, the fixing bolt of the insulating sleeve conductive sleeve , 21, conductive sleeve countersunk threaded hole, 22, inner roller threaded hole, 23, inner roller insulating sleeve fixing bolt, 24, insulating sleeve countersunk threaded hole.

Detailed ways

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

With reference to Fig. 1, the present invention provides a pulse current assisted rolling method for a multilayer metal composite plate, said method is realized according to the following steps:

Step 1: Pre-treatment of the plate: punch holes in the four corners of the plate to be rolled; polish the surface to be compounded, remove the oxide layer and other impurities on the surface of the plate, and remove the surface oil;

Step 2: Blank fixation: superimpose the clean surfaces of the surface-treated plates, use thin iron wires to penetrate into the reserved holes, and tie the materials tightly to form a rolled composite slab 4;

Step 3: Current-assisted rolling: adjust the parameters of the pulse power supply 1, switch on the pulse power supply 1, put the fixed rolled composite slab 4 between the pulse current-assisted rolling devices, and make the current flow from the upper roller assembly through rolling The composite slab flows into the lower roll assembly to form a connected circuit to complete the current-assisted rolling.

The surface treatment of the plate in the above step 1 is to use a wire brush to polish the surface to be composited; use acetone and absolute ethanol solution to ultrasonically clean the surface to remove surface oil. Ensure that the surface to be compounded is clean and does not affect the rolling of the compounded slab. The surface-treated plate is a metal plate, such as aluminum alloy, magnesium alloy, copper and other metal plates and strips.

Referring to Fig. 1-Fig. 3 explanation, the present invention also provides a kind of pulse current assisted rolling device of multi-layer metal clad plate realizing above-mentioned rolling method, it comprises roll assembly 3, electrode contact device 5, lead wire 2 and pulse power supply 1, The roll assembly is a three-layer composite structure, including an inner roll 8, an insulating sleeve 7 and a conductive sleeve 6, the insulating sleeve 7 and the inner roll 8 are nested together in an interference fit, the insulating sleeve 7 is externally equipped with a ring-shaped conductive sleeve 6, and the conductive sleeve 6 is equipped with an electrode contact device 5, the pulse power supply 1 is connected to the electrode contact device 5 through a wire 2, and the pulse current passes through the positive electrode of the pulse power supply, the wire, the electrode contact device 5 of the upper roll, the conductive sleeve 6 of the upper roll, and the rolled composite plate The blank 4, the conductive sleeve 6 of the lower roll, the electrode contact device 5 of the lower roll, the loop wire and the negative electrode of the pulse power supply form a current loop.

Inner roll 8 is the roll of common rolling mill. A plurality of inner roller threaded holes 22 are processed uniformly along the circumferential direction on the outer peripheral side of the inner roller 8, and the insulating sleeve countersunk threaded holes 24 corresponding to the number of inner roller threaded holes 22 are uniformly processed on the outer peripheral side of the insulating sleeve 7 along the circumferential direction. 8 is connected with the insulating sleeve through the inner roller insulating sleeve fixing bolt 23 installed in the inner roller threaded hole 22 and the insulating sleeve countersunk screw hole 24. The insulating sleeve 7 is uniformly processed with a plurality of insulating sleeve blind hole threaded holes 19 along the circumferential direction, and the conductive sleeve is uniformly processed along the circumferential direction with conductive sleeve countersunk screw holes 21 consistent with the number of insulating blind hole threaded holes. The insulating sleeve 7 is installed on the insulating The insulating sleeve conductive sleeve fixing bolt 20 in the blind hole threaded hole 19 and the conductive sleeve countersunk screw hole 21 is connected with the conductive sleeve 6 .

The number and position distribution of the insulating sleeve countersunk threaded holes 24 of each group of insulating sleeves 7 correspond to the number and position distribution of the inner roller threaded holes 22 on the circumference of the inner roller 8, and then the insulating sleeve 7 is set on the inner roller 8 to make the thread The holes are aligned, and the inner roller insulating sleeve fixing bolt 23 is screwed in the threaded holes of the insulating sleeve 7 and the inner roller 8. It should be noted that the fixing bolts of the inner roller insulating sleeve should be completely sunk into the insulating sleeve 7 to ensure that the fixing bolts of the inner roller insulating sleeve do not contact the outer conductive sleeve 6 and prevent the bolts from forming a current path between the conductive sleeve 6 and the inner roller 8 , to prevent the bolt from passing the current of the outer conductive sleeve 6 into the inner roller 8 and the rolling stand 13 during the pulse current auxiliary rolling process. Three conductive sleeve countersunk threaded holes 21 are evenly distributed on the circumference of the left and right ends of the conductive sleeve 6, and an insulating sleeve blind hole threaded hole 19 is distributed on the position corresponding to the insulating sleeve 7. The conductive sleeve 6 Cooperate with the insulating sleeve 7, align the threaded holes, and screw the bolts to fix the conductive sleeve 6 and the insulating sleeve 7. It should be noted that in order to prevent the insulating sleeve conductive sleeve fixing bolt 20 from penetrating through the insulating sleeve 7 to connect the conductive sleeve 6 and the inner roller 8 to form a power path, the threaded hole of the insulating sleeve 7 is a blind hole, and the selected bolt length is moderate. In the roll assembly 3 thus obtained, after the conductive sleeve 6 is energized, the current will not be transmitted to the rolling mill body through the inner roll 8, so as to avoid safety problems and current consumption caused by electrification of the rolling mill. The cooperation between the conductive sleeve 6 and the insulating sleeve 7 and between the insulating sleeve 7 and the inner roller 8 is an interference fit.

The present invention has been disclosed as above with preferred implementation cases, but it is not intended to limit the present invention. Any skilled person who is familiar with the profession, without departing from the scope of the technical solution of the present invention, does the above implementation cases according to the technical essence of the present invention. Any simple modifications, equivalent changes and modifications still belong to the scope of the technical solution of the present invention.

Claims (7)

1. a kind of multi-layer metal composite plate pulse current assists milling method, it is characterised in that：The method is according to following step Suddenly it realizes：

Step 1：Plank pre-treatment：Treat the punching of rolled plate quadrangle；It polishes surface to be composite, removes plate surface oxide layer And other impurities, remove surface and oil contaminant；

Step 2：Blank is fixed：The clean surface of surface treated sheet metal is overlapped, is penetrated using thin wire reserved Hole in, material is tightened to form composite blank；

Step 3：Electric current auxiliary rolling：Pulse power parameters are adjusted, fixed slab is put into two sets by make pulse power supply Between pulse current assists rolling device, the roller assembly that electric current is flowed into lower section by the roller assembly of top via slab is made to be formed Electric current auxiliary rolling is completed in unicom circuit.

2. a kind of multi-layer metal composite plate pulse current assists milling method according to claim 1, it is characterised in that：Selection Utilize wire brush polishing surface to be composite；It is cleaned by ultrasonic with acetone and ethanol solution, removes surface and oil contaminant.

3. a kind of multi-layer metal composite plate pulse current auxiliary rolling device for realizing milling method described in claims 1 or 2, it Including roller assembly, electrode contact device, conducting wire and the pulse power, it is characterised in that：The roller assembly is three layers of composite junction Structure, including interior roller, insulation sleeve and conductive sleeve, insulation sleeve are nested together with interior roller, and the annular conductive sleeve of installation, leads outside insulation sleeve Electricity, which is put on, is equipped with electrode contact device, and the pulse power contacts device with electrode by conducting wire and connect, and pulse current is via pulse Electrode contact device, the conductive sleeve of topping roll, rolling blank, the conductive sleeve of bottom roll, the lower roll of positive pole, conducting wire, upper roller Electrode contact device, return wire and pulse power cathode, form current loop.

4. a kind of multi-layer metal composite plate pulse current assists rolling device according to claim 3, it is characterised in that：Interior roller For the roll of conventional mill.

5. a kind of multi-layer metal composite plate pulse current assists rolling device according to claim 4, it is characterised in that：Insulation Set is nested together with interior roller interference fit.

6. a kind of multi-layer metal composite plate pulse current assists rolling device according to claim 5, it is characterised in that：Interior roller Be evenly distributed in circumferential lateral surface and be machined with multiple interior roller threaded holes, be evenly distributed in insulation sleeve circumferential lateral surface be machined with it is interior The consistent insulation sleeve countersunk head threaded hole of roller screw thread hole number, interior roller is by being mounted on interior roller threaded hole and insulation sleeve countersunk head screw thread Interior roller insulation sleeve fixing bolt in hole is connect with insulation sleeve.

7. a kind of multi-layer metal composite plate pulse current assists rolling device according to claim 6, it is characterised in that：Insulation Set, which is evenly distributed, is machined with multiple insulation sleeve threaded holes, and conductive sleeve, which is evenly distributed, to be machined with and screw insulator hole number phase one The conductive sleeve countersunk head threaded hole of cause, insulation sleeve pass through the insulation sleeve in insulation sleeve threaded hole and conductive sleeve countersunk head threaded hole Conductive sleeve fixing bolt is connect with conductive sleeve.