CN104294268A - Preparation method of wear-resistant guide roller - Google Patents

Abstract

A method for preparing a wear-resistant guide roller belongs to the technical field of wear-resistant materials. First, the precision casting method is used to manufacture the guide roller body. The chemical composition and mass percentage of the guide roller body are: 0.30～0.45C, 15.0～18.0Cr, 8.0～10.0Mn, 0.30～0.42N, 4.0～5.5Ni, 0.2～0.6 Si, 0.06～0.10Nb, S<0.03, P<0.04, the balance is Fe and unavoidable impurities. After the guide roller body has been roughly machined, a high-hardness wear-resistant cladding layer with a thickness of 1.8-2.5mm is coated on the working surface, so that the service life of the guide roller is greatly improved.

Description

A kind of preparation method of wear-resistant guide roller

technical field

The invention discloses a method for preparing a guide roller, in particular relates to a method for preparing a wear-resistant guide roller, and belongs to the technical field of wear-resistant materials.

Background technique

In the 1960s, the first Morgan 45° high-speed wire rod finishing mill with a new structure came out, which caused a revolutionary change in the wire rod production field. After nearly 40 years of continuous improvement and upgrading, the wire rolling speed has broken through the previous limit and jumped to an astonishing high speed of 120-150m/s. As the rolling speed of the rolling mill increases, the sliding guide device is gradually replaced by a rolling guide (guide roller). Guide rollers are the main consumption tools on high-speed wire rod mills. The annual consumption of guide rollers in the domestic market is more than 5 million pieces, and the annual consumption of guide rollers in the international market is 8-10 million pieces. In addition to the friction of the wire rod, the guide roller is also subjected to the impact of the wire rod, the heating of the high-temperature wire rod and the chilling of the cooling water. The guide roller requires high hardness, high toughness, high thermal fatigue resistance and anti-sticking steel. However, the service life of guide rollers manufactured in my country is relatively low at present, which affects the improvement of steel rolling production efficiency and product qualification rate. In order to improve the performance of the guide roll, the Chinese invention patent CN 103882424 discloses a preparation method of a high-speed wire rod mill guide roll with a laser cladding coating, which is characterized in that the method includes the following steps: a. Selection of the base of the guide roll Bearing steel, medium carbon steel or low alloy steel materials, according to the finished size of the guide roller, use a lathe for rough machining, and leave a finishing allowance of 0.2-0.5mm for each machining surface; b. Rolling surface grooves clad by laser Carry out turning for 0.5-1.5mm cladding margin, and clean the cladding surface; c. configure wear-resistant cladding materials, and select nickel-based or cobalt-based laser cladding powders containing chromium carbide reinforcement materials; d. Use high-power CO2 or YAG or semiconductor or fiber laser to directly feed powder on the surface of the rolling groove for laser cladding scanning. The laser power of YAG laser is 300W-500W, and that of _CO2 , semiconductor and fiber laser is 2000W-4000W. The scanning speed is between 1mm/s-15mm/s, the coating thickness should leave a processing allowance of 0.3mm~0.5mm; e. Finish the rolling guide roller after laser cladding to meet the requirements of dimensional accuracy and surface finish. Chinese invention patent CN 101695713A also discloses a WC composite guide roller and its manufacturing method. The composite guide roller has a composite material layer on the surface of the steel matrix, which is characterized in that the steel matrix is carbon with a carbon content of 0.2 to 0.7% by weight. Steel or alloy steel; the material composition of the composite material layer by weight percentage is: 10-50% of WC, 0.2-0.8% of C, 0-3.0% of Cr, 0-2.0% of Mo, and 0-2.0% of Mn , RE is 0.11-0.5%, the total amount of other metal and non-metal elements is not more than 5%, and the balance is Fe. The composite material powder is coated on the surface of the steel matrix by plasma spraying, and the argon arc remelting method is used to remelt it together with the steel matrix to form a composite material layer on the surface of the steel matrix; or directly apply the composite material powder The body is sprayed on the surface of the steel substrate, and the argon arc remelting method is used to remelt it together with the steel substrate. The composite guide roller of the invention has the advantages of high hardness, good wear resistance, low brittleness, heat treatment, machining, low cost and high cost performance. Chinese invention patent CN 1931462 also discloses a SiC composite guide roller and its manufacturing method, which is characterized in that there is a composite material layer on the surface of the steel matrix, and the material composition of the composite material layer is: SiC5-40%, C0.2-0.6%, 0-3.0% of Cr, 0-2.0% of Mo, 0-2.0% of Mn, the total amount of other metal and non-metal elements is not more than 5%, and the balance is Fe. The composite material powder or wire or rod is coated on the surface of the steel matrix by means of thermal spraying, thermal spray welding or laser cladding to form a bond between the composite material and the steel matrix. The composite guide roller of the invention has excellent properties such as high hardness, good wear resistance, low brittleness, heat treatment, machining, low cost, and high cost performance. Chinese invention patent CN1990906 also discloses a manufacturing technology of high-energy ion implantation of tungsten carbide (WC) gradient materials for guide rolls and sheath rolls in rod and wire rolling mills. Under glow discharge conditions, high-energy tungsten ions and inert gas ions are formed. Firstly, the guide roller or sheathing roller is subjected to gas soft nitriding treatment, and then at a certain temperature, metal tungsten ions are implanted into the surface of the guide roller or sheathing roller, and then the tungsten is carbonized; or firstly, the guide roller or sheathing roller is After the roller set is treated with gas soft nitriding, the double ion high-energy implantation of metal tungsten ions and carbon ions is carried out. This technology can form a certain depth of tungsten carbide alloy layer on the surface of the guide roller or sheathing roller, which increases the hardness of the metal surface and improves the wear resistance, high temperature resistance and self-lubrication of the surface of the guide roller or sheathing roller. The product manufactured by the invention has the advantages of high temperature resistance, high hardness, high strength, high wear resistance, corrosion resistance, etc., and significantly improves the service life of guide rollers or sheathing rollers. Chinese patent 201120010122.0 also discloses a composite wear-resistant rolling steel guide roll, which includes a guide roll base and a wear-resistant coating coated on the surface of the guide roll base. The thickness of the coating is 0.1 mm to 2 mm; A through hole coaxial with the base body of the guide roller is opened. The material of the wear-resistant coating is one of high alloy material or cermet material. The material of the base body of the guide roller is one of high manganese steel, low carbon steel, alloy steel, gray cast iron or ductile iron. The utility model is especially suitable for the rolling guide device of the steel rolling continuous rolling system, and has the advantages of improving the wear resistance, high temperature resistance, thermal shock resistance and other properties of the guide roll, prolonging the service life of the guide roll and reducing the manufacturing cost of the guide roll, etc. .

Contents of the invention

The purpose of the present invention is to overcome the low hardness and poor wear resistance of the above-mentioned guide rollers in the prior art, and provide a laser cladding method on the surface of the low-alloy guide roller, which has high hardness and good high-temperature wear resistance. , Alloy materials with excellent resistance to shock and heat, so as to greatly improve the wear resistance of the guide roller.

Object of the present invention can be realized by following processing steps:

①Firstly, the guide roller body is manufactured by precision casting. The chemical composition and mass percentage of the guide roller body are: 0.30～0.45C, 15.0～18.0Cr, 8.0～10.0Mn, 0.30～0.42N, 4.0～5.5Ni, 0.2～ 0.6Si, 0.06～0.10Nb, S<0.03, P<0.04, the balance is Fe and unavoidable impurities. After sand cleaning and grinding, the cast guide roller body is heated to 1030-1050°C with the furnace, kept warm for 1-2 hours, then water-cooled, and then rough-machined;

② Ferrochrome powder, ferrovanadium powder, ferrotitanium powder, ferroboron powder, ferromolybdenum powder, ferrotungsten powder and pure iron powder are used as ingredients. The above-mentioned powder is 140-200 mesh, and the method of synchronous powder feeding is adopted, and the laser is used for rough processing The wear-resistant cladding layer is prepared on the working surface of the guide roller body. The chemical composition and mass percentage of the wear-resistant cladding layer are: 10.0～10.8Cr, 2.0～2.5V, 0.5～0.8Ti, 1.8～2.2B, 4.5～ 5.2Mo, 6.5～7.0W, 1.20～1.35C, <0.7Si, <0.02S, <0.03P, the balance is Fe and unavoidable impurities.

The laser spot size is 5mm×5mm, the laser head and the powder feeding nozzle are fixed on an industrial robot arm, and the argon gas is passed through to protect the molten pool during cladding, and the thickness of the wear-resistant cladding layer after cladding is 1.8-2.5mm. Finally, finish machining to the specified size and precision of the guide roller to obtain the wear-resistant guide roller. The thickness of the wear-resistant cladding layer of the finished wear-resistant guide roller is 1.5-2.0mm.

The chemical composition and mass percentage of the wear-resistant guide roller body of the present invention are: 0.30-0.45C, 15.0-18.0Cr, 8.0-10.0Mn, 0.30-0.42N, 4.0-5.5Ni, 0.2-0.6Si, 0.06-0.10Nb , S<0.03, P<0.04, the balance is Fe and unavoidable impurities. After the above body material is quenched at 1030-1050°C, an austenite matrix structure with high strength, good toughness and corrosion resistance can be obtained, which can ensure the repeated use of the guide roller body.

On the rough-processed guide roller body, adopt the method of synchronous powder feeding, and use laser cladding to prepare wear-resistant coating, which has a fine and dense structure, and the cladding layer and the guide roller body present a good metallurgical bond, ensuring No cracking and peeling in use. The chemical composition and mass percentage of cladding layer are: 10.0～10.8Cr, 2.0～2.5V, 0.5～0.8Ti, 1.8～2.2B, 4.5～5.2Mo, 6.5～7.0W, 1.20～1.35C, <0.7Si ,<0.02S,<0.03P, the balance is Fe and unavoidable impurities, which can ensure that the cladding layer has high hardness, excellent wear resistance and cold and heat fatigue resistance.

Compared with the prior art, the present invention has the following characteristics:

1) The hardness of the laser cladding layer on the guide roller body of the present invention exceeds 65HRC, and has excellent wear resistance;

2) The guide roller body of the present invention has high strength, good toughness and corrosion resistance, and can be recycled;

3) The service life of the wear-resistant guide roller of the present invention is 3-4 times higher than that of the high-nickel-chromium steel guide roller on a high-speed wire rod mill.

Description of drawings

Figure 1 Structural schematic diagram of wear-resistant guide roller;

1- wear-resistant cladding layer, 2- guide roller body.

Detailed ways

The present invention is further stated below in conjunction with the examples, but the present invention is not limited to the following examples. The structural diagram of the wear-resistant guide roller is shown in Figure 1, and other improved structures are also possible, which is not the key point of the present invention.

Example 1:

The guide roll on the K5 frame of the high-speed wire rolling mill, its preparation process steps are:

①The guide roller body 2 is manufactured by precision casting firstly. The chemical composition and mass percentage of the guide roller body 2 are: 0.32C, 15.07Cr, 9.85Mn, 0.31N, 5.48Ni, 0.27Si, 0.064Nb, 0.021S, 0.033 P, the balance is Fe and unavoidable impurities. After the cast guide roller body 2 is sand-cleaned and polished, it is heated to 1030°C with the furnace, kept warm for 2 hours, then water-cooled, and then rough-machined.

② Use 140-200 mesh ferrochrome powder, vanadium ferro powder, titanium ferro powder, boron ferro powder, molybdenum ferro powder, tungsten ferro powder and pure iron powder as ingredients, adopt the method of synchronous powder feeding, and use a 6kW fiber laser with a wavelength of 1070nm The wear-resistant cladding layer 1 is prepared on the working surface of the guide roller body 2 after rough machining. The chemical composition and mass percentage of the wear-resistant cladding layer 1 are: 10.04Cr, 2.47V, 0.52Ti, 2.19B, 4.51Mo, 6.94 W, 1.23C, 0.38Si, 0.013S, 0.019P, the balance is Fe and unavoidable impurities. The laser spot size is 5mm×5mm. The laser head and powder feeding nozzle are fixed on the arm of an ABB industrial robot. During cladding, argon gas is introduced to protect the molten pool. The thickness of the wear-resistant cladding layer 1 is 1.90mm. Finally, it is finished to The wear-resistant guide roller can be obtained if the size and precision of the guide roller are specified. The thickness of the wear-resistant cladding layer 1 of the finished wear-resistant guide roller is 1.55mm, and the hardness of the wear-resistant cladding layer 1 is 65.6HRC.

Example 2:

The guide roll on the K8 frame of the high-speed wire rolling mill, its preparation process steps are:

①The guide roller body 2 is manufactured by precision casting firstly. The chemical composition and mass percentage of the guide roller body 2 are: 0.44C, 17.73Cr, 8.06Mn, 0.42N, 4.08Ni, 0.55Si, 0.096Nb, 0.025S, 0.037 P, the balance is Fe and unavoidable impurities. After the cast guide roller body 2 is sand-cleaned and polished, it is heated to 1050°C with the furnace, kept warm for 1 hour, then water-cooled, and then rough-machined.

② Use 140-200 mesh ferrochrome powder, vanadium ferro powder, titanium ferro powder, boron ferro powder, molybdenum ferro powder, tungsten ferro powder and pure iron powder as ingredients, adopt the method of synchronous powder feeding, and use a 6kW fiber laser with a wavelength of 1070nm The wear-resistant cladding layer 1 is prepared on the working surface of the guide roller body 2 after rough machining. The chemical composition and mass percentage of the wear-resistant cladding layer 1 are: 10.74Cr, 2.02V, 0.78Ti, 1.81B, 5.17Mo, 6.54 W, 1.32C, 0.40Si, 0.009S, 0.015P, the balance is Fe and unavoidable impurities. The laser spot size is 5mm×5mm. The laser head and powder feeding nozzle are fixed on the arm of an ABB industrial robot. During cladding, argon gas is used to protect the molten pool. The thickness of the wear-resistant cladding layer 1 is 2.4mm. Finally, it is finished to The wear-resistant guide roller can be obtained by the specified size and precision of the guide roller. The thickness of the wear-resistant cladding layer 1 of the finished wear-resistant guide roller is 1.96mm, and the hardness of the wear-resistant cladding layer 1 is 66.1HRC.

Example 3:

The guide roll on the K7 frame of the high-speed wire rolling mill, its preparation process steps are:

①The guide roller body 2 is manufactured by precision casting firstly. The chemical composition and mass percentage of the guide roller body 2 are: 0.39C, 16.70Cr, 8.97Mn, 0.37N, 4.83Ni, 0.21Si, 0.075Nb, 0.020S, 0.027 P, the balance is Fe and unavoidable impurities. After the cast guide roller body 2 is sand-cleaned and polished, it is heated to 1040°C with the furnace, kept warm for 1 hour, then water-cooled, and then rough-machined.

② Use 140-200 mesh ferrochrome powder, vanadium ferro powder, titanium ferro powder, boron ferro powder, molybdenum ferro powder, tungsten ferro powder and pure iron powder as ingredients, adopt the method of synchronous powder feeding, and use a 6kW fiber laser with a wavelength of 1070nm The wear-resistant cladding layer 1 is prepared on the working surface of the guide roller body 2 after rough machining. The chemical composition and mass percentage of the wear-resistant cladding layer 1 are: 10.41Cr, 2.36V, 0.67Ti, 1.98B, 4.72Mo, 6.90 W, 1.26C, 0.46Si, 0.014S, 0.021P, the balance is Fe and unavoidable impurities. The laser spot size is 5mm×5mm. The laser head and powder feeding nozzle are fixed on the arm of an ABB industrial robot. During cladding, argon gas is used to protect the molten pool. The thickness of the wear-resistant cladding layer 1 is 2.1mm. Finally, it is finished to The wear-resistant guide roller can be obtained if the size and precision of the guide roller are specified. The thickness of the wear-resistant cladding layer 1 of the finished wear-resistant guide roller is 1.78mm, and the hardness of the wear-resistant cladding layer 1 is 65.8HRC.

The guide roller of the present invention has been applied industrially on high-speed wire rod mills. The guide roller body has high strength, good toughness and corrosion resistance, and can be recycled. The laser cladding layer on the guide roller body has high hardness and excellent wear resistance. , the service life is 3 to 4 times higher than that of high-nickel-chromium steel guide rollers, and its popularization and application has good economic and social benefits.

Claims (4)

1. a wear-resisting deflector roll preparation method, is characterized in that, comprise the following steps:

1. casting method is first adopted to manufacture deflector roll body, the chemical constitution of deflector roll body and mass percent thereof are: 0.30 ~ 0.45C, 15.0 ~ 18.0Cr, 8.0 ~ 10.0Mn, 0.30 ~ 0.42N, 4.0 ~ 5.5Ni, 0.2 ~ 0.6Si, 0.06 ~ 0.10Nb, S<0.03, P<0.04, surplus is Fe and inevitable impurity; Casting deflector roll body, after sand removal, polishing, is heated to 1030 ~ 1050 DEG C with stove, is incubated water-cooled, subsequently roughing after 1 ~ 2 hour;

2. ferrochrome powder is adopted, vanadium iron powder, titanium-iron powder, ferro-boron powder, molybdenum-iron powder, ferrotungsten powder and straight iron powder batching, above-mentioned powder 140 ~ 200 order, adopt the method for synchronous powder feeding system, wear-resisting cladding layer is prepared with the deflector roll body working-surface of laser apparatus after roughing, the chemical constitution of wear-resisting cladding layer and mass percent thereof are: 10.0 ~ 10.8Cr, 2.0 ~ 2.5V, 0.5 ~ 0.8Ti, 1.8 ~ 2.2B, 4.5 ~ 5.2Mo, 6.5 ~ 7.0W, 1.20 ~ 1.35C, <0.7Si, <0.02S, <0.03P, surplus is Fe and inevitable impurity.

2. according to the method for claim 1, it is characterized in that, during laser melting coating, laser spot size is 5mm × 5mm, and laser head and powder-supplying spray head are fixed in an industrial machine human arm, pass into argon shield molten bath during cladding.

3. according to the method for claim 1, it is characterized in that, the thickness after wear-resisting cladding layer cladding is 1.8 ~ 2.5mm, and be finally refined to dimensions and precision that deflector roll specifies, can obtain wear-resisting deflector roll, the wear-resisting cladding layer thickness of the wear-resisting deflector roll of finished product is 1.5 ~ 2.0mm.

4. according to the wear-resisting deflector roll that the either method of claim 1-3 prepares.