Bimetal wear-resistant plate and preparation method thereof

Abstract

The invention relates to a bimetallic wear-resisting plate which comprises a base plate and a wear-resisting body which are integrally formed by welding, and further comprises a hard phase dispersed and distributed in the wear-resisting body, the wear-resisting body is made of high-chromium alloy, and the hard phase is ceramic particles. The invention further provides a preparation method of the bimetallic wear-resisting plate. The preparation method comprises the steps that S1, alloy powder is weighed according to the proportion and subjected to ball milling and material mixing; s2, mixing the powder with glue: uniformly mixing 100 to 150 milliliters of glue according to 1 kilogram of powder; s3, drying the powder; s4, screening the powder; s5, ceramic particles are added, specifically, the alloy powder and the ceramic particles are added into a zero-gravity mixer together to be fully and evenly mixed, and the ceramic particles account for 5%-15% of the total materials; s6, performing compression molding to obtain a powder prefabricated part; s7, sintering to obtain a wear-resistant body; s8, the wear-resisting body and the base plate are brazed to obtain the bimetallic wear-resisting plate; and S9, a finished product is obtained through grinding, shot blasting and correction. According to the invention, ceramic can be uniformly embedded in the wear-resistant body in the form of particles, so that the service life of the bimetallic wear-resistant plate is greatly prolonged.

Description

Technical Field

[0001] The present invention relates to the technical field of wear-resistant composite of metal materials, and specifically relates to a bimetallic wear-resistant plate and a preparation method thereof. Background Art

[0002] With the progress of technology and the rapid development of the manufacturing industry, especially the continuous increase in labor costs, the requirements for materials are getting higher and higher. At the same time, the requirements for the cost performance of materials are also getting higher and higher, and the requirements for wear resistance and corrosion resistance of parts are also getting more and more stringent. There are many existing preparation methods for wear-resistant plates. Due to limitations in the process or the material itself, it has been very difficult to improve wear resistance, and the cost performance is not high.

[0003] At present, this kind of bimetallic plate is widely used, for example, it is widely used in mines, steel mills, sugar mills, etc.

[0004] At present, for bimetallic plates on the market, carbon steel is generally used as the base plate, and high-chromium cast iron or hard alloy is used as the wear-resistant body, and they are combined through vacuum brazing to finally obtain a bimetallic wear-resistant plate. Products include bimetallic chocolates, bimetallic wear-resistant liners, bimetallic runner plates, etc. The wear resistance of these bimetallic plates actually still depends on the performance of the wear-resistant body material.

[0005] There are also cases where crushed particles of hard alloy are poured into high-chromium cast iron and added to the casting with the molten iron during pouring to improve the wear resistance of the casting. However, due to the randomness of the particles and the specific gravity problem of the particles, the service life of this kind of casting will eventually be unstable due to the uneven distribution of the particles.

[0006] In addition, when traditional high-chromium cast iron is inlaid with ceramic particles, the ceramic particles are made into prefabricated parts and then inlaid into the casting of high-chromium cast iron in the form of prefabricated parts. As described in Patent CN 113714488 A, this technology has two limitations. First, there are great limitations on the size of the casting or the wall thickness of the casting. Due to the limitations of the wall thickness, size, etc., the wear-resistant body required for the bimetallic plate cannot cast a wear-resistant body containing ceramic particles. Second, there is a minimum distance limit for the interval between the casting and the prefabricated part, generally 20mm - 30mm. This limitation makes the wear-resistant body formed by casting the inlaid part containing the prefabricated part unable to be applied in the bimetallic wear-resistant plate. The present invention can solve this limitation through the change of the forming process. Summary of the Invention

[0007] In view of the above problems, the present invention provides a bimetallic wear-resistant plate in which ceramic particles are evenly inlaid in the wear-resistant body, improving the service life.

[0008] The technical solution adopted by the present invention to solve the above technical problems is as follows: A bimetallic wear-resistant plate includes a substrate, a wear-resistant body, and hard phases dispersed in the wear-resistant body. The wear-resistant body and the substrate are integrally formed by brazing. The material of the wear-resistant body is high-chromium alloy, and the hard phases are ceramic particles.

[0009] The present invention also provides a preparation method for a bimetallic wear-resistant plate, including the following steps:

[0010] S1, Ball milling and mixing: Weigh and mix alloy powder materials in proportion, and perform sufficient ball milling and mixing in a ball mill;

[0011] S2, Powder doping with glue: Mix 100 - 150 milliliters of glue per 1 kilogram of powder materials evenly in a doping machine;

[0012] S3, Powder drying: Place the alloy powder materials doped with glue in an air-drying chamber and dry them by blowing air with a blower;

[0013] S4, Powder screening: Place the dried alloy powder materials in a sieve and sieve them through a 30-mesh sieve;

[0014] S5, Adding ceramic particles: Reserve 10% - 20% of the dried alloy powder materials, and add the remaining alloy powder materials and ceramic particles together to a gravity-free mixer for sufficient mixing. The ceramic particles account for 5% - 15% of the total materials;

[0015] S6, Compression molding: Weigh the materials prepared in step S5 as needed, put them into a wear-resistant body mold, and press them into shape under a molding hydraulic press to obtain a powder preform;

[0016] S7, Sintering: Degrease and sinter the powder preform in a vacuum high-temperature furnace to form the final required alloy product, the wear-resistant body;

[0017] S8, Welding: Brazing the sintered wear-resistant body and the substrate to form a bimetallic wear-resistant plate;

[0018] S9, Obtaining the finished product: Grind, shot blast, and correct the welded bimetallic plate to obtain the finished product.

[0019] Preferably, the alloy powder materials in step S1 are prepared into powder by the following weight percentages: Cr: 20 - 30%, C: 2.5 - 4.5%, Mo: 0.3 - 3.0%, Cu: 0.3 - 1.0%, Mn: 0 - 1.0%, Si: 0 - 1.5%, Zr: 0 - 0.5%, TiC: 0 - 3.0%, BC: 0 - 3.0%, and the balance is Fe and unavoidable impurities.

[0020] Preferably, the step S6 is specifically as follows: Take a wear-resistant body mold, add a reserved layer of alloy powder to the bottom surface of the mold, place it in a quantitative material frame, then add alloy powder with ceramic particles, take out the quantitative material frame, and finally add another reserved layer of alloy powder, and press and form it using a molding hydraulic press.

[0021] Preferably, the step S8 is specifically to pair the sintered wear-resistant body with the substrate, and at the same time add a copper sheet with a thickness of 0.2 mm to 0.4 mm between the wear-resistant body and the substrate, and finally weld and form it in a vacuum furnace.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The present invention can uniformly embed ceramics in the form of particles in the wear-resistant body, solve the problems that the wear-resistant body required for the bimetallic plate is limited by wall thickness, size, etc., and is more easily realized economically and with quality assurance;

[0024] 2. Under the same working conditions, the wear resistance of the bimetallic plate prepared by the present invention is significantly improved, so the service life is equally improved, generally 150% - 300% of the service life of conventional products. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a schematic diagram of the first welding structure of the bimetallic wear-resistant plate of the present invention;

[0026] Figure 2 is a schematic diagram of the second welding structure of the bimetallic wear-resistant plate of the present invention;

[0027] Figure 3 is a schematic diagram of the third welding structure of the bimetallic wear-resistant plate of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] The following will be combined with Figures 1 - 3 to describe the present invention in detail. Here, the schematic embodiments of the present invention and the descriptions are used to explain the present invention, but not to limit the present invention.

[0029] A bimetallic wear-resistant plate includes a substrate 2, a wear-resistant body 1, and a hard phase 3 dispersed in the wear-resistant body. The wear-resistant body and the substrate are integrally formed by brazing. There is a welding joint 4 reserved between the wear-resistant body and the substrate, and the welding joint is a welding surface or a flux layer. The material of the wear-resistant body is a high-chromium alloy, and the hard phase is ceramic particles.

[0030] Among them, the matrix material alloy powder of the wear-resistant body is mainly based on chromium and iron as the main matrix, including molybdenum, titanium carbide, manganese, copper, carbon, boron carbide, etc. and some inevitable impurities. The components are shown in Table 1 below:

[0031] Component Chromium / Cr Iron / Fe Carbon / C Molybdenum / Mo Copper / Cu Mass % 20-30 Balance 2.5-4.5 0.30-3.00 0.30-1.00 Component Manganese / Mn Silicon / Si Zirconium / Zr Titanium Carbide / TiC Boron Carbide / BC Mass % 0-1.0 0-1.5 0-0.5 0-3.0 0-3.0

[0032] Table 1

[0033] The different proportions of materials depend on the working conditions' requirements for material wear resistance, corrosion resistance, impact resistance, etc.

[0034] In order to evenly mix the matrix material and the ceramic particles into a mold, a molding step is required (the molding process or steps for different raw materials may be slightly different, see the implementation case for details).

[0035] A method for preparing a bimetallic wear-resistant plate comprises the following steps:

[0036] S1, ball milling and mixing: weigh the alloy powders according to proportion and mix them together, and then ball mill them in a ball mill to mix them thoroughly;

[0037] S2, powder mixed with glue: 100-150 ml glue for 1 kg powder, mix evenly in glue mixing machine;

[0038] S3, powder drying: put the alloy powder mixed with glue in the air drying room and dry it with a fan;

[0039] S4, powder screening: put the dried alloy powder into a 30-mesh sieve;

[0040] S5, adding ceramic particles: reserve 10%-20% of the dried alloy powder, add the remaining alloy powder and ceramic particles into the zero-gravity mixer and mix them evenly. Generally, ceramic particles account for 5%-15% of the total material. The amount of ceramic particles added depends on the wear-resistant requirements of the working conditions;

[0041] S6, pressing and molding: take a wear-resistant body mold, weigh the material prepared in step S5 as needed, put it into the wear-resistant body mold, first add a layer of reserved alloy powder on the bottom of the mold, put it into a quantitative material frame, then add alloy powder with ceramic particles, take out the quantitative material frame, and finally add another layer of reserved alloy powder, use a 600T molding hydraulic press to press and mold, and obtain a powder preform;

[0042] S7, sintering: degreasing and sintering the powder preform in a vacuum high-temperature furnace to form the final desired alloy product wear-resistant body;

[0043] S8, welding: pair the sintered wear-resistant body with the substrate, and add a 0.2mm-0.4mm copper sheet between the wear-resistant body and the substrate, and finally weld them in a vacuum furnace to form a bimetallic wear-resistant plate;

[0044] S9, obtaining the finished product: the welded bimetallic plates are polished, shot blasted and corrected to obtain the finished product.

[0045] Example 1

[0046] The bimetallic plate structure of this embodiment is as followsFigure 1 As shown, the wear-resistant body is formed by powder metallurgy, and a welding surface is reserved on one side of the wear-resistant body.

[0047] The material ratios used in this embodiment are shown in Table 2 below:

[0048] Component Chromium / Cr Iron / Fe Carbon / C Molybdenum / Mo Copper / Cu Mass % 20-22 Balance 3.0-3.5 0.30-0.5 0.30-0.50 Component Manganese / Mn Silicon / Si Zirconium / Zr Titanium Carbide / TiC Boron Carbide / BC Mass % 0.3-0.5 0.4-0.6 0.01-0.02 1.0-2.0 0

[0049] Table 2

[0050] Note 1: The chromium, molybdenum, manganese, silicon and zirconium required in this embodiment are prepared by crushing and sieving ferroalloy to 200-500 meshes respectively for batching;

[0051] Note 2: The copper, titanium carbide and iron required for this embodiment are purchased as 300 mesh finished powders;

[0052] The preparation method of this embodiment is:

[0053] S1, ball milling and mixing: weigh the alloy powders according to proportion and mix them together, and then ball mill them in a ball mill to mix them thoroughly;

[0054] S2, powder mixed with glue: 1 kg powder with 100 ml glue, mix evenly in a glue mixing machine;

[0055] S3, powder drying: spread the alloy powder mixed with glue on a stainless steel plate, place it in an air drying room, and air dry it with a fan;

[0056] S4, powder screening: put the dried alloy powder into a 30-mesh sieve;

[0057] S5, adding ceramic particles: reserve 10% of the dried alloy powder, weigh the remaining alloy powder, and weigh ceramic particles according to 5% of the remaining alloy powder, and mix them thoroughly in a zero-gravity mixer for about 1 hour to ensure that the alloy powder is fully coated on the surface of the particles;

[0058] S6, pressing and molding: take a wear-resistant body mold, weigh the material prepared in step S5 as needed, put it into the wear-resistant body mold, first add a layer of reserved alloy powder on the bottom of the mold, put it into a quantitative material frame, then add alloy powder with ceramic particles, take out the quantitative material frame, and finally add another layer of reserved alloy powder, use a 600T molding hydraulic press to press and mold, and obtain a powder preform;

[0059] S7, sintering: the powder preforms are placed in layers into a vacuum high-temperature degreasing furnace, the degreasing and sintering curves are set, and finally sintered at 1200-1300°C to form the final desired alloy product wear-resistant body;

[0060] S8, welding: pair the sintered wear-resistant body with the substrate, and add a 0.2mm-0.4mm copper sheet between the wear-resistant body and the substrate, and finally weld them in a vacuum furnace to form a bimetallic wear-resistant plate;

[0061] S9, obtaining the finished product: the welded bimetallic plate is polished, shot blasted and corrected to obtain the finished product.

[0062] Example 2

[0063] The bimetallic plate structure of this embodiment is as follows Figure 2 As shown, the wear-resistant body is formed by powder metallurgy, and a welding surface is reserved between the wear-resistant body and the substrate. In order to maintain the beauty of the wear-resistant body, pure powder metallurgy layers are reserved on the other three surfaces.

[0064] The material ratios used in this embodiment are shown in Table 3 below:

[0065]

[0066]

[0067] Table 3

[0068] Description 1: The chromium, molybdenum, manganese, silicon, copper, iron and zirconium required in this embodiment are prepared into molten steel in a medium frequency electric furnace, then atomized to >200 mesh, and then mixed with other materials;

[0069] Note 2: The titanium carbide and boron carbide required in this embodiment are 300-mesh finished powders;

[0070] The preparation method of this embodiment is:

[0071] S1, ball milling and mixing: weigh the alloy powders according to proportion and mix them together, and then ball mill them in a ball mill to mix them thoroughly;

[0072] S2, powder mixed with glue: 1 kg powder with 120 ml glue, mix evenly in a glue mixing machine;

[0073] S3, powder drying: spread the alloy powder mixed with glue on a stainless steel plate, place it in an air drying room, and air dry it with a fan;

[0074] S4, powder screening: put the dried alloy powder into a 30-mesh sieve;

[0075] S5, adding ceramic particles: reserve 15% of the dried alloy powder, weigh the remaining alloy powder, and weigh ceramic particles according to 10% of the remaining alloy powder, and fully mix them in a zero-gravity mixer for about 2 hours to ensure that the alloy powder is fully coated on the surface of the particles;

[0076] S6, pressing and molding: take a wear-resistant body mold, weigh the material prepared in step S5 as needed, put it into the wear-resistant body mold, first add a layer of reserved alloy powder on the bottom of the mold, put it into a quantitative material frame, then add alloy powder with ceramic particles, take out the quantitative material frame, and finally add another layer of reserved alloy powder, use a 600T molding hydraulic press to press and mold, and obtain a powder preform;

[0077] S7, sintering: the powder preforms are placed in layers in a vacuum high-temperature degreasing furnace, the degreasing and sintering curves are set, and finally sintered at 1250-1350°C to form the final desired alloy product wear-resistant body;

[0078] S8, welding: pair the sintered wear-resistant body with the substrate, and add a 0.2mm-0.4mm copper sheet between the wear-resistant body and the substrate, and finally weld them in a vacuum furnace to form a bimetallic wear-resistant plate;

[0079] S9, obtaining the finished product: the welded bimetallic plates are polished, shot blasted and corrected to obtain the finished product.

[0080] Example 3

[0081] The bimetallic plate structure of this embodiment is as follows Figure 3 As shown, the wear-resistant body is formed by powder metallurgy, and a flux layer is provided between the wear-resistant body and the substrate.

[0082] The material ratios used in this embodiment are shown in Table 4 below:

[0083] Component Chromium / Cr Iron / Fe Carbon / C Molybdenum / Mo Copper / Cu Mass % 24-25 Balance 3.0-3.4 2.5-3.0 0.30-0.50 Component Manganese / Mn Silicon / Si Zirconium / Zr Titanium Carbide / TiC Boron Carbide / BC Mass % 0.6-0.9 0.4-0.8 / 2.0-3.0 2.0-3.0

[0084] Table 4

[0085] 1: The chromium, molybdenum, manganese, silicon, copper, iron and zirconium required in this embodiment are prepared into molten steel in a medium frequency electric furnace, then atomized to >200 mesh, and then mixed with other materials;

[0086] Note 2: The titanium carbide and boron carbide required in this embodiment are 300-mesh finished powders;

[0087] The preparation method of this embodiment is:

[0088] S1, ball milling and mixing: weigh the alloy powders according to proportion and mix them together, and then ball mill them in a ball mill to mix them thoroughly;

[0089] S2, powder mixed with glue: 150 ml glue for 1 kg powder, mix evenly in a glue mixing machine;

[0090] S3, powder drying: spread the alloy powder mixed with glue on a stainless steel plate, place it in an air drying room, and air dry it with a fan;

[0091] S4, powder screening: put the dried alloy powder into a 30-mesh sieve;

[0092] S5, adding ceramic particles: reserve 20% of the dried alloy powder, weigh the remaining alloy powder, and weigh ceramic particles according to 15% of the remaining alloy powder, and fully mix them in a zero-gravity mixer for about 2 hours to ensure that the alloy powder is fully coated on the surface of the particles;

[0093] S6, pressing and molding: take a wear-resistant body mold, weigh the material prepared in step S5 as needed, put it into the wear-resistant body mold, first add a layer of reserved alloy powder on the bottom of the mold, put it into a quantitative material frame, then add alloy powder with ceramic particles, take out the quantitative material frame, and finally add another layer of reserved alloy powder, use a 600T molding hydraulic press to press and mold, and obtain a powder preform;

[0094] S7, sintering: the powder preforms are placed in layers into a vacuum high-temperature degreasing furnace, the degreasing and sintering curves are set, and finally sintered at 1300-1400°C to form the final desired alloy product wear-resistant body;

[0095] S8, welding: pair the sintered wear-resistant body with the substrate, and add a 0.2mm-0.4mm copper sheet between the wear-resistant body and the substrate, and finally weld them in a vacuum furnace to form a bimetallic wear-resistant plate;

[0096] S9, obtaining the finished product: the welded bimetallic plates are polished, shot blasted and corrected to obtain the finished product.

[0097] The bimetallic wear-resistant bodies obtained in Example 1, Example 2, and Example 3 were all subjected to weld fracture tests using welding specimens with a cross-sectional size of 50 mm×50 mm. The welding strengths of the obtained bimetallic wear-resistant bodies are shown in Table 5 below:

[0098] Specimen Specimen Size Crushing Strength Example 1 Cr20 50mm × 50mm 150 Mpa Example 2 Cr28 50mm × 50mm 120 Mpa Example 3 Cr25 50mm × 50mm 150 MPa Conventional Cast Wear-Resistant Body 50mm × 50mm 60 Mpa

[0099] Table 5

[0100] It can be seen from Table 5 that the wear-resistant body produced by the preparation method of the present invention has a much higher breaking strength than the conventional cast wear-resistant body, and thus the service life of the wear-resistant body produced by the preparation method is much higher than the conventional cast wear-resistant body.

[0101] At the same time, the bimetallic wear-resistant bodies obtained in Example 1, Example 2, and Example 3 were subjected to wear tests with conventional cast wear-resistant bodies, and the wear conditions were as follows:

[0102] Test machine model: MLD-10; Test method: rotation; Test temperature: room temperature; Wear time: 4320 minutes; Test specifications: flat 40×15×5;

[0103] The wear test results are shown in Table 6 below.

[0104]

[0105] Table 6

[0106] The hardness of the wear-resistant body obtained in Example 1 is equivalent to that of the conventional cast wear-resistant body, both being 60-64 HRc. However, due to the uniformly distributed hard phases (ceramic particles) in the wear-resistant body of the present invention, the wear resistance is significantly improved under the same working conditions, being 150%-200% or more of the life of the conventional product;

[0107] The hardness of the wear-resistant body obtained in Example 2 is 62-67 HRc. At the same time, due to the increase in the addition amount of the hard phase (ceramic particles), the wear resistance under the same working conditions is 200%-300% of the life of the conventional product, and some are more than 300%;

[0108] The wear-resistant body obtained in Example 3 has a hardness of 63-65 HRc. While adding the hard phase (ceramic particles), TiC and BC are added to the matrix material to improve the wear resistance of the wear-resistant body matrix. Its actual service life under the same working conditions is more than 300% of the conventional product.

[0109] The technical solutions provided by the embodiments of the present invention have been introduced in detail above. Specific examples are used in this article to elaborate on the principles and implementation manners of the embodiments of the present invention. The descriptions of the above embodiments are only applicable to help understand the principles of the embodiments of the present invention; at the same time, for those of ordinary skill in the art, according to the embodiments of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A bimetallic wear-resistant plate, characterized in that: It comprises a substrate (2), a wear-resistant body (1) and a hard phase (3) dispersed in the wear-resistant body, wherein the wear-resistant body and the substrate are integrally formed by brazing, the wear-resistant body is made of a high-chromium alloy, and the hard phase is ceramic particles.

2. A method for preparing a bimetallic wear-resistant plate, characterized in that: The following steps are involved: S1, ball milling and mixing: weigh the alloy powders according to proportion and mix them together, and then ball mill them in a ball mill to mix them thoroughly; S2, powder mixed with glue: 100-150 ml glue for 1 kg powder, mix evenly in glue mixing machine; S3, powder drying: put the alloy powder mixed with glue in the air drying room and dry it with a fan; S4, powder screening: put the dried alloy powder into a 30-mesh sieve; S5, adding ceramic particles: reserve 10%-20% of the dried alloy powder, add the remaining alloy powder and ceramic particles together into a zero-gravity mixer and mix them evenly, wherein the ceramic particles account for 5%-15% of the total material; S6, pressing and molding: weigh the material prepared in step S5 as required, put it into a wear-resistant body mold, and press and mold it under a molding hydraulic press to obtain a powder preform; S7, sintering: degreasing and sintering the powder preform in a vacuum high-temperature furnace to form the final desired alloy product wear-resistant body; S8, welding: brazing the sintered wear-resistant body and the substrate to form a bimetallic wear-resistant plate; S9, obtaining the finished product: the welded bimetallic plates are polished, shot blasted and corrected to obtain the finished product.

3. The method for preparing the bimetallic wear-resistant plate according to claim 2, characterized in that: The alloy powder in step S1 is prepared into powder by the following weight percentages: Cr: 20-30%, C: 2.5-4.5%, Mo: 0.3-3.0%, Cu: 0.3-1.0%, Mn: 0-1.0%, Si: 0-1.5%, Zr: 0-0.5%, TiC: 0-3.0%, BC: 0-3.0%, and the balance is Fe and unavoidable impurities.

4. The method for preparing the bimetallic wear-resistant plate according to claim 2, characterized in that: The step S6 specifically comprises taking a wear-resistant body mold, adding a layer of reserved alloy powder on the bottom surface of the mold, putting in a quantitative material frame, adding alloy powder with ceramic particles, taking out the quantitative material frame, and finally adding another layer of reserved alloy powder, and pressing and molding using a molding hydraulic press.

5. The method for preparing the bimetallic wear-resistant plate according to claim 2, characterized in that: The step S8 specifically includes pairing the sintered wear-resistant body with the substrate, adding a 0.2 mm to 0.4 mm copper sheet between the wear-resistant body and the substrate, and finally welding them in a vacuum furnace.

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