Preparation method of novel high-entropy alloy powder for diamond tool

Abstract

The invention discloses a preparation method of novel high-entropy alloy powder for a diamond tool. Wherein the requirements for wettability, high temperature resistance and wear resistance are taken as traction, and alloy elements are screened and classified step by step. The novel eutectic high-entropy alloy system with the high elastic modulus is obtained by referring to phase equilibrium state standards, assisting phase diagram calculation and combining high-throughput design, preparation and characterization methods to feed back and adjust the design thought of the eutectic alloy system. And thus, the FCC / Laves double-phase high-entropy alloy system is obtained. According to the high-entropy alloy casting obtained through the design method, a face-centered cubic (FCC) and close-packed hexagonal (Laves) biphase eutectic structure is achieved, and the comprehensive performance of the high-entropy alloy casting can be stably improved by 60% or above compared with that of an existing product of the same grade in the high-temperature environment of 600-1000 DEG C. The elasticity modulus of a high-entropy alloy powder sintered body can reach 655 N / mm < 2 > or above, the plastic elongation rate of the high-entropy alloy powder sintered body can be controlled to be 1.5% or below, and the average cutting efficiency and the average cutting life are improved by 50% and 60% respectively. According to the method, alloy powder products which are required by current production and have excellent comprehensive performance can be efficiently obtained on the premise that the balance of low consumption, low cost and equivalent performance replacement is met, and the method has very important reference value for design and application of novel eutectic high-entropy alloy for subsequent diamond tools.

Description

Technical Field

[0001] The invention belongs to the technical field of preparation of novel high entropy alloy powder for diamond tools, and in particular relates to establishing and improving a microstructure and performance relationship model of a novel diamond tool. Background Art

[0002] With the improvement of engineering technology requirements in today's social production, people adhere to the major strategic goal of "sustainable development" and strive to develop green and low-consumption industrial products. It is understood that the commonly used materials for diamond tools are cobalt metal matrix + diamond composite materials, but the overall cost is high. Some manufacturers have tried to replace cobalt metal with low-cost iron and other alloys, but the weak high temperature resistance, low cutting efficiency and cutting life of diamond tool products are the main reasons for their easy failure in production environments, and seriously restrict the development of related industries in my country. In recent years, with the continuous transformation and upgrading of national industrial technology and the publication of advanced material guidelines, diamond tool (especially high-end products) materials have provided long-term and huge development space.

[0003] In order to overcome the limitations of traditional alloys in terms of the difficulty in balancing low consumption and low cost and equivalent performance, the recently emerging high entropy alloys (HEAs) have provided a new way for the development of diamond tools. In particular, the unique "cocktail effect" (i.e., designability) of high entropy alloys themselves makes it possible for the metal matrix of high-end diamond tools to break the above limitations. In addition, the entire process of high entropy alloy powder is simple, convenient, and stable and repeatable. Its sintered body has a high elastic modulus and low plastic elongation, and has good wettability for diamond, which is expected to obtain more stable comprehensive performance in existing products of the same grade. The establishment and improvement of the theoretical design of new high entropy alloy powder for diamond tools can address the problem that there is a lack of corresponding theoretical support for the relationship between the composition and microstructure of high entropy alloys and the performance of diamond tools.

[0004] The present invention utilizes the designability of high entropy alloys to develop and prepare new high entropy alloy systems: based on the requirements of wettability, high temperature resistance, and wear resistance, alloy elements are screened and classified, and the traditional phase structure criteria and the calculation of "eutectic plane" are referred to. The design ideas of the eutectic alloy system are adjusted by combining the high-throughput design, preparation and characterization methods, and finally a new eutectic high entropy alloy system with high elastic modulus is obtained based on the elastic modulus as the main screening basis. The high temperature oxidation resistance and wear resistance of the designed eutectic high entropy alloy material component system are preliminarily explored and integrated, and the optimal system eutectic high entropy alloy is used to prepare powder materials by gas atomization, and a model of the relationship between powder morphology and gas atomization process is established. Based on the high-entropy alloy with the optimal high elastic modulus, a new diamond tool sample is obtained by high-throughput by adjusting the ratio of diamond to alloy matrix, and the sintering process is optimized to form a process database for sintering and preparing new diamond tools. In the face of high-end diamond tools, this invention is expected to optimize and improve the design theory of high entropy alloy systems and obtain low-cost, high-performance metal matrices. It also establishes a microscopic connection between the metal matrix and the diamond, providing theoretical support for obtaining high-performance diamond tools, which is of great reference value for the subsequent market promotion and application of diamond tools. Summary of the invention

[0005] 1. A method for preparing a new type of high entropy alloy powder for diamond tools, characterized in that it comprises the following steps:

[0006] (1) According to the requirements of diamond tools for "wettability", "wear resistance" and "high temperature resistance", alloy elements (Fe, Co, Cr, Ni, Cu, W, C) are selected. In order to obtain a stable solid solution high entropy alloy, the range of elements in the dual-phase high entropy alloy is clarified by using the traditional phase structure criterion, and the "eutectic surface" of the wear-resistant alloy system is obtained by combining the extrapolation method and phase diagram calculation. A new eutectic high entropy alloy system for high-end diamond tools is initially obtained.

[0007] (2) For the eutectic high entropy alloy system in step (1), a high-throughput casting verification experiment was performed using differential scanning calorimetry (DSC). The purity of the high entropy alloy powder was 99.0-99.5%, and the particle size was 50-80 μm. It was prepared in a suspension melting furnace, protected by high-purity argon gas, and the melting process was repeated 4 times to ensure uniform composition of the cast alloy.

[0008] (3) Based on the relationship between the composition and structure of the quasi-eutectic high entropy alloy casting in step (2), the two-phase composition is further optimized to achieve feedback adjustment of the original design method, thereby obtaining a new high-temperature eutectic high entropy alloy system.

[0009] (4) For the high entropy alloy obtained in step (3), a high elastic modulus eutectic high entropy alloy system is obtained using "elastic modulus" as a screening criterion.

[0010] (5) Preliminary study of the wear resistance of the new eutectic high entropy alloy under conditions such as relative hardness, geometric characteristics of abrasives, load, and sliding speed, and screen out the optimal wear-resistant eutectic high entropy alloy system in step (4).

[0011] (6) Systematically explore the gas atomization process to obtain eutectic high-entropy alloy powder with excellent particle morphology.

[0012] 2. A new type of eutectic high entropy alloy designed according to the method described in claim 1, characterized in that the designed eutectic high entropy alloy casting realizes a dual-phase eutectic structure of face-centered cubic (FCC) and hexagonal close-packed (Laves), and the eutectic width is 0.598~0.725μm.

[0013] 3. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the performance of the eutectic high entropy alloy casting obtained by the design is better than that of traditional diamond alloy powder; and the comprehensive performance can be stably improved by more than 60% compared with existing products of the same grade, and it can better meet the selection of material structure and mechanical properties in terms of wear resistance, high temperature resistance or actual specific environment.

[0014] 4. A novel eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the eutectic high entropy alloy sintered body designed has a high elastic modulus (≥650N / mm 2 ) and low plastic elongation (≤1.5%), and has good wettability to diamond.

[0015] 5. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that the average cutting efficiency and average cutting life of the diamond tool sintered body are increased by 50% and 60% respectively.

[0016] The new eutectic high entropy alloy powder for high-end diamond tools designed by the method of the present invention has the following advantages:

[0017] By utilizing the designability of high entropy alloys to develop new high entropy alloy systems and prepare powders, we can overcome the limitations of traditional alloys in terms of low consumption, low cost and performance equivalent replacement, thereby improving the low-cost performance of diamond tool sintered bodies. This method has flexible design steps, high product utilization, and high work efficiency, which is conducive to promoting the market competition of new products.

[0018] In addition, the present invention combines a large number of theoretical calculations, phase diagram calculations, microstructure characterization, mechanical properties testing, etc., to obtain rich experimental data and establish a systematic new material design theory; on the other hand, the preparation process, microstructure, and performance results of the new diamond tool are fully characterized and tested, building an intrinsic connection between microstructure and macroscopic performance, further enriching the design theory of new materials; finally, the high elastic modulus Fe-Co-Cr-Ni-Cu-WC eutectic high entropy alloy optimized diamond tool developed in this project has good comprehensive properties such as wear resistance and high temperature resistance, and can be applied to metallurgy, electricity, coal, machinery and other industries, with high industrial value. DETAILED DESCRIPTION

[0019] Implementation Method 1

[0020] 1. A method for preparing a new type of high entropy alloy powder for diamond tools, characterized in that it comprises the following steps:

[0021] (1) According to the requirements of diamond tools for "wettability", "wear resistance" and "high temperature resistance", alloy elements (Fe, Co, Cr, Ni, Cu, W, C) were selected. In order to obtain a stable solid solution high entropy alloy, the range of elements in the dual-phase high entropy alloy was clarified using the traditional phase structure criterion, and the "eutectic surface" of the wear-resistant alloy system was obtained by combining the extrapolation method and phase diagram calculation. A new high entropy alloy system FeCoCrNiCu with a dual-phase structure for diamond tools was initially obtained. 1.5 W 0.2 C 0.9 .

[0022] (2) For the eutectic high entropy alloy system in step (1), a high-throughput casting verification experiment was performed using differential scanning calorimetry (DSC). The purity of the high entropy alloy powder was 99.0-99.5%, and the particle size was 50-80 μm. It was prepared in a suspension melting furnace, protected by high-purity argon gas, and the melting process was repeated 4 times to ensure uniform composition of the cast alloy.

[0023] (3) For the quasi-eutectic high entropy alloy casting FeCoCrNiCu in step (2) 1.5 W 0.2 C 0.9 , further increase the content of FCC phase, adjust the associated elements Ni and Cr of the original phase structure, and thus obtain a new high-temperature eutectic high-entropy alloy system FeCoNi 2.0 Cr 1.2 Cu 1.5 W 0.2 C 0.9 .

[0024] (4) For the high entropy alloy obtained in step (3), its elastic modulus is about 712N / mm2 .

[0025] (5) For the high entropy alloy obtained in step (3), its relative hardness is: FeCoNi under the conditions of abrasive geometric characteristics, load, sliding speed, etc. 2.0 Cr 1.2 Cu 1.5 W 0.2 C 0.9 The wear rate is 5.65×10 -5 mm 3 / N·m.

[0026] (6) In order to obtain eutectic high entropy alloy powder with excellent particle morphology, the specific gas atomization process is as follows: gas flow rate 0.20m 3 / s, melt flow rate 65kg / min, air pressure 0.6MPa, gas flow rate 55m / s.

[0027] 2. A new type of eutectic high entropy alloy designed according to the method described in claim 1, characterized in that the designed eutectic high entropy alloy casting realizes a dual-phase eutectic structure of face-centered cubic (FCC) and hexagonal close-packed (Laves), and the eutectic width is 0.647μm.

[0028] 3. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the performance of the eutectic high entropy alloy casting obtained by the design is better than that of traditional diamond alloy powder; and the comprehensive performance can be stably improved by more than 60% compared with existing products of the same grade, and it can better meet the selection of material structure and mechanical properties in terms of wear resistance, high temperature resistance or actual specific environment.

[0029] 4. A novel eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the eutectic high entropy alloy sintered body designed has a high elastic modulus (=712N / mm 2 ≥650N / mm 2 ) and low plastic elongation (=1.25%≤1.5%), and has good wettability to diamond.

[0030] 5. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that the average cutting efficiency and average cutting life of the diamond tool sintered body are increased by 50% and 60% respectively.

[0031] Implementation Method 2

[0032] 1. A method for preparing a new type of high entropy alloy powder for diamond tools, characterized in that it comprises the following steps:

[0033] (1) According to the requirements of diamond tools for "wettability", "wear resistance" and "high temperature resistance", alloy elements (Fe, Co, Cr, Ni, Cu, W, C) were selected. In order to obtain a stable solid solution high entropy alloy, the range of elements in the dual-phase high entropy alloy was clarified using the traditional phase structure criterion, and the "eutectic surface" of the wear-resistant alloy system was obtained by combining the extrapolation method and phase diagram calculation. A new high entropy alloy system FeCoCrNiCu with a dual-phase structure for diamond tools was initially obtained. 1.5 W 0.2 C 0.9 .

[0034] (2) For the eutectic high entropy alloy system in step (1), a high-throughput casting verification experiment was performed using differential scanning calorimetry (DSC). The purity of the high entropy alloy powder was 99.0-99.5%, and the particle size was 50-80 μm. It was prepared in a suspension melting furnace, protected by high-purity argon gas, and the melting process was repeated 4 times to ensure uniform composition of the cast alloy.

[0035] (3) For the quasi-eutectic high entropy alloy casting FeCoCrNiCu in step (2) 1.5 W 0.2 C 0.9 , further increase the content of FCC phase, adjust the associated elements Ni and Cr of the original phase structure, and thus obtain a new high-temperature eutectic high-entropy alloy system FeCoNi 2.0 Cr 1.2 Cu 1.5 W 0.2 C 0.63 .

[0036] (4) For the high entropy alloy obtained in step (3), its elastic modulus is about 680N / mm 2 .

[0037] (5) For the high entropy alloy obtained in step (3), its relative hardness is: FeCoNi under the conditions of abrasive geometric characteristics, load, sliding speed, etc. 2.0 Cr 1.2 Cu 1.5 W 0.2 C 0.63 The wear rate is 6.68mm 3 / N·m.

[0038] (6) In order to obtain eutectic high entropy alloy powder with excellent particle morphology, the specific gas atomization process is as follows: gas flow rate 0.14m 3 / s, melt flow rate 55kg / min, air pressure 0.6MPa, gas flow rate 55m / s.

[0039] 2. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that the designed eutectic high entropy alloy casting realizes a dual-phase eutectic structure of face-centered cubic (FCC) and hexagonal close-packed (Laves), and the eutectic width is 0.549μm.

[0040] 3. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the performance of the eutectic high entropy alloy casting obtained by the design is better than that of traditional diamond alloy powder; and the comprehensive performance can be stably improved by more than 60% compared with existing products of the same grade, and it can better meet the selection of material structure and mechanical properties in terms of wear resistance, high temperature resistance or actual specific environment.

[0041] 4. A novel eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the eutectic high entropy alloy sintered body designed has a high elastic modulus (=680N / mm 2 ≥650N / mm 2 ) and low plastic elongation (=1.36%≤1.5%), and has good wettability for diamond.

[0042] 5. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that the average cutting efficiency and average cutting life of the diamond tool sintered body are increased by 50% and 60% respectively.

[0043] Implementation Method 3

[0044] 1. A method for preparing a new type of high entropy alloy powder for diamond tools, characterized in that it comprises the following steps:

[0045] (1) According to the requirements of diamond tools for "wettability", "wear resistance" and "high temperature resistance", alloy elements (Fe, Co, Cr, Ni, Cu, W, C) were selected. In order to obtain a stable solid solution high entropy alloy, the range of elements in the dual-phase high entropy alloy was clarified using the traditional phase structure criterion, and the "eutectic surface" of the wear-resistant alloy system was obtained by combining the extrapolation method and phase diagram calculation. A new high entropy alloy system FeCoCrNiCu with a dual-phase structure for diamond tools was initially obtained. 2.0 W 0.2 C 0.5 .

[0046] (2) For the eutectic high entropy alloy system in step (1), a high-throughput casting verification experiment was performed using differential scanning calorimetry (DSC). The purity of the high entropy alloy powder was 99.0-99.5%, and the particle size was 50-80 μm. It was prepared in a suspension melting furnace, protected by high-purity argon gas, and the melting process was repeated 4 times to ensure uniform composition of the cast alloy.

[0047] (3) For the quasi-eutectic high entropy alloy casting FeCoCrNiCu in step (2) 2.0 W 0.2 C 0.5 , further increase the content of Laves phase, adjust the associated elements Ni and Cr of the original phase structure, and thus obtain a new high-temperature eutectic high-entropy alloy system FeCoNi 2.0 Cr 1.2 Cu 1.5 W 0.2 C 0.5 .

[0048] (4) For the high entropy alloy obtained in step (3), its elastic modulus is about 655N / mm 2 .

[0049] (5) For the high entropy alloy obtained in step (3), its relative hardness is: FeCoNi under the conditions of abrasive geometric characteristics, load, sliding speed, etc. 2.0 Cr 1.2 Cu 1.5 W 0.2 C 0.5 The wear rate is 8.74mm 3 / N·m.

[0050] (6) In order to obtain eutectic high entropy alloy powder with excellent particle morphology, the specific gas atomization process is as follows: gas flow rate 0.20m 3 / s, melt flow rate 55kg / min, air pressure 0.55MPa, gas flow rate 60m / s.

[0051] 2. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that the designed eutectic high entropy alloy casting realizes a dual-phase eutectic structure of face-centered cubic (FCC) and hexagonal close-packed (Laves), and the eutectic width is 0.644μm.

[0052] 3. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the performance of the eutectic high entropy alloy casting obtained by the design is better than that of traditional diamond alloy powder; and the comprehensive performance can be stably improved by more than 60% compared with existing products of the same grade, and it can better meet the selection of material structure and mechanical properties in terms of wear resistance, high temperature resistance or actual specific environment.

[0053] 4. A novel eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the eutectic high entropy alloy sintered body designed has a high elastic modulus (=655N / mm 2 ≥650N / mm 2) and low plastic elongation (=1.48%≤1.5%), and has good wettability for diamond.

[0054] 5. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that the average cutting efficiency and average cutting life of the diamond tool sintered body are increased by 50% and 60% respectively.

[0055] Implementation Method 4

[0056] 1. A method for preparing a new type of high entropy alloy powder for diamond tools, characterized in that it comprises the following steps:

[0057] (1) According to the requirements of diamond tools for "wettability", "wear resistance" and "high temperature resistance", alloy elements (Fe, Co, Cr, Ni, Cu, W, C) were selected. In order to obtain a stable solid solution high entropy alloy, the range of elements in the dual-phase high entropy alloy was clarified using the traditional phase structure criterion, and the "eutectic surface" of the wear-resistant alloy system was obtained by combining the extrapolation method and phase diagram calculation. A new high entropy alloy system FeCoCrNiCu with a dual-phase structure for diamond tools was initially obtained. 2.0 W 0.2 C 0.5 .

[0058] (2) For the eutectic high entropy alloy system in step (1), a high-throughput casting verification experiment was performed using differential scanning calorimetry (DSC). The purity of the high entropy alloy powder was 99.0-99.5%, and the particle size was 50-80 μm. It was prepared in a suspension melting furnace, protected by high-purity argon gas, and the melting process was repeated 4 times to ensure uniform composition of the cast alloy.

[0059] (3) For the quasi-eutectic high entropy alloy casting FeCoCrNiCu in step (2) 2.0 W 0.2 C 0.5 , further increase the content of Laves phase, adjust the associated elements Ni and Cr of the original phase structure, and thus obtain a new high-temperature eutectic high-entropy alloy system FeCoNi 2.0 Cr 1.2 Cu 1.5 W 0.2 C 0.77 .

[0060] (4) For the high entropy alloy obtained in step (3), its elastic modulus is about 702N / mm 2 .

[0061] (5) For the high entropy alloy obtained in step (3), its relative hardness is: FeCoNi under the conditions of abrasive geometric characteristics, load, sliding speed, etc. 2.0 Cr 1.2 Cu1.5 W 0.2 C 0.77 The wear rate is 5.96mm 3 / N·m.

[0062] (6) In order to obtain eutectic high entropy alloy powder with excellent particle morphology, the specific gas atomization process is as follows: gas flow rate 0.21m 3 / s, melt flow rate 55kg / min, air pressure 0.60MPa, gas flow rate 60m / s.

[0063] 2. A new type of eutectic high entropy alloy designed according to the method described in claim 1, characterized in that the designed eutectic high entropy alloy casting realizes a dual-phase eutectic structure of face-centered cubic (FCC) and hexagonal close-packed (Laves), and the eutectic width is 0.598μm.

[0064] 3. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the performance of the eutectic high entropy alloy casting obtained by the design is better than that of traditional diamond alloy powder; and the comprehensive performance can be stably improved by more than 60% compared with existing products of the same grade, and it can better meet the selection of material structure and mechanical properties in terms of wear resistance, high temperature resistance or actual specific environment.

[0065] 4. A novel eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the eutectic high entropy alloy sintered body designed has a high elastic modulus (=702N / mm 2 ≥650N / mm 2 ) and low plastic elongation (=1.31%≤1.5%), and has good wettability for diamond.

[0066] 5. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that the average cutting efficiency and average cutting life of the diamond tool sintered body are increased by 50% and 60% respectively.

[0067] Implementation Method 5

[0068] 1. A method for preparing a new type of high entropy alloy powder for diamond tools, characterized in that it comprises the following steps:

[0069] (1) According to the requirements of diamond tools for "wettability", "wear resistance" and "high temperature resistance", alloy elements (Fe, Co, Cr, Ni, Cu, W, C) were selected. In order to obtain a stable solid solution high entropy alloy, the range of elements in the dual-phase high entropy alloy was clarified using the traditional phase structure criterion, and the "eutectic surface" of the wear-resistant alloy system was obtained by combining the extrapolation method and phase diagram calculation. A new high entropy alloy system FeCoCrNiCu with a dual-phase structure for diamond tools was initially obtained.2.0 W 0.2 C 0.5 .

[0070] (2) For the eutectic high entropy alloy system in step (1), a high-throughput casting verification experiment was performed using differential scanning calorimetry (DSC). The purity of the high entropy alloy powder was 99.0-99.5%, and the particle size was 50-80 μm. It was prepared in a suspension melting furnace, protected by high-purity argon gas, and the melting process was repeated 4 times to ensure uniform composition of the cast alloy.

[0071] (3) For the quasi-eutectic high entropy alloy casting FeCoCrNiCu in step (2) 2.0 W 0.2 C 0.5 , further increase the content of FCC phase, adjust the associated elements Ni and Cr of the original phase structure, and thus obtain a new high-temperature eutectic high-entropy alloy system FeCoNi 2.0 Cr 1.2 Cu 1.5 W 0.2 C 0.71 .

[0072] (4) For the high entropy alloy obtained in step (3), its elastic modulus is about 685N / mm 2 .

[0073] (5) For the high entropy alloy obtained in step (3), its relative hardness is: FeCoNi under the conditions of abrasive geometric characteristics, load, sliding speed, etc. 2.0 Cr 1.2 Cu 1.5 W 0.2 C 0.71 The wear rate is 6.65mm 3 / N·m.

[0074] (6) In order to obtain eutectic high entropy alloy powder with excellent particle morphology, the specific gas atomization process is as follows: gas flow rate 0.18m 3 / s, melt flow rate 48kg / min, air pressure 0.60MPa, gas flow rate 60m / s.

[0075] 2. A new type of eutectic high entropy alloy designed according to the method described in claim 1, characterized in that the designed eutectic high entropy alloy casting realizes a dual-phase eutectic structure of face-centered cubic (FCC) and hexagonal close-packed (Laves), and the eutectic width is 0.598μm.

[0076] 3. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the performance of the eutectic high entropy alloy casting obtained by the design is better than that of traditional diamond alloy powder; and the comprehensive performance can be stably improved by more than 60% compared with existing products of the same grade, and it can better meet the selection of material structure and mechanical properties in terms of wear resistance, high temperature resistance or actual specific environment.

[0077] 4. A novel eutectic high entropy alloy designed according to the method of claim 1, characterized in that: the eutectic high entropy alloy sintered body designed has a high elastic modulus (=694N / mm 2 ≥650N / mm 2 ) and low plastic elongation (=1.44%≤1.5%), and has good wettability for diamond.

[0078] 5. A new type of eutectic high entropy alloy designed according to the method of claim 1, characterized in that the average cutting efficiency and average cutting life of the diamond tool sintered body are increased by 50% and 60% respectively.

Claims

1. Preparation of a new type of high entropy alloy powder for diamond tools, characterized in that: The following steps are involved: (1) According to the requirements of diamond tools for "wettability", "wear resistance" and "high temperature resistance", alloy elements (Fe, Co, Cr, Ni, Cu, W, C) are selected. In order to obtain a stable solid solution high entropy alloy, the traditional phase structure criterion is used to clarify the range of elements in the dual-phase high entropy alloy, and the "eutectic surface" of the wear-resistant alloy system is obtained by combining the extrapolation method and phase diagram calculation. A new eutectic high entropy alloy system for high-end diamond tools is initially obtained. (2) For the eutectic high entropy alloy system in step (1), a high-throughput casting verification experiment was performed using differential scanning calorimetry (DSC). The purity of the high entropy alloy powder was 99.0-99.5%, and the particle size was 50-80 μm. It was prepared in a suspension melting furnace, protected by high-purity argon gas, and the melting process was repeated 4 times to ensure uniform composition of the cast alloy. (3) Based on the relationship between the composition and structure of the quasi-eutectic high entropy alloy casting in step (2), the two-phase composition is further optimized to achieve feedback adjustment of the original design method, thereby obtaining a new high-temperature eutectic high entropy alloy system. (4) For the high entropy alloy obtained in step (3), a high elastic modulus eutectic high entropy alloy system is obtained using "elastic modulus" as a screening criterion. (5) Preliminary study of the wear resistance of the new eutectic high entropy alloy under conditions such as relative hardness, geometric characteristics of abrasives, load, and sliding speed, and screen out the optimal wear-resistant eutectic high entropy alloy system in step (4). (6) Systematically explore the gas atomization process to obtain eutectic high-entropy alloy powder with excellent particle morphology.

2. A novel eutectic high entropy alloy designed according to the method of claim 1, characterized in that: The eutectic high entropy alloy casting obtained by the design realizes a dual-phase eutectic structure of face-centered cubic (FCC) and close-packed hexagonal (Laves), and the eutectic width is 0.598-0.725 μm.

3. A novel eutectic high entropy alloy designed according to the method of claim 1, characterized in that: The performance of the eutectic high entropy alloy casting obtained by the design is better than that of traditional diamond alloy powder; and the comprehensive performance can be stably improved by more than 60% compared with existing products of the same grade, which can better meet the selection of material structure and mechanical properties in terms of wear resistance, high temperature resistance or actual specific environment.

4. A novel eutectic high entropy alloy designed according to the method of claim 1, characterized in that: The eutectic high entropy alloy sintered body obtained by the design has a high elastic modulus (≥650N / mm 2 ) and low plastic elongation (≤1.5%), and has good wettability to diamond.

5. A novel eutectic high entropy alloy designed according to the method of claim 1, characterized in that: The average cutting efficiency and average cutting life of diamond tool sintered bodies are increased by 50% and 60% respectively.