CN111745155B

CN111745155B - Low-melting-point cladding alloy powder, preparation method thereof and iron-based diamond matrix

Info

Publication number: CN111745155B
Application number: CN202010662465.9A
Authority: CN
Inventors: 张冠星; 张雷; 刘晓芳; 薛行雁; 董宏伟; 马佳; 张亮
Original assignee: Zhengzhou Research Institute of Mechanical Engineering Co Ltd
Current assignee: Zhengzhou Research Institute of Mechanical Engineering Co Ltd
Priority date: 2020-07-10
Filing date: 2020-07-10
Publication date: 2022-07-12
Anticipated expiration: 2040-07-10
Also published as: CN111745155A

Abstract

The invention relates to the technical field of diamond tool matrix, in particular to low-melting cladding alloy powder, a preparation method thereof and an iron-based diamond matrix. The low-melting cladding alloy powder is of a core-shell structure, a shell layer comprises any one of Sn and Bi, and a core layer comprises FeCuNi prealloy. The preparation method of the low-melting cladding alloy powder comprises the following steps: under the action of a dispersing agent, ball-milling the mixture of Sn powder or Bi powder and FeCuNi prealloying powder, drying and screening. In the low-melting cladding alloy powder, in the sintering process of a matrix, a liquid phase formed by Sn or Bi and Cu on the surface of FeCuNi particles can form a Cu-Sn or Cu-Bi alloy liquid phase, and the Cu-Sn or Cu-Bi alloy liquid phase is rapidly diffused along the surface layer of the FeCuNi particles and permeates into gaps of the FeCuNi particles; improved tissue homogeneity, improved strength, etc.

Description

Low-melting-point cladding alloy powder, preparation method thereof and iron-based diamond matrix

Technical Field

The invention relates to the technical field of diamond tool matrix, in particular to low-melting cladding alloy powder, a preparation method thereof and an iron-based diamond matrix.

Background

The matrix system of the diamond tool can be divided into Co base, Cu base, Fe base, Ni base and the like according to the main components of the matrix metal. The Co-based matrix has good low-temperature bonding property, high temperature resistance, good wettability and lower corrosivity on diamond; good abrasion performance, high bending strength and easy alloying with other elements, but Co is a scarce strategic resource and is expensive. The Cu-based matrix is low in price, high in edge, but low in hardness and strength; the Ni base has good ductility, toughness and oxidation resistance, but the overall performance of the Ni base is poorer than that of the Co base, the price of the material is higher than that of the Fe base, and the overall price ratio is not high. The Fe-based matrix has good wettability and proper mechanical property, small crack tendency and low price, and the substitution of Fe for Co is always the development trend of diamond tools, but the Fe-based matrix diamond tools have the problems of high sintering temperature, narrow controllable process range, easy hot erosion of diamond, weak holding force, easy burning of the matrix and the like in the manufacturing process.

When the traditional iron-based matrix is prepared, Cu powder, Sn powder and Ni powder are added into Fe powder, and then the mixture is sintered. During sintering, Sn begins to melt at a relatively low temperature (231 ℃) to form a liquid phase, and is in contact with Cu in a particle system under the action of pre-sintering pressure and dissolves the Cu to form a continuous Cu-Sn alloy liquid phase. However, due to the poor wettability between the liquid phase of the Cu-Sn alloy and the Fe particles and the uneven distribution of the liquid phase and the Fe particles in the system, most of the liquid phase of the Cu-Sn alloy cannot penetrate into the cracks of the Fe particles to form effective bonding, so that a large number of Fe particles in the system are contacted with each other under the action of sintering pressure and form weak solid-phase sintering. In this system, although a liquid phase is generated, the liquid phase does not effectively wet and bond the solid particles, and the sintering mode causes the structural non-uniformity of the sample, and influences the sintering effect and the tool performance. Therefore, it is an urgent technical problem to develop an iron-based diamond matrix capable of improving the texture uniformity and the bonding strength of a sintered body.

In view of the above, the present invention is particularly proposed.

Disclosure of Invention

The first purpose of the invention is to provide low-melting cladding alloy powder to solve the technical problems of poor uniformity of components and structure and the like in the prior art.

The second purpose of the invention is to provide the low-melting cladding alloy powder, and the preparation method is simple to operate and mild in condition.

The third purpose of the invention is to provide the iron-based diamond matrix, the components and the structure of the iron-based diamond matrix are uniformly distributed, and the generation of component segregation is avoided.

The fourth purpose of the invention is to provide a preparation method of the iron-based diamond matrix, which has no chemical process, does not pollute the environment, can form effective bonding and enables the organization structure to be distributed more uniformly.

The low-melting cladding alloy powder is of a core-shell structure, a shell layer comprises any one of Sn and Bi, and a core layer comprises FeCuNi prealloy.

The core-shell structure is a structure formed by coating a shell layer material on the surface of a core layer material.

When the low-melting cladding alloy powder is used for preparing a matrix, in the sintering process of the matrix, due to the special core-shell structure, a liquid phase formed by Sn or Bi and Cu on the surface of FeCuNi particles can form a Cu-Sn or Cu-Bi alloy liquid phase, and the Cu-Sn or Cu-Bi alloy liquid phase rapidly diffuses along the surface layer of the FeCuNi particles and permeates into gaps of the FeCuNi particles. Finally, the Cu-Sn or Cu-Bi alloy can form a continuous network structure, FeCuNi particles are wrapped and bonded, the skeleton phase FeCuNi is in a granular shape and is tightly bonded in the network, and the composition and the organization structure of the bonding agent are distributed more uniformly by the formation of the structure, so that the composition segregation is avoided. And when the tyre body is prepared, the tyre body has the same existence with other elements in the tyre body, has better affinity according to the similar compatible principle, and is easy to combine with each other.

In a specific embodiment of the invention, the mass ratio of the shell layer to the nuclear layer is 1: 15 (5: 15), preferably 1: 8 (10), and more preferably 1: 9.

In various embodiments, the shell and nuclear shells can be at a mass ratio of 1: 5, 1: 6, 1: 7, 1: 8, 1: 9, 1: 10, 1: 11, 1: 12, 1: 13, 1: 14, 1: 15, etc.

In a specific embodiment of the present invention, the low melting point cladding alloy powder has a particle size of 45 to 150 μm.

In a specific embodiment of the present invention, the fecunin prealloy comprises, by weight, Fe 64% to 65%, Cu 28% to 29%, and Ni 6.5% to 7.5%, and preferably comprises Fe 64.5%, Cu 28.5%, and Ni 7%.

The invention also provides a preparation method of the low-melting-point cladding alloy powder, which comprises the following steps:

under the action of a dispersing agent, ball milling treatment is carried out on a mixture of Sn powder or Bi powder and FeCuNi prealloying powder, and then drying treatment is carried out.

In a specific embodiment of the present invention, after the drying treatment, screening is further included. And screening according to the actually required granularity to obtain the low-melting cladding alloy powder with the core-shell structure with the required granularity.

Wherein the purity of Sn powder and Bi powder is more than or equal to 99.9 percent.

In a specific embodiment of the present invention, the average particle diameter of the Sn powder or Bi powder is 45 μm or less; the average particle size of the FeCuNi prealloying powder is 75-150 mu m.

The mass ratio of the Sn powder or the Bi powder to the FeCuNi prealloyed powder is 1: (5-15), preferably 1: (8-10), and more preferably 1: 9.

In a specific embodiment of the present invention, the ball milling conditions include: the rotation speed of ball milling is 300-500 r/min, the ball milling time is 20-40 h, and the ball-to-material ratio of ball milling is (18-22): 1. Preferably, the ball milling conditions include: the rotation speed of ball milling is 400r/min, the ball milling time is 20-40 h, and the ball-to-material ratio of ball milling is 20: 1. Furthermore, the medium for ball milling is agate balls.

In practice, the ball milling treatment may be carried out in an agate jar, such as an agate jar.

In a particular embodiment of the invention, the drying is carried out under vacuum. Further, the drying temperature is 100-120 ℃, and the drying time is more than or equal to 2 hours. Specifically, the vacuum degree under the vacuum condition is-0.1 MPa or the vacuum degree is higher than-0.1 MPa. By using vacuum conditions, oxidation of the powder is prevented.

In a particular embodiment of the invention, the dispersant comprises ethanol and/or acetone. By adding the dispersing agent, the sphericity of the prepared low-melting-point cladding alloy powder with the core-shell structure is improved, and powder adhesion is avoided.

In a specific embodiment of the present invention, the amount of the dispersant added is 3% to 5% by mass of the mixture.

The addition amount of the dispersant is within the above range, which can avoid the adhesion of the powder, ensure the uniformity of the powder dispersion, and further improve the sphericity of the low-melting-point clad alloy powder.

The invention also provides an iron-based diamond matrix which is mainly prepared from the following components in percentage by weight:

35-45% of Fe, 15-20% of Cu, 5-10% of Sn, 3-5% of Ni and 25-35% of low-melting cladding alloy powder;

wherein the low-melting-point cladding alloy powder is any one of the low-melting-point cladding alloy powders.

As in the different embodiments, the amount of component Fe may be 35%, 36%, 37%, 38%, 39%, 40%, 41%, 42%, 43%, 44%, 45%, etc. in the iron-based diamond matrix; the amount of component Cu may be 15%, 16%, 17%, 18%, 19%, 20%, etc.; the amount of component Sn may be 5%, 6%, 7%, 8%, 9%, 10%, etc.; component Ni can be used in amounts of 3%, 3.5%, 4%, 4.5%, 5%, etc.; the amount of the constituent low-melting clad alloy powder may be 25%, 26%, 27%, 28%, 29%, 30%, 31%, 32%, 33%, 34%, 35%, etc.

In a preferred embodiment of the invention, the iron-based diamond matrix is prepared by the following components in percentage by weight:

38-43% of Fe, 15-19% of Cu, 7-9% of Sn, 3-4% of Ni and 28-32% of low-melting cladding alloy powder.

In a further preferred embodiment of the invention, the iron-based diamond matrix is prepared from the following components in percentage by weight:

40.7% of Fe, 17.5% of Cu, 8% of Sn, 3.8% of Ni and 30% of low-melting cladding alloy powder.

The preparation method of the iron-based diamond matrix comprises the following steps:

fe. And uniformly mixing the simple substance powder of Cu, Sn and Ni and the low-melting cladding alloy powder in proportion, and performing hot-pressing sintering.

Specifically, the uniformly mixed materials can be placed in a mold, and then hot-pressed and sintered. The mould can be selected according to the shape requirement of an actual tyre body.

In a specific embodiment of the invention, the mixing is carried out by a vacuum mixer, and the mixing time is more than or equal to 2 hours. Further, the vacuum mixer may adopt a V-shaped vacuum mixer, but is not limited thereto.

In a specific embodiment of the present invention, the hot press sintering is performed under vacuum conditions. Further, the vacuum degree under the vacuum condition is-0.1 MPa or the vacuum degree is higher than-0.1 MPa. By using vacuum conditions, oxidation is prevented.

In a specific embodiment of the invention, the temperature of the hot-pressing sintering is 700-750 ℃, the pressure of the hot-pressing sintering is 18-22 MPa, and the heat preservation and pressure maintaining time of the hot-pressing sintering is 5-10 min; preferably, the temperature of the hot-pressing sintering is 750 ℃, the pressure of the hot-pressing sintering is 20MPa, and the heat preservation and pressure maintaining time of the hot-pressing sintering is 5-10 min.

Compared with the prior art, the invention has the beneficial effects that:

(1) the invention adopts specific low-melting cladding alloy powder for preparing the matrix, overcomes the problems that the majority of Cu-Sn liquid phase formed by adopting Fe, Cu, Sn and Ni simple substance powder in the traditional matrix preparation cannot penetrate into the cracks of Fe particles to effectively bond the Fe particles, so that the structural nonuniformity of a sample and the poor tool performance are caused;

(2) in the sintering process of the matrix, the low-melting cladding alloy powder has the advantages that due to the special core-shell structure, a liquid phase formed by Sn or Bi and Cu on the surface of FeCuNi particles can form a Cu-Sn or Cu-Bi alloy liquid phase, and the Cu-Sn or Cu-Bi alloy liquid phase rapidly diffuses along the surface layer of the FeCuNi particles and permeates into gaps of the FeCuNi particles; a continuous network structure is formed, FeCuNi particles are wrapped and bonded, and skeleton phase FeCuNi is tightly bonded in the network in a particle shape, so that the distribution of components and an organization structure is more uniform, and the occurrence of component segregation is avoided;

(3) the preparation method of the low-melting-point cladding alloy powder belongs to a physical preparation method, has no pollution risk of a chemical process to the environment, and has good cladding effect of a shell to a core and nearly spherical powder appearance.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a reaction diagram of a sintering process; wherein, (a) is a reaction schematic diagram of the sintering process of the simple substance powder, and (b) is a reaction schematic diagram of the sintering process of the low-melting cladding alloy powder;

FIG. 2 is a scanning element distribution diagram of the low melting coating alloy powder prepared in example 1 of the present invention;

FIG. 3 is a scanning element distribution diagram of the low melting coating alloy powder prepared in example 2 of the present invention;

FIG. 4 is a microstructure map of different carcasses; wherein (a) is the cobalt-based matrix of comparative example 1, (b) is the iron-based diamond matrix of example 3, and (c) is the iron-based diamond matrix of example 4.

Detailed Description

The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings and the detailed description, but those skilled in the art will understand that the following described embodiments are some, not all, of the embodiments of the present invention, and are only used for illustrating the present invention, and should not be construed as limiting the scope of the present invention. All other embodiments, which can be obtained by a person skilled in the art without making any creative effort based on the embodiments in the present invention, belong to the protection scope of the present invention. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

Example 1

This example provides a low-melting cladding alloy powder, which is a core-shell structure with a shell layer of Sn and a core layer of fecunin pre-alloy. The mass ratio of the shell layer to the nuclear layer is 1: 9. The low-melting coating alloy powder with the shell layer of Sn and the core layer of FeCuNi pre-alloy is referred to as FeCuNi-Sn low-melting coating alloy powder for short.

The preparation method of the fecunin-Sn low-melting cladding alloy powder of the embodiment includes the following steps:

(1) and mixing Sn powder (the purity is more than or equal to 99.9%) with the average particle size of less than 45 mu m and FeCuNi prealloy with the average particle size of 75-150 mu m according to the mass ratio of 1: 9, filling the mixture into an agate tank, wherein agate balls are arranged in the agate tank, the ball-to-material ratio is 20: 1, adding absolute ethyl alcohol (the addition amount of the absolute ethyl alcohol is 3% of the total mass of the Sn powder and the prealloy), and starting ball milling at the rotation speed of 400r/min for 20 h.

(2) And (2) drying the ball-milled material in the step (1) in a vacuum drying oven, wherein the vacuum degree reaches-0.1 MPa or higher, the drying temperature is 120 ℃, and the drying and heat preservation time is 2 hours.

(3) And (3) placing the powder obtained in the step (2) in a standard rotary vibration sieve for particle size screening to obtain low-melting coating alloy powder FeCuNi-Sn with a core-shell structure and the required particle size of 50-150 mu m.

Wherein the FeCuNi prealloy comprises the following components in percentage by weight: fe 64.5%, Cu28.5% and Ni 7%.

Example 2

This example provides a low-melting cladding alloy powder with a core-shell structure, a shell layer of Bi, and a core layer of fecunin pre-alloy. The mass ratio of the shell layer to the nuclear layer is 1: 9. The low-melting coating alloy powder with the shell layer of Bi and the core layer of FeCuNi pre-alloy is referred to as FeCuNi-Bi low-melting coating alloy powder for short.

The preparation method of FeCuNi-Bi low-melting cladding alloy powder comprises the following steps:

(1) bi powder (the purity is more than or equal to 99.9%) with the average particle size of less than 45 mu m and FeCuNi prealloy with the average particle size of 75-150 mu m are mixed according to the mass ratio of 1: 9 and are loaded into an agate tank, agate balls are arranged in the agate tank, the ball-material ratio is 20: 1, absolute ethyl alcohol (the addition amount of the absolute ethyl alcohol is 3% of the total mass of the Bi powder and the prealloy) is added, ball milling is started, the rotating speed is 400r/min, and the ball milling time is 20 h.

(3) And (3) placing the powder obtained in the step (2) in a standard rotary vibration sieve for particle size screening to obtain low-melting coating alloy powder FeCuNi-Bi with the required particle size of 50-150 mu m and a core-shell structure.

Wherein the FeCuNi prealloy comprises the following components in percentage by weight: fe 64.5%, Cu 28.5% and Ni 7%.

Example 3

This example provides a diamond matrix, prepared from the following components in weight percent:

40.7% of Fe, 17.5% of Cu, 8% of Sn, 3.8% of Ni and 30% of low-melting cladding alloy powder; wherein the low-melting-point coating alloy powder is FeCuNi-Sn which is the low-melting-point coating alloy powder prepared in the embodiment 1.

The preparation method of the diamond matrix comprises the following steps:

(1) weighing Fe simple substance powder, Cu simple substance powder, Sn simple substance powder, Ni simple substance powder and FeCuNi-Sn powder according to the mass ratio of 40.7%, 17.5%, 8%, 3.8% and 30%, and then mixing for 2 hours in a vacuum mixer;

(2) putting the mixed material obtained in the step (1) into a preset die, and sintering in a vacuum hot-pressing sintering mode to obtain an iron-based diamond matrix; the vacuum hot-pressing sintering conditions comprise: the vacuum degree reaches-0.1 MPa or higher, the hot-pressing sintering temperature is 750 ℃, the hot-pressing sintering pressure is 20MPa, and the heat preservation and pressure maintaining time of the hot-pressing sintering is 5 min.

Wherein the mold is selected according to the shape of the actual target carcass.

Example 4

40.7% of Fe, 17.5% of Cu, 8% of Sn, 3.8% of Ni and 30% of low-melting cladding alloy powder; wherein the low-melting-point cladding alloy powder is FeCuNi-Bi prepared in example 2.

The preparation method of the diamond matrix comprises the following steps:

(1) weighing Fe simple substance powder, Cu simple substance powder, Sn simple substance powder, Ni simple substance powder and FeCuNi-Bi powder according to the mass ratio of 40.7%, 17.5%, 8%, 3.8% and 30%, and then mixing for 2 hours in a vacuum mixer;

Comparative example 1

Comparative example 1 is a cobalt-based carcass, made of the following components in mass percent:

fe 36%, Cu 26%, Sn 8% and Co 30%.

The preparation method of the cobalt-based matrix comprises the following steps:

(1) weighing Fe simple substance powder, Cu simple substance powder, Sn simple substance powder and Co simple substance powder according to the mass ratio of 36%, 26%, 8% and 30%, and then mixing for 2h in a vacuum mixer;

(2) putting the mixed material obtained in the step (1) into a preset mold, and sintering in a vacuum hot-pressing sintering mode to obtain a cobalt-based tire body; the vacuum hot-pressing sintering conditions comprise: the vacuum degree reaches-0.1 MPa or higher, the hot-pressing sintering temperature is 750 ℃, the hot-pressing sintering pressure is 20MPa, and the heat preservation and pressure maintaining time of the hot-pressing sintering is 5 min.

Experimental example 1

To illustrate the difference between the low melting coating alloy powder of the present invention and the sintering process of the existing elemental powder, as shown in fig. 1, (a) is a reaction diagram of the sintering process of the elemental powder, and (b) is a reaction diagram of the sintering process of the low melting coating alloy powder. As can be seen from the figure, taking the low-melting-point cladding alloy powder fecunin-Sn of the present invention as an example, in the sintering process of the matrix, due to the special core-shell structure, the liquid phase formed by Sn can form a Cu-Sn alloy liquid phase with Cu on the surface of fecunin particles, and rapidly diffuse along the surface layer of fecunin particles to penetrate into the gaps of fecunin particles; a continuous network structure is formed, FeCuNi particles are wrapped and bonded, and skeleton phase FeCuNi is in a particle shape and is tightly bonded in the network, so that the distribution of components and an organization structure is more uniform, and the occurrence of component segregation is avoided.

Experimental example 2

To further verify the core-shell structure of the low melting coating alloy powder of the present invention, the low melting coating alloy powder fecunin-Sn and the low melting coating alloy powder fecunin-Bi prepared in examples 1 and 2 were subjected to scanning elemental analysis, as shown in fig. 2 and 3, respectively. As can be seen from the figure, Sn element and Bi element coat the surface of FeCuNi alloy particles.

Experimental example 3

To illustrate the performance of the iron-based diamond matrix of the present invention, the matrix prepared in examples 3 and 4 was compared to the cobalt-based matrix of comparative example 1 and the results of the performance tests are shown in table 1.

Table 1 results of performance testing of different carcasses

As can be seen from Table 1, the iron-based diamond matrix of the present invention has performance comparable to that of a conventional cobalt-based matrix, and does not contain cobalt. FIG. 4 is a microstructure map of different carcasses; wherein (a) is the cobalt-based matrix of comparative example 1, (b) is the iron-based diamond matrix of example 3, and (c) is the iron-based diamond matrix of example 4. As can be seen from the figure, the carcass of the invention has more uniform overall structure and improved density.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. The iron-based diamond matrix is characterized by being mainly prepared from the following components in percentage by weight:

35-45% of Fe, 15-20% of Cu, 5-10% of Sn, 3-5% of Ni and 25-35% of low-melting cladding alloy powder; the low-melting cladding alloy powder is of a core-shell structure, a shell layer comprises any one of Sn and Bi, and a core layer comprises FeCuNi prealloy; the mass ratio of the shell layer to the nuclear layer is 1: 5-15.

2. The iron-based diamond matrix of claim 1, wherein the shell layer and the core layer are present at a mass ratio of 1: 8 to 10.

3. The iron-based diamond matrix of claim 1, wherein the shell layer and the core layer are present at a mass ratio of 1: 9.

4. The iron-based diamond matrix according to any one of claims 1 to 3, wherein the low-melting cladding alloy powder has a particle size of 45 to 150 μm.

5. The iron-based diamond matrix of claim 1, wherein the FeCuNi prealloy comprises, in weight percent, Fe 64-65%, Cu 28-29%, and Ni6.5-7.5%.

6. The iron-based diamond matrix according to claim 1, wherein the method of preparing the low-melting cladding alloy powder comprises the steps of:

under the action of a dispersing agent, ball milling treatment is carried out on a mixture of Sn powder and FeCuNi prealloying powder or Bi powder and FeCuNi prealloying powder, and then drying treatment is carried out.

7. The iron-based diamond matrix according to claim 6, wherein screening is performed after the drying process.

8. The iron-based diamond matrix according to claim 6, wherein the average grain size of the Sn or Bi powder is 45 μm or less; the average particle size of the FeCuNi prealloying powder is 75-150 mu m.

9. The iron-based diamond matrix of claim 6, wherein the ball milling conditions include: the rotation speed of ball milling is 300-500 r/min, the ball milling time is 20-40 h, and the ball-to-material ratio of ball milling is (18-22): 1.

10. The iron-based diamond matrix according to claim 9, wherein the rotation speed of the ball milling is 400r/min, the ball milling time is 20-40 h, and the ball-to-material ratio of the ball milling is 20: 1.

11. The iron-based diamond matrix according to claim 6, wherein the drying process is performed under vacuum conditions;

the drying temperature is 100-120 ℃, and the drying time is more than or equal to 2 h.

12. The iron-based diamond matrix of claim 11, wherein the vacuum condition is at a vacuum level of-0.1 MPa or at a vacuum level greater than-0.1 MPa.

13. The iron-based diamond matrix of claim 6, wherein the dispersant comprises ethanol and/or acetone.

14. The iron-based diamond matrix according to claim 13, wherein the dispersant is added in an amount of 3% to 5% by mass of the mixture.

15. The method for preparing an iron-based diamond matrix according to any one of claims 1 to 14, wherein the elemental powders of Fe, Cu, Sn and Ni and the low-melting coating alloy powder are uniformly mixed in proportion and subjected to hot-pressing sintering.

16. The method of making an iron-based diamond matrix according to claim 15, wherein the hot press sintering is performed under vacuum conditions.

17. The method of making an iron-based diamond matrix according to claim 16, wherein the vacuum condition is at a vacuum level of-0.1 MPa or at a vacuum level higher than-0.1 MPa.

18. The method for preparing the iron-based diamond matrix according to claim 15, wherein the temperature of the hot-pressing sintering is 700-750 ℃, the pressure of the hot-pressing sintering is 18-22 MPa, and the holding time and pressure maintaining time of the hot-pressing sintering are 5-10 min.