CN111545759B

CN111545759B - Drill bit matrix powder, drill bit matrix material, preparation method and application of drill bit matrix material, and drill bit matrix

Info

Publication number: CN111545759B
Application number: CN202010411225.1A
Authority: CN
Inventors: 刘辛; 谭冲; 胡杰
Original assignee: Institute of New Materials of Guangdong Academy of Sciences
Current assignee: Institute of New Materials of Guangdong Academy of Sciences
Priority date: 2020-05-15
Filing date: 2020-05-15
Publication date: 2022-03-29
Anticipated expiration: 2040-05-15
Also published as: CN111545759A

Abstract

The invention discloses drill bit matrix powder, a drill bit matrix material, a preparation method and application of the drill bit matrix material and a drill bit matrix, and belongs to the technical field of additive manufacturing. The drill bit matrix powder comprises copper alloy powder and spherical nickel/nickel-copper cladding casting tungsten carbide composite powder with a core-shell structure, can realize uniform distribution of a hard phase in a matrix, improves the bonding force of the hard phase and a bonding phase, forms a good interface layer, and has higher hardness than a material prepared by a traditional method. The drill bit matrix material is mainly obtained by selective laser melting and forming of the drill bit matrix powder, so that the prepared drill bit matrix material has the advantages of high density and hardness, uniform tissue, no defects of holes, microcracks and the like, is particularly suitable for drilling of medium-hard stratums, and solves the problems of complicated preparation means, long period, high production, incapability of forming complex structures and the like in the traditional method. The composite material is used for preparing a drill bit matrix, and can greatly improve the comprehensive mechanical property of the drill bit matrix.

Description

Drill bit matrix powder, drill bit matrix material, preparation method and application of drill bit matrix material, and drill bit matrix

Technical Field

The invention relates to the technical field of additive manufacturing, in particular to drill bit matrix powder, a drill bit matrix material, a preparation method and application of the drill bit matrix material and a drill bit matrix.

Background

Matrix drill bits are increasingly used in oil and gas drilling. A conventional Polycrystalline Diamond Compact (PDC) drill bit includes a PDC cutter and a casing, and the PDC cutter is welded to a surface of the casing. The drill bit matrix is used for embedding diamond or fixing PDC and is firmly connected with the drill bit steel body, which is the key for ensuring the quality of the drill bit and is of great importance to the overall drilling efficiency, the service life, the drilling period and the cost of the drill bit. The problems of the falling of the tire body, the breaking of the blade, the core grinding, the cracking and the like seriously affect the drilling speed, increase the drilling cost and cause great economic loss. Therefore, it is very important to develop a high-performance matrix material, and it is very important to manufacture a high-quality matrix drill bit.

At present, PDC drill bit matrix is mainly manufactured by a non-pressure impregnation and hot-pressing sintering method. The non-pressure impregnation process is characterized in that framework powder formed by mixing cast tungsten carbide powder and nickel powder is placed in a graphite die, a certain amount of bonding metal is placed on the framework powder according to powder pores in proportion for impregnation, the bonding metal is melted and permeates into pores of the framework powder to form a drill bit matrix, the framework powder, a drill bit steel body and the bonding metal are integrated, and the problems of poor mixing uniformity of the matrix powder, uncontrollable content of the bonding metal and the like exist. The other method is hot-pressing sintering, but is limited by a die, powder fluidity and the like, so that the requirement of the drill bit matrix on the complex shape forming is difficult to meet. In addition, the two methods have long manufacturing period and high cost, and the welding part becomes a weak link of the drill bit, so that the requirements of energy reduction, environmental protection and drilling cost reduction are difficult to realize.

The additive manufacturing not only can effectively form high-performance parts made of various materials, but also can form precise parts with complex structures. In order to obtain a high-performance diamond bit, the advantages of additive manufacturing are fully exerted, and various diamond bit matrix bodies with complex structures are formed, so that the diamond bit with reasonable design and complex structure is realized.

The performance of the drill bit matrix prepared by 3D printing at present can not meet the requirements of actual complex working environments. The drill bit matrix material manufactured by the additive still has the problems of high porosity, cracks caused by thermal stress and the like.

In view of this, the invention is particularly proposed.

Disclosure of Invention

One of the objects of the present invention includes providing a bit matrix powder which can achieve uniform distribution of a hard phase in a matrix and improve the binding force of the hard phase and a binder phase, forming a good interface layer, and having a hardness higher than that of a material prepared by a conventional method.

The second purpose of the invention is to provide a drill bit matrix material which is prepared from the drill bit matrix powder and has the characteristics of the drill bit matrix powder.

The third purpose of the invention is to provide the preparation method of the drill bit matrix material, which is simple and easy to operate, can ensure that the prepared drill bit matrix material has higher density and hardness, uniform tissue and no defects of holes, microcracks and the like, is particularly suitable for drilling medium-hard stratums, and simultaneously solves the problems of complicated preparation means, long period, high production, incapability of forming complex structures and the like in the traditional method.

The fourth object of the present invention consists in providing the use of the above-mentioned drill bit matrix material, for example for the preparation of drill bit matrices.

The fifth objective of the present invention includes providing a drill bit matrix with better overall mechanical properties.

The application is realized as follows:

in a first aspect, the present application provides a drill bit matrix powder comprising a copper alloy powder and a spherical nickel clad cast tungsten carbide composite powder having a core-shell structure or a spherical nickel copper clad cast tungsten carbide composite powder having a core-shell structure.

In an alternative embodiment, the bit matrix powder comprises 30-85% nickel-clad cast tungsten carbide composite powder or nickel-copper-clad cast tungsten carbide composite powder and 15-70% copper alloy powder by mass percent.

In an alternative embodiment, the nickel clad cast tungsten carbide composite powder or nickel copper clad cast tungsten carbide composite powder has a particle size of 15 to 53 μm.

In an optional embodiment, the nickel-coated cast tungsten carbide composite powder or the nickel-copper-coated cast tungsten carbide composite powder contains 2 to 15 mass percent of nickel and 5 to 10 mass percent of copper.

In an alternative embodiment, the nickel-clad cast tungsten carbide composite powder or the nickel-copper-clad cast tungsten carbide composite powder is prepared by an electroless plating method.

In an alternative embodiment, the cast tungsten carbide in the nickel-clad cast tungsten carbide composite powder or the nickel-copper-clad cast tungsten carbide composite powder is a spherical powder.

In an alternative embodiment, the powder of cast tungsten carbide has WC and W₂Eutectic structure of C.

In an alternative embodiment, the powder of cast tungsten carbide has a particle size of 15-45 μm.

In an alternative embodiment, the total carbon content of the cast tungsten carbide powder is 3.7-4.2% by mass.

In an alternative embodiment, the powder of cast tungsten carbide has a microhardness of 2600-_0.1。

In an alternative embodiment, the copper alloy powder is a spherical powder with a particle size of 325-500 mesh.

In an alternative embodiment, the copper alloy comprises a Cu-Ni alloy or a Cu-Sn alloy.

In an alternative embodiment, the copper alloy is a Cu-Ni alloy containing, in mass percent, 50-85% Cu and 15-50% Ni.

In an alternative embodiment, the copper alloy is a Cu-Sn alloy, which contains 50-85% Cu and 15-50% Sn, in mass percent.

In an alternative embodiment, the copper alloy powder is prepared by means of gas atomization.

In a second aspect, the present application provides a drill bit matrix material, which is mainly formed by selective laser melting and forming of the drill bit matrix powder.

In an alternative embodiment, the density of the drill bit matrix material is 95.3-97.5%.

In an alternative embodiment, the hardness of the bit matrix material is 40.23-51.74 HRC.

In a third aspect, the present application provides a method for preparing the drill bit matrix material, comprising the following steps: and carrying out selective laser melting forming on the drill bit matrix powder.

In an alternative embodiment, the copper alloy powder and the spherical nickel-coated cast tungsten carbide composite powder or nickel-copper-coated cast tungsten carbide composite powder with the shell-core structure are mixed for 2 to 4 hours and then subjected to selective laser melting forming.

In an alternative embodiment, the mixing is performed in a blender.

In an alternative embodiment, the substrate used for selective laser fusion forming comprises a stainless steel substrate or TC4 substrate.

In an alternative embodiment, the working atmosphere for selective laser fusion forming comprises at least one of argon and nitrogen.

In an alternative embodiment, the included angle between the layers during selective laser fusion forming is 30-75 °.

In an alternative embodiment, the pre-heating temperature of the substrate during the selective laser fusion forming process is 80-150 ℃.

In an alternative embodiment, the scan pitch during the selective laser fusion forming process is 0.1-0.2 mm.

In an alternative embodiment, the thickness of the laydown powder during the selective laser fusion forming process is 30-40 μm.

In an alternative embodiment, the scan rate during the selective laser melt shaping process is 160-.

In an alternative embodiment, the laser power during the selective laser melting forming process is 60-200W.

In an alternative embodiment, the spot diameter during selective laser fusion forming is 40-80 μm.

In a fourth aspect, the present application provides the use of a bit matrix material as described above, for example, for making a bit matrix, and further for making a PDC bit matrix for oil and gas exploration.

In a fifth aspect, the present application provides a drill bit matrix, wherein the raw material for preparing the drill bit matrix comprises the drill bit matrix material as described above.

The beneficial effect of this application includes:

by adopting spherical nickel-coated cast tungsten carbide powder or spherical nickel-copper-coated cast tungsten carbide composite powder with a core-shell structure as one of raw materials of the drill bit matrix powder, the drill bit matrix material prepared from the drill bit matrix powder can realize uniform distribution of a hard phase in a matrix in the drill bit matrix, the bonding force of the hard phase and a bonding phase is improved, a good interface layer is formed, and the hardness of the interface layer is higher than that of the material prepared by a traditional method.

Through selective laser melting and forming of the drill bit matrix powder, the prepared drill bit matrix material has the advantages of high density and hardness, uniform structure, no defects of holes, microcracks and the like, is particularly suitable for drilling of medium-hard stratums, and solves the problems of complex preparation means, long period, high production, incapability of forming complex structures and the like of the traditional method. The composite material is used for preparing a drill bit matrix, and can greatly improve the comprehensive mechanical property of the drill bit matrix.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present invention and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained according to the drawings without inventive efforts.

FIG. 1 is a metallographic structure of a drill bit matrix material provided in example 1 of the present application;

FIG. 2 is an electron microscope topography of nickel coated cast tungsten carbide powder in a drill bit matrix material provided in example 1 of the present application;

fig. 3 is an XRD pattern of the drill bit matrix material provided in example 1 of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. 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.

The features and properties of the present invention are described in further detail below with reference to examples.

The application provides drill bit matrix powder which mainly comprises copper alloy powder and spherical nickel-coated cast tungsten carbide composite powder with a core-shell structure or spherical nickel-copper-coated cast tungsten carbide composite powder with a core-shell structure.

The inventors have found that the powders currently used to prepare drill bit casings are not suitable for use in additive manufacturing processes. In the existing formula of the drill bit matrix powder, raw material powder is mainly obtained by mixing non-spherical cast tungsten carbide powder, nickel powder and the like, and fibers, oxides and the like are added to improve the performance of the drill bit matrix material, however, the fibers, the oxides and the like often reduce the quality of a formed drill bit matrix in the additive manufacturing process due to higher laser reflectivity, so that the problems of cracks, holes and the like are caused.

According to the method, the spherical nickel-coated cast tungsten carbide material with the core-shell structure or the spherical nickel-copper-coated cast tungsten carbide composite powder with the core-shell structure is used as one of raw materials of the drill bit matrix powder, so that the use of substances such as fibers and oxides can be avoided, the uniform distribution of a hard phase in a matrix of the drill bit matrix material prepared from the drill bit matrix material can be realized, the bonding force between the hard phase and a bonding phase can be improved, a good interface layer is formed, and the hardness of the interface layer is higher than that of the material prepared by the traditional method.

In an alternative embodiment, the bit matrix powder comprises 30-85% nickel-clad cast tungsten carbide composite powder or nickel-copper-clad cast tungsten carbide composite powder and 15-70% copper alloy powder by mass percent. For example, the alloy powder may contain 30% of nickel-coated cast tungsten carbide composite powder or nickel-copper-coated cast tungsten carbide composite powder and 70% of copper alloy powder, 50% of nickel-coated cast tungsten carbide composite powder or nickel-copper-coated cast tungsten carbide composite powder and 50% of copper alloy powder, 60% of nickel-coated cast tungsten carbide composite powder or nickel-copper-coated cast tungsten carbide composite powder and 40% of copper alloy powder, 70% of nickel-coated cast tungsten carbide composite powder or nickel-copper-coated cast tungsten carbide composite powder and 30% of copper alloy powder, 85% of nickel-coated cast tungsten carbide composite powder or nickel-copper-coated cast tungsten carbide composite powder and 15% of copper alloy powder, or the like.

The nickel-coated cast tungsten carbide or nickel-copper-coated cast tungsten carbide and the copper alloy are in powder form so as to meet the requirement of printing by overlapping layer by layer in a powder laying mode in the selective laser melting process.

In alternative embodiments, the nickel clad cast tungsten carbide composite powder or nickel copper clad cast tungsten carbide composite powder may have a particle size of 15-53 μm, such as 15 μm, 20 μm, 35 μm, 40 μm, 45 μm, 50 μm, 53 μm, or the like.

In an alternative embodiment, the nickel-coated cast tungsten carbide composite powder or nickel-copper-coated cast tungsten carbide composite powder has a nickel content of 2-15% by mass, such as 2%, 5%, 8%, 10%, 12%, 15%, or the like. The composite powder with the nickel content range has high sphericity and proper thickness of the coating layer, and is favorable for forming good metallurgical bonding between the cast tungsten carbide and the nickel substrate in the additive manufacturing process. The copper may be present in an amount of 5-10% by weight, such as 5%, 6%, 7%, 8%, 9% or 10%.

In an alternative embodiment, the nickel clad cast tungsten carbide composite powder or nickel copper clad cast tungsten carbide composite powder may be prepared, for example, by an electroless plating method. The electroless plating method can be referred to the related prior art and is not described herein. The nickel-coated cast tungsten carbide composite powder prepared by chemical plating has the advantages of uniform powder coating, simple process and the like.

In an alternative embodiment, the cast tungsten carbide in the nickel-clad cast tungsten carbide composite powder or the nickel-copper-clad cast tungsten carbide composite powder is a spherical powder. Wherein the powder of cast tungsten carbide has a high content of WC and W₂The higher the content of the eutectic structure of the C is, the higher the microhardness is, and the wear resistance of the material can be improved.

In alternative embodiments, the particle size of the cast tungsten carbide powder may be 15-45 μm, such as 15 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, or 45 μm, and the like.

In an alternative embodiment, the total carbon content of the cast tungsten carbide powder is 3.7-4.2%, preferably 3.92%, in mass percent. The cast tungsten carbide powder with carbon content has less free carbon content and higher eutectic structure content, and is beneficial to improving the comprehensive mechanical property of the material.

In an alternative embodiment, the powder of cast tungsten carbide has a microhardness of 2600-_0.1For example 2600HV_0.1、3000HV_0.1Or 3100HV_0.1And the like.

In an alternative embodiment, the copper alloy powder is a spherical powder with a particle size of 325-500 mesh (e.g., 325 mesh, 400 mesh, 450 mesh, 500 mesh, etc.).

In certain alternative embodiments, the copper alloy is a Cu-Ni alloy comprising, in mass percent, 50-85% Cu and 15-50% Ni, preferably 75% Cu and 25% Ni.

In certain alternative embodiments, the copper alloy is a Cu-Sn alloy, which comprises, in mass percent, 50-85% Cu and 15-50% Sn, preferably 75% Cu and 25% Sn.

In an alternative embodiment, the copper alloy powder may be prepared by gas atomization. The related prior art can be referred to for the aerosolization process, which is not described herein. Compared with the copper alloy powder prepared by water atomization, the copper alloy powder prepared by gas atomization has lower oxygen content and higher sphericity, and is favorable for obtaining a drill bit matrix material with high density.

In addition, the application also provides a drill bit matrix material which is mainly formed by selective laser melting and forming of the drill bit matrix powder.

In an alternative embodiment, the bit matrix material provided herein has a density of 95.3 to 97.5% and a hardness of 40.23 to 51.74 HRC.

In addition, the application also provides a preparation method of the drill bit matrix material, which comprises the following steps: and carrying out selective laser melting forming on the drill bit matrix powder.

In an alternative embodiment, the copper alloy and the spherical nickel-coated cast tungsten carbide composite powder with the shell-core structure are mixed for 2 to 4 hours, for example, 2 hours and then subjected to selective laser melting forming. The mixing may, by reference, be carried out in a mixer.

In an alternative embodiment, the substrate for selective laser melting formation may be, for example, a stainless steel substrate, and further, a TC4 substrate or the like may be used.

In an alternative embodiment, the working atmosphere for selective laser melting may include argon, for example, and may be formed from nitrogen, among others.

In an alternative embodiment, the included angle between the layers during selective laser fusion forming is 30-75 °, preferably 67 °.

In an alternative embodiment, the preheating temperature of the substrate during the selective laser melting forming process is 80-150 ℃, such as 80 ℃, 90 ℃, 100 ℃, 110 ℃, 120 ℃, 130 ℃, 140 ℃ or 150 ℃. Within this preheating temperature range, microcracks caused by thermal stress can be effectively reduced.

In alternative embodiments, the scan pitch during selective laser melt forming is 0.1-0.2mm, such as 0.1mm, 0.15mm, or 0.2 mm. The scanning distance is too small, heat accumulation is more prominent, and heat migration and mass migration in the layer are more obvious, so that the surface quality is reduced; and the scanning interval is too large, so that unfused powder is easy to appear on the surface, and the surface quality is easy to reduce. The inter-scan within this range contributes to an improvement in the surface quality of the material.

In alternative embodiments, the thickness of the laydown powder during the selective laser fusion forming process is 30-40 μm, such as 30 μm, 35 μm, or 40 μm. The powder thickness is favorable for good bonding between adjacent layers.

In an alternative embodiment, the scanning speed during the selective laser melting forming process is 160-1400mm/s, such as 160mm/s, 200mm/s, 300mm/s, 500mm/s, 800mm/s, 1000mm/s, 1200mm/s or 1400 mm/s. Setting the scanning rate to the above range is advantageous for obtaining a material with higher density.

In alternative embodiments, the laser power during the selective laser melting forming process is 60-200W, such as 60W, 100W, 150W, or 200W. When the laser power is more than 200W, microcracks due to thermal stress increase.

In an alternative embodiment, the spot diameter during selective laser fusion forming is 40-80 μm, preferably 80 μm.

On the basis, the raw materials are subjected to selective laser melting forming according to the process parameters, so that the prepared drill bit matrix material has the defects of high density and hardness, uniform tissue, no holes, microcracks and the like, is particularly suitable for drilling of medium-hard stratums, and solves the problems of complicated preparation means, long period, high production, incapability of forming complicated structures and the like in the traditional method.

In addition, the application also provides the application of the bit matrix material, for example, the bit matrix material can be used for preparing bit matrixes, further can be used for preparing PDC bit matrixes for oil and gas exploration, and is particularly suitable for drilling medium and hard formations.

In addition, this application still provides a drill bit matrix, and the preparation raw materials of this drill bit matrix include above-mentioned drill bit matrix material, and this drill bit matrix has better comprehensive mechanical properties, including hardness and bending strength etc..

Example 1

S1: nickel with an average particle size of 30 μm was selected to coat cast tungsten carbide powder with a nickel content of 12 wt%. The nickel-coated cast tungsten carbide powder is prepared by a chemical plating method. Wherein the cast tungsten carbide is spherical powder with a particle size of 30 μm and has WC and W₂Eutectic structure of C. The total carbon content in the cast tungsten carbide powder was 3.92 wt%.

S2: selecting spherical Cu-Ni alloy powder with the granularity of 500 meshes, wherein the Cu-Ni alloy powder comprises 75 mass percent of Cu and 25 mass percent of Ni.

S3: and weighing the nickel-coated cast tungsten carbide powder and the Cu-Ni alloy powder according to the mass ratio of 75: 25.

S4: and mixing the nickel-coated cast tungsten carbide powder and the CuNi alloy powder in a mixer for 2 hours to obtain printing raw material powder.

S5: and carrying out selective laser melting on the printing raw material powder, wherein the substrate is a stainless steel substrate, the working atmosphere is argon, the preheating temperature of the substrate is 100 degrees, the scanning interval is 0.15mm, the powder spreading thickness is 30 micrometers, the laser power is 180W, the laser scanning speed is 800mm/s, and the spot diameter is 60 micrometers.

The metallographic structure of the drill bit matrix material prepared in this example is shown in fig. 1, the electron microscope morphology of the nickel-coated cast tungsten carbide powder is shown in fig. 2, and the XRD pattern of the drill bit matrix material is shown in fig. 3.

As can be seen from the figure, the drill bit matrix material prepared by the embodiment has no defects of microcracks, air holes and the like, the hard phase is uniformly distributed in the matrix, the interface wettability and the interface bonding strength between the hard phase and the Cu-Ni matrix are better, the material density is higher and reaches 97.5%, the hardness reaches 51.74HRC, the hardness is improved by at least 25% compared with that of a powder metallurgy formed drill bit matrix material, and the bending strength is 754 MPa.

Example 2:

s1: nickel with an average particle size of 30 μm was selected to coat cast tungsten carbide powder with a nickel content of 12 wt%. The nickel-coated cast tungsten carbide powder is prepared by a chemical plating method. Wherein the cast tungsten carbide is spherical powder with a particle size of 35 μm and has WC and W₂Eutectic structure of C. The total carbon content in the cast tungsten carbide powder was 4.01 wt%.

S2: selecting spherical Cu-Sn alloy powder with the granularity of 400 meshes, wherein the Cu-Sn alloy powder comprises 75 mass percent of Cu and 25 mass percent of Sn.

S3: and weighing the nickel-coated cast tungsten carbide powder and the Cu-Sn alloy powder according to the mass ratio of 75: 25.

S4: and mixing the nickel-coated cast tungsten carbide powder and the Cu-Sn alloy powder in a mixer for 2 hours to obtain printing raw material powder.

S5: and carrying out selective laser melting on the printing raw material powder, wherein the substrate is a stainless steel substrate, the working atmosphere is argon, the preheating temperature of the substrate is 120 degrees, the scanning interval is 0.1mm, the powder spreading thickness is 30 micrometers, the laser power is 250W, and the scanning speed is 500 mm/s.

The density of the drill bit matrix material prepared by the embodiment reaches 95.3%, the hardness reaches 40.23HRC, and the bending strength is 635 MPa.

Comparative example

In conclusion, the drill bit matrix material provided by the application can realize the uniform distribution of the hard phase in the matrix, improve the bonding force between the hard phase and the bonding phase, form a good interface layer, and has hardness higher than that of the material prepared by the traditional method. The preparation method is simple and easy to operate, can ensure that the prepared drill bit matrix material has higher density and hardness, uniform tissue and no defects of holes, microcracks and the like, is particularly suitable for drilling medium-hard strata, and solves the problems of complicated preparation means, long period, high production, incapability of forming complicated structures and the like in the traditional method. The composite material is used for preparing a drill bit matrix, so that the drill bit matrix has better comprehensive mechanical properties.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. The drill bit matrix material is characterized by being mainly obtained by selective laser melting and forming of drill bit matrix powder;

the drill bit matrix powder comprises copper alloy powder and spherical nickel-coated cast tungsten carbide composite powder with a core-shell structure or spherical nickel-copper-coated cast tungsten carbide composite powder with a core-shell structure; the drill bit matrix powder contains 30-85% of the nickel-coated cast tungsten carbide composite powder or the nickel-copper-coated cast tungsten carbide composite powder and 15-70% of the copper alloy powder;

the granularity of the nickel-coated cast tungsten carbide composite powder or the nickel-copper-coated cast tungsten carbide composite powder is 15-53 mu m; the nickel-coated cast tungsten carbide composite powder or the nickel-copper-coated cast tungsten carbide composite powder contains 2-15% by mass of nickel and 5-10% by mass of copper;

the powder of cast tungsten carbide has WC and W₂A eutectic structure of C; the particle size of the powder of the cast tungsten carbide is 15-45 μm; the total carbon content in the cast tungsten carbide powder is 3.7-4.2% by mass percent;

the copper alloy powder is spherical powder with the granularity of 325-500 meshes;

the working atmosphere of the selective laser melting forming comprises at least one of argon and nitrogen; the included angle between layers in the selective laser melting forming process is 30-75 degrees; the preheating temperature of the substrate is 80-150 ℃; the scanning distance is 0.1-0.2 mm; the powder spreading thickness is 30-40 μm; the scanning speed is 160-1400 mm/s; the laser power is 60-200W; the diameter of the light spot is 40-80 μm.

2. The drill bit matrix material according to claim 1, wherein the nickel-clad cast tungsten carbide composite powder or the nickel-copper-clad cast tungsten carbide composite powder is prepared by an electroless plating method.

3. The bit matrix material of claim 1, wherein the cast tungsten carbide in the nickel-clad cast tungsten carbide composite powder or the nickel-copper-clad cast tungsten carbide composite powder is a spherical powder.

4. The bit matrix material of claim 3, wherein the powder of cast tungsten carbide has a microhardness of 2600-_0.1。

5. The drill bit matrix material of claim 1, wherein the copper alloy comprises a Cu-Ni alloy or a Cu-Sn alloy.

6. The drill bit matrix material according to claim 5, wherein the copper alloy is a Cu-Ni alloy containing, in mass percent, 50-85% of Cu and 15-50% of Ni.

7. The bit matrix material according to claim 5, wherein the copper alloy is a Cu-Sn alloy containing, in mass percent, 50-85% of Cu and 15-50% of Sn.

8. The drill bit matrix material according to claim 1, wherein the copper alloy powder is prepared by means of gas atomization.

9. The drill bit matrix material of claim 1, wherein the density of the drill bit matrix material is 95.3-97.5%.

10. The drill bit matrix material of claim 1, wherein the hardness of the drill bit matrix material is 40.23-51.74 HRC.

11. A method of preparing a drill bit matrix material according to any one of claims 1 to 10, comprising the steps of: and carrying out selective laser melting forming on the drill bit matrix powder.

12. The method according to claim 11, wherein the copper alloy powder and the spherical nickel-clad cast tungsten carbide composite powder or the nickel-copper-clad cast tungsten carbide composite powder having a shell-core structure are mixed for 2 to 4 hours and then subjected to selective laser fusion forming.

13. The method of claim 12, wherein the mixing is performed in a blender.

14. The method of claim 11, wherein the substrate for selective laser fusion molding comprises a stainless steel substrate or TC4 substrate.

15. The method of claim 11, wherein the working atmosphere for selective laser fusion forming comprises at least one of argon and nitrogen; the included angle between layers in the selective laser melting forming process is 30-75 degrees;

preheating the substrate at 80-150 ℃ in the selective laser melting forming process;

the scanning distance in the selective laser melting forming process is 0.1-0.2 mm;

the powder spreading thickness is 30-40 μm in the selective laser melting forming process;

the scanning speed in the selective laser melting forming process is 160-1400 mm/s;

the laser power is 60-200W in the selective laser melting forming process;

the spot diameter is 40-80 μm during selective laser melting forming.

16. Use of a drill bit matrix material according to any one of claims 1 to 10 for preparing a drill bit matrix.

17. The use according to claim 16 for the preparation of PDC bit casings for oil and gas exploration.

18. A drill bit matrix, wherein a raw material for preparing the drill bit matrix comprises the drill bit matrix material according to any one of claims 1 to 10.