阅读说明：本技术 一种金刚石颗粒增强金属基复合材料及其制备方法和应用 (Diamond particle reinforced metal matrix composite material and preparation method and application thereof ) 是由 史长明 于 2020-04-30 设计创作，主要内容包括：本发明公开了一种金刚石颗粒增强金属基复合材料及其制备方法和应用。该方法包括以下步骤：(1)制备界面层；(2)制备金属层；(3)预成型；(4)致密化处理。本发明采用预成型和致密化处理相结合的两步固相法烧结互为补充、扬长避短,不仅保留了固相烧结法可制备更小颗粒度材料的特点,且单批次制备的材料尺寸更大,可达厘米级以上厚度,生产效率更高,成本大幅下降。所制得的材料热导率较高、热膨胀系数可调,均匀性、可靠性更好,且能直接用电火花线切割进行加工。同时,致密化处理前的预成型可避免采用直接热等静压烧结包套变形过大而导致材料浪费大的问题,材料利用率更高。(The invention discloses a diamond particle reinforced metal matrix composite material and a preparation method and application thereof. The method comprises the following steps: (1) preparing an interface layer; (2) preparing a metal layer; (3) preforming; (4) and (5) densification treatment. The invention adopts the two-step solid phase sintering method combining the pre-forming and the densification treatment to complement each other, improve the advantages and avoid the disadvantages, not only keeps the characteristic that the solid phase sintering method can prepare materials with smaller granularity, but also has larger material size which can reach the thickness of centimeter level or more, has higher production efficiency and greatly reduces the cost. The prepared material has high thermal conductivity, adjustable thermal expansion coefficient, better uniformity and reliability, and can be directly processed by wire cut electrical discharge machining. Meanwhile, preforming before densification treatment can avoid the problem of large material waste caused by excessive deformation of the sintering sheath by adopting direct hot isostatic pressing, and the material utilization rate is higher.)

1. A preparation method of a diamond particle reinforced metal matrix composite material is characterized by comprising the following steps:

(1) preparing an interface layer: depositing metal and/or carbide on the surface of diamond particles with the particle size of 0.1-70 mu m to form an interface layer consisting of the metal and/or the carbide; the metal is at least one of Ti, Cr, W, Zr, B, Si, Mo, Nb and V; the carbide is TiC and Cr₂C₃At least one of WC, ZrC, BC, SiC, MoC, NbC and VC;

(2) preparing a metal layer: continuously depositing metal on the interface layer to prepare diamond particle powder coated by the interface layer and the metal layer; the volume fraction of the diamond is 30.001% -99.999%; the metal is at least one of Cu, Al, Ag, Au, Mg, Sn and Zn;

(3) preforming: placing the diamond particle powder prepared in the step (2) in a mould for preforming to obtain a blank;

or uniformly mixing the diamond particle powder prepared in the step (2) with metal powder with the particle size of 1-50 mu m, and placing the mixture in a mold for preforming to obtain a blank; the volume fraction of the diamond particles after mixing is 30-80%; the metal powder is at least one of metal Cu, Al, Ag, Au, Mg, Sn, Zn or alloy;

(4) densification treatment: and (3) placing the blank obtained through the preforming treatment in a closed environment with the pressure of 50-300 MPa, heating to 500-1100 ℃ at the heating rate of 1-50 ℃/min, sintering, keeping the temperature and the pressure for 5-300 min, and then cooling and reducing the pressure.

2. The method for producing a diamond particle-reinforced metal matrix composite according to claim 1, wherein the interface layer has a thickness of 1 to 5000 nm.

3. The method for producing a diamond particle-reinforced metal matrix composite according to claim 1, wherein when the interface layer is formed of only a metal, a carbide layer formed of the metal and diamond particles is also present between the interface layer and the diamond particles.

4. The method for producing a diamond particle-reinforced metal matrix composite according to claim 1, wherein the diamond particles have a particle diameter of 10 to 65 μm.

5. The method of producing a diamond particle-reinforced metal matrix composite according to claim 4, wherein the diamond particles have a particle size of 65 μm.

6. The method of preparing a diamond particle reinforced metal matrix composite according to claim 1, wherein the pre-forming process is cold press forming, cold isostatic pressing, vacuum hot press sintering or spark plasma sintering.

7. The method for producing a diamond particle-reinforced metal matrix composite according to claim 1, wherein the densification process comprises: and putting the blank into a stainless steel sheath, vacuumizing, sealing and then carrying out hot isostatic pressing, or directly carrying out hot isostatic pressing on the blank, wherein the heating speed is 5 ℃/min, the sintering temperature is 800 ℃, the pressure is 100MPa, and the pressure maintaining time is 100 min.

8. The method of preparing a diamond particle reinforced metal matrix composite according to claim 1, wherein the alloy in step (3) consists of one or more of the metals Cu, Al, Ag, Au, Mg, Sn, Zn and one or more of the metals Ti, Cr, W, Zr, B, Si, Mo, Nb, V.

9. A diamond particle reinforced metal matrix composite material produced by the method of any one of claims 1 to 8.

10. The use of a diamond particle reinforced metal matrix composite according to claim 9 for the preparation of an electrically and thermally conductive substrate, a soaking plate, a cold plate, a heat spreader or a heat sink material for a semiconductor device.

Technical Field

The invention belongs to the technical field of metal-based composite materials, and particularly relates to a diamond particle reinforced metal-based composite material and a preparation method and application thereof.

Background

The power semiconductor device can generate a large amount of joule heat in the working process, if the heat can not be dissipated in time, the junction temperature of the semiconductor chip can be continuously increased, the performance and the service life of the device are influenced, and the chip can be directly burnt seriously. The heat conductivity of the heat sink materials such as W/Cu, Mo/Cu, SiC/Al and the like which are widely used at present is only 170-230W/mK, and the packaging and using requirements of a higher-power device are difficult to meet. Therefore, the heat conducting substrate material has become a bottleneck problem of the continuous development of the semiconductor power device to higher power.

Diamond particle reinforced metal matrix composites, such as diamond/copper, diamond/aluminum, diamond/silver, diamond/magnesium, etc., have received much attention from many research, production, and application organizations both at home and abroad in recent years due to their higher thermal conductivity and adjustable thermal expansion coefficient, but such materials have been used to a small extent in only some fields to date. The reason for limiting the larger-scale popularization and application of the medicine is as follows:

(1) the preparation efficiency, the material uniformity and the density are mutually contradictory and can not be unified. The methods generally used at present are of three types, namely high-temperature high-pressure methods, infiltration methods and solid-phase sintering methods. Although the density of the material prepared by the high-temperature and high-pressure method is higher, the production efficiency is extremely low and the cost is high. Although the infiltration method is a method of obtaining a material having a relatively high density at a low cost, the density of diamond is lower than that of metal (alloy), and thus the diamond skeleton collapses during infiltration, and the diamond floats on the surface of metal to cause a phenomenon of uneven distribution. Solid-phase sintering methods, such as vacuum hot-pressing sintering, spark plasma sintering, vacuum sintering after cold press forming and the like, have relatively high production efficiency, but the density of the prepared material is not high, and the air tightness of the material is influenced. There is also a problem of material uniformity if diamond powder is mixed with metal powder and then sintered.

(2) The cutting difficulty is large, the surface processing is difficult, and the surface finish is poor. Because diamond is the material with the highest hardness in nature, the diamond particle reinforced metal matrix composite material cannot adopt the common mechanical cutting or linear cutting mode, and only can adopt water jet cutting or laser cutting, so that the cutting cost is high, the cutting quality is poor, and the subsequent grinding processing amount is large. However, the hardness difference between diamond and the metal substrate is very large, the grinding processing is very difficult, the surface finish is poor, great inconvenience is brought to subsequent packaging, and even the diamond can not be used. The difficulty of cutting, the difficulty of surface processing and the poor smoothness become important obstacles for limiting the large-scale application of the material. The preparation method adopts a near-net-shape forming mode, has extremely low production efficiency and is not beneficial to large-scale application and popularization.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides a diamond particle reinforced metal matrix composite material and a preparation method and application thereof, which can effectively solve the problems of poor material uniformity, low density, incapability of wire-electrode cutting by electric fire wires and high processing difficulty in the existing preparation process.

In order to achieve the purpose, the technical scheme adopted by the invention for solving the technical problems is as follows:

a preparation method of a diamond particle reinforced metal matrix composite material comprises the following steps:

(1) preparing an interface layer: depositing metal and/or carbide on the surface of diamond particles with the particle size of 0.1-70 mu m to form an interface layer consisting of the metal and/or the carbide; the metal is at least one of Ti, Cr, W, Zr, B, Si, Mo, Nb and V; the carbide is TiC and Cr₂C₃At least one of WC, ZrC, BC, SiC, MoC, NbC and VC;

(2) preparing a metal layer: continuously depositing metal on the interface layer to prepare diamond particle powder coated by the interface layer and the metal layer; the volume fraction of the diamond is 30.001% -99.999%; the metal is at least one of Cu, Al, Ag, Au, Mg, Sn and Zn;

the diamond particles coated by the interface layer and the metal layer are formed by compounding diamond particles with the particle size of 0.1-70 mu m, the interface layer with the surface thickness of 1-5000 nm and the metal layer continuously deposited on the interface layer.

The interface layer can be formed by depositing at least one of metal Ti, Cr, W, Zr, B, Si, Mo, Nb and V on the surfaces of diamond particles by one or more of chemical vapor deposition, vacuum evaporation, magnetron sputtering, multi-arc ion plating, sol-gel, salt bath plating, chemical plating or electroplating, generating corresponding carbide layers through high-temperature reaction of subsequent process steps, and forming the interface layer together;

carbide TiC and Cr can also be directly deposited on the surface of the diamond₂C₃One or more of WC, ZrC, BC, SiC, MoC, NbC and VC, or a layered or dispersed composite coating consisting of the carbide and the metal is used as an interface layer.

The metal layer is one or more of metal Cu, Al, Ag, Au, Mg, Sn and Zn, and the part of metal layer is used as the whole or part of metal matrix in the composite material and can be prepared by one or more methods of chemical vapor deposition, vacuum evaporation, magnetron sputtering, multi-arc ion plating, sol-gel, salt bath plating, chemical plating or electroplating.

(3) Preforming: placing the diamond particle powder prepared in the step (2) in a mould for preforming to obtain a blank; or uniformly mixing the diamond particle powder prepared in the step (2) with metal powder with the particle size of 1-50 mu m, and placing the mixture in a mold for preforming to obtain a blank; the volume fraction of the mixed diamond particles is 30-80%;

the metal powder may be one or more of Cu, Al, Ag, Au, Mg, Sn, and Zn, or an alloy, a pseudo alloy, a mixture, or an intermetallic compound formed by adding one or more of Ti, Cr, W, Zr, B, Si, Mo, Nb, and V to the above metal.

(4) Densification treatment: and (3) placing the blank obtained through the preforming treatment in a closed environment with the pressure of 50-300 MPa, heating to 500-1100 ℃ at the heating rate of 1-50 ℃/min, sintering, keeping the temperature and the pressure for 5-300 min, cooling and reducing the pressure, and removing the sheath (if any), thereby obtaining the diamond particle reinforced metal matrix composite material designed by the invention.

Further, the thickness of the interface layer is 1 to 5000 nm.

Further, when the interface layer is formed of only a metal, a carbide layer formed of the metal and diamond particles is also present between the interface layer and the diamond particles.

Further, the particle size of the diamond particles is 10-65 μm.

Further, the particle diameter of the diamond particles was 65 μm.

Further, the pre-forming treatment process is cold press forming, cold isostatic pressing, vacuum hot pressing sintering or spark plasma sintering.

Further, the specific process of densification treatment is as follows: and putting the blank into a stainless steel sheath, vacuumizing, sealing and then carrying out hot isostatic pressing, or directly carrying out hot isostatic pressing, wherein the heating speed is 5 ℃/min, the sintering temperature is 800 ℃, the pressure is 100MPa, and the pressure maintaining time is 100 min.

The diamond particle reinforced metal matrix composite material prepared by the method comprises diamond particles, a metal matrix and an interface layer on the interface between the metal matrix and the diamond particles. Wherein the particle size of the diamond particles is 0.1-70 μm, and the diamond particles are uniformly dispersed in the metal matrix.

The metal matrix is one or more of Cu, Al, Ag, Au, Mg, Sn and Zn, or an alloy, a pseudo alloy, a mixture or an intermetallic compound formed by adding one or more of Ti, Cr, W, Zr, B, Si, Mo, Nb and V on the basis of the metal matrix. The interface layer is composed of one or more of Ti, Cr, W, Zr, B, Si, Mo, Nb and V and carbide corresponding to the one or more of Ti, Cr, W, Zr, B, Si, Mo, Nb and V; or directly made of TiC and Cr₂C₃One or more carbides of WC, ZrC, BC, SiC, MoC, NbC and VC, and the thickness of the interface layer is 1-5000 nm.

The diamond particle reinforced metal matrix composite is used for preparing an electric and heat conducting substrate, a soaking plate, a cold plate, a radiator or a heat sink material of a semiconductor device.

The invention has the beneficial effects that:

1. the distribution of the diamond particles of the material prepared by the technical scheme provided by the invention is nearly completely uniform. Homogeneous materials are arranged among the diamond particles with the coating or between the surfaces of the diamond particles with the coating and the surfaces of the metal matrix powder particles, so that the phenomenon of uneven powder mixing is improved or basically eliminated, and in addition, the powder is always kept in a solid state in the pre-forming and densification processing processes, so that the diamond particles in the prepared material are almost completely and uniformly distributed.

2. The composite material prepared according to the technical scheme provided by the invention has higher thermal conductivity and adjustable thermal expansion coefficient. Firstly, the thermal conductivity of the diamond is as high as 1100-; secondly, the interface layer arranged between the metal matrix and the diamond can obviously improve the wettability between the matrix metal and the diamond, thereby reducing the interface thermal resistance; thirdly, the densification treatment process can further improve the density of the composite material and reduce the porosity, thereby improving the heat-conducting property of the composite material. In addition, the thermal expansion coefficient of the material can be adjusted to match that of the semiconductor chip by adjusting the thickness of the metal layer and the mass of the added metal powder.

3. The interface between the diamond and the substrate is more continuous and has higher reliability. As the carbide layer between the diamond and the matrix is generated by chemical vapor deposition, vacuum evaporation, magnetron sputtering, multi-arc ion plating, sol-gel, molten salt plating, chemical plating or electroplating in-situ generation or reaction after a metal layer is deposited, the coating and the diamond can be completely plated and have uniform thickness, thereby ensuring the continuous distribution of a carbide interface layer and higher reliability of the obtained composite material.

4. The densification treatment can fully ensure that the prepared material has higher density. By utilizing the characteristics of uniform stress and large pressure in all directions in the sintering process of the hot isostatic pressing technology, the density of the single solid-phase sintered composite material is obviously improved, and the obtained material has better air tightness.

5. The production efficiency is higher, and the preparation cost is lower. The two-step solid phase sintering method combining pre-forming and densification processing is adopted to complement each other and improve the advantages and the disadvantages. Compared with a high-temperature high-pressure method and a pressure infiltration method, the method not only keeps the characteristic that a solid-phase sintering method can be used for preparing materials with smaller granularity, but also enables the size of the materials prepared in a single batch to be larger and to reach the thickness of centimeter level or more, the production efficiency is higher, the labor cost and the energy consumption cost are lower, and the preparation cost is greatly reduced. Meanwhile, preforming before densification treatment can avoid the problem of large material waste caused by overlarge deformation of the sheath when direct hot isostatic pressing sintering is adopted, and the material utilization rate is higher.

6. The difficulty and the cost of cutting and grinding processing are reduced, and the processing quality is higher. The diamond granularity is properly reduced, and the diamond particles can be punctured to generate a micro-area blasting effect when electric sparks are discharged, so that the conventional wire-cut electrical discharge machining is realized, and the cutting difficulty and the cutting cost of materials are greatly reduced. Meanwhile, as the linear cutting does not generate cutting inclination due to laser cutting and water jet cutting divergence angles, the verticality of the cutting surface is better; and a cutting surface with higher surface evenness can be obtained by further adjusting the parameters of the linear cutting process, and the quality of the cutting surface is higher. Because the granularity of the diamond is reduced, the grinding amount is smaller and the roughness of the ground surface is easier to reduce in subsequent grinding processing, so that the grinding cost is reduced and the grinding quality is improved.

7. The process is mature, has high feasibility and has large-scale production and popularization conditions. The raw materials used in the technical scheme provided by the invention are all the materials sold in the market, and the used processes and equipment are mature technologies and conventional equipment, so that the feasibility is high, and the large-scale production and application and popularization are facilitated.

Drawings

FIG. 1 is a process flow diagram of the present application.

Detailed Description

The following description of the embodiments of the present invention is provided to facilitate the understanding of the present invention by those skilled in the art, but it should be understood that the present invention is not limited to the scope of the embodiments, and it will be apparent to those skilled in the art that various changes may be made without departing from the spirit and scope of the invention as defined and defined in the appended claims, and all matters produced by the invention using the inventive concept are protected.