Super-high thermal conductivity and low thermal expansivity diamond composite material and preparation method thereof

Abstract

The invention discloses a super-high thermal conductivity and low thermal expansivity diamond composite material and a preparation method thereof, and belongs to the field of high-performance functional materials. The composite material consists of at least two phases of high thermal conductivity diamond grains and high thermal conductivity metals or alloy materials. The preparation method for the composite material comprises the following steps of: putting high thermal conductivity sheet or block metals or alloy materials on the high thermal conductivity diamond powder grains, loading, sealing, performing vacuum heat treatment, and performing melt infiltration sintering at certain high temperature under high pressure to make high thermal conductivity metals melted and infiltrated in the diamond grains so as to form the super-high thermal conductivity and low thermal expansivity composite material. The method makes high thermal conductivity nonmetal materials and high thermal conductivity metal materials firmly combined, so the composite material has the compactness of over 99 percent, and the thermal conductivity of 600 to 800W/(m.K); the thermal expansivity (less than 5ppm/K) matched with an electronic device can ensure that a workpiece works stably for a long time under the condition of high heating density; and the composite material has wide industrial application prospect.

Description

technical field [0001] The invention belongs to the field of high-performance electronic packaging functional materials, and in particular provides a diamond-reinforced metal composite material with ultra-high thermal conductivity and low thermal expansion coefficient and a preparation method thereof. Background technique [0002] The high power density devices used in communication satellites and the plasma materials used in nuclear fusion devices will generate and accumulate a large amount of heat during operation. High demands were made. Many electronic components of aerospace vehicles need to work normally at an ambient temperature of 40-60°C, so the heat generated during the operation of the instrument must be discharged in time. One of the primary problems brought about by the improvement of chip integration and packaging density is that the unit power of the device continues to increase, and the heat generation continues to increase, which makes the working environme...

AI Technical Summary

Problems solved by technology

The Lawrence Livermore National Laboratory of the United States and Sun Microsystems developed a diamond-copper composite material as early as 1995, called Dymalloy [2] , the volume fraction of type I diamond is 55%, the diamond powder coated with metal on the surface is put into the mold for compaction, and then the copper alloy is infiltrated in vacuum, the thermal conductivity of the prepared composite material reaches 420W / m·k, and the material has a certain Plastic, easy to process, but because of the near net forming process, the surface finish is poor, if there is a requirement for surface finish, it needs to be plated or polished