METHOD FOR PRODUCING A HIGHLY HEAT-CONDUCTIVE ALUMINIUM-GRAPHITE COMPOSITE Russian patent published in 2021 - IPC C22C47/12 C22C49/06 C22C101/10 

FIELD: composite materials.

SUBSTANCE: invention relates to production of highly heat-conductive composite aluminium-graphite materials and can be used in electronics, instrument manufacture, power engineering. The method for producing a highly heat-conductive composite aluminium-graphite material includes preparing a mixture of powders, containing highly crystalline flaked graphite with a particle size in the plane of 100 mcm to 1000 mcm and a thickness of 5 mcm to 20 mcm with an aspect ratio of 5 to 200 and a degree of crystallinity of at least 97% and silicon powder and/or aluminium alloy powder with 3 to 12 wt.% silicon, with an average particle size of 1 to 20 mcm at a ratio of components in the mixture, wt.%: flaked graphite 40 to 80, silicon powder and/or aluminium alloy 20 to 60, producing a porous graphite preform therefrom by layer-by-layer vibration compacting in a metal mould with a thickness of filling of each layer of 3 to 8 mm, a vibration frequency of 80 to 120 Hz, a compaction pressure of 150 to 250 kPa, a compaction duration for each layer of 60 to 90 seconds, heating the mould with the graphite preform to a temperature of 550 to 650°C in the presence of air, impregnating the porous graphite preform with an aluminium alloy melt under pressure imparted by a hydraulic press. The resulting composite material contains 40 to 80 vol.% flaked crystalline graphite and exhibits a heat conductivity in a plane perpendicular to the direction of compacting of 400 to 720 W/mK and the thermal expansion coefficient of 15*10-6 K-1-4*10-6 K-1.

EFFECT: invention is aimed at increasing the heat conductivity of the material while simplifying the process and reducing the time for production thereof.

6 cl, 7 dwg, 4 ex