Tungsten And Copper Heat Sink Materials, Preparation Of New Technology Research

W-Cu composite is the first consideration in the military electronic device, especialy in the solid phased-array radar, because its component could be adjusted so as to satisfy the requirement of the thermal expansion coefficient(CET) and thermal conductivity(TC).The property of the W-Cu composites which were produced by the Institue of Electronic Materials of Central South University was comparing to the international standard. But during the large batch production, a lot of new problems appeared, such as the limitation of Hydrostatic Forming and there were holes in the surface, blackspots on the Ni cladding, etc.This article analyzes these problems by HVC that can improve the relative density of tungsten billet, Hot-forging process of the W-Cu material increase in density,add-induced infiltration of copper to optimizing the infiltrating process of tungsten skeleton. Furthermore, the mic-rostructure of the composites were observed by using scanning electronic microscopy(SEM).The results are showed as follows:1)Through high velocity compaction of Tungsten skeleton at room temperature,600℃,950℃.With the compaction of the temperature rise, green density increases.As a result with the number of high-speed to suppress the increase,green density be improved.2) By high velocity compaction(HVC) can get the relative density of the W skeleton is 80.65%.By technology of high velocity compaction combined with melt infiltration process can get relative density of 90W-10Cu materials reached 99.5%,thermal conductivity is 175W/(m·K), Hermeticity and Coefficient of thermal expansion(CTE) and other indicators have reached the appropriate heat sink material requirements.3)In four different forging temperature, forging on the W-Cu materials,experiments show that the most appropriate tungsten copper alloy forging temperature of 950℃.The hot forging's deformation of Tungsten-copper alloy is largest at 950℃.Density increases in the largest and degree of densification is best.4) Add 3% coppe powder induced in 2.4μm tungsten powder. Through isostatic pressing was the relative density of more than 55% of the compacts,.Through high velocity compaction of Tungsten skeleton at 950℃,the relative density of up to 72.46% or more, consistent with preparation W85/Cu alloy requirements.By technology of high velocity compaction combined with melt infiltration process can get relative density of W85Cu materials reached 98.5%,thermal conductivity is 186W /(m·K),Hermeticity is 1 X 10-9Pa·m3s-1.