Fabrication of W/Cu graded heat-sink materials by electroless plating and powder metall

Abstract:

The W/Cu graded heat-sink materials with high density were fabricated by electroless plating and powder metallurgy. The microstructure, interface and fracture of the graded heat-sink materials were observed using the field emission scanning electron microscope (FESEM). The mechanical properties of the materials such as bending strength and hardness were determined. The experimental results showed that the structure of each layer was uniform and dense. The components of the cross-section presented a graded distribution. There was no obvious interface among layers. The relative density of three-layer W/Cu graded heat-sink materials reached 99.2%. The average values of microhardness of radiating layer, transitional layer and sealing layer were HV200, 210 and 240, respectively. It is indicated through the experimental results of bending strength that the bending strengths of the sealing layer and the radiating layer as the load-bearing surfaces were 428.5 MPa and 480.7MPa, respectively.