Fabrication of three layered W-Cu functionally graded composite via spark plasma sintering

In this study, a three layered W-Cu functionally graded composite (FGC) was fabricated using spark plasma sintering method (SPS) at 985 °C. The W-Cu FGC specimen was fabricated with the content of tungsten as 0%, 50%, and 100% Vol.% in each layer, respectively. moreover, two W-Cu composites having 75 and 50 Vol.% W have been synthesized by conventional cold pressing and sintering for comparison purposes. The results of secondary electron microscopy (SEM) as well as quantitative image analysis revealed up to 97% densification. The composition in SEM images were determined using Energy Dispersive X-ray mapping (EDX). The hardness of middle layer (111HV30) was 40% higher than that of W-50 Vol.% Cu composite (79HV30). The hardness of pure copper layer (46HV30) was 30% higher than of the commercial copper (35HV30). The relative density of intermediate layer of W-Cu FGC 8.66% improved by using SPS, in comparison to W-50 Cu composite sample. These can be attributed to the positive effect of SPS on the sintering behavior of W-Cu composite.