Effect of nano-Y2O3 on the microstructure and mechanical properties of Cu-10W composites prepared by spark plasma sintering

Cu-W composites with high strengths and high conductivities have diverse applications. At present, studies on Cu-W composites with low W content (<50 wt%) are scarce. In this study, Cu-10 wt% W (hereinafter referred to as Cu-10W) composites reinforced by nano-Y2O3 particles with various Y2O3 contents were prepared via ball milling and spark plasma sintering (SPS). The effects of different Y2O3 contents (1, 2 and 3 wt%) on the microstructure and mechanical properties of the composites were studied. The results show that the Y2O3 and W particles were uniformly distributed in the Cu matrix. With increasing Y2O3 content, the distribution of Y2O3 changed from dispersion to agglomeration, and the grain size gradually decreased. The hardness and compressive yield strength increased gradually. In addition, the electrical conductivity was maintained above 81.76 %IACS (as stipulated by the International Annealed Copper Standard). For the Y2O3 content of 2 wt%, the density and relative density of the composites reach the maximum values of 9.18 g/cm3 and 98.65%, respectively. At this time, the tensile strength reaches 353.8 MPa. The combination between the matrix and Y2O3 was good, and the composites showed the best comprehensive performance.