Microstructure and properties of Y2O3/Cu composites fabricated by a novel liquid phase in situ reactive synthesis process

Cu–Y2O3 composites were prepared by a secondary mechanical ball milling process and liquid phase in situ reaction and then sintered by the spark plasma sintering (SPS) consolidation technique. The microstructure and mechanical properties were studied using an X-ray powder diffractometer, scanning electron microscope, tensile tester, and Vickers hardness tester. The results showed that the added yttrium was converted into Y2O3, and the obtained Y2O3 nano-particles were uniformly distributed in the copper matrix, their mean size was 5.0 nm, and the cubic Y2O3 phase was coherent with the copper matrix, which indicated (422)Y2O3// (1‾11) Cu and [011‾] Y2O3// [11‾2] Cu orientation relationship. With the addition of Y, the mechanical properties of the composite materials were improved, and the hardness of 10 vol% Y2O3 was increased by 192.0%. Its tensile strength increased by 168.2% compared to pure copper.