Investigation on microstructure and properties of TiC0.5-Al2O3/Cu composites fabricated by a novel in-situ reactive synthesis

Abstract

In this study, a novel TiC0.5-Al2O3/Cu composite was successfully prepared by spark plasma sintering using a mixture of the Ti2AlC, Cu2O and Cu powders as starting materials. The micron-sized Ti2AlC particles were decomposed into the submicron TiC0.5 grains during the sintering process. Further, Al atoms diffusing out of Ti2AlC entered Cu matrix and subsequently reacted with Cu2O to form Al2O3 grains. Due to the distribution of the submicron TiC0.5 and Al2O3 grains in the Cu matrix, the hardness increased on enhancing Ti2AlC content from 1 to 5 wt%, however, the electrical conductivity was observed to decrease. TiC0.5 and Al2O3 particles significantly improved the compression properties, and the ductility was maintained at a comparatively high level. On enhancing Ti2AlC content from 1-5 wt%, the yield strength of the material (σ0.2) increased from 118 MPa to 241 MPa, and the composite remained intact even after 25% strain.