Fabrication of Ni/WC composite with two distinct layers through centrifugal infiltration combined with a thermite reaction

A simple and energy-efficient method combining a thermite reaction and centrifugal infiltration was applied to produce Ni/WC composites. Driven by a centrifugal force, the molten Ni in-situ produced by a thermite reaction infiltrated into a porous preform of WC powder compact. After solidification, a Ni/WC composite was obtained with two metallurgically bonded layers. Both of the two layers were composed of Ni and WC but with different contents. In different regions of the sample, WC particles with different morphologies and sizes were observed, which were caused by the competition of growth and relaxation of WC particles. The WC-rich layer showed an average hardness of 81.5 HRA, and the hardness of the Ni-rich layer gradually decreased from 61.4 HRA to 53.9 HRA.