Role of B2O3 and CaO in Al2O3 matrix composite: In-situ phases, density, hardness and wear resistance

A novel set of Al2O3-B2O3-CaO composites were manufactured using a cold press-sintering. The B2O3 content in the was varied from 5 to 20 wt% and 2 CaO added composites. Dry sliding tests conducted against an alumina ball at 10–95% relative humidity. presence in-situ formed aluminum borate composite enhanced micro-hardness wear resistance, whereas humidity-sensitive phase reduced friction. Furthermore, addition improved density upto ~92% which also led significant improvement hardness resistance. However, friction negatively affected. mechanism for resistance is demonstrated by considering crystal-chemical approach polarization theory double oxide systems.