Tribological behavior of aluminum matrix composites containing complex metallic alloys AlCuFeB or AlCuFeCr particles

The tribological behavior of sintered aluminum metal matrix composites (MMCs) containing various volume fractions of particles made of complex metallic alloys (CMAs) was investigated in a reciprocating dry sliding tribo-tester operated in ambient air against 10 mm diameter Al2O3 balls. The Al-based MMCs tested contained either 15 μm size AlCuFeB or 25 μm size AlCuFeCr-particles. An improvement in the dry sliding wear resistance of aluminum was achieved by the incorporation of these CMA-particles acting as a second phase reinforcement. The wear resistance depends on the volume fraction of CMA-particles but not on their composition, nano-hardness or size. These Al-based MMCs containing CMA-particles exhibit however a higher coefficient of friction than pure aluminum under dry sliding against a ceramic counterbody. A clear correlation was not found between composition, nano-hardness, size or volume percent of CMA-particles, and coefficient of friction. The dominant wear mechanisms active on MMCs containing either AlCuFeB or AlCuFeCr-particles are abrasion and adhesion, but abrasion dominates in the case of Al-MMCs containing AlCuFeCr-particles.