Wear resistance and tribological features of pure aluminum and Al-Al₂O₃ composites consolidated by high-pressure torsion

Ultrafine-grained pure Al and Al-based composites with 10 and 20vol% of Al₂O₃ were produced by cold consolidation of powders using high-pressure torsion (HPT). Ball-on-disc wear resistance of Al was improved by HPT when compared to its coarse-grained counterpart processed with H24 treatment (cold rolling followed by low-temperature annealing). Wear width decreased but wear depth and wear volume increased with the addition of Al₂O₃ to the Al matrix. The wear mechanism was mainly due to adhesion in Al and Al-Al₂O₃ composites. It was found that the variation of wear width can be represented by a unique function of the ratio of load/hardness in consistency with the Reye's hypothesis and the Holm and Archard relationships. However, the variation of wear depth was inconsistent with the hardness variations.