Abstract:Nano-structured alumina (n-Al₂O₃) powders prepared by spray drying granulation and micro-structured alumina (m-Al₂O₃) powders by fused-crushed method were used to fabricate Al₂O₃ reinforced CuAl coatings. The microstructure and phase composition of the coatings were analyzed, and their tribological properties were investigated in comparison with those of the CuAl coating. In both CuAl/n-Al₂O₃ and CuAl/m-Al₂O₃ coatings, the reinforcing Al2O3 exists as well-flattened splats, and shows good interfacial compatibility with the bronze matrix. The alumina existed as amorphous and gamma-Al2O3 phase in the CuAl/m-Al₂O₃ composite coating, while alpha-Al₂O₃ phase was contained in the CuAl/n-Al₂O₃ coating. Although the CuAl/n-Al2O3 composite coating gives a highest friction coefficient at all loads, it possesses superior wear-resistance as compared with the CuAl/m-Al₂O₃ coating and pure CuAl coating.

KeyWords Plus:BRONZE; WEAR; BEHAVIOR; FRICTION; STEEL; POWDERS

Published in TRIBOLOGY INTERNATIONAL, 101 255-263; 10.1016/j.triboint.2016.04.034 SEP 2016