ZA-27 Alloy Composites Reinforced with Al2O3 Particles

Abstract

The ZA-27 alloy is present in the world as a material of very good tribological properties for the conditions of high loads and small sliding speeds. In recent years the research interest is increasing for development of the composite materials with that alloy as a substrate with addition of the Al2O3, graphite and SiC particles as the reinforcement. In this paper are presented results of tribological investigations of composites with substrate made of the ZA-27 alloy reinforced by the Al2O3 particles of sizes 12 and 250 μm in quantities of 3.5 and 10 mass %. The tribological investigations were conducted on the block-on-disc tribometer with variation of the three levels of the contact load (2 daN, 5 daN and 8 daN) and three levels of the sliding speed (0.26 m/s, 0.50 m/s and 1.00 m/s), in conditions with and without lubrication. By these tribological investigations the optimum quantity and size of the Al2O3 particles were established for obtaining the best characteristics form the aspect of wear, under the tested conditions. In all the test cases investigated composite materials possess significantly higher wear resistance than the pure metal substrate - the ZA-27 alloy.