Electroless-plating of Ag nanoparticles on Al2O3 for enhanced mechanical and wear properties of Cu–Al2O3 nanocomposites

Abstract

Wettability between Cu and Al2O3 nanoparticles is relatively low, which limit the applicability of this nanocomposite. To this end, electro-less deposition of Ag over Al2O3 nanoparticles were applied to improve their wettability with Cu matrix. Al2O3 coated Ag were mixed with commercially pure Cu powder in varying weight percentages (0, 2, 4, 6 and 8) and then nanocomposites were synthesized through powder metallurgy route. To obtain uniform distribution of nanoparticles in Cu matrix, mixing was carried out via mechanical alloying. Microstructure, mechanical and wear behaviors were investigated to see the effect of Al2O3 nanoparticles content in Cu. The result showed that Al2O3 nanoparticles are homogenously dispersed in the Cu matrix. The hardness and compressive strength were improved by the addition of nanoparticles up to 8wt%. Around 30% improvement was found in the strength of the nanocomposite. Furthermore, the average hardness of the composite coatings varies from 65.2 to 150 HV as Al2O3 content increases from 0 to 8wt%. Abrasive wear analysis showed that the abrasive wear resistance of the nanocomposites improves with the increment of nanoparticle content. The microstructure refines due to Al2O3 addendums illustrated a considerable function in the wear behavior of the Cu matrix.