Wear Behavior of Plasma-Sprayed Al-12Si/SiC Composite Coatings under Dry and Water-Lubricated Sliding

Abstract

Powders of Al-12Si with 25 and 50wt% SiC particles were ball-milled in a conventional rotating ball mill with alumina balls for 2h. The milled powders were plasma-sprayed onto aluminum and stainless steel substrates to obtain Al matrix composites with high SiC weight fraction. The microstructure characteristics of the sprayed composites were investigated by metal microscopy. Surface roughness, coating thickness and microhardness were measured. Microhardness values increased when the amount of SiC particles in Al-12Si coatings increased. The wear behavior of the coatings under dry-sliding and water-lubricated sliding with stainless steel counter material was studied using ball on disc for 10kN. Wear surfaces were investigated with scanning electron microscopy (SEM). Increasing SiC content of coatings increased the wear resistance. The highest wear resistance in coatings was observed in the coating having 50% SiC.