Electrical discharge machining of cast metal matrix composites

摘要: Abstract Metal Matrix composites (MMCs) are well-known for their superior mechanical properties over those of unreinforced alloys. A full scale application such advanced materials however is hindered by the high cost machining. Unacceptable short tool life and resulted sub-surface damage MMCs major issues when machined conventional machining processes. This paper investigates feasibility applying electrical discharge (EDM) process cast aluminum reinforced with silicon carbide particles (SiCp). Statistical models were developed to predict effect parameters on metal removal rate, re-cast layer, surface finish. It was found that SiC shield protect matrix from being vaporized, thus reduce rate. The un-melted drop out MMC together surrounding molten droplets. While some droplets flushed away dielectric, others trap loosened then re-solidify onto form a layer (RCL). No crack in RCL softened heat-affected zone (HAZ), which below RCL. input power controls rate depth, but current alone dominates finish an EDM'ed surface.