An investigation on electrical discharge metal matrix coating of ZE41A magnesium alloy

The present paper studied the experimental investigation on electrical discharge coating of ZE41A magnesium alloy (EDC) with tungsten carbide-copper (WC/Cu) powder metallurgy (PM) electrode. In order to attain the surface characteristics, three parameters were selected such as compaction load, current and pulse on time. Response characteristics such as material transfer rate (MTR) and surface roughness (Ra) were considered in this study. Central composite design in response surface methodology was applied to conduct experiments. Empirical models were developed for MTR and SR. AVOVA test was conducted to identify the most influence parameters. Additionally, optimized parameters were identified by response surface optimizer. It is observed that the current play a vital role in increasing the MTR and minimize the SR of the coated surface followed by compaction load and pulse on time. Various studies such as scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) were carried out on the coated surface. Bulk mass deposition and bigger craters were observed in the surface coated with 150 MPa and 3A respectively.