Study of TiC Coating on different type Steel by Electro Discharge Coating

Abstract

Electro discharge coating process is non-conventional surface modification process, where hard material can be deposited on the metal substrate using reverse polarity of EDM. In this work, TiC coating deposited on different type of steel substrate i.e. AISI 1020 Mild steel, AISI 304 Stainless steel and M42 type HSS tool steel using powder metallurgy (P/M) compacted tool electrode prepared with TiC and Cu (60:40 wt%). Effect of peak current on deposition rate of coating for different type of steel has been investigated. Deposition rate is higher in case of AISI 304 stainless steel than the AISI 1020 mild steel and M42 HSS tool steel substrates. This is due to the difference in thermos-mechanical properties of the steel substrates which also have the significant effect on the microstructure of the coating produced by EDC process. Detailed micro structural study of the coating has been performed through SEM and EDS analysis. A comparative study of the characteristic of the coating produced on different steel has also been analyzed. With the view to improve the process a setup for EDC by powder suspension method was designed and fabricated. An attempt has been made to deposit (TiC+TiB2) coating on mild steel by powder suspension method by mixing Ti and B4C powder in kerosene dielectric