S M Sivagami, N Murugan, A Elango, S Suresh Kumar
Weld hardfacing is mainly employed for improving wear, corrosion and heat resistant properties under high pressure and high temperature condition. The service life of the hardfaced component is increased by achieving the desired surface hardness which is identification to get the abrasive wear resistance. The macrohardness is generally influenced by welding process parameters such as welding current, welding speed, powder feed rate, plasma gas flow rate and oscillation frequency. Therefore, it is essential to develop mathematical models for the selection of appropriate welding process parameters that can predict the desired weld macrohardness. This paper mainly focuses the development of mathematical models using five factor, five level factorial technique to predict macrohardness in hardfaced gate valve. Analysis of variance was used to check the adequacy of the developed models. Also the empirical models developed were checked by conducting confirmation experiments. The effects of welding process parameters on the macrohardness are presented as graphs.