Parameter design in plasma arc cutting of galvanised iron sheet using desirability function-based response surface methodology

Plasma arc cutting (PAC) is a widely used industrial process for cutting different materials at higher speeds. The capability of PAC to compete with laser cutting has created a significant amount of research attention. The present study was focused towards assessing the quality of cut obtained under different cutting conditions by varying the process parameters like cutting speed, arc current and stand-off distance. The quality of cut was monitored by measuring the surface roughness and kerf width. A new integrated approach of desirability function-based response surface methodology (DRSM) was disclosed for modelling and predicting the optimal cutting condition. The effectiveness of DRSM technique was proved by conducting a confirmation test. A significant improvement was observed in the quality characteristics and an overall P-profile plot of the cut surfaces was also examined to study the enhancement in surface finish. [Received 20 August 2014; Revised 15 April 2015; Accepted 25 April 2015]