Taguchi Approach for Parametric Study in Plasma Arc Machining of SS-410

The plasma cutting process is investigated experimentally in the present work for cutting of SS 410 material. The quality of cut has been monitored by measuring the kerf width, bevel angle, straightness and width of HAZ. Since, there are several possible machine settings (i.e., current, pressure, cutting speed, torch height, etc.), parts cut by using the plasma cutting process often lack good quality. Sometimes, these parts are not completely cut because the plasma gas does not penetrate all the way through the sheet metal due to insufficient pressure or excessive torch height, pressure, cutting speed or current. This research was conducted to discover the optimum machine settings by implementing a Design of Experiments approach (DOE) to find those relevant factors that affect the part’s surface quality characteristics (i.e., surface roughness, kerf width, accumulation underneath the work piece, bevel angles, and dimensional accuracy of the metal work piece and analyzing the results by Taguchi Method. These important characteristics of part quality were considered as response variables. Final results identified an optimal machine configuration that facilitates the fabrication of parts with close-to-perfect quality for all 9 quality measurement responses.