Optimization of process parameters for micro-plasma arc welding-based rapid prototyping

A direct metal rapid prototyping process based on micro-plasma arc welding is presented. The impact of the ratio of width to height of the deposited track cross-section (R) on part quality is investigated. Taguchi method is adopted to analyze the effect of each process parameter on R, and the optimized process parameters are obtained. The results show that the quality of the parts with larger R is better than that with smaller R, and the pulse current, wire-feeding speed, scanning speed and plasma gas flow rate exert significant effects on R. The overlapped surface smoothness, tensile strength and elongation of the parts fabricated with the optimized parameters are measured to show the obviously better performances than those of the parts in the ordinary technological process.