Experimental and finite element studies of single stage incremental forming process: effect of process parameters on maximum wall angle and thickness distribution

Abstract

The main objective of this study is to investigate the effect of process parameters on maximum formable wall angle in incremental forming of 0.5 mm thickness extra deep drawing steel sheets. For this purpose, four important process parameters namely, tool diameter (A), feed rate (B), part geometry (C) and step depth (D) have been correlated with maximum wall angle. Experiments have been conducted on CNC milling machine in accordance with Taguchi L9 orthogonal array. The statistical methods, signal to noise (S/N) ratio and Pareto ANOVA have been used to find out the optimum process settings and percentage of contribution of different process parameters on maximum wall angle. A linear regression model was also proposed to predict the wall angle as a function of process parameters. Based on the studies, the optimum conditions were found to be A1B2C1D1 (A = 6 mm, B = 1500 mm/min, C = VWACF, and D = 0.7 mm). It was also found that the tool diameter has significant effect on maximum wall angle followed by feed rate, shape and step depth. Furthermore, wall thickness distribution of formed parts under different process conditions has been studied through experiments and finite element simulations using LS-DYNA. A good correlation was found between experimental results and numerical simulations.