Investigation the Effect of Process Variables on the Formability of Parts Processed by Single Point Incremental Forming

Abstract

Incremental sheet metal forming process is an advanced flexible manufacturing process to produce various 3D products without using dedicated tool as in conventional metal forming. There are a lot of process parameters that have effect on this process, studying the effect of some parameters on the strain distributions of the product over the length of deformation is the aim of this study. In order to achieve this goal, three factors (tool forming shape, feed rate and incremental step size) are examined depending on three levels on the strain distributions over the wall of the product. Strain measurement was accomplished by using image processing technique using MATALB program. The significance of the control factors are explored using two statistical methods: analysis of variance (ANOVA) and main effect plot (MEP). All experiments were carried out on a sheet of Aluminum alloy (Al1050) with thickness 0.9 mm by using 3 axes CNC machine to produce frustum pyramid product. The result showed that the feed rate is a parameter that has large effect on the values of the effective strain percentage contribution of (42.86% and 51.42%), respectively, and is followed by step size (25.1% and 30.60%) percentage contributions and finally the tool shape with (21.79% and 10.54%) on the (55° and 45°) wall angle, respectively. The maximum and minimum average effective strain computed on the 55◦ forming angle were (0.580 and 0.399), respectively. Finally, the maximum and minimum average effective strain computed on the 45◦ forming angle were equal to (0.412 and 0.324), respectively.