Influence of rubber pad on springback of titanium sheets by wipe bending process

In the wipe bending process, after the bending load or pressure is removed, the elastic strains remaining in the bend region cause a slight reduction in the bend angle. The term "spring back" refers to this reduction in bend angle, and it depends on many parameters like tool design, process conditions, and material parameters. In this work, simulations by Deform 2D software and experimental work were conducted to determine the effect of die radius, sheet thickness, and Silicone rubber pad thickness on spring back angle while bending Titanium Grade2 sheets. The results showed that die radius is the most important factor affecting the spring back angle in the wipe bending process. When the die radius increases, the spring back angle is also increased by (36%) and the second factor, when Silicon rubber pad thickness increases to (15) mm, decreases the spring back angle by (20.6%). The third factor is the Titanium thickness. When it increases (1) mm, the spring back is decreased by (12.4%). Also, surface roughness was improved when adding a Silicon Rubber pad in the range of (58.5% and 61%) for sheet thicknesses of 0.5 and 1mm, respectively. The results validate the same behavior for Titanium in a numerical and experimental model.