Affiliation:
1. Indian Institute of Technology, Guwahati, India
Abstract
In the present study, a high-velocity sheet metal forming experiment has been performed using a hemispherical end nylon striker inside the shock tube. The striker moves at a high velocity and impacts the sheet mounted at the end of the shock tube. Three different velocity conditions are attained during the experiment, and it helps to investigate the forming behavior of the material at different ranges of velocity conditions. Various forming parameters such as dome height, effective strain distribution, limiting strain, hardness, and grain structure distribution are analysed. The dome height of the material increases monotonically with the high velocity. The effective-strain also follows the similar variation and a bi-axial stretching phenomenon is observed. The comparative analysis with the quasi-static punch stretching process illustrates that the strain limit is increased by 40%-50% after the high-velocity forming. It is because of the inertial effect generated on the material during the high-velocity experiment, which stretches the sheet further without strain localization.