Friction characteristics in press forming of 5000 series aluminum alloy sheet

Abstract

Demand of press forming of aluminum alloy sheet is increasing for improvement of fuel efficiency. FEM analysis of press forming is required to be more accurate. The objective of this study is to clarify the effect of friction coefficient on analytical accuracy in press forming FEM analysis. Spherical forming experiment and FEM analysis were performed to measure the contact pressure and sliding speed of the blank against the punch. Sliding friction test was performed to measure the friction coefficient with low pressure and low speed. The measured friction coefficient was input to the commercial FEM analysis soft PAM-STAMP2G as varied friction coefficient. The experimental thickness strain distributions were compared with the calculated results. FEM analysis results using varied friction coefficient had a better accuracy than those using constant friction coefficient.