Wrinkle Generation Process in Press Forming of High-strength Steel Sheet

Abstract

The wrinkle generation process of high-strength steel sheets in compression is investigated by finite element method (FEM) simulation and experiment. When a high-strength steel sheet is compressed under a pad with a constant load and initial clearance, there exist two modes in the wrinkle generation process. One is the wrinkle growth mode with the progress of compression upon lifting the pad. The other is the wrinkle disappearance mode, where the wrinkle generated at the early stage of the compression process vanishes with the decrease in clearance between the pad and the sheet resulting from the increase in sheet thickness. The wrinkle disappearance mode is applicable when the pad load is higher than the initial peak value of the wrinkle pushing force in compression.