A Multi-Scale Approach for Predicting Wrinkling and its Experimental Validation

Northwestern University, Evanston IL

Investigators

Abstract

This research project aims to provide experimental data on material resistance to wrinkling under various loading conditions and to provide a reliable and robust tool for simulating wrinkling in sheet metal forming processes, which will dramatically increase the confidence level on simulation results and therefore, be extremely beneficial to product and process development. The increasing environmental concerns and global competition have pressured the auto industry to aggressively search for thinner, lighter and stronger materials. As the thickness of sheet metal decreases, the tendency towards wrinkling increases significantly. It is therefore essential to have a good understanding of the onset of wrinkling and its post-buckling behavior of sheet metal so that the development time of bringing these new materials to final goods can be minimized. The experiments will include a newly developed wedge test, a shrink flanging test and forming of an irregular three-dimensional shape. The test results will be used to verify the computability of a new simulation tool, finite element methods with meshfree-enrichment (FEMME), which is believed to be able to capture local deformation effectively without the need of remeshing. The methodology and associated software routines will be posted on our website for easy public access.