Delamination behavior analysis of steel/polymer/steel high-strength laminated sheets in a V-die bending test

Abstract

Steel/polymer/steel laminated sheets were fabricated by inserting three types of adhesive layers between two 590-MPa grade high-strength steel sheets. V-die bending tests of the laminated sheets were conducted and the results showed that the delamination behaviors depended on the inserted adhesive type. To investigate the mechanical behaviors of the adhesive layers, delamination tests for each adhesive layer along normal and shear directions were performed. Based on the results of the delamination tests, an inverse parameter characterization using an iterative finite element simulation with interface elements was successfully conducted to characterize the cohesive properties for mixed-mode bilinear cohesive zone model that clearly described the measured load–displacement curves. The results of the V-die bending tests were predicted through simulations using the characterized cohesive properties; the delamination patterns, punch force drop, and entire level of punch force agreed well with the experimental results. Delamination mechanisms were deduced based on parametric studies conducted to elucidate the direct effect of cohesive properties on delamination.