Predicted Edge Crack Model of Hot Rolling for AZ31 Magnesium Alloy

Based on an equal pressure method, isothermal compression tests of AZ31 magnesium alloy at different strain rates of 0.005-5 similar to 3. s(-1) and different deformation temperatures of 473 similar to 673 K were performed by Gleeble-1500 simulator. The influences of deformation temperature and strain rate on the flow stress and critical fracture strain were investigated, and a basic model of critical fracture strain of AZ31 was established. Then the predicted edge cracking model of hot rolling for AZ31 was obtained based on the basic principles of magnesium alloy rolling edge cracking and fracture criterion of Cockcroft & Latham, which contains the material deformation activation energy and the technology parameters of rolling. In order to verify the correctness of the predicted edge cracking model, the corresponding relationship was achieved between damage value and edge crack depth along the width direction by the finite element simulation and rolling experiments in the same conditions. The results show that the average error is 11.3% between predicted values and measured values.