Investigation on the electrically-assisted stress relaxation of AZ31B magnesium alloy sheet

In this paper, the influence of the electrical parameters on spingback reduction during electrically-assiated sheet V-bending process was investigated. At first, electrically-assisted stress relaxation tests were carried out and the stress relaxation model considering the electric pulses was proposed and validated. In the stress relaxation tests with and without electric pulses at the same temperature, the athermal effect was observed. Based on the stress relaxation model and Mises yield criterion, the spingback angle prediction model was proposed and then verified by the V-bending experimental data. Microstructure analysis shows that detwinning occurs in the electrically-assisted stress relaxation after V-bending, which contributes to spingback reduction.