Comparison Research for Spring Backs of Dual-Phase Steels with Three Different Strength Grades

The spring backs of dual-phase steels with three different strength grades were investigated. The mechanical properties were measured, microstructures were observed, spring backs of L type and V type bending samples were measured. The influence of yield strength, flow stress, tensile strength on the spring back of dual-phase steels is analyzed. The results show that the spring back angles of L type samples increase with increasing strength of dual-phase steel. The spring back angles of V type samples increase with increasing bending angles and strength. The relation test results are of reference for prediction and compensation of spring back. The causes of complex spring back for V-type bending samples of three are analyzed.