Strength and ductility enhancement in the gradient structured twinning-induced plasticity steel by ultrasonic nanocrystalline surface modification

In this study, microstructural evolution and mechanical properties of the ultrasonic nanocrystalline surface modification (UNSM) processed twinning-induced plasticity (TWIP) steels were investigated. As a result, UNSM TWIP steel achieves high strength and large elongation. Moreover, the strength-ductility combination of the UNSM TWIP improves as the applied impact force increases.