δ-相变诱发塑性（TRIP）钢具有高的强韧性，可达到第三代汽车钢性能要求，且可电阻点焊，是一种新型的具有较高产业化前景的先进汽车钢。主要阐述了δ-TRIP钢的发展、组织与性能、相变与组织演化机理、强韧性机理、电阻点焊工艺与物理冶金机理。

δ- transformation induced plasticity（TRIP） steel has performed high strength combined with excellent ductility，which satisfy the requirements for the third generation advance steels for automotive application. In addition，it could to be spot welded. It’s high potential to be industrialized for both manufacture and automotive application. The development of δ-TRIP，microstructure and mechanical properties，transformation and microstructure evolution，strength and toughness mechanism will be reviewed. The process and physical metallurgy for resistance spot welding will be discussed as well.