【摘要】 面对日益严峻的环境问题，汽车工业应进一步减轻整车质量以实现节能减排的目标。传统质轻高强钢，如双相钢(DP)、相变诱发塑性钢(TRIP)和奥氏体钢等，因生产成本高、强塑积较低和冶金等问题限制了其应用。中锰TRIP钢强塑积可达30GPa%～60GPa%,实现了优异综合力学性能与质轻特点的良好结合，在车身轻量化方面具有极广的应用前景。本文从中锰TRIP钢微观组织演变规律与形变机理出发，探讨影响其电阻点焊接头质量的主要因素，概述了母材化学成分、微观结构、熔核几何尺寸和焊接工艺等方面对其质量的影响。通过分析焊接过程中奥氏体的马氏体相变、晶粒尺寸、形貌等特征，揭示了影响中锰TRIP钢焊点热影响区韧性的内在因素。综述了近年来先进高强钢(AHSS)的研究，阐述了AHSS三种典型焊点失效模式、失效内在机制与其影响因素，重点关注了焊点在拉剪试验中的断裂行为，提出了一种通过预测临界熔核尺寸以保证拔出失效(Pull-out failure, PF)的方法。最后，总结了焊后改性方面的最新研究，并展望了未来中锰TRIP钢电阻点焊的研究热点与方向。更多还原

【Abstract】 In response to increasingly severe environmental problems, the automotive industry should cut down the weight of vehicles to achieve energy-saving and emission-reduction goals. The application of traditional light-weight high-strength steels, such as dual-phase steel(DP), transformation-induced plasticity steel(TRIP), austenitic steel, etc., is limited by due to production costs, low plastic product and metallurgical issues. The strong plastic product of medium manganese TRIP steel can reach 30 GPa%—60 GPa%, which achieves a good combination of excellent comprehensive mechanical properties and lightweight characteristics, and has extremely high application prospects in lightening the body. Based on the evolution of microstructure and deformation mechanism of medium-Mn TRIP steel, the main factors on the quality of the resistance spot welding joint were discussed, and the effects of chemical composition, microstructure, nugget geometry and welding process of the base metal were summarized. By analyzing the characteristics of martensite transformation, grain size, and morphology of austenite during the welding process, the internal factors on the toughness of the heat-affected zone of the welded joint of the medium-Mn TRIP steel were revealed. This review summarized the research on advances of high strength steel(AHSS) in recent years, expounded the three typical failure modes of AHSS solder joints, the internal failure mechanism and its influencing factors, and focused on the fracture behavior of solder joints in tensile and shear tests. A method for predicting the critical nugget size to ensure pull-out failure(PF) was proposed. Finally, the latest research on post-welding modification was summarized, and future research hotspots and directions of resistance spot welding of medium-Mn TRIP steel were prospected.更多还原