中文摘要：

用点焊焊接工艺对1．8mm厚的高强度TRIP800钢板进行焊接，对接头进行了剪切试验，分析了焊接接头的硬度分布、显微组织及断口形貌。结果表明：试验工艺下点焊接头内基本不存在明显的缺陷，接头具有良好的剪切性能；接头熔合区为板条状马氏体组织，热影响区为马氏体、铁素体及贝氏体高温回火组织；剪切断口显现出韧性断裂特点。

英文摘要：

High-strengthed TRIP800 steel plates of 1. 8 mm thickness were spot welded, and then shear testing was performed on joint, and hardness distribution, microstructure and fracture morphology were analysed. The results show that there were not obvious defects in welded joint under testing process conditions, and the joint owned good shear property. The microstructure of joint fusion zone was strip martensite, and the microstrueture of joint heat affected zone were martensite, ferrite and high-remperature tempered banitte, The shear fracture showed ductile tear characteristics.