通过拉伸、弯曲、冲击和硬度试验以及光学显微镜和扫描电镜观察,研究了600MPa级钛微合金化高强钢焊接接头性能及焊缝和热影响区的组织、冲击断口形貌。结果表明,焊接接头具有较高强度及良好的弯曲塑性变形能力,焊缝组织为针状铁素体组织,冲击性能优异;热影响区组织为粗大贝氏体组织,冲击韧度有所降低,但其冲击断口形貌仍呈韧性断裂。 The tensile test, bending test, impact test, hardness test and optical microscopy and scanning electron microscopy (SEM) were used to study the microstructure and impact fracture morphology of 600MPa titanium microalloyed high strength steel welded joint and the weld and heat affected zone. The results show that the weld joint has high strength and good plastic deformation capacity. The weld microstructure is acicular ferrite structure with excellent impact performance. The HAZ has a coarse bainite structure with reduced impact toughness, However, the impact fracture appearance is still ductile fracture.