【摘要】 舰船结构在承受爆炸冲击载荷时，焊接接头是薄弱环节。论文以Q355船用钢为对象，研究两种焊接方法下8和10 mm厚度的对接接头以及T型接头的拉伸冲击性能，设计了接头拉伸冲击试验装置，并提出临界冲击高度概念。试验结果表明，对接接头的焊接区域不是结构薄弱环节。计算了采用两种焊接方法制备的T型接头冲击断裂能量，采用激光-电弧复合焊参数制备的接头拉伸冲击性能弱于熔化极气体保护焊制备接头。微观分析表明，热影响区域粗晶区晶粒尺寸过大是激光-电弧复合焊接头拉伸冲击性能变差的关键因素。论文的研究方法和结果为接头冲击性能的提升提供了参考。更多还原

【Abstract】 When military ships are subjected to explosive load, welding joints are weak links in the structure. Taking the ship steel Q355 as the research object, tensile and impact properties of the butt joints with thicknesses of 8mm and 10mm and T-type joints with thicknesses of 8mm and 10mm were studied by using two welding methods, and the concept of critical impact height is presented. Test results show that the butt joint is not a weak link in the welding region. The impact fracture energy of the T-joint using two welding methods is calculated.The results show that the tensile and impact properties of T-joints prepared by laser-arc hybrid welding or melting electrode gas metal arc welding are poor, and the large grain size of coarse grain in the heat-affected zone is the key factor that affects the poor tensile impact properties. The research methods and results provide a reference for improving the impact performance of the joint.更多还原