脉冲放电对焊接接头的强化分析

对含有裂纹的16Mn焊接接头脉冲放电后的拉伸过程进行了数值模拟,分析了脉冲放电强化对裂纹前缘应力状态的影响.数值分析表明,经脉冲放电强化后,焊接接头受拉时裂纹前缘处的应力集中降低,抗拉性能得到了提高;对含有裂纹的16Mn焊接接头试件进行脉冲放电和拉伸性能试验.结果表明,通过脉冲放电强化,裂纹前缘钝化并产生了硬而韧的白亮层组织,试件的断口变得均匀、拉伸性能平均提高了17.8%.数值模拟和试验证实了电磁热止裂技术对降低焊接接头应力集中、提高其抗拉性能的有效性.

Analysis of impacting on pulse current discharge for welded joint's strength

The numerical simulation of tensile process is obtained after pulse current discharge for 16Mn welded joint with crack. The impact on pulse current discharge for the crack edge''s stress is analyzed. The obtained results show that via pulse current discharge the stress concentration at the edge of crack decreases when tension pressure acts on the welded joint, but its tension property is improved. The experiment about pulse discharge and tensile properties for 16Mn welded joint with crack is done. It proves that by the way of pulse current discharge the edge of crack is bluntly, meanwhile specimen produces the structure of white layer which is hard and tough, homogeneous fracture and the welded joint''s tensile property is improved by 17.8%. Both numerical simulation and experiment can confirm that electromagnetic and thermal arrest technique can reduce welded joint''s stress concentration ard improve its tensile intensity.