摘要
为提高20Cr2Ni4A-20 g异种钢中厚板的焊接效率,采用5 kW Slab CO2激光器对20Cr2Ni4A合金渗碳钢与20 g锅炉钢进行异种钢激光深熔焊工艺研究。研究了离焦量、保护气体配比、激光功率和焊接速度对焊缝形貌的影响。采用材料试验机对异种钢激光焊接焊缝拉伸性能进行了测试,采用扫描电子显微镜对断口微观形貌进行了表征。研究发现通过调节离焦量、同轴保护气体成分、激光功率和焊接速度可以优化焊缝成形,最终获得了厚度为8 mm的20Cr2Ni4A-20 g异种钢CO2激光焊接的最佳工艺参数为:离焦量为+2 mm,激光功率为5 kW,焊接速度为2.5 m/min,保护气体采用由5 L/min He与20 L/min Ar组成的混合气体,在此工艺参数条件下,激光焊接接头的抗拉强度高于20 g母材,母材为韧性断裂,断口呈典型的韧窝形态。
The deep penetration laser welding of 20Cr2Ni4A-20 g dissimilar steel is studied to increase the welding efficiency.The effects of laser welding parameters on the morphology of welding seam are investigated using 5 kW Slab CO2 laser.The tensile strength is tested by material testing machine,and the fracture morphologies are observed by scanning electron microscopy.The results show that the welding joint can be optimized by adjusting the defocusing distance,coaxial shielding gas flow rate,laser power and welding speed.The optimum process parameters of 8 mm thickness of 20 g and 20Cr2Ni4A dissimilar steel are： a laser power of 5 kW,a welding speed of 2.5 m/min,a shielding gas of 5 L/min He and 20 L/min Ar and a focusing distance of ＋2 mm.Under the optimum process parameters,the tensile strength of the welded joint is better than 20 g matrix,which is ductile fracture and the fracture presents dimple.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2011年第6期140-147,共8页
Chinese Journal of Lasers
关键词
激光技术
激光焊接
异种钢
深熔焊
工艺参数
拉伸强度
laser technique
laser welding
dissimilar steel
penetration welding
welding parameters
tensile strength
作者简介
作者简介：石岩（1972-），男，工学博士，副教授，主要从事激光加工技术方面的研究。E-mail：shiyan@cust．edu．cn
