摘要
采用脉冲激光焊接器对0.2 mm厚的430不锈钢进行搭接焊工艺研究,对接头焊缝截面宏观形貌及微观组织进行观察分析,考察不同激光功率对接头焊缝力学性能的影响。结果表明,当焊接速度为10 mm/s、离焦量为0 mm、激光功率为130 W时两板实现熔透连接,焊缝表面成型较好,接头抗剪力达到2714 N。接头熔核区主要由粗大柱状晶的铁素体和少量马氏体组成,且垂直于熔合线指向焊缝中心生长。热影响区呈现上窄下宽形貌,由粗大等轴晶的铁素体和点状碳化物沉淀组成。焊缝熔宽和熔深都随着激光功率的增大而增大。焊接接头焊缝显微硬度呈“W”形状分布,热影响区出现明显的软化现象,较母材降低了36%。接头抗剪力随激光功率升高而增大,当母材实现完全熔透连接后,继续增加激光功率对接头的力学性能影响较小,拉伸试样断裂位置均发生在热影响区附近,表现为塑性断裂。
In this paper,the lap welding process of 0.2 mm thick 430 stainless steel is investigated by using a pulsed laser welder,The macroscopic morphology and microstructure of the joint weld cross-section were observed and analyzed,and the effects of different laser powers on the mechanical properties of the joint weld were investigated.The results show that when the welding speed is 10 mm/s,the defocus amount is 0 mm,and the laser power is 130 W,the two plates realize the fusion connection,the weld surface is well formed,and the joint tensile force reaches 2714 N.The joint molten core area is mainly composed of coarse columnar crystals of ferrite and a small amount of martensite,and it grows perpendicularly to the fusion line towards the center of the weld.The heat-affected zone is narrow at the top and wide at the bottom and consists of coarse equiaxial crystals of ferrite and nodular carbide precipitates.The weld width and depth increase with the increase of laser power.The microhardness of the welded joint is distributed in W type,and there was obvious softening in the heat-affected zone,which was 36%lower than that of the base material.Joint tensile strength increases with the laser power,when the base material achieves complete penetration of the joint,continuing to increase the laser power on the mechanical properties of the joint has little effect,the tensile specimen fracture location occurred in the heat-affected zone near the performance of plastic fracture.
作者
谢威亚
冯巧波
王春亮
聂宇
Xie Weiya;Feng Qiaobo;Wang Chunliang;Nie Yu(School of Energy and Mechanical Engineering,Shanghai University of Electric Power,Shanghai 200090,China;Shanghai Key Laboratory of Power Material Protection and New Materials,Shanghai University of Electric Power,Shanghai 200090,China)
出处
《应用激光》
CSCD
北大核心
2024年第9期37-45,共9页
Applied Laser
基金
国家自然科学基金面上项目(52175343)。
关键词
430铁素体不锈钢
脉冲激光焊
显微组织
力学性能
430 ferritic stainless steel
pulse laser welding
microstructure
mechanical property
