钒合金激光焊焊接接头的组织及力学性能研究  

Microstructure and Mechanical Properties of Laser Welded Joint of Vanadium Alloy

作　　者：徐立群 姜少宁[1] 胡心平[1] 李殿超 XU Liqun;JIANG Shaoning;HU Xinping;LI Dianchao(School of Mechanical&Automotive Engineering,Qilu University of Technology,Ji'nan 250353,China)

机构地区：[1]齐鲁工业大学(山东省科学院)机械与汽车工程学院,山东济南250353

出　　处：《热加工工艺》2022年第5期23-26,31,共5页Hot Working Technology

基　　金：国家自然科学基金项目(51501097);山东省自然科学基金项目(ZR2014EMP005);校级大学生创新创业项目(xj201810431102)。

摘　　要：研究了激光焊用于连接ITER包层结构候选材料钒合金的可行性。当激光功率为2000 W,焊接速度为10mm/s,光斑直径为0.3 mm时可获得焊缝结合情况良好的钒合金焊接接头,并进行了组织形貌观察及力学性能测试。结果表明,钒合金的焊缝结合情况良好。焊缝的组织主要由焊缝中心细小的等轴晶区(尺寸约10μm)以及靠近熔合区粗大的柱状晶组成。焊缝与母材之间有明显的熔合线,由于焊缝区的碳、氧含量明显升高,出现了板条状Ti(CO)析出物。焊缝的硬度约750.6 HV,与母材相比,出现明显的硬化现象。焊接接头的拉伸强度低于母材,伸长率只有母材的1/5,断口出现在焊缝区。焊接过程中碳、氧等杂质元素含量的升高以及板条状Ti(CO)析出物的产生,使得钒合金室温拉伸性能降低。The feasibility of laser welding to connect the vanadium alloy candidate material of ITER cladding was investigated.When the laser power is 2000 W,the welding speed is 10 mm/s,the spot diameter is 0.3mm,the vanadium alloy welded joint with good bonding condition was obtained,and the structure observation and mechanical property test were carried out.The results show that the vanadium alloy is well welded.The microstructure of the weld is mainly composed of a fine equiaxed crystal area(size about 10μm)in the center of the weld and coarse columnar crystals near the fusion area.There is an obvious fusion line between the welding seam and the base metal.Because the carbon and oxygen contents in the welding seam area increase significantly,lath-like Ti(CO)precipitates appear.The hardness of the weld is about 750.6 HV,which is obviously hardened compared with the base metal.The strength of the welded joint is lower than that of the base material,the elongation is only 1/5 of the base material,and the fracture occurs in the weld zone.The increase of the content of impurity elements such as carbon and oxygen during the welding process and the generation of lath-like Ti(CO)precipitates reduce the room-temperature tensile properties of the vanadium alloy.

关 键 词：钒合金 激光焊 富Ti析出物 力学性能 ITER(国际热核聚变实验反应堆) 

分 类 号：TG456.7[金属学及工艺—焊接] TG146.413[一般工业技术—材料科学与工程]