核级高硅含钛不锈钢激光-电弧复合焊接工艺及接头组织性能  

Laser-Arc Hybrid Welding Process and Joint Microstructure and Properties of Nuclear Grade High Silicon Titanium-containing Stainless Steel

作　　者：张正浩 王传强 齐恩语 李云龙 吴世凯[1,2,3] Zhang Zhenghao;Wang Chuanqiang;Qi Enyu;Li Yunlong;Wu Shikai(Department of Materials and Manufacturing,Beijing University of Technology,Beijing 100124,China;Nanjing Zhongke Raycham Laser Technology Co.,LTD.,Nanjing,Jiangsu 210038,China;Shanghai Institute of Optics and Fine Mechanics,China Academy of Science,Shanghai 201800,China)

机构地区：[1]北京工业大学材料与制造学部,北京100124 [2]南京中科煜宸激光技术有限公司,江苏南京210038 [3]中国科学院上海光学精密机械研究所,上海201800

出　　处：《中国激光》2021年第14期75-85,共11页Chinese Journal of Lasers

摘　　要：采用激光-氩弧电弧复合焊接方法对核级高硅含钛奥氏体不锈钢的包壳材料进行对接焊接,通过正交试验研究焊接工艺参数对焊缝气孔率的影响,并对焊缝的显微组织及接头的力学性能进行分析。试验结果表明,提高焊速和离焦量可以明显降低气孔的数量和尺寸,在优化的焊接工艺参数条件下可以获得成形良好和无气孔缺陷的焊缝;焊缝区组织为单一奥氏体相,焊缝区中心为粗大的柱状晶,熔合线附近焊缝区的晶粒尺寸减小,并存在细小的胞状晶和等轴晶;热影响区组织与母材基本相同,但其晶粒尺寸略大于母材;焊接接头的平均抗拉强度为607 MPa,约为母材抗拉强度的73%,平均断后延伸率为6.5%;拉伸断口处存在大量的撕裂棱和韧窝,其为典型的韧性断裂;焊缝区域的硬度在160 HV_(0.1)左右,约为母材硬度的60%;180°的面弯和背弯结果合格,接头性能满足核反应堆中核燃料组件对包壳材料的技术要求。Objective High silicon titanium-containing austenitic stainless steel is used as shell material in nuclear reactor fuel components due to its excellent radiation resistance and high-temperature mechanical properties.By adjusting element content based on 316 stainless steel,1515 stainless steel improved service performance and became the third-generation shell material of the fast neutron reactor fuel component.Welding is an essential method for building shell components during manufacturing.For the welding of 1515 stainless steel,the traditional arc welding method is prone to defects,such as thermal cracks,intergranular corrosion,and joint embrittlement,and porosity defects of laser-welding lead to failure risks during service conditions,especially for incomplete penetration jointing.Thus,decreasing welding defects of shell components and obtaining welding joints,which meet technical requirements,are the main task for the welding of 1515 stainless steel.In this study,shell components are welded using the laser-arc hybrid welding method.By process optimized,welded joints without pores,cracks,and other defects,and mechanical properties met technical requirements of a nuclear reactor.Methods In this study,1515 stainless steel with backing plate is welded using the laser-arc hybrid welding method.First,the welding orthogonal test is designed based on the preliminary process exploration,and optimized welding parameters are obtained.The quantity and distribution of pores in welded joint are detected by radiographic testing(RT)ray detection and the influence of laser power;welding speed and defocus on the porosity of the weld joint are investigated.Second,the microstructure of the welded joint is observed using the optical microscope and mechanical properties of tensile.Besides,bending and hardness are tested.Finally,the tensile fracture section is observed through a scanning electron microscope.Results and Discussions Welding speed and defocus have a strong influence on the porosity of the welded joint.Increasing weldi

关 键 词：激光制造 材料 激光-氩弧复合焊接 高硅含钛奥氏体不锈钢 显微组织 力学性能 

分 类 号：TG456.7[金属学及工艺—焊接]