超高强度钢300M激光焊接接头的组织和力学性能  

Microstructure and Mechanical Properties of 300M Laser Welded Joints ofUltra-High Strength Steel

作　　者：徐伟[1,3] 王晓光 门正兴 Xu Wei;Wang Xiaoguang;Men Zhengxing(College of General Aiation,Chengdu Aeronautie Polytechnic,Chengdu,Sichuan 610100,China;College of Aeronautical Manufacturing Egineering,Nanchang Hatngkong University,Nanchang,Jiangxi 330063,China;The Iunouation Base of School-Enterprise Cooperatiom Aviation Electrouic Technology in Sichuan,Chegdu,Sichuaw 610100,China)

机构地区：[1]成都航空职业技术学院通用航空学院,四川成都610100 [2]南昌航空大学航空制造工程学院,江西南昌330063 [3]四川省高等学校校企联合“航空电子技术”应用技术创新基地,四川成都610100

出　　处：《激光与光电子学进展》2020年第15期149-154,共6页Laser & Optoelectronics Progress

基　　金：四川省科技厅科技计划项目(2019YJ0519);四川省教育厅自然科学重点项目(18ZA0032);成都航空职业技术学院2020年自然科研项目。

摘　　要：为了研究300M低合金超高强度钢激光焊接接头的组织和力学性能,采用光纤激光器对300M钢进行自熔焊对接试验,结合拉伸测试等分析方法研究了焊接接头的焊缝形貌、组织变化特征和力学性能,讨论了焊缝金属快速凝固过程中的相变。结果表明:300M低合金超高强度钢激光焊接接头的焊缝横截面呈典型的“Y”形;焊缝金属主要由柱状树枝晶组成;焊缝组织主要由马氏体以及残余奥氏体组成。靠近焊缝的热影响区分为硬化区和软化区,硬化区的硬度约为734HV,软化区的硬度约为456HV,接头的断裂位置为软化区,接头的抗拉强度为1269MPa,约为母材强度的65%。In order to study the microstructure and mechanical properties of laser welded joint of 300M low alloy ultra-high strength steel,fiber laser is used to perform the self-fusion welding butt test of 300M steel.The weld morphology,microstructure change,and mechanical properties of welded joints are studied by means of tensile test and other analytical methods.The rapid solidification process of weld metal is discussed.The results show that the weld cross-section of the laser welded joint of the 300M low alloy ultra-high strength steel has a typical"Y"shape.The weld is mainly composed of columnar dendrites,and the weld structure is mainly composed of martensite and retained austenite.The heat effect near the weld is divided into a hardened zone and a softened zone.The hardness of the hardened zone is about734HV,the hardness of the softened zone is about 456 HV,the fracture location of the joint is the softened zone,and the tensile strength of the joint is 1269 MPa,which is about the 65%of the strength of host material.

关 键 词：激光光学 300M超高强度钢 凝固路径 显微组织 力学性能 

分 类 号：TG14[一般工业技术—材料科学与工程]