钢筋预埋件连续驱动摩擦焊接头组织及性能  

Microstructure and Mechanical Properties of T-joint of Embedded Parts by Continuous Drive Friction Welding

作　　者：章中华 曾凡勇 肖志威 谢利平 薛雅旭 朱称生 ZHANG Zhonghua;ZENG Fanyong;XIAO Zhiwei;XIE Liping;XUE Yaxu;ZHU Chengsheng(China Nuclear Industry 22nd Construction Co.,Ltd.,Wuhan 430051,China)

机构地区：[1]中国核工业第二二建设有限公司,湖北武汉430051

出　　处：《电焊机》2023年第1期91-99,共9页Electric Welding Machine

摘　　要：针对核电典型钢筋预埋件手工焊接存在效率低、工作强度大等问题,提出采用连续驱动摩擦焊接方式进行焊接,并对接头的宏观形貌、微观组织和力学性能进行了分析。结果表明:预埋件摩擦焊T形接头因焊接过程散热不均,上部飞边与下部飞边呈不对称分布,钢筋侧金属在焊接过程中发生了明显的流变。通过高倍金相观察和扫描分析,证实了焊缝界面处的“黑线”特征为正常组织而非焊接缺陷;接头焊核区组织发生了动态再结晶,为细小的铁素体+贝氏体,热影响区组织中的碳化物受热作用开始析出。顶锻量可作为衡量接头拉伸质量的参数,当钢筋顶锻量超过19 mm后,接头拉伸合格率可达100%;通过小尺寸拉伸和硬度测试发现,接头最薄弱的区域为母材,影响T形接头断裂位置的指标为焊合率,而焊合率与焊接参数(顶锻量)、焊前清理有关。Continuous drive friction welding method was used for typical embedded steel bars in nuclear power plant,and the macroscopic morphology,microstructure and mechanical properties were analyzed.The results show that the upper and lower flying edges of the T-shaped friction welding joint are asymmetrically distributed due to the uneven heat dissipation during welding process,and the metal of the reinforcement side has obvious strain deformation during welding process.Through high magnification metallographic observation and scanning analysis,it is confirmed that the"black line"at the weld interface is normal metal organization rather than welding defect.Dynamic recrystallization occurrs in the weld nugget zone,which is fine ferrite and bainite,and carbides in the microstructure of the heat affected zone begin to precipitate after heating.The upset forging quantity can be used to measure the tensile quality of the joint.When the upset forging quantity of reinforcement exceeds a certain value,the tensile qualification rate of the joint can reach 100%.Through small-size tensile and hardness tests,it is found that the weakest area of friction weld joint is steel base metal,and the index affecting the fracture position of T-joint is seaming ratio,which is related to welding parameters(upset forging quantity)and pre-welding cleaning.

关 键 词：钢筋预埋件 T形接头 连续驱动摩擦焊 飞边 显微组织 

分 类 号：TG453.9[金属学及工艺—焊接]