S32750超级双相不锈钢TIG自熔焊接接头组织及力学性能  

Microstructure and mechanical properties of S32750 super duplex stainless steel welded joint by TIG

作　　者：柳阳 李国平[1,2] 王立新[1,2] 赵振铎[1,2] 范光伟[1,2] Liu Yang;Li Guoping;Wang Lixin;Zhao Zhenduo;Fan Guangwei(Taiyuan Iron&Steel(Group)Co.,Ltd.,State Key Laboratory of Advanced Stainless Steel Materials,Taiyuan 030003,China;Shanxi Taiyuan Stainless Steel Co.,Ltd.,Taiyuan 030003,China)

机构地区：[1]太原钢铁(集团)有限公司,先进不锈钢材料国家重点实验室,太原030003 [2]山西太钢不锈钢股份有限公司,太原030003

出　　处：《焊接》2020年第6期18-22,62,共6页Welding & Joining

基　　金：国家重点研发计划(2016YFB0300201);中国科协青年人才托举工程(2018QNRC001);山西省自然科学基金(201801D121076);山西省科技重大专项(20181101015)。

摘　　要：对S32750超级双相不锈钢薄板进行了5个热输入条件下的TIG自熔焊接试验,采用光学显微镜、激光共聚焦显微镜和扫描电子显微镜对焊接接头的显微组织进行了观察与分析,并检测了焊缝的N含量及焊接接头的力学性能。结果表明,在焊缝金属中,随着热输入的增加,晶界处和晶粒内部的奥氏体均变粗变大,铁素体含量呈线性下降。不同热输入下的焊接接头硬度均高于母材,但热输入大的焊接接头拉伸性能低于母材。S32750 super duplex stainless steel plates were welded by TIG under five different heat input.Microstructures of welded joints were carefully observed by means of optical microscope,laser confocal microscopy and scanning electron microscopy.N content of the weld and mechanical properties of welded joints were tested and analyzed in detail.The results showed that with the increase of heat input,the grain size of austenite in grain and on grain boundary increased gradually in the weld metal,while the ferrite content decreases linearly.The microhardness of welded joints under different heat input were higher than that of base metal.Nevertheless,the tensile strength under higher heat input was lower than that of base metal.

关 键 词：超级双相不锈钢 钨极氩弧焊 热输入 

分 类 号：TG444[金属学及工艺—焊接]