哈氏合金C-22焊接接头性能研究及微观组织分析  

Study on the properties of Hastelloy C-22 alloy welded joints and microstructure analysis

作　　者：张艺潇 张巨银 王学平 ZHANG Yixiao;ZHANG Juyin;WANG Xueping(Gansu Province Special Equipment Inspection and Testing Institute,Lanzhou 730050,China)

机构地区：[1]甘肃省特种设备检验检测研究院,兰州730050

出　　处：《压力容器》2024年第5期43-49,共7页Pressure Vessel Technology

摘　　要：为了探究哈氏合金C-22(Hastelloy C-22合金)的焊接性能,采用钨极氩弧焊(GTAW)和焊条电弧焊(SMAW)分别对Hastelloy C-22合金进行了焊接试验,从力学性能、耐腐蚀性能及微观组织等方面进行了研究分析。结果表明,采用这两种焊接方法施焊的焊缝表面成型良好,无裂纹、气孔、夹杂等缺陷。因熔池凝固速率和温度梯度的差异导致焊接接头各区域晶粒大小不一致,晶粒形态也存在差异,因此,显微硬度从焊缝到母材出现逐渐减小的趋势。两种焊接方法焊接接头在弯曲载荷的作用下均无裂纹等缺陷出现,试验结果均合格。GTAW接头晶粒略小于SMAW接头,这也使得GTAW对接接头力学性能和耐腐蚀性能均要优于后者。GTAW接头平均抗拉强度可达到799 MPa,略高于母材,平均腐蚀率仅为0.299 mm/a,比母材降低18.31%。该研究为强腐蚀介质压力容器的生产制造提供了参考。Welding tests were carried out on Hastelloy C-22 alloy using tungsten argon arc welding(GTAW)and electrode arc welding(SMAW),respectively,and the various regions of the welded joints were studied and analyzed in terms of mechanical properties,corrosion resistance and microstructure.The results show that the surface of the weld applied by these two welding methods is well formed and free of cracks,blowholes,inclusions and other defects.Due to the differences in the solidification rate of the molten pool and the temperature gradient,the grain sizes are not uniform in all regions of the welded joint,and there are differences in the grain morphology,so the microhardness tends to decrease from the weld to the base metal.There are no cracks and other defects in the welded joints welded by both welding methods under the bending load,and the test results are qualified.Tungsten argon arc welded joints grain is slightly smaller than that of the electrode arc welded joints,which also makes the mechanical properties and corrosion resistance of the GTAW butt joints are better than the latter.The average tensile strength of GTAW welded joints can reach 799 MPa,which is slightly higher than that of the base metal,and the average corrosion rate is only 0.299 mm/a,which is 18.31%lower than that of the base metal.This study provides a reference for manufacturing of the pressure vessels for strong corrosive media.

关 键 词：哈氏合金 焊接接头 微观组织 力学性能 耐腐蚀 

分 类 号：TH142.2[一般工业技术—材料科学与工程] TG113.26[机械工程—机械制造及自动化]