ERW焊管焊缝组织性能研究  

Study on Microstructure and Properties of Weld Seam of ERW Welded Pipe

作　　者：田亚强 田耕 王远志 王彩芬 宋进英 郑小平 陈连生 TIAN Yaqiang;TIAN Geng;WANG Yuanzh;WANG Caifen;SONG Jinying;ZHENG Xiaoping;CHEN Liansheng(Key Laboratory of the Ministry of Education for Modem Metallurgy Technology,North China University of Science and Technology,Tangshan 063210,China;Han Dan City Zheng Da Steel Pipe Co.,Ltd.,Handan 056700,China;Hebei Welded Steel Tube Industrial Technology Research Institute,Handan 056700,China)

机构地区：[1]华北理工大学教育部现代冶金技术重点实验室,河北唐山063210 [2]邯郸市正大制管有限公司,河北邯郸056700 [3]河北省焊接钢管产业技术研究院,河北邯郸056700

出　　处：《热加工工艺》2019年第23期155-158,162,共5页Hot Working Technology

摘　　要：通过拉伸试验对ERW焊管进行力学性能分析,并采取OM、SEM、EDS等检测手段,对滚槽过程中焊缝开裂与未开裂的ERW焊管的焊缝特征进行了对比和分析,总结了影响ERW焊管焊缝组织性能的几点因素。结果表明:未开裂试样焊缝处组织组成为珠光体+铁素体,焊缝热影响区呈现标准"腰鼓形",金属流线清晰,流线上升角正常;开裂试样裂纹平直光滑,呈"V"形,属于脆性断裂,裂纹内部存在一定量氧化物夹杂,焊缝组织组成为珠光体+铁素体,焊缝热影响区较宽,金属流线不明显,由此推断造成焊缝断裂的原因是焊接过程中出现了"冷焊"。焊缝拉伸试验中,滚槽未开裂试样断裂位置在母材处,滚槽开裂试样断裂位置在焊缝处。焊接过程中的"冷焊",焊缝中的氧化物夹杂等都降低了焊缝的强度。The mechanical properties of the ERW welded pipe were analyzed by tensile test.OM,SEM and EDS were used to compare and analyze the weld characteristics of weld cracking and uncracked ERW welded pipes during grooving process.Several factors affecting the microstructure and properties of ERW welded pipe were summarized.The results show that the microstructure of the welds of the uncracked samples is pearlite+ferrite,and the heat affected zone of the weld shows standard"waist drum shape".The metal flow lines are clear and the rising angle of the streamline meets the requirements.The crack of the cracked sample is straight and smooth and shows"V"shape.The fracture is brittle fracture.There is a certain amount of oxide inclusions inside the crack.The microstructure of the weld of cracked ERW welded pipe is pearlite+ferrite,the heat affected zone of the weld is wide,and the metal flow line is not obvious.It is concluded that the cause of the weld fracture is the"cold welding"during welding.In the tensile test,the fracture position of the uncracked sample during grooving is at the base metal,and the fracture position of the cracking sample during grooving is the weld."Cold welding"during the welding and oxide inclusions in the weld,etc,all reduce the strength of the weld.

关 键 词：ERW焊管 冷焊 氧化物夹杂 微观组织 拉伸试验 

分 类 号：TG453.9[金属学及工艺—焊接]