连续油管电阻焊热影响区不完全正火区的组织与性能  

Microstructure and properties of incompletely normalized area in coiled tubing heat affected zone of electric resistance welding

作　　者：李继红[1] 赵鹏康[1] 余晗[2] 毕宗岳[1,2] 张敏[1] 

机构地区：[1]西安理工大学材料科学与工程学院,陕西西安710048 [2]宝鸡石油钢管有限责任公司,陕西宝鸡721008

出　　处：《金属热处理》2012年第4期33-37,共5页Heat Treatment of Metals

基　　金：陕西省教育厅自然科学基金(00k904);陕西省重点学科建设专项基金(00X901)

摘　　要：采用热模拟技术、显微分析方法和力学性能测试等手段,对连续油管用母材的组织与性能进行了研究,并对连续油管直缝高频电阻焊焊接接头热影响区(HAZ)性能最薄弱的不完全正火区组织及性能的变化规律进行了分析。结果表明,在3种焊接工艺条件下,所获得不完全正火区组织变化并不明显,均为铁素体基体上均匀弥散分布有大量粒状贝氏体组织;而冲击吸收能量有较明显变化,在线能量为3.0和5.0 kJ/cm时,对应的冲击吸收能量分别为38.30和35.85 J,均比原有焊接工艺3.96 kJ/cm对应的冲击吸收能量(30.95 J)高;冲击断口形貌均以均匀韧窝为主,但2、3号工艺下断口韧窝大且深,说明韧性较好。通过以上分析,线能量为3.0 kJ/cm附近时可以获得最佳的组织与性能。Microstructrue and mechanical properties of coiled tubing base metal were studied by thermal simulation,microscopic analysis,mechanical properties test and other means.Then,the variation rules of the most vulnerable areas of HAZ of electric resistance welding were studied in welded joints.The results show that under the three welding procedures,mircostructure of incompletely normalized area changes slightly.A large number of granular bainite distributes in the ferrite matrix.There is significant variation in impact absorbed energy,when line energy is 3.0 and 5.0 kJ/cm,the impact absorbed energy are 38.30 and 35.85 J respectively,which are higher than impact absorbed energy 30.95 J corresponding line energy 3.96 kJ/cm.At the same time,there are a large number of uniform dimple-based in fracture surface,the dimples of sample 2 and 3 are larger and deeper,which are evidence for improving impact toughness.From the subsequent analysis,when the line energy is about 3.0 kJ/cm,the good microstructure and optimal property are obtained.

关 键 词：热模拟 焊接工艺 粒状贝氏体钢 电阻焊 

分 类 号：TG115.6[金属学及工艺—物理冶金]