小直径2205双相不锈钢管对接焊接头组织与性能研究  

Microstructure and Properties of Butt Welding Joint of Small Diameter 2205 Duplex Stainless Steel Pipe

作　　者：李博锋 杨光[3] 袁宝 王亮[1,2] LI Bofeng;YANG Guang;YUAN Bao;WANG Liang(Baoji Petroleum Steel Pipe Co.,Ltd.,Baoji 721008,Shaanxi,China;China National Engineering Research Center for Petroleum and Natural Gas Tubular Goods,Baoji 721008,Shaanxi,China;The Sixth Oil Production Plant of Daqing Oilfield,Daqing 163114,HeiLongjiang,China)

机构地区：[1]宝鸡石油钢管有限责任公司,陕西宝鸡721008 [2]国家石油天然气管材工程技术研究中心,陕西宝鸡721008 [3]大庆油田第六采油厂,黑龙江大庆163114

出　　处：《焊管》2021年第2期7-10,15,共5页Welded Pipe and Tube

基　　金：中国石油天然气股份有限公司科学研究与技术开发项目“煤炭地下气化关键技术研究与先导试验”(项目编号GF2019E-25)。

摘　　要：针对2205双相不锈钢管采用钨极氩弧焊工艺进行了对接焊试验,通过金相组织观察、显微硬度测试、拉伸强度测试、抗内压试验以及晶间腐蚀试验等,分析了焊接接头的组织与性能。结果显示:焊缝组织中奥氏体以条状、岛状或块状分布于铁素体基体上,奥氏体比例约为42%;热影响区中奥氏体以块状或片状分布于铁素体周围,铁素体晶粒明显长大,呈等轴状,奥氏体比例约为35%;焊接接头硬度分布均匀,强度高于母材,塑性和抗内压性能良好;焊接接头抗晶间腐蚀性能满足GB/T 4334—2008要求,点蚀试验后接头表面未发现点蚀坑,平均腐蚀速率为7.623 mdd,满足ASTM A923标准C法中的规定。对于小直径2205双相不锈钢管的对接焊,采用小线能量、多层焊的工艺能够获得合理的双相组织比例,并能有效控制有害析出物,进而确保焊接接头良好的力学和耐蚀性能。The butt welding test of 2205 duplex stainless steel pipe was carried out by TIG welding process.The microstructure and properties of welded joint were analyzed by metallographic observation,microhardness test,tensile strength test,internal pressure test and intergranular corrosion test.The results show that in weld miscrostructure austenite is distributed on ferrite matrix in strip,island or block shapes,and proportion of austenite is about 42%.In heat affected zone,austenite is distributed around ferrite in block or sheet shapes,ferrite grains grow up obviously and are equiaxed,and the proportion of austenite is about 35%.The hardness distribution of welded joint is uniform,the strength is higher than that of base metal,and the plasticity and internal pressure resistance are good.The intergranular corrosion resistance of the welded joint meets the GB/T 4334—2008 standard.No pitting was found on the surface of the joint after pitting,and the average corrosion rate is 7.623 mdd,which meets the requirements of ASTM A923 standard C method.For butt welding of 2205 duplex stainless steel pipe with small diameter,the reasonable proportion of duplex structure can be obtained by using the process of small line energy and multi-layer welding,and the harmful precipitates can be effectively controlled to ensure the good mechanical and corrosion resistance of the welded joint.

关 键 词：2205双相不锈钢 焊接接头 力学性能 晶间腐蚀 点蚀 

分 类 号：TG444.74[金属学及工艺—焊接]