不同工艺参数下0Cr18Ni9钢薄壁管脉冲钨极氩弧焊接头的组织与拉伸性能  

Microstructures and Tensile Properties of 0Cr18Ni9 Steel Thin-Wall Tube Welded Joints by P-TIG Under Different Process Parameters

作　　者：李宁 刘少龙 丁雪松 徐雨红 范文磊 苏焕朝 王博玉 LI Ning;LIU Shaolong;DING Xuesong;XU Yuhong;FAN Wenlei;SU Huanchao;WANG Boyu(Shuozhou Thermal Power Branch,Huadian Power International Co.,Ltd.,Shuozhou 036000,China;Huadian Shanxi Energy Co.,Ltd.,Taiyuan 030006,China;School of Materials Science and Engineering,Xi′an University of Technology,Xi’an 710048,China)

机构地区：[1]华电国际电力股份有限公司朔州热电分公司,朔州036000 [2]华电山西能源有限公司,太原030006 [3]西安理工大学材料科学与工程学院,西安710048

出　　处：《机械工程材料》2022年第2期58-62,共5页Materials For Mechanical Engineering

摘　　要：采用脉冲钨极氩弧焊(P-TIG)对规格为Ф14 mm×2 mm的0Cr18Ni9钢管进行焊接,研究50%脉宽比以及不同基值电流(20~30 A)、峰值电流(40~60 A)、脉冲频率(0.3,0.5 Hz)下接头的组织及拉伸性能。结果表明:不同工艺参数下接头焊缝区组织均为奥氏体+δ铁素体,但δ铁素体形态及含量有明显差异,热影响区奥氏体晶粒发生明显粗化。当脉冲基值电流为20 A,峰值电流为40 A,脉冲频率为0.3 Hz时,接头焊缝区δ铁素体呈蠕虫状,含量较多,热影响区奥氏体晶粒尺寸较小,接头拉伸性能最优,屈服强度为401.38 MPa,抗拉强度为701.51 MPa,屈强比为0.57,断口由形状均匀且尺寸较小的等轴韧窝组成。Pulse tungsten inert gas arc welding(P-TIG)was applied to weld 0 Cr18 Ni9 steel tubes with specification ofФ14 mm×2 mm,and the microstructure and tensile properties of joints under different base current(20-30 A),peak current(40-60 A),pulse frequency(0.3,0.5 Hz)and pulse width ratio of 50%were studied.The results show that the microstructures of the weld of joints under different process parameters were all austenite+δferrite,but the shape and content of theδferrite were significantly different;the austenite grains in the heat-affected zone were significantly coarsened.Under the pulse base current of 20 A,the peak current of 40 A and the pulse frequency of 0.3 Hz,the ferrite in the weld of the joint was vermicular with relatively high content,and the austenite grain size in the heat affected zone was small;the tensile properties of the joint was the best with yield strength of 401.38 MPa,tensile strength of 701.51 MPa and yield ratio of 0.57,and the fracture was composed of equiaxed dimples with uniform shape and small size.

关 键 词：脉冲钨极氩弧焊 奥氏体不锈钢管 Δ铁素体 拉伸性能 

分 类 号：TG407[金属学及工艺—焊接]