9Ni钢焊条电弧焊焊接接头的热裂纹分析  

Analysis of 9Ni Steel Electrode Arc Welding Welded Joint Hot Cracks

作　　者：石浩江[1] 李欣雨[2] 李宁[1] 蒋勇[2] 颜家振[1] 杨飞[2] 郑义[1] 

机构地区：[1]四川大学制造科学与工程学院,成都610065 [2]四川大西洋焊接材料股份有限公司,四川自贡643000

出　　处：《焊管》2016年第12期27-30,共4页Welded Pipe and Tube

基　　金：四川省科技支撑计划"大型LNG储罐用焊接材料关键技术及产业化研究"(项目编号2015KJT0072-2015GZ0062);*

摘　　要：为了找到9Ni钢焊条电弧焊焊接接头产生热裂纹的原因,采用Φ3.2 mm规格ENi Cr Mo-6电焊条对尺寸为500 mm×200 mm×10 mm的9Ni钢试样进行了电弧焊试验,并通过金相显微组织分析、直读光谱分析等方法,分析了焊接接头的显微组织与化学成分。分析结果表明,熔敷金属的结晶形态为具有强烈方向性的树枝晶,枝晶偏析严重;焊接接头熔敷金属沿着晶界产生热裂纹;熔敷金属中Pb在晶界的偏析是导致热裂纹产生的主要因素。最后给出了预防该类焊接热裂纹的具体措施。In order to find the hot crack reason of 9Ni steel electrode arc welding welded joint, it adopted Φ3.2 mm ENi Cr Mo-6 electrode to carry out electric-arc welding test on 500 mm ×200 mm ×10 mm 9Ni steel sample, through metallographic microstructure analysis, direct reading spectrometry method and other methods, the microstructure and chemical composition of welded joint were analyzed. The analysis results indicated that the crystal morphology of deposited metal was dendrite with strong directivity, and dendritic segregation was serious; the hot cracks generated along the deposited metal boundary; the segregation of Pb in boundary in deposited metal was the main factor caused hot crack. Finally it put forward the concrete measures to prevent this kind of welding hot cracks.

关 键 词：焊接 9NI钢 焊条电弧焊 显微组织 焊接接头 热裂纹 

分 类 号：TG406[金属学及工艺—焊接]