钢轨对接超窄间隙焊接试验  

Ultra-narrow gap butt welding of steel rail

作　　者：朱亮[1] 王洪涛[1] 符平坡[1] 

机构地区：[1]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,730050

出　　处：《焊接》2012年第3期10-13,69,共4页Welding & Joining

基　　金：国家自然科学基金资助项目(50775105)

摘　　要：利用焊剂带约束电弧超窄间隙焊接方法,对U71Mn钢轨对接进行了探索性试验研究。使用H08Mn2Si焊丝,通过34层焊道将坡口间隙约4 mm的钢轨焊接完成,单层焊接线能量为0.6 kJ/mm。试验表明焊前预热温度大于400℃可有效消除冷裂纹。在不预热的情况下,这种超窄间隙焊接接头热影响区和焊缝的硬度较高;预热可使焊缝硬度下降到与母材相当,同时使热影响区硬度略有下降。A tentative investigation on butt welding of U71Mn steel rail was carried out by ultra-narrow gap welding with arc-constricting flux strip.The rail joint with groove gap of nearly 4 mm were obtained by weld bead of 34 layers and H08Mn2Si wire as the filler material,and the heat input of single weld bead was 0.6 kJ/mm.The results showed that preheating over 400℃before welding can eliminate cold cracking effectively. Without preheating,the hardness of heat-affected zone and that of welds were higher in this ultra-narrow gap welded joint;and with preheating, the hardness of welds can be lower to be equivalent to the level of the base metal,and the hardness of heat-affected zone can also be decreased slightly.

关 键 词：钢轨焊接 超窄间隙焊接 预热温度 

分 类 号：TG444.74[金属学及工艺—焊接]