30CrMnSi钢TIG焊冷裂纹形成机制  

Mechanism of cold welding cracks in 30CrMnSi steel joints welded by TIG method

作　　者：杨建国[1] 黄鲁永 张勇[1] 方洪渊[1] 

机构地区：[1]哈尔滨工业大学先进焊接与连接国家重点实验室,哈尔滨150001

出　　处：《焊接学报》2011年第12期13-16,113,共4页Transactions of The China Welding Institution

基　　金：中俄政府间科技合作资助项目(2007DFR70070)

摘　　要：针对中碳调质钢30CrMnSi在焊接时易出现焊接冷裂纹的问题,采用钨极惰性气体保护焊方法(TIG)对两端点固的30CrMnSi钢试件进行焊接,并分别采用金相及断口分析方法观察了相应的组织及焊接冷裂纹,提出了30CrMnSi钢焊接冷裂纹形成的机制,并探讨了基于控制热裂纹来防止冷裂纹的可行性.结果表明,熔敷金属在冷却过程中产生的热裂纹及晶间微裂纹将促进焊接冷裂纹的出现几率,研究结果对于指导中碳调质钢焊接冷裂纹的控制提出了有益的思路.As a kind of the medium-carbon quenching and tempering steel(MCQTT),30CrMoSi has been used widely in some industrial fields.However,just like some MCQTT,this steel faces such problems as cold cracking in the welded joints.In this research,the fracture and microstructure of the joints of 30CrMoSi steel welded by TIG method were studied by scanning electron microscopy(SEM)and optical microscopy(OM),respectively.More attention has been paid to the mechanism of the cold welding crack in 30CrMoSi steel.The results show that the hot welding cracks formed at high temperature are prone to inducing cold welding cracks.The potential method to control the cold welding crack in 30CrMoSi steel was discussed as well.

关 键 词：30CRMNSI钢 钨极惰性气体保护焊 冷裂纹 热裂纹 

分 类 号：TG403[金属学及工艺—焊接]