摘要
为了提高不锈钢管的冷加工成形性能,进一步优化相应焊接工艺,在对汽车排气管激光焊接温度场进行数值模拟研究的基础上,分析激光焊接汽车排气管残余应力.在考虑网格的疏密过渡以及材料力学性能参数随温度的变化条件下,分析激光焊接不锈钢管残余应力演变过程及分布特点,即滚轮挤压量越小,平均残余应力越小,但容易出现咬边和未焊透,在局部产生应力集中,更容易在焊接管冷加工时出现开裂;激光焊接线能量减小,轴向残余应力区域变窄,峰值应力增加.将激光焊接残余应力与钨极氩弧焊(TIG)+激光焊的残余应力进行对比实验,结果表明,不锈钢管TIG+激光焊残余应力与激光焊接具有相似的分布,分布区域相对变宽,焊轴向残余应力比激光焊接小,提高了焊接管冷加工成型性能.
The residual stress field was calculated based on the numerical simulation of the temperature field of laser welding joint of stainless steel automobile vent pipe in order to improve the cold forming quality of ferrite stainless steel vent pipe and optimize its welding technology.The residual stress of stainless steel pipe was analyzed in laser welding considering the grid spacing transition and the mechanical property change of materials with temperature.Results showed that the average residual stress of welding seam was reduced but the undercut and incomplete penetration of welding seam easily appeared during the decreasing of roller pressure.Because the local stress concentration appeared,the cold forming of automobile vent pipe easily caused cracks.The axial residual stress distribution was narrow and the peak residual stress rose during decreasing heat input of laser welding.The residual stress in laser welding was compared with the residual stress in tungsten inert gas（TIG） welding＋ laser welding.Results showed that the residual stress distribution in TIG ＋ laser welding was wider than one in laser welding,the axial residual stress in TIG ＋ laser welding was smaller than one in laser welding,and the cold forming quality of automobile vent pipe was improved.
出处
《浙江大学学报（工学版）》
EI
CAS
CSCD
北大核心
2011年第1期136-140,共5页
Journal of Zhejiang University：Engineering Science
基金
哈尔滨工业大学现代焊接国家重点实验室基金资助项目(Welding08003)
宁波自然基金重点资助项目(2008A610031)
黑龙江省自然科学基金资助项目(E2007-01)
关键词
汽车排气管
激光焊接
残余应力
钨极氩弧焊
激光焊
automobile vent pipe
laser welding
residual stress
tungsten inert gas welding
laser welding
