摘要
为研究钛合金管对接焊缝残余应力分布特性及其疲劳寿命,基于ABAQUS建立管对接焊缝焊接的数值模拟模型,采用双椭球形热源描述钨极惰性气体保护焊的热流分布特征,通过顺序耦合热弹塑性法求解焊接过程温度场与残余应力声,并利用全释放应变法进行试验验证;基于FE-SAFE平台,采用Brown-Miller模型预测了管对接焊缝的疲劳寿命。结果表明:仿真结果与实测结果高度吻合,焊缝表面中心存在较大的轴向压应力,最大为-240 MPa,残余应力从焊缝中心向母材逐渐由压应力转变为拉应力;在服役工况下的最大残余应力在焊缝热影响区,其服役寿命10^(4.2)次,满足服役寿命要求。研究建立的多场耦合仿真方法与寿命预测模型,为钛合金焊接工艺优化、焊缝质量控制及设备可靠性提升提供了理论支撑与技术参考。
To investigate the residual stress distribution characteristics and fatigue life of titanium alloy tube butt welds,a numerical simulation model for welding processes was established based on ABAQUS.The double ellipsoid heat source model was employed to characterize the heat flux distribution of tungsten inert gas(TIG)welding.The temperature field and residual stress during welding were solved using a sequentially coupled thermo-elastoplastic method,and experimental validation was conducted through the full strain release technique.Based on the FE-SAFE platform,the Brown-Miller model was applied to predict the fatigue life of the tube butt weld.Results indicate that the simulation results exhibit high consistency with experimental measurements.Significant axial compressive stress exists at the weld surface center,reaching a maximum value of-240 MPa.The residual stress gradually transitions from compressive to tensile stress when moving from the weld center toward the base metal.Under service conditions,the maximum residual stress occurs in the weld heat-affected zone,with a predicted service life of 10^(4.2) cycles,meeting the required service life specifications.The multi-field coupling simulation methodology and life prediction model developed in this study provide theoretical support and technical reference for optimizing titanium alloy welding processes,controlling weld quality,and enhancing equipment reliability.
作者
徐少峰
芦丽莉
林腾飞
韩铮
冯国才
龚亚
任黎平
XU Shaofeng;LU Lili;LIN Tengfei;HAN Zheng;FENG Guocai;GONG Ya;REN Liping(Nuclear Power Institute of China,Chengdu 610213,China)
出处
《电焊机》
2025年第12期9-16,25,共9页
Electric Welding Machine
关键词
钛合金管对接焊缝
残余应力
疲劳寿命
有限元仿真
焊接工艺
Titanium alloy tube butt welds
residual stress
fatigue life
finite element simulation
welding process
