摘要
利用符合弹塑性本构关系的数学模型,施加高斯旋转曲面体热源,建立了符合实际激光焊接过程的有限元分析模型。通过改变激光功率、焊接速度、光斑直径的取值,探讨TC4钛合金横向残余应力的变化规律。通过分析残余与瞬态应力分布,揭示激光焊接塑性应变的形成与横向残余应力的分布规律。结果显示,激光焊接规范改变对接头横向残余应力的影响有限,TC4钛合金激光焊接头横向残余应力以压应力为主,且峰值不大,只有试板两端出现了不利的横向残余应力分布模式。热源作用瞬间,位于已冷却部位的热源后部产生了压缩塑性应变。
The mathematical model with elastic-plastic constitutive equations was used.The Gaussian rotating curved face body heat resource was applied.The finite element analysis model which can meet with the realistic laser welding process was established.The variation law of transverse residual stress was explored by changing laser power,welding speed and spot diameter value on TC4 alloy.The plastic strain formation and transverse residual stress distribution were disclosed by analyzing residual and transient stress.The results show that the change of laser welding condition has limited impact on the transverse residual stress on the welded joints.TC4 laser welding transverse residual stress is mainly compressive stress,and the peak is not high,but there has negative residual stress distribution in the transverse mode at both ends of testing plate.The compression plastic strain in the cooling site at the rear of the heat resource is generated at the moment of heat resource acting.
出处
《热加工工艺》
CSCD
北大核心
2013年第21期155-158,共4页
Hot Working Technology
基金
西藏自治区自然科学基金资助项目(12KJZRYMY02)
西藏民族学院"青年学人培育计划"资助项目(12myQP09)
关键词
塑性应变
瞬态应力
焊接规范
应力梯度
plastic strain
transient stress
welding condition
stress gradient
