钴基合金静叶片焊接裂纹力学因素研究

THE STUDY ON THE WELDING RESIDUAL STRESSES OF STATIC VANES

采用热弹塑性有限元技术,分析研究了Co基Stellite 31合金静叶片电子束焊接时产生焊接裂纹的力学因素、焊接残余应力、与焊接装夹方式及焊接工艺的关系.结果表明:焊接过程中产生的冷裂纹,主要由于焊接过程中产生的收缩力引起;焊接方向和焊件的装夹方式对接头中的残余应力分布有较大的影响;焊缝两端附近的残余应力分布和焊接方向有关,起焊端焊缝中心是拉应力,而在终焊端则是压应力;焊接速度及焊接线能量都对焊接残余应力分布有一定的影响.

In this paper, the residual stresses of static vanes in Stellite 31 alloy with electron beam welding were studied using the thermal elastic plastic finite element method. And the effects of the welding process on the residual stress distribution were carefully investigated. The results show that the welding direction will affect greatly on the residual stresses of the vanes, that the pull residual stress is found near the beginning of the weldment and the press residual stress near the end of weldments, and that the welding assemble equipment will affect the residual stress distribution of vanes with electron beam welding.