钛合金电子束焊接应力分析的有限元模型

Finite element for analysing EBW residual stress in titanium alloy plates

关键词:  有限元模型  钛合金  电子束焊接  残余应力  平板

Key words:  finite element model  titanium alloy  electron beam welding  residual stress  plate

摘要:

建立了两种钛合金平板电子束焊接应力场的数值分析模型,针对4 mm厚的TC11钛合金平板试件,计算分析不同计算模型对电子束焊接残余应力的影响。结果表明厚度为4 mm的平板电子束焊接接头,在焊缝及其近缝区很窄的区域内,存在着数值接近材料屈服极限的纵向残余拉应力,而表面横向残余应力则为压应力,且残余应力在厚度上也呈不均匀分布,数值计算模型应根据研究问题的特点来选取。

Abstract:

Two kinds of finite element model for analyzing electron beam welding(EBW) stress in titanium alloy plate were set up. For a 4mm thickness plate, the effect of different models on the calculated EBW residual stress was discussed. The results show that there is the longitude tensile residual stress in a very narrow region of welded joint, and the value of the residual tensile stress is close to the yield stress of the titanium alloy. Meanwhile there is the transverse residual compress stress on the surface of the heat-affected zone(HAZ). The residual stress value along the thickness direction is different in the HAZ. So the numerical model for analyzing EBW stress in titanium alloy thin plate should be carefully chosen in practical application.