稀土Yb2O3对TC4钛合金激光焊接头超塑变形行为的影响

Effect of rare earth Yb2O3 on superplastic deformation behavior of laser welded TC4 titanium alloy

摘要:

通过添加稀土Yb2O3提高TC4钛合金激光焊缝的超塑性变形能力，改善接头的超塑性变形均匀性。研究结果表明，Yb2O3的加入能够降低焊缝超塑性变形流变应力，提高延伸率，增加接头变形均匀系数值。随着Yb2O3含量增加，焊缝纵向峰值流变应力和延伸率均先降低再升高，在6%时峰值流变应力最低为11.9MPa；延伸率最高为592.3 %，此时焊缝区域组织等轴化程度最高，焊缝的超塑性最好。横向变形时随着Yb2O3含量的增加，接头变形均匀系数K值呈现先增加后减小的趋势，含量为6 wt.%时的试样K值取到最大值为0.209。

Abstract:

By adding rare earth Yb2O3, the superplastic deformation ability of laser weld of TC4 titanium alloy is improved, and the superplastic deformation uniformity of joint is improved. The results show that the addition of Yb2O3 can reduce the flow stress of weld superplastic deformation, improve the elongation and increase the uniform coefficient of joint deformation. With the increase of Yb2O3 content, the longitudinal peak flow stress and elongation of weld first decrease and then increase, and the peak flow stress is 11.9MPa at 6%. The highest elongation was 592.3 %. With the increase of Yb2O3 content in transverse deformation, the joint deformation uniformity coefficient K increases first and then decreases. When the content of Yb2O3 is 6 wt.%, the maximum K value of the sample is 0.209.