中文摘要：

研究了热变形对Ti-24Al-15Nb-1.5Mo/TC 11双合金焊接界面持久性能的影响.在梯度热处理条件下,变形量为40％的试样持久寿命优于其他试样.在持久试验过程中,焊缝以及合金的热影响区是薄弱区域,断裂多发生在此.当焊缝以及合金热影响区中含有晶界α相时会降低持久性能;同时,Ti-24Al-15Nb-1.5Mo合金基体中的粗大α2相也是导致持久性能降低的不利因素.由于在持久试验过程中元素继续扩散,可以发现持久试验后Nb元素在焊缝中的含量明显增加.

英文摘要：

The effect of hot working conditions on the stress rupture properties of Ti-24Al-15Nb-1.5Mo/TC11 dual-alloy with electron beam welds has been evaluated.Under the gradient heat treatment,the stress rupture properties of the dissimilar alloy joints with 40% deformation degree are superior to the others.The weld and heat affected zone （HAZ） are the weak areas in the stress rupture experiment.The microstructures of weld and HAZ containing grain boundary α are not beneficial to the stress rupture property.Meanwhile,the grain boundaries of Ti-24Al-15Nb-1.5Mo base alloy with coarse α2 phases have a negative effect to stress rupture property.As the atoms diffusing,the content of Nb increases obviously in the weld after stress rupture experiment.