中文摘要：

采用不同初始组织的Ti-22Al-25Nb合金与TC11合金进行焊接,然后再用同样规范对焊件进行近等温锻造和热处理。利用OM对焊件接头的显微组织进行了观察,并拉伸测试了Ti-22Al-25Nb/TC11异种合金接头的强度。结果表明：焊前经固溶处理过的Ti-22Al-25Nb合金B2晶粗大,焊后经等温锻造和热处理之后析出的O相较多,使得焊接接头强度和塑性均有降低;Ti-22Al-25Nb/TC11异种合金接头的显微组织内含有O相、α相、β相及少量α2相。

英文摘要：

Ti-22Al-25 Nb alloy with different initial microstructure and TC11 were undergone uniform isothermal forging and heat treatment after welding. The microstructure and strength of the welded joint of Ti-22Al-25Nb/TC11 dissimilar alloy were investigated by optical microscope（OM） and tensile testing, respectively. The results show that after solid solution treatment, the B2 grains of Ti-22Al-25 Nb are bulky. The reasons for leading to reduction of strength and plasticity is that more phases of O precipitate during isothermal forging and heat treatment. There are phases of O, α, β and a little α2 within the microstructure of welded joint of Ti-22Al-25Nb/TC11 dissimilar alloy