中文摘要：

对经近等温锻造后的Ti-22Al-25Nb/TC11双合金电子束焊接接头进行了梯度热处理与双重热处理,采用OM、TEM观察了Ti-22Al-25Nb/TC11双合金接头界面组织,并对其室温性能进行了对比分析。结果表明,梯度热处理后双合金接头Ti-22Al-25Nb基体析出相以细小颗粒状α2相为主,TC11基体出现网状组织;双重热处理后Ti-22Al-25Nb基体以短棒状的O相为主,TC11基体以魏氏组织为主;双重热处理后Ti-22Al-25Nb/TC11双合金接头的室温力学性能均低于梯度热处理后的双合金接头,这与其焊缝区析出的α相增加有关。因此,梯度热处理优异于双重热处理。

英文摘要：

The Ti-22Al-25 Nb / TC11 duplex alloy welded joint after near isothermal forging was treated with gradient heat treatment and double heat treatment. The interfacial microstructure of welded joint was observed by optical microscope（ OM）,transmission electron microscopy（ TEM）,and its room temperature properties was analyzed by tensile test contrastively. The results show that the precipitate phase in Ti-22Al-25 Nb matrix of duplex alloy welded joint after gradient heat treatment consists of granular α2phase,and net-like microstructure appears in the TC11 matrix; Ti-22Al-25 Nb matrix after double heat treatment consists of short column of O phase,widmannstatten structure is formed mainly in the TC11 matrix. The room-temperature mechanical property of Ti-22Al-25 Nb / TC11 duplex alloy joint after double heat treatment is lower than that gradient heat treatment which related to the increase of α phase. Therefore,gradient heat treatment is better than double heat treatment.