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研究了各种显微组织TiAl基合金材料之间自体固态焊接实验结果表明，粗晶TiAl基合金与粗晶TiAl基合金作焊接对偶件时，在结合面上形成与基体组织不同的再结晶细晶组织.这种显微组织的差异及结合面上微孔隙的残存，导致焊接组构件的断裂主要发生在结合面上.如采用粗晶TiAl合金与细晶双态组织TiAl基合金对焊时，由于细晶TiAl基合金具有较好超塑性变形能力、在热压力作用下此部分材料可镶嵌入焊接对偶另一侧，得到较好的结合采用细晶TiAl基合金材料作对偶进行固态焊接时，由于对偶材料都具有良好的超塑性，因此，可以仅仅通过晶界滑移进行超塑性变形，得到完全结合的焊接界面，结合面上的显微组织与基体一致、焊接对偶件材料得到高的室温力学性能，其值高达σb＝533MPa；δ≈2%;此时，所有的拉伸试样的断裂都发生在非结合面上.
The experimental results of self-solid welding between TiAl-based alloys with various microstructures show that when the coarse-grained TiAl-based alloy is welded to the coarse-grained TiAl-based alloy, the recrystallized fine Crystal structure.This difference in microstructure and the residual micro-pores on the bonding surface, resulting in the fracture of the welded group member occurs mainly in the bonding surface.If the coarse grain TiAl alloy and fine grain dual-structure TiAl-based alloy butt welding , Fine grained TiAl-based alloy with better superplastic deformation ability, under the action of thermal stress, this part of the material can be embedded into the other side of the welding pair to obtain a better combination of fine grained TiAl-based alloy material for dual solid state welding , Because the dual material has a good superplasticity, so it can only superplastic deformation by grain boundary slip, to obtain a fully bonded welding interface, the microstructure on the bonding surface and the substrate, the welding of the mating material is high Room temperature mechanical properties, the value of up to σb = 533MPa; δ ≈ 2%; At this point, all the tensile specimen fracture occurred in the non-binding surface.