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以形变Ｔｉ－４７Ａｌ－２Ｍｎ－２Ｎｂ合金为对象，在７７～１３７３Ｋ和１０－５～１０－１ｓ－１应变速率范围内研究微量硼（ａ（Ｂ）＝１．０％）对ＴｉＡｌ合金显微组织和拉伸性能的影响．发现，１．０％Ｂ能有效地细化形变Ｔｉ－４７Ａｌ－２Ｍｎ－２Ｎｂ合金的近全片层组织，显著提高其中低温强度，改善中低温塑性，但不损害其高温强度，是提高ＴｉＡｌ合金综合性能的有效途径．还发现，除延脆转变温度附近外，１．０％Ｂ对形变ＴｉＡｌ合金断裂方式无明显影响．部分固溶于形变ＴｉＡｌ合金的硼原子可能与空位结合形成复合体，硼原子－空位复合体在一定温度下释放出空位，促进位错攀移，从而促进合金的延脆转变．
The deformation of Ti-47Al-2Mn-2Nb alloy was studied in the range of 77 ~ 1373K and 10-5 ~ 10-1s-1 strain rate of boron (a (B) = 1.0%) TiAl alloy microscopy Effect of Tissue and Tensile Properties. It is found that 1.0% B can effectively refine the near-complete lamellar microstructure of the deformed Ti-47Al-2Mn-2Nb alloy, significantly increase the low-temperature strength and improve the low-temperature plasticity without damaging the high temperature strength, An effective way to comprehensive performance. It was also found that 1.0% B had no significant effect on the fracture mode of the deformed TiAl alloy except near the ductile transformation temperature. The boron atoms partially dissolved in the deformed TiAl alloy may combine with vacancies to form a complex. The boron atom-vacancy complex releases vacancies at a certain temperature and promotes dislocation climbing so as to promote the transformation of the alloy.