| In this study, three alloys with nominal compositions(at%) of Ti48Al, TiAl-1V, TiAl-2V were prepared by plasma are melting and quenched from α₂＋γ, α＋γ and α phase regions, respectively. V additions to TiAl enhanced the plasticity of the alloy, and maximum plasticity in a compressive test occurred in the TiAl-2V alloy quenched from α＋γ phase regions. This is the reason that V additions to TiAl tend to refine grain size and increase twinning deformation. The peak stress of the alloys shows the same tendency as the strain. Vickers hardness of the alloys heat treated in the α phase region is, however, higher than the one in the α₂＋γ, α＋γ phase regions, and the reason is that α₂phase of the alloys heat treated in the α phase region is more than the one in the other regions. Therefore maximum hardness occurs at the TiAl-1V alloy heat treated in the α phase region. |
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