The microstructure evolution of as-rolled Ti-45Al-9Nb-0.3Y alloy as well as the nanohardness ofβ/B2 matrix was investigated by means of scanning electron microscopy (SEM) in backscattered electron mode (BSE) mode, tr...The microstructure evolution of as-rolled Ti-45Al-9Nb-0.3Y alloy as well as the nanohardness ofβ/B2 matrix was investigated by means of scanning electron microscopy (SEM) in backscattered electron mode (BSE) mode, transmission electron microscopy (TEM) and nanoindentation. This high Nb containing TiAl based alloy was rolled with 50%, 60%, 65% reduction, respectively. Omega phase precipitated in B2 phase with an orientation relationship of {110}β//{1120}ω and <111>β//<0001>ω. Moreover, with the increase of de-formation reduction, rod-like structure which was formed inγ grain transformed from (α2+γ) lamellae structure intoα2 phase only. Addi-tionally, nanoinentation experiment revealed that the precipitation hardening ofω phase increased the hardness ofβ/B2 phase.展开更多
基金supported by the National Natural Science Foundation of China(51504163)the State Key Laboratory for Advanced Metal and Materials foundation(2014-ZD06,2013-ZD06)+1 种基金the Special/Youth Foundation of Taiyuan University of Technology(2013T004,2013T003)the Qualified Personnel Foundation of Taiyuan University of Technology(tyut-rc201342a,tyut-rc201343a)
文摘The microstructure evolution of as-rolled Ti-45Al-9Nb-0.3Y alloy as well as the nanohardness ofβ/B2 matrix was investigated by means of scanning electron microscopy (SEM) in backscattered electron mode (BSE) mode, transmission electron microscopy (TEM) and nanoindentation. This high Nb containing TiAl based alloy was rolled with 50%, 60%, 65% reduction, respectively. Omega phase precipitated in B2 phase with an orientation relationship of {110}β//{1120}ω and <111>β//<0001>ω. Moreover, with the increase of de-formation reduction, rod-like structure which was formed inγ grain transformed from (α2+γ) lamellae structure intoα2 phase only. Addi-tionally, nanoinentation experiment revealed that the precipitation hardening ofω phase increased the hardness ofβ/B2 phase.