EBSD characterisation of the B2 orientation in γ-TiAl based alloy

Abstract

Electron backscattered diffraction (EBSD) has been conducted to determine the orientation relationship of the remnant B2 phase in an α-solidified γ-Ti-45Al-2Nb-0.3Si (at. %) based intermetallic alloy. The morphology and microstructural characterisation was investigated using conventional methods. The results showed that the B2-grains exhibits a Blackburn orientation relationship (BOR) with the α2 grains viz. {111}B2 // {0001}α2 and {110}B2 // {11-20}α2. Moreover, mis-orientation axes of B2-grains were found in the clusters between <101> and <111> in 57-63° angles, in the Y0 directions. In addition, it was also observed that the overall B2 grains in the alloy structure was textured and comprised of high angle boundaries of misorientations above 15° angles.