The grain boundary character distribution of a fully-orthorhombic Ti–25Al–24Nb(at.%) alloy
نویسنده
چکیده
The grain boundary character distribution (GBCD) of a fully-orthorhombic (O) Ti–25Al–24Nb (at.%) microstructure was investigated using electron backscatter diffraction (EBSD). The fine-grained (GS=17 lm) equiaxed microstructure was processed by hot forging and hot-rolling operations performed below the body-centered cubic (bcc) phase transus temperature followed by heat treatment in the O-phase field at 875 C. Nearly all the O/O grain boundaries were greater than 15 degrees misoriented and such boundaries exhibited the highest frequencies at misorientations of approximately 65 ( 26% of all grain boundaries) and 90 ( 10% of all grain boundaries). Twin-related O-phase variant interfacial (110) planes were identified and such boundaries represented 39% of all the O/O grain boundaries with 65 misorientation about [001]. 2004 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.
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