A heuristic stereographic tool has been developed supporting identification of un-measurable parent β grain orientations in Ti alloys from electron back scattered diffraction (EBSD) without computation. The method involves the use of inverse pole figure (IPF) Euler angle color patterns of α laths in Burgers oriented α/β crystals. The approach employs the use of composite stereographic projections of two fundamental α/β variants of the Burgers orientation relationship (BOR), overlaid with a commonly used IPF Euler angle color scheme for α lath orientations. Use of the heuristic tool associates many α lath orientations via EBSD-IPF derived Euler angle color patterns with the required, but usually un-measurable parent β grain orientation. Results from use of the heuristic tool are compared with observations from EBSD-IPF scans that directly measured α lath and parent β grain orientations. A reference look-up table associating characteristic α lath color patterns with orientation of their underlying parent β grain is provided. It is shown that the use of the heuristic tool to determine orientations of interest enables identification of un-measurable parent β grain orientations rather than obtaining an approximate answer using complicated computational methods. The new tool yields fairly accurate results avoiding post-processing, and often does not require the presence of more than two or three variants.
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