Heuristic determination of parent β matrix orientation from Burgers oriented α precipitates in Ti alloys

• Published in: Materials characterization Vol. 215; p. 114194
• Main Authors: Broderick, Thomas F., Viswanathan, Gopal B., Kloenne, Zachary T., Pilchak, Adam L., Fraser, Hamish L.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.09.2024
• Subjects: beta grain reconstruction; Burgers orientation relationship; EBSD; Phase transformation; Phase transformation; Burgers orientation relationship; EBSD; beta grain reconstruction
• ISSN: 1044-5803
• DOI: 10.1016/j.matchar.2024.114194

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. •A heuristic tool for identification of parent β orientations in Ti alloys without further computation.•Results are compared with observations from EBSD-IPF scans.•The tool identifies parent β orientations without using computational methods.