The formation of α at triple junctions of parent β phase in titanium alloys

ABSTRACT

We have examined the formation of α phase at grain boundary triple junctions of parent β in a metastable β titanium alloy with orientation imaging microscopy based on electron backscattered diffraction (EBSD). As in the case of α formed at grain boundaries of parent β grains, α at a triple junction also forms with the Burgers orientation relationship with one of the three neighbouring β grains. The experimental results are analyzed in terms of the deviation of the 36 possible α variants that can form at a triple junction from the Burgers orientation relationship with neighbouring grains.

KEYWORDS:

• Titanium alloys
• triple junction α
• orientation imaging microscopy

Acknowledgements

The authors are grateful to the Asian Office of Aerospace Research and Development (AOARD), Air Force Office of Scientific Research(AFOSR), USA for supporting this project through award number FA2386-16-1-4061 with Lt.Col. Scott Robertson as contract monitor. Discussions with Rongpei Shi and Yunzhi Wang on some aspects of determination of deviations from BOR are gratefully acknowledged. We are also grateful to one of the reviewers of this manuscript for suggesting that we evaluate special misorientations at triple junction for a ‘triple BOR criterion’

Disclosure statement

No potential conflict of interest was reported by the authors.

ORCID

Dipankar Banerjee http://orcid.org/0000-0002-9670-4824

Additional information

Funding

This work was supported by Asian Office of Aerospace Research and Development, Air Force Office of Scientific Research, USA: [Grant Number FA2386-16-1-4061].