Parent grain reconstruction from partially or fully transformed microstructures in MTEX

Frank Niessen; Tuomo Nyyssönen; Azdiar A Gazder; Ralf Hielscher

doi:10.1107/S1600576721011560

Parent grain reconstruction from partially or fully transformed microstructures in MTEX

J Appl Crystallogr. 2022 Feb 1;55(Pt 1):180-194. doi: 10.1107/S1600576721011560.

Authors

Frank Niessen^{1

2}, Tuomo Nyyssönen³, Azdiar A Gazder², Ralf Hielscher^{4

5}

Affiliations

¹ Department of Mechanical Engineering, Technical University of Denmark, 2800 Kongens Lyngby, Denmark.
² Electron Microscopy Centre, University of Wollongong, Wollongong, NSW 2500, Australia.
³ Swerim AB, 164 40 Kista, Sweden.
⁴ Fakultät für Mathematik, Technische Universität Chemnitz, 09126 Chemnitz, Germany.
⁵ Institute for Applied Analysis Faculty of Mathematics and Informatics, Technische Universität Bergakademie Freiberg, Prüferstrasse 9, Room 1.02, 09599 Freiberg, Germany.

Abstract

A versatile generic framework for parent grain reconstruction from fully or partially transformed child microstructures has been integrated into the open-source crystallographic toolbox MTEX. The framework extends traditional parent grain reconstruction, phase transformation and variant analysis to all parent-child crystal symmetry combinations. The inherent versatility of the universally applicable parent grain reconstruction methods and the ability to conduct in-depth variant analysis are showcased via example workflows that can be programmatically modified by users to suit their specific applications. This is highlighted by three applications, namely α'-to-γ reconstruction in a lath martensitic steel, α-to-β reconstruction in a Ti alloy, and a two-step reconstruction from α' to ɛ to γ in a twinning and transformation-induced plasticity steel. Advanced orientation relationship discovery and analysis options, including variant analysis, are demonstrated via the add-on function library ORTools.

Keywords: electron backscattering diffraction; orientation relationships (ORs); parent phase reconstruction; phase transformations.

Grants and funding

This work was funded by Teknologi og Produktion, Det Frie Forskningsråd grant DFF-8027-00009B to Frank Niessen; Australian Research Council grant LE0882613 to Azdiar Gazder; University of Wollongong.