Comparison of the Current Methods of Parent Austenite Reconstruction from Martensite Orientation Maps

Description

During the last decade, several methods have emerged for the reconstruction of the prior austenite phase from the orientation map of the product martensite phase. This work presents a systematic comparison of the efficiency and reliability of four such methods. Markov clustering and a stepwise cell-by-cell reconstruction procedure are compared with two novel reconstruction procedures, where the austenite orientations are initially determined for triple points. In the first new method, the triple points are used in combination with a seeded watershed-type algorithm for accurate determination of the parent austenite boundaries, followed by a full reconstruction. In the second new method, the triple points are used as nuclei for a step-by-step prior austenite growth procedure. When analyzing the reconstruction results, special attention is paid to the ability of the various methods to distinguish twinned prior austenite orientations from each other and to handle prior austenite in the cases where plastic deformation has occurred prior to the martensitic transformation. Standardized metrics are proposed to determine the quality of the reconstruction result. Alongside the results, an austenite reconstruction application has been developed for Matlab® to be used in conjunction with the MTEX crystallography analysis toolbox. The application can be used to employ any of the algorithms studied in this work, and it also contains analysis tools to verify the quality of any reconstruction result.

Period	26 Sept 2018
Event title	Materials Science and Engineering 2018 (MSE)
Event type	Conference
Location	Darmstadt, GermanyShow on map
Degree of Recognition	International