Crystallographic orientation relationships in the a-g' martensitic transformation in a Fe-Mn-Al-Ni system

JUAN MANUEL VALLEJOS, CESAR E. SOBRERO, MARTINA AVALOS, JAVIER W. SIGNORELLI, JORGE A. MALARRIA

JOURNAL OF APPLIED CRYSTALLOGRAPHY

WILEY-BLACKWELL PUBLISHING, INC

Lugar: Londres; Año: 2018 vol. 51

0021-8898

The Fe43.5Mn34Al15Ni7.5(at.%) alloy exhibits outstanding pseudoelastic behaviour over a wide range of temperatures. This alloy undergoes an unusual martensitic transformation from a disordered BCC (α) parent phase to a FCC(γ) product phase. In the present work, the orientations of the parent and product phases for quenched samples were analyzed by Electron Backscatter Diffraction. Bain, Kurdjumov-Sachs, Pitsch, Nishiyama-Wassermann and Greninger-Troiano orientationrelationship (OR) between parent and product phases were compared with experimental results. The Pitsch relationship appears to most suitably describe the α→γ´ martensitic transformation. This result provide experimental support to the dislocation-based heterogeneous Bogers-Burgers type transformation mechanism. No indications of variant selection were detected in the thermally activated transformations.