Preferred orientation transition mechanism of faceted-growth materials with FCC structure: Competitive advantage depends on 3D microstructure morphologies

摘要

We investigated the three-dimensional microstructure morphologies of faceted-growth materials with face-centered cubic structure in the twin-related growth mode. Based on the twin-related growth mode, we obtained the total of five morphology configurations for [101]- and [112]-oriented grains, three of which were identified by our experimental studies in Tb0.3Dy0.7Fe1.95 alloys. The [101]- and [112]-oriented grains exhibit different morphological transition processes and, accordingly, different spatial occupation capacities, eventually leading to the transition of axially preferred orientation during directional solidification. (C) 2017 Elsevier B.V. All rights reserved.