|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Computational Design and Simulation of Materials (CDSM 2018): Meso/Macroscale Simulations
||Phase-field Simulation of Nanodomain Formation in Ti-Nb-O Alloys
||Yuya Ishiguro, Yuhki Tsukada, Toshiyuki Koyama
|On-Site Speaker (Planned)
β-type Ti-Nb alloys exhibit shape memory and superelasticity properties derived from the martensitic transformation from β phase (with a body-centered cubic lattice) to α" phase (with a face-centered orthorhombic lattice). In Ti-Nb-O alloys, the stress-strain hysteresis becomes slim when the O content is increased. This unique phenomenon has been considered to be related to the nanometer-sized martensite (nanodomain). In this study, a new formation process of nanodomain is proposed based on the phase-field simulations. First, it is shown that the O addition to the Ti-Nb alloys induces spinodal decomposition of β phase; β phase separates into O-rich β<SUB>1</SUB> phase and O-lean β<SUB>2</SUB> phase. Second, it is shown that β<SUB>1</SUB> phase can preferentially transforms to α" phase when the external stress is applied. The simulated stress-strain hysteresis becomes slim with increasing the O content. It is assumed that the formation of nanodomain can be explained by the diffusional-displacive transformation.
||Planned: Supplemental Proceedings volume