The 9th International Conference on Multiscale Materials Modeling

講演情報

Symposium

E. Deformation and Fracture Mechanism of Materials

[SY-E9] Symposium E-9

2018年11月1日(木) 09:45 〜 11:00 Room2

Chairs: Andrej Ostapovec(Institute of Physics of Materials ASCR, Czech Republic), Yujie Wei(Chinese Academy of Sciences, China)

[SY-E9] Atomistic study on the super-elasticity of single crystal bulk NiTi shape memory alloy under adiabatic condition

Bing Wang1, Guozheng Kang1, Qianhua Kan1, Wenping Wu2, Kun Zhou3, Chao Yu1 (1.School of Mechanics and Engineering, Southwest Jiaotong University, China, 2.School of Civil Engineering, Wuhan University, China, 3.School of Mechanical and Aerospace Engineering, Nanyang Technological University, Singapore)

The temperature-induced phase transition and the super-elasticity (from the stress-induced phase transition) of equiatomic single crystal bulk NiTi shape memory alloys are investigated by the molecular dynamics method. By the simulation to the thermo-mechanical response of the single crystal NiTi alloy along the <001>B2 under the compression/unloading and an adiabatic condition, the temperature change and the nucleation and growth of martensite transformation during the compression/unloading are discussed. The simulated results of molecular dynamics show that the single crystal bulk NiTi shape memory alloy exhibits a significant temperature change during the martensite transformation and its reverse under an adiabatic condition; moreover, a localized instability occurs apparently in the process of martensite transformation, which is closely related to the nucleation and growth rates of martensite phase; finally the effect of model size and strain rate on the thermo-mechanical response of the single crystal bulk NiTi alloy is also discussed, and no instability is observed in the simulated stress-strain curves if the model size is relatively larger, e.g., 8V0 and 13.824V0.