Effects of Gradient Annealing on the Microstructure and Rate-Dependent Thermomechanical Behavior of Nanocrystalline NiTi Shape Memory Alloy

Yan, Kai1,2; Yang, Siyu1; Xu, Jiacheng1; Ren, Fuzeng2; Sun, Qingping1,3

2022-10-01

10.1007/s40830-022-00390-1

Shape Memory and Superelasticity   影响因子和分区

2199-384X

2199-3858

A grain size gradient NiTi shape memory alloy, which contains distributed grain sizes within one piece of NiTi sample, would combine superior performances, such as large hysteresis and high fatigue life, high ductility, and strength, due to its gradient structures. This study illustrates the fabrication process, microstructure, and mechanical behavior of both cold-rolled and grain size gradient NiTi. An clear gradient structure has been confirmed by the experiments of this paper. The temperature of the cold-rolled specimen decreases during loading and increases during unloading, which may be mainly caused by the the thermoelastic effect in the linear elastic region and also possible inverse elastocaloric effect (R-B2 phase transition) induced by Ti2Ni and Ni3Ti precipitates. The temperature of the gradient annealed specimen shows a gradient temperature profile, and the temperature decreases slightly followed by an increase during loading, and then decreases and increases during unloading. The main reason for this phenomenon may be the competition among the thermoelastic effect, elastocaloric effect (B2-R phase transition) and inverse elastocaloric effect (R-B2 phase transition) induced by Ti2Ni and Ni3Ti precipitates.

Grain size gradient NiTi shape memory alloy Gradient annealing Phase transition Thermomechanical behavior

ESCI

英语

通讯

National Science Foundation of China[52122102] ; Hong Kong Research Grant Council (RGC) through the GRF grant[16239316] ; Project of Hetao Shenzhen-Hong Kong Science and Technology Innovation Cooperation Zone[HZQBKCZYB-2020083] ; Science, Technology and Innovation Commission of Shenzhen Municipality of China[SGDX2019081623360564]

Materials Science

Materials Science, Multidisciplinary

WOS:000875002600001

SPRINGER INT PUBL AG

Web of Science

1.Hong Kong Univ Sci & Technol, Dept Mech & Aerosp Engn, Hong Kong, Peoples R China
2.Southern Univ Sci & Technol, Dept Mat Sci & Engn, Shenzhen 518055, Guangdong, Peoples R China
3.HKUST Shenzhen Hong Kong Collaborat Innovat Res I, Shenzhen 518000, Guangdong, Peoples R China

Yan, Kai,Yang, Siyu,Xu, Jiacheng,et al. Effects of Gradient Annealing on the Microstructure and Rate-Dependent Thermomechanical Behavior of Nanocrystalline NiTi Shape Memory Alloy[J]. Shape Memory and Superelasticity,2022.

Yan, Kai,Yang, Siyu,Xu, Jiacheng,Ren, Fuzeng,&Sun, Qingping.(2022).Effects of Gradient Annealing on the Microstructure and Rate-Dependent Thermomechanical Behavior of Nanocrystalline NiTi Shape Memory Alloy.Shape Memory and Superelasticity.

Yan, Kai,et al."Effects of Gradient Annealing on the Microstructure and Rate-Dependent Thermomechanical Behavior of Nanocrystalline NiTi Shape Memory Alloy".Shape Memory and Superelasticity (2022).