About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
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Symposium
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Characterization of Minerals, Metals and Materials
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Presentation Title |
Structure and Substructure Characterization of Ni50.3Ti29.7Hf20 High-temperature Shape Memory Alloy |
Author(s) |
Jiaqi Dong, Umale Tejas, Benjamin Young, Dexin Zhao, Ibrahim Karaman, Kelvin Xie |
On-Site Speaker (Planned) |
Jiaqi Dong |
Abstract Scope |
Twinning types and martensite interfaces play a significant role in the cyclic stability and fatigue life of shape memory alloys (SMAs). Therefore, we investigate the structure and substructure of the aged and solution-treated martensitic Ni50.3Ti29.7Hf20 high-temperature SMA in detail by transmission electron microscopy and precession electron diffraction (PED). Most martensite plates contain high-density internal (0 0 1) compound twins. Orientation relationships between martensite variants were studied using PED. In the solution-treated sample, (1 1 0.64) Type II twins and (1 1 1) Type I twins were observed, as well as the junction planes (i.e. (1 1 1) in variant A are parallel to (1 1 0.64) in variant B). (0 1 1) type I twin was observed in aged samples. Some of these orientation relationships are rarely observed in other NiTi or NiTiHf SMAs, which offers new insight to understand the phase transformation behavior in Ni50.3Ti29.7Hf20 SMAs. |
Proceedings Inclusion? |
Planned: |
Keywords |
Characterization, High-Temperature Materials, |