Lattice defects generated by cyclic thermomechanical loading of superelastic NiTi wire

0563592 - FZÚ 2023 RIV CH eng J - Článek v odborném periodiku
Tyc, Ondřej - Heller, Luděk - Šittner, Petr
Lattice defects generated by cyclic thermomechanical loading of superelastic NiTi wire.
Shape Memory and Superelasticity. Roč. 7, č. 1 (2021), s. 65-88. ISSN 2199-384X. E-ISSN 2199-3858
Grant CEP: GA MŠMT(CZ) EF16_019/0000760; GA ČR(CZ) GA20-14114S; GA ČR GA18-03834S; GA MŠMT LM2015087
Grant ostatní: OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institucionální podpora: RVO:68378271
Klíčová slova: cyclic stability * dislocations * NiTi materials * mechanical behaviour * stress-induced martensitic transformation * twinning * thermal cycling
Obor OECD: Condensed matter physics (including formerly solid state physics, supercond.)
Způsob publikování: Omezený přístup
https://doi.org/10.1007/s40830-021-00315-4

Cyclic instability of stress-strain-temperature functional responses of NiTi is presumably due to the plastic deformation accompanying martensitic transformation proceeding under external stress. In order to obtain systematic experimental evidence on this, we have performed series of cyclic thermomechanical loading tests (10 cycles) on superelastic NiTi wires with nanocrystalline microstructure, evaluated accumulated unrecovered strains and analysed permanent lattice defects created during the cycling by TEM. The accumulated unrecovered strains and density of lattice defects increased with increasing temperature and stress, at which the forward and/or reverse transformation proceeded. It did not correlate with the temperature and stress applied in the test as such.
Trvalý link: https://hdl.handle.net/11104/0335504