Deformation twinning with different twin-boundary mobility in 2H martensite in Cu-Ni-Al shape memory alloy

0557447 - FZÚ 2023 RIV GB eng J - Journal Article
Ge, Yanling - Vronka, Marek - Veřtát, Petr - Karlík, M. - Hannula, S.-P. - Heczko, Oleg
Deformation twinning with different twin-boundary mobility in 2H martensite in Cu-Ni-Al shape memory alloy.
Acta Materialia. Roč. 226, Mar. (2022), č. článku 117598. ISSN 1359-6454. E-ISSN 1873-2453
R&D Projects: GA MŠMT(CZ) EF16_019/0000760; GA MŠMT LM2018110; GA ČR(CZ) GA21-06613S; GA ČR(CZ) GA17-00062S
Grant - others:OP VVV - SOLID21(XE) CZ.02.1.01/0.0/0.0/16_019/0000760
Institutional support: RVO:68378271
Keywords : shape memory alloys * deformation twinning * twinning stress * single crystal * HRTEM
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)
Impact factor: 9.4, year: 2022
Method of publishing: Limited access
https://doi.org/10.1016/j.actamat.2021.117598

Three possible twinning modes, Type I, Type II, and compound, as well as corresponding twin bound aries in 2H martensite of Cu69.4Ni3.4Al27.2 single crystal, were studied by X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). The results are discussed with regard to the sharply different twinning stress or twin-boundary mobility. In self-accommodated martensite, all three modes not only coexist but are crystallographically coupled. The compound twin boundary is a coherent coplanar mirror plane with the smallest twinning shear. The Type II twin boundary is also a coherent strain-free interface. The high index rational approximation of Type II twin boundary was determined by trace analysis with the help of stereographic projection. The approximation is in good agreement with irrational indices calculated from elastic continuum.
Permanent Link: https://hdl.handle.net/11104/0337791