Mechanical stabilization of martensite: comparison of Ni-Mn-Ga and Cu-Ni-Al shape memory single crystals

0499590 - FZÚ 2019 RIV PL eng J - Článek v odborném periodiku
Vronka, Marek - Straka, Ladislav - Seiner, Hanuš - Karlík, M. - Heczko, Oleg
Mechanical stabilization of martensite: comparison of Ni-Mn-Ga and Cu-Ni-Al shape memory single crystals.
Acta Physica Polonica A. Roč. 134, č. 3 (2018), s. 627-630. ISSN 0587-4246. E-ISSN 1898-794X
Grant CEP: GA ČR GA16-00043S; GA ČR GB14-36566G
Institucionální podpora: RVO:68378271 ; RVO:61388998
Klíčová slova: interfacial microstructures * martensite transformation * stress stabilization * shape memory alloy
Obor OECD: Materials engineering; Materials engineering (UT-L)
Impakt faktor: 0.545, rok: 2018

Newly developed formalism, regarding 2H modulated Cu-Ni-Al system as non-magnetic equivalent of Ni-Mn-Ga 10M modulated martensite provides the way to compare behaviour of these two shape memory alloys. Here we study the mechanical stabilization by mechanical stress in the single crystals of Ni50.7Mn27.7Ga21.6 (at.%) and Ni46Mn24Ga22Co4Cu4 exhibiting 10M and non-modulated martensite structures, respectively, and for comparison in Cu69.4Ni3.4Al27.2 2H martensite. The resulting shift of reverse transformation temperature was almost 50 K in the Cu-Ni-Al 2H martensite and about 6 K in Ni-Mn-Ga non-modulated martensite. In contrast, the shift was <1 K in 10M Ni-Mn-Ga martensite. From the comparison it follows that the negligible stabilization in modulated 10M Ni-Mn-Ga can be due to its deep twinning hierarchy and very high mobility of twin boundaries.
Trvalý link: http://hdl.handle.net/11104/0291804