We compared twinning systems in Cu–Ni–Al and Ni–Mn–Ga single crystals from macroscale down to atomic scale. Using a newly developed formalism, we studied the twinning stress or mobility and microstructure of the equivalent twin boundaries. In Cu–Ni–Al, compound twinning exhibits the twinning stress of 1–2 MPa, and Type II twinning stress is approximately 20 MPa, which is much higher than the twinning stress for Type II in Ni–Mn–Ga (0.1–0.3 MPa). No temperature dependence was found for twinning stress of Type II in either alloy. Transmission electron microscopy revealed that in contrast to Ni–Mn–Ga, there was no internal twinning in Cu–Ni–Al, only stacking faults. The highest density of stacking faults was observed in the presence of Type I twin boundaries. The extremely low twinning stress may be associated with the deep hierarchy of twinning in Ni–Mn–Ga.
SMA Single crystals Martensite Twinning stress TEM
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This work has been financially supported by the Czech Science Foundation grant No. 14-36566G (AdMat), and furthermore by project LM2015087 of the Czech Ministry of Education, Youth and Sports. M. V. would like to acknowledge financial support by the grant SGS16/249/OHK4/3T/14. M. K. would like to acknowledge financial support of the ERDF in the frame of the project No. CZ.02.1.01/0.0/0.0/15_003/0000485.
Heczko O, Scheerbaum N, Gutfleisch O (2009) Magnetic shape memory phenomena. In: Liu JP et al (eds) Nanoscale magnetic materials and applications. Springer Science + Business Media, New York, pp 399–439CrossRefGoogle Scholar
Heczko O (2014) Magnetic shape memory effect and highly mobile twin boundaries. Mater Sci Technol 30:1559–1578CrossRefGoogle Scholar
Novak V, Sittner P, Ignacova S, Cernoch T (1999) Transformation behavior of prism shaped shape memory alloy single crystals. Mater Sci Eng A-Struct Mater Prop Microstruct Process 438:755–762Google Scholar
Basinski ZS, Christian JW (1954) Crystallography of deformation by twin boundary movements in indium-thallium alloys. Acta Metall 2:101–116CrossRefGoogle Scholar
Otsuka K, Wayman CM (1998) Shape Memory Materials. Cambridge University Press, CambridgeGoogle Scholar
Vronka M, Seiner H, Heczko O (2017) Temperature dependence of twinning stress—analogy between Cu–Ni–Al and Ni–Mn–Ga shape memory single crystals. Philos Mag 97:1479–1497CrossRefGoogle Scholar
Overholser RW, Wuttig M, Neumann DA (1999) Chemical ordering in Ni–Mn–Ga Heusler alloys. Scr Mater 40:1095–1102CrossRefGoogle Scholar
Straka L, Heczko O, Sozinov A (2011) Highly mobile twinned interface in 10M modulated Ni–Mn–Ga martensite: analysis beyond the tetragonal approximation of lattice. Acta Mater 59:7450–7464CrossRefGoogle Scholar
Kellis D, Smith A, Ullakko K, Müllner P (2012) Oriented single crystals of Ni–Mn–Ga with very low switching field. J Cryst Growth 359:64–68CrossRefGoogle Scholar
Straka L, Hanninen H, Heczko O (2011) Temperature dependence of single twin boundary motion in Ni–Mn–Ga martensite. Appl Phys Lett 98:141902CrossRefGoogle Scholar
Bhattacharya K (2004) Microstructure of martensite: how it forms and how it gives rise to the shape memory effect. Oxford University Press, OxfordGoogle Scholar
Sari U, Aksoy I (2006) Electron microscopy of 2H and 18R martensites in Cu-11.92 wt% Al-3.78 wt% Ni shape memory alloy. J Alloy Compd 417:138–142CrossRefGoogle Scholar
Chulist R, Straka L, Sozinov A, Lippmann T, Skrotzki W (2013) Modulation reorientation in 10M Ni–Mn–Ga martensite. Scr Mater 68:671–674CrossRefGoogle Scholar
Seiner H, Straka L, Heczko O (2014) A microstructural model of motion of macro-twin interfaces in Ni–Mn–Ga 10M martensite. J Mech Phys Solids 64:198–211CrossRefGoogle Scholar
Shield TW (1995) Orientation dependence of the pseudoelastic behaviour of single crystals of Cu–Al–Ni in tension. J Mech Phys Solids 43:869–895CrossRefGoogle Scholar
Straka L, Soroka A, Seiner H, Hanninen H, Sozinov A (2012) Temperature dependence of twinning stress of Type I and Type II twins in 10M modulated Ni–Mn–Ga martensite. Scr Mater 67:25–28CrossRefGoogle Scholar
Heczko O, Kopecky V, Sozinov A, Straka L (2013) Magnetic shape memory effect at 1.7 K. Appl Phys Lett 103:072405CrossRefGoogle Scholar
Ge Y, Zarubova N, Heczko O, Hannula SP (2015) Stress-induced transition from modulated 14M to non-modulated martensite in Ni–Mn–Ga alloy. Acta Mater 90:151–160CrossRefGoogle Scholar
Zarubova N, Ge Y, Heczko O, Hannula SP (2013) In situ TEM study of deformation twinning in Ni–Mn–Ga non-modulated martensite. Acta Mater 61:5290–5299CrossRefGoogle Scholar