• Published:

In Situ Neutron Diffraction Analyzing Stress-Induced Phase Transformation and Martensite Elasticity in [001]-Oriented Co49Ni21Ga30 Shape Memory Alloy Single Crystals


Recent studies demonstrated excellent pseudoelastic behavior and cyclic stability under compressive loads in [001]-oriented Co–Ni–Ga high-temperature shape memory alloys (HT-SMAs). A narrow stress hysteresis was related to suppression of detwinning at RT and low defect formation during phase transformation due to the absence of a favorable slip system. Eventually, this behavior makes Co–Ni–Ga HT-SMAs promising candidates for several industrial applications. However, deformation behavior of Co–Ni–Ga has only been studied in the range of theoretical transformation strain in depth so far. Thus, the current study focuses not only on the activity of elementary deformation mechanisms in the pseudoelastic regime up to maximum theoretical transformation strains but far beyond. It is shown that the martensite phase is able to withstand about 5% elastic strain, which significantly increases the overall deformation capability of this alloy system. In situ neutron diffraction experiments were carried out using a newly installed testing setup on Co–Ni–Ga single crystals in order to reveal the nature of the stress–strain response seen in the deformation curves up to 10% macroscopic strain.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5


  1. 1.

    Otsuka K, Wayman CM (1999) Shape memory materials. Cambridge University Press, Cambridge

    Google Scholar 

  2. 2.

    Lagoudas DC (2008) Shape memory alloys: modeling and engineering applications. Springer, New York

    Google Scholar 

  3. 3.

    Sehitoglu H, Patriarca L, Wu Y (2017) Shape memory strains and temperatures in the extreme. Curr Opin Solid State Mater Sci 21:113–120

    Article  Google Scholar 

  4. 4.

    Ma J, Karaman I, Noebe RD (2010) High temperature shape memory alloys. Int Mater Rev 55:257–315

    Article  Google Scholar 

  5. 5.

    Otsuka K, Ren X (2005) Physical metallurgy of Ti-Ni-based shape memory alloys. Prog Mater Sci 50:511–678. https://doi.org/10.1016/j.pmatsci.2004.10.001

    Article  Google Scholar 

  6. 6.

    Firstov G, Van Humbeeck J, Koval Y (2004) High-temperature shape memory alloys. Mater Sci Eng A 378:2–10. https://doi.org/10.1016/j.msea.2003.10.324

    Article  Google Scholar 

  7. 7.

    Karakoc O, Hayrettin C, Bass M et al (2017) Effects of upper cycle temperature on the actuation fatigue response of NiTiHf high temperature shape memory alloys. Acta Mater 138:185–197. https://doi.org/10.1016/j.actamat.2017.07.035

    Article  Google Scholar 

  8. 8.

    Saghaian SM, Karaca HE, Tobe H et al (2017) High strength NiTiHf shape memory alloys with tailorable properties. Acta Mater 134:211–220. https://doi.org/10.1016/j.actamat.2017.05.065

    Article  Google Scholar 

  9. 9.

    Oikawa K, Ota T, Gejima F, Ohmori T, Kainuma R, Ishida K (2001) Phase equilibria and phase transformations in new B2-type ferromagnetic shape memory alloys of Co-Ni-Ga and Co-Ni-Al systems. Mater Trans 42:2472–2475

    Article  Google Scholar 

  10. 10.

    Vollmer M, Krooß P, Segel C et al (2015) Damage evolution in pseudoelastic polycrystalline Co-Ni-Ga high-temperature shape memory alloys. J Alloys Compd 633:288–295. https://doi.org/10.1016/j.jallcom.2015.01.282

    Article  Google Scholar 

  11. 11.

    Krooß P, Kadletz PM, Somsen C et al (2016) Cyclic degradation of Co49Ni21Ga30 high-temperature shape memory alloy: on the roles of dislocation activity and chemical order. Shape Mem Superelast 2:37–49. https://doi.org/10.1007/s40830-015-0049-5

    Article  Google Scholar 

  12. 12.

    Dadda J, Maier HJJ, Karaman I et al (2006) Pseudoelasticity at elevated temperatures in [001] oriented Co49Ni21Ga30 single crystals under compression. Scr Mater 55:663–666. https://doi.org/10.1016/j.scriptamat.2006.07.005

    Article  Google Scholar 

  13. 13.

    Dadda J, Maier HJ, Karaman I, Chumlyakov Y (2010) High-temperature in situ microscopy during stress-induced phase transformations in Co49Ni21Ga30 shape memory alloy single crystals. Int J Mater Res 101:1503–1513

    Article  Google Scholar 

  14. 14.

    Ren X, Otsuka K (1997) Origin of rubber-like behaviour in metal alloys. Nature 389:579–582. https://doi.org/10.1038/39277

    Article  Google Scholar 

  15. 15.

    Otsuka K, Ren XB (2001) Mechanism of martensite aging effects and new aspects. Mater Sci Eng A 312:207–218. https://doi.org/10.1016/s0921-5093(00)01877-3

    Article  Google Scholar 

  16. 16.

    Chernenko VA, Pons J, Cesari E, Zasimchuk IK (2004) Transformation behaviour and martensite stabilization in the ferromagnetic Co-Ni-Ga Heusler alloy. Scr Mater 50:225–229. https://doi.org/10.1016/j.scriptamat.2003.09.024

    Article  Google Scholar 

  17. 17.

    Niendorf T, Krooß P, Somsen C et al (2015) Martensite aging—avenue to new high temperature shape memory alloys. Acta Mater 89:298–304. https://doi.org/10.1016/j.actamat.2015.01.042

    Article  Google Scholar 

  18. 18.

    Krooß P, Niendorf T, Kadletz PM et al (2015) Functional fatigue and tension-compression asymmetry in [001]-oriented Co49Ni21Ga30 high-temperature shape memory alloy single crystals. Shape Mem Superelast 1:6–17. https://doi.org/10.1007/s40830-015-0003-6

    Article  Google Scholar 

  19. 19.

    Kustov S, Pons J, Cesari E, Van Humbeeck J (2004) Pinning-induced stabilization of martensite Part II. Kinetic stabilization in Cu-Zn-Al alloy due to pinning of moving interfaces. Acta Mater 52:3083–3096. https://doi.org/10.1016/j.actamat.2004.03.010

    Article  Google Scholar 

  20. 20.

    Dadda J, Maier HJ, Niklasch D et al (2008) Pseudoelasticity and cyclic stability in Co49Ni21Ga30 shape-memory alloy single crystals at ambient temperature. Metall Mater Trans A 39:2026–2039. https://doi.org/10.1007/s11661-008-9543-0

    Article  Google Scholar 

  21. 21.

    Monroe JA, Karaman I, Karaca HE et al (2010) High-temperature superelasticity and competing microstructural mechanisms in Co49Ni21Ga30 shape memory alloy single crystals under tension. Scr Mater 62:368–371. https://doi.org/10.1016/j.scriptamat.2009.11.006

    Article  Google Scholar 

  22. 22.

    Molnár P, Šittner P, Novák V, Lukáš P (2008) Twinning processes in Cu-Al-Ni martensite single crystals investigated by neutron single crystal diffraction method. Mater Sci Eng A 481–482:513–517. https://doi.org/10.1016/j.msea.2007.01.189

    Article  Google Scholar 

  23. 23.

    Kadletz PM, Krooß P, Chumlyakov YI et al (2015) Martensite stabilization in shape memory alloys—experimental evidence for short-range ordering. Mater Lett 159:16–19. https://doi.org/10.1016/j.matlet.2015.06.048

    Article  Google Scholar 

  24. 24.

    Kannarpady GK, Bhattacharyya A, Wolverton M et al (2008) Phase quantification during pseudoelastic cycling of Cu-13.1Al-4.0Ni (wt%) single-crystal shape memory alloys using neutron diffraction. Acta Mater 56:4724–4738. https://doi.org/10.1016/j.actamat.2008.05.028

    Article  Google Scholar 

  25. 25.

    Stebner AP, Vogel SC, Noebe RD et al (2013) Micromechanical quantification of elastic, twinning, and slip strain partitioning exhibited by polycrystalline, monoclinic nickel-titanium during large uniaxial deformations measured via in situ neutron diffraction. J Mech Phys Solids 61:2302–2330. https://doi.org/10.1016/j.jmps.2013.05.008

    Article  Google Scholar 

  26. 26.

    Keen DA, Gutmann MJ, Wilson CC (2006) SXD—the single-crystal diffractometer at the ISIS spallation neutron source. J Appl Crystallogr 39:714–722. https://doi.org/10.1107/S0021889806025921

    Article  Google Scholar 

  27. 27.

    Bhattacharya K (2003) Microstructure of martensite: why it forms and how it gives rise to the shape-memory effect. Oxford University Press, Oxford

    Google Scholar 

  28. 28.

    Laplanche G, Birk T, Schneider S, Frenzel J, Eggeler G (2017) Effect of temperature and texture on the reorientation of martensite variants in NiTi shape memory alloys. Acta Mater 127:143–152

    Article  Google Scholar 

  29. 29.

    Khalil-Allafi J, Schmahl WW, Reinecke T (2005) Order parameter evolution and Landau free energy coefficients for the B2 ↔ R-phase transition in a NiTi shape memory alloy. Smart Mater Struct 14:192–196. https://doi.org/10.1088/0964-1726/14/5/003

    Article  Google Scholar 

Download references


Financial support by the Deutsche Forschungsgemeinschaft (DFG) within the Research Unit Program “Hochtemperatur-Formgedächtnislegierungen” (Contract Nos. NI1327/3-2; SCHM 930/13-2) is gratefully acknowledged. Y.I.C. acknowledges the support from Russian Ministry of Education and Science (Project 16.6554.2017/6.7) and from The Tomsk State University Academic D.I. Fund Program (Project 8.140.2017).

Author information



Corresponding author

Correspondence to T. Niendorf.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Reul, A., Lauhoff, C., Krooß, P. et al. In Situ Neutron Diffraction Analyzing Stress-Induced Phase Transformation and Martensite Elasticity in [001]-Oriented Co49Ni21Ga30 Shape Memory Alloy Single Crystals. Shap. Mem. Superelasticity 4, 61–69 (2018). https://doi.org/10.1007/s40830-018-0156-1

Download citation


  • Shape memory alloy (SMA)
  • Martensitic phase transformation
  • In situ neutron diffraction
  • Martensite stabilization
  • Pseudoelasticity