Journal of Materials Science

, Volume 50, Issue 22, pp 7473–7487 | Cite as

Thermally induced martensitic transformations in Cu-based shape memory alloy microwires

  • Nihan Tuncer
  • Lei Qiao
  • Raul Radovitzky
  • Christopher A. Schuh
Original Paper


Prior studies on shape memory alloys have identified size effects on the superelastic, i.e., stress-induced, hysteresis of martensitic transformations. However, literature on thermally induced transformations and size effects upon stored elastic energy is rather limited. In this work, a complementary sample size effect on the stored elastic energy of the transformation, and its effect on variant selection, is elaborated. Shape memory alloy microwires of a CuAlMnNi alloy are drawn with diameters varying between 45 and 255 μm and processed to obtain bamboo grain structures, where the grain boundaries lay almost perpendicular to the wire axis. Calorimetric and thermomechanical analyses of the microwires establish a decreasing contribution of stored elastic energy to the free energy of martensitic transformation as the wire diameter is reduced. This in turn affects the transformation ranges and macroscopic strain generated in constrained thermal cycling. The effect is shown to be associated with a decrease in number of interacting martensite variants as well as relaxation on free surfaces. The presented results indicate that thermal actuation of lightly biased SMA wires is enhanced in finer wires.


  1. 1.
    Chen Y, Schuh CA (2011) Size effects in shape memory alloy microwires. Acta Mater 59:537–553. doi:10.1016/j.actamat.2010.09.057 CrossRefGoogle Scholar
  2. 2.
    Ozdemir N, Karaman I, Mara NA et al (2012) Size effects in the superelastic response of Ni54Fe19Ga27 shape memory alloy pillars with a two stage martensitic transformation. Acta Mater 60:5670–5685. doi:10.1016/j.actamat.2012.06.035 CrossRefGoogle Scholar
  3. 3.
    Ueland SM, Schuh CA (2012) Superelasticity and fatigue in oligocrystalline shape memory alloy microwires. Acta Mater 60:282–292. doi:10.1016/j.actamat.2011.09.054 CrossRefGoogle Scholar
  4. 4.
    Chen Y, Zhang X, Dunand DC, Schuh CA (2009) Shape memory and superelasticity in polycrystalline Cu–Al–Ni microwires. Appl Phys Lett 95:171906. doi:10.1063/1.3257372 CrossRefGoogle Scholar
  5. 5.
    Ueland SM, Schuh CA (2013) Transition from many domain to single domain martensite morphology in small-scale shape memory alloys. Acta Mater 61:5618–5625. doi:10.1016/j.actamat.2013.06.003 CrossRefGoogle Scholar
  6. 6.
    Dunand DC, Müllner P (2011) Size effects on magnetic actuation in Ni-Mn-Ga shape-memory alloys. Adv Mater 23:216–232CrossRefGoogle Scholar
  7. 7.
    Sutou Y, Omori T, Yamauchi K et al (2005) Effect of grain size and texture on pseudoelasticity in Cu–Al–Mn-based shape memory wire. Acta Mater 53:4121–4133. doi:10.1016/j.actamat.2005.05.013 CrossRefGoogle Scholar
  8. 8.
    San Juan J, Nó ML, Schuh CA (2008) Superelasticity and shape memory in micro- and nanometer-scale pillars. Adv Mater 20:272–278. doi:10.1002/adma.200701527 CrossRefGoogle Scholar
  9. 9.
    Waitz T, Kazykhanov V, Karnthaler HP (2004) Martensitic phase transformations in nanocrystalline NiTi studied by TEM. Acta Mater 52:137–147. doi:10.1016/j.actamat.2003.08.036 CrossRefGoogle Scholar
  10. 10.
    Waitz T, Antretter T, Fischer FD et al (2007) Size effects on the martensitic phase transformation of NiTi nanograins. J Mech Phys Solids 55:419–444. doi:10.1016/j.jmps.2006.06.006 CrossRefGoogle Scholar
  11. 11.
    Lovey FC, Chandrasekaran M (1982) Diffraction effects in β Cu-Zn and β-Cu-Zn-Al surface martensite transformation and microstructure. Le J Phys Colloq 43:C4–583. doi:10.1051/jphyscol:1982491 Google Scholar
  12. 12.
    Ortin J, Planes A (1988) Thermodynamic analysis of thermal measurements in thermoelastic martensitic transformations. Acta Metall 36:1873–1889CrossRefGoogle Scholar
  13. 13.
    Otsuka K, Wayman C (1999) Shape memory materials. Cambridge University Press, LondonGoogle Scholar
  14. 14.
    Ortĺn J, Delaey L (2002) Hysteresis in shape-memory alloys. Int J Non Linear Mech 37:1275–1281CrossRefGoogle Scholar
  15. 15.
    Wada K, Liu Y (2008) On the two-way shape memory behavior in NiTi alloy—an experimental analysis. Acta Mater 56:3266–3277. doi:10.1016/j.actamat.2008.03.005 CrossRefGoogle Scholar
  16. 16.
    Hamilton R, Sehitoglu H, Chumlyakov Y, Maier H (2004) Stress dependence of the hysteresis in single crystal NiTi alloys. Acta Mater 52:3383–3402. doi:10.1016/j.actamat.2004.03.038 CrossRefGoogle Scholar
  17. 17.
    Liu Y, Favier D, Orgeas L (2004) Mechanistic simulation of thermomechanical behaviour of thermoelastic martensitic transformations in polycrystalline shape memory alloys. J Phys 115:37–45. doi:10.1051/jp4 Google Scholar
  18. 18.
    Lovey FC, Torra V (1999) Shape memory in Cu-based alloys : phenomenological behavior at the mesoscale level and interaction of martensitic transformation with structural defects in Cu-Zn-Al. Prog Mater Sci 44:189–289CrossRefGoogle Scholar
  19. 19.
    Ma J, Karaman I, Noebe RD (2010) High temperature shape memory alloys. Int Mater Rev 55:257–315. doi:10.1179/095066010X12646898728363 CrossRefGoogle Scholar
  20. 20.
    Sugimoto K, Kamei K, Nakaniwa M (1990) Cu-Al-Ni-Mn: a new shape memory alloy for high temperature applications. Butterworth-Heinemann, OxfordGoogle Scholar
  21. 21.
    Wu M, Semiatin S, Schetky L (1994) Fabrication of a Cu-Al-Ni-Mn shape memory alloy. Mater Charact 246:343–348Google Scholar
  22. 22.
    Morris MA (1992) High temperature properties of ductile Cu-Al-Ni shape memory alloys with boron additions. Acta Metall Mater 40:1573–1586CrossRefGoogle Scholar
  23. 23.
    Segui C, Cesari E (1995) Ordering and stabilization in quenched CuAlNiMnB alloys. J Mater Sci 30:5770–5776. doi:10.1007/BF00356719 CrossRefGoogle Scholar
  24. 24.
    Chen L, Dunne D, Kennon N (1997) Determination of the parent grain orientation and habit plane normals for β′ 1 martensite in a Cu–Al–Ni–Mn shape memory alloy. J Mater Sci 2:3769–3773. doi:10.1023/A:1018671506278 CrossRefGoogle Scholar
  25. 25.
    Sutou Y, Omori T, Kainuma R et al (2002) Enhancement of Superelasticity in Cu-Al-Mn-Ni shape- memory alloys by texture control. Metall Mater Trans A 33:2817–2824CrossRefGoogle Scholar
  26. 26.
    Morris MA, Lipe T (1994) Microstructural influence of Mn additions on thermoelastic and pseudoelastic properties of Cu-Al-Ni alloys. Acta Metall Mater 42:1583–1594. doi:10.1016/0956-7151(94)90368-9 CrossRefGoogle Scholar
  27. 27.
    Ratchev P, Van Humbeeck J, Delaey L (1993) On the formation of 2H stacking sequence in 18R martensite plates in a precipitate containing Cu-Al-Ni-Ti-Mn alloy. Acta Metall Mater 41:2441–2449CrossRefGoogle Scholar
  28. 28.
    Omori T, Koeda N, Sutou Y et al (2007) Superplasticity of Cu-Al-Mn-Ni shape memory alloy. Mater Trans 48:2914–2918. doi:10.2320/matertrans.D-MRA2007879 CrossRefGoogle Scholar
  29. 29.
    Patoor E, Supe Z, Ge D et al (1995) Micromechanical modelling of the superelastic behavior. Le J Phys. 5:C2Google Scholar
  30. 30.
    Bhattacharya K (2003) Microstructure of Martensite: why it forms and how it gives rise to the shape-memory effect. Oxford University Press, OxfordGoogle Scholar
  31. 31.
    Patoor E, Lagoudas DC, Entchev PB et al (2006) Shape memory alloys, Part I: general properties and modeling of single crystals. Mech Mater 38:391–429. doi:10.1016/j.mechmat.2005.05.027 CrossRefGoogle Scholar
  32. 32.
    Jung Y, Papadopoulos P, Ritchie RO (2004) Constitutive modelling and numerical simulation of multivariant phase transformation in superelastic shape-memory alloys. Int J Numer Methods Eng 60:429–460. doi:10.1002/nme.940 CrossRefGoogle Scholar
  33. 33.
    Thamburaja P, Anand L (2001) Polycrystalline shape-memory materials: effect of crystallographic texture. J Mech Phys Solids 49:709–737. doi:10.1016/S0022-5096(00)00061-2 CrossRefGoogle Scholar
  34. 34.
    Gao X, Brinson L (2002) A simplified multivariant SMA model based on invariant plane nature of martensitic transformation. J Intell Mater Syst Struct 13:795–810. doi:10.1177/104538902032786 CrossRefGoogle Scholar
  35. 35.
    Wollants P, Roos JR, Delaey L (1993) Thermally- and stress-induced thermoelastic martensitic transformations in the reference frame of equilibrium thermodynamics. Prog Mater Sci 37:227–288. doi:10.1016/0079-6425(93)90005-6 CrossRefGoogle Scholar
  36. 36.
    San Juan J, Nó ML, Schuh CA (2009) Nanoscale shape-memory alloys for ultrahigh mechanical damping. Nat Nanotechnol 4:415–419. doi:10.1038/nnano.2009.142 CrossRefGoogle Scholar
  37. 37.
    Salzbrenner R, Cohen M (1979) On the thermodynamics of thermoelastic martensitic transformations. Acta Metall 27:739–748CrossRefGoogle Scholar
  38. 38.
    Romero R, Pelegrina JL (2003) Change of entropy in the martensitic transformation and its dependence in Cu-based shape memory alloys. Mater Sci Eng A 354:243–250. doi:10.1016/S0921-5093(03)00013-3 CrossRefGoogle Scholar
  39. 39.
    Saburi T, Wayman C (1979) Crystallographic similarities in shape memory martensites. Acta Metall 27:979–995. doi:10.1016/0001-6160(79)90186-X CrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2015

Authors and Affiliations

  • Nihan Tuncer
    • 1
  • Lei Qiao
    • 2
  • Raul Radovitzky
    • 2
  • Christopher A. Schuh
    • 1
  1. 1.Department of Materials Science and EngineeringMassachusetts Institute of TechnologyCambridgeUSA
  2. 2.Department of Aeronautics and AstronauticsMassachusetts Institute of TechnologyCambridgeUSA

Personalised recommendations