Shape Memory and Superelasticity

, Volume 5, Issue 1, pp 113–124 | Cite as

Additive Manufacturing of Ni-Rich NiTiHf20: Manufacturability, Composition, Density, and Transformation Behavior

  • M. Nematollahi
  • G. Toker
  • S. E. Saghaian
  • J. Salazar
  • M. Mahtabi
  • O. Benafan
  • H. Karaca
  • M. ElahiniaEmail author


In this work, the effects of process parameters on the fabrication of NiTiHf alloys using selective laser melting are studied. Specimens were printed using bidirectional scanning pattern and with various sets of process parameters of laser power (100–250 W), hatch spacing (60–140 µm), and scanning speed (200–1000 mm/s). Cracking and delamination formation, dimensional accuracy, density, and transformation temperatures were examined. Despite the brittle nature of the alloy, fully dense parts have been produced. Laser scanning speed and volumetric energy density were found to be the most influential process parameters on fabricating defect-free samples. It was shown that transformation temperatures are highly dependent on the process parameters. By proper choice of parameters, it is possible to tailor the austenite finish temperature from 100 to 400 °C. The most influential factors on transformation behavior were found to be the laser power and energy density. It is worth noting that these two parameters at higher levels resulted in high process temperatures and therefore a larger level of Ni evaporation. Among the four parameters that constitute the energy density, the hatch spacing does not significantly affect the transformation temperatures. These findings serve as the foundation of developing HTSMA devices with desired geometrical and functional properties.


NiTiHf Additive manufacturing Selective laser melting High-temperature shape memory alloys (HTSMAs) Thermal cycling Transformation temperatures 



The authors would like to acknowledge the financial support of Ohio Federal Research Network. O.B. acknowledges support from the NASA Transformational Tools and Technologies (TTT) project.


  1. 1.
    Ma J, Karaman I, Noebe RD (2010) High temperature shape memory alloys. Int Mater Rev 55(5):257–315CrossRefGoogle Scholar
  2. 2.
    Mohd J, Leary M, Subic A, Gibson MA (2014) A review of shape memory alloy research, applications and opportunities. Mater Des 56:1078–1113CrossRefGoogle Scholar
  3. 3.
    Karaca HE, Acar E, Tobe H, Saghaian SM (2014) NiTiHf-based shape memory alloys. Mater Sci Technol 30(13):1530–1544CrossRefGoogle Scholar
  4. 4.
    Angst DR, Thoma PE, Kao MY (1995) The effect of hafnium content on the transformation temperatures of Ni49Ti51-xHfx. Shape memory alloys. J Phys IV 5(C8):C8–747Google Scholar
  5. 5.
    Canadinc D, Trehern W, Ozcan H, Hayrettin C, Karakoc O, Karaman I, Sun F, Chaudhry Z (2017) On the deformation response and cyclic stability of Ni50Ti35Hf15 high temperature shape memory alloy wires. Scr Mater 135:92–96CrossRefGoogle Scholar
  6. 6.
    Elahinia M, Shayesteh N, Amerinatanzi A, Saedi S, Toker GP, Karaca H, Bigelow GS, Benafan O (2018) Additive manufacturing of NiTiHf high temperature shape memory alloy. Scr Mater 145:90–94CrossRefGoogle Scholar
  7. 7.
    Benafan O, Bigelow GS, Scheiman DA (2018) Transformation behavior in NiTi-20Hf shape memory alloys—transformation temperatures and hardness. Scr Mater 146:251–254CrossRefGoogle Scholar
  8. 8.
    Coughlin DR, Phillips PJ, Bigelow GS, Garg A, Noebe RD, Mills MJ (2012) Characterization of the microstructure and mechanical properties of a 50.3Ni-29.7Ti-20Hf shape memory alloy. Scr Mater 67(1):112–115CrossRefGoogle Scholar
  9. 9.
    Benafan O, Bigelow GS, Garg A, Noebe RD (2019) Viable low temperature shape memory alloys based on Ni-Ti-Hf formulations. Scr Mater 164:115–120CrossRefGoogle Scholar
  10. 10.
    Elahinia M, Hashemi M, Tabesh M, Bhaduri SB (2012) Manufacturing and processing of NiTi implants: a review. Prog Mater Sci 57(5):911–946CrossRefGoogle Scholar
  11. 11.
    Biermann D, Kahleyss F, Krebs E, Upmeier T (2011) A study on micro-machining technology for the machining of NiTi: five-axis micro-milling and micro deep-hole drilling. J Mater Eng Perform 20(4–5):745–751CrossRefGoogle Scholar
  12. 12.
    Wu MH (2002) Fabrication of nitinol materials and components. Mater Sci Forum 394–395:285–292CrossRefGoogle Scholar
  13. 13.
    Elahinia M, Moghaddam NS, Andani MT, Amerinatanzi A, Bimber BA, Hamilton RF (2016) Fabrication of NiTi through additive manufacturing: a review. Prog Mater Sci 83:630–663CrossRefGoogle Scholar
  14. 14.
    Dadbakhsh S, Speirs M, Kruth JP, Schrooten J, Luyten J, Van Humbeeck J (2014) Effect of SLM parameters on transformation temperatures of shape memory nickel titanium parts. Adv Eng Mater 16(9):1140–1146CrossRefGoogle Scholar
  15. 15.
    Speirs M, Wang X, Van Baelen S, Ahadi A, Dadbakhsh S, Kruth JP, Van Humbeeck J (2016) On the transformation behavior of NiTi shape-memory alloy produced by SLM. Shape Mem Superelast 2(4):310–316CrossRefGoogle Scholar
  16. 16.
    Bormann T, Schumacher R, Mertmann M, de Wild M (2012) Tailoring selective laser melting process parameters for NiTi implants. J Mater Eng Perform 21(December):2519–2524CrossRefGoogle Scholar
  17. 17.
    Saedi S, Moghaddam NS, Amerinatanzi A, Elahinia M, Karaca HE (2018) On the effects of selective laser melting process parameters on microstructure and thermomechanical response of Ni-rich NiTi. Acta Mater 144:552–560CrossRefGoogle Scholar
  18. 18.
    Benafan O, Gaydosh DJ (2017) High temperature shape memory alloy Ni50.3Ti29.7Hf20 torque tube actuators. Smart Mater Struct 26(9):095002CrossRefGoogle Scholar
  19. 19.
    Bigelow GS, Garg A, Padula SA, Gaydosh DJ, Noebe RD (2011) Load-biased shape-memory and superelastic properties of a precipitation strengthened high-temperature Ni50.3Ti29.7Hf20alloy. Scr Mater 64(8):725–728CrossRefGoogle Scholar
  20. 20.
    Haberland C, Elahinia M, Walker J, Meier H (2013) Visions, concepts and strategies for smart nitinol actuators and complex nitinol structures produced by additive manufacturing. In: ASME 2013 conference on smart materials, adaptive structures and intelligent systems, p V001T01A006Google Scholar
  21. 21.
    American Society for Testing and Materials (2004) Standard test method for transformation temperature of nickel-titanium alloys by thermal analysis. American Society for Testing and Materials, vol ASTM F2004, pp 10–13Google Scholar
  22. 22.
    Zhang B, Li Y, Bai Q (2017) Defect formation mechanisms in selective laser melting: a review. Chin J Mech Eng 30(3):515–527CrossRefGoogle Scholar
  23. 23.
    Gong H, Rafi K, Gu H, Starr T, Stucker B (2014) Analysis of defect generation in Ti-6Al-4V parts made using powder bed fusion additive manufacturing processes. Addit Manuf 1–4:87–98CrossRefGoogle Scholar
  24. 24.
    Grasso M, Colosimo BM (2017) Process defects and in situ monitoring methods in metal powder bed fusion: a review. Meas Sci Technol 28(4):44005CrossRefGoogle Scholar
  25. 25.
    Speirs M, Dadbakhsh S, Buls S, Kruth JP, Van Humbeeck J, Schrooten J, Luyten J (2013) The effect of SLM parameters on geometrical characteristics of open porous NiTi scaffolds. In: High value manufacturing: advanced research in virtual and rapid prototyping: proceedings of the 6th international conference on advanced research in virtual and rapid prototypingGoogle Scholar
  26. 26.
    Walker JM, Haberland C, Andani MT, Karaca HE, Dean D, Elahinia M (2016) Process development and characterization of additively manufactured nickel-titanium shape memory parts. J Intell Mater Syst Struct 27(19):2653–2660CrossRefGoogle Scholar
  27. 27.
    Mahmoudi M, Tapia G, Franco B, Ma J, Arroyave R, Karaman I, Elwany A (2018) On the printability and transformation behavior of nickel-titanium shape memory alloys fabricated using laser powder-bed fusion additive manufacturing. J Manf Process 35(August):672–680CrossRefGoogle Scholar
  28. 28.
    Haberland C, Elahinia M, Walker J, Meier J, Frenzel J (2013) Additive manufacturing of shape memory devices and pseudoelastic components. In: ASME 2013 conference on smart materials, adaptive structures and intelligent systems, p V001T01A005Google Scholar
  29. 29.
    Frenzel J, George EP, Dlouhy A, Somsen C, Wagner MF, Eggeler G (2010) Influence of Ni on martensitic phase transformations in NiTi shape memory alloys. Acta Mater 58(9):3444–3458CrossRefGoogle Scholar
  30. 30.
    David NAII, Thoma PE, Kao M-Y, Angst DR (1992) High transformation temperature shape memory alloy. Google Patents, 19-May-1992Google Scholar
  31. 31.
    Scipioni U, Wolfer AJ, Matthews MJ, Delplanque JR, Schoenung JM (2017) On the limitations of volumetric energy density as a design parameter for selective laser melting. JMADE 113:331–340Google Scholar
  32. 32.
    Rashid R, Masood SH, Ruan D, Palanisamy S, Rashid RAR, Brandt M (2017) Effect of scan strategy on density and metallurgical properties of 17-4PH parts printed by selective laser melting (SLM). J Mater Process Technol 249(February):502–511CrossRefGoogle Scholar
  33. 33.
    Gu H, Gong H (2013) Influences of energy density on porosity and microstructure of selective laser melted 17-4PH stainless steel. In: 24th international SFF symposium—an additive manufacturing conference, SFF 2013Google Scholar
  34. 34.
    Li R, Liu J, Shi Y, Wang L (2012) Balling behavior of stainless steel and nickel powder during selective laser melting process. Int J Adv Manuf Tech 59:1025–1035CrossRefGoogle Scholar
  35. 35.
    Patterson AE, Messimer SL, Farrington PA (2017) Overhanging features and the SLM/DMLS residual stresses problem: review and future research need. Technologies 5(2):15CrossRefGoogle Scholar
  36. 36.
    Saghaian SM, Karaca HE, Tobe H, Pons J, Santamarta R, Chumlyakov YI, Noebe RD (2016) Effects of Ni content on the shape memory properties and microstructure of Ni-rich NiTi-20Hf alloys. Smart Mater Struct 25(9):95029CrossRefGoogle Scholar

Copyright information

© ASM International 2019

Authors and Affiliations

  • M. Nematollahi
    • 1
  • G. Toker
    • 2
  • S. E. Saghaian
    • 2
  • J. Salazar
    • 1
  • M. Mahtabi
    • 3
  • O. Benafan
    • 4
  • H. Karaca
    • 2
  • M. Elahinia
    • 1
    Email author
  1. 1.Dynamic and Smart Systems Laboratory, Mechanical Industrial and Manufacturing Engineering DepartmentThe University of ToledoToledoUSA
  2. 2.Department of Mechanical EngineeringUniversity of KentuckyLexingtonUSA
  3. 3.Department of Mechanical EngineeringUniversity of Tennessee at ChattanoogaChattanoogaUSA
  4. 4.Materials and Structures DivisionNASA Glenn Research CenterClevelandUSA

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