Modeling of NiTiHf using finite difference method

Nazanin Farjam, Reza Mehrabi, Haluk Karaca, Reza Mirzaeifar, Mohammad Elahinia

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review


NiTiHf is a high temperature and high strength shape memory alloy with transformation temperatures above 100oC. A constitutive model based on Gibbs free energy is developed to predict the behavior of this material. Two different irrecoverable strains including transformation induced plastic strain (TRIP) and viscoplastic strain (VP) are considered when using high temperature shape memory alloys (HTSMAs). The first one happens during transformation at high levels of stress and the second one is related to the creep which is rate-dependent. The developed model is implemented for NiTiHf under uniaxial loading. Finite difference method is utilized to solve the proposed equations. The material parameters in the equations are calibrated from experimental data. Simulation results are captured to investigate the superelastic behavior of NiTiHf. The extracted results are compared with experimental tests of isobaric heating and cooling at different levels of stress and also superelastic tests at different levels of temperature. More results are generated to investigate the capability of the proposed model in the prediction of the irrecoverable strain after full transformation in HTSMAs.

Original languageEnglish
Title of host publicationBehavior and Mechanics of Multifunctional Materials and Composites XII
EditorsHani E. Naguib
ISBN (Electronic)9781510616882
StatePublished - 2018
EventBehavior and Mechanics of Multifunctional Materials and Composites XII 2018 - Denver, United States
Duration: Mar 5 2018Mar 8 2018

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
ISSN (Print)0277-786X
ISSN (Electronic)1996-756X


ConferenceBehavior and Mechanics of Multifunctional Materials and Composites XII 2018
Country/TerritoryUnited States

Bibliographical note

Publisher Copyright:
© 2018 SPIE.


  • Analytical solution
  • Finite difference method
  • High temeperature shape memory alloys
  • NiTiHf
  • Uniaxial loading

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering


Dive into the research topics of 'Modeling of NiTiHf using finite difference method'. Together they form a unique fingerprint.

Cite this