Mechanical response of NiFeGa alloys containing second-phase particles
نویسندگان
چکیده
Tensile and compressive strain–temperature and stress–strain responses have been used for the first time to investigate the effects of second-phase particles on the deformation of NiFeGa shape memory alloys. Particles are conducive to the dissipation of stored energy; stress and thermal hysteresis increase three-fold in aged alloys. Although dissipation is severe, recoverable strain levels are as large as +12% and 6%, which match strains for the unaged alloys. These results demonstrate that second-phase particles can be used to tailor the hysteresis while maintaining large transformation strains. 2007 Published by Elsevier Ltd. on behalf of Acta Materialia Inc.
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