Role of severe plastic deformation on the cyclic reversibility of a Ti50.3Ni33.7Pd16 high temperature shape memory alloy

KOÇKAR B., Atli K. C., Ma J., Haouaoui M., Karaman I., Nagasako M., ...Daha Fazla

ACTA MATERIALIA, cilt.58, sa.19, ss.6411-6420, 2010 (SCI-Expanded) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 58 Sayı: 19
  • Basım Tarihi: 2010
  • Doi Numarası: 10.1016/j.actamat.2010.08.003
  • Dergi Adı: ACTA MATERIALIA
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Sayfa Sayıları: ss.6411-6420
  • Hacettepe Üniversitesi Adresli: Hayır

Özet

The present work focuses on the effect of microstructural refinement on the thermo-mechanical cyclic stability of a Ti50.3Ni33.7Pd16 high temperature shape memory alloy (HTSMA) which was severe plastically deformed using equal channel angular extrusion (ECAE). The grain/subgrain size of the high temperature austenite phase was refined down to about 100 nm, the lowest reported to date in HTSMAs. The increase in strength differential between the onset of transformation and the macroscopic plastic yielding after ECAE led to a notable enhancement in the cyclic stability during isobaric cooling heating experiments. The reduction in irrecoverable strain levels was attributed to the increase in critical stress for dislocation slip due to the microstructural refinement during the ECAE process. (C) 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.