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Shape Memory Characteristics of Ti(sub 49.5)Ni(sub 25)Pd(sub 25)Sc(sub 0.5) High-Temperature Shape Memory Alloy After Severe Plastic DeformationA Ti(49.5)Ni25Pd25Sc(0.5) high-temperature shape memory alloy is thermomechanically processed to obtain enhanced shape-memory characteristics: in particular, dimensional stability upon repeated thermal cycles under constant loads. This is accomplished using severe plastic deformation via equal channel angular extrusion (ECAE) and post-processing annealing heat treatments. The results of the thermomechanical experiments reveal that the processed materials display enhanced shape memory response, exhibiting higher recoverable transformation and reduced irrecoverable strain levels upon thermal cycling compared with the unprocessed material. This improvement is attributed to the increased strength and resistance of the material against defect generation upon phase transformation as a result of the microstructural refinement due to the ECAE process, as supported by the electron microscopy observations.
Document ID
20110016166
Document Type
Reprint (Version printed in journal)
Authors
Atli, K. C. (Texas A&M Univ. College Station, TX, United States)
Karaman, I. (Texas A&M Univ. College Station, TX, United States)
Noebe, R. D. (NASA Glenn Research Center Cleveland, OH, United States)
Garg, A. (NASA Glenn Research Center Cleveland, OH, United States)
Chumlyakov, Y. I. (Tomsk State Univ. Tomsk, Russian Federation)
Kireeva, I. V. (Tomsk State Univ. Tomsk, Russian Federation)
Date Acquired
August 25, 2013
Publication Date
July 1, 2011
Publication Information
Publication: Acta Materialla
Volume: 59
Issue: 12
ISSN: 1359-6454
Subject Category
Mechanical Engineering
Report/Patent Number
E-17919
Funding Number(s)
CONTRACT_GRANT: NNX07AB56A
WBS: WBS 561581.02.08.03.15.136
Distribution Limits
Public
Copyright
Other