Internal friction of B2→B19′ martensitic transformation of Ti50Ni50 shape memory alloy under isothermal conditions

MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING

卷:454

Article

Chang, S. H. ; Wu, S. K.

关键词: TiNi shape memory alloy;    martensitic transformation;    internal friction;    dynamic mechanical analysis;   

DOI  :  10.1016/j.msea.2006.11.157

来源: Elsevier

【 摘 要 】

The inherent internal friction (IFPT + IFI)(B2)->(B19') of cold-rolled and annealed Ti50Ni50 alloy that exhibits B2 -> B19' martensitic transformation is studied under isothermal conditions. The tan delta value of (IFPT + IFI)(B2 -> B19') is proportional to sigma(0)/nu(1/2) and its damping mechanism is thus related to stress-assisted martensitic transformation and stress-assisted motion of twin boundaries. The tan delta value of (IFPT + IFI)(B2 -> B19') is smaller than those of (IFPT + IFI)(B2 -> R) and (IFPT + IFI)(R -> B19)' because the former shows no R-phase. The obliterated dislocations and defects after sufficient annealing can lower the tan 3 value of the relaxation peak at about -60 degrees C. (c) 2006 Elsevier B.V. All rights reserved.

【 授权许可】

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