Two internal-friction peaks related to thermoelastic martensitic transformations inCuAlNiMnTishape-memory alloy

This paper is concerned with the application of fundamental thermodynamic theories in the analysis of thermoelastic martensitic transformations in shape memory alloys, with a particular reference to polycrystalline NiTi. The discussion is delivered in two parts. The first part presents a concise overview of the fundamental theories of thermodynamics of thermoelastic martensitic transformations established in the past 30 years. The second part focuses on the principles governing the application of the theories, interpretation of the thermodynamic parameters defined in the theories, experimental determination of the parameters, and some common misperceptions and unjustified assumptions in practice concerning these parameters.

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On the thermodynamics of thermoelastic martensitic transformations

Acta Metallurgica ◽

10.1016/0001-6160(79)90107-x ◽

1979 ◽

Vol 27 (5) ◽

pp. 739-748 ◽

Cited By ~ 293

Author(s):

R.J. Salzbrenner ◽

Morris Cohen

Keyword(s):

Martensitic Transformations ◽

Thermoelastic Martensitic Transformations

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Thermoelastic martensitic transformations in ternary Ni50Mn50–z Ga z alloys

Technical Physics Letters ◽

10.1134/s106378501601017x ◽

2016 ◽

Vol 42 (1) ◽

pp. 75-78 ◽

Cited By ~ 1

Author(s):

E. S. Belosludtseva ◽

N. N. Kuranova ◽

E. B. Marchenkova ◽

A. G. Popov ◽

V. G. Pushin

Keyword(s):

Martensitic Transformations ◽

Thermoelastic Martensitic Transformations

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Internal Friction and Dynamic Modulus in Ultra-High Temperature Ru-Nb Functional Intermetallics / Tarcie Wewnętrzne I Moduł Dynamiczny W Bardzo Wysoko Temperaturowych Funkcjonalnych Związkach Międzymetalicznych Z Układu Ru-Nb

Archives of Metallurgy and Materials ◽

10.1515/amm-2015-0490 ◽

2015 ◽

Vol 60 (4) ◽

pp. 3069-3072

Author(s):

M.L. Nó ◽

L. Dirand ◽

A. Denquin ◽

J. San Juan

Keyword(s):

High Temperature ◽

Internal Friction ◽

Martensitic Transformations ◽

Time Dependent ◽

Structural Defects ◽

Complete Analysis ◽

Internal Friction Peak ◽

Thermally Activated ◽

Temperature Ranges ◽

Lower Temperature

In the present work we have studied the high-temperature shape memory alloys based on the Ru-Nb system by using two mechanical spectrometers working in temperature ranges from 200 to 1450ºC and -150 to 900ºC. We have studied internal friction peaks linked to the martensitic transformations in the range from 300 to 1200ºC. In addition, we have evidenced another internal friction peak at lower temperature than the transformations peaks, which apparently exhibits the behaviour of a thermally activated relaxation peak, but in fact is a strongly time-dependent peak. We have carefully studied this peak and discussed its microscopic origin, concluding that it is related to the interaction of some structural defects with martensite interfaces. Finally, we perform a complete analysis of the whole internal friction spectrum, taking into account the possible relationship between the time-dependent peak and the martensitic transformation behaviour.

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