Structure and phase transformations in copper-alloyed rapidly melt-quenched Ni50Ti32Hf18-based alloys with high-temperature shape memory effect

Au-50%Cu (at. %) alloy presents the shape memory effect (SME), which is dependent of the solid state transformation that happens during heating, after the introduction of an internal stress in the quenched state. The solid state phase transformation temperatures were determined by means of Differential Thermal Analysis (DTA), both in heating and cooling cycles. With the obtained DTA results, a sequence of high temperature X-ray diffraction (XRD) experiments were made, in order to confirm the presence of the solid state phase transformations and to determine their stable crystal structure and lattice parameters. These XRD results were compared with those obtained from the literature. The displacements of the lattice parameters were determined, for each equilibrium phase, for measurements at room temperature and at high temperature. The characteristics of the quenched samples were also studied in order to determine the phase transformations that are responsible for the shape memory effect in this alloy.

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Effect of aging on transformation behavior and shape memory effect of a CuAlNb high temperature shape memory alloy

Journal of Materials Science ◽

10.1007/s10853-006-0573-y ◽

2006 ◽

Vol 41 (18) ◽

pp. 6165-6167 ◽

Cited By ~ 2

Author(s):

Z. Y. Gao ◽

Y. Wu ◽

Y. X. Tong ◽

W. Cai ◽

Y. F. Zheng ◽

...

Keyword(s):

High Temperature ◽

Shape Memory Alloy ◽

Shape Memory ◽

Shape Memory Effect ◽

Memory Effect ◽

Transformation Behavior

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Two way shape memory effect in NiTiHf high temperature shape memory alloy tubes

Acta Materialia ◽

10.1016/j.actamat.2018.09.058 ◽

2019 ◽

Vol 163 ◽

pp. 1-13 ◽

Cited By ~ 20

Author(s):

C. Hayrettin ◽

O. Karakoc ◽

I. Karaman ◽

J.H. Mabe ◽

R. Santamarta ◽

...

Keyword(s):

High Temperature ◽

Shape Memory Alloy ◽

Shape Memory ◽

Shape Memory Effect ◽

Memory Effect

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Giant two-way shape memory effect in high-temperature Ni–Mn–Ga single crystal

Physics Procedia ◽

10.1016/j.phpro.2010.11.081 ◽

2010 ◽

Vol 10 ◽

pp. 94-98 ◽

Cited By ~ 15

Author(s):

V.A. Chernenko ◽

E. Villa ◽

S. Besseghini ◽

J.M. Barandiaran

Keyword(s):

High Temperature ◽

Single Crystal ◽

Shape Memory ◽

Shape Memory Effect ◽

Memory Effect

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The Concept of Physical Metric in the Thermomechanical Modeling of Phase Transformations With Emphasis on Shape Memory Alloy Materials

Journal of Engineering Materials and Technology ◽

10.1115/1.4023780 ◽

2013 ◽

Vol 135 (2) ◽

Cited By ~ 3

Author(s):

Vassilis P. Panoskaltsis ◽

Lazaros C. Polymenakos ◽

Dimitris Soldatos

Keyword(s):

Shape Memory Alloy ◽

Shape Memory ◽

Phase Transformations ◽

Shape Memory Effect ◽

Memory Effect ◽

Material Model ◽

Internal Variable ◽

Theoretical Interest ◽

Numerical Examples ◽

Thermomechanical Modeling

In this work we derive a new version of generalized plasticity, suitable to describe phase transformations. In particular, we present a general multi surface formulation of the theory which is capable of describing the multiple and interacting loading mechanisms, which occur during phase transformations. The formulation relies crucially on the consideration of the intrinsic material (“physical”) metric as a primary internal variable and does not invoke any decomposition of the kinematical quantities into elastic and inelastic (transformation induced) parts. The new theory, besides its theoretical interest, is also important for application purposes such as the description and the prediction of the response of shape memory alloy materials. This is shown in the simplest possible setting by the introduction of a material model. The ability of the model in simulating several patterns of the experimentally observed behavior of these materials such as the pseudoelastic phenomenon and the shape memory effect is assessed by representative numerical examples.

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