Shape memory materials

A Thermodynamical Constitutive Model for Shape Memory Materials. Part I. the Monolithic Shape Memory Alloy

Pseudoelasticity and the shape memory e ect (SME) due to martensitic transformation and reorientation of polycrystalline shape memory alloy (SMA) materials are modelled using a free energy function and a dissipation potential. Three di erent cases are considered, based on the number of internal state variables in the free energy: (1) Austenite plus a variable number of martensite variants; (2) ...

Controlling the martensitic transition in Heusler shape-memory materials

A Viewpoint on: Role of Electronic Structure in the Martensitic Phase Transition of Ni2Mn1+xSn1−x Studied by Hard-X-Ray Photoelectron Spectroscopy and Ab Initio Calculation M. Ye, A. Kimura, Y. Miura, M. Shirai, Y. T. Cui, K. Shimada, H. Namatame, M. Taniguchi, S. Ueda, K. Kobayashi, R. Kainuma, T. Shishido, K. Fukushima and T. Kanomata Phys. Rev. Lett. 104, 176401 (2010) – Published April 26, ...

NiTi Shape Memory Alloys, Promising Materials in Orthopedic Applications

Modeling Permanent Deformations of Superelastic and Shape Memory Materials

In this paper we propose a modification of the polycrystalline shape memory alloy constitutive model originally proposed by Souza. By introducing a transformation strain energy with two different hardening coefficients, we are able to take into account the effect of the martensitic transformation of unfavorably oriented grains occurring after the main plateau. By choosing a proper second harden...

Polymeric triple-shape materials.

Shape-memory polymers represent a promising class of materials that can move from one shape to another in response to a stimulus such as heat. Thus far, these systems are dual-shape materials. Here, we report a triple-shape polymer able to change from a first shape (A) to a second shape (B) and from there to a third shape (C). Shapes B and C are recalled by subsequent temperature increases. Whe...