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arXiv · 1509.02477

Observation of the two way shape memory effect in an atomistic model of martensitic transformation

E. A. Jagla
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Abstract

We study a system of classical particles in two dimensions interacting through an isotropic pair potential that displays a martensitic phase transition between a triangular and a rhomboidal structure upon the change of a single parameter. Previously it was shown that this potential is able to reproduce the shape memory effect and super-elasticity, among other well known features of the phenomenology of martensites. Here we extend those previous studies and describe the development of the more subtle two-way shape memory effect. We show that in a poly-crystalline sample, the effect can be associated to the existence of retained martensite within the austenite phase. We also study the case of a single crystal sample where the effect is associated to particular orientations of the dislocations, either induced by training or by an ad hoc construction of a starting sample.

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E. A. Jagla. 2015-09-08. Observation of the two way shape memory effect in an atomistic model of martensitic transformation. https://arxiv.org/abs/1509.02477

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