An analysis of non-classical austenite-martensite interfaces in CuAlNi

TL;DR

This paper analyzes non-classical austenite-martensite interfaces in CuAlNi, demonstrating they can be modeled with non-linear elasticity and providing predictions on variant volume fractions and habit plane orientations.

Contribution

It extends the theoretical framework to describe recently observed interfaces in CuAlNi, linking experimental observations with non-linear elasticity models.

Findings

Interfaces can be described by non-linear elasticity models.

Predictions made for volume fractions of martensitic variants.

Habit plane normals are characterized for CuAlNi interfaces.

Abstract

Ball and Carstensen theoretically investigated the possibility of the occurrence of non-classical austenite-martensite interfaces and studied the cubic-to-tetragonal case extensively. Here, we aim to present an analysis of such interfaces recently observed by Seiner et al. in CuAlNi single crystals, undergoing a cubic-to-orthorhombic transition. We show that they can be described by the non-linear elasticity model for martensitic transformations and we make some predictions regarding the volume fractions of the martensitic variants involved, as well as the habit plane normals.