Origin of stabilization of macrotwin boundaries in martensites

TL;DR

This paper explains the stabilization of complex microstructures along macrotwin boundaries in martensites by comparing nonlinear and linearized Ginzburg-Landau models, emphasizing the importance of geometric nonlinearity.

Contribution

It demonstrates that only the geometrically nonlinear Ginzburg-Landau model accurately reproduces experimental observations of martensite microstructures.

Findings

Linearized model fails to capture boundary stabilization effects.

Geometrically nonlinear model aligns with experimental data.

Nonlinear theory is essential for accurate microstructure modeling.

Abstract

The origin of stabilization of complex microstructures along macrotwin boundaries in martensites is explained by comparing two models based on Ginzburg-Landau theory. The first model incorporates a geometrically nonlinear strain tensor to ensure that the Landau energy is invariant under rigid body rotations, while the second model uses a linearized strain tensor under the assumption that deformations and rotations are small. We show that the approximation in the second model does not always hold for martensites and that the experimental observations along macrotwin boundaries can only be reproduced by the geometrically nonlinear (exact) theory.