Recent topics on metastability, hysteresis, avalanches, and acoustic emission associated to martensitic transitions in functional materials

TL;DR

This paper reviews recent theoretical and experimental advances in understanding metastability, hysteresis, and avalanches during martensitic and other first-order phase transitions in functional materials, emphasizing acoustic emission phenomena.

Contribution

It provides a comprehensive overview of simple models for athermal phase transition dynamics and connects them with recent experimental findings on acoustic emission avalanches.

Findings

First-order phase transitions proceed via avalanches.

Theoretical models capture metastability and hysteresis.

Experimental evidence shows acoustic emission avalanches during structural transitions.

Abstract

We review some results for the dynamics of first-order phase transitions in functional materials. We especially focus on simple models of athermal evolution in driven ferromagnets that give a global picture of metastability and hysteresis, showing that first-order phase transitions in such systems proceed by avalanches. Within this theoretical framework, we then discuss recent experiments on acoustic emission avalanches in structural phase transitions.