Jerky elasticity: Avalanches and the martensitic transition in Cu74.08Al23.13Be2.79 shape-memory alloy

TL;DR

This study investigates jerky elasticity in a Cu-Al-Be shape-memory alloy, revealing avalanche behavior during phase transformation and confirming criticality predictions through elastic response measurements.

Contribution

It demonstrates the observation of avalanche criticality in elastic measurements of a shape-memory alloy, aligning with acoustic emission findings and advancing understanding of martensitic transformations.

Findings

Avalanche statistics follow power-law distribution.

Elastic dissipation spikes correspond to phase transformation avalanches.

Results align with previous acoustic emission studies.

Abstract

Jerky elasticity was observed by dynamical mechanical analyzer measurements in a single crystal of the shape memory alloy Cu74.08Al23.13Be2.79. Jerks appear as spikes in the dissipation of the elastic response function and relate to the formation of avalanches during the transformation between the austenite and the martensite phase. The statistics of the avalanches follows the predictions of avalanche criticality P(E) proportional to E-epsilon where P(E) is the probability of finding an avalanche with the energy E. This result reproduces, within experimental uncertainties, previous findings by acoustic emission techniques.