Effective dimensionality of the Portevin - Le Chatelier effect

TL;DR

This paper investigates the Portevin-Le Chatelier effect in Al-Mg alloys, revealing that its dynamics are governed by a finite number of degrees of freedom that decrease as strain increases, based on experimental stress data analysis.

Contribution

It introduces a method to determine the effective dimensionality of the PLC effect from experimental data, showing its reduction with increased strain.

Findings

The PLC effect exhibits finite-dimensional dynamics.

Effective dimension decreases with strain.

Stress time series analysis reveals underlying degrees of freedom.

Abstract

Tensile tests have been carried out by deforming polycrystalline samples of substitutional Al-2.5%Mg alloy at room temperature at a range of strain rates. The Portevin - Le Chatelier (PLC) effect was observed. From an analysis of the experimental stress versus time series data we have inferred that the dynamics of the PLC effect in a local finite time is controlled by a finite number of degrees of freedom and this effective dimension becomes reduced with increasing strain.