Hysteresis in a system driven by either generalized force or displacement variables

TL;DR

This study compares hysteresis behaviors in a Cu-Zn-Al single crystal under strain-driven and stress-driven conditions, revealing significant differences in loop shape, energy dissipation, and re-entrant behavior, with experimental results aligning with recent models.

Contribution

It provides the first direct experimental comparison of hysteresis in a shape memory alloy under different driving conditions, highlighting key differences and validating recent theoretical models.

Findings

Strain-driven hysteresis loops show re-entrant behavior not seen in stress-driven loops.

Energy dissipation is higher in stress-driven experiments.

Experimental results qualitatively agree with recent theoretical models.

Abstract

We report on experiments aimed at comparing the hysteretic response of a Cu-Zn-Al single crystal undergoing a martensitic transition under strain-driven and stress-driven conditions. Strain-driven experiments were performed using a conventional tensile machine while a special device was designed to perform stress-driven experiments. Significant differences in the hysteresis loops were found. The strain-driven curves show re-entrant behaviour (yield point) which is not observed in the stress-driven case. The dissipated energy in the stress-driven curves is larger than in the strain-driven ones. Results from recently proposed models qualitatively agree with experiments.