Thermal dissipation as both the strength and weakness of matter. A material failure prediction by monitoring creep

TL;DR

This paper presents a thermally activated model that predicts material failure by monitoring creep, revealing how thermal effects influence both the strength and weakness of solids across various materials.

Contribution

It introduces a novel method to estimate the critical energy release rate from creep data, bridging microscopic crack dynamics with macroscopic failure thresholds.

Findings

The model accurately predicts fracture energy within 50% across twenty materials.

Intrinsic surface energy barriers can be deduced from creep dynamics.

Thermal activation and weakening mechanisms influence failure thresholds.

Abstract

In any domain involving some stressed solids, that is, from seismology to general engineering, the strength of matter is a paramount feature to understand. We here discuss the ability of a simple thermally activated sub-critical model, that includes the auto-induced thermal evolution of cracks tips, to predict the catastrophic failure of a vast range of materials. It is in particular shown that the intrinsic surface energy barrier, for breaking the atomic bonds of many solids, can be easily deduced from the slow creeping dynamics of a crack. This intrinsic barrier is however higher than the macroscopic load threshold at which brittle matter brutally fails, possibly as a result of thermal activation and of a thermal weakening mechanism. We propose a novel method to compute the macroscopic critical energy release rate of rupture, G_a, solely from monitoring slow creep, and show that this reproduces the experimental values within 50% accuracy over twenty different materials, and over more than four decades of fracture energy.