Material degradation due to moisture and temperature. Part 1: Mathematical model, analysis, and analytical solutions

TL;DR

This paper develops a thermodynamically consistent mathematical model to analyze material degradation caused by moisture and temperature under large strains, providing semi-analytical solutions for hyperelastic solids.

Contribution

It introduces a novel large-strain degradation model with analytical solutions, advancing understanding of material behavior under adverse environmental conditions.

Findings

Model captures large-deformation degradation effects

Provides semi-analytical solutions for canonical problems

Enhances understanding of hyperelastic material response

Abstract

The mechanical response, serviceability, and load bearing capacity of materials and structural components can be adversely affected due to external stimuli, which include exposure to a corrosive chemical species, high temperatures, temperature fluctuations (i.e., freezing-thawing), cyclic mechanical loading, just to name a few. It is, therefore, of paramount importance in several branches of engineering -- ranging from aerospace engineering, civil engineering to biomedical engineering -- to have a fundamental understanding of degradation of materials, as the materials in these applications are often subjected to adverse environments. As a result of recent advancements in material science, new materials like fiber-reinforced polymers and multi-functional materials that exhibit high ductility have been developed and widely used; for example, as infrastructural materials or in medical devices (e.g., stents). The traditional small-strain approaches of modeling these materials will not be adequate. In this paper, we study degradation of materials due to an exposure to chemical species and temperature under large-strain and large-deformations. In the first part of our research work, we present a consistent mathematical model with firm thermodynamic underpinning. We then obtain semi-analytical solutions of several canonical problems to illustrate the nature of the quasi-static and unsteady behaviors of degrading hyperelastic solids.