Fatigue Damage Evaluation of Aviation Aluminum Alloy Based on Strain Monitoring

Abstract

A metal fatigue damage model is established in this study by employing real-time strain monitoring to evaluate the damage state of metal materials. The fatigue life simulation, based on crystal plasticity finite element analysis, establishes the constitutive relationship between strain and damage before microcrack initiation in the low-cycle fatigue state of aerospace aluminum alloy. Subsequently, a comprehensive analysis of the strain–damage relationship is conducted under various stress conditions. Electron backscattering diffraction analysis (EBSD) is used to examine the fatigue damage state of the grooved specimen before initiating fatigue cracks at various stages. This analysis validates the metal fatigue damage model proposed in this paper and is based on strain monitoring, contributing to the enhanced confirmation of the model’s accuracy.

Keywords

• strain monitoring
• crystal plastic finite element
• fatigue crack initiation life
• EBSD