Thermographic Study of AZ31B Magnesium Alloy under Cyclic Loading: Temperature Evolution Analysis and Fatigue Limit Estimation

Abstract

In this paper, infrared thermography was employed to study the fatigue process of AZ31B magnesium alloy. In order to eliminate the interference caused by the temperature rise of the fixture, a data processing method was proposed, which is based on a special model to describe the temperature change of the specimen. Based on the temperature data after processing, the temperature evolution indicates that AZ31B magnesium alloy has undergone cyclic hardening during fatigue. Three different temperature indicators were selected to evaluate the fatigue limit based on the evolution curve after processing. In addition, the experimental results showed that the temperature data processed by the proposed method can be used to estimate the fatigue limit of AZ31B magnesium alloy. Experiments were performed for both extrusion and transverse directions in consideration of the anisotropy of the AZ31B.

Fatigue Performance Evaluation of AZ31B Magnesium Alloy Based on Statistical Analysis of Self-Heating

“…A large number of thermal images will be generated during the entire fatigue test process. For more experimental details, see reference [ 26 ].…”

“…Changes in thermal boundary conditions can interfere with the measurement of self-heating [ 28 ]. Therefore, maintaining consistent thermal boundary conditions is a crucial experimental requirement for fatigue research based on self-heating [ 26 ].…”

“…In this work, a data processing approach [ 26 ] was adopted to control the thermal boundary conditions. This is different from the experimental method of adding an external temperature control device in some studies [ 30 ].…”

“…Using the data processing method mentioned above ensures that the temperature on the boundary is always kept at zero [ 26 ]. It means that the boundary conditions of the thermal model are fully controlled.…”

“…The purpose of this paper is to study the fatigue performance of AZ31B magnesium alloy by analyzing the self-heating in both the extrusion direction and the transverse direction. In particular, a data processing method [ 26 ] was adopted to ensure that the self-heating of the material can be reflected in a reasonable way. The change of self-heating with time under constant load was investigated by detecting the evolution of temperature rise during high cycle fatigue.…”