Pop-in crack propagation monitoring for AA2024-T3 ductile alloy

This paper demonstrates the use of temperature change, induced by thermo-mechanical effect, as a means of monitoring the pop-in crack propagation of ductile materials. Center crack tensile (CCT) tests are performed at room temperature using 1/4" thick AA2024-T3 aluminum alloy specimens at different loading speeds. The temperature variation in the vicinity of the crack tip is measured and correlated with the changes in the applied load and fractographs. The results show that the load and temperature curves comprise three distinct regions, corresponding to the initial thermo-elastic stage, a stable cracking extension stage, and an unstable cracking extension stage, respectively. The load and temperature characteristics in each stage are highly distinctive and therefore provide a reliable means of monitoring the state of the crack propagation process.