Hot Tensile Deformation Behaviour of AA2524-T3 Alloy and Prediction of Johnson–Cook Model Parameters

Abstract

The presented work explores the quasi-static response of AA2524-T3 alloy studied under hot tensile loading. The impact on the flow stress of this alloy due to different strain rates in the range of 0.001 \(\hbox {s}^{-1}\) to 0.1 \(\hbox {s}^{-1}\) and temperatures between 25 and 300 °C are investigated experimentally. The initial microstructural features and subsequent microstructural changes after taking the alloy to various test temperatures, but prior to tensile testing, are characterized through extensive microscopical analysis. The formation of fine cell structures and the occurrence of more intense recovery mechanism are observed at 250 °C. Above this temperature, it is observed the presence of more amount of \(\hbox {S}^{\prime }\) precipitates. After performing hot tensile loading on AA2524-T3 under a various combination of test temperatures and strain rates, the fracture morphology of tested samples are examined. Notably, the ductility of AA2524-T3 alloy decreases marginally with an increase in strain rate up to 200 °C and beyond this temperature, it increases considerably for increase in strain rates. In addition to the experimental study, the parameters of Johnson–Cook constitutive model are determined to predict the flow stress behavior of AA2524-T3 for selected testing conditions. Finally, the strain rate sensitivity and thermal softening coefficient, the key parameters in Johnson–Cook model, are optimized for the chosen test ranges.

Graphic Abstract