The hot flow stress of as-quenched Al - Cu - Mn alloy was modeled using the constitutive equations. The as-quenched Al - Cu - Mn alloy were treated with isothermal hot compression tests in the temperature range of 350–500°C, the strain rate range of 0.001–1 s-1. The hyperbolic sine equation was found to be appropriate for flow stress modeling and prediction. Based on the hyperbolic sine equation, a constitutive equation is a relation between 0.2 pct yield stress and deformation conditions (strain rate and deformation temperature) was established. The corresponding hot deformation activation energy (Q) for as-quenched Al - Cu - Mn alloy was determined to be 251.314 kJ/mol. Parameters of constitutive equation of as-quenched Al - Cu - Mn alloy were calculated at different small strains (≤ 0.01). The calculated flow stresses from the constitutive equation are in good agreement with the experimental results. Therefore, this constitutive equation can be used as an accurate temperature-stress model to solve the problems of quench distortion of Al - Cu - Mn alloy parts.
The simple hyperbolic-sine equation for superplastic deformation and parameters optimization