The kinetics of isothermal and non-isothermal recovery within cold-rolled aluminum alloy

Abstract

Purpose– The purpose of this paper is to study the kinetics of static recovery in cold-rolled aluminum alloy under different heating rates.Design/methodology/approach– Deformation modeling was first performed to assess the distributions of plastic strain and stress within the deformed alloy. In the next stage, thermal analysis and the rate equation of static recovery were employed to determine the progress of static recovery under non-isothermal conditions. Accordingly, a thermal finite element analysis and the Runge-Kutta method were utilized to handle the transient heat conduction and the progress of static recovery. Finally, low temperature annealing heat treatments were conducted to verify the model predictions. Accordingly, the tensile tests were conducted to measure the yield stresses of cold-rolled plates subjected to the subsequent annealing treatment at different temperatures and durations.Findings– The results indicate that the employed algorithm can be used as an appropriate predictive tool for designing a low temperature heat treatment schedule to achieve the desired yield stress.Originality/value– The kinetics of non-isothermal recovery and resulting yield stress are well predicted under practical annealing conditions.