The flow behavior of homogenizated Al-Mg-Si-La aluminum alloy during hot deformation

The high temperature flow behavior of Al-Mg-Si-La alloy has been studied by isothermal compression test in the temperature range bwtween 350 degrees C and 500 degrees C and at strain rates from 0.01 s(-1) to 1 s(-1). Based on the experimental data of thermal simulation, the true stress-true strain curve of the alloy is obtained. The constitutive model containing strain is established using Arrhenius equation and Z parameter to predict the effect of strain rate and temperature on hot deformation behavior. The good agreement between the experimental and predicted results of true strain-true stress indicated that this model can estimate the flow stress accurately. The relationship between the material constants (Q, lnA, n and alpha) and the true strain can be expressed by the 6th order polynomial function. In addition, it is found that the average thermal deformation activation energy in this study is lower than reported values.