Paper Title
Mathematical Modeling Of The Stress–Strain Curves Of Az91 Magnesium Alloy During Hot Compression

Abstract
In this investigation, hot compression tests were performed at 230 °C-290 °C and strain rate of 0.001-0.1 s -1 to study hot deformation behavior and flow stress model of AZ91 magnesium alloy. In order to eliminate the effect of inhomogeneous deformation in compression tests, the numerical correction factors were employed. The effects of the temperature and strain rate on hot deformation behavior have been expressed in terms of an exponent-type Zener–Hollomon equation. A A-section exponential mathematical model was also utilized for prediction of flow stress of this magnesium alloys in compression. The validity of the model was demonstrated by comparing the experimental data with the numerical results. The predicted stress–strain curves are in a very good agreement with those obtained experimentally, both illustrating the occurrence of dynamic recrystallization. Also, in both cases, the peak and steady-state stresses raised with decreasing temperature and increasing strain rate. Keywords- Flow Stress; Mathematical Model ; Hot Compression; Dynamic Recrystallization; AZ91