Analytical modeling of stress–strain behavior at 1873 K of alumina/YAG composite compressed parallel and perpendicular to the solidification direction

The strain rate-dependence of the stress–strain curve and flow stress at 1873 K of the directionally solidified eutectic alumina/YAG composite under applied compressivse stress parallel (0°) and perpendicular (90°) to the solidification direction were analyzed by a finite element model and by the isostrain and isostress models based the rule of mixtures. The experimentally measured stress–strain curve and flow stress in the steady state plastic deformation region of the composite was described by a finite element model for both 0° and 90° compression directions. The influence of the microstructural deviation of alumina and YAG from the theoretical isostrain and isostress models on the overall flow stress was discussed for both 0° and 90° compression directions, based on the calculated spatial distribution of the equivalent strain rate.