The empirical model of dynamic recrystallization (DRX) coupled with DEFORM 3D® software (based on the finite element method (FEM)) was used to predict the microstructural evolution of the AA7075 processed by four passes of equal channel angular pressing (ECAP) at 250° C. The DRX model parameters were taken from the literature. The simulation results showed that the DRX exhibited a heterogeneous distribution from the back to the frontal part of the sample and this heterogeneity markedly diminished in the fourth pass. The recrystallized volume fraction reached 50% in most of the sample in the fourth pass and the average grain size did not show significant changes, going from an initial value of 16.4 μm to 12.5 μm. This latter result was attributed to the fact that DRX occurred partially even for the last pass. Experimental testing of ECAP was conducted by using the same conditions of computational simulation. The validation of model was performed by comparison of average grain size values with those obtained experimentally by means of image analysis applied on micrographs that were acquired by means of optical microscopy (OM). Hardness and peak load values also indicated the occurrence of a partial dynamic recrystallization and recovery.

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