Grain Shape Evolution and Prediction for AA6082

The microstructure of aluminum is of high importance for the mechanical properties of the product. During extrusion the material undergoes a wide range of different strain, strain rates and temperature gradients, as described in many research works [1-4]. The final microstructure and texture is the result of the effects of multiple mechanisms as grain shape change, recrystallization, recovery, and grain growth. To get optimized profiles, a well-directed adjustment of the microstructure through process parameter is a typical and critical aim. Therefore, the correlation between extrusion process parameters and the change of texture and grain size needs to be investigated [5]. The present paper describes a study on grain evolution during the first stages of material response to deformation in direct extrusion. The investigation was carried out by means of circular profile extrusion of AA6082 alloy with the aim of evaluating the dependency of texture change on process parameters such as temperature, velocity and extrusion ratio. Sequential experimental measurements on grain size were coupled with strain evaluations of a finite element model in order to define an evolution model, always taking into account existing evolution theories and laws.