Abstract
The process of extrusion is responsible for a strong anisotropy of mechanical properties in many aluminium alloys, specifically with respect to the position of the material in the extruded profile. The inhomogeneity and anisotropy of mechanical properties through the profiles of AlMg3 and AlCuMgLi alloys have been investigated by the measurements of the acoustic emission (AE). Extruded profiles were exposed to a solution heat treatment and, for the AlCuMgLi alloy, also to a subsequent artificial aging. AlMg3 alloy is a solid solution and, therefore, non-age hardenable alloy. Samples taken from different positions along the extrusion direction (ED) and in the transversal direction (TD), i.e. perpendicular to ED were deformed in tension at room temperature (RT) and at an initial strain rate of 4 × 10^-4 s^-1. The results of AE are related to deformation curves and discussed with respect to microstructural changes during plastic deformation.

Key words
AlMg3 (AA5754) alloy, AlCuMgLi (1441) alloy, acoustic emission, direct extrusion, artificial aging

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