Texture development in Al alloys during tensile testing

Abstract

Abstract Tensile tests were made on commercially pure Al (A1050), Al-4.4 wt.% Mg (A5182) and Al-4 wt.% Cu (A2017) alloys by varying the test temperature and the strain rate. Textures developed at various stages of the tensile deformation were investigated with the orientation distribution function analysis. During the tensile test of pure Al with a strain rate of 3 × 10–4 s –1 at 20 °C, the tensile axis readily rotated toward the <111> stable end orientation. However, such a rotation occurred only at the later stage of the tensile deformation near the tensile stress, where the stress– strain curve became flat, and where work hardening was almost saturated. It is suggested that the size and the morphology of the dislocation cell, which had developed up to this stage, played a significant role in the subsequent texture development. In fact, the addition of Mg and Cu, which inhibited the development of the well-defined cell structure due to the Portevin –Le Chatelier effect, strongly suppressed the rotation of the tensile axis toward <111>. In all the materials investigated, textures were not affected by the strain rate and also by the temperature of the tensile test.