The International Conference “Condensed Matter Research at the IBR-2” has been held from October 12 to 16, 2020. Micro-Stress has presented the paper “Study of Residual Stresses in Extruded Aluminium Alloys After Thermal Treatments”. The poster has been selected to publish an extended version in the Journal of Surface Investigation.
Abstract: The aim of this study is to calculate the macroscopic and microscopic residual stresses (M-RS and m-RS) in extruded cylindrical samples of non-ageing aluminium alloy 5083 (Al-Mg) generated with a treatment at 530°C followed by quenching in water. It was also planned to study the RS state when slow (furnace) cooling is carried out. We start from the premise that the alloy is single-phased and not isotropic at the microscopic scale; it consists of a multitude of grains that present different mechanical response depending on their crystallographic orientation and their neighboring grains.The plastic anisotropy of the individual grains gives rise to non-homogeneous plastic deformation in the axial direction during the extrusion process, which results in the development of a crystallographic texture (fiber texture). Due to the inhomogeneity of the extrusion
process (friction with the die), a texture gradient is generated across the diameter of the bar. The m-RS depends on the treatment imposed, the microstructure, and the mechanical behavior of the alloy grains. The microstructural parameters of each grain were obtained employing the electron back-scattered diffraction, EBSD. Genetic programming, GP, was used to calculate m-RS considering that each diffraction peak describes the stress distribution of a group of grains having a certain orientation, size and environment. The GP algorithms assigns to each grain a stress value according to the peak distribution and the microstructural parameters of these grains.
