Author/Authors :
Goodarzy، M. H. نويسنده School of Metallurgy and Materials Engineering, Iran university of Science & Technology, Tehran, Iran. , , ARABI، H. نويسنده , , Boutorabi، M. A. نويسنده Center of Excellence for High Strength Alloys Technology (CEHSAT), School of Metallurgy and Materials Engineering, Iran University of Science and Technology, Tehran, Iran. , , Seyedein، S. H. نويسنده Center of Excellence for Advanced Materials and Processing (CEAMP), School of Materials and Metallurgical Engineering, Iran University of Science and Technology, Tehran, Iran. , , Shahrokhi، H. نويسنده Department of mechanical Engineering, Azad University Saveh Branch, Iran. ,
Abstract :
Variation in microstructural features of 2024 aluminum alloy plastically deformed by equal channel angular
pressing (ECAP) at room temperature, was investigated by X-Ray diffraction in this work. These include dislocation
density; dislocation characteristic and the cell size of crystalline domains. Dislocations contrast factor was calculated
using elastic constants of the alloy such as C11, C22 and C44. The effect of dislocations contrast factor on the
anisotropic strain broadening of diffraction profiles was considered for measuring the microstructural features on the
base of the modified Williamson-Hall and Warren-Averbach methods. Results showed that the dislocations density of
the solution annealed sample increased from 4.28×1012m-2 to 2.41×1014m-2 after one pass of cold ECAP and the
fraction of edge dislocations in the solution annealed sample increased from 43% to 74% after deformation. This
means that deformation changed the overall dislocations characteristic more to edge dislocations. Also the crystalline
cell size of the solution annealed sample decreased from 0.83?m to about 210nm after one pass of ECAP process at
room temperature.
