DISLOCATIONS STRUCTURE AND SCATTERING PHENOMENON IN CRYSTALLINE CELL SIZE OF 2024 AL ALLOY DEFORMED BY ONE PASS OF ECAP AT ROOM TEMPERATURE

Variation in microstructural features of 2024 aluminum alloy plastically deformed by equal channel angularpressing (ecap) at room temperature, was investigated by x-ray diffraction in this work. these include dislocationdensity; dislocation characteristic and the cell size of crystalline domains. dislocations contrast factor was calculatedusing elastic constants of the alloy such as c11, c22 and c44. the effect of dislocations contrast factor on theanisotropic strain broadening of diffraction profiles was considered for measuring the microstructural features on thebase of the modified williamson-hall and warren-averbach methods. results showed that the dislocations density ofthe solution annealed sample increased from 4.28×1012m-2 to 2.41×1014m-2 after one pass of cold ecap and thefraction of edge dislocations in the solution annealed sample increased from 43% to 74% after deformation. thismeans that deformation changed the overall dislocations characteristic more to edge dislocations. also the crystallinecell size of the solution annealed sample decreased from 0.83?m to about 210nm after one pass of ecap process atroom temperature.