X-ray Diffraction Analysis of a Class of AlMgCu Alloy Using Williamson–Hall and Scherrer Methods

Abstract

AlMgCu alloy samples with 70 wt.% Al and varying Cu and Mg compositions have been fabricated. The fabricated samples were characterized by x-ray diffraction measurement and the diffraction patterns obtained. The samples were also subjected to hardness and tensile tests to determine the mechanical properties. A study of the diffraction patterns was done to determine average crystallite size and internal strains using Scherrer’s formula and Williamson–Hall analysis, assuming uniform deformation model. The results of the study show a significant variation in the average crystallite sizes obtained by the two methods, even though the trend for all the samples remained identical. This variation is attributed to the presence of strain in the crystal system. Also, it was observed that higher values of internal strain correspond to the higher values of ductility and lower values of Young’s modulus, ultimate tensile strength, yield stress and hardness. This implies that smaller crystallite sizes correspond to lower hardness values and higher ductility.