Microstructure Characterization of Nanocrystalline Ni50Ti50 Alloy Prepared Via Mechanical Alloying Method Using the Rietveld Refinement Method Applied to the X-Ray Diffraction

Abstract

Using the Rietveld refinement, we analysed the structural evolution of Ni 50 Ti 50 alloy prepared by mechanical alloying method. The elemental Ti and Ni powders are milled during different milling times (0, 1, 3, 6, 24, and 72 hours) in a high-energy planetary ball mill (Pulverisette 7 premium line). The milled powder specimens were characterized with x-ray Philips X,Pert diffractometer equipped with CuK  radiation source ( Cu 0.15418 nm). We refined the structure of compounds using the MAUD program, and we found structural parameters such as the atomic positions (x, y, z), symmetry, and a space group. Moreover, microstructural parameters such as the lattice parameters (a, b, c), the average crystallite size <L>, microstrains  2  1/2 , the average number of compacted layers, and the phase percentages were also determined. According to the results, at the initial stages of milling (typically of 1-3 h), the structure consists of Ni-based solid solution [f.c.c.-Ni (Ti)],

Comprehensive physicochemical characterization of Algerian coal powders for the engineering of advanced sustainable materials

“…The goodness of fit (GOF) value of 1.26 confirms the accuracy of the Rietveld refinement, ensuring a reliable match between observed and simulated XRD patterns [11]. This high level of accuracy in the analysis affirms the model's capability to accurately represent the coal's phase composition and microstructural details.…”

“…Morphology analysis by Scanning Electron Microscopy (SEM). The comprehensive set of Scanning Electron Microscopy (SEM) images serves as the basis for a detailed morphological and particle size analysis [11] of natural coal samples extracted from Algerian deposits. The SEM micrographs, with their varied magnifications, as illustrated in Fig.…”