The role of phase transformation (tetragonal – spinel) on the structural and mechanical properties of Ni doped CuFe2O4

Abstract

Abstract Nano-ferrites of Cu 1–x Ni x Fe 2 O 4 (x = 0 to 1 with step 0.2) system was synthesized utilizing the flash auto combustion process annealed at 600 o C for 3 h. The structural characterization for synthesized samples was carried out using x-ray Diffraction (XRD), Fourier transition infrared spectroscopy (FTIR) and transmission electron microscopy (TEM). The hardness of the prepared material was measured using micro-indentation creep technology. XRD pattern verified the creation of a single-phase cubic spinel structure. The undesired CuO phase forms around $$\:2\theta\:={50}^{^\circ\:}\:$$ for pure Copper ferrite and decreases with increasing Ni content. The average crystalline size decreases from 27.92 nm to 13.28 nm by doping process from x = 0.2 to x = 1 which retards the growth of crystalline size. FTIR spectra are distinguished by the presence of two prominent absorption bands, ν 2 for the octahedral site and ν 1 for the tetrahedral site, in the range of approximately 593 and 471 cm − 1 , respectively. FTIR analysis verified the formation of the ferrite system’s spinel structure. The TEM images show a nanocrystalline nature with some agglomeration and the crystallites are spherical in shape which their sizes are agrees well with that obtained from XRD measurements. The hardness decreases as the dwell time increases. The hardness and yield strength (Y) values were significantly improved due to the decrease in the crystallite size after Ni doping. The stress exponent (n) value increases by increasing Ni content which means that the mechanical properties improved due to increment of resistance.