Structural, Mechanical, Electrical and Magnetic Properties of Mn–Zn Substituted Ca-hexaferrites

Abstract

In the present investigation, the samples with chemical composition Ca(CoTi)_0.5(MnZn)_x/2Fe_11–xO₁₉ with (x = 0 to 1.0) have been synthesized using perfect stoichiometric proportions of reacting oxides by standard ceramic technique. The pellets of 15 mm diameter were prepared and sintered at 1313 K in air atmosphere for 106 h and characterized by using XRD and SEM. XRD studies of the samples showed hexagonal magnetoplumbite (M) structure with unit cell dimensions “a’ and “c” varies from 5 to 6 Å and 21 to 23 Å pertaining to space group P6₃/mmc (No. 194). The mass density of the ferrites were found to vary linearly and depend upon the sample’s mass and volume. The X-ray density depends on lattice constant and molecular weight of the sample. The computation of porosity has been done by considering bulk and X-ray density of the studied samples. The variation in the values of lattice parameter has to be recorded with increase in Mn–Zn concentration. The elastic properties of Mn–Zn doped Ca-hexaferrite have been studied using ultrasonic pulse transmission technique at 100 kHz at 300 K. The field-dependent electric and magnetic properties of prepared Ca-hexaferrite powder were investigated at different temperatures.

Keywords: XRD, X-ray density, porosity, SEM, Poisson’s ratio, Curie temperature.