The magnetic behaviour of two ferromagnetic oxides and two ferrimagnetic oxides (ferrites) are compared to study the effect of magnetocrystalline anisotropy on thermal-history-dependence of magnetization of these ordered magnetic systems. All four compounds show thermomagnetic irreversibility (M_FC >M_ZFC) below a certain temperature,T_irr. The highly anisotropic ferromagnetic oxide, SrRuO₃ and the hard ferrite, SrFe₁₂O₁₉ show sharp peaks belowT_c in theirM_ZFC(T) curves, whereas for the soft ferrite Ni_0.8Zn_0.2Fe₂O₄ and the low anisotropic ferromagnetic oxide La_0.7Ca_0.3MnO₃ only a broad maximum is observed inM_ZFC, when measured in small magnetic fields. The shapes of theM_ZFC(T) curves are inversely-related to the magnitude of the coercivities (H_c) of the compounds in relation to the applied field, and the temperature dependence of H_c.M_FC andM_ZFC are related through the coercivity for all four magnetic systems.

The solid solutions of Sn_1–𝑥Ti_𝑥O₂ (0.0 < 𝑥 < 0.25) were prepared by the usual high temperature ceramic processing techniques with small amounts of dopants such as Nb, Co, Al. The electrical measurements (log 𝐼–log 𝑉) on the ohmically metal electroded sintered pellets showed the non-linear behaviour. The nonlinear coefficient was found to decrease from 12 to 3 with increase in 𝑥. On the other hand, the breakdown voltage (𝐸_b) showed the increase with the increase in 𝑥. This complex electrical behaviour is explained on the effects of the three dopants (as varistor former, performance enhancer and highlighter) on the microstructural features of the dense pellet.

A new combustion route for the synthesis of 𝛾-Fe₂O₃ is reported by employing purified 𝛼-Fe₂O₃ as aprecursor in the present investigation. This synthesis which is similar to a self propagation combustion reaction, involves fewer steps, a shorter overall processing time, is a low energy reaction without the need of any explosives, and also the reaction is completed in a single step yielding magnetic iron oxide i.e. 𝛾-Fe₂O₃. The as synthesized 𝛾-Fe₂O₃ is characterized employing thermal, XRD, SEM, magnetic hysteresis, and density measurements. The effect of ball-milling on magnetic properties is also presented.

Rubber ferrite composites containing various mixed ferrites were prepared for different compositions and various loadings. The magnetic and dielectric properties of the fillers as well as the ferrite filled matrixes were evaluated separately. The results are correlated. Simple equations are proposed to predetermine the magnetic and dielectric properties. The validity of these equations is verified and they are found to be in good agreement. These equations are useful in tailoring the magnetic and dielectric properties of these composites with predetermined properties.

A simple coprecipitation technique is described for the preparation of tin substituted zirconium titanate ceramic powders.

When tin oxide is doped with Sb₂O₃ and CoO, it shows highly nonlinear current (𝐼)–voltage (𝑉) characteristics. Addition of CoO leads to creation of oxygen vacancies and helps in sintering of SnO₂. Antimony oxide acts as a donor and increases the conductivity. The results are nearly the same when antimony oxide is replaced by tantalum oxide. The observed nonlinear coefficient, 𝛼 = 30 and the breakdown voltage is 120 V/mm.