Investigation of the structure, magnetic and magnetoelastic properties of cobalt ferrite and its derivatives

This study shows that the magnetostrictive properties of cobalt ferrite can be further enhanced by altering the oxygen content during preparation which resulted in the highest strain derivative reported for cobalt ferrite to date. Increase in annealing temperature before quenching the samples to ambient temperature resulted in changes in magnetic and magnetostrictive properties which were not accompanied by observable changes in crystal structure and microstructure. While the saturation magnetization increased, the anisotropy coefficient, coercive field, magnetostriction and strain derivative decreased. The changes show that annealing and quenching heat treatment resulted in cation redistribution between the tetrahedral and octahedral cation sites. Such redistribution can be exploited for property enhancement