Elastic Properties of Cr-doped Mn Ferrite

Background The mechanical properties of Mn-Cr ferrite of different compositions are important for industrial applications in everyday life. Ferrites are used in electric choke coils, electric transformers, and many other electronic and optical devices. The elastic properties can be understood by studying the longitudinal sound velocity ( V l ) and shear velocity ( V s ). Results The longitudinal sound velocity ( V l ) and shear velocity ( V s ) are measured at room temperature by pulse transmission technique at the frequency of 1659 Hz, which is ideally representing the mechanical properties of the ferrite crystal. The shear sound velocity was found to be around 4 × 10 3 m∕s while the longitudinal sound velocity was ranging according to the doping concentration from 6 × 10 3 to 1 × 10 4 m∕s. The behavior of Young’s modulus ( E ), rigidity modulus ( n ), mean sound velocity ( V m ), and Debye temperature ( θ D ) is quite similar, where a change in the slope was noticed at Cr concentration higher than 0.7 in the spinel lattice. Conclusion We have characterized the elastic properties of the spinel structure Mn-Cr ferrite with different Cr ion concentration at a fixed sound frequency using the pulse transmission technique. The longitudinal sound velocity showed an increase with increasing Cr ion concentration, the rigidity constant as well as Debye temperature, Isotropic compressibility, and the acoustic impedance showed behavioral change at Cr ion concentration x = 0.7 which is correlated to the intra-ionic distances change due to the replacement of Fe ions with smaller size Cr ions.