Elastic behaviour of Ni-Cd ferrites

The ultrasonic compressional velocity (V-l) and shear velocity (V-s) in nic kel-cadmium ferrites having the composition formula Ni1-xCdxFe2O4 where x = 0.2, 0.4, 0.5, 0.6 and 0.8 are measured using the ultrasonic pulse transmi ssion technique. The elastic moduli of the specimens are computed and corre cted to zero porosity. The observed variation of elastic moduli with compos ition has been interpreted in terms of the binding forces between the atoms of the spinel lattice. A linear relationship between the Debye temperature (theta(D)) and the average sound velocity (V-m) has been observed. It is i nteresting to note that the rigidity modulus shows a linear variation with the Young's modulus of these specimens as observed in the case of nickel-zi nc ferrites. (C) 1999 Elsevier Science B.V. All rights reserved.