BBAuthors: Abdellatif, M.H.; Advisor: -; Participants: Azab, A.A. (2019)
The longitudinal sound velocity (Vl) and shear velocity (Vs) 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 × 103 m∕s while the longitudinal sound velocity was ranging according to the doping concentration from 6 × 103 to 1 × 104 m∕s. The behavior of Young’s modulus (E), rigidity modulus (n), mean sound velocity (Vm), and Debye temperature (θD) is quite similar, where a change in the slope was noticed at Cr concentration higher than 0.7 in the spinel lattice. 
