Polycrystalline Elastic Moduli of Some Hexagonal and Tetragonal Materials

Self consistent values for the shear and bulk moduli of a large number of hexagonal and tetragonal polycrystals are estimated by solving a pair of simultaneous equations for each of both the systems. The equations are solved by a method of iteration using the VRH mean values of the shear and bulk moduli as the zeroth approximation values for the effective moduli. In a majority of cases the Voigt (V) and Reuss (R) limits for both the shear and the bulk moduli are pretty close making the iteration process converge fast. There are, however, a few cases which pose difficulties which can be easily overcome. The theoretical results are compared with the corresponding experimental values wherever available.