The vibration and buckling of sandwich cylindrical shells covered by different coatings subjected to the hydrostatic pressure

The vibration and buckling of sandwich cylindrical shells covered by different types of coatings, such as functionally graded (FG), metal and ceramic coatings and subjected to a uniform hydrostatic pressure using first order shear deformation theory (FOSDT) is discussed. Four types of sandwich cylindrical shells are considered. The volume fraction of FG coatings varies according to a simple power law function of thickness coordinate, while that of the core equals unity. The effective material properties of FG coatings are assumed to be graded in the thickness direction according to an exponential law distribution. The equations of motion of FG sandwich cylindrical shells are deduced using the FOSDT. The closed-form solutions for non-dimensional frequencies and critical hydrostatic pressures are obtained. The influences of compositional profiles of coatings, shear stresses and sandwich shell characteristics on the non-dimensional frequencies and critical hydrostatic pressures for FG and homogeneous sandwich cylindrical shells are discussed.