Torsional Stresses Near the Bonded Interface of a Tube-to-Tube Connected Cylindrically Orthotropic Circular Shaft with Radial Inhomogeneity

This study uncovers the stress distributions on or adjacent to the bonded interface connecting two sections in a circular shaft subjected to torsional shear loads on the surfaces of both ends. The material in each section is considered to be cylindrically orthotropic with radial inhomogeneity. The derived results in explicit expressions enable us to investigate the trends of variations in stress near the connecting interface due to the varying degree of material anisotropy, forms of end loads, and material inhomogeneity. According to the numerical results of the examples, when both end surfaces are subjected to radially power-distributed torsional shear loads, the interfacial influences on stress distributions will be strongly dependent on the degree of material anisotropy, and the maximum magnitudes of the torsional stresses near the interface can be effectively alleviated by properly introducing a radial inhomogeneity into the material and adjusting the forms of the end torsional loads, even though the end surfaces are sufficiently far from the interface. When one designs the structure of a tube-to-tube connected shaft subjected to torsional loads, besides paying attention to the maximum magnitude of the interfacial longitudinal shear stress, the transverse shear stress adjacent to the interface has to be considered, especially when one section possesses strong anisotropy.