On the design of rotating elastic shrink fits with annular inclusion and functionally graded hub

Shrink fits are found frequently in mechanical engineering as an efficient means of connecting a cylindrical inclusion with an annular hub. For reliable operation, the interface pressure between the components should be as large as possible. Although in some cases this may be achieved by a partially plastic design, there are many applications where the device should behave elastically. In the present study, the use of a functionally graded material for the hub is proposed, and particularly an annular inclusion is considered. It is shown that – depending on the radii ratios and the degree of grading – qualitatively different types of mechanical behavior are possible, and that in general by appropriate grading a much better performance at rotation can be achieved, accompanied by a substantial saving of weight. These issues are discussed in detail, and the analytically obtained results provide a comprehensive means for the practicing engineer to decide whether this type of shrink fit might be advantageous for some applications.