Steady thermal stresses in a functionally gradient material plate

A functionally gradient material which decreases thermal stresses has been developed for structural components and/or mechanical elements in fields such as nuclear, aircraft and space engineering. Steady-state thermal stresses in a plate made of the functionally gradient material are discussed. The main theme of this subject is to determine the available temperature region where the minimum factor of safety is one or more, and how to distribute the components of the material in the funcitonally gradient material to decrease thermal stresses, for different mechanical boundary conditions. We discuss a two-layer laminated plate and functionally gradient material plate whose components are ZrO2 and Ti-6Al-4V. The optimal functionally gradient material plate, which makes the minimum stress ratio largest, is determined for each mechanical boundary condition. (author)