Abstract
Functionally graded materials(FGMs) have been developed as ultrahigh temperature resistant materials for aircraft, space vehicles and other engineering applications. Most FGMs are particle-reinforced FGMs and these composition vary on a position. In the study of FGMs, the material properties due to macroscopic combination-law have been adopted. However in order to obtain more correct thermal stresses in the FGMs, it is necessary to analyze thermal stresses by use of the microscopic combination-law. Using the constitutive equations for the particle-reinforced composites, the stress-strain relations of particle-reinforced composites taking into account the effect of the manufacturing process, and the stress distribution in an FGM plate subjected to heating are discussed. The number of damaged particles and the possibility of crack generation taking into account the manufacturing process are also discussed.