A national project for the development of functionally gradient materials (FGMs), which is directed toward exploiting basic technologies required for the development of super-heat-resistant materials capable of space plane applications, is in progress. The FGM is a new composite material whose composition and microstructure vary continuously from place to place in ways designed to provide it with the maximum function of mitigating the induced thermal stress. The research activities of the program are divided among three groups: the Material Design Group, Material Synthesis Group, and Material Evaluation Group. This paper presents an overview of the current status of the FGM program with special focus on the research activities in the Material Evaluation Group. In order to provide material design data and evaluate the mechanical and thermal barrier functions of FGMs supplied from the Material Synthesis Group, the following testing methods are being developed: (1) small punch test, (2) laser heating thermal shock test, (3) thermal shielding performance test. Brief descriptions for these testing procedures and the experimental results obtained to date are given. Finally, the significance of the standardization of the testing procedures and the establishment of a material property data base are discussed for the interdisciplinary interaction among the three research groups.
|Number of pages
|JSME International Journal, Series 1: Solid Mechanics, Strength of Materials
|Published - 1990