Modeling of SiCf/SiC composite structures for nuclear components

The use of low activation Ceramic Matrix Composites (CMCs) appears as the m ost promising solution to obtain high safety standards in future fusion pow er reactors. Among them, silicon carbide composites (SiCf/SiC) are the prim ary composite materials being evaluated and developed world-wide for fusion structural applications. Although these composites are already widely used in the aerospace industry, they are relatively new materials for fusion ap plications, and a number of key issues remain still to be solved. Among the m, specific design methodologies for fusion reactor structural components m ust be established. This involves the development and implementation in fin ite-element codes of material models capable to describe the complex non-li near mechanical behavior of those composites. Such a model has been impleme nted in the FEM code CASTEM 2000 used within the CEA. This paper describes the details of the model and identifies the major improvements for the anal yses. Furthermore, if the potential advantages of SiCf/SiC composites over more common metallic materials have to be fully evaluated, appropriate resi stance criteria must be assessed. Specific criteria for CMCs have then been identified and are discussed in the paper. Results obtained with these cri teria are compared with those obtained with more classical ones. The exampl e of application to the Tauro blanket is presented. (C) 2000 Elsevier Scien ce B.V. All rights reserved.