About

Composites materials consist basically of two or more phases and are designed in such a way to produce desired properties for engineering application, e.g., in metal ceramic composites it is possible to combine the ability to undergo plastic deformation of the metal with the temperature resistance and hardness of ceramics. Among them there is a big class of advanced composites, functionally graded materials (FGMs), with a continually varying composition in a spatial direction and, accordingly, with continuous varying properties in this direction. The mechanical behavior of composites is evaluated on both microscopic and macroscopic scale levels to take into account inhomogeneities and interactions between inhomogeneities. Metal ceramic composites are applied in different fields, such as, nuclear energy (e.g. nuclear reactor components), aerospace (e.g. rocket engine components, space plane body), engineering (e.g. turbine blade, engine components), energy conversion (e.g. thermoelectric generator, fuel cell) as well as other applications. They are subjected to different thermal and mechanical loadings and have to resist high temperature, wear and aggressive environments which strongly influence the composite behavior and degradation. Cracks can initiate from initial defects or microcracks and appear during manufacturing or service. Therefore, the study of fracture of metal ceramic composites and structures is important for a better understanding of the fracture resistance of composite materials.