Multilayered ceramic composites - a review

With the aim of improving the toughness of ceramic materials, laminated composites have been successfully developed since Clegg et al. (1990) inserted weak interfaces using very thin graphite layers between silicon carbide sheets and obtained a composite that exhibited non-catastrophic fracture characteristics. The weak interface must allow the crack to deviate either by deflection or delamination; in other words, the interface must exhibit a fracture resistance that is lower than that of the matrix layer. In parallel, ceramic laminated composites with strong interfaces were developed in which the residual tensile and compressive stresses appeared in alternate layers during cooling after sintering. These composites are prepared by stacking ceramic sheets produced by lamination or tape casting or by the sequential formation of layers by slip casting, centrifugation or electrophoretic deposition. The techniques may be combined to obtain a composite with the most adequate configuration. This work presents a review about the obtainment of multilayered ceramic composites as a toughening mechanism of ceramic plates.