Fracture Characteristics of Layered and Nano-Particle Reinforced Si3N4

摘要: In recent 10–15 years several attempts have been made with the aim of improving mechanical properties, mainly flaw tolerance and reliability, silicon nitride based structural ceramics. As a result, fracture properties were significantly improved. This happened due to close cooperation scientists in basic applied research detailed study microstructure characteristics ceramics influence processing steps on these materials as well. The main scientific approaches used for this purpose are following ones, Fig. 1: The diminution approach — strength (characteristic Weibull modulus) by reducing critical defect’s size, [1–5], The activating localized bridges behind crack tip form mechanisms frictional interlocking or pull out, [6–10], Nano-particle dispersion strengthening values incorporating nano-sized second phase particles into matrix, [11–15], The laminar structure reliability designing (layered) composites promoted deflection at interlayer boundaries utilizing compressive residual stresses arisen different thermal expansions neighbouring layers, [16–20].