Microstructure and Strength of Silicon nitride with Film on the Surface

Abstract

The experimental results obtained in this study demonstrated the feasibility of improving the bending strength of rough-ground Si3N4 coated with polymer ceramic precursors and subsequently pyrolyzing the polymer coating. Double coating with 10 mass% polycyclomthylsilazane solution provided the smooth surface, while microcracks were still existence. Increase in the strength of 150MPa was achievable via polymer coating and pyrolyzing while the improvement in the strength variation in terms of the Weibull modulus was insignificant.