Effect of Sintering Parameters on Microstructure and Properties of Sialon Materials
The influence of some parameters of pressureless sintering on mechanical properties, microstructure and phase composition has been studied. By using different types of silicon nitride as embedding powder it has been shown that, besides weight change, density and bend strength of the samples also depend on the type of powder bed. The composition of the material was varied by changing the ratio of alumina/aluminum nitride while keeping the amount of sintering aid constant. By increasing the oxygen content we found deteriorating mechanical properties and increasing weight loss. The observed variation of microstructure and phase composition with sintering time, temperature and initial composition can be attributed to the changing composition of the liquid phase.
KeywordsOxygen Content Silicon Nitride Pressureless Sinter Bend Strength Increase Weight Loss
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