Mechanical behaviour and failure phenomenon of an in situ toughened silicon nitride
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The Weibull modulus, fracture toughness and crack-growth resistance of an in situ toughened, silicon nitride material used to manufacture a turbine combustor were determined from room temperature to 1371 °C. The material exhibited an elongated grain structure that resulted in improved fracture toughness, non-linear crack-growth resistance, and good elevated-temperature strength. However, low-temperature strength was limited by grains of excessive length (30–100 μm). These excessively long grains were surrounded by regions rich in sintering additives.
KeywordsPolymer Silicon Nitride Fracture Toughness Mechanical Behaviour
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