The strength and oxidation of reaction-sintered silicon nitride

  title={The strength and oxidation of reaction-sintered silicon nitride},
  author={Anthony. G. Evans and Roger William Davidge},
  journal={Journal of Materials Science},
The structure of reaction-sintered silicon nitride is studied using scanning electron and optical microscopy at various stages during nitriding, for a range of nitriding and compacting conditions. The strength is then evaluated and interpreted in terms of the microstructure. It is found that fracture always occurs in a brittle manner by the extension of the largest pores. The effects of prolonged annealing in air above 1000† C on both the structure and strength are investigated. At 1400† C… Expand
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