Two compositions of ZrB2-based ceramic composites containing Si3N4, Al2O3 and Y2O3 have been hot-pressed at different temperatures between 1673 and 1773?K for 60?min in vacuum. The densification behavior of the composites was examined during the sintering process. The microstructures of the composites were characterized by scanning electron microscopy, and the crystalline phases were identified by x-ray diffraction. The effects of Al2O3 and Y2O3 additives on the densification behavior and flexural strength were assessed. A relative density of ~95% was obtained after sintering at 1723?K or higher temperatures. The microstructures of the composites consisted of (Zr,Y)B2, α-Si3N4 and Y3(Al,Si)5O12 phases. The room-temperature flexural strength increased with the amount of additives and approached 1?GPa.
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机译：含Si 3 N 4 ，Al 2 O 3的ZrB 2 基陶瓷复合材料的两种成分和Y 2 O 3 已在1673和1773？K之间的不同温度真空中热压60分钟。在烧结过程中检查了复合材料的致密化行为。通过扫描电子显微镜表征复合材料的微观结构，并通过X射线衍射鉴定结晶相。评估了Al 2 O 3 和Y 2 O 3 添加剂对致密行为和抗弯强度的影响。在1723？K或更高的温度下烧结后，相对密度约为95％。复合材料的微观结构包括（Zr，Y）B 2 ，α-Si 3 N 4 和Y 3 （Al，Si） 5 O 12 相。室温挠曲强度随添加剂的添加而增加，并达到1？GPa。
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