Abstract ZrB2 composites reinforced with SiC of two different particle sizes (coarse ~30 μm and fine ~5 μm) were processed using spark plasma sintering. The oxidation behaviour of the synthesised composites was investigated at 1500 °C under two different partial pressures of oxygen. At higher oxygen partial pressure of 0.21 atm, coarse SiC reinforced ZrB2 composite developed thicker oxide layers as compared to that of fine SiC reinforced ZrB2 composite. The thicker silica layer provides an enhanced oxidation resistance for extended exposure periods of greater than 3 h. However, at lower oxygen partial pressure of 2 × 10−5 atm, fine SiC reinforced ZrB2 composite showed better oxidation resistance due to segregation of finer ZrO2 particles on the surface, which prevented inward transportation of oxygen.

中文翻译：

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粗、细 SiC 增强 ZrB2 在再入大气压力下的氧化行为

摘要 使用放电等离子烧结处理用两种不同粒径（粗~30 μm 和细~5 μm）的 SiC 增强的 ZrB2 复合材料。在 1500 °C 和两种不同的氧分压下研究了合成复合材料的氧化行为。在 0.21 个大气压的较高氧分压下，与细 SiC 增强 ZrB2 复合材料相比，粗 SiC 增强 ZrB2 复合材料形成更厚的氧化层。较厚的二氧化硅层可在超过 3 小时的延长暴露时间内提供增强的抗氧化性。然而，在 2 × 10-5 atm 的较低氧分压下，细小的 SiC 增强 ZrB2 复合材料由于更细的 ZrO2 颗粒在表面偏析而表现出更好的抗氧化性，这阻止了氧气的向内传输。