Abstract The influence of Al 2 O 3 on the oxidation behavior of SiC f /(SiC + B 4 C) composite materials at 1200 °C in O 2 /H 2 O (40/60) atmosphere was studied employing Scanning Electron Microscope, X-ray Diffraction and Material Universal Testing Machine. Results showed that Al 2 O 3 could impede the crystallization of oxide (cristobalite) during cooling, and lead to a dense and smooth oxidized layer. Furthermore, the strength retention rate increases from 70.44 to 85.94% with Al 2 O 3 after oxidization for 200 h. The above results are attributed to high viscosity and low reaction activity with steam of the aluminosilicates melt. Therefore, Al 2 O 3 can significantly improve the oxidation resistance of SiC f /(SiC + B 4 C) composites in O 2 /H 2 O atmosphere.

中文翻译：

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Al 2 O 3 改性SiC f /(SiC+B 4 C)在1200℃湿氧环境中的氧化行为

摘要 采用扫描电子显微镜，研究了Al 2 O 3 对SiC f /(SiC + B 4 C) 复合材料在O 2 /H 2 O (40/60) 气氛中1200 °C 氧化行为的影响。 -射线衍射和材料万能试验机。结果表明，Al 2 O 3 可以在冷却过程中阻碍氧化物（方石英）的结晶，并形成致密光滑的氧化层。此外，在氧化 200 小时后，Al 2 O 3 的强度保持率从 70.44% 增加到 85.94%。上述结果归因于硅铝酸盐熔体的高粘度和与蒸汽的低反应活性。因此，Al 2 O 3 可以显着提高SiC f /(SiC + B 4 C)复合材料在O 2 /H 2 O气氛中的抗氧化性。