原位TiN/O′-Sialon材料的低温氧化行为研究

Study on low-temperature oxidation of in-situ TiN/O′-Sialon composite

采用热分析法研究了原位TiN/O′ Sialon材料在低温下 (80 0～ 10 0 0℃ )的氧化行为 结果表明 ,在 80 0～10 0 0℃的空气中 ,TiN氧化为TiO2 ,O′ Sialon不发生氧化 ,时间足够长 ,材料转变为原位TiN/O′ Sialon复相材料 材料表面无“保护膜”生成 氧化过程遵循对数规律 :Δm/A=Klgt+C,反应表观活化能 5 6 1kJ·mol-1

The low temperature oxidation behavior of in situ TiN/O′ Sialon in the temperature range 800～1 000 ℃ was studied by thermoanalysis method.The results indicate that only the oxidation of TiN to TiO 2 takes place whereas O′ Sialon is not oxidized in atmosphere at 800～1000 ℃;if the exposure time is long enough,TiN/O′ Sialon will be oxidized to in situ TiN/O′ Sialon.There is no protective scale formed in the surface of the sample.The oxidation behavior follows the logarithmic law.The apparent activation energy for oxidation is 56.1 kJ·mol -1 .The increase in oxygen partial pressure of environment results in an obvious increase in oxidation weight gain.