TiC/316L不锈钢复合材料的高温氧化行为

High temperature oxidation behavior of TiC/316L stainless steel composites

采用粉末冶金法制备TiC/316L不锈钢复合材料（TiC质量分数为10%），研究该复合材料在700~900℃空气中的恒温氧化行为，分析氧化温度和氧化时间对其氧化行为的影响，并对氧化膜表面的相组成、形貌以及氧化机制进行分析。结果表明：在700~900℃氧化条件下，TiC/316L不锈钢复合材料表面形成的氧化膜以TiO2、Cr2O3、Fe3O4和FeCr2O4为主要组成相，且随氧化时间的延长，TiO2和FeCr2O4的衍射峰逐渐变强，试样在900℃氧化时，氧化膜中的Fe3O4会进一步与O2反应生成Fe2O3。温度从700℃升高至900℃，氧化膜表面铁的氧化物由细条状变为片状，继而发展成短柱状；而Ti的氧化物由大块结状发展成颗粒状，并且颗粒的尺寸随温度的升高而增大。

Powder metallurgic method was used to prepare TiC/316L stainless steel composite （TiC mass fraction is 10%） and the high temperature oxidation behavior of the TiC/316L composite at 700~900 ℃ in air was investigated. The effects of oxidizing temperature and time on the oxidation behavior of the TiC/316L composite were studied, and the reaction products in the oxidation layer as well as the surface morphology of oxidation layer were analyzed. The results show that an oxidation film mainly consisting of TiO2, Cr2O3, Fe3O4 and FeCr2O4 has formed at 700~900 ℃, and the intensities of TiO2 and FeCr2O4 diffraction peaks increase gradually with increasing oxidation time;at 900℃in air, Fe3O4 reacts with O2 to form Fe2O3. From 700 ℃ to 900 ℃, the surface morphology of iron oxide in the oxidation film developes from thin strips, gradually to sheets, and finally forms short columns, while the shape of Ti oxide changed from large knot-shaped to grainy, and the size of particles increases with increasing oxidizing temperature.