表面施加含稀土氧化物薄膜对Fe25Cr高温氧化的“活性元素效应”

EFFECT OF SURFACE\|APPLIED \=RARE EARTH CONTAINING THIN OXIDE FILMS\=ON HIGH\|TEMPERATURE OXIDATION OF Fe25Cr

研究了表面施加含有不同量Ｙ２Ｏ３的Ｃｒ２Ｏ３和Ａｌ２Ｏ３薄膜对Ｃｒ２Ｏ３形成合金Ｆｅ２５Ｃｒ在１０００℃、１０４ＰａＯ２环境中高温氧化的作用．结果发现含Ｙ氧化物薄膜明显降低了Ｃｒ２Ｏ３层的生长速度，而且含Ｙ复合氧化物薄膜的作用大于单一Ｙ２Ｏ３薄膜．此时，Ｃｒ２Ｏ３层表面形貌发生了较大的变化．间接证据表明Ｃｒ２Ｏ３的生长机制由阳离子向外扩散为主转变为阴离子向内扩散为主．通过表面施加含Ｙ的氧化物薄膜产生了全面的“活性元素效应”

The effects of surface\|applied Cr2O3 and Al2O3 thin oxide films containing various concentrations of Y2O3 on the high\|temperature oxidation behaviour of an ordinary Cr2O3 former, Fe25Cr, have been studied at 1000 in 104 Pa oxygen. The thin oxide films with Y2O3 gave rise to a great decrease in the growth rate of the Cr2O3 scale and the effect of multi\|component films was stronger than the single Y2O3 film. The morphology of Cr2O3 scales changed apparently. The indirect evidences showed that the growth mechnism of the Cr2O3 scale converted from predominantly cation diffusing outwards to predominantly anion diffusing inwards. A full reactive element effect(REE) has been developed by the surface\|applied thin oxide films with yttrium. \=