稀土铁铬铝合金的高温氧化TEM研究  

TEM Studies of Oxidized Iron-Chrominum-Aluminium-Rare Earth Alloy Cross Sections

作　　者：杜国维[1] 袁之良[1] 肖治纲[1] 

机构地区：[1]北京科技大学材料物理系

出　　处：《北京科技大学学报》1993年第4期408-413,共6页Journal of University of Science and Technology Beijing

摘　　要：通过透射电镜对Fe-25％Cr-6％Al-RE(富镧)合金氧化行为进行研究.结果表明:经1200℃恒温2h纯氧中氧化,合金中镧以六方La_2O_3微小颗粒沉淀在氧化膜中α—Al_2O_3晶粒的顶端及晶界上。它们阻碍铝向表面扩散,抑制氧化膜的侧向生长;在1200℃/室温之间热循环氧化历程.稀土组元加快了合金的内氧化。它们以氧化铝、氧化镧形式出现,在靠近氧化膜/金属界面,立方La_2O_3颗粒平行于晶界并在合金基体上沉积。The oxidation behavior of Fe-25%Cr-6%Al-RE(rich Lanthanum) alloy in pure oxygen at 1 200℃ has been examined by transmission electron microscopy. It was shown: after oxidation at 1 200℃ for 2 h Lanthanum in alloy precipitated as hexagonal structure La2O3 particles at the top of α-Al2O3 grains or the grain boundaries in the oxide scale. The aluminium atoms outward diffusion and the lateral growth of the oxide scale are prenvented; during 1 200℃ / room temperature thermal cyclic oxidation, rare, earth elements could speed up internal oxidation rate as alumina and lanthanum oxide appeared. A cubic La2O3 particles parallel to the grain boundaries in the alloy.

关 键 词：高温氧化 氧化镧 铁铬铝合金 TEM 

分 类 号：TG146.21[一般工业技术—材料科学与工程]