反应溅射Al_2O_3膜对TiAl抗高温氧化性能的影响

EFFECT OF REACTIVELY-SPUTTERED Al_2O_3 FILMS ON OXIDATION RESISTANCE OF TiAl

研究了反应溅射Al2O3膜对TiAl抗高温氧化性能的影响结果表明，在800和900℃，Al2O3膜大大提高TiAl的抗氧化性能在800℃氧化100h后，Al2O3膜及TiAl基体几乎未发生变化；在900℃氧化时，TiAl中Al优先氧化形成Al2O3，使Al2O3膜增厚，龟裂纹被弥合，仅有少量TiO2出现在大的裂纹处1000℃氧化时，原始Al2O3膜变得不连续。

Effect of reactively-sputtered Al2O3 film on oxidation resistance of TiAl intermetallics was studied at 800~ 1000℃ in static air. The results showed that Al2O3 film improved the oxidation resistance of TiAl remarkably at 800 and 900℃. At 800℃, the Al2O3 film and TiAl substrate didn't show any change after 100h oxidation, which indicated that the Al2O3 film acted as a very effective barrier between the oxidizable atmosphere and TiAl alloy. At 900℃ the preferential formation of Al2O3 under the low oxygen pressure resulted in the thickening of the Al2O3 film and the blocking of cracks, also a littler rutile formed along cracks. At 1000℃, the Al2O3 film was unable to resist the oxidation of TiAl. After 40h oxidation, the Al2O3film became uncontinuous and nonprotective.