The Effects of Beryllium Additions on the Oxidation of Nickel Aluminide and Titanium Aluminide Based Intermetallics
نویسندگان
چکیده
The effects of Be additions on the oxidation behavior of ~-NiAl in moist air at 1000°C and borderline alumina-forming y (TiAI) + Laves Ti-Al-Cr based alloys at 800°C and 1000°C in dry and moist air were investigated. The addition of Be to ~-NiAl suppressed the formation of transient alumina, and resulted in the formation of a protective BeAl20 4 spinel phase. In dry air, the addition of Be to the Ti-AI-Cr alloys also resulted in the formation of a protective BeAl20 4 spinel phase. In moist air, only Ti-Al Cr-Be alloys with a high Cr content (10 to 15 alo) formed the protective BeAl20 4 scale.
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