Effects of beryllium additions on the oxidation of nickel aluminide and titanium aluminide based intermetallics

摘要

The effects of Be additions on the oxidation behavior of (beta)-NiAl in moist air at 1,000 C and borderline alumina-forming (gamma) (TiAl) + Laves Ti- Al-Cr based alloys at 800 C and 1,000 C in dry and moist air were investigated. The addition of Be to (beta)-NiAl suppressed the formation of transient alumina, and resulted in the formation of a protective BeAl(sub 2)O(sub 4) spinel phase. In dry air, the addition of Be to the Ti-Al-Cr alloys also resulted in the formation of a protective BeAl(sub 2)O(sub 4) spinel phase. In moist air, only Ti-Al-Cr-Be alloys with a high Cr content (10 to 15 a/o) formed the protective BeAl(sub 2)O(sub 4) scale.