CHARACTERISTICS OF A MULTICOMPONENT NB-TI-AL ALLOY VIA INDUSTRIAL-SCALE PRACTICE

Within the spectrum of advanced intermetallic materials, an alloy cont aining 44Nb-35Ti-6A1-5Cr-8V-1W-O.5Mo-0.3Hf (at.%) was investigated in the industrial-scale produced condition. The alloy was tensile tested in air from room temperature to 1000 degrees C and in vacuum at 750 an d 850 degrees C. Results of this study have shown that the alloy can b e commercially produced and has adequate ductility for its secondary p rocessing even at an oxygen level of 1160 wppm. The alloy has room tem perature ductility of 16% and superplastic elongation of 244% at 1000 degrees C. This alloy shows low intermediate temperature (600-850 degr ees C) ductility when tested in air. The vacuum testing revealed that the low ductility is associated within oxygen embrittlement phenomenon . It is expected that such an embrittlement can be reduced by an oxida tion resistant coating. The alloy also possesses superior strength to similar alloys in this class. Results of this investigation suggest a strong potential for consideration of this alloy to exceed the useful temperature range of nickel-based superalloys. (C) 1997 Elsevier Scien ce S.A.