Development of ductile Nb-Ti-Al alloys: perspective and selected successes

Book · Sat Dec 30 23:00:00 EST 1995

OSTI ID:233988

Loria, E A ^[1]

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1. Niobium Products Co., Inc., Pittsburgh, PA (United States)

An introduction is presented on the development of certain Nb-Ti-Al alloys which have been classified within the spectrum of advanced intermetallic materials but which are unique in that they are ductile alloys. Their lower density and higher temperature capability compared to present aerospace materials provide for a lighter weight component, with structural integrity, which would receive added protection from a suitable metallic coating. The compositional boundaries for Nb-Ti-Al-Cr alloys that provide ductility and strength are described, with emphasis placed on 40Nb-40Ti-10Al-10Cr (at pct) as a suitable base for alloy development. Results show attractive oxidation and oxygen embrittlement resistance compared to existing Nb-based alloys, as well as good tensile yield strength and ductility up to 1200 C, thereby exceeding the use temperature of Ni-based alloys. Initial results reveal that strengthening for high temperature service can be improved via appropriate additions of Cr, Hf and certain refractory elements. Following this sequence, the first commercial-scale production of the base alloy and a more complex alloy containing 44Nb-35Ti-6Al-5Cr-8V-1W-0.5Mo-0.3Hf (at pct) is described, along with mechanical properties.

• OSTI ID: 233988
• Report Number(s): CONF-950908--; ISBN 0-87170-539-7
• Country of Publication: United States
• Language: English

Related Subjects

33 ADVANCED PROPULSION SYSTEMS
36 MATERIALS SCIENCE
AIRCRAFT COMPONENTS
ALUMINIUM ALLOYS
CARBON ADDITIONS
CHEMICAL COMPOSITION
CHROMIUM ALLOYS
CREEP
ELONGATION
EXPERIMENTAL DATA
EXTRUSION
FABRICATION
HAFNIUM ADDITIONS
INTERMETALLIC COMPOUNDS
INTERSTITIALS
MATERIALS
MECHANICAL PROPERTIES
MELTING
MOLYBDENUM ADDITIONS
NIOBIUM ALLOYS
OXIDATION
TENSILE PROPERTIES
TITANIUM ALLOYS
TUNGSTEN ALLOYS
VANADIUM ALLOYS
YIELD STRENGTH