Innovative processing to produce advanced intermetallic materials. Phase 1 final report

Technical Report · Fri Sep 01 04:00:00 EDT 1989

OSTI ID:6896122

Loutfy, R O

The program demonstrates the technical feasibility of synthesizing submicron titanium aluminide in a thermal rf plasma. Micron and submicron spherical titanium aluminide particles are produced in argon, hydrogen, and argon/hydrogen plasmas from the reaction of TiCl4(g), and Al(g). The ratio of Ti and Al is varied to produce the compounds Ti3Al, TiAl, and TiAl3. Microalloying with boron and macroalloying with niobium is demonstrated. Ti3Al whiskers can be produced, as well as other intermetallics of niobium aluminide, nickel aluminide, and molybdenum disilicide in the plasma synthesis process. Since submicron particles are produced, they have a high surface area and are sensitive to oxidation if not treated with a fugitive protective coating or utilized in a nonoxidizing atmosphere. Ti3Al particles are consolidated and utilized as a matrix for TiC and AlN composites. The submicron AlTi3 has significantly higher strength at room temperature than reported for commercial Ti3Al-11Nb alloy and useable strength is maintained up to 1000 C. The elongation is about the same as for commercial material because of possible oxide contamination in powder handling. However, dimpling and nacking is evident in the fracture surface, which suggests true room temperature ductility. Titanium aluminides have the potential to replace superalloys and become the dominant material for aerospace engines, air frames and skins for hypersonic vehicles.

• Research Organization: Materials and Electrochemical Research Corp., Tucson, AZ (United States)
• OSTI ID: 6896122
• Report Number(s): PB-93-158038/XAB; CNN: NSF-ISI88-60240
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101* -- Metals & Alloys-- Preparation & Fabrication
360103 -- Metals & Alloys-- Mechanical Properties
AEROSPACE INDUSTRY
ALLOY-NI49CR22FE18MO9
ALLOY-NI58CR20CO14MO4TI3
ALLOYS
ALUMINIUM ALLOYS
ARGON
BORON
BORON ADDITIONS
BORON ALLOYS
CHLORIDES
CHLORINE COMPOUNDS
CHROMIUM ALLOYS
COBALT ALLOYS
CORROSION RESISTANT ALLOYS
DUCTILITY
ELEMENTS
FABRICATION
FEASIBILITY STUDIES
FLUIDS
GASES
HALIDES
HALOGEN COMPOUNDS
HASTELLOY X
HASTELLOYS
HEAT RESISTANT MATERIALS
HEAT RESISTING ALLOYS
HYDROGEN
INDUSTRY
INTERMETALLIC COMPOUNDS
IRON ALLOYS
MATERIALS
MECHANICAL PROPERTIES
MOLYBDENUM ALLOYS
MOLYBDENUM COMPOUNDS
MOLYBDENUM SILICIDES
NICKEL ALLOYS
NICKEL BASE ALLOYS
NIOBIUM ALLOYS
NONMETALS
PLASMA
PROCESSING
RARE GASES
REFRACTORY METAL COMPOUNDS
SEMIMETALS
SILICIDES
SILICON COMPOUNDS
T
TENSILE PROPERTIES
TITANIUM ALLOYS
TITANIUM CHLORIDES
TITANIUM COMPOUNDS
TRANSITION ELEMENT COMPOUNDS
TUNGSTEN ADDITIONS
TUNGSTEN ALLOYS
WASPALOY