Preparation of ductile nickel aluminides for high-temperature uses. [Doping with 500 ppM boron]

Technical Report · Sat Jan 01 00:00:00 UTC 1983

OSTI ID:6210578

Liu, C T; Koch, C C; White, C L

Intermetallic compounds based on nickel and iron aluminides are attractive for structural applications at elevated temperatures. The strong tendency for long range order in these alloys reduces the atomic mobility at elevated temperatures and results in good structural stability and resistance to high-temperature deformation. The major difficulty with using aluminides, such as Ni/sub 3/Al, as structural materials, however, is their tendency for reported brittle intergranular fracture at low temperatures. This brittleness, which effectively precludes fabrication into most structural components, is extremely sensitive to minor variation in alloy preparation. Recent studies have demonstrated that small boron additions greatly improve the ductility of polycrystalline Ni/sub 3/Al. This paper describes a systematic study of microalloying and stoichiometry effects on preparation and fabrication of ductile nickel aluminides. Emphasis is also placed on understanding the chemical aspects of microalloying elements (dopants) on composition and cohesion of grain boundaries in Ni/sub 3/Al.

• Research Organization: Oak Ridge National Lab., TN (USA)
• DOE Contract Number: W-7405-ENG-26
• OSTI ID: 6210578
• Report Number(s): CONF-830541-2; ON: DE83012579
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360101* -- Metals & Alloys-- Preparation & Fabrication
ALLOYS
ALUMINIUM ALLOYS
BORON ADDITIONS
BORON ALLOYS
DUCTILITY
FABRICATION
INTERMETALLIC COMPOUNDS
MECHANICAL PROPERTIES
METALLURGICAL EFFECTS
NICKEL ALLOYS
NICKEL BASE ALLOYS
TENSILE PROPERTIES