Interface reactions in bilayers of aluminum and nickel-chromium alloy

Conference · Tue Dec 31 04:00:00 EST 1991

OSTI ID:10113786

Heald, S M; Tan, Zhengquan; Jayanetti, J K.D.

Glancing angle EXAFS and x-ray reflectivity are used to study the interface reaction between nickel-chromium alloys and aluminum. The two metals are found to react independently with Al, with the first reactions taking place at temperatures similar to those found for the pure metals. This means that Ni reacts first with Al to form NiAl{sub 3}, leaving behind a Cr-rich region at the interface. In this Cr-rich region some of the Cr transforms to the bcc structure from the fcc form of the alloy. At higher temperatures Cr reacts to form CrAl{sub 7}, and there is no evidence for ternary compound formation. Samples were also prepared with a controlled O contamination at the interface, and it inhibits the reaction much the same as for the pure metal cases. The Ni reaction is not identical to the pure sample case, since the presence of Cr slows down the reaction, and inhibits the initial reaction in the as-prepared bilayers.

• Research Organization: Brookhaven National Lab., Upton, NY (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: AC02-76CH00016
• OSTI ID: 10113786
• Report Number(s): BNL--46962; CONF-911202--27; ON: DE92005390
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102
ALUMINIUM
CHEMICAL REACTIONS
CHROMIUM ALLOYS
FINE STRUCTURE
INTERFACES
INTERMETALLIC COMPOUNDS
NICKEL ALLOYS
STRUCTURE AND PHASE STUDIES
X-RAY DIFFRACTION