A protected article includes a nickel-base superalloy substrate, an
interlayer overlying the substrate, and a protective layer overlying the
interlayer. The protective layer has a composition comprising at least one
of rhodium, platinum, palladium, and ruthenium. In one composition,
palladium is present in an amount of from about 1 to about 41 atomic
percent; platinum is present in an amount of about (40+atomic percent
palladium) atomic percent for palladium ranging from about 1 atomic
percent to about 14 atomic percent and up to about 54 atomic percent for
palladium ranging from about 15 atomic percent up to about 41 atomic
percent; rhodium is present in an amount of at least about 24 atomic
percent; zirconium, hafnium, titanium, and mixtures thereof are present in
an amount of from zero up to about 5 atomic percent; and ruthenium is
present in an amount of from zero up to about 5 atomic percent, balance
impurities. The interlayer has a coefficient of thermal expansion
intermediate between that of the substrate and that of the protective
layer. The protected article is fabricated by furnishing the substrate,
applying the interlayer over the substrate, and applying the protective
layer over the interlayer. The application of the protective layer may be,
for example, by welding or attachment of a solid piece.
