The use of appropriate copper-based alloy coatings on structural compo
nents offers an avenue to minimize high temperature oxidation and exte
nd component life in an oxidizing environment. Cr2O3 Scales, similar t
o those formed on M-Cr (M = Ni, Co, Fe), would provide oxidation resis
tance for copper-based materials if they could form on a Cu-Cr coating
system. In the present study, three Cu-Cr coating compositions, i.e.
Cu-15vol.%Cr,Cu-30vol.%Cr and Cu-45vol.%Cr, were produced by codeposit
ion of copper and chromium on Cu-15vol.%Nb substrates. The oxidation k
inetics and oxide morphologies were characterized after exposure to ai
r at 649-degrees-C. The oxidation products of the Cu-15vol.%Cr coating
consisted primarily of copper oxides with discontinuous Cr2O3 scales.
A transition from discontinuous to continuous Cr2O3 scale formation o
ccurred between 15 and 30 vol.% Cr. For the Cu-30vol.%Cr and Cu-45vol.
%Cr coatings, protective Cr2O3 scales were formed which markedly reduc
ed the oxidation rates.