Alloy compositions which are resistant to
metal dusting
corrosion are provided by the present invention. Also provided are methods for preventing
metal dusting on
metal surfaces exposed to carbon supersaturated environments. The
alloy compositions include an
alloy (PQR), and a multi-layer
oxide film on the surface of the
alloy (PQR). The alloy (PQR) includes a metal (P) selected from the group consisting of Fe, Ni, Co, and mixtures thereof, an alloying metal (Q) comprising Cr, Mn, and either Al, Si, or Al / Si, and an alloying element (R). When the alloying metal (Q) includes Al, the multi-layer
oxide film on the surface of the alloy includes at least three
oxide layers. When the alloying metal (Q) includes Si, the multi-layer oxide film on the surface of the alloy (PQR) includes at least four oxide
layers. When the alloying metal (Q) includes Al and Si, the multi-layer oxide film on the surface of the alloy (PQR) includes at least three oxide
layers. The multi-layer oxide film is formed in situ during use of the
alloy composition in a carbon supersaturated
metal dusting environment. Advantages exhibited by the disclosed alloy compositions include improved
metal dusting corrosion resistance at high temperatures in carbon-supersaturated environments having relatively
low oxygen partial pressures. The disclosed alloy compositions are suitable for use as the inner surfaces in reactor systems and
refinery apparatus.