Corrosion - Metal Dusting

Metal Dusting

Metal dusting is a catastrophic form of corrosion that occurs when susceptible materials are exposed to environments with high carbon activities, such as synthesis gas and other high-CO environments. The corrosion manifests itself as a break-up of bulk metal to metal powder. The suspected mechanism is firstly the deposition of a graphite layer on the surface of the metal, usually from carbon monoxide (CO) in the vapour phase. This graphite layer is then thought to form metastable M₃C species (where M is the metal), which migrate away from the metal surface. However, in some regimes no M₃C species is observed indicating a direct transfer of metal atoms into the graphite layer.