Metal dusting is "a catastrophic form of corrosion that occurs when susceptible materials are exposed to environments with high carbon activities.
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.
However, in some regimes no M3C species are observed indicating a direct transfer of metal atoms into the graphite layer.
Very briefly, there are several proposed methods for prevention or reduction of metal dusting; the most common seem to be aluminide coatings, alloying with copper and addition of steam.
[3] There is a significant amount of literature in existence that describes proposed mechanisms, prevention methods, etc.