Chromia-forming alloys metal dusting

As discussed in Section 5.5, chromia forming alloys that are widely considered for use in metal dusting environments suffer from the fact that in many cases a fully protective surface oxide is unable to form, or defected regions in the oxide are unable to reheal themselves for kinetic reasons. While high chromium ferritic alloys exhibit a better tendency for protective chromia film formation, the poor mechanical properties of such alloys render them unsuitable as bulk... 

It was discussed in Section 5.5 that a primary reason why many chromia forming alloys, even with relatively high Cr concentrations, are susceptible to metal dusting is related to the paucity of achieving full surface coverage... 

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