Aluminid/MCrAlY Beschichtungssystem

摘要

High temperature oxidation resistance of an aluminide diffusion overcoated MCrAlY coating system is substantially improved by CVD over-aluminizing the MCrAlY type overlay coating under CVD conditions that result in reduced concentrations of such tramp impurities as S and P in the aluminized MCrAlY overlay coating region of the coating system. The CVD aluminizing conditions yield an outwardly grown aluminide over-coat on the underlying MCrAlY type coating.