OXIDATION BEHAVIOR OF SIMPLE AND Pt-MODIFIED ALUMINIDE COATINGS ON IN738 AT 1100℃
铂改性铝化物涂层的高温氧化

The oxidation of both Iw and high-activity simple and Pt-modified aluminide coatings on nickel base superalloy IN738 has been studied in static air at llOOOC up to 1000 h. For all coatings oxidation followed a parabolic law up to 400 h. The M Pt-modified castings shaved better protectiveness with lower mass gains and snaller rate constants, especially for a long ten. The presence of Pt significantly improved the resistance to y'Ni,Al formation, pranoted selective oxidation of aluminum by preventing the transport of other elements outwards to A1,Q scale and resulted in the formation of purer, slaver-grawing and more adherent A1203 scales, delaying the onset of scale spalling for m types of coatings and of oxide nodules growth for the high aluminum activity coating.