摘要
研究镍基高温合金的高铝与低铝活度简单涂层和铂改性渗铝涂层在 1 1 0 0℃空气中的氧化行为 .在 40 0h内 ,各涂层的氧化均遵循抛物线规律 .两种铂铝涂层显示出良好的保护性 ,经 1 0 0 0h氧化后 ,只有较小的增重和较小的抛物线速率常数 .Pt的存在 ,通过阻止合金元素穿过Al2 O3 膜向外扩散 ,形成更纯的、结合力更好的Al2 O3 膜 .并且 ,Pt的存在抑制γ′ Ni3 Al相的形成 ,推迟涂层的高温退化和高铝活度涂层中非铝氧化瘤的生长 .
The oxidation of both low and high\|activity simple and Pt\|modified aluminide coatings on nickel base superalloy IN738 has been studied in static air at 1100℃ up to 1000 h. For all coatings oxidation followed a parabolic law up to 400 h. The two Pt\|modified costings showed better protectiveness with lower mass gains and smaller rate constants, especially for a long term. The presence of Pt significantly improved the resistance to γ′\|Ni 3Al formation, promoted selective oxidation of aluminum by preventing the transport of other elements outwards to Al 2O 3 scale and resulted in the formation of purer, slower\|growing and more adherent Al 2O 3 scales, delaying the onset of scale spalling for two types of coatings and of oxide nodules growth for the high aluminum activity coating.
出处
《腐蚀科学与防护技术》
CAS
CSCD
2000年第2期63-67,共5页
Corrosion Science and Protection Technology
基金
国家自然科学基金!资助项目 (5972 510 1)
