OXIDATION BEHAVIOUR OF NiAl(Si)+CeO_2 TYPE HIGH TEMPERATURE COATING
NiAl(Si)+CeO_2型高温涂层氧化行为的研究

The oxidation behaviour of a NiAl(Si)-type high temperature coating with dispersed ceria prepared by a composite technique was compared with several kinds of aluminide or silicoaluminide coatings. The effect of ceria and silicon on the oxidation resistances of the coatings were studied emphatically. It was revealed that most of Si-rich secondary phases dispersed in the inner part of the coating and only a little Si solved in NiAI phase; in addition silicon content in silicoaluminizing coating on the alloy itself was much higher than that in the composite coating. The results of oxidation tests indicated that the oxidation rates of the coatings may be effectively reduced by adding ceria and silicon; the adhesion of scaie was improved markedly by the addition of ceria, especially by simultaneous addition of both ceria and silicon.