Effect of Y2O3 or CeO2 Fillers on the Oxidation Behavior of Aluminide Coatings by Low-temperature Pack Cementation

摘要:

利用Y2O3或CeO2纳米颗粒替代部分Al2O3粉作为填充剂，在Ni基体上, 于600 ℃低温渗铝10 h，制备了2种稀土氧化物改性的低温渗铝涂层。作为对比，采用相同的工艺在Ni基体上利用纯Al2O3粉制备了普通渗铝涂层。1000 ℃下恒温氧化结果表明：Y2O3通过抑制q-Al2O3的长大提高涂层的抗氧化性能，而CeO2则通过促进q-Al2O3向a-Al2O3的相变明显提高其抗氧化性能。文中对Y2O3或CeO2是如何影响渗铝涂层的氧化性能进行了分析。

Abstract:

Two aluminide coatings were produced on Ni substrate via a conventional pack-cementation at 600 oC for 10 h using Y2O3 or CeO2 particles instead of part of Al2O3 as filler. For comparison, aluminizing was also performed under the same condition using pure Al2O3 as filler. The results of isothermal-oxidation at 1000 oC indicate that Y2O3 can suppress the growth of q-alumina and improve the oxidation resistance, while CeO2 accelerates the q to a-alumina transformation and significantly improves the oxidation resistance. Besides, the effects of Y2O3 or CeO2 filler on the coating oxidation behavior were discussed.