Oxidation and Thermal Shock Behavior of a Glass-Alumina Composite Coating on K38G Superalloy at 1000℃

Minghui Chen,Mingli Shen,Xin Wang,Shenglong Zhu and Fuhui Wang State Key Laboratory for Corrosion and Protection,Institute of Metal Research,Chinese Academy of Sciences,Shenyang 110016,China

摘 要：The glass-alumina composite coatings were successfully prepared on the K38G superalloy substrates.Their isothermal oxidation and thermal shock behavior at 1000 ℃ were characterized.With a post-annealing process at 850 ℃,the composite coatings possessed an improved protective effect for the alloy substrates from isothermal oxidation and a higher resistance to thermal shock.Crystallization from the glass matrix and interfacial reaction between the matrix and alumina inclusions,which caused the composites more refractory and tough,accounted for this improvement.The micromechanisms for the formation of oxidation results of spinel ZnCr₂O₄ were also discussed.

关键词：