| The turbine blades in aerospace are typically protected by a protective coating to improve the oxidation-resistant property of the substrate. Aluminized silicon coating has well oxidation-resistance. To addition rare-earth oxide Y2O3 in Aluminized silicon coating will have better oxidation-resistant than Aluminized silicon coating,it will improve the seizing which oxidizes the membrane, reduce the speed of oxidize increasing weight. Nickel-base superalloy k4104 was coated with two different coatings :A1-Si, Al-Si coating with Y2O3.According to GB/T133O3-91,the high temperature performance of these coatings have been studied by high temperature oxidation test under 1000℃ for 200h.Used Oringe to design the oxidation kinetics of the two coatings Discuss the oxidation-resistance of Al-Si-RE coating and the function mechanism of rare-earth oxide . Through to research the oxidation kinetics,we have the result that Al-Si coating with Y2O3 has the better anti-oxidation than Al-Si coating.Morphology and content of the coating were studied by SiRion SEM. Al2O3 is formed at the surface of the coating. The peeling of the coating at long time oxidation is obvious. But the new film of Al2O3 will form to protect the substrate.The morphology o f cross section is investigated by SEM and the thickness o f the film is also measured. The element profile in the coating and substrate can be researched by EDX. The Al- Si-RE coating has changed to Ni-rich and Al-rich β -NiAl which can improve the oxidation-resistance of the coating.To addition rare-earth oxide Y2O3 in Aluminized silicon coating will improve the seizing of α -Al2O3 and the base, reduce the stress of coating,and it is difficult for coating to fracture; it will reduce the speed of oxidize increasing weight; Joining of Y2O3 can also hinder the spread of each other, reduce the speed of dilution of Al in NiAl phase, lengthen the speed of degradation of the coating, improve the oxidation-resistance of the coating.
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