摘要
Composite coating on GH4169 alloy is prepared by laser cladding yttria-stabilized zirconia(YSZ)@Ni core-shell powdersmixed with NiCoCrAlY alloy powders.The cyclic oxidation behavior of the coatings,especially the growth process of theoxide layer,is investigated based on experimental research and first-principle calculations.The results indicate that theoxidation resistance of coated GH4169 alloy is beer than that of uncoated GH4169 alloy.The coating has three layers:acellular dendrite outer layer,a planar YSZ interlayer,and an inner layer composed of Cr2O3 formed during laser clading.After oxidation at 1000 and 1050℃,as the oxidation time increases,the cellular dendrite outer layer becomes thicker,andthe planar yttria-stabilized zirconia interlayer becomes thinner.Between the planar interlayer and Cr2O3 inner layer,and Al2O3 layer formed.Notably,cracks formed in the intcrface of Al2O3/Cr2O3 owing to thcir weak interface strength,whichled to the failure of the composite coating.
基金
supported by the National Natural Science Foundation of China(Grant No.51361026)
the Key Research and Development Plan of Jiangxi Province(Grant No.20181ACH80009)
the China Postdoctoral Science Foundation(GrantNo.2017M620576)
the Aeronautical Science Foundation of China(2017ZE56015)
the Open Foundation of the State Key Laboratory of Refractories and Metallurgy(Wuhan University of Science and Technology)(Grant No.G201808)
the Open Foundation of the State Key Laboratory of Advanced Refractories(Grant No.201806).
作者简介
Hai-zhong Zheng,zhznchu@126.com。
