表面技术2025，Vol.54Issue(24)：128-137,10.DOI:10.16490/j.cnki.issn.1001-3660.2025.24.010
Y掺杂NiAlHf涂层在1150℃下的微观结构演变和抗氧化性能研究
Microstructure Evolution and Oxidation Resistance of Y-doped NiAlHf Coatings at 1 150℃
摘要
Abstract
It has been demonstrated that NiAl high-temperature protective coatings have the capacity to enhance the surface temperature tolerance of materials utilized in the hot-section components of aero-engines to a considerable extent.Among these,Hf-modified NiAl coatings have been shown to enhance oxidation resistance and extend the service life of the coatings.Nevertheless,the enhancement of oxidation resistance achieved through the doping of a single rare earth element remains constrained.The present study investigated the influence of Y doping on the microstructural evolution and oxidation resistance of NiAlHf coatings at 1 150℃.The NiAlHf/Y coatings were deposited on cylindrical nickel-based single-crystal superalloy samples with a diameter of 16 mm and thickness of 2 mm using the arc ion plating(AIP)technique.The as-deposited samples were then subject to isothermal annealing at 900℃and 5×10-2 Pa for a duration of 4 h.This was followed by isothermal oxidation experiments at 1 150℃for 200 h.The phase composition of the oxide layers was analyzed by XRD,while the surface and cross-sectional morphologies and elemental distribution of the coatings were systematically characterized with a SEM equipped with an EDS.The results showed that,in the early stages of oxidation,a large number of radioactive cracks appear on the surface of the NiAlHf coating.In contrast,the NiAlHfY coating formed a more continuous,flat Al2O3 layer.This difference was due to the fact that Hf and Y co-doping could slow down the transformation of θ-Al2O3 to α-Al2O3,thereby reducing stresses in the oxidized layer.In NiAlHf coatings,HfO2 was primarily found at the oxide/coating interface and within the coating.In contrast,in NiAlHfY coatings,HfO2 was predominantly present in the oxide layer and distributed along the Al2O3 grain boundaries.Meanwhile,Y was uniformly distributed within the oxide layer,with Y bias observed in the interdiffusion zone at the coating/substrate interface.Analysis of the oxidation dynamic curve showed that the oxidation weight gain of the two coatings followed a parabolic trend when the oxidation duration was less than 75 h and a linear trend when it was greater than 75 h.It also revealed the presence of a multilayered structure consisting of mixed oxides,such as Al2O3,NiAl2O4 and NiO,with a higher concentration of refractory elemental oxides in the oxidized layer.Furthermore,the NiAlHf coating exhibited an average oxidation rate of 0.122 34 g/(m2·h)at 1 150℃for 200 h,while the NiAlHfY coating showed a lower rate of 0.113 88 g/(m2·h).Moreover,the β-NiAl phase consumption was found to be slower in the NiAlHfY coating,thus demonstrating its superior protective capability for the substrate.In conclusion,the presence of Y in NiAlHf coating has a further reducing effect on the growth rate of the oxide layer.In addition,the adhesion of the coating is improved,and the antioxidant properties are made more effective.These findings provide a solid foundation for the further development and industrial application of the future high-temperature protective coating system.关键词
NiAlHf涂层/NiAlHfY涂层/活性元素掺杂/微观结构演变/高温抗氧化性能Key words
NiAlHf coating/NiAlHfY coating/reactive element doping/microstructural evolution/high-temperature oxidation resistance分类
矿业与冶金引用本文复制引用
陈振鹏,杨尚琴,苏鹏,杨洪志..Y掺杂NiAlHf涂层在1150℃下的微观结构演变和抗氧化性能研究[J].表面技术,2025,54(24):128-137,10.基金项目
国家自然科学基金项目(52401115)The National Natural Science Foundation of China(52401115) （52401115）
