不同方法制备K403镍基高温合金渗铝层的氧化行为研究_杨久峰.pdf

第 52 卷 第 6 期 表面技术 2023 年 6 月 SURFACE TECHNOLOGY 319 收稿日期：20220526；修订日期：20221031 Received：2022-05-26；Revised：2022-10-31 作者简介：杨久峰（1997），男，硕士生。Biography：YANG Jiu-feng(1996-),Male,Master.通讯作者：舒小勇（1983），男，博士。Corresponding author：SHU Xiao-yong(1983-),Male,Doctor.引文格式：杨久峰,舒小勇,董舒赫,等.不同方法制备 K403 镍基高温合金渗铝层的氧化行为研究J.表面技术,2023,52(6):319-326.YANG Jiu-feng,SHU Xiao-yong,DONG Shu-he,et al.Oxidation Behaviors of Aluminized Coatings on K403 Ni-based Superalloy Prepared by Various MethodsJ.Surface Technology,2023,52(6):319-326.不同方法制备 K403 镍基高温合金渗铝层的 氧化行为研究 杨久峰1a，舒小勇1a，董舒赫1a，汪云程2，彭晓1a,1b（1.南昌航空大学 a.材料科学与工程学院 b.江西省航空材料表面技术工程研究中心，南昌 330063；2.中国航发南方工业有限公司，湖南 株洲 412002）摘要：目的目的 研究采用包埋渗（PCA）、料浆渗（SA）和化学气相沉积（CVD）3 种方法，在 Ni 基高温合金K403 上制备渗 Al 涂层的成分和结构差异及其对氧化行为的影响，为采用相关方法制备高性能渗 Al 涂层提供理论和实验指导。方法方法 在 K403 上，采用 3 种方法在 950 下扩散渗 Al，通过带能谱仪（EDS）的扫描电镜（SEM）、X 射线衍射（XRD）和热重分析仪（TGA）分析不同方法制备的渗 Al 涂层的成分变化情况，以及对 Al2O3生长机制的影响。结果结果 采用 SA、PCA、CVD 3 种方法扩散渗 Al，均获得了 NiAl 涂层，其中来自 K403 合金基体元素（尤其是 Ti）的掺杂情况各不相同，掺杂浓度按照涂层制备方法排列顺序为SACVDPCA。在 1 000 空气中恒温氧化，结果表明，CVD 渗 Al 涂层的氧化速度最慢，PCA 最快，SA居中。这是由于 Ti 的掺杂水平不同，导致涂层的氧化行为，尤其是亚稳态 Al2O3向稳态 Al2O3的转变过程发生了变化。在氧化时，PCA 渗 Al 涂层快速生长 Al2O3膜，适量 Ti 的掺杂致使 CVD 渗层 Al2O3膜快速形成。虽然 SA 渗 Al 涂层在多数地方生长 Al2O3膜，但过量 Ti 掺杂导致渗层析出较多大尺寸富 Ti相，快速外氧化和内氧化使得涂层的总氧化速度居于另 2 种涂层之间。结论结论 在 K403 上采用不同方法渗 Al，合金元素的掺杂水平不同，使得制备的 NiAl 涂层的氧化机制发生变化。关键词：K403；渗 Al 涂层；包埋渗 Al；料浆渗 Al；化学气相沉积渗 Al；氧化性能 中图分类号：TG178 文献标识码：A 文章编号：1001-3660(2023)06-0319-08 DOI：10.16490/ki.issn.1001-3660.2023.06.028 Oxidation Behaviors of Aluminized Coatings on K403 Ni-based Superalloy Prepared by Various Methods YANG Jiu-feng1a,SHU Xiao-yong1a,DONG Shu-he1a,WANG Yun-cheng2,PENG Xiao1a,1b(1.a.School of Material Science and Engineering,b.Jiangxi Provincial Engineering Research Center for Surface Technology of Aeronautical Materials,Nanchang Hangkong University,Nanchang 330063,China;2.China Aviation Development Southern Industry Co.,Ltd.,Hunan Zhuzhou 412002,China)ABSTRACT:Diffusion aluminized coating can grow protective Al2O3 film with high thermal stability,density and slow growth 320 表 面 技 术 2023 年 6 月 speed in high temperature environment,which is widely against the high temperature oxidation to increase the life and protect the surface.Slurry aluminizing(SA),packing cementation aluminizing(PCA),and chemical vapor deposition(CVD)are three typical methods for preparing aluminized coating.Different coating structures and compositions can be obtained by different aluminized preparation methods,which may lead to difference in high temperature oxidation properties.To explore this difference,a Ni-based superalloy K403 was subject to diffusional aluminizing by three typical methods,and the oxidation resistance were evaluated.The K403 alloy was cut into long squares of 20 mm10 mm2 mm as the base materials and was smoothed by sandpaper and then cleaned.By employing methods of SA,PCA,and CVD respectively at 950,the diffusional aluminized coatings with about 40-60 m thickness were prepared.High temperature oxidation tests were performed by the SETSYS evolution thermo-gravimetric analyzer(for in situ recording oxidation curves)in the air at 1 000 for 50 h.Then the surface and cross-sectional microstructure of the coating were observed with a scanning electron microscope(FEI Nova Nano SEM450).Then the component was analyzed by a energy dispersive X-ray spectroscopy(EDS)of each selected point taken by an energy spectrometer.The phase composition of the coating was analyzed by an X-ray diffractometer(D8ADVANCE-A25).The aluminized coatings available at 950 oC by various methods were all composed of-NiAl phase.However,the concentration of metals particularly Ti diffused into the coating from K403 was method dependent,with variation of the concentration of incorporated metal from high to low in order as follows:slurry aluminization(SA),pack cementation aluminization(PCA)and CVD aluminization.Oxidation in air at 1 000 showed that the aluminized coating prepared by PCA had the fastest oxidation rate,the CVD counterpart had the slowest,and the SA one was in the middle.The result was attributed to the difference in the concentration of the incorporated Ti,which could affect the-NiAl coatings oxidation behavior,in particular,the phase transformation of meta-stable-Al2O3 to stable-Al2O3.Different from the aluminized coating prepared by PCA which grew a-Al2O3 scale,the CVD counterpart with an appropriate concentration of incorporated Ti directly formed a more compact-Al2O3 scale during oxidation.The incorporation of too much Ti into the aluminized coating prepared by SA lead to the precipitation of more large-sized Ti-rich phases.Its faster external and internal oxidation caused the coating,although it grew-Al2O3 scale on major area,to have the oxidation rate slower than the aluminized coating prepared by PCA but faster than the CVD one.The dependence of the various aluminizing methods on the mechanisms for the growth of-NiAl diffusion coatings and the oxide scales on them is discussed.KEY WORDS:K403;aluminized coating