杨久峰,舒小勇,董舒赫,汪云程,彭晓.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,WANG Yun-cheng,PENG Xiao.Oxidation Behaviors of Aluminized Coatings on K403 Ni-based Superalloy Prepared by Various Methods[J].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 |
| Oxidation Behaviors of Aluminized Coatings on K403 Ni-based Superalloy Prepared by Various Methods |
| |
| DOI：10.16490/j.cnki.issn.1001-3660.2023.06.028 |
| 中文关键词: 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 |
| 英文关键词:K403 aluminized coating packing cementation aluminizing slurry aluminizing CVD aluminizing oxidation performance |
| 基金项目: |
|
|
| Author | Institution |
| YANG Jiu-feng | School of Material Science and Engineering,Nanchang 330063, China |
| SHU Xiao-yong | School of Material Science and Engineering,Nanchang 330063, China |
| DONG Shu-he | School of Material Science and Engineering,Nanchang 330063, China |
| WANG Yun-cheng | China Aviation Development Southern Industry Co., Ltd., Hunan Zhuzhou 412002, China |
| PENG Xiao | School of Material Science and Engineering,Nanchang 330063, China ;Jiangxi Provincial Engineering Research Center for Surface Technology of Aeronautical Materials, Nanchang Hangkong University, Nanchang 330063, China |
|
| 摘要点击次数: |
| 全文下载次数: |
| 中文摘要: |
| 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 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 采用SA、PCA、CVD 3种方法扩散渗Al，均获得了β–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SA>CVD>PCA。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θ–Al2O3向稳态α–Al2O3的转变过程发生了变化。在氧化时，PCA渗Al涂层快速生长θ–Al2O3膜，适量Ti的掺杂致使CVD渗层α–Al2O3膜快速形成。虽然SA渗Al涂层在多数地方生长α–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 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β–NiAl涂层的氧化机制发生变化。 |
| 英文摘要: |
| Diffusion aluminized coating can grow protective Al2O3 film with high thermal stability, density and slow growth 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 mm×10 mm×2 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 μm 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 β-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 β-NiAl coating's oxidation behavior, in particular, the phase transformation of meta-stable θ-Al2O3 to stable α-Al2O3. Different from the aluminized coating prepared by PCA which grew a θ-Al2O3 scale, the CVD counterpart with an appropriate concentration of incorporated Ti directly formed a more compact α-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 α-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 β-NiAl diffusion coatings and the oxide scales on them is discussed. |
| 查看全文 查看/发表评论 下载PDF阅读器 |
| 关闭 |
|
|
|
渝公网安备 50010702501715号