通过电弧离子镀制备了NiCrAlYRe和NiCrAlY涂层，经真空热处理后涂层均由γ´-Ni3Al、γ-Ni、 β-NiAl和α-Cr四相构成。在NiCrAlYRe涂层中，Re主要存在于α-Cr相，Re促进了α-Cr相在涂层中的析出，并提高了α-Cr在长期氧化过程中的稳定性，特别在氧化膜/涂层界面上析出了大量富Re的α-Cr。由于富Re的α-Cr 同α-Al2O3具有极为接近的热膨胀系数，降低了氧化膜中的热应力，提高了NiCrAlY 涂层表面抗剥落能力。添加Re明显提高了NiCrAlY涂层在900℃90%Na2SO4+ 10%K2SO4介质中的抗热腐蚀性能。
Arc ion plating (AIP) was used to produce NiCrAlY and NiCrAlYRe overlay coatings. After heat treatment in vacuum, both of the coatings consisted of γ‘-Ni3Al, γ-Ni, β-NiAl and α-Cr. Re in the NiCrAlYRe coating existed in α-Cr and promoted the precipitation and thermal stability of α-Cr. The existence of α-Cr in the interface of coating and substrate lowered coefficient of thermal expansion and thus reduced thermal stress in the surface scale, improving adherence of the scale. The addition of Re obviously increased hot corrosion resistance of NiCrAlY in 90%Na2SO4+10 mass%K2SO4.
参考文献
| [1] | Taylor M P, Evans H E. Formation of diffusion cells in LPPS MCrAlY coatings [J]. Mater. High Temp., 2000, 20: 461-466[2] Wood G C. Fundamental factors determining the mode of scaling of heat resistant alloys [J]. Werkst. Korros, 1971, 22:491-503 [3]Luthra K L, Briant C L. Surface segregation in M-Cr-Al-Y alloys [J].Metall. Trans., 1988, 19A: 923-938[4]Smeggil J G, Funkenbusch A W, Bornstein N S. A relationship between indigenous impurity elements and protective oxide scale adherence characteristics [J]. Metall.Trans., 1986, 17A: 923-938[5]Clemens D, Nickel H.TEM and SEM studies of protective alumina scale on NiCrAlY alloys [J]. J. Anal. Chem.,1996, 355: 703-706[6] Saunders S R J, Nicholls J R. Hot salt corrosion test procedures and coating evaluation [J]. Thin Solid Film, 1984, 119:247-269[7]Czech N, Schmitz F, Stamm W.Microstructural analysis of the role of rhenium in advanced MCrAlY coatings [J]. Surf. Coat. Technol., 1995, 7: 28-33[8] Beele W, Czech N, Quadakkers W J, et al. Long-term oxidation tests on a re-containing MCrAlY coating [J]. Surf. Coat. Technol, 1997, 94/95:41-45[9] Otsuka N, Rapp R A. Effect of chromate and vanadate anions on the hot corrosion of preoxidized Ni by a thin fused Na2SO4 film at 900℃ [J]. J. Electrochem. Soc, 1990, 137:53-60[10] Johnson J B, Nicholls J R, Hurst R C, et al. The mechanical properties of surface scale on nickel-base superalloys-ⅡContaminate corrosion [J]. Corros. Sci, 1978, 18:543-553[11] McKee D W, Shores D A, Lurthra K L. The effect of SO2 and NaCl on high temperature hot corrosion [J]. J. Electrochem. Soc, 1978, 125(3):411-419[12] Xiong Y L, Wood S A. Experimental determination of the solubility of ReO2 and the dominant oxidation state of rhenium in hydrothermal solutions [J]. Chem. Geol, 1999, 158:245-256[13]Karunaratne M S A, Reed R C. Interdiffusion of the platinum-group metals in nickel at elevated temperature [J]. Acta Mater., 2003,51: 2905-2911[14] Liu C T, Sun X F, Guan H R, et al. Effect of rhenium addition to a nickel-base single crystal superalloy on isothermal oxidation of the aluminide coating [J]. Surf. Coat.Technol, 2005, 194:111-118 |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%