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101.
颜料体积浓度对水在醇酸涂层中传输行为的影响 总被引:9,自引:0,他引:9
水、离子和氧气是导致涂层下金属发生腐蚀的三个重要因素,它们在涂层中的传输过程对其下面金属的腐蚀会产生较大的影响,研究它们在涂层中的传输过程对于弄清涂层下金属发生腐蚀的机制至关重要 .研究表明 [1- 8], 水在涂层中的传输是一个扩散过程,分起始和饱和两个阶段;在起始阶段,随研究体系和实验条件的不同,水在涂层中的扩散过程遵循不同的规律,可能满足菲克第二扩散定律,也可能会发生较大的偏差 . 颜料与基料界面间的孔隙是水在涂层中传输的主要通道,调整颜料体积浓度( PVC)可以改变涂层中这种孔隙的数量和分布,从而… 相似文献
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Al2O3 coatings were obtained by the alkoxide route and deposited on stainless steel using the dip coating technique. The starting precursor was aluminum sec-butoxide modified by acrylic acid in order to prevent its precipitation in the presence of water.Useful information for the structural organization of alumina coatings on stainless steel is deduced from SIMS analysis. SIMS data reveal that the coating structure brings into play two different layers: an outer alumina layer that is more or less doped, mainly by iron, and an internal layer corresponding to the alumina/steel interphase. Beneath the interphase, the presence of an oxidized steel layer on the substrate surface is detected.Whatever the coating, the alumina/steel interphase exhibits a nearly constant thickness. On the other hand, a thickness variation of the oxidized steel layer is observed between samples under study: this thickness increases with the curing time of the coating. 相似文献
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Ellen Matthaei-Schulz Tony Flaherty Colm Flannery Tony Randles Odile Lefeuvre Pavel Zinin Laurent Robert 《Mikrochimica acta》2000,133(1-4):11-15
For quantitative assessment of the properties of hard coatings there is an increasing demand for testing methods with high
reliability of the test results, especially concerning the independence of the method and the comparability between different
laboratories. This includes the knowledge about all the factors which influence the test procedure itself, determination of
best testing conditions, testing of these conditions in round-robins to get a view of the comparability of results, and formulation
of guidelines for standardization. In a European project several test methods for hard coatings on steel were investigated
for this purpose and the elastic moduli of the coating and coating thickness were determined non-destructively by means of
quantitative acoustic microscopy. This method and the instruments available had not yet been certified in the fields of coatings
simply owing to the absence of standardised signal processing, followed by the determination of sound velocities and materials
parameter extraction. For this purpose four laboratories carried out investigations and measurements on reference samples
and on two types of hard coatings (titanium nitride and C-doped chromium) on M2 tool steel. 相似文献
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《Surface and interface analysis : SIA》2005,37(12):1082-1091
In this paper, we have studied, using X‐ray photoelectron spectroscopy (XPS), the chemical stability of TiN, TiAlN and AlN layers produced by magnetron sputtering on Si wafer substrates, against humid, SO2‐polluted atmospheres. The results have indicated that the TiN layers suffer almost no degradation after seven days of exposure to the aggressive environment. The degradation of the TiAlN layers is small, and this is evidenced by the appearance of signals corresponding to N? O bonds in the N 1s spectra, after seven days of exposure to the corrosive atmosphere and the increase in the Ti 2p spectra of the contribution corresponding to TiO2. In contrast, the degradation experienced by the AlN layers is quite large. The spectra reveal dramatic changes after just one day of exposure to the aggressive conditions. This is related to the preferential growth of the AlN layers, which gives rise to an open, columnar structure. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
109.
Stephen C. Hobaica 《Journal of Polymer Science.Polymer Physics》2003,41(8):807-822
Polyaniline is a member of the class of electrically conducting polymers, having possible commercial applications such as coatings. Aqueous‐based polyaniline coatings are preferred over organic solvent or concentrated strong acid based coatings because water is not a pollutant. The overall goal of this study was to further the development of water‐based polyaniline coatings by an examination of the effect of acidic water (pH 1.18) and air on polyaniline. Knowledge of the effect of water on the structure, molecular weight, electrical conductivity, and diffusion of the dopant assisted in ascertaining whether polyaniline degraded with water exposure. Knowledge of how Fourier transform infrared (FTIR) spectra would be affected by dry air was important for determining if polyaniline was chemically stable with time. The results showed that the molecular weight, ultraviolet–visible and FTIR spectra, and carbon‐to‐nitrogen molar ratio in the polymer backbone all remained unchanged during acidic water immersion. The constant nature of these physical parameters showed a high degree of water stability. A chloride ion diffusion coefficient of 2.8 to 85 × 10?9 cm2/h, the chloride concentration, and the electrical conductivity were also measured with the water immersion time. Aging polyaniline powders in a desiccator for 5 years showed no effect on the molecular structure, as indicated by the FTIR spectrum. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 807–822, 2003 相似文献
110.
对光盘用2P胶的应用研究进展情况进行了评述,其中光盘制备用光聚合浮雕成型2P胶的基本组成为各类多官能团丙烯酸酯类单体;光盘保护涂层用2P胶主要组分为环氧丙烯酸酯类预聚体。 相似文献