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1.
The oxide films formed on AISI 304L stainless steel at 300 °C in the oxidation time range between 2 and 4 h have been studied by photoelectrochemistry. Photocurrents were investigated as a function of the wavelength of the incident light and the electrode potential. The investigation allowed the determination of the semiconductive properties of the oxides. The oxide films showed n-type behaviour. A duplex structure of the oxide films has been suggested on the basis of the photocurrent spectra, with an internal oxide layer having an optical gap (Eg2 = 2.16-2.3 eV) depending on the applied potential and oxidation time, higher to that of the external oxide layer (Eg1 ≈ 1.9 eV). Significant variations in the amplitude of the photocurrent were detected as a function of the applied potential and the oxidation time. 相似文献
2.
3.
设计了不同含量的稀土2Cr13不锈钢,采用扫描电子显微镜观察了不锈钢中稀土夹杂物的形态,并用动电位扫描法对其进行了极化曲线的测试。 相似文献
4.
载波钝化和钼酸盐后处理对不锈钢钝化膜性能的影响 总被引:1,自引:1,他引:1
一般认为交流电对金属的腐蚀过程具有加速作用,但我们发现,在直流电位基础上叠加适当波形、幅值和频率的交流电对不锈钢进行载波钝化,尔后再进行适当后处理可使钝化膜的稳定性提高,我们曾就不经后处理的载波钝化过程进行过探讨,本文着重探讨钼酸盐后处理对载波钝化膜表面状态和化学稳定性改善的作用机理。 相似文献
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The goal of this work was the development of a novel type of heterogeneous catalyst, consisting of bare metal nanoparticles
on stainless steel foils, which can be shaped to any kind of architecture and, if necessary, heated electrically. Solutions
of pre-prepared, ligand protected and monodispersed gold, palladium, platinum and rhodium nanoparticles were sprayed onto
stainless steel foils, followed by the careful removal of the ligand molecules by an oxygen plasma treatment. Due to this,
bare particles become irreversibly fixed on the steel support. It could be shown that the original particle sizes do not change
during the plasma treatment. Foils, densely coated with the nanoparticles, were used for gas phase catalyses in a self-made
reactor at room temperature or at 60 °C. Hydrogenation of 1,3-butadiene at 15 nm Pd and 2 nm Pt, CO oxidation at 16 nm, 8 nm
and 1.4 nm gold and NO reduction with NH3 at 2 nm Rh particles were performed, indicating that the novel catalysts might in principle be applicable in technical processes
if the experimental conditions like form and temperature would be optimized.
Dedicated to Professor Dieter Fenske on the occassion of his 65th birthday. 相似文献
7.
M.?Avramov Ivi?Email author J.?Popi? D.?Antonovi? 《Russian Journal of Electrochemistry》2005,41(3):270-274
Electrocatalytic properties of oxides formed at gold, platinum, and stainless steel electrodes in the malic acid electrooxidation in 0.1 M Na2SO4 are studied. Gas chromatographic analysis of the electrolyte after holding the potential at 1.0 V for 8 h shows that on platinum and gold electrodes 2 mmol of acetaldehyde are produced and on stainless steel, 45 mmol. The acetaldehyde yield is the highest on stainless steel.From Elektrokhimiya, Vol. 41, No. 3, 2005, pp. 304–309.Original English Text Copyright © 2005 by Avramov Ivi, Popi, Antonovi.This article was submitted by the authors in English. 相似文献
8.
研究了氢对不锈钢堆焊层熔合区的断裂韧性的影响作用。发现不锈钢堆焊层熔合区的断裂韧性随着充氢时间的增加而下降,结果表明,氢是引起加氢反应器不锈钢堆焊层剥离的主要因素。 相似文献
9.
Pedro de Lima Neto Mohamed Atik Luis A. Avaca Michel A. Aegerter 《Journal of Sol-Gel Science and Technology》1994,1(2):177-184
ZrO2 coatings deposited on 316 L stainless steel sheets were synthesized by sol-gel method using Zr(OC3H7)4 as precursor and isopropanol, glacial acetic acid, and water as solvents for application with ultrasounds. Different solutions for dip-coating were prepared with compositions varying between 0.025 and 0.9 mol/dm3 of ZrO2. X-ray diffraction shows that the films densified at 800°C are crystalline with a tetragonal structure. The thickness of the coatings varied from 0.35–0.75 m. The influence of the ZrO2 coatings on the corrosion behavior of stainless steel substrates in aqueous NaCl was studied through potentiodynamic polarization curves at 1 mV/s. The values of the electrochemical parameters allow for an explanation of the role of the films in the increased resistance of steel against corrosion in moderately aggressive environments. 相似文献
10.
M. Menning C. Schelle A. Duran J.J. Damborena M. Guglielmi G. Brusatin 《Journal of Sol-Gel Science and Technology》1998,13(1-3):717-722
Glass-like sol-gel coatings have been investigated as corrosion protective coatings on stainless steel. Magnesium- and borosilicate coatings with thickness of about 100–700 nm and methyl-modified SiO2 coatings with a thickness of about 2 m were deposited on stainless steel plates by dip-coating. The coatings were densified between 400°C and 500°C in different atmospheres (N2, air) for 1 h. The corrosion protection against gaseous attack was investigated by accelerated corrosion tests, at 800°C in air for 1 h. A corrosion protection factor was calculated from the relation Fe/Fe2O3, determined by XRD on the surface of coated and uncoated samples. Methyl-modified SiO2 coatings showed a protection factor, which was 2 orders of magnitude higher than for the other coatings. Electrochemical investigations were performed on samples submerged in a NaCl solution for 200 h. The corrosion propagation, polarization resistance and impedance vector were measured. For accelerated corrosion tests, polarization intensity curves were determined for high potentials of up to 1 V. Again excellent results were obtained for the methyl-modified SiO2 coatings, which remained passive for 200 h. Results of the salt spray corrosion test, however, showed no corrosion protection by the sol-gel coatings. After 2000 h in the salt spray chamber the steel was corroded and the coatings peeled off. It is concluded that for the further development of these coatings an improved interfacial passivation will be required. 相似文献