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21.
Low-energy electron diffraction (LEED), Auger electron spectroscopy and X-ray photoelectron spectroscopy (XPS) investigations of both the growth of an iron film on silicon (100) at room temperature and the subsequent formation of iron silicide are the subjects of this paper. An in-situ cleaned silicon (100) wafer without carbon or oxygen contamination exhibiting the known 2 × 1 reconstruction in the LEED pattern served as the substrate. Iron was deposited on this reconstructed surface at 300 K. The comparison of theoretical calculations based on three growth mechanisms with XPS data obtained with take-off angles of 0° and 50° clearly demonstrates a layer-by-layer growth of the iron film on silicon (100). At 300 K no formation of iron silicide was observed, although an interaction between iron and silicon could be detected at the interface. The formation of iron silicide was observed at annealing temperatures of 630–730 K. Quantitative XPS analysis yields the presence of FeSi2, when the thickness is large enough. Neither the iron film on silicon nor the silicide shows any LEED pattern. 相似文献
22.
Motofumi Suzuki Kohei Kinoshita Shinji Jomori Hidehiko Harada Kaoru Nakajima Kenji Kimura 《Thin solid films》2007,515(22):8281-8284
The initial stage of iron silicide formation is investigated by high-resolution Rutherford backscattering spectroscopy. During the Fe deposition on Si(001) at 470 °C, the formation of FeSi2 is confirmed by the surface peak analysis. Initially, FeSi2 grows epitaxially so that one of the major crystallographic axes is parallel to the <111> axis of the Si substrate. With increasing Fe deposition, the deviation between the major crystallographic axis of the silicide region and Si<111> increases although the electron diffraction pattern is independent of the amount of Fe deposition. Therefore, the subsurface crystallographic structure of iron silicide is transformed from a cubic-like to a low-symmetry structure. 相似文献
23.
I.L. Lehr 《Corrosion Science》2007,49(5):2210-2225
This work is a study of the electropolymerisation of pyrrole onto iron electrodes in the presence of sodium bis(2-ethylhexyl) sulfosuccinate in a wide pH interval. The characterisation of the films was done using electrochemical techniques, SEM/EDX and IR spectroscopy. We show that it is possible to synthesise homogeneous, adherent and very compact films in the pH range between 7 and 12 under potentiodynamic, galvanostatic and potentiostatic conditions without substrate dissolution. The effects of various parameters on electrodeposition were investigated. The new procedure for the electrochemical synthesis of polypyrrole results in improved anticorrosion properties. The inhibition is proposed to be due to the sum of a repulsion of chloride ions because AOT remains entrapped in the polymer matrix and the presence of the iron oxide. Advantages of the use of surfactants in the electropolymerisation solution are discussed. 相似文献
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简述了攀钢含铁尘泥的基本特性、攀钢含铁尘泥利用技术现状及存在的问题。根据目前国内外钢铁企业含铁尘泥综合利用技术的动态、经验,并结合攀钢的实际情况,提出了攀钢含铁尘泥利用技术的发展方向。 相似文献
29.
Susil K. Putatunda 《Materials and Manufacturing Processes》2003,18(4):667-684
An investigation was carried out to examine the influence of microstructure on the stress corrosion cracking (SCC) growth behavior of an austempered high-carbon (1.00%), high-silicon (3.00%), and high-manganese (2.00%) cast steel. Compact tension specimens were prepared from this cast steel as per American Society for Testing Materials standard E-399 and were given four different heat treatments to produce different microstructures. The SCC behavior of these specimens was studied in 3.5% NaCl solution. The test results indicate the KISCCvalue of the material increases as the austenite content increases. Significant improvement in SCC resistance was achieved by using a novel two-step austempering process. Intergranular crack growth was observed in all these specimens. 相似文献
30.
微量稀土元素在铸钢中的应用 总被引:5,自引:0,他引:5
综述了近几年稀土在铸钢中的应用研究现状 ,分析了稀土在铸钢中的作用机理及对铸钢性能的影响 ,指出了铸钢中加入稀土的原则 ,提出了今后的研究方向 相似文献