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971.
采用Davanathan-Stachursky双电池渗氢装置研究了X120试验管线钢中电化学氢渗透动力学行为,运用电化学充氢方法对X120管线钢进行预制微裂纹,采用SEM观察钢中夹杂物及其与氢致裂纹(HIC)形成的关系。 实验结果表明,随着充氢电流密度的增大,饱和阳极电流I∞、氢扩散通量J∞、氢有效扩散系数Deff均逐渐增大;HIC萌生与钢中夹杂物化学成分有关,X120管线钢中主要含有Al、Mn的硫化物、氧化物夹杂,氮化钛、铌的复合夹杂以及Ca-Al-O-S的混合物夹杂,HIC更易于在含Al、Mn的夹杂物处萌生及形成,且裂纹形核后一般沿轧制方向生长。 相似文献
972.
聚苯胺水性涂料的制备及其防腐性能 总被引:2,自引:0,他引:2
将有机磷酸(乙二醇单甲醚磷酸酯和乙二醇单甲醚磷酸二酯混合物)(OP)掺杂得到的导电聚苯胺(PANI-OP)加入到水性环氧树脂(WER)中,制备了聚苯胺水性防腐涂料,并且研究了其防腐蚀性能和防腐蚀机理。 透射电子显微镜观察表明,导电聚苯胺质量分数为0.1%时,其粒径分布范围为50~100 nm。 电化学阻抗谱以及开路电压的变化表明,聚苯胺的存在显著提高了涂层的防腐效果。 金属基底光电子能谱结果表明,聚苯胺水性涂料良好的防腐性能缘于在金属表面生成了致密的氧化物膜以及掺杂剂离子与溶解金属生成了不溶性的盐。 相似文献
973.
A. V. Gromova Yu. F. Ivanov S. V. Vorob’ev S. V. Konovalov O. V. Sosnin 《Russian Physics Journal》2009,52(3):265-268
Methods of transmission electron microscopy of thin foils are used to study the evolution of dislocation substructures in
Fe–0.1C–1.7Mn–0.92Ti–18.2Cr–10.4Ni–0.71Si corrosion-proof austenitic steel subject to high-cycle fatigue loading to destruction.
Quantitative dependences of the dislocation substructure parameters on the number of loading cycles and distances to the sample
surface are established.
Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 3, pp. 42–45, March, 2009. 相似文献
974.
975.
Abstract The effect of sodium benzoate (SB) and sodium 4-(phenylamino)benzenesulfonate (SPABS) on the corrosion behavior of low carbon
steel has been investigated using gravimetric method in the temperature range of 30–80 °C, velocity range of 1.44–2.02 m s−1 and concentration range of 6.94 × 10−4 to 4.16 × 10−3 mol dm−3 SB and 3.69 × 10−4 to 2.06 × 10−3 mol dm−3 SPABS. Optimization of temperature, fluid velocity, and inhibitors concentration has been made. The obtained results indicate
that the inhibition efficiency (w
IE %) at 1.56 m s−1 is not in excess of 81.5% at 4.16 × 10−3 mol dm−3 SB and 84.4% at 2.06 × 10−3 mol dm−3 SPABS. The inhibitive performance of these compounds showed an improvement with increasing concentration up to critical values
of SB and SPABS; beyond these concentrations no further effectiveness is observed. These inhibitors retard the anodic dissolution
of low carbon steel by protective layer bonding on the metal surface. The adsorption of SB and SPABS on the low carbon steel
surface was found to obey the Freundlich isotherm model. The FT-IR spectroscopy was used to analyze the surface adsorbed film.
Graphical abstract Low carbon steel corrosion in presence of sodium benzoate and sodium 4-(phenylamino)benzenesulfonate has been investigated.
The adsorption mechanism obeyed Freundlich isotherm model. FT-IR was used to analyze the adsorbed film
相似文献
976.
977.
An experimental approach based on Digital Image Correlation (DIC) is successfully applied to predict the uniaxial stress-strain response of 304 stainless steel specimens subjected to nominally uniform temperatures ranging from room temperature to 900 °C. A portable induction heating device equipped with custom made water-cooled copper coils is used to heat the specimen. The induction heater is used in conjunction with a conventional tensile frame to enable high temperature tension experiments. A stereovision camera system equipped with appropriate band pass filters is employed to facilitate the study of full-field deformation response of the material at elevated temperatures. Using the temperature and load histories along with the full-field strain data, a Virtual Fields Method (VFM) based approach is implemented to identify constitutive parameters governing the plastic deformation of the material at high temperature conditions. Results from these experiments confirm that the proposed method can be used to measure the full field deformation of materials subjected to thermo-mechanical loading. 相似文献
978.
Coatings containing Fe-Si or Si particles were electrodeposited on 3.0%(mass fraction) Si steel sheets. The surface morphology, the cross-section and the silicon content of coating have been investigated, respectively. It was found that the number of particles on the coating surface and cross-section significantly decreased with increasing silicon content in the applied particles, leading to a decrease of the silicon content of coatings. About 10.2% silicon content of coatings deposited with Fe-30%Si particles can be obtained, whereas that for Si particles was only 2.9% at a particle concentration of 100 g/L and current density of 2 A/dm2. This is mainly attributed to the conductivity of applied particles. High conductivity can promote the co-deposition of the particles. With increasing silicon content in the particles, their conductivity decreased sharply, resulting in the decrease of silicon content of coatings. Present work may initiate a new method to modify the particle content of the composite coatings via changing the conductivity of the particles during the composite electrodeposition. In this paper, a possible mechanism was proposed to explain the phenomena. 相似文献
979.
P110钢CO2腐蚀产物膜的XPS分析 总被引:6,自引:0,他引:6
为了确定CO2腐蚀产物膜的组成及不同层次结构中成分和含量的差异,采用P110钢在高温高压腐蚀静态釜中制备CO2腐蚀产物膜,利用SEM观察了腐蚀产物膜的表面和断面形貌,结合XRD分析结果,通过XPS研究了两层结构膜的化学组成差异。结果表明,腐蚀产物膜断面呈现双层结构;膜层的主要成分是FeCO3,还有少量的CaCO3和铁的氧化物,但内层CaCO3较多且夹杂着Fe3C和单质Fe,外层氧化物稍多;通过内外层Ca^2+含量差异推断出内层腐蚀膜优先形成。 相似文献
980.
我们用混合物理化学气相沉积法(HPCVD)制备了一批不锈钢衬底的MgB2超导厚膜样品,厚度在10~30μm间,Tc(onset)是37.8~37.2K,超导转变宽度ΔT在1.2K左右,是(101)方向织构的致密厚膜,并有少许MgO杂相.对样品进行弯折研究,随着弯曲角度的增加,膜面出现不同程度的条状裂纹,但仍能保持膜面的基本完整;虽然样品的超导起始转变温度降低、转变温区变宽,性能有所下降,但超导特性仍能保持在一个很好的水平上.这个结果表明了采用HPCVD方法制备不锈钢衬底带材将会很好地克服MgB2超导膜由于硬脆的性质而无法绕制磁体的问题,有着十分重要的应用意义. 相似文献