A3钢在人造污染介质中的大气腐蚀行为

采用于湿交替复合循环模拟大气腐蚀过程，研究了Ａ３钢在含ＮａＣｌ、Ｎａ２ＳＯ４、ＮａＮＯ３、ＮａＣｌ＋Ｎａ２ＳＯ４和Ｎａ２ＳＯ４＋ＮａＮＯ３介质中的腐蚀行为．通过电化学测量，评价了Ａ３钢及其在加速腐蚀过程中形成的锈层的电化学行为和锈层的保护性，并利用ＸＲＤ分析了腐蚀产物的组成．试验结果表明，ＳＯ４２－腐蚀性最强，Ｃｌ－次之，ＮＯ３－最弱，且有一定的钝化作用；Ａ３钢在混合介质中的腐蚀行为不同于在单一介质中的腐蚀行为，每种介质在腐蚀的不同阶段分别起主要作用．     

N－105合金在NaNO_3和Na_2O_2沉积盐层中的高温氧化行为

用Ｘ－射线衍射、ＳＥＭ及ＥＤＡＸ方法研究了Ｎ－１０５合金在７００℃，ＮａＣＯ３和Ｎａ２Ｏ２沉积盐层中的高温氧化行为．结果表明，合金在ＮａＮＯ３沉积盐层中的腐蚀比Ｎａ２Ｏ２沉积盐层中更为严重．     

800合金的碱性应力腐蚀破裂Ⅱ.硫代硫酸盐的影响

采用Ｃ形环试验研究了在沸腾５０％ＮａＯＨ＋０．３％ＳｉＯ２溶液中添加Ｎａ２Ｓ２Ｏ３对８００全金ＳＣＣ行为的影响,半结合电化学测量等进行了讨论。Ｎａ２Ｓ２Ｏ３促进８００合金在高温碱性训的阳极溶解,使表面钝化膜稳定性下降,这主要归因于对Ｎｉ的阳极极化行为的影响,Ｎａ２Ｓ２Ｏ３使８００合金的碱性ＳＣＣ敏感电位范围扩大,开裂速率增加,其中在－４０ｍＶ（ＳＣＥ）左右最为敏感。     

NaNO2对A537钢在盐水中腐蚀疲劳的缓蚀作用

利用平板及单边裂纹试样研究了１％ＮａＮＯ２对Ａ５３７钢在３．５％ＮａＣｌ水溶液中腐蚀疲劳寿命与裂纹扩展的缓蚀作用，并在不同应变速率与外加电位下研究了相应体系圆柱形应变电极的电化学响应规律．结果表明，ＮａＮＯ２对裂纹萌生过程具有抑制作用，从而提高腐蚀疲劳寿命．即使在阴极极化条件下，动态应变的一定阶段仍可有较大的阳极溶解电流密度，这显示了ＮａＮＯ２对裂纹扩展过程作用的复杂性．分析表明，ＮａＮＯ２存在的情况下，形变引起的附加阳极电流密度除受到形变速率与新表面再钝化速率控制外，还强烈地受到表面滑移状态的影响．     

磁场和缓蚀剂对Fe／0.5mol.L^—1H2SO4等体系极化行为的影响

测定了Ｆｅ／Ｈ２ＳＯ４，Ｆｅ／Ｈ２ＳＯ４＋Ｎａ２ＳＯ４，Ｆｅ／ＨＳＯ４＋Ｆｅ２（ＳＯ４）３和Ｆｅ／Ｈ２ＳＯ４＋ＮａＣｌ种体系在磁场或／和缓蚀剂作用下的极化曲线，指出腐蚀的主要控制是阴极过程，Ｈ２ＳＯ４中加入少量Ｎａ２ＳＯ４不影响其结果，但加入Ｆｅ２（ＳＯ４）３，ＮａＣｌ会因Ｆｅ＾３＋，Ｃｌ＾－的作用而影响结果，分析了磁场、缓蚀剂、Ｃｌ＾－和Ｆｅ＾３＋单一和联合对Ｆｅ／Ｈ２ＳＯ４阴极和阳极极化行为的     

硅钨杂多化合物的复配缓蚀剂及其缓蚀机理研究

通过旋转挂片试验,对硅钨杂多化合物的复配缓蚀剂进行了缓蚀性能的研究。结果表明：Ｎａ８［ＳｉＷ１１Ｏ３９］－ＺｎＣｌ２复配缓蚀剂具有良好的缓蚀性能,Ｎａ８［ＳｉＷ１１Ｏ３９］－ＺｎＣｌ２－葡萄糖酸钠复配缓蚀剂具有优良的缓蚀性能。通过极化曲线和光电子能谱初步探讨了缓蚀剂的作用机理。它们是阳极型缓蚀剂,Ｚｎ＾２＋的主要作用是在金属表面快速成膜,硅钨杂多化合物的作用不仅在金属表面,而且在次表面也起成膜作用     

应变幅与应变速率在形变加速腐蚀过程中的作用

采用应变电极技术研究了应变幅、应变速率与外加电位对形变中金属电化学腐蚀过程的影响。选用的体系为工业纯Ｆｅ－３．５％ＮａＣｌ水溶液和Ａ５３７钢－３．５％ＮａＣｌ＋１％ＮａＮＯ２水溶液结果表明，塑性变形对阳极过程的加速作用大于对阴极过程的加速作用，这种作用主要发生在自腐蚀电位附近。在强阳极与强阴极极化区，由于强的分反应驱动力，单个反应的电流增大，导致了形变电流的增加相对不重要。活化体系的金属溶解电流主要受应变幅控制，而钝化体系则主要由应变速率控制，取决于应变活化区域的再钝化动力学过程．     

电镀锌钢板涂敷型低铬钝化研究

应用正交试验优选电镀钢板－ＣｒＯ３－Ｈ３ＰＯ４－ＳｉＯ２系钝化剂配方,研究钝化注ｐＨ值,钝化时间,干燥温度对钝化膜耐蚀性的影响,提出一种涂敷型低铬钝化新工艺。该工艺所得钝化膜稳定性好,其抗白锈能力是目前国产涂敷型铬酸盐处理镀锌钢板的３倍。文中还对ＣｒＯ３－Ｈ３ＰＯ４－ＳｉＯ２系钝化膜的形成机理和防护机制进行了初步探讨。     

800合金的碱性应力腐蚀破裂Ⅰ.外加电位的影响

采用恒电位Ｃ环形ＳＣＣ试验方法，研究８００合金在含０．３％ＳｉＯ２和０．３％Ｎａａ２Ｓ２Ｏ３的沸腾５０％ＮａＯＨ溶液不的ＳＣＣ行为，并结合极化曲线测试及表面膜俄歇电子能谱（ＡＥＳ）分析结构进行了讨论。结果表明，在约－０．３０Ｖ（ＳＣＥ）以上的较高电位钝化区，８００合金对碱性ＳＣＣ非常敏感，而在约－０．４５Ｖ（ＳＣＥ）以下电位，ＳＣＣ敏感性大大降低。这与较高电位下生成严重贫铬的Ｎｉ和Ｆｅ的氧化膜。而     

改性咪唑啉缓蚀剂在H2S-3%NaCl-H2O体系中缓蚀性能的研究

以环烷酸和二乙烯三胺为原料,合成了咪唑啉,分别经过了乙氧基化反应和季铵化反应对其改性得到ＨＭ、ＨＭＯ,并在Ｈ２Ｓ－３％ＮａＣｌ－Ｈ２Ｏ体系中通过腐蚀实验及极化曲线测量,对其缓蚀性能进行了评价,实验结果表明,ＨＭ、ＨＭＯ对抑制Ｈ２Ｓ－３％ＮａＣｌ－Ｈ２Ｏ体系中碳钢的腐蚀有良好的效果,二者均有以控制阳极反应为主的混合型缓蚀剂。     

Adsorption of a bromine labeled carboxylic acid corrosion inhibitor on iron measured with EQCM, EIS and XPS

Adsorption of bromine labeled aromatic carboxylic acid corrosion inhibitor on iron, polarized in the active region, was studied with the rotating electrochemical quartz crystal microbalance (rEQCM), electrochemical impedance spectroscopy (EIS) and X-ray induced photoelectron spectroscopy (XPS). The EQCM quantifies adsorption via the mass loss resulting from the fact that the inhibitor replaces water molecules in the interfacial volume occupied by the adsorbent. EIS permits to characterize adsorption by determining changes in the double layer capacity resulting from addition of the inhibitor to the solution. Finally, XPS provides an independent ex situ analysis of the electrode surface after completion of an adsorption experiment. Results obtained with EQCM and EIS by adding increasing amounts of the model inhibitor to 0.1 M NaClO₄ suggested that monolayer coverage was reached at the surface at a concentration of 2.25×10⁻² M. XPS data indicate that the surface concentration approaches a limit in this concentration range. The EQCM adsorption data fitted best the Langmuir-Freundlich isotherm. Compared to a previously studied similar inhibitor without Br substituent, the present inhibitor replaced more water from the surface layer and it exhibited a higher adsorption constant. Consistent with these observations, linear sweep experiments showed it to be more effective in suppressing the anodic dissolution in the active region. The different results of this study confirm the usefulness of the EQCM for the characterization of competitive adsorption of corrosion inhibitors involving replacement of the solvent from the electrode surface.     

Electrochemical behaviour of an inhibitor film formed on copper surface

The potential dependence of adsorption and kinetic properties of inhibitor film formation on copper surface was studied in acidic environment by using surface sensitive techniques: electrochemical quartz crystal microbalance (EQCM) and electrochemical scanning tunneling microscopy (EC-STM). The investigated inhibitor was 5-mercapto-1-phenyl-tetrazole (5-MPhTT) in 1 mmol dm⁻³ H₂SO₄ solution. The QCM investigations were done to study the electrode mass changes in absence and presence of 5-MPhTT at rest potential. The apparent mass and current variation as a function of the electrode potential was registered in order to study the protective film and its breakdown. Results revealed that the anodic current density and the electrode mass loss is twice less in presence of 5-MPhTT. We also present results of an in situ STM study on the surface morphology and anodic dissolution of Cu(1 1 1) electrodes in inhibited/uninhibited electrolytes. The images gave information about the nature of the protective layer. The results were analyzed and discussed.     

Anodic oxide growth on tungsten studied by EQCM, EIS and AES

Anodic oxide growth on tungsten in 0.1 M H₂SO₄ + 0.4 M Na₂SO₄ has been studied on stationary and rotating electrodes using the electrochemical quartz crystal microbalance (EQCM), Auger electron spectroscopy (AES) depth profiling, electrochemical impedance spectroscopy (EIS) and the rotating ring disc electrode (RRDE). The sputter rate of tungsten oxide was calibrated with respect to a tantalum oxide reference film using Rutherford backscattering spectroscopy (RBS). Long time polarisation experiments at constant potential showed that at a stationary electrode the oxide thickness determined by AES increased with time, whereas a steady state was reached after a few seconds under rotating conditions. On the other hand, EIS indicated a time independent oxide thickness on both stationary and rotating electrodes. Both methods yielded a higher absolute thickness for stationary electrodes. The oxide growth behaviour at short times was studied with the EQCM by monitoring the current and the mass change resulting from a potential step. From these data the film growth fraction and the oxide thickness change were calculated. After an initial period of a few seconds dominated by film growth, the rotating electrodes exhibited a significant mass loss contrary to stationary electrodes. RRDE experiments confirmed dissolution during anodic polarisation of a rotating electrode. The results of this study demonstrate the necessity to combine several experimental methods when studying anodic film growth and they illustrate the usefulness of the EQCM which can monitor directly and with sub-second time resolution the mass change of the electrode together with the current density. They show the decisive effect of convection conditions on anodic oxide growth on tungsten.     

Cu电极上咪唑与苯并三唑共吸附的SERS研究

用表面增强拉曼散射(SERS)技术研究了缓蚀剂咪唑(IM)与苯并三唑(BTAH)在铜电极上的共吸附行为.实验表明,IM与BTAH能共吸附于Cu电极表面,IM的存在有利于BTAH的吸附,二者有良好的协同效应.     

Application of Electrochemical Quartz Crystal Microbalance Technique to Hydrogen/Lithium Insertion into MnO2/LiCoO2 Electrode in Aqueous/Non-aqueous Solution

The hydrogen insertion/desertion into/from MnO₂ electrode in aqueous solution and the lithium intercalation/ deintercalation into/from LiCoO₂ electrode in non-aqueous solution have been investigated by usingin-situ electrochemical quartz crystal microbalance (EQCM) technique combined with cyclic voltammetry (CV) and galvanostatic charge-discharge experiment. In the case of the MnO₂ electrode, the combined cyclic electrogravimetric and CV results indicated that the redox potentials at the transition in oxidation state of manganese ion measured on the cathodic scan are satisfactorily in accord in value with those thermodynamic e-quilibrium potentials calculated in Pourbaix diagram. The positive/negative slope with a constant value in the plot of mass change rate vs. potential means that the reaction is inclined to proceed in the direction of an oxidation/reduction between two phases. From the electrogravimetric curves obtained simultaneously with galvanostatic discharge curves, the discrepancy between the charge and mass variations was discussed in relation with the hydrogen-induced stress. In the case of the LiCoO₂ electrode, the cyclic electrogravimetric data obtained simultaneously with CV indicated that neither solvent nor any of other species but lithium ions are intercalated into and deintercalated from the electrode. From the cyclic electrogravimetric curve obtained simultaneously with galvanostatic charge-discharge curve, the discrepancy between the charge and mass variations was discussed in relation with the change of the molar volume and surface roughness of the electrode during the lithium intercalation and deintercalation.     

Anodic dissolution of gold in alkaline solutions containing thiourea, thiosulfate and sulfite ions

Gld dissolves electrochemically in alkaline solutions containing ligands to form complex ions with gold ion.Therefore,selective leaching of noble metals is expected without dissolution of base metals such as steels,aluminum alloys in scrap treatment.Gold electrodes were investigated using linear sweep voltammetry,EQCM method and potentiostatic eclectrolysis in alkaline solutions containing thiourea,Na2SO3 and Na2S2O3.The solution composition,electrode potential affect gold dissolution rate and current efficiency.The gold dissolved from anode electrode forms complex ions,suspension particles as compound precipitates and deposits on cathode electrode as a metal.Anodic efficiency for gold dissolution is between 10% and 22%.This is caused by the oxidation decomposition of sulfite ions and thiourea.The statbility of the alkaline solution containing these elements was also estimated by capillary electrophoresis technique.     

天然气井中成膜型碳钢缓蚀剂的评价

成膜型缓蚀剂以间歇投药方式广泛应用于天然气井ＣＯ２腐蚀控制。本工作在ＣＯ２饱和水溶液中用电化学阻抗技术对碳钢缓蚀剂的行为及膜寿命进行了评价,定义了一个系数Ｆ（ｔ）为膜寿命的指标,并就环境、金属表面及分步成膜时间对缓蚀性能的影响进行了评价,三研究结果为缓蚀剂在气田井管ＣＯ２腐蚀控制中的应用提供了可行的解决方法,     

Investigating metal‐inhibitor interaction with EQCM and SVET: 3‐amino‐1,2,4‐triazole on Au,Cu and Au–Cu galvanic coupling

This study reports a multiscale electrochemical investigation of the interaction between the organic compound 3‐amino‐1,2,4‐triazole (ATA), regarded as corrosion inhibitor, and two noble metals (Cu and Au), either separated or under galvanical coupling. Open circuit potential measurements show that Cu is not protected by the application of ATA, having its potential shifted towards more negative values, while on Au exhibits a slight inhibitive effect. The adsorption free energies were determined using the electrochemical quartz crystal microbalance (EQCM), with values that correspond to physisorption on either metal. The surface reactivity of the inhibitor‐modified metals in chloride‐containing aqueous solution was studied using the scanning vibrating electrode technique (SVET), showing high spontaneous activity, associated to electron transfer reactions in systems containing Cu and 3‐amino‐1,2,4‐triazole.     

Pt和Sb、S吸附原子修饰的Pt电极上1,3-丁二醇吸附和氧化过程

应用电化学循环伏安和石英晶体微天平（EQCM）研究了1，3－丁二醇（1，3－BDL）在Pt电极和以Sb,S吸附原子修饰的Pt(Pt/Sbad和Pt/Sad)电极上的吸附和氧化过程，从电极表面质量变化的结果分析，可认为1，3－丁二醇的氧化与电极表面氧物种有着极其密切的关系。Pt电极表面Sb吸附原子能在较低的电位下吸附氧，可显著提高1，3－丁二醇电催化氧化活性，与Pt电极相比较，饱和吸附Sb原子的Pt电极，1，3－丁二醇氧化的峰电位负移了0．25V，峰电流增加了近1倍，相反，Pt电极表面S吸附原子的氧化会消耗表面氧物种，饱和吸附S原子的Pt电极上1，3－丁二醇的电氧化受到抑制，本文从表面质量变化提供了吸附原子电催化作用的新数据。     

Electrochemical oxidation of pyrrhotute in aqueous solution

The anodic surface oxidation of natural pyrrhotite in 0.3 mol/L KCI and HCI solution （pH 4.0） and 0.1 mol/L Na2B4O7 solution （pH 9.18） respectively was investigated by using cyclic voltammetry, Tafel plot, and chronoamperometry. In 0.3 mol/L KCl and HCl solution （pH 4.0）, at potential less than 0.5 V（vs SHE）, the production of anodic oxidation on pyrrhotite surface can not maintain a stable phase to form a passive film. In 0.1 mol/L Na2B4O7 solution （pH 9.18）, when the electrode potential increases to more than 0.5 V （vs SHE）, part of S is oxidized to sulfate, making the passive film somewhat porous, but elemental S and metal oxidates Fe（OH）3 still remain on the electrode surface, and the passive film can not be broken down totally. According to PARCalc Tafel analysis, the corresponding corrosion current density （J0） is 5.34 μA/cm^2 , which is also the exchange current density of the oxidation reaction on pyrrhotite electrode surface in 0. 1 mol/L Na2B4O7 solution （pH 9. 18）. The electrochemical dynamics equation of the oxidation was determined.