金属腐蚀与防护简谈

本文简要阐明了为什么金属的腐蚀主要以电化学腐蚀的形式出现,剖析了腐蚀过程电化学动力学参数的物理意义,以及金属腐蚀的防护原理、常用的腐蚀防护方法乃至腐蚀过程的一些特殊应用。     

椭圆偏振光谱技术的腐蚀研究应用

椭圆偏振光谱技术是一种高度灵敏、非破坏性的原位实时表征技术,可获取腐蚀过程“电极材料-介质”界面的动态变化信息,因此在腐蚀研究中得到了广泛应用. 本文结合解析椭圆偏振光谱数据所采用的光学模型的发展,介绍了近年来椭圆偏振光谱技术在腐蚀研究中的典型应用,并分析了该技术的发展趋势.     

金属线电极分形生长的模拟

电沉积金属过程中,阴极沉积的金属边缘会出现包括枝晶生长在内的许多复杂形态,这会严重影响电沉积产品的质量和加工过程中的电流效率. 对枝晶分形生长的过程以及形貌进行研究,可以实现对沉淀物的可控生长. 本研究使用Python和Matlab软件相互结合,基于扩散限制凝聚（DLA）模型,建立平行线电极电沉积的模型. 通过分析不同粒子数、沉积概率、电极间距、运动步长、定向漂移条件下的分形生长的变化规律,以及模拟参数与实际电沉积因素对分形生长影响的内在联系,发现只要合理控制模拟的粒子数、沉积概率、线电极间距、运动步长、定向漂移概率参数即可与实际电化学体系的浓度和沉积时间、还原概率、两极间距、温度和电压、电极的相对位置和形状一一对应,从而模拟得到跟实际电沉积接近的分形图,最终可实现对分形生长的可控操作,对分形生长在工业电沉积等方面应用有很大的意义.     

芳烷基酚树脂在98%硫酸中腐蚀行为研究

用失重和表面腐蚀层厚度的测定以及借助于Ｘ光电子能谱（ＸＰＳ）、红外吸收光谱（ＦＴ—ＩＲ）、扫描电子显微镜（ＳＥＭ）等分析手段研究芳烷基酚树脂在浓硫酸中的腐蚀行为。探讨耐浓硫酸腐蚀机理模型。结果表明试样经一定时间浸泡后表面腐蚀层厚度对温度和作用时间没有依赖关系，该材料耐浓硫酸腐蚀。腐蚀机理为：浸泡过程中，试样表面形成了一层结构致密的耐腐蚀物质，阻止了硫酸分子进一步向试样内部扩散渗透，使试样内部免遭进一步破坏。     

用于预测高温高浓度溴化锂溶液中碳钢腐蚀行为的BP神经网络(英文)

本文建立了预测碳钢在LiBr溶液中腐蚀速率的神经网络模型.该模型拟合了碱度,温度,LiBr和Na2MoO4浓度变化对碳钢全面腐蚀速率的影响,可用于准确预测不同温度下,在含有不同缓蚀剂的LiBr溶液中的碳钢腐蚀速率,其预测值和实验值完全吻合,为研究溴冷机中金属材料的腐蚀和现场监测提供了新的思路和方法.     

微电极法研究不锈钢点腐蚀发生发展过程

应用微电极法研究不锈钢点腐蚀发生发展过程，首镒获得了不锈钢夹杂物缺陷在阳极活化电位的活性溶解信息和点腐蚀发展过程蚀点生长和消止两个相互竞争，不断发展的动态行为，深化对夹杂物缺陷诱点腐蚀的发生及点腐蚀发展过程机理的认识。     

金属在土壤中的腐蚀

由于土壤的组成及结构的复杂性,其腐蚀远比大气腐蚀复杂得多。本文就金属在土壤中的腐蚀作些探讨,特别较详尽地分析土壤中微生物对金属腐蚀的特点及类型。研究表明,参与金属腐蚀过程的细菌,并非本身使金属腐蚀,而是细菌生命活动的结果间接地对金属电化学腐蚀过程产生的影响。随着现代化城乡建设,地下设施日益增多,当今,研究土壤的腐蚀规律及其控制显得格外有意义。     

青铜器文物腐蚀受损原因的研究

以三千多年前商周时代为代表的青铜器是我国金属质地文物中的珍品。本文调查了青铜病的发现‘症状’,对青铜病形成的过程和原因,以小孔腐蚀原理研究了溶液的ＰＨ值和Ｃｌ＾－浓度对青铜腐蚀的影响,进行了模拟闭塞电池内化学和电 化学状态的研究,提出出青铜病的产生机理并探讨符合文物保护要求的青铜器保护处理方法。     

Corosion Potential Imagingat the InterfaceofCoating／MetalbyaNewElectrochemicalTechnique

在绝大多数环境下，聚合物／金属界面的腐蚀破坏的本质是电化学过程，因此，不少电化学技术，包括直流稳态技术和交流阻抗技术等被广泛用于研究金属／聚合物界面的腐蚀破坏机制，评测有机涂层的耐蚀性能．然而，由于聚合物／金属界面腐蚀破坏的“闭塞”条件和聚合物膜层的高绝缘性，传统的电化学方法均不能直接获得聚合物／金属界面二维空间的腐蚀电位分布，难以直接研究聚合物／金属界面的腐蚀破坏过程及相关的影响因素．聚合物／金属界面腐蚀电位的测量有助于研究聚合物／金属等复合材料界面腐蚀破坏机理，评测有机聚合物涂覆层的耐蚀性能．本文提出一种微计算机控制的阵列电极技术，用于原位测量金属／聚合物界面电位分布．首次建立了８×８阵列电极和微机控制的阵列电极测量系统，可直接测量聚合物／金属界面腐蚀电位的二维分布．由此可深入研究有关腐蚀物种在聚合物相内传输过程，聚合物涂层的不均一性及缺陷分布，以及聚合物／金属界面腐蚀的发生、发展机制．应用阵列电极技术首次在原位获得聚合物涂层的缺陷分布及不均一性，并考查了聚合物涂层缺陷对诱导聚合物／金属界面腐蚀破坏的关系．阵列电极技术还首次提供了在聚合物／金属界面腐蚀破坏发展过程中阴、阳极同时存在，共同发展的直接的     

数码技术在金属电化学腐蚀教学中的应用*

数码显微、延时摄影等数码技术可以应用于铁的吸氧腐蚀实验,帮助学生观察细节现象及变化过程。在“探究海洋工程中钢管桩腐蚀速率曲线的奥秘”的教学中,数码技术支持下的吸氧腐蚀实验,能促进学生构建供氧均匀和供氧不均匀2种吸氧腐蚀认知模型,达成教学目标。     

碳钢土壤腐蚀速度波动性表征的研究

碳钢/土壤腐蚀是复杂的随机现象。按照统计学方法，其腐蚀速度被看作服从正态分布，腐蚀速度的波动性分别用标准偏差或变异系数(CoV)表示。笔者根据大量腐蚀试验数据，将标准偏差分布看作统计分形体系，分别计算了平行腐蚀试验数据和区域腐蚀试验数据的分维，分别为1．343和1．486。通过分形修正提出新的变异系数来描述碳钢土壤腐蚀的随机波动性。此外，当平行试样数量大于6片后分维趋于恒定。新变异系数和腐蚀发生程度无关，是腐蚀速度随机波动特性更好的表征形式。     

Sub-micrometre imaging of metal surface corrosion by scanning Kelvin nanoprobe

The detection of the initial changes in the surface microstructure and local chemical properties connected to the corrosion process is possible using a high-resolution scanning Kelvin nanoprobe. This technique provides the simultaneous imaging of the topographical features and potential distribution across a surface at the sub-micrometer level. Nanoprobe measurements performed on samples of Al, Cu, Fe, Ni, Ag and Pt before and after exposure to different corroding solutions reveal the significant changes that take place during the first stages of the corrosion process. The similarities of the images obtained subsequent to corrosion are reflective of surface fractal behavior.     

Pitting Corrosion Mechanisms and Characteristics of Aluminum in Solar Heating Systems

The complex characteristics and mechanisms of aluminum pitting corrosion in a solar heating system were studied by the chemical immersion method and electrochemical techniques as well as fractal theory. The results showed that pitting corrosion of Al occurred in a tap water environment due to the local enrichment of Cl^? ions. The higher the Cl^? ions concentration, the more negative the critical pitting potential (E_b) of Al. A linear relationship between E_b and the logarithm of Cl^? ions concentration was observed. The pitting corrosion mechanism of Al in neutral water was explained in terms of complexation corrosion theory. The corrosion surface images of aluminum immersed in tap water were captured and analyzed by image processing technique and box‐dimension method. The fractal characteristics of pit distribution, described by fractal dimension, have been identified. The fractal dimension of the pit distribution increased with the increase of immersion time and had the same trend as that of the weight loss. Fractal dimension can, thus, be used as an important parameter for quantitative evaluation of pitting corrosion of aluminum.     

Menger sponge-like fractal body created by a novel template method

We have established experimental strategies on how to create a Menger sponge-like fractal body and how to control its fractal dimension. The essence was to utilize alkylketene dimer (AKD), which spontaneously forms super-water-repellent fractal surface. We prepared "fractal AKD particles" with fractal surface structure as templates of pores in fractal body. The fractal body was synthesized by filling the remained space between the packed template particles with a tetramethyl orthosilicate solution, solidifying it by the sol-gel process, and removing the template by calcinations. We have succeeded in systematically creating fractal bodies of silica with different cross-sectional fractal dimensions D(cs)=1.87, 1.84, and 1.80 using "fractal template particles" compressed under the ratio=1.0, 2.0, and 3.0, respectively. We also discussed the possibilities of their fractal geometries in comparison with mathematical models. We concluded that the created fractal bodies were close to a Menger sponge and its modified one. Our experimental strategy allows us to design fractality of porous materials.     

阳极氧化AZ91D镁合金在氯化钠稀溶液中的腐蚀行为

利用盐雾实验、极化曲线扫描、电化学阻抗谱和电化学噪声技术等电化学研究方法结合扫描电镜表面观测技术对AZ91D镁合金氧化膜在1%(w)氯化钠溶液中的耐蚀性能进行了评价. 结果表明, 氧化前后的镁合金腐蚀行为发生明显改变, 如未封孔的阳极氧化膜耐中性5%氯化钠盐雾试验时间超过200 h; 氧化后的镁合金自腐蚀电位明显正移, 点蚀诱导期延长; 阳极氧化膜的高频阻抗约为裸露镁合金的数千倍, 这些变化证明阳极氧化处理使镁合金获取了十分优异的耐蚀性能. 首次利用分形维数Df的变化规律初步描述氧化后AZ91D镁合金的腐蚀过程. 可以发现随着浸泡时间的延长, Df呈现出初期快速增长, 随后出现波动, 最后稍有降低的变化过程. 这种现象对应于氧化后AZ91D 镁合金在1%氯化钠溶液中腐蚀的三个阶段.     

Copper patina corrosion evaluation by means of fractal geometry using electrochemical noise (EN) and image analysis

Chaos theory and the use of fractal geometry originated a new methodology to study EN signals obtaining new information on corrosion processes. A clear direct relationship is obtained between fractal analysis of EN time series and images.     

Investigation on corrosion inhibition effect of N-[4-(1,3-benzo[d]thiazol-2-ylcarbamoyl)phenyl]quinoline-6-carboxamide as a novel organic inhibitor on mild steel in 1N HCl at different temperatures: Experimental and theoretical study

A new novel organic corrosion inhibitor N-[4-(1,3-benzo[d]thiazol-2-ylcarbamoyl)phenyl]quinoline-6-carboxamide (NBCPQC) has been synthesized. The synthesized novel organic inhibitor NBCPQC used to be carried out on mild steel corrosion in 1N HCl for the first time. The studied inhibitor was once evaluated as corrosion inhibitor for mild steel in 1N of HCl solution using electrochemical research which advocated that a protective film is form by the process of inhibitor absorption on the surface of mild steel. Inhibitor shows a better inhibiton efficiency of maximum above 90% in 1N HCl medium. Inhibitors show a better efficiency by way of reducing and sluggish down the corrosion process however on growing the temperature it is weakened on controlling corrosion. In addition to this adsorption isothermal models had been interpreted to fit the adsorption behaviour of the inhibitor compound on mild steel surface. Thus the result reveals that the compound shows a Langmuir adsorption isotherm.