Considerations on reproducibility of potential and corrosion rate measurements in reinforced concrete

This communication analyses information supplied by the electrochemical parameters related to rebar corrosion in reinforced concrete structures (RCS). Corrosion potential and corrosion current density are determined for different sets of conditions. Tests are performed to gather data on conflictive aspects of the two electrochemical parameters, with regard to evaluating the results of RCS inspections. Consideration is made of the limitations of potential measurements if not accompanied by complementary indications such as concrete resistivity, rebar surface area involved in the measurements, or the instrumentally determined corrosion current. The capacity of galvanostatic pulses applied directly on large RCS to offer a reliable guide to corrosion rate of steel reinforcements is discussed.     

Eurocorr 2017 in combination with the 20th international corrosion congress and the process safety congress 2017: corrosion control for safer living – Part 1

The 2017 EUROCORR congress was held in the Congress Centre, Prague, Czech Republic, from 3rd to 7th September 2017. For the first time, this flagship event of the European Federation of Corrosion was combined with two other prestigious events: the 20th International Corrosion Congress and the Process Safety Congress 2017. Hence the theme of the congress was Corrosion Control for Safer Living. A review of this major corrosion event will be provided over four issues, in four parts, with the opening and plenary lectures and technical sessions on atmospheric corrosion, automotive corrosion, corrosion in aerospace, corrosion of steel in concrete and various coatings-related topics being covered in the present instalment.     

Corrosion performance of friction surfaced nickel aluminium bronze (NAB) alloy under erosion corrosion and salt fog environment

ABSTRACT

In the present research work, the extruded nickel aluminium bronze (NAB) alloy is friction surfaced over cast NAB alloy as a repairing technique for the deteriorated marine components. The friction surfaced specimens were tested for their corrosion properties. The corrosion tests such as salt fog test, erosion–corrosion test and pitting corrosion test were conducted to investigate the corrosion behaviour of the friction surfaced NAB alloy. It is found that the accumulation of corrosion occurred due to the presence of a continuous network of the ΚIII-phase. The lower corrosion rate is achieved in friction surfaced NAB alloy compared to the base NAB alloy which is contributed by the corrosion resistant contents such as Al and Cu and also by the fine grain microstructure obtained during the friction surfacing process.

This paper is part of a supplementary issue from the 17th Asia-Pacific Corrosion Control Conference (APCCC-17).     

石化企业腐蚀控制中科学管理的思维(纪念《全面腐蚀控制》创刊20周年)

石油化工设备应从设计、制造、操作运行、储运安装与维修等方面进行全面腐蚀控制,全面腐蚀控制应以科学管理作保证。本文论述了设备防腐蚀管理的主旨与要素,并用具体实例说明在腐蚀控制中实践探索与解决矛盾的思路,讨论了腐蚀控制中经济分析的两重性。     

铸铁在海水中的腐蚀行为

报告了18种铸铁在天然海水和流动海水中的腐蚀试验结果,总结了它们在海水中的腐蚀行为,普通铸铁在天然海水及流动海水中的腐蚀速度与碳钢接近,低合金铸铁在海水中的腐蚀行为与普通铸铁相似。CrSbCu铸铁在海水中的腐蚀比普通铸铁轻,添加Ni,Ni-Cr,Ni-Cr-Mo,Ni－Cr-Cu,Ni-Cr-Re,Cu-Sn-Re,Cu-Cr,Cu-Al等的低合金铸铁在海水中的腐蚀速度与普通铸铁无明显差别,加入少量Ni,Cr,Mo,Cu,Sn,Sb,Re等合金元素可减小铸铁在海洋大气区的腐蚀速度,高镍铸铁在天然海水及流动海水中的腐蚀均较轻。     

金属在海水中的腐蚀电位研究

获得了３８种金属在天然海水中浸泡１８０ｄ的腐蚀电位数据，列出了它们在海水中的腐蚀电位序，讨论了金属材料在海水中的腐蚀电位特性，分析了它们在海水中的腐蚀电位与耐蚀性的关系。结果表明，钝化能力强的金属，其腐蚀电位随浸泡时间变化较大，电位稳定时间较长，非钝化金属和钝化能力弱的金属则相反，对铝合金来说，初始电位，稳定电位较负，其耐蚀性较好，反之则较差。对不锈钢来说，稳定电位较正，其耐蚀性较好，反之则较差。     

环保型镀锌层蓝色钝化膜耐腐蚀性能的研究

采用钛盐溶液替代铬酸盐溶液对镀锌层进行表面钝化处理,获得了色泽光亮、耐腐蚀性能优良的蓝色钝化膜层。探讨了钛盐钝化溶液成分及工艺参数对镀锌层表面钝化膜的耐腐蚀性影响;中性盐雾、电化学测试等腐蚀性能试验结果表明,钛盐钝化溶液所获得的蓝色钝化膜,其耐腐蚀性能更优于铬酸盐钝化膜。     

缓蚀剂缓蚀作用的研究方法

缓蚀剂防护技术在石油、化工、冶金等领域得到了广泛的应用。腐蚀研究方法对于指导缓蚀剂的合成、优化及应用具有十分重要的间谍。对电化学、光谱学等腐蚀研究的传统方法和近代分析测试技术进行综述,并简要介绍了其现状与应用情况。     

影响热水锅炉腐蚀的主要因素及水质判定指标

用极化曲线法研究了影响热水锅炉水质腐蚀性的主要因素。根据《均匀腐蚀的十极标准》验证了大连港务局房产公司四工区热水锅炉的补给水和循环水对钢的腐蚀速度均小于０．５ｍｍ／ａ，中属于可用级的，同时也提出了热水锅炉水质腐蚀吕质腐蚀的判定指标，具有一定的实际意义。     

Electrochemical measurement to examine influence of ions,DO, and pH on corrosion of early-generation conduits

ABSTRACT

In order to effectively implement measures against the adverse effects of large earthquakes on telecommunication conduits, it is important to elucidate which conduit is vulnerable. Telecommunication conduits consist of pipe bodies and joints, and as is well known the joints are weaker than the bodies against seismic loading. Hence, the seismic performance of the conduits depends on the performance of the joints. To maintain conduits properly, the corrosion rate of conduits' joint in the field must be determined. Several sites were selected and investigated for the amount of stagnant water in manholes. Next, the stagnant water test specimens were collected and observed for the extent of corrosion inside via a pipe camera, and subsequently analysed collected water test specimens. Moreover, the solution resistances and polarisation resistances using the AC impedance method and carbon steel coupons were measured. The experiments revealed differences between the measured values recorded at the different sites. It was also found that some data were related to corrosion on the inside of the conduits.

This paper is part of a supplementary issue from the 17th Asia-Pacific Corrosion Control Conference (APCCC-17).     

非晶态Ni-Mo-P合金耐蚀性研究

从理论上分析了金属腐蚀的原因及实质,论述了不同合金层具有不同的化学性质,指出非晶合金具有特殊的化学性质,这与它的结构有关。并且试验研究了具有这种特殊非晶结构的Ni-Mo-P合金层的耐蚀性。在大量实验的基础上,确定了获取三元合金镀层的工艺配方,即15～25g/L硫酸镍,15～20g/L次亚磷酸钠,3～5g/L钼酸钠,另外含少量的络合剂和稳定剂。经结构分析所得合金层为非晶态结构。腐蚀实验证明该镀层具有很好的耐有机溶剂及有机酸和盐的性质;有耐强碱和耐浓硫酸的特性。     

现代化城市建设与腐蚀防护

为了创造舒适优美的生活空间,人们正在加快现代化城市建设。为此,需要解决一系列的技术问题,其中之一就是要解决城市现代化设施,例如,电视发射塔、微波发现塔、高级宾馆、居民公寓以及通往各户的水、电、暖气、煤气的运输管线等在建设中和使用中的腐蚀问题。通过各种防护技术,进行腐蚀控制、防止这些设施发生故障、引起事故,尽可能延长其使用寿命,以达到高效使用、安全运行、长期为人类服务的目的。本文站在腐蚀科学和表面工     

Corrosion behaviour of magnesium in ethylene glycol

Corrosion of magnesium engine components by coolant is an important issue in the automotive industry where magnesium alloys may be used. It is of significance to understand the corrosion behaviour of pure magnesium in ethylene glycol solutions, as this can provide a basis for developing new coolants for magnesium alloy engine blocks. In this paper, through corrosion and electrochemical tests, it was found that the corrosion rate of magnesium decreased with increasing concentration of ethylene glycol. Individual contaminants, such as NaCl, NaHCO₃, Na₂SO₄ and NaCl can make aqueous ethylene glycol solution more corrosive to magnesium. However, in NaCl contaminated ethylene glycol, NaHCO₃ and Na₂SO₄ showed some inhibition effect. The solution resistivity played an important role in the corrosion of magnesium in ethylene glycol solutions, and the competitive adsorption of ethylene glycol and the contaminants on the magnesium surface was also responsible for the observed corrosion behaviours. The corrosion of magnesium in ethylene glycol can be effectively inhibited by addition of fluorides that react with magnesium and form a protective film on the surface.     

带锈铸铁在3.5%NaCl溶液中的腐蚀行为研究

采用增重法和强极化、线性极化技术,研究了已生成较厚砂锈层的带锈铸铁在３．５％ＮａＣｌ溶液中的腐蚀与电化学行为,分析较厚砂锈层对铸铁腐蚀的影响,结果表明,带锈铸铁的腐蚀速度比裸铸铁的腐蚀速度大,较厚砂锈层不仅不能阻碍腐蚀过程继续发展,而且还有加速腐蚀发展的趋势。带锈铸铁的间浸腐蚀速度比全浸快得多,较厚砂锈层使间浸对带锈铸铁的腐蚀加速作用比对裸铸铁的加速作用更大。     

高温含杂质醋酸中00Cr20Ni25M04.5Cu不锈钢腐蚀分析

通过不同浓度甲酸－醋酸混合溶液中添加不同含量的氯离子,对00Cr20Ni25Mo4.5Cu不锈钢进行浸泡试验,分析了醋酸回收塔中段00Cr20Ni25Mo4.5Cu不锈钢的腐蚀原因以及控制腐蚀的条件。     

硫磺回收装置中冷凝却器的腐蚀和防护

详细分析了硫磺回收装置中冷凝冷却器的腐蚀原因,在生产实践基础上提出了相应的防护策略。     

中国工业与自然环境腐蚀调查的进展

简要介绍了中国工程院咨询项目《中国工业和自然环境腐蚀问题调查与对策》的进展,包括能源、交通、建筑、机械、化工、基础设施、水利和军事设施等典型的行业和企业的腐蚀损失。用Uhlig方法和Hoar方法所得到的年腐蚀损失结果相近,分别为．2008亿元和2288亿元人民币。如果包括间接损失,借鉴国外利用国民经济投入一产出表的计算结果进行对比,我国每年腐蚀总损失可达5000亿元以上,约占国民生产总值(GNP)的5％。应如同对待医学和环保一样重视腐蚀问题。提出了从国家的层面上加强腐蚀管理,进一步制定防腐蚀的国家规划和立法,完善防腐蚀的标准和规范体系以及加强基础研究和腐蚀工程教育的建议。     

储罐底板腐蚀的预测研究

影响储罐底板腐蚀的因素很多，它的腐蚀深度和腐蚀速度是随时间变化的灰色量。为了预测储罐底板的腐蚀状况，掌握储罐底板腐蚀的基本规律，应用灰色理论中的GM(1，1)模型对储罐底板腐蚀速度的实际统计数据进行了灰色动态拟合，建立了相应的预测方程，对储罐底板的腐蚀深度和腐蚀速度进行了预测，并建立了残差值的GM(1，1)模型对原预测值进行补偿，从而提高了预测精度和平稳度，为储罐腐蚀防护提供了科学的依据。     

Eurocorr 2016: linking science and engineering – part 4

The 2016 Eurocorr Meeting was held in Montpellier, France, from 12 to 15 September 2016. The focus of the meeting was Linking Science and Engineering. The meeting attracted over 1000 delegates from at least 53 countries with France, Germany, the UK and Japan providing around half the delegates between them. Over 400 oral presentations, more than 200 of which were full papers, and over 140 posters were presented during the sessions and workshops. Parts 1–4 of this report present a review of the technical sessions over four issues with sessions on Advanced Analytical Methods for Corrosion Research, CO₂-Corrosion in Industrial Capture Transportation and Utilisation Applications, Cathodic Protection of Steel in Concrete, Coatings for High Temperature, Corrosion Education, Improving Corrosion Control of Ships, Marine Corrosion, Corrosion Issues for Renewable Energies, Nuclear Corrosion, and Nuclear Corrosion Mechanisms being covered in this report.     

沿海地区汽车腐蚀的原因与防护方法探析

在沿海潮湿地区，汽车的腐蚀问题十分突出，但易被人们所忽视。通过对汽车腐蚀原因的分析，提出了一些防腐蚀方法与措施，为汽车的合理使用、正确维护保养提供参考。