Effectiveness of Corrosion Inhibitors

The available literature allows us to conclude that admixed inhibitors with the correct dosage can strongly delay the onset of chloride-induced corrosion. Once corrosion started, no significant reduction in corrosion rate has been found. The overall performance of surface-applied organic and inorganic corrosion inhibitors intended to reduce ongoing chloride-induced corrosion cannot be considered positive. For the case of corrosion due to carbonation there remain at least some doubts. 

The use of corrosion inhibitors could be a promising technique in restoring reinforced concrete structures, offering benefits as reduced costs and inconvenience of repairs. It has, however, to be taken into account that the use of corrosion inhibitors in repair systems is far less well-established than their application as admixtures in new structures. The performance of proprietary corrosion inhibitors in repair systems marketed under different trade names is not yet sufficiently documented by independent research work, especially when considering field tests. 

Malric, Preliminary testing of Na2P03p as a curative corrosion inhibitor for steel reinforcements in concrete. Cement and Concrete Research, 1992, 22, 869. 

Spencer, Combined XPS and ToF-SIMS analyses in the study of inhibitor function - organic films on iron . Analysis, 1997, 25 (5), M30. 

Hansson, Corrosion inhibitors in concrete. Part III Effect on time to chloride-induced corrosion initiation and subsequent corrosion rates of steel in mortar . Cement and Concrete Research, 2001, 31, 713. 

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Corrosion inhibitors are substances which slow down or prevent corrosion when added to an environment in which a metal usually corrodes. Corrosion inhibitors are usually added to a system in small amounts either continuously or intermittently. The effectiveness of corrosion inhibitors is partiy dependent on the metals or alloys to be protected as well as the severity of the environment. For example, the main factors which must be considered before apphcation of a corrosion inhibitor to an aqueous system are the compatibility of the inhibitor and the metal(s), the salt concentration, the pH, the dissolved oxygen concentration, and the concentration of interfering species such as chlorides or metal cations. In addition, many inhibitors, most notably chromates, are toxic and environmental regulations limit use. Attention is now being given to the development of more environmentally compatible inhibitors (37). 

To reduce the effects of corrosion, inhibitors are added, typically sodium chromate in the salt brines and sodium phosphate in the glycols. These are alkaline salts and help to counteract the effects of oxidation, but periodic checks should be taken, and borax or similar alkali added if the pH value falls below 7.0 or 7.5 [1]. 

What is the effect of corrosion inhibitor on the hydrophobicity of copper surface What is the effect of change in hydrophobicity on the material removal rate and static etch rate of copper ... 

What is the effect of corrosion inhibitor on the post-CMP cleaning ... 

Inhibited polymer coatings, i.e. coatings whose components are metal corrosion inhibitors, have a long previous history. Apparent successes in the application of inhibited coatings have intermingled with conspicuous failures. It is believed that the main reason for this was the contradictory effect of corrosion inhibitors on a combination of coating performance factors. 

The Effect of Corrosion Inhibitors on Thermal Oxidation of Polymers... 

Duncan KE, Perez-Ibarra BM, Jenneman G, Harris JB, Webb R, Sublette K (2014) The effect of corrosion inhibitors on microbial communities associated with corrosion in a model flow cell system. Appl Microbiol Biotechnol 98 907-918... 

Explosive decompression High-pressure extrusion Effect of corrosion inhibitors Effect of hydrogen sulphide Steam/add resistance Methanol resistance... 

Corrosion inhibitors for steels are being continuously developed because of the ubiquitous use of steel in construction and its somewhat limited corrosion resistance, especially in the presence of water. A great number of papers are on the effect of corrosion inhibitors, and the overwhelming majority deals with the effect of inhibitors on uniform corrosion. Due to environmental restrictions on common inorganic inhibitors (Freedman, 1986), several studies suggest derivatives of some amino acids as corrosion inhibitors. A survey of a number of different organic compounds commonly used as uniform corrosion inhibitors showed that most compounds hardly affect the pitting corrosion of stainless steel however, one of... 

Sorochenko, V. F., Shutko, A. R, Pavlenko, N., Bukolova, T. P. (1984). The effectiveness of corrosion inhibitors in water recycling systems. Chemistry and technology... 

Designing tests to effectively evaluate the effects of corrosion inhibitors on localized corrosion is a highly challenging task. This is illustrated by a practical case of developing a test for evaluating the performance of underdeposit carbon dioxide corrosion inhibitors imder simulated oil pipeline conditions. Corrosion... 

In the real world corrosion rates always change with time, for instance some forms of localized corrosion such as microbiologically influenced corrosion can accelerate rapidly and grow exponentially once initiated, and therefore it is important to identify the specific time periods of maximum corrosion rates and the effects of corrosion inhibitors. For this reason instantaneous techniques are important for continuous measirrement of the prevailing corrosion rates for... 

When no current is applied and the working electrode has achieved a steady state, then the potential is the corrosion potential, E, of the electrode material. The corrosion potential is the mixed potential to which the anodes and cathodes are polarized by the corrosion reaction. It is also an indication of the effects of corrosion inhibitors. 

M. Foss, E. Gulbrandsen, J. Sjoblom 2009. Effect of corrosion inhibitors and oil on carbon dioxide corrosion and wetting of carbon steel with ferrous carbonate deposits. Corrosion 65 (1), 3-14. W. Fulton, J. Harris 1991. Representation Theory A First Course, Graduate Texts in Mathematics, Readings in Mathematics, 129, Springer-Verlag, New York. 

The effect of corrosion inhibitor is used directly in the calculation and defined as inhibitor efficiency. If the inhibitor efficiency is 90%, the corrosion rate will be reduced 10-fold. 

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