Seawater, corrosion

Schumacher, M., Seawater Corrosion Handbook, Noyes Data Corptoration, Park Ridge, USA (1979)... 

It has many other uses as an abrasive, as an ingredient of cements, and as a paint pigment in the oxide form and in the paper and ink industries, in batteries for space vehicles, and wherever a metal is needed to resist chlorine (seawater) corrosion. 

Vanadium is an excellent alloy metal with iron that produces hard, strong, corrosion-resistant steel that resists most acids and alkali. It is even more resistant to seawater corrosion than is stainless steel. Vanadium is difficult to prepare in a pure form in large amounts. Impure forms seem to work as well as a very pure form of the metal when used as an alloy. When worked as a metal, it must be heated in an inert atmosphere because it will readily oxidize. 

Quite often jetties are fitted with their own water pumps, taking suction into the sea or river. The jetty fire water grid is often connected to the main plant fire water system as a backup. Care should be taken to avoid seawater corrosion of the main site fire water system. 

Design Considerations in Seawater Corrosion Protecting System... 

Properties Silvery solid or dark-gray, amorphous powder. D 4.6 (20C), mp 1675C, bp 3260C, sp heat 0.13 Btu/lb/F, thermal conductivity 105 Btu/ft2/F/ hour, as strong as steel but 45% lighter, Vickers hardness 80-100, excellent resistance to atmospheric and seawater corrosion and to corrosion by chlorine, chlorinated solvents, and sulfur compounds reactive when hot or molten. Insoluble in water, inert to nitric acid but attacked by concentrated sulfuric acid and hydrochloric acid. Unaffected by strong alkalies. 

W. H. Hartt, A. M. Rosenberg, Influence of Ca(N02)2 on Seawater Corrosion of Reinforcing Steel in Concrete , American Concrete Institute, Detroit, SP 65-33, 609-622, 1989. 

Reinforced concrete structures exposed to marine environments suffer premature corrosion-induced deterioration by chloride in seawater. Corrosion is typically found in piers and docks, bulkheads and retaining walls, mooring structures and navigational aids. 

T.P. May, H. Humble, Effectiveness of cathodic currents in reducing crevice corrosion of several materials in seawater. Corrosion 8 (1952) 50-56. 

C.A. Loto, Effect of inhibitors and admixed chloride on electrochemical corrosion behavior of nuld steel reinforcement in concrete in seawater. Corrosion 48 (1992) 159—163. 

Johnsen R, Bardal E. Cathodic properties of different stainless steels in natural seawater. Corrosion 41,1985, 296. 

Efird KD. Effects of fluid dynamics on the corrosion of copper-base alloys in seawater. Corrosion, 33, 1977 3-8. 

Tinbronze CuSnlO From C90200 Seawater-, corrosion- and cavitation-resistant, tough alloy with good wear resistance. Well suited for pumps and turbine components, fittings for high mechanical loads, and thin-walled castings. 

Seawater-, corrosion- and cavitation-resistant alloy with relatively very high strength. 

Pseudomonas spp. are IRB species reported to have corrosive effects. " - However, there is an increasing body of evidence that IRB could actually slow down corrosion. Hernandez et al. reported that in the presence of bacteria like aerobic Pseudomonas sp. and facultative anaerobic Serratia marcescens in synthetic seawater, corrosion of mild steel is inhibited. The effect seemed to disappear with time in natural seawater. Although no particular mechanism was proposed to address this phenomenon, it seems that it is related to the biofilm produced, thus reducing the contribution of factors such as diffusion gradients that normally enhance corrosion. 

B. Todd. Materials selection for high reliability copper alloy sea water system. Copper Development Association, www.copper.org/application/marine/seawater corrosion.html. 

Kessler, R.J., Powers, R.G. and Lasa, L.R. (1995). Update on Sacrificial Anode Cathodic Protection of Steel Reinforced Concrete Structures in Seawater. Corrosion 95, Paper 516, NACE International, Houston, TX. 

Discussion on materials for steam-water drcuit is in progress. Titanium has been selected for condenser tubing because of its enhanced resistance against seawater corrosion and extensive world wide experience. 

B. C. Syiett and D. D. Macdonald [1979] The Validity of Electrochemical Methods for Measuring Corrosion Rates of Copper-Nickel Alloys in Seawater, Corrosion 35, 505-508. 

A basic study by Bohm and Willert (1977) on hot dip galvanized zinc coatings on steel in flowing seawater showed that the attack on the zinc and time dependence of seawater corrosion of the hot dip galvanized steel was influenced by the structure of the galvanized layer. Fanning out of the 5 phase is to be avoided even growth of each layer is desirable. 

Waldron, L. J., and Peterson, M. H. (I960). Effect of iron, aluminum and cadmium additions on performance of zinc anodes in seawater. Corrosion, 16, 375t-379t. 

The number of replicate test specimens depends upon the desired reliability of the results of the test. ASTM G 16 gives guidance for establishing the required number of replicate specimens. In general, as recommended in ASTM G 52, triplicate specimens for each exposure period are sufficient for many seawater corrosion tests. 

Wilde, B. E., A Critical Appraisal of Some Popular Laboratory Electrochemical Test for Predicting the Localized Corrosion Resistance of Stainless Alloys in Seawater, Corrosion, Vol. 28, No. 8, 1972, pp. 283-291. 

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