Aluminium and its alloys Aluminium corrosion Atmospheric corrosion of aluminium Corrosion in water The action of mineral products The action of organic products The effect of different environments appendices

Corrosion of Aluminium

Corrosion is a major cause of structural deterioration in marine and offshore structures. It affects the life of process equipment and pipelines, and can result in structural failure, leakage, product loss, environmental pollution and the loss of life. Pitting corrosion is regarded as one of the most hazardous forms of corrosion for marine and offshore structures. The total loss of the structure might be very small, but local rate of attack can be very large and can lead to early catastrophic failure. Pitting corrosion is a localized accelerated dissolution of metal that occurs as a result of a breakdown in the protective passive film on the metal surface. It has been studied for many years; however, the structural failure due to pit characteristics is still not fully understood. Accurate pit depth measurements, precise strength assessment techniques, risk analysis due to pitting, and the mathematical relationship of the environmental factors that causes pitting failure are also factors, which need further understanding. Hence this paper focuses on these issues. It reviews and analyses the current understanding of the pitting corrosion mechanism and investigates all possible factors that can cause pitting corrosion. Furthermore, different techniques employed by scientists and researchers to identify and model the pitting corrosion are also reviewed and analysed. Future work should involve an in-depth scientific study of the corrosion mechanism and an engineering predictive model is recommended in order to assess failure, and thereby attempt to increase the remaining life of offshore assets.

Modelling of pitting corrosion in marine and offshore steel structures – A technical review

http://digital.csic.es/bitstream/10261/84741/1/weathering%20steels_1.pdf

Atmospheric corrosion data of weathering steels. A review

Probabilistic estimation of remaining life of a pipeline in the presence of active corrosion defects

The prediction of atmospheric corrosion from meteorological and pollution parameters—I. Annual corrosion

Corrosion of ten structural steels exposed to tropical sea and fresh waters has been evaluated following an eight-year exposure period. The severity of corrosion is compared between the na...

Part 3—Underwater Corrosion of Ten Structural Steels Corrosion of Metals in Tropical Environments

Results of 16-year tests of metals in tropical sea water total and intermittent immersion and atmospheres are reported. Data are tabulated on carbon and low-alloy steels, alpha and beta brasses, bronzes, NiCu and CuNi, austenitic stainless steels, and commercially pure Al, Cu, Ni, Pb, and Zn, both as single metals and in many combinations of couples both in water and atmospheres. Data recorded include both weight loss and tensile strength as well as statistical summaries of pitting. While many of the data have been reported previously, this report gives first information on cast bronzes, and atmospheric exposures of weathering steel. Some anomalies are reported and bimetallic couple results are reported for the first time also. In addition to confirmation of results from other studies, some of the data contradict or modify conclusions reached earlier for the same materials, especially with respect to exposures elsewhere than in the tropics. This is the final report on the project.

Corrosion of metals in tropical environments. final report of 16-year exposures

Eight-year exposure tests of six stainless steels to underwater and atmospheric environments in Panama Canal Zone are described. Test environments included sea water immersion, lake water immersion, seashore inland, inland, sea water mean tide, and seashore. Structural steels, phosphor bronze and naval brass were also evaluated for comparison. Stainless steel plates later were galvanically coupled to carbon steel strips for testing in tropical waters. Stainless steels were not recommended for sea water service where perforation of structure is a consideration. They gave excellent results, however, in tropical fresh water. Tropical atmospheres appeared more corrosive to stainless steels than did temperate climates. 4.2.7, 6.2.5

Corrosion of Metals in Tropical Environments

Corrosion data are reported for 20 structural ferrous metals exposed up to 16 yr in natural tropical waters, including seawater, fresh water and mean tide elevation. Time- corrosion curves derived from both weight loss and pitting are presented for many of the ferrous alloys and tabulated data for all metal environment combinations are included. These comprehensive long term results comprise the most extensive collection of accurate seawater and fresh water corrosion data presently available.

Corrosion of metals in tropical waters, structural ferrous metals

Results are reported of 8-year exposure tests made to determine the corrosion characteristics of ten structural steels exposed to seashore and inland environments in the Panama Canal Zone. These corrosion rates are compared with existing data for the same materials in temperate zones. Data reported include a summary of individual analyses of air samples obtained at atmospheric test sites, and extensive weight-loss and pitting data for the ten steels at 1, 2, 4 and 8-year exposure intervals. Numerous time-corrosion curves in tropical marine and tropical inland exposures are given for the steels. Considerable attention is given to the effect of low-alloy additions on mild carbon steel. It was found that the corrosion of copper steel in the two tropical atmospheres was only 13 percent and 14 percent less than that of the unalloyed mild steel. The 2 percent and 5 percent nickel steels were very effective in resisting corrosion as was nickel steel. The four proprietary low-alloy steels tested displaye...

A. L. Alexander

Papers

Part 3—Underwater Corrosion of Ten Structural Steels Corrosion of Metals in Tropical Environments

Corrosion of metals in tropical environments. final report of 16-year exposures

Corrosion of Metals in Tropical Environments

Corrosion of metals in tropical waters, structural ferrous metals

Corrosion of Metals in Tropical Environments (Part 2—Atmospheric Corrosion of Ten Structural Steels)