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Corrosion Basics—Corrosion Damage in Reinforced Concrete

The main causes of corrosion of steel in concrete are chloride attack and carbonation. These two mechanisms are unusual in that they do not attack the integrity of the concrete. Instead, aggressive chemical species pass through the pores in the concrete and attack the steel. This is unlike normal deterioration processes resulting from chemical attack on concrete.

Corrosion Basics—Types of Corrosive Atmospheres

Although atmospheres can be classified into four basic types, most of them are mixed and present no clear lines of demarcation. Furthermore, the type of atmosphere may vary with the wind pattern, particularly where corrosive pollutants are concerned.

Corrosion Basics—Corrosion Surveys

Two of the most fundamental and informative field measurements are soil resistivity surveys and pipe-to-soil potential surveys.

Corrosion Basics—Water Constituents

In water, the concentrations of various substances in dissolved, colloidal, or suspended form are typically low, but may vary considerably depending on the components and usage. For example, hardness values of up to 400 parts per million of calcium carbonate is sometimes tolerated in public supplies of potable water, whereas 1 ppm of dissolved iron would be unacceptable.

Corrosion Basics: Protecting Fixed Structures in Seawater

Steel structures such as bulkheads, piles, offshore drilling platforms, etc., may be protected with either sacrificial galvanic anode or impressed current cathodic protection systems.

Corrosion Basics: Coating Condition Surveys

Several elements of preplanning are necessary to effectively execute the condition survey. The first is a logical breakdown of the facility, and the second is to have a grading system to evaluate the observed conditions.

Corrosion Basics—Why Metals Corrode

Corrosion failures are often subtle and a result of invisible localized effects in the form of pits, intergranular corrosion, or attack within crevices.

Corrosion Management and Associated Implementation Issues

Any corrosion management implementation process should comprise three phases: pre-implementation, implementation, and post-implementation. Any shortcomings will adversely affect the outcome, effectiveness, and quality of the process. This article discusses corrosion management implementation issues and shortcomings that were observed during various campaigns or audits from around the world.

Corrosion Basics—Safe Application of Protective Coatings

In every industrial environment, the safety factor is an important consideration. In some environments, including the application of protective coatings, it is of overriding importance. This article explores many of the safety factors that need to be considered.

Corrosion Basics: Inhibitors for Waters of Low to Moderate Salt Concentrations

It is important to maintain inhibitor concentrations at a safe level in waters containing dissolved salts, particularly if these include chlorides.

Corrosion Basics: Engineering Materials

Although the primary focus of a corrosion engineer is on the chemical stability and corrosion resistance of these materials, it is critical to cooperate with other design team members familiar with the mechanical, physical, and other properties to ensure that the desired materials performance can be achieved.

Corrosion Basics: Cautionary Use of Test Data

Experience has shown that even when impossible circumstances appear to be present, substantial cost savings are possible by intelligent use of corrosion data and good design practices.

Corrosion Basics—Open Recirculated Cooling Water Systems

There are certain fundamental considerations that should be understood in relation to open recirculated systems, starting with the concept of cycles of concentration. If three cups of boiling water in a tea kettle were allowed to boil away to one cup, the residual cup would contain a three-fold concentration of soluble water salts, assuming that only steam was driven off.

Corrosion Basics: Steam Generation in Power Plants

The greatest use of high-temperature water and steam is in electrical power generation. Historically, fossil fuels were used almost exclusively to heat water and make steam until the introduction of nuclear power steam generators in the second part of the 20th century.

Corrosion Basics: Corrosion and the Environment

Corrosion Basics don’t get any more basic than the definition of corrosion as the deterioration of a material, usually a metal, that results from a chemical or electrochemical reaction with its environment. Almost all materials should be expected to deteriorate, to some extent, with time when exposed to the elements. Corrosion is a perfectly natural process, as natural as water flowing downhill.