The National Association of Corrosion Engineers has published the results of much research in the field of corrosion. Corrosion technology is now well established and is taking its place as another branch of engineering. Specialists are available to give advice on various methods that can be used to prevent corrosion. Their services can be of great value in the building field, especially if sought during the design stages. Revision of a specification at the planning stage may require only minor changes while changes made after a building has been completed are often very costly.
Corrosion refers to any process involving the deterioration or degradation of metal components.
The best known case is that of the rusting of steel. Corrosion processes are usually electro-chemical in nature, having the essential features of a battery. Dissimilar metals in the presence of a conducting liquid, known as the electrolyte, develop an electrical potential that causes a current to flow whenever a suitable path is provided. Such electrical potentials may also be developed between two areas of a component made of a single metal as a result of small differences in composition or structure or of differences in the conditions to which the metal surface is exposed. In the corrosion systems commonly involved in buildings there may often be only a single metal involved, with water containing some salts in solution as the electrolyte.