How to Prevent Corrosion of Metals for FE Exam Prep Course

Anodic and cathodic reactions lead to corrosion of metals. The National Association of Corrosion Engineers (NACE) has conducted a study that shows that the USA will lose $1 trillion because of corrosion. There are several methods to prevent this corrosion that leads to a lot of losses.

The metal can be coated: You can coat the metal with another metal such as zinc, steel, or tin coatings. The source metal itself can be a source for the anti-corrosion material. For example, applying aluminium oxide on anodized aluminium. Organic coatings such as resins, paints, plastics, oils, enamels, and greases can be applied to the metal. There are many methods of protective coating such as:

Cadding

Hot dipping

Electrodepositing

Flame spraying

Ion implantation

laser glazing

Diffusion

Vapour deposition

The FE Exam covers the topic of corrosion control.

Placing Barriers: A barrier can be placed between the metal and the environment. This is the simplest and least-cost method to prevent corrosion.

Applying Alloy to the Metal: Stainless steel, for example, where steel is alloyed with chromium and nickel, prevents corrosion.

Removal of Oxygen: If oxygen is removed from the water then, it leads to reduction in corrosion. Sulphite can be used to remove oxygen.

Using Corrosion Inhibitors: Corrosion inhibitors are used to reduce metal wastage by mixing a corrosion inhibitor with a corrosive aqueous environment. There are cathodic inhibitors, anodic inhibitors, absorption type corrosion inhibitors, and mixed inhibitors. Anodic inhibitors such as nitrite and silicate are also known as dangerous inhibitors. Cathodic inhibitors such as zinc ions are called as safe inhibitors. Phosphonate and carboxyl are examples of adsorption type corrosion inhibitors. The FE Exam Prep and EIT Exam helps in learning about the methods to prevent corrosion.

Electrochemical Control: You can control the rate of corrosion by supplying current into the metal.

Selection of Metal for any Work: Select the correct metal or alloy for construction and other works. There are corrosion tables which indicate which metal will be corroded in which type of environment. Using these tables, an appropriate combination of metal and environment can be achieved. The FE Exam Preparation helps to provide more information about corrosion and its prevention.

Improvement of materials: There are several methods that improve materials and so reduce corrosion. The corrosion prone materials can be improved by purification of metals, making them noble, inhibiting, and scavenging. Change of micro structure, elimination of tensile stress, and introduction of surface compressive stress also help in improving the materials and so prevent corrosion. The FE Prep Course and EIT Exam deals with the topic of corrosion.

Carefully Design Structures: While designing structures try and avoid sharp corners. You have to drain vessels completely and reduce water retention. Avoid sudden changes in building sections, and avoid contact between dissimilar metals. It is preferable to weld rather than rivet. You have to replace vulnerable parts and avoid excessive mechanical stress.

Environment can be Altered: The temperature and velocity can be lowered. Oxygen can be removed.

Using these several methods, corrosion can be prevented and reduced. The FE Exam Prep Course deals with the topic of prevention against corrosion.