For centuries, metals have been the go-to choice for multiples applications due to their durability, versatility and strength. However, among the challenges that people face when using metals, corrosion is arguably the most common and widely recognized.
Multiple solutions have been proposed to increase the longevity of metallic structures and enhance their corrosion resistance. Among them, metal coatings stand out as one of the most effective and convenient protection methods.
There are numerous methods for coating metallic surfaces, each with its own set of limitations and benefits. In the following sections we will take a detailed look at some of the most common types of metal coatings, and discuss their suitability for various applications.
How Metal Coatings Protect Surfaces and Structures
Metal corrosion is a deteriorative process that occurs under specific conditions. The most common type of corrosion occurs when metals react with moisture and oxygen to create various corrosion products. Iron, for example, reacts with water and oxygen in the atmosphere to form iron (III) oxide, or rust.
The logic behind metal coatings, therefore, is to create an inert (non-reactive) barrier around the metallic object being protected to prevent it from reacting with air and moisture.
Common Types of Metal Coatings and Their Benefits
Below, we have compiled a list of the most common types of metal coatings used across various industries, and the advantages and disadvantages of each.
Anodizing is a process used to promote the formation of a protective oxide layer on the surface of a metal. The resulting oxide layer forms more rapidly and is usually thicker than if it was produced naturally. While several non-ferrous metals can be anodized, aluminum responds most effectively to this process. (Background reading: Understanding Ferrous and Non-Ferrous Metals: Why You Should Understand These Key Differences.)