Steel is stronger and lighter than ever before. In fact, the 83,000 tons of steel needed for the Golden Gate Bridge is twice the amount that would be needed today. But all metal is susceptible to corrosion. Whether it’s steel, iron, or titanium, proper corrosion protection is absolutely essential. Galvanized and electroplated metals may offer a great deal of corrosion protection, but can any one type of coating protect against all the different kinds of corrosion that affect stainless steel?
Let’s take a look at a few of the most common types of corrosion and what tools are needed to combat them.
Galvanic Corrosion
Galvanic corrosion is one of the most common types of corrosion, and occurs then to metals with different electrochemical charges are connected using a conductive path. The corrosion itself occurs as a result of metal ions moving from anodized metal to cathodized metal. This causes one metal to corrode faster than the other. Without the electric current, these metals would corrode at the same rate, which constitutes general corrosion.
Localized Corrosion
Localized corrosion occurs when a specific area of a metal part is corroded. For example, if one small portion of a piece of steel is exposed to a steady stream of a corrosive agent, only that area will suffer. Of course, elements like stress, fatigue, and wear will all play a part in how quickly the corrosion advances.
General Corrosion
You may recognize this process if you were to see it on the bottom of a car or in an old building; it’s better known as rust. This process occurs when metal — steel or iron if you want to get into specifics — is exposed to water, thus oxidizing the surface. This allows the metal to break down, but can be prevented with galvanizing or another metal coating process.
While it’s important to protect metals, it’s just as important to know what you’re protecting them from. If you’re unsure what corrosive elements could plague metal, this handy guide should give you a head start on your research.