CAUSES OF CORROSION IN STRUCTURAL STEEL AND OTHER METALS
Corrosion in metals is one of the biggest concerns for any manufacturing unit, contributing single-handedly to manufacturing inefficiency and, endangering the safety of the unit itself and the neighbourhood. Knowing what corrodes the metal in question is as important as protecting those assets from corrosion.
Once corrosion sets in it can be difficult and expensive to repair. The earlier corrosion control methods are applied, the better. Because corrosion varies widely from metal to metal and by causative factors, it is important to understand that each type of corrosion needs to be serviced keeping in mind their metal type, cause and the environment it will continue to operate in. For example, anticorrosive that acts as a water barrier is not enough to protect the metal from electric currents or bacteria.
Cause of corrosion
BASIC CORROSION
- 1. The process of basic corrosion is part chemical and part electrical. It requires a combination of moisture and oxygen. The most common cause of corrosion is the formation of rust (Iron Oxide) on the surface of metals containing iron when they come into contact with Oxygen. When there is no barrier between the iron and the water/oxygen molecules, electrochemical reaction will take place and the steel will continue to react.
- 2. Corrosion can also occur with metals such as steel are placed under too much stress, where the material could begin to crack allowing external to act up on it.
- 3. Just like exposure to oxygen rusts metal, so does hydrogen exposure.
- 4. Metals that are exposed to electrical currents can begin to experience electronic corrosion.
- 5. Metals which are exposed to dirt and bacteria can also begin to show signs of corrosion.
BIMETALLIC CORROSION
A second type of corrosion that affects steel is bimetallic corrosion. This is the type of erosion that happens as a chemical reaction when two metals come into contact with each other. Common in metal alloys, this type of corrosion is very complex, varying based on the two metals' respective combining ratios in the alloy.
ENVIRONMENTAL CORROSION
Environmental pollutants, toxins and compounds, sea water, bacteria, etc. can induce, speed up and damage metallic structures by corrosion. In such cases, the location of the metallic structure will play a huge in role in defining the corrosion control mechanis,m that will be applied.
While corrosion is a complex process, preventing it is not. Performing due diligence in the design phase, combining them with corrosion prevention methods in the initial stage itself can save plenty of issues for the business. The thing to remember about corrosion control and corrosion itself is that the earlier it is treated, the better.