4 Ways to Save Your Steel from Corrosion
Steel is a very popular material in everything from construction to infrastructure to transportation solutions. The one downfall of steel is that it can corrode quickly if not looked after properly. As leading steel suppliers in Perth, Trufab has a lot of experience with corrosion and how to prevent it, so we’ve put together this guide for the proper care of steel.
There are four main types of corrosion that can occur with your steel supplies. These are:
- Uniform attack corrosion
- Galvanic corrosion
- Pitting corrosion
- Crevice corrosion
1. Fighting Uniform Attack Corrosion
With uniform attack corrosion, the entire surface corrodes at roughly the same rate. This means that any solution needs to be applied to the whole surface to protect it.
The easiest way to protect against uniform attack corrosion is to put a protective barrier between the metal and the corroding agents. You could use paint, an oil sealant, or ideally an electrochemical solution like galvanised zinc or plastic coating. If your steel is underground or immersed in liquid, cathodic protection such as sacrificial anodes is a good choice.
What Are Sacrificial Anodes?
A sacrificial anode is a small, reactive piece of metal attached to a larger steel structure. For reasons a little too technical to get into here, only the smaller piece of metal will corrode, protecting the steel.
2. Stopping Galvanic Corrosion
Galvanic corrosion can occur whenever steel is in contact with another metal that has a less-active electrode potential. The simplest way to avoid this is to not allow different metals to have direct contact, but this is not always possible. Other options include protective coatings to prevent an electrically conducting path from forming. Galvanisation and anodising are good examples of this. Electrically insulating the areas of contact also works well.
3. Putting a Stop to Pitting
Pitting corrosion occurs when small areas of steel lose their protective layer and corrode. This can be particularly problematic as these small
areas are weakened, creating structural instability. The best way to avoid this is to re-apply protective coatings regularly or use cathodic protection. If you notice damage to the protective coating, repair it as quickly as possible in accordance with AS/NZS 4680.
4. Preventing Crevice Corrosion
Crevice corrosion occurs when the gap near a metal surface is wide enough to allow fluid to enter but too narrow for easy drainage. This allows water to stagnate and become corrosive. The best treatment here is prevention – minimise corrosion by eliminating tight gaps in a metal object’s construction by closing these gaps or allowing circulation.
General Care Tips
As well as these methods for combating specific types of corrosion, here are some general tips:
- Avoid exposing steel to a pH level above 12 or below 6 for a prolonged period.
- Do not clean coated steel with abrasive products, as this can damage the coating – clean using non-abrasive products and then rinse with
- Avoid storing steel for long periods in damp or poorly ventilated areas.
For complete steel solutions and expert advice, contact the Trufab team today