How can stainless steel rust? Isn't this an oxymoron? If you're involved in providing stainless steel products to consumers, you may wonder why you get some complaints along these lines. In truth, this could be due to a number of different causes and possibly part of the fabrication process itself. What could be the issue here and what is the answer?
Firstly, it's important to make sure that the proper grade of stainless steel is used at all times. Not only this, but the type of finish required should be specified very carefully at the outset. This will call for the right grade of abrasive to be used to finish the surface and usually, the more polished it is, the more resistant it will be to corrosion.
If welding is part of the steel fabrication, it should be remembered that this process can create an oxidisation effect known as "heat tint." This part of the surface will be less resistant to corrosion than material adjoining it. Therefore, specific finishing techniques should be applied using pastes, sprays, gels and brushes.
Carbon contamination can be a cause of what appears to be rusting. When wire brushes and other tools are used and grinding dust is evident from jobs nearby, care should be taken to segregate. Carbon steel fabrication may be part of the job, but should be conducted elsewhere. If not, the machines should be cleaned very carefully in between processes. At the absolute least, stainless steel surfaces should be protected with plastic coatings, whenever other work is taking place.
Once the job has been fabricated, the stainless steel product has to be protected carefully during its journey towards the consumer. In particular, it should not come into contact with any harsh cleaning products that are used to clean other surfaces. For example, muriatic acid is contained within some products used to clean masonry or brick and this will contaminate stainless steel right away.
A final word of advice for the client. A stainless steel product can last very well and be perfect for the job, so long as a certain amount of care is used in maintaining it. These products need to be cleaned from time to time using a simple mix of warm water and soap. Abrasive cleaning products should never be used and soft creams or polishes are indicated for tougher stains.