Steel Finishing: Passivation Vs. Electropolishing
It is very important to choose the right finish for your stainless steel. Choosing the right finish can improve the functionality of the final product. In this article, we explore two popular finishes: passivation and electro polishing. Some people often confuse these two finishes because they both involve the removal of contaminants from the metal surface as opposed to adding a different material to it. In this article, we dispel some doubts about their differences.
The process of electropolishing involves a temperature-controlled bath of electrolytes and an electric current that helps strip the top layer of the metal surface. So the final result is a smooth surface with no features. In fact, the finish is so smooth that the material is almost perfectly nonstick in the end. This means that electropolished materials are also generally very easy to clean.
One of the main advantages of electropolishing is that it is easy to use even on very complicated shapes and does not take much time, making it a cost-effective finishing solution.
Like electropolishing, passivation also involves the use of a chemical bath. There is no use of any electric current to dissolve the surface layer of the metal used in this method; it is a non-electrolytic process. The iron is removed from the surface, thus making the final product more rust proof. The process of passivation, unlike electropolishing, does not lead to any alteration to the appearance of the material.
Passivation does come with one disadvantage: it is necessary to know exactly what alloy of stainless steel is being treated because the wrong solution could simply cause damage to the material.
What is Better?
Most of the time, electropolishing would be the better option to go with: it is easier to control, it is faster, and it can be applied very easily to many different stainless steel alloys. Furthermore, passivation leaves behind a discoloration, which electropolishing can remove.
However, sometimes, passivation is the better choice. Since passivation can change the composition of the oxide layer that keeps the stainless steel from rusting, it can be used to further improve the steel’s resistance to corrosion. Based on whether your priority is a smooth surface that is free of defects that is easy to clean or a metal with changed resistance to corrosion, you will need to pick between these two methods.
Look no further for your steel finishing needs. Diamond Brite is the metal polishing company that will help you pick the right finish.