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Published: 04/10/2018

Passivation of Stainless Steel

Passivation of Stainless Steel is critical for maximising corrosion resistance.

Stainless Steel has the ability to self-passivate but self-passivation can only occur when a clean surface is exposed to an environment which provides enough oxygen to form the chromium rich oxide surface layer. The layer acts as a protective armour for the steel.

It is commonly found that during manufacturing it is extremely difficult to maintain the standard of cleanliness needed to self-passivate. Fragments of mild steel, dirt or scale accumulated from cutting tools can be transferred into the surface of the steel, damaging the oxide layer and identifying the need for “pickling”.

Pickling involves the chemical removal of contamination. Hydrofluoric Acid, commonly known as pickling gel, is often used to remove the excess dirt particles. The steel is coated in the gel and then rinsed thoroughly. Once the gel is removed, the steel will immediately self-passivate; restoring the natural aesthetics and corrosion resistance.

Unlike many of our competitors who manufacture mild steel and stainless steel products on the same machinery, Electrix only manufactures Stainless Steel products which eliminates the risk of cross contamination with mild steel fragments, greatly reducing the need to re-passivate our products.