The Solution

So the Stainless Steel has corroded or has just been welded....what next?

The experts are all agree that chemical treatment of Stainless Steel provides a better restoration of stainless steels natural self protection properties than other methods used on the market.

Research on this shows chemical treatment is more effective than polishing with grit, grinding, brushing or blasting. See below graph and pictures of comparative methods.

Cleaning First

Cleaning should always come first. Grease, coolant and other contaminants must be thoroughly cleaned from the surface. ICS can recommend an Avesta product to assist with this cleaning process to ensure all of the contaminants are removed.

Sometimes a fabricator/operator might skip the basic cleaning, assuming erroneously that by simply immersing the grease-laden part in an acid bath, both cleaning and passivating will take place simultaneously. That doesn't happen. Instead, the contaminating grease Pickling & Passivation processes. reacts with the acid to form gas bubbles. Bubbles on the surface of the workpiece interfere with passivation.

Even worse, contamination of the passivating solution, sometimes with high levels of chlorides, can cause a 'flash attack' - Instead of obtaining 600 the desired oxide film with a shiny, clean, corrosion-resisting surface, the flash attack causes a heavily etched or darkened surface - a deterioration of the very surface that passivation is designed to optimize.

Pickling Next

Pickling is the next step after cleaning. ICS uses well known and reputable Avesta pickling chemicals to complete this process.

Passivation to Finish

Passivation remains a critical step in maximizing the essential corrosion resistance of components made from stainless steels. It can make the difference between satisfactory performance and premature failure. Incorrectly performed, passivation can actually induce corrosion.

Passivation is a post-fabrication method of maximizing the inherent corrosion resistance of the alloy. It is not a scale removal treatment, nor is it like a coat of paint.

There is no universal agreement on the precise mechanics of how passivation works. But it is certain that a protective oxide film is present on the surface of passive stainless steel. This invisible film is considered to be extremely thin, less than 0.0000001 inch thick, which is about 1/100,000 the thickness of a human hair!

Above: A sample of the range of Avesta chemicals supplied by ICS.

ICS exclusively suppliers the tried and proven Avesta brand of chemicals for all of our Pickling & Passivation processes.

Ask ICS about the right chemicals for your job!

All research indicates Chemical Treatment is by far the best method of treating stainless steel to ensure its natural corrosion resistance properties are restored.

Grinding	Polishing	Pickling