As mentioned in part one of Deterioration of stainless steel corrosion resistance due to welding, written by Fandem QA, the coarse grained heat affected zone (CGHAZ) of stainless steel got affected after welding, and the solution to recover the protection film is by performing a passivation process.
Passivation is the removal of impurities or iron from the surface, and can be achieved by electropolishing, electrochemical cleaning, or chemical passivation.
For the full article, please email Catarina Muia at c.muia@kci-world.com for the PDF.