In this weeks article, A case study examining corrosion in stainless steel alloys, Dr. Michael J. Fletcher talks about how during heat treatment surface oxide, layers are formed on precipitation-hardening nickel-based alloys such as UNS N07718. These oxide layers are composed of elements that have been selectively oxidized from the base metal, principally nickel, chromium, and iron.
Stainless steels owe their resistance to corrosion to the formation of a very thin, transparent surface layer of chromium oxide, Fletcher explains. This provides a passive film that acts as a barrier to penetration by an invasive environment.
To read the full article, please email Catarina Muia at c.muia@kci-world.com.