plating, anodizing, & finishing Q&As since 1989
Passivation of 420 Stainless Steel
Q. Can nitric-acid passivation process make 420 Stainless steel as corrosion resistant as 316? Please comment. Many thanks.Kwok-wai CHOOK
- Hong Kong, China
Sorry, Mr. Chook, it won't work. 316 is a very high grade of chemically resistant stainless steel. Passivation of 420 will help deter flash rusting, but it won't turn 420 into 316.
Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
I was a surgical instrument repair/maker for over 20 years.The industry used 410 and 420 series for cutting tools due its ability to hold an edge, and 316 series to make rods and screws for putting people back together. Just pull out a chart showing the difference in composition of both and the reason is quite apparent.
Best wishes,al mullins
- Fayetteville, Georgia