Where the
world gathers for metal finishing
Q&As since 1989


-----

Stainless steel acid wash applied to regular steel

does it serve any purpose or create any damage if you use the stainless steel acid wash application on regular steel? it appeared to discolor almost like rusting?

Jim Arboit
employee - Normal, Illinois
October 20, 2010

---

Hi, Jim

Unfortunately, the "stainless steel acid wash" doesn't say much about what it actually is. But in general, dipping steel into acid will leave it highly prone to flash rusting. You need to be very careful about such things, though, dipping plain steel into nitric acid mixtures that are commonly used for pickling or passivating steel can evolve clouds of poisonous NOx.

Regards,

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
October 20, 2010

---

The sole purpose of stainless steel passivation baths is to dissolve iron, so they will readily etch carbon steel. Occasionally this is what is desired, a quick dip in citric acid will clean up a messy carbon steel surface pretty easily. You just have to be careful about it.

Other acids might be used for cleaning or etching purposes as well, how much of either they will accomplish depends on the type of acid and concentration and such.

I suppose the real question here is what are you trying to accomplish? If the issue is a cleaner being used on stainless steel that is adjacent to some carbon steel, and overspray is unavoidable, you may have to just cover over the carbon steel with plastic sheeting or something to protect it. I would test the cleaner on a small area of the carbon steel to see if it's going to be a problem.

Ray Kremer
Stellar Solutions, Inc.

McHenry, Illinois

October 21, 2010