Painting Stainless Steel Alloy 304

Question:

I would like to know if it is possible to paint stainless 304 with a high solids epoxy type paint (per Mil-C-22750). If not, can you recommend a paint type that would be more suitable for this alloy. What type of primer is recommended for this surface? Also, is it possible to achieve good adhesion without any mechanical abrasion to the surface, and if not, would abrading the surface compromise the corrosion resistance properties of the stainless steel. We would prefer to prepare the surface for painting by cleaning with degreasing solvents, but will this ensure good primer adhesion? D.D.

Answer:

Generally speaking, an epoxy paint would be an excellent choice for painting stainless steel alloy 304. This statement applies to 100% solids, high solids, low solids and powder coatings. An epoxy primer would be certainly be suitable for this application. However it would be wise to abrade the surface using something that does not cause iron particles to become embedded in it. In any event, surface abrasion should be light. As an alternative, a phosphoric acid activated vinyl wash primer applied to a degreased surface and then top coated with a liquid epoxy would also be an excellent finish system.