passivation of abrasive blasted stainless steel
Stainless steel passivation is a process that makes stainless steel less susceptible to corrosive environmental factors such as air and water. Learn More Abrasive Blasting
Jan 08, 2008 · The stainless steel must be re-passivated even if your abrasive is completely iron-free. A passivated stainless steel surface is chrome-enriched, and abrasive blasting will remove that enrichment. Although it is 'kinda/sorta' true that stainless steel 'passivates itself' after citric acid treatment, don't let multiple casual meanings of "passivate" lead us like a will-o'-the-wisp into a Cleaning Before Passivating Products FinishingApr 01, 2002 · If the 17-2 is in the hardened condition, it should probably be abrasive blasted to remove the oxide. Following oxide removal, it can be passivated with a standard solution of approximately 40% nitric acid between room temperature and 140F for 30-60 min. This should be followed by a thorough rinsing in clean water. Fetching next article.
Sep 01, 2021 · Stainless steel passivation services. Capable of passivating metals with 8 ft. length and 4 ft. width. Also offers bead blasting, passivation, painting, powder coating, electropolishing, rust removal, and anodizing services. MIL-S-5002C, QQ-P-35, and EPA compliant. Passivation - Millard Manufacturing, Custom Food Media Blasting is a primary clean-up method used by fabricators to remove contaminants, though it does not restore the corrosion-resistant film. Obviously, the abrasive medium has to be iron-free even sand is on the do-not-use list because it might contain iron and steel. According to the British Stainless Steel
Stainless steels, even the least alloyed, will passivate immediately upon exposure to air. This is basic physical chemistry and the rapid oxidation of chromium is the fundamental reason stainless steels are stainless. Typically the requirement arises relative to fabrication issues such as the removal of heat tint from welding or simple iron contamination from forming and fabrication. Passivation of Stainless Steel - American Welding SocietyIn layman's terms, the passivation process removes free iron contamination left behindon the surface of the stainless steel as a result of machining and fabricating processes.These contaminants are potential corrosion sites which, if not removed, result in prema-ture corrosion and ultimately result in deterioration of the component. In addition, the
Nov 01, 1998 · According to ASTM A380, passivation is "the removal of exogenous iron or iron compounds from the surface of stainless steel by means of a chemical dissolution, most typically by a treatment with an acid solution that will remove the surface contamination, but will not significantly affect the stainless steel itself." Passivation of Stainless Steelstainless steel with a mild oxidant, such as a nitric acid solution, for the purpose of enhancing the spontaneous formation of the protective passive film. In layman's terms, the passivation process removes free iron contamination left behind on the surface of the stainless steel as a result of machining and fabricating processes.
Soak 'em in 10% nitric acid solution for half an hour at 70 degrees or higher and you should be alright. You could also use citric acid if you have a disposal problem. See ASTM A967 / A967M [affil. link to spec at Techstreet] for full details or search this website for passivation. There is lots of information here.