The passivation process is a method of improving the corrosion resistance of stainless steel parts by removing ferrous contaminants like free iron from their surface, restoring them to their original corrosion specifications.
To passivate stainless steel parts, they must be submerged in a chemical solution of citric acid or nitric acid for a certain period of time and at a certain temperature. This removes foreign matter like free iron from the surface, but does not remove the heat tint or oxide scale that may be left behind by welding or heat treating. The passivation process improves corrosion resistance and leaves a clean finish, but ultimately does not change a part’s appearance nor make it visibly brighter.
By comparison, electropolishing removes burrs, heat tint and oxide scale and makes parts made from a wider variety of stainless steel and other metal alloys visibly brighter.
While you can passivate stainless steel to improve its corrosion resistance, not all grades are suited for this process, and some parts may require additional cleaning operations beforehand.
Whatever the bumps along the road, the future of the automobile industry is electric – and the future of the EV auto industry is built on the reliability, safety and performance of its batteries.
From stubborn burrs and other microscopic defects to cleanability, corrosion, and premature part failure, metal surface issues are a common manufacturing challenge.
Metal parts used in food processing machinery, including cutting blades, mixing tanks, and fittings face constant exposure to corrosive substances such as salts, acids and moisture, in addition to aggressive cleaning methods.
Manufacturers that specify electropolishing for metal parts used in medical devices, pharmaceutical production equipment, semiconductors and food processing components need more than an ultrasmooth and defect-free surface; they need those results consistently – part after part, and across the surface…