Benefits of Electropolishing for Stainless Steel & Metal Alloys
There is a wide variety of electropolishing benefits for stainless steel and other metal alloys over mechanical metal finishing processes, like hand deburring, tumbling, pickling, grinding, and milling. These methods can smear, bend, stress, or fracture metal surfaces, and are often not suited for highly detailed or fragile parts. Because electropolishing is a non-mechanical process, there is a very limited risk of distortion or other defects.
Using electropolishing to finish and perfect your stainless steel or other metal alloy parts, components and equipment provide numerous advantages over other metal finishing processes:
Relieves surface stress
Electropolishing stainless steel or other metal alloys effectively and efficiently eliminates stress defects from metal surfaces. Electropolishing eliminates surface defects to tolerances as low as +/-.0001-inch depending on the metal. The process of surface stress relief reduces microscopic peaks caused by metalworking operations like stamping, welding, and forming, and improves part performance.
Electropolishing removes cold-worked metal oxides. Mechanical cutting, machining, handling, and polishing can leave abrasive particles embedded within a metal surface. These contaminate disrupt metals from naturally forming oxidation-resistant layers. Electropolishing dissolves free iron, inclusions, and embedded particles from the surface of the material surface.
Passivates stainless steel
Electropolishing provides superior passivation for stainless steel. Passivation is a widely used metal finishing process that helps prevent corrosion. In stainless steel, passivation uses nitric acid or citric acid to remove iron particles from the surface. The chemical treatment forms a protective oxide layer that is less likely to chemically react with air and cause corrosion. Passivation removes outside free iron and iron compounds from the surface of metal, while retaining the integrity of the stainless steel. Electropolishing is considered the superior form of passivation.
Electropolishing provides long-term oxidation and corrosion resistance for many metals and alloys by eliminating surface imperfections and contaminants embedded in the metal part’s surface. Removing surface imperfections eliminates areas where moisture and contaminants can collect and lead to corrosion.
Electropolishing gives metals a smooth, clean, hygienic finish. Electropolishing both micro-polishes and macro-polishes, providing both brightness and smoothness. Electropolishing creates a uniform finish that does not peel or abrade. This clean surface enhances weldability, lowers friction, allows for easier cleaning, and improves heat and light reflection.
Electropolishing decarburizes, or decarbonizes, and dissolves iron and leaves surfaces with a higher relative concentration of chromium. This improved surface will form a thicker and more uniform oxide layer with enhanced corrosion resistance properties. Electropolished stainless steels are better suited to resist the onset of pitting corrosion, crevice corrosion, localized galvanic corrosion, stress corrosion cracking and microbiologically influenced corrosion.
Eliminates hydrogen embrittlement
The chemical bath used in electropolishing removes hydrogen from the metal’s surface, which helps protect the part against hydrogen embrittlement. This makes electropolishing ideal for processing medical, pharmaceutical, and semiconductor parts and components and equipment because no directional lines and a hydrogen-free surface provide an ultra-clean, hygienic surface that reduces and eliminates bacteria and corrosion.
Makes metal look great, easy to clean
Electropolishing gives metal a striking, gleaming, lustrous look. Electropolishing is a non-mechanical process, so no tools come in contact with the part, which means no polishing lines. Electropolishing also substantially reduces product contamination and adhesion, which decreases cleaning time for parts and components – sometimes by as much as 50 percent.