Electropolishing of 316L stainless steel for anticorrosion passivation

316L stainless steel is deemed an indispensable material in the semiconduct or industry. In many instances, the surface of the production equipment nee ds to be treated for low-corrosion passivation, good finish, weldability, a nd cleanliness. The process characteristics of electropolishing meet these requirements well. The current study investigates the effects of the major processing parameters on the anticorrosion performance and the surface roug hness. The electrolyte with 10% water content and a ratio between H2SO4 and H3PO4 of 4 and 6 has been proven to be successful, showing no corrosion pi tting points on the specimen surface. The electrolyte temperature of 85 +/- 10 degreesC and the electrical current density of 0.5 to 1.0 A/cm(2) are f ound to be optimal. The processing time beyond 3 to 5 min produces no furth er improvement. The addition of 10% glycerin provides a very fine surface ( maximum. roughness of 0.05 mum), while the anticorrosion performance is det eriorated. The results obtained are useful for the manufacture of the semic onductor equipment.