Stainless Steel Casting

Electropolishing for Stainless Steel Castings

Stainless steel investment casting process is widely used for industrial applications because of its excellent corrosion resistance. In many cases, the surface of stainless steel castings often need to meet some special requirements, such as: low surface roughness, high gloss, matte finish, etc. By some effective surface finishing methods, such as electropolishing, satin finish or mirror polishing, it can reduce the surface roughness and increase the brightness of stainless steel castings greatly.

Electropolishing for Stainless Steel Castings

Electropolishing is a kind of electro chemical polishing process especially used for stainless steel castings. The electropolishing is based on the stainless steel castings being dropped as the anode and the insoluble metal as the cathode. The two poles are immersed into the electrolytic cell at the same time, and the anode is selectively dissolved by the direct current. The surface of stainless steel castings is gradually stabilized, so as to achieve the effect of increasing the surface brightness of stainless steel castings.

How Do Electropolishing Work?

Electropolishing procedures after stainless steel casting are similar to passivation procedures in that they use a chemical bath to help strip impurities from the surface of stainless steel castings. However, there’s one key difference—electropolishing solutions apply an electric current to the solution during the process.

When a current is run through the electrolytic solution, it causes a reaction that dissolves the surface layer of stainless steel castings being electropolished. This leaves only a microscopically-smooth, almost mirror-like surface.

Advantages of Electropolishing for Stainless Steel Castings

  • Polish areas of stainless steel castings inaccessible by other polishing methods.
  • Improve surface reflectivity and brightness of stainless steel castings.
  • Removes a small amount of material (roughly 20-40 micrometers thick) from the part surface, taking small burrs and high spots with it
  • Provides a corrosion resistant surface
  • Removes surface discoloration caused by heat treating and/or oxidation
  • Creates a bright, reflective finish
  • Provides a clean and smooth surface that is easier to sterilize

Leave a Reply

Your email address will not be published. Required fields are marked *