The authoritative public forum
  for Metal Finishing since 1989
  

  -----

Electropolishing of 304L SS

2007

Hi

I was wondering if electropolishing is good alternative process instead of passivation for 304L stainless steel and does electropolishing remove all the free iron without removing the Chromium?

Thanks,

Morie Rezai
Aerospace - Chandler, Arizona

---

2007

Morie:

Electropolishing is beneficial in removal of surface contamination, smoothing of the surface (produces a lower Ra finish and more cleanable surface), and some level of passivation. Post electropolishing with citric acid based chelant passivation will provide better corrosion protection with higher chromium to iron ratios on the surface. Ultra high purity applications in many industries require both electropolishing and passivation for improved corrosion protection.

Thanks,

Daryl L. Roll
Costa Mesa, California, USA