Monday, March 15, 2010

Click on a question at right to show or hide the answer.	Is it possible to Electropolish the internal area of any component? Any internal area may be Electropolished, if an access to the area is available and a cathode can be inserted into the area while filled with Electrolyte.
	Can small parts be economically Electropolished? Small components may be Electropolished at CELCO. We have tooling that can handle 1/8” dental pieces, contact pins .06 in diameter, shim stock sizes to .001 inch thick and cannula pieces to 27 gauge. CELCO has automated tooling that enables us to handle quantities that others can’t.
	Can large parts be Electropolished? We can electropolish most any size if we can fill the inside with electrolyte or submerge the component in a bath of electrolyte. Our largest projects include: a tower 42 inches in diameter by 54 feet long, the inside of a 12 foot diameter vessel, and a trough 36 feet long with a conveyer screw.
	What materials can be Electropolished? The material that is most commonly Electropolished is stainless steel. Other alloys can be polished including, high nickel alloys, aluminum may be polished, high carbon alloys can be smoothed, but electropolishing offers little advantage in brightening the surface. Many exotic alloys may benefit from electropolishing such as Monels, Inconels, and Hastalloys.
	Electropolishing Cost? When comparing Electropolishing to mechanical finishing, electropolishing costs can be less than one-third the cost of mechanical finishing alone. Electropolishing also adds the advantage of passivation at no extra cost.
	Does Passivation produce a smooth finish on the surface of the component? Passivation does not produce a smoother finish. The passivation process removes iron and creates an oxide layer, which increases the surface RA slightly.
	Does Passivation remove weld burn and scale? CELCO performs a process called Pickle-Passivation in which the weld burn, scale and other stains are removed.
	How deep into the material does the Passivation process go? A normal passivation procedure will affect 0.0002" deep into the material.
	Does Nitric Passivation create a permanent Passive surface? Stainless steel by nature is corrosion resistant, after stainless steel is passivated it is even more corrosion resistant because of the iron removal from the surface and the oxide layer produced by the passivation process. This protective oxide layer can be damaged or removed by abrasion or exposure to some elements. But overall, passivated surfaces are very durable.