HVOF T800 removal

[finnie]

I'm looking for a chemical strip method to remove roughly .005-.007 inches of HVOF T800. The base material is Rene 41 and is quite thin so grit blast strip is not my method of choice, nor do I think it's even and option.

[Gordon]

Hi finnie

to the Surface Engineering Forum.

I think this will be a difficult one to answer. The only thing I've got reference to is the use of molten sodium hydroxide (425 C), but I don't like the sound of that and probably give you as much distortion as grit blasting. You could try a typical nickel strip salt solution or electrolytic method using sodium carbonate and tartaric acid solution. To be honest I have no idea how successful they may be, but I would certainly recommend doing tests before committing components. Don't want to be left with a coating shell and no Rene 41 left

[kurtecard]

How was your coating surface prepped before coat? If you are allowed to grit blast but are worried about distorion you may have another option. It is not on the same substrate, but we have some tooling that we have to strip occasionally. I find what works well for the tooling is to heat the tooling to about 400F or so and then grit blast at very high pressure 80+psi but with very little grit flow, just enough to break you edges, the stuff lifts right off for us because of the fluxuation caused when it was heated it doesn't retain all of it bonding properties. But we can still maintain our tight tolerances because the tooling is made of a rugged enough meterial where it doesn't warp. Just an idea...