plasma coating

[thryll]

Does anyone know of a company which can plasma coat inside a two inch ID pipe as they do in turbine coating. The pipe is approx 54 inches long, hastalloy X material and will be heated up to 1700 C I am currently using extruded alumina tube but it is very fragile. I would like to switch to a high temp alloy. possible? The pipe needs to be 100% protected against corrosion inside. Diffusion alluminide bond coat, outer coating partially stabilized zirconia?
Conmments please
Thanks guys and gals

 

[TVP]

Try IonBond Inc. Their website is

http://www.ionbond.com/.

 

[radomir]

There is something called "pack aluminizing" (at least RR uses that terminology) utilized to protect turbine blade airfoils from high temperature corrosion. It is neither a plasma spray procedure nor something fancy it is an old fashioned thermal (heat treatment) procedure. A part (made of a superalloy), having a surface requiring protective coating unmasked, is submerged in a vessel filled with Al2O3. Vessel is then placed in an oven heated up to 1100°C for couple of hours (not quite sure about the exact temperature and time figures but pretty close).

After removing from the oven and taking out of the vessel the part is re-heat treated at 1250°C. That is a diffusion heat treatment and that’s it. I am sure that the coating withstands 1500°C but possibly it can be used beyond and above.

There is also a more sophisticated process-coating used for combustion chamber protection SermaLoy J. It is a patent of Sermatech Inc so you can try them too.