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How to strip TiC from stainless steel?

Can anybody tell me how to decoat TiC coating,which was deposited on the ss by PVD? I tried KOH and H₂O₂,but can not decoat it completely.Can anybody help me?

Wayne Xue
- SHENZHEN, CHINA
2007

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2007

Dear Xue,

I Can able to give one more idea. please try this as a trial.According to me it will strip completely.

For 1 lit H₂O₂ Add 5-10 gm of KOH and 50 gms of EDTA at Normal temperature.

Regards
Murali

A.Murali Krishna
pvd process engineer
Pune, India

But H₂O₂ is easy to decompose into H₂O and O2, especially when the temperature of the solution rises up. I know TiC can be gotten rid of with HF/HNO₃ or HCl/ HNO₃ mixtures. But HF and HNO₃ and HCl are volatile and dangerous. Can we use other steady and safe agents instead?

Robin Chen
- ShengZhen, China
2007

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2007

If we condemn HCl as dangerous but ask for something that is safe but capable of rapidly and completely dissolving titanium carbide, what does that actually mean? You don't dissolve stable solids like silicon carbide with mother's milk :-)

I think Murali has probably offered the best solution, although it may be possible to use a stabilized H₂O₂ in lieu of pure H₂O₂. Good luck!

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey

Thanks a lot for Murali's advice.

Wayne Xue
- SHENZHEN, CHINA
2007

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Safe is relative. I still bear the scars from an "oops" with pure 70% H₂O₂ (stabilized).
Try a mixture of 3 parts concentrated nitric acid with 7 parts of DI water and add 1 pound per gal of ammonium bifluoride. This is relatively benign after the dilution. You will need some fume extraction, but not much.

James Watts
- Navarre, Florida
2007

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2007

Dear Robin,

I suggested you to maintain this stripping solution at Room temperature.
The solution Temp will increase in the final stage (white fumes) , when the substrate is completely stripped off.

Have you tried it.If it is then I'll have a feedback.
Otherwise I will suggest you one more.

Thanks , you will get success

Regards
Murali

A.Murali Krishna
pvd process engineer
Pune, India