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Curated with aloha by
Ted Mooney, P.E. RET
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Titanium reaction with HCl and HF
We use descaler (mixture of acids : 50% HCl and 5% HF) in the titanium heat exchanger. We noticed that the titanium discolorized. By this reaction, thus it means that the metal composition of titanium (Grade 7 and 12) be attacked? Can it result in breakdown of titanium?
Ben Riva- Philippines
2006
Yes. Titanium is attacked by both acids.
Guillermo MarrufoMonterrey, NL, Mexico
2006
The discoloration may be hydrogen attack from the acids.
Suggest a 30 wt% sulfuric acid + 1% copper sulphate
⇦ this on
eBay or
Amazon [affil links] solution at 28 °C (100 °F) for cleaning, and a 33.2% nitric acid + 1.6% hydrofluoric acid solution for final brightening.
See letter 38318 and ASTM B600(2002) Standard Guide for Descaling and Cleaning Titanium and Titanium Alloy Surfaces.
- Goleta, California
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Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
2006
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