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Ted Mooney, P.E. RET

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How to measure the rate of rusting quantitatively
Q. Hello I am doing a experiment and I need to measure the rate of rust. I was thinking if I dissolved the rust then tried to find the amount of iron ion in solution however I do not know how to dissolve the rust or what chemicals I should use for the titration.
thank you
STUDENT - BRISBANE, QUEENSLAND, AUSTRALIA
2007
A. Titration for iron is problematic since both Fe(+2) & Fe(+3) will be present.
Weigh the sample coupon (a thin rectangle of some standard area is usually used) before testing. Afterwards, remove the rust & re-weigh the coupon. Corrosion can be reported in units of weight/area/time.
ASTM G1-03, 'Standard Practice for Preparing, Cleaning, and Evaluating Corrosion Test Specimens' gives some solutions for removing rust. It is probably much more practical to use an equivalent household rust remover; e.g., hydrochloric acid solution containing an inhibitor. The inhibitor is necessary to avoid loss of metal.
- Goleta, California

Rest in peace, Ken. Thank you for your hard work which the finishing world, and we at finishing.com, continue to benefit from.
Q. Where can I find the substances used to remove the rust?
ALEKS LAZAREVIC [returning]STUDENT - BRISBANE, QUEENSLAND, AUSTRALIA
Ken recommended a household product, so try C-L-R ⇦ this on eBay or Amazon [affil links] (Calcium - Lime - Rust Remover). The label says it contains water, glycolic, sulfamic & citric acid s, and surfactants.

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