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Cleaning Copper Based Alloys

Can anyone give me a recommendation for replacing tri-chlor when cleaning copper based Alloys?

Dan Walk
- Altoona, Pennsylvania, USA
2001

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You should use a degreaser if metal is oily, etc. followed by a rinse. We use approximately 10% (by volume) concentrated sulfuric in water with 0.5% (vol.) 50% hydrogen peroxide based commercial deoxidizer (with stabilizers added). This solution is at a maximum of 30 deg.C., (gets heated only by chemical reaction, and cooling may be necessary). Use an immersion time that just removes oxidation (typically 1 to 5 minutes) but do not etch. Cold rinse, then hot rinse so that metal surface is left over the ambient dew point, but not above 40 deg.C., and finally use a hot air blast to dry off the water, (do this carefully controlled, so you do not retarnish the surface).

Good Luck.

W. Carl Erickson
- Rome, New York
2001