Dezincification of Bronze

Looking for information on controlling dezincification (boil off of zinc) while at high temp 1670 degrees F. It's a bronze clad steel that requires the temp for annealing.
TIA,
Joe

Joe Smolen wrote:
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Zinc in bronze? Please specify your bronze.
Michael Dahms
BTW: International units, please!

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Interesting - I take it that this "bronze" cladding is far from a simple bronze alloy and has zinc in it as well as tin ?
Historically (pre WW2) it was practice in shipyards (admiralty brass fittings) to whitewash brass and bronze castings before any heat treatment, to reduce this dezincification. Although dezincifiation is generally thought of as simple sublimation owing to the heat, it seems there's a chemical aspect to it as well and keeping oxygen away will reduce it.

If you are sure the bronze you have is a zinc bearing bronze, you might try to create a zinc partial pressure in your heat treat chamber by loading it with some pure zinc before you put your zinc clad part in there.. you say its clad do you know the cladding process ??? just be careful if it was brazed on you don't want to melt the braze if its there or maybe you create some other type of barrier, like nickel plate that you would remove later !!
Tom C
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