Posted by John Swensen on February 02, 2001 at 14:55:21:
In Reply to: Metallurgy posted by Art on February 02, 2001 at 14:27:58:
In my experience, the more zinc in a brass alloy, the more quickly the metal work-hardens (gets stronger as it is deformed). Even pure copper will work harden, though. Cartridge brass (about 70% copper, 30% zinc) is just about the easiest of metals to form (hence its use to make drawn cartridges shells for firearms), and has good strength when work-hardened.
Adding nickel to brass alloys produces a white color, such as is often seen with slide tubes and trim parts of various horns. Such nickel silvers (containing about 60% copper, 22% zinc, and 18% nickel, no silver) tend to tarnish less than straight brass, but more than silver. For example, the nickel silver trim on my Alexander F is a slightly dull grey where the lacquer has worn off over the years, but it does not have the ugly green stains from water drips that the raw brass has accumulated. If you want bright looking nickel silver, you still need to lacquer it.
Nickel silver is a lot tougher than cartridge brass, and it is more difficult to work with, but not so much so that instruments can't be made using it. Many French horns are made of nickel silver, for example. It is said to sound brighter than brass at low dynamic levels, but doesn't get as "brassy" sounding at fortissimo levels.