Science Fair Project Encyclopedia
Brass is a valuable manufacturing material because of its hardness and workability. Alpha brasses , with less than 40% zinc, are malleable and can be worked cold. Beta brasses , with a higher zinc content, can only be worked hot, but are harder and stronger. White brass , with more than 45% zinc, is too brittle for general use. Some types of brass have other metals added to modify their properties.
Brass has been known to man since prehistoric times, long before zinc itself was discovered. It was produced by melting copper together with calamine, a zinc ore. During this process, the zinc is extracted from the calamine and instantly mixes with the copper. Pure zinc, on the other hand, is too reactive to be produced by ancient metalworking techniques.
In the King James version of the Bible, there are different versions of brass mentioned. In 2 Chronicles, (written around 400 to 500 BC) 4vs16 speaks of a "bright brass" in the verse, "The pots also, and the shovels, and the fleshhooks, and all their instrumnents, did Hu'ram his father make to king Solomon for the house of the LORD of bright brass."
- Prince's metal — an alpha brass.
- Bronze — an alloy of copper with tin.
- Cupronickel — an alloy of copper with nickel.
- Brass instrument — a musical instrument usually made of brass.
- Brass rubbing — reproduction of brasses, commemorative plates laid down in British and European churches from the 13th Century onwards.
- In the military, the brass are senior officers, who wear metal adornments sometimes made of brass.
- Brass refers to empty shell casings ejected from a firearm.
The contents of this article is licensed from www.wikipedia.org under the GNU Free Documentation License. Click here to see the transparent copy and copyright details