COPPER BERYLLIUM

Any of a group of copper-tin alloys usually containing 0.5–10% of tin. They are generally harder, stronger in compression, and more corrosion resistant than brass. Zinc is often added, as in gunmetal (2–4% zinc), to increase strength and corrosion-resistance; bronze coins often contain more zinc (2.5%) than tin (0.5%). The presence of lead improves its machining qualities. Some copper-rich alloys containing no tin are also called bronzes.

Beryllium copper is not really a compound, but a very useful alloy that often contains other metals such as cobalt or nickel in small amounts. It is a hard, strong alloy with excellent electrical conductivity, which makes it very useful in electrical switching equipment owing to its nonsparking qualities. It makes excellent spot-welding electrodes, springs, and metal bushings, cams, and diaphragms.