Bronze

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Bronze is a metal alloy. Bronze is mostly copper, with some tin added (usually between 5% and 20% tin).

History[change | change source]

Bronze was the first alloy that was used by humans. The first nation that used Bronze was Egypt about 3500 years B.C. This gave the name for the Bronze Age.

Bronze is stronger than copper or tin alone. Bronze lasts longer than copper. Pure copper can be oxidized by air and also by water. When copper is oxidized by air or water, it turns green (the color of "copper oxide"), and falls apart.

When people learned how to make and work iron, the Bronze Age ended, and the Iron Age started. Iron can be made harder than bronze, but is susceptible to corrosion (see rust). Iron also wears away faster than bronze, when different pieces are moving against each other. Iron is very common, and easy to make. For this reason, iron costs less than bronze. This is the reason why iron is now used where bronze used to be used.

Use Today[change | change source]

Bronze is still used to make many parts of machines. We choose to make a part out of bronze when it is important that the part last for a long time around water and air, or that the part not wear away. The main things that are made out of it are pump parts, bearings, bells, electrical components, gears, valves, and other things.

Bronze parts are usually cast in a foundry. After they are cast, bronze parts can also be worked in a lathe or milling machine, or drilled. Bronze is not normally worked with a hammer like iron.

Names[change | change source]

When an alloy is called Bronze, it usually means the alloy of copper and tin. When two words are used to name an alloy, and one of the words is Bronze, this means that the alloy is made mostly from copper. The other word tells us what other metal was combined with copper to make this alloy.

Other bronzes are:

  • Aluminum Bronze
  • Leaded Bronze
  • Silicon Bronze
  • Phosphor Bronze

Bronze should not be confused with Brass which is a different alloy of copper and Zinc.

Pictures[change | change source]