Human beings have been working with copper for longer than 10,000 years. Archeologists identified a copper pendant in what is now northern Iraq that dates back to 8700 B.C. In contrast, the earliest gold jewelry that’s been discovered only dates back to 4000 B.C. Wrought copper alloys continue to play an important role in many industrial applications that are essential to modern life.
What Are Copper Alloys?
When copper is the principal ingredient in combination of metals, the resulting blend is referred to as a “copper alloy.” The two best-known copper alloys are probably bronze and brass.
Bronze is an alloy that primarily consists of copper and tin. Occasionally, other metals such as nickel, zinc or aluminum may be added to the mix to improve the alloy’s hardness, ductility or resistance to corrosion. Bronze was such a popular material between approximately 3000 B.C. and 1000 B.C. that one of the nicknames for that period is the Bronze Age.
Brass is an alloy made of copper and zinc. It’s highly prized among manufacturers of decorative items because its color and shine are highly reminiscent of gold. In addition to its ornamental uses, brass is frequently used in plumbing and electrical applications.
Other Copper Alloys
A variety of other copper alloys are available as well:
• Gunmetal: In the Middle Ages, cannons were manufactured out of copper alloyed with tin, zinc and lead. This particular mixture has come to be known as “gunmetal.”
• Copper-nickel alloys: Copper-nickel alloys are highly resistant to saltwater corrosion. In consequence, they’re widely used in marine applications.
• Copper-nickel-zinc alloys: Copper-nickel-zinc alloys shine with a lovely silvery color and are often used as substitutes for silver in flatware, in jewelry and in the manufacture of certain musical instruments like flutes.
• Copper-beryllium: The hardest copper alloy is the one formed by mixing copper with beryllium. This alloy has a tensile strength that’s comparable to stainless steel, but it has better resistance to corrosion than steel, and higher electrical and thermal conductivity. It’s used for manufacturing tools in the mining and petrochemical industries.