The OnlineMetals Guide to Copper
Copper and its alloys were some of the first metallic elements to be discovered by ancient man. Because the purification of copper requires significant amounts of electricity, however, uses were found for its many alloys and variants. The copper metals category can be roughly segregated into three separate groups - Copper alloys, which this page will discuss, as well as Brass and Bronze. The term copper alloy is generally applied where the material in question is primarily made of copper, as opposed to brass, which is a mixture of copper and zinc, or bronze, where the alloy is copper plus (usually) tin and possibly some other element, like aluminum or manganese.
The copper alloys are generally red or pinkish in color. They are known for their malleability and ductility (ease of working), heat conductivity, and electrical conductivity. Copper does develop an oxide layer, or patina, when exposed to water. The most famous example of this is the Statue of Liberty in New York, which is primarily made from copper, but has patinaed over the years due to its exposure to the weather.
In industrial use, it is typically specified where there is a need for either ductility (plumbing or roofing applications) or electrical conductivity (such as for electromagnets, electrical motors, or wave guides). In home/residential/architectural applications, it is typically used primarily for its color (i.e. a kitchen backsplash or cutting board) or its heat transfer properties (i.e. pots and pans).
Pure copper (alloys 101 - 110) are also often known as Electrolytic Tough Pitch or ETP Copper.
OnlineMetals now stocks C101 Oxygen Free Electronic Copper.
This is a 99.99% pure copper with 0.0005% oxygen content. It achieves a minimum 101% IACS conductivity rating, but is generally valued more for its chemical purity than its electrical conductivity. This copper is finished to a final form in a carefully regulated, oxygen-free environment. Silver (Ag) is considered an impurity in the OFE chemical specification. This is also the most expensive of the three grades listed here.
C145 Tellurium Copper is used when the electrical conductivity properties of copper are desired, but machining must take place on the product. C145 is deoxidized using phosphorus, and tellurium is used to improve the machinability to 85% of free-machining brass rod.
OnlineMetals.com currently stocks five alloys of copper in various shapes and sizes.
C101 Oxygen Free Copper
C110 (ETP) Copper
C122 Phosphorus Copper
C145 Tellurium Copper
C147 Sulfur Copper
- Cold Roll
- Hot Roll
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