Copper is a ductile and malleable base metal that is valued for its high thermal and electrical conductivity.
Easily identifiable because of its iridescent, golden red color, copper and its alloys, have been used by humans for thousands of years.
Due to its effectiveness as an electrical conductor, copper is now most often found in related applications, including in the wiring for our homes and offices, and in the circuitry, connectors and components that make virtually all electronic devices function.
Copper is typically extracted from oxide and sulfide ores that contain between 0.5 and 2.0 percent copper.
The refining techniques employed by copper producers depend on the ore type, as well as other economic and environmental factors. Currently, about 80 percent of global copper production is extracted from sulfide sources.
Regardless of the ore type, mined copper ore must first be concentrated to remove gangue, unwanted materials embedded in the ore. The first step in this process is crushing and powderizing ore in a ball or rod mill.
From common household electrical wiring to boat propellers and from photovoltaic cells to saxophones, copper and its alloys are employed in a myriad of end-uses.
The percentage of global copper production consumed by each sector is estimated by the CDA to be:
Aside from silver, copper is the most effective conductor of electricity. This, combined with its corrosion resistance, ductility, malleability and ability to work within a wide range of power networks, makes the metal ideal for electrical wiring.
Virtually all electrical wiring, save for over-head power lines (which are made from more lightweight aluminum), are formed with copper.
Busbars, conductors that distribute power, transformers and motor windings are also all dependent upon copper's conductivity. Owing to its effectiveness as a conductor of electricity, copper transformers can be up to 99.75 percent efficient.
Electrical applications, including computer technology, televisions, mobile phones and portable electronic devices, have in recent decades become a major consumer of copper. Within these devices, copper is vital to the production of:
Another industry that is heavily reliant on the element is telecommunications. Finely twisted copper wires are used in ADSL and HDSL wiring for local area network (LAN) internet lines. Unshielded twisted pair (UTP) lines contain eight color-coded conductors, which are constructed of four pairs of thin copper wires. And despite the increase in wireless technology, interface devices such as modems and routers remain dependent on copper.
The renewable energy sector has also benefitted from copper's conductive properties. The base metal is used in the production of both copper-indium-gallium-selenide (CIGS) photovoltaic cells and wind turbines. A single wind turbine, for example, can contain up to 1 metric tonne (MT) of the metal. Besides the production of electricity, copper is also integral to the motors and distribution systems associated with alternative energy technology.
Copper tubing is now the standard material for potable water and heating systems in most developed countries. This is in part due to its bacteriostatic properties, or in other words copper's ability to inhibit the growth of bacterial and viral organisms in water.
Other benefits of copper as a tubing material include its malleability and solderability - it can be easily bent and assembled - as well as its resistance to extreme heat corrosion.
Copper and its alloys are considered stable and corrosion resistant, which make them ideal for not only transporting potable water, but also for use in saltwater and industrial environments. Some examples of such applications include in:
For hundreds of years, copper has also been used as an architectural metal. Some of the oldest examples of copper's use as an aesthetic, structural metal include the doors of the Precinct of Amun Re at Karnak, in Egypt, which dates back 3000-4000 years, and the copper shingle roof atop Sri Lanka's 162 foot tall Loha Maha Paya temple, constructed in the third century B.C.
Pure copper adorns the domes and spires of many medieval churches and cathedrals, and in more modern times has been used on government buildings, such as the Canada's parliament buildings, and private residences, including many designed by Frank Lloyd-Wright.
One reason for the wide-use of copper as a construction material is its natural formation of a visually appealing green tarnish - known as patina - that results from the weathering and oxidization of copper. Aside from its aesthetically pleasing appearance, architects and designers prefer the metal because it is lightweight, durable, corrosion resistant and easy to join.
Copper decorative and architectural hardware, however, is not limited to external applications. Interior designers often use the metal and its alloys, brass and bronze, for fixtures such as:
Hospitals and medical facilities, in particular, value copper for its bacteriostatic properties, which has resulted in its growing use as a component of interior fixtures, such as faucets and door handles, in medical buildings.
Core components of planes, trains, automobiles and boats are all dependent on the electrical and thermal properties of copper.
In automobiles, copper and brass radiators and oil coolers have been the industry standard since the 1970s.
More recently, the growing use of electronic components, including on-board navigation systems, anti-lock breaking systems and heated seats, has continued to increase demand for the metal from this sector.
Other copper containing car components include:
Growing demand for hybrid and electric cars will further increase global copper consumption. On average, electric cars contain roughly 55lbs (25kgs) of copper.
Metal foils and copper chemicals are incorporated into both nickel-metal hydride and lithium-ion batteries that power fuel-efficient vehicles, while cast copper rotors have been used as an alternative to rare earth magnet motors.
High-speed trains can use up to 10MT of copper per kilometer of track, whereas powerful locomotives contain as much as 8MT of the base metal.
Overhead contact wires for trams and trolleys like those used in San Francisco and Vienna are made using copper-silver or copper-cadmium alloys.
Two percent of an airliner's weight can be attributed to copper, which includes as much as 118 miles (190km) of wiring.
Because of their excellent resistance to salt water corrosion manganese- and nickel-aluminum bronzes are used to cast boat propellers that can weigh up to several tons. Ship components, including pipes, fittings, pumps and valves, are also made with similar alloys.
Copper alloys are metal alloys that have copper as their principal component. They have high resistance against corrosion. The best known traditional types are bronze, where tin is a significant addition, and brass, using zinc instead.
High Strength Copper – Beryllium Alloys
Beryllium additions, up to about 2 wt%, produce dramatic effects in several base metals. In copper and nickel, this alloying addition promotes strengthening through precipitation hardening. In aluminum alloys, a small addition improves oxidation resistance, castability and workability. Other advantages are produced in magnesium, gold, zinc, and other base metals.