Features of Copper
Copper: A Testament to Durability
While most metals corrode and break down with the passage of time, copper is highly corrosion-resistant. The strength of copper can be clearly witnessed in comparison to steel. In an experiment undertaken to learn the durability of cooper versus steel, a 1mm thick plate of both metals were placed in water. The results showed it would take 197 years for copper to corrode while the steel plate developed a hole after six years.
Other examples of copper's durability include:
- It is said that there are remnants of a water supply pipe made of copper, still intact today. That was originally used in the temples of Apsil in ancient Egypt — some 5,000 years ago.
- A 33.4 cm-long copper sword from the Bronze age, now in the custody of the National Museum of Korea, was excavated in the areas of Songguk-ri, Chochon-myeon, Buyeo-gun, south of the Chungcheong province. A Honyeong-style 33.3 cm-long copper sword, now in the custody of the Gyeongju National Museum, was also excavated in Jindong-ri, Jindong-myeon, Uichang-gun, south of the Gyeongsang province. Both swords were known to be manufactured in the 4th or 5th century B.C.
- Copper is a metal that forms a thin film the moment it comes into contact with moisture or water, in order to protect its own surface. A U.S. study revealed that the phosphorus deoxidized copper plates used in a 20-year-old house as roofing material would resist corrosion up to 1,300 years.
Malleability of Copper
Of all the metal in the world, next to gold and silver, copper can be forged the broadest, thinnest, and longest. Copper plates, 0.03mm thinner than paper, are used in circuit boards of a wide range of electronic goods. Because of the superb ductility of copper, it is used as a material for ammunition cartridge cases and cannonballs. Copper can also be welded into all kinds of metals except aluminum. Copper is the best material for making cast products. Statues, faucets or other types of valves, door locks and other common, daily goods are made of this remarkable metal.
Copper is generally divided into pure copper and copper alloy. Pure copper is commercialized and used as a material to make copper alloy. Copper alloys, meanwhile, are produced for special purposes since their mechanical and physical properties can be controlled.
The materials used in aircraft or rockets are required to be lightweight, but heat-resistant. In such cases, the metals with the properties that best meet the requirements are used. If such materials cannot be found, however, a new alloy must be developed. In fact, it is possible to produce an alloy that mixes the best properties from all metals.
Metals, by nature, can conduct electricity and heat. At zero degrees Fahrenheit, silver has the greatest conductivity, but silver's cost makes it an impractical metal for widespread use. Copper, meanwhile, has the second greatest conductivity, thus being used widely where good conductivity is required.
Thermal conductivity generally based on the amount of heat required to raise the unit weight body temperature by one degree. Copper has great thermal conductivity, nine times that of steel and 24 times better than stainless steel. Therefore, it is the most suitable material when manufacturing heating pipes, pipes for boilers, or heat exchanges.