Copper and copper alloy

• Pure Copper (OFC)

  Pure copper refers to the main two elements copperand silver content of 99.5 ~ 99.95% copper, because of the color purple red, also known asredcopper.Its main impurity elements are phosphorus, bismuth, antimony, arsenic, iron, nickel, lead, tin, sulfur, zinc, oxygen, etc. Pure copper density 8.89 g/cm3, melting point 1083℃. Copper is slightly hard, extremely tough, resistant to wear, and has good ductility, good thermal and electrical conductivity. Pure copper has good weldability, can be cold and thermoplastic processing into a variety of semi-finished products and finished products. Copper has good corrosion resistance and are stable in dry air.

  
  

  Oxygen-free copper (OFC) is pure copper that does not contain Oxygen and does not contain any deoxidizer residues. According to the standard provisions, the oxygen content is not more than 0.003%, the total impurity content is not more than 0.05%, the purity of copper is greater than 99.95%.

  
  

  The most valuable property of pure copper is its excellent electrical and thermal conductivity, second only to gold and silver in all the metals, but copper is much cheaper than silver, so it has become the "protagonist" of the electrical and electronic industry. Copper is mostly used in the electrical and electronic industry, accounting for more than half of the total consumption. In addition, copper is also widely used in light industry, machinery manufacturing, construction industry, national defense industry and other fields, second only to aluminum in the consumption of non-ferrous metal materials. In the manufacture of machinery and transport vehicles, pure copper is used to manufacture industrial valves and fittings, instruments, plain bearings, dies, heat exchangers and pumps. In chemical industry, it is widely used in the manufacture of vacuum, still pot, brewing pot and so on. Used in the defense industry to make bullets, shells, gun parts, etc. In the construction industry, used as a variety of pipes, pipe fittings, decorative devices, etc.

• Copper Alloy

  Copper can form alloys with zinc, tin, lead, manganese, cobalt, nickel, aluminum, iron and other metals, and is divided into three main groups.

  
  

  Brass: copper zinc alloy.

  Bronze: copper tin alloy, etc. (Except zinc and nickel, alloy with other elements are called bronze).

  White copper:copper nickel alloy,copper-cobalt-nickel alloy.

• Brass

  Copper alloys with zinc as the main additive element have a beautiful yellow color and are collectively referred to as brass. Brass alloys containing less than 36% zinc consist of solid solution and have good cold working properties. In order to improve the properties of common brass, other elements are often added, such as aluminum, nickel, manganese, tin, silicon, lead, etc. Aluminum can improve the strength, hardness and corrosion resistance of brass, but reduce the plasticity, suitable for Marine condensate pipe and other corrosion resistance parts. Tin can improve the strength of brass and corrosion resistance to sea water, so it is called naval brass, used for ship thermal equipment and propellers. Lead improves the machinability of brass, the free-cutting brass commonly used in watch parts and brass castings used in valves and pipe fittings.

• Bronze

  Copper alloys other than brass and white copper are called bronze, including tin copper, aluminum bronze, beryllium bronze, phosphor bronze, silicon bronze, manganese bronze, zirconium bronze, chromium bronze, cadmium bronze, magnesium bronze, iron bronze, tellurium bronze, etc.

  
  

  Tin bronze has good casting, antifriction and mechanical properties, and is suitable for manufacturing bearings, worm wheels, gears, etc.

  
  

  Lead bronze is a widely used bearing material for modern engines and grinders.

  
  

  Aluminum bronze has high strength, good wear resistance and corrosion resistance, and is used for casting high load gear, shaft sleeve, Marine propeller, etc.

  
  

  Beryllium bronze and phosphorbronze have high elastic limits and good electrical conductivity, and are suitable for the manufacture of precise springs and electric contact elements. Beryllium bronze is also used to make sparkless tools for coal mines, oil depots, etc.

  
  

• White Copper

  White copper is a copper base alloy with nickel as the main additive element. It is silver white and has metallic luster. Copper and nickel can be infinite solid solution to each other, thus forming a continuous solid solution, that is, regardless of the proportion of each other, and alwaysα-single-phase alloy. When nickel is added to pure copper, the resulting alloy becomes as white as silver. The higher the nickel content, the whiter the color. The content of nickel in white copper is generally 25 percent. Meanwhile, manganese, iron, zinc or aluminum can also be added to white copper to become special white copper.

  
  

  The white copper density is 8.9-8.88g /cm3.

  
  

  The addition of nickel to pure copper can significantly improve the strength, corrosion resistance, hardness, resistance and thermoelectricity, and reduce the resistivity temperature coefficient. Therefore, the mechanical and physical properties of white copper are very good, good ductility, high hardness, beautiful color, corrosion resistance, rich deep drawing properties, is widely used in shipbuilding, petrochemical, electrical appliances, meters, medical instruments, daily necessities, handicrafts and other fields, and is an important resistance and thermocouple alloy. But because nickel is a scarce material, it is expensive. Nickel white copper is mainly used in crystal oscillating element shell, crystal shell, sliders for potentiometer, medical machinery, building materials and so on.