As the name implies, it is the copper with the highest copper content, because the color purple red is also known as red copper, the main component is copper plus silver, the content is 99.7-99.95%; the main impurity elements: phosphorus, bismuth, antimony, arsenic, iron, nickel, lead, tin, sulfur, zinc, oxygen, etc.; it is used for making conductive equipment, high-grade copper alloy and copper base alloy.
According to the composition, Chinese red copper processing materials can be divided into four categories: common red copper (T1, T2, T3, T4), oxygen free copper (TU1, TU2 and high-purity, vacuum oxygen free copper), deoxidized copper (TUP, tumn), special copper (arsenic copper, tellurium copper, silver copper) with a small amount of alloy elements. Copper, whose conductivity and thermal conductivity are second only to silver, is widely used in making conductive and heat conducting equipment. Red copper has good corrosion resistance in the atmosphere, sea water, some non oxidizing acids (hydrochloric acid, dilute sulfuric acid), alkali, salt solution and a variety of organic acids (acetic acid, citric acid), and is used in the chemical industry. In addition, red copper has good weldability and can be processed into various semi-finished products and finished products through cold and thermoplastic processing. In the 1970s, the output of red copper exceeded that of other copper alloys.
If the theoretical value of resistivity of pure copper is made of various materials with a length of 1 meter and a cross-sectional area of 1 square millimeter, and their resistances (called the resistivity of this material) are measured at 20 ℃ and compared, the resistivity of silver is the lowest, followed by that of copper, aluminum, tungsten, iron, manganese copper and nickel chromium alloy.
The resistivity of aluminum conductor is more than 1.5 times that of copper conductor. Its resistivity is p = 0.0294 Ω mm2 / m, and that of copper is p = 0.01851 Ω· mm2 / m. There are some differences in resistivity with temperature.