1. Red Copper (T 1, T 2, t 3) red copper is pure industrial copper, because it has a rose red color, the surface of the oxide film formed after the purple, it is generally known as red copper, copper content is 99.5 ~ 99.95% , it is containing certain oxygen copper, therefore also known as oxygen copper, sometimes it can be thought of as a copper alloy. The main grades of ordinary copper are T1, T2 and T3, which are used for making conductive equipment, high grade copper alloy and copper base alloy. 2. Oxygen-free copper (TU0, TUI, TU2) is pure copper that contains neither oxygen nor any deoxidizer residue, but in fact contains very little oxygen and some impurities. The purity of TU1 is 99.97% , the oxygen content is not more than 0.003% , the total impurity content is not more than 0.03% , the purity of TU2 is 99.95% , the oxygen content is not more than 0.005% , the total impurity content is not more than 0.05% . 3. Red Copper/oxygen Free Copper Series No. 01. Foil Strip

6. The difference between copper and Oxygen Free Copper 01. Use Distinction: T1 and T2 are mainly used for conducting, heat conducting and corrosion resistant components, such as conducting wires, cables, conducting screws, shells and various conducting tubes, etc. . T3 is mainly used as a structural material, such as electrical switches, washers, rivets, nozzle and a variety of conduits, also used in some conductive components. (2) use of oxygen-free copper: mainly used in electric vacuum instrument parts, widely used in bus bar, conductive bar, waveguide, coaxial cable, vacuum seal, vacuum tube, transistor parts, etc. . Quality Characteristics Difference (1) quality characteristics of Red Copper: at 20 °C, the density of 99.999% processed pure copper is 8958 kg/m3, and the density of as-cast electrolytic fine copper is 8300ー8700 kg/m3(the average value is 8500 KG/M3) , the density of as-cast gasses free electrolytic copper is 8850ー8930kg/m3(the average value is 8920kg/m3) , the density of C11000 and C12500 is 8890kg/m3. (2) the quality characteristics of oxygen-free copper: oxygen-free copper at 20 °c, the shrinkage of solidification is 4.92% , the density is 8.94 g/cm3. Magnetic Distinction (1) the magnetic properties of Red Copper: Red Copper is a diamagnetic material, the room temperature magnetic susceptibility is-0.08510-6, the temperature has little influence on its magnetic susceptibility. Ferromagnetic impurity (especially iron) if it is insoluble in copper, it makes copper appear ferromagnetic. (1) magnetic properties of oxygen-free Copper: oxygen-free copper is diamagnetic, the room temperature susceptibility is-0.08510-6. Kill. Processing Properties Copper 1. Smelting and casting process performance: using reverberatory furnace melting or industrial frequency core induction furnace melting; using copper mold or iron mold casting, melting process should minimize gas sources, and the use of burnt charcoal as flux, phosphorus can also be used as a deoxidizer. It is suggested that the casting temperature should be 1150-1230 °C and the linear shrinkage should be 2.1% . 2. MOLDING PROCESS PERFORMANCE: excellent cold, Hot processing performance, can use a variety of traditional processing technology, such as drawing, calendering, deep drawing, bending, precision and spinning. Should control the heating medium atmosphere, so that micro-oxidation. The hot working temperature is 800-950 °C. 3. WELDING PROCESS PERFORMANCE: easy to solder, brazing, also can Gas metal arc welding, flash welding, electron beam welding and gas welding, but not suitable for contact point butt welding and submerged arc welding. 4. Machinability and grindability: The machinability of red copper is 20% . Oxygen-free Copper 1. SMELTING AND CASTING PROCESS PERFORMANCE: oxygen-free copper is mainly used power frequency core induction furnace smelting. In order to ensure the quality of oxygen-free copper, it is necessary to achieve "fine material seal" , that is, the raw material of electrolytic copper containing w (Cu) > 99.97% and w (Zn) < 0.003% , pay attention to reducing the source of gas when melting, and cover it with calcined charcoal, trace amounts of phosphorus may also be added as a deoxidizer. The ingots are cast in a semi-continuous casting process protected by nitrogen or covered with soot. The casting temperature is 1150-1180 °C. 2. MOLDING PROCESS PERFORMANCE: oxygen-free copper cold and Hot working performance is excellent, can stretch, calendering, extrusion, bending, stamping, shearing, spinning, upsetting, rotary forging, forging, thread pressing, knurling, winding, excellent forgeability of 65% of the forged brass. The hot working temperature is 800-900 °C. 3. WELDING PROCESS PERFORMANCE: Easy to carry out fusion welding, soft brazing, brazing, gas shielded tungsten arc welding, gas shielded metal arc welding, its oxygen fuel gas welding performance is good, do not recommend shielded metal arc welding and most resistance welding methods. 4. Machinability and grindability: The machinability of oxygen-free copper is 20% of that of free-cutting brass HPb63-3. 8. Oxygen-free copper smelting strict distinction, oxygen-free copper should be divided into ordinary oxygen-free copper and high-purity oxygen-free copper. The common oxygen-free copper can be smelted in the power frequency induction furnace with iron core, while the high purity oxygen-free copper should be smelted in the vacuum induction furnace. When semi-continuous casting is used, the refining process of melt in melting furnace and holding furnace is not restricted by time. The quality of copper liquid not only depends on the refining quality of melting furnace and holding furnace, but also depends on the stability of the whole system and process. In order not to pollute the melt, oxygen-free copper is smelted and refined without any additives, the surface of melting pool is covered with charcoal, and the reducing atmosphere is the common melting atmosphere. The induction furnace for smelting oxygen-free copper in induction furnace should have good sealing property. High Quality Cathode copper should be used as raw material to smelt oxygen-free copper. High Purity Cathode copper should be used as raw material for smelting high purity oxygen-free copper. If the cathode copper is dried and preheated before entering the furnace, the moisture or moist air that may be adsorbed on the surface can be removed. When oxygen-free copper is smelted, the thickness of the charcoal layer on the surface of the molten pool in the furnace should be twice as thick as when ordinary pure copper is smelted, and the charcoal needs to be renewed in time. Although charcoal mulching has many advantages, such as heat preservation, air insulation and reduction, it also has some disadvantages. For example, charcoal easy to absorb moisture in the air, or even directly absorb water, which makes it possible to make large amounts of hydrogen absorption copper channels. Charcoal or carbon monoxide can reduce Cuprous oxide, but not hydrogen. Therefore, the charcoal should be carefully selected and calcined before being added to the furnace. In the process of melting, pouring, heat preservation and whole casting, it is necessary to protect the melt completely for oxygen free copper production. Many modern oxygen-free copper smelting and casting production lines, not only smelting, including the charge of drying preheating, transfer chute, pouring chamber and so on have taken comprehensive protection. Modern large-scale oxygen-free copper production lines, some are to producer gas as a protective gas, and gas producer is mostly natural gas as raw material. A method of producing a protective gas commonly used abroad is: First, natural gas with relatively low sulfur content and 94% ~ 96% methane are burned in air of theoretical value, and nickel oxide is used as the medium to remove hydrogen, the resulting gas consists mainly of nitrogen and carbonic acid gas. Then, the carbonated gas is changed into carbon monoxide by hot charcoal, and the oxygen-free gas containing 20% ~ 30% carbon monoxide and the rest is nitrogen is obtained. In addition to producer gas, other gases such as nitrogen, carbon monoxide or argon are used as media for oxygen-free copper melt protection or refining. Vacuum smelting is the best choice for smelting high quality oxygen-free copper. Vacuum melting can not only greatly reduce the content of oxygen, but also the content of hydrogen and some other impurity elements. Graphite crucible and high purity cathode copper or remelting copper, which have been refined twice, are usually used as raw materials in vacuum medium frequency coreless induction furnace. Also included in the furnace with the cathode copper is a flake-like graphite powder for deoxidation. In fact, deoxidation is mainly carried out by carbon in graphite crucibles. Carbon consumption can be calculated as 100g of carbon per kg of copper, for example. Experience shows that the higher the oxygen content in the liquid copper at the beginning, the faster the deoxidation reaction is carried out at the initial stage of smelting. The oxygen content of oxygen-free copper obtained by vacuum melting can be less than 0.0005% , even less than 0.0001% ~ 0.0003% . In fact, only copper smelted and cast in a certain degree of vacuum can be made into castings completely free of oxygen and other gases. Therefore, the vacuum of the vacuum furnace used to produce copper for electronic tubes should be above 10-6. 9. Introduction to other copper

Source: yueting special alloy