Why is there such a big difference in price for the same copper wire?

First of all, physically copper is divided into purple copper and brass.

Brass, which is an alloy of copper and zinc, is also known as pure copper and red copper.

1. Appearance: Purple copper has a layer of red cuprous oxide on the surface, so it is often purplish or rosy red, while brass is usually golden yellow.

2. Composition: The main component of brass is copper and the copper content is very high, but brass is mainly composed of copper and zinc, while special brass will also contain other substances.

3. Electrical conductivity: brass and copper both contain copper so they can conduct electricity, but because brass has more other elements and the copper component of copper is better, so the performance of copper conductors is better than brass.

4. Density: brass density in 8.52-8.62, copper density in 8.9-8.95, so the density of purple copper than brass to be larger.

5. Corrosion resistance: brass < bronze

6. Cutting performance: brass > purple copper

7. Price: Copper is more expensive than brass

8. Use: Purple copper is commonly used in the wire and cable industry, while brass is mainly used for valves, water pipes, and radiators, etc.

Therefore, the choice of copper as the raw material of the wire quality to better.

So, what is the pure copper, oxygen-free copper and deoxidized copper advertised by businesses?

Domestic copper processing in accordance with the composition of four categories: ordinary copper (T1, T2, T3, T4), oxygen-free copper (TU1, TU2 and high purity, vacuum oxygen-free copper), deoxidized copper (TUP, TUMn), adding a small amount of alloying elements of special copper (arsenic copper, tellurium copper, silver copper) four categories.

Pure copper, also known as ordinary copper, is usually classified as No. 1 copper (T1), No. 2 copper (T2), No. 3 copper (T3) and No. 4 copper (T4) for industrial use according to the amount of impurities.

As wire and cable require low resistivity, so the copper content must be pure, so the copper content of wire and cable can reach 99% to 99.5%, which means that the quality of wire and cable manufactured with T1 or T2 copper as raw material is better.

Deoxidised copper is the use of phosphorus to remove the oxygen inside the copper, so that the oxygen content is reduced to less than 100ppm, so the electrical conductivity is reduced, but the welding performance is better, so the general hot water pipe will prefer to use deoxidised copper.

Oxygen-free copper is pure copper that does not contain oxygen nor any deoxidiser residues, but in fact oxygen-free copper still contains some impurities. According to the regulations, the oxygen content of oxygen-free copper is no more than 0.003%, the total amount of impurities is no more than 0.05% and the purity of copper is more than 99.95%.

Because oxygen-free copper is superior in all wire diameters in terms of pullability, oxygen-free copper is better in terms of thermal conductivity and hot and cold processing properties. Oxygen-free copper is also favoured by electronic material specialists because of its excellent plasticity and ductility, its excellent cold working properties and its non-magnetic nature.

Copper and its alloys are now widely used in the electronics industry, and in vacuum electronics, oxygen-free copper is already one of the top seven structural materials used in this field.

Because of the high quality of raw materials required to manufacture oxygen-free copper, the price of oxygen-free copper has always been relatively high on the market, which is why there is such a huge price difference for the same copper wire. In the civilian home improvement line market using oxygen-free copper wire is generally positioned quite high-end products, such as Italy's Prysmian, the United States of America's General Cable, France's Nexans many times expensive, often because the cost is there.

In summary, it can be seen that the wire with copper mainly in brass and purple copper, as well as ordinary purple copper and oxygen-free copper, the better the quality and performance of copper, the higher the price, so that the market will be a variety of prices varying wire.