Electrical round aluminum wire
Electrical round aluminum wire is a round wire made from pure aluminum or aluminum alloys through a drawn process. It is widely used in electrical equipment such as wires and cables, motor windings, and transformer coils, serving as a crucial foundation for power transmission and conversion. Its diameter typically ranges from 0.5 to 10 mm, with varying specifications available to meet diverse conductivity requirements. Pure aluminum grades such as 1060 and 1350 are commonly used. 1350 aluminum wire boasts an aluminum content exceeding 99.5%, resulting in exceptional conductivity and suitability for applications requiring high efficiency. Some aluminum alloy round aluminum wires incorporate small amounts of elements such as magnesium and silicon to enhance strength while maintaining a certain level of conductivity, making them suitable for more complex working environments.
The production process for electrical round aluminum wire involves key steps, including smelting and casting, hot rolling, cold drawing, and annealing. First, the aluminum ingots are heated to 700-750°C in a smelting furnace to melt. Refining agents are added to remove hydrogen and non-metallic inclusions from the melt, ensuring the purity of the molten aluminum. The molten aluminum is then cast into round ingots with a diameter of 80-120 mm. After heating the ingots to 400-500°C, they are hot rolled into aluminum rods with a diameter of 10-20 mm. During the hot rolling process, the rolling speed and reduction are controlled to achieve a uniform microstructure and a smooth surface. Cold drawing is the core process that determines the dimensional accuracy of the round aluminum wire. The hot-rolled aluminum rods are drawn through multiple drawing dies, with a reduction rate of 10%-20% per pass, gradually reaching the target diameter. Emulsion lubrication and cooling are used to prevent scratches on the wire surface and maintain a diameter tolerance of ±0.02 mm. Round aluminum wires that need to be bent and wound need to be annealed. They must be heated to 300-400°C under inert gas protection, kept warm for 1-3 hours, and then slowly cooled to reduce the hardness of the material, improve the plasticity, and achieve an elongation of more than 20% to meet subsequent processing requirements.
The performance characteristics of electrical round aluminum wire give it significant advantages in the electrical field. First, it is lightweight and low-cost. Aluminum’s density is only about one-third that of copper. With comparable electrical conductivity, it weighs far less than copper wire, significantly reducing equipment load and transportation costs. Furthermore, aluminum’s raw material price is only about one-quarter that of copper, significantly reducing the manufacturing cost of electrical products. This is particularly advantageous in large-scale projects such as high-voltage cables and overhead conductors. Second, it offers excellent electrical conductivity. The conductivity of 1350 pure aluminum round wire can reach over 61% IACS. While lower than copper, this difference can be compensated by increasing the wire diameter, meeting the demands of medium and low voltage power transmission. Third, it offers strong corrosion resistance. Aluminum easily forms a dense oxide film on its surface, effectively resisting corrosion from air and freshwater environments, ensuring long-term stable operation in dry or lightly polluted environments. Fourth, it offers excellent processability. Annealed round aluminum wire exhibits excellent flexibility, allowing for easy bending and winding, making it easy to fabricate windings and coils of various shapes.
Across various application scenarios, electrical round aluminum wire is used in a variety of fields, including power, communications, and construction. In the power transmission sector, high-voltage overhead transmission lines often utilize steel-core aluminum stranded wire, with the aluminum strands being twisted together from electrical round aluminum wire. This leverages aluminum’s lightness and conductivity to enable long-distance power transmission. For example, 110kV high-voltage lines often use 1350 round aluminum wire with a diameter of 2.5-4 mm. In the wire and cable industry, round aluminum wire is often used for the conductive cores of medium and low-voltage cables. The multi-strand twisting enhances flexibility, making it suitable for building wiring and equipment connections . In motor manufacturing, enameled round aluminum wire can be used for the stator windings of small and medium-sized asynchronous motors, reducing motor costs. This is particularly common in light-load equipment such as fans and water pumps. In the transformer sector, some distribution transformers use round aluminum wire for their low-voltage coils, achieving performance while controlling costs through optimized design. With the development of the new energy industry, the use of electrical round aluminum wire in photovoltaic cables, wind power cables, and other applications is also increasing.
Industry trends indicate that electrical round aluminum wire is moving toward high conductivity, high strength, and a thinner diameter. Through the development of new high-purity aluminum materials, such as ultra-high-purity aluminum round wire with a purity exceeding 99.9%, electrical conductivity has been raised to over 63% IACS, narrowing the performance gap with copper wire. Furthermore, aluminum-magnesium-silicon alloy round wire has been developed, maintaining high conductivity while increasing tensile strength to over 200 MPa, making it suitable for challenging environments such as vibration and tension. Continuous breakthroughs in fine-diameter round aluminum wire production technology have enabled the stable production of wire diameters under 0.5 mm, meeting the winding requirements of micromotors and precision instruments. Furthermore, environmentally friendly production practices are driving the industry to adopt green processes such as chromium-free passivation and water-based lubricants to reduce pollutant emissions during production and increase aluminum recycling rates. In the future, with the continued development of the power industry and the increasing demand for cost control, the use of electrical round aluminum wire in medium and low voltage electrical equipment is expected to further increase, driving greater breakthroughs in material research and development and process innovation.
