Hot rolled pure copper plate
Hot-rolled pure copper sheet is produced through a hot-rolling process. It exhibits excellent electrical and thermal conductivity, ductility, and corrosion resistance, making it indispensable in the electronics, aerospace, and chemical industries. Pure copper sheet typically has a purity of over 99.5% , with high-purity products reaching 99.95% . Its electrical conductivity is ≥ 98% IACS and its thermal conductivity is ≥ 380W/(m・K) , making it an ideal electrical and thermal conductor. Compared to cold-rolled pure copper sheet, hot-rolled pure copper sheet has coarser and more uniform grains and better ductility (elongation ≥ 30% ), making it suitable for complex forming processes such as deep drawing and bending. Available in thicknesses of 3-50mm , it can meet diverse application requirements.
The production process of hot-rolled pure copper sheet requires strict control of temperature and rolling parameters to ensure material purity and performance. First, electrolytic copper ingots (99.95% purity) are used as raw material and smelted in a reverberatory furnace or industrial frequency induction furnace at a temperature of 1100-1150°C. A small amount of deoxidizer (such as phosphor copper) is added to remove oxygen and impurities from the melt, ensuring the purity of the copper sheet. The molten copper is then cast into ingots 100-200mm thick. Homogenization annealing (600-700°C) is required to eliminate casting stress and composition segregation. During the hot rolling stage, the ingots are heated to 800-900°C and gradually thinned to the target thickness through multiple hot rolling passes. The reduction per pass is controlled at 20-30%, and the rolling speed is adjusted according to the thickness (1-5m/min) to prevent cracking caused by work hardening. After hot rolling, the copper plate is water quenched, straightened, trimmed, and finally subjected to surface treatment (such as pickling) to remove the oxide scale and ensure a surface finish of Ra ≤ 1.6μm.
In the electronics and electrical sector, hot-rolled pure copper sheet is a core material for conductive components. Transformer windings and leads are made of high-purity hot-rolled pure copper sheet, whose excellent conductivity reduces energy loss. One transformer manufacturer saw a 1.5% increase in product efficiency after adopting 99.95% pure copper sheet. The commutator segments of motors are made of pure copper sheet with a thickness of 5-10mm. Stamping and precision machining ensure good contact with the brushes. Test data from one motor brand shows that commutators using high-quality pure copper sheet have a service life of over 20,000 hours. In printed circuit boards, pure copper sheet serves as the conductive layer, forming the circuit pattern through an etching process. Its high purity ensures stable signal transmission. Using this material in high-density circuit boards at an electronics company has increased signal transmission rates by 10%.
The aerospace and chemical industries have specific requirements for the performance of hot-rolled pure copper sheet. Spacecraft thermal control systems use pure copper sheet as heat sinks. Its excellent thermal conductivity allows it to quickly transfer heat generated by the equipment to space. A certain satellite’s thermal control system uses 0.5mm thick pure copper sheet, increasing heat dissipation efficiency by 20%. Aircraft engine cooling oil pipes are made from thin-walled pure copper sheet (3-5mm thick). This sheet can withstand high-temperature and high-pressure operating environments and has excellent plasticity, making it easy to bend and form. One aircraft engine manufacturer saw a 30% increase in cooling system reliability after adopting this material. In chemical equipment, pure copper sheet is used to make corrosion-resistant pipes and containers, resistant to corrosion from organic acids and alkalis. The reactor lining at a chemical plant uses pure copper sheet, achieving a service life of over five years.
With the development of high-end manufacturing, the performance and production technology of hot-rolled pure copper sheet are constantly improving. Manufacturers have developed ultra-high-purity pure copper sheet (99.99%) for use in lead frames in the semiconductor industry, meeting the high conductivity requirements of chip packaging. To meet complex forming needs, deep-drawing-grade pure copper sheet has been developed, with an elongation of over 40%, suitable for the production of special-shaped conductive components. In terms of process innovation, the integrated continuous casting and hot-rolling technology is being adopted to improve the dimensional accuracy (thickness tolerance ±0.05mm) and surface quality of the copper sheet, increasing material utilization to over 90%. In the future, with the development of industries such as new energy and 5G communications, the demand for high-purity, high-performance hot-rolled pure copper sheet will continue to grow, driving its application in more high-end fields.
