First, what is lead-free copper?
Lead-free copper refers to copper alloys or pure copper materials whose lead content is strictly controlled to meet specific safety standards.
Lead-free copper is not the same as red copper. Red copper is industrially pure copper, with a copper content of 99.5%-99.95% and a purple-red appearance. Lead-free copper can be an alloy material derived from copper alloys such as brass by controlling the lead content, or it can be pure copper that has undergone special treatment to achieve lead-free standards. However, lead-free copper differs from red copper in composition, properties, and uses.
The lead content requirements for lead-free copper vary depending on the application and standard. For example, in some electronics and automotive parts, the RoHS standard requires a lead content of less than 0.1% (with the exception of copper alloys, which require a lead content of less than 4%).
The US electronics industry requires a lead content of less than 0.01%.
The main characteristics of lead-free copper are good workability, high strength, and safety and environmental protection.
So, how is lead-free copper manufactured?
Step 1: Material selection. Select qualified raw materials, such as high-purity electrolytic copper, zinc, and other additive elements (such as bismuth, silicon, magnesium, antimony, selenium, and tellurium, depending on the specific composition requirements of the lead-free copper).
Step 2: Smelting. The electrolytic copper is heated to a high temperature (generally 1100-1200°C) to melt it into a liquid state.
Step 3: Adding Elements. Zinc and other lead-substituting elements are added to the molten copper according to the designed alloy composition ratio and stirred thoroughly to ensure a uniform mixture.
Step 4: Refining. Refining agents are added to remove impurities and gases, improving the purity and quality of the copper alloy. Refining agents typically include fluorite, cryolite, borax, silicon dioxide, copper oxide, sodium fluorosilicate, and titanium dioxide.
Step 5: Casting. The refined copper alloy is cast at an appropriate temperature (e.g., 1000-1050°C followed by heating to 1150-1200°C) to produce lead-free copper ingots. Finally, subsequent processing takes place. Depending on product requirements, the ingots undergo forging, extrusion, rolling, and stretching processes to produce lead-free copper products in various shapes and specifications, such as rods, tubes, plates, and wire.
So, what are the main applications for lead-free copper?
Electronic and electrical appliances: It is widely used in the manufacture of electronic and electrical connectors, plug-ins, wire and cable, switchgear, and other components, as lead-free copper meets the electronics industry's environmental requirements and has excellent conductivity and machinability.
Bathroom fixtures: It is used in the manufacture of faucets, valves, and bathroom hardware, meeting the corrosion resistance and safety requirements of bathroom fixtures.
Medical equipment: It can be used to manufacture medical device components, such as surgical instruments, dental instruments, and medical device connectors. Its safety and biocompatibility are crucial for medical applications.
Mechanical manufacturing: In mechanical engineering, lead-free copper is used to manufacture various mechanical parts, connectors, and fasteners, such as screws, nuts, bearings, and gears.
The company has a cluster of leading copper processing production lines in China, including:
German imported precision copper tube production line (annual output of 30,000 tons)
Japanese technology copper foil rolling line (thinnest up to 6μm)
Fully automatic copper bar continuous extrusion line
Intelligent copper sheet and strip finishing mill unit
Digitalized control and management of the whole production process is realized through MES system, and the dimensional accuracy of the products can reach ±0.01mm.
