In high-end manufacturing fields such as electronics, power, new energy, and precision machinery, copper has become an indispensable basic material due to its excellent electrical conductivity (second only to silver), superior thermal conductivity, and good ductility and corrosion resistance. As industrial products continue to develop towards miniaturization, high integration, and high reliability, unprecedented demands are being placed on the precision, efficiency, and consistency of the Copper Stamping process. As a highly efficient and scalable metal forming technology, copper stamping not only determines the geometric accuracy of parts but also directly affects the electrical performance and service life of end products.
Material Selection: The Starting Point for Performance and Process
In industrial contexts, "pure copper" typically refers to high-purity copper (such as grades T1, T2, and T3). Among these, T2 (Cu+Ag≥99.90%) is the mainstream choice for Electrical Copper Stamping Parts due to its balance between cost and performance. Higher grades generally have lower impurity (such as Fe, Pb, and S) content, resulting in better conductivity (up to 97% IACS) and ductility, making them suitable for high-frequency signal transmission or high-current applications, such as relay springs and battery connectors.
It's important to note that while brass (copper-zinc alloy) and bronze (copper-tin alloy) are also "copper alloys," their conductivity is significantly lower than that of pure copper, and they are mostly used for structural components rather than core conductive parts. Therefore, before initiating a Custom Copper Stamping project, the material system must be clearly defined based on functional requirements-whether it's pure copper for ultimate conductivity or an alloy that balances strength and cost.
Furthermore, the form of the raw material (strip, sheet, or bar) and its dimensional tolerances (thickness typically 0.1–2.0 mm) directly affect mold design and feeding stability. High-quality (oxidation-free, scratch-free) stamping copper sheets are a prerequisite for ensuring the appearance of stamped parts and their compatibility with subsequent electroplating/welding.
Process Flow: System Control from Blanking to Finished Product
1. Precise Blanking
Laser cutting or high-precision shearing machines are used to cut coils or sheets into the required blanks. For mass production, fixed-width coils are often used directly with automatic feeders to reduce waste and increase material utilization to over 95%.
2. Surface Pretreatment
Copper exposed to air easily forms an oxide film, affecting lubrication and die life. Standard treatments include weak acid cleaning (to remove the oxide layer) and deionized water rinsing. Some high-cleanliness applications also require electropolishing to achieve a mirror-like surface, providing a consistent coefficient of friction for subsequent precision parts such as Copper Stamping Spring Contacts for Electrical Switches.
3. Die Design and Manufacturing
The die is the "soul" of the stamping process. Given the soft and sticky nature of copper, the clearance between the punch and die is typically set to 8%–12% of the material thickness to balance burr control and springback compensation. The mold materials are mostly high-wear-resistant Cr12MoV or high-speed steel, and anti-adhesion ability is improved through TD coating or DLC coating. For complex three-dimensional structures (such as pressing, copper, stamping, and bending connecting parts), multi-station progressive dies are often used, integrating punching, bending, flanging, and rib forming processes in one stroke to achieve a dimensional accuracy of ±0.02 mm.
4. Parametric Stamping Execution
Lubrication Management: Water-based or synthetic stamping oil is used to form an effective oil film to prevent "burring" and built-up edge;
Speed and Pressure Matching: The servo press uses programmable control of the slide curve, reducing speed and increasing pressure in critical forming sections to reduce the risk of cracking;
Temperature Control: During continuous high-speed stamping, the mold temperature rise must be maintained below 50℃ through internal cooling channels to avoid dimensional drift caused by thermal expansion.
5. Comprehensive Quality Inspection
Geometric Dimensions (CMM or optical imaging instrument);
Surface Defects (AOI automatic optical inspection);
Functional Performance (such as contact resistance, elastic force value);
Microstructure (metallographic analysis confirms no microcracks).
Typical Applications and Technical Challenges
Copper-stamped components are widely used in:
Power Electronics: IGBT module terminals, photovoltaic junction box busbars;
Automotive Electrical: Battery Management System (BMS) sampling plates, high-voltage connector springs;
Consumer Electronics: Mobile phone shielding grounding springs, Type-C interface terminals;
Industrial Control: The base structure of Copper Metal Stamping Electrical Silver Contact Parts.
However, copper stamping still faces three major challenges:
High ductility leading to difficult-to-control springback: requiring pre-compensation through CAE simulation and integration of correction stations in the mold;
Strong tendency to stick to the mold: relying on high-performance coatings and lubrication systems;
Wrinkling of thin materials: requiring optimization of blank holder force and draw bead design.
contact us
If you are developing highly conductive connectors or need to optimise your existing Precision Copper Stamping Parts solutions, please feel free to contact us. We will provide you with full-process technical support from DFM review to mass production implementation.
