How to choose suitable copper sheet processing technology?

The selection of suitable copper sheet processing technology needs to comprehensively consider factors such as material characteristics, processing requirements, accuracy requirements and cost. The following are key decision dimensions and practical suggestions:

First, the core influencing factors

1. Material characteristics

Copper alloy type

Common processing difficulties of hardness/ductility of typical grades of alloy types

Pure copper T2, TU1 soft/high-ductility easy-sticking knives need to be scratch-proof.

Brass H62 and H65 are easy to produce chips during medium hard/medium extended cutting, which needs chip breaking treatment.

Bronze QSN 6.5-0.1 is easy to crack in hard/low ductility forming and needs preheating.

State: Annealed state (soft) is suitable for complex forming, hard state is suitable for rigid structural parts, and semi-hard state gives consideration to both forming and strength.

2. Processing objectives

Shape: simple geometric figures (such as rectangle and round hole) can be stamped; Complex curve/hollowing priority laser cutting or wire cutting.

Accuracy:

Precision parts (tolerance 0.01mm): CNC milling, wire cut wire cutting and precision stamping.

General parts (tolerance ±0.1mm): common stamping and shearing machine cutting.

Surface quality: electrolytic polishing is required for mirror surface; Anti-oxidation selective electroplating or passivation.

Second, the process matching guide

1. Select the cutting process according to the thickness.

Comparison of recommended process cost and efficiency in thickness range

≤ 0.5 mm laser cutting, precision stamping, high medium (laser)/high (stamping)

0.5-3 mm CNC stamping and CNC milling medium high (stamping)/medium (milling)

> 3 mm shearing machine cutting, plasma cutting low height.

2. Select the molding process by batch.

Small batch (< 100 pieces):

Laser cutting (die-free)+manual bending is suitable for sample development.

Case: Customized electronic component connection board.

Large batch (> 10000 pieces):

Stamping die+automatic production line, reducing the cost of a single piece.

Case: automotive wiring harness terminal (brass H65, the annual demand is millions).

3. Select surface treatment according to functional requirements.

Typical application scenarios of functional requirements recommendation process

High-frequency electronic component with high conductivity silver plating (thickness 0.1-0.3 μ m)

High wear resistance hard chromium plated sliding contact (thickness 5-10μ m)

Anti-fingerprint/decorative nano-coating+brushed consumer electronics shell (such as mobile phone middle frame)

Oxidation-resistant chromium-free passivation (environmental protection) outdoor building copper plate

Third, the cost and efficiency balance strategy

1. Avoid excessive processing

For example, if the copper sheet only needs to be roughly cut (such as the blank of structural parts), the cost can be reduced by more than 50% by using the shearing machine instead of laser cutting.

Tip: Communicate with the designer to make clear whether the tolerance of drawings is necessary (if ±0.05mm is relaxed to ±0.1mm, a lower-cost process can be adopted).

2. Optimization of combined process

Case: Complex copper fittings

Stamping main structure (low cost batch);

Laser cutting local fine holes (to make up for the limitation of stamping die);

Vibration grinding deburring (instead of manual grinding, the efficiency is increased by 80%).

3. Equipment compatibility considerations

If the existing equipment is a CNC punch, give priority to the development of stamping process; If outsourcing high-precision machining (such as micron-sized holes) is needed, choose a supplier with wire cut equipment.

Fourth, the main points of risk avoidance

Material rebound control:

The rebound angle of hard copper sheet is large when bending (for example, H68 brass has a rebound angle of about 5), so the compensation angle needs to be reserved in the mold.

Prevention of thermal deformation:

Laser cutting thick copper sheet (> 5 mm) is prone to thermal deformation, so pulsed laser or water cooling can be used for assistance.

Surface damage protection:

The surface of pure copper is easy to scratch, so it is necessary to pad PE film or use nylon fixture (especially mirror parts) during processing.