Copper Product CNC Machining

Characteristics and selection recommendations for different copper materials: 1) Copper (Pure Copper): Best electrical and thermal conductivity, suitable for electrical and cooling components; 2) Brass (Copper-Zinc Alloy): Good strength and wear resistance, excellent machinability, suitable for plumbing and hardware; 3) Bronze (Copper-Tin Alloy): High strength, wear and corrosion resistance, suitable for bearings, gears, and other mechanical parts; 4) Cupronickel (Copper-Nickel Alloy): Excellent corrosion resistance and low-temperature toughness, suitable for marine engineering and precision instruments. Selection requires comprehensive consideration of conductivity, strength, corrosion resistance, and cost.

Copper has a relatively soft texture and can be machined to high precision: Dimensional accuracy can reach ±0.005mm, geometric tolerance can reach 0.01mm/m; Surface roughness can achieve Ra0.02μm (mirror effect) through precision machining and polishing. For general applications, economical machining accuracy is ±0.01mm with surface roughness Ra0.8μm; High-precision applications can achieve ±0.002mm. Surface quality after machining can be further improved through subsequent polishing and electroplating.

Methods to prevent copper oxidation: 1) Use specialized copper cutting fluids during machining to form protective films; 2) Perform timely surface treatments after machining, such as electroplating (nickel, chrome, gold, etc.) to effectively isolate air; 3) For products not requiring conductivity, apply painting or passivation; 4) Use specialized copper protectants to form transparent protective films; 5) Use vacuum packaging or moisture-proof paper for packaging to avoid humid environments; 6) Maintain dry storage environments and avoid contact with corrosive gases. We can provide the most suitable anti-oxidation solution based on your usage environment.

Main reasons for higher copper machining costs: 1) Raw material cost: Copper market price is much higher than ordinary steel; 2) Machining efficiency: Copper is relatively soft and prone to built-up edge during machining, requiring more frequent tool changes and reducing machining efficiency; 3) Tool cost: Copper machining requires higher-grade tools, usually more expensive carbide or diamond tools; 4) Surface treatment: Copper products often require more complex surface treatment processes to prevent oxidation; 5) Quality control: Copper products are mostly used in high-precision applications with stricter testing requirements, increasing quality control costs. However, copper's excellent performance makes it irreplaceable in specific applications.

Main differences in machinability between brass and bronze: 1) Cutting performance: Brass (especially leaded brass) has excellent cutting performance, chips break easily, and surface quality is good; Bronze (such as tin bronze) has greater cutting resistance, chips are tougher, requiring optimized cutting parameters; 2) Surface quality: Brass more easily achieves high surface finish; Bronze may require more polishing after machining; 3) Wear resistance: Bronze is usually more wear-resistant than brass, suitable for wear-resistant parts like bearings; 4) Thermal conductivity: Brass has better thermal conductivity than bronze, more suitable for heat dissipation components; 5) Weldability: Brass has good weldability while bronze is more difficult to weld. We adjust machining processes based on material characteristics to ensure optimal results.

Common surface treatments for copper products: 1) Electroplating: Gold plating (improves conductivity and corrosion resistance), silver plating (best conductivity), nickel plating (improves wear resistance), chrome plating (aesthetic and corrosion resistant); 2) Chemical treatment: Oxidation coloring (achieves different colors), passivation (forms protective film against oxidation); 3) Mechanical treatment: Sandblasting (matte effect), polishing (from standard to mirror polishing); 4) Coating: Painting, powder coating (suitable for decorative and non-precision parts); 5) Immersion plating: Such as tin dipping, zinc dipping, etc., to improve solderability or prevent oxidation; 6) Electrolytic polishing: Achieves extremely high surface finish and corrosion resistance. Selection depends on usage environment, cost, and appearance requirements.