Copper C330 (Leaded Copper)

Copper C330 (Leaded Copper) is an alloy with high machinability, ideal for applications requiring precision electrical and mechanical parts.

Introduction to Copper C330 (Leaded Copper)

Copper C330, also known as Leaded Copper, is a highly machinable alloy that incorporates small amounts of lead to improve its machinability and surface finish. This alloy combines excellent electrical conductivity with enhanced ease of machining, making it ideal for manufacturing components requiring intricate details and high production rates. Copper C330 is commonly used in CNC machining services to produce high-precision components.

Due to its machinability, Copper C330 is used in automotive, electrical, and industrial equipment industries. CNC machined Copper C330 parts are ideal for applications such as electrical connectors, switches, and mechanical components, where both strength and ease of machining are essential.

Chemical, Physical, and Mechanical Properties of Copper C330 (Leaded Copper)

Chemical Composition (Typical)

Element	Composition Range (wt.%)	Key Role
Copper (Cu)	97.5%	Provides excellent electrical and thermal conductivity
Lead (Pb)	1.5–2.5%	Improves machinability and surface finish
Other Elements	≤0.5%	Residual elements with minimal impact on properties

Physical Properties

Property	Value (Typical)	Test Standard/Condition
Density	8.92 g/cm³	ASTM B311
Melting Point	1,083°C	ASTM E29
Thermal Conductivity	220 W/m·K at 20°C	ASTM E1952
Electrical Conductivity	50% IACS at 20°C	ASTM B193
Coefficient of Expansion	17.5 µm/m·°C	ASTM E228
Specific Heat Capacity	380 J/kg·K	ASTM E1269
Elastic Modulus	110 GPa	ASTM E111

Mechanical Properties (Annealed Temper)

Property	Value (Typical)	Test Standard
Tensile Strength	240–380 MPa	ASTM E8/E8M
Yield Strength (0.2%)	210–350 MPa	ASTM E8/E8M
Elongation	20–30%	ASTM E8/E8M
Hardness	60–80 HB	ASTM E10
Fatigue Strength	~150 MPa	ASTM E466
Impact Resistance	Good	ASTM E23

Note: These values are typical for annealed Copper C330 and can vary based on specific processing conditions.

Key Characteristics of Copper C330 (Leaded Copper)

Excellent Machinability

Copper C330 is specifically designed for easy machining, allowing for high-speed operations with a smooth surface finish, making it suitable for mass production.

Moderate Electrical Conductivity

With 50% IACS conductivity, Copper C330 is suitable for electrical applications requiring moderate conductivity and high machinability.

Increased Strength and Durability

The alloy provides a balance of strength and durability, making it suitable for mechanical parts and connectors in industrial environments.

Good Corrosion Resistance

Copper C330 resists corrosion in most industrial environments, making it ideal for use in parts exposed to moisture and mild acids.

Cost-Effective for High-Volume Production

The ease of machining and durability make Copper C330 an economical choice for large-scale electrical connectors, fittings, and mechanical parts manufacturing.

CNC Machining Challenges and Solutions for Copper C330 (Leaded Copper)

Machining Challenges

Lead Contamination

Lead in Copper C330 can sometimes create chips that contaminate other materials or equipment.

Solution: Proper chip management systems such as vacuum suction or filtration can prevent contamination.

Tool Wear

Lead content can reduce the life of tools if not managed properly due to sticky lead deposits.

Solution: Use carbide or coated tools with lubricants designed for machining leaded alloys to minimize wear.

Chip Formation

Leaded copper alloys often produce long, stringy chips, interrupting machining.

Solution: Use chip breakers and maintain proper coolant flow to control chip formation.

Optimized Machining Strategies

Tool Selection

Parameter	Recommendation	Rationale
Tool Material	Carbide tools with TiN coating	Provides better tool life and reduces wear
Geometry	Positive rake, sharp edges	Improves chip flow and minimizes material buildup
Cutting Speed	100–180 m/min	Prevents excessive heating and enhances tool longevity
Feed Rate	0.08–0.12 mm/rev	Helps to maintain surface finish and dimensional accuracy
Coolant	Flood coolant or air blast	Reduces heat buildup and assists with chip removal

Copper C330 Cutting Parameters (ISO 513 Compliance)

Operation	Speed (m/min)	Feed (mm/rev)	Depth of Cut (mm)	Coolant Pressure (bar)
Roughing	100–150	0.10–0.15	2.0–3.0	25–40
Finishing	150–200	0.05–0.10	0.5–1.0	30–50

Key Features and Applications for Copper C330 (Leaded Copper)

Machining Process	Function and Benefit for Copper C330 (Leaded Copper)
CNC Machining	Achieves high-precision for mass-produced connectors, contacts, and fittings.
CNC Milling	Ideal for flat surfaces, slots, and intricate features for electrical parts.
CNC Turning	Suitable for producing rods, shafts, and other cylindrical parts with precise dimensions.
CNC Drilling	Drills holes with high accuracy, up to 10 times hole diameter ratio for connectors.
CNC Boring	Perfect for enlarging holes with tight tolerances and smooth finishes for tubes.
CNC Grinding	Provides excellent surface finishes with tight tolerances for electrical components.
Multi-Axis Machining	Ideal for producing complex parts with intricate geometries for high-performance connectors.
Precision Machining	Ensures tight tolerances for electrical parts, improving fit and functionality.
EDM Machining	Used for creating micro-features in small-scale components like electrical contacts.

Surface Treatment for Copper C330 CNC Parts

Electroplating: Adds a 5–10 µm layer of nickel or silver for improved corrosion and wear resistance.
Polishing: Achieves Ra 0.2–0.4 µm surface smoothness, improving conductivity and aesthetics.
Brushing: Produces a matte finish with a uniform appearance for decorative and functional applications.
PVD Coating: Adds a 2–5 µm hard, durable coating, enhancing wear resistance and aesthetics.
Passivation: Improves corrosion resistance by up to 30%, extending component lifespan.
Powder Coating: Provides a 50–100 µm protective coating for durability and enhanced UV resistance.
Teflon Coating: Adds a low friction, chemical-resistant layer ideal for sliding components.
Chrome Plating: Adds a shiny, durable finish (10–20 µm thickness) for corrosion protection and high-load applications.

Industry Applications of Copper C330 (Leaded Copper)

Aerospace Industry: Ideal for producing electrical connectors, pins, and other components subject to high-volume machining.
Electrical & Power: Used for terminals, busbars, and other power distribution components requiring easy fabrication.
Automotive Industry: Suitable for high-volume connectors and electrical components manufacturing in automotive systems.