Brass C360

Brass C360 is a free-machining copper alloy widely used in industries that require high-speed machining, excellent corrosion resistance, and mechanical strength.

Introduction to Brass C360

Brass C360, often called free-machining brass, is one of the most widely used copper alloys. It comprises approximately 60% copper, 30% zinc, and trace amounts of lead, making it an ideal choice for applications requiring high machinability. Brass C360 is favored in CNC machining services because of its excellent cutting qualities, which allow for the production of complex parts with high-speed machining. It also offers good corrosion resistance, especially in atmospheric and fresh-water environments.

The alloy's high machinability, corrosion resistance, and good mechanical properties make Brass C360 perfect for producing precision parts used in industries such as electronics, automotive, and plumbing. CNC machined Brass C360 parts are commonly used for fittings, valves, and components that require precise dimensions and smooth finishes.

Chemical, Physical, and Mechanical Properties of Brass C360

Chemical Composition (Typical)

Element	Composition Range (wt.%)	Key Role
Copper (Cu)	61.0–64.0%	Provides strength, corrosion resistance, and conductivity
Zinc (Zn)	35.0–37.0%	Improves strength and enhances machinability
Lead (Pb)	2.0–3.7%	Enhances machinability and lubricity
Iron (Fe)	≤0.2%	Residual element that minimally impacts properties

Physical Properties

Property	Value (Typical)	Test Standard/Condition
Density	8.4 g/cm³	ASTM B311
Melting Point	900–940°C	ASTM E29
Thermal Conductivity	120 W/m·K at 20°C	ASTM E1952
Electrical Conductivity	28–30% IACS at 20°C	ASTM B193
Coefficient of Expansion	19 µm/m·°C	ASTM E228
Specific Heat Capacity	380 J/kg·K	ASTM E1269
Elastic Modulus	105 GPa	ASTM E111

Mechanical Properties (Annealed Temper)

Property	Value (Typical)	Test Standard
Tensile Strength	310–450 MPa	ASTM E8/E8M
Yield Strength (0.2%)	220–350 MPa	ASTM E8/E8M
Elongation	25–35%	ASTM E8/E8M
Hardness	60–80 HB	ASTM E10
Fatigue Strength	~200 MPa	ASTM E466
Impact Resistance	Good	ASTM E23

Note: These values are typical for annealed Brass C360 and can vary based on specific processing conditions.

Key Characteristics of Brass C360

High Machinability

Brass C360 is known for its exceptional machinability, allowing for faster machining speeds and longer tool life than other brass alloys. It is ideal for producing parts with intricate designs and tight tolerances.

Corrosion Resistance

While not as corrosion-resistant as other brass alloys like C280, Brass C360 performs well in most atmospheric environments and offers good resistance to fresh water and mild chemical exposure.

Good Strength-to-Weight Ratio

Brass C360 combines relatively high strength with low density, making it suitable for applications where strength is important but weight savings are still necessary.

Easy Formability

Brass C360 can be easily formed into complex shapes without cracking, a significant advantage in applications requiring intricate designs.

Aesthetic Appeal

With its golden color and smooth surface finish, Brass C360 is often used in decorative applications such as jewelry, nameplates, and automotive parts.

CNC Machining Challenges and Solutions for Brass C360

Machining Challenges

Chip Formation

Due to its high machinability, Brass C360 can produce long, stringy chips, especially during high-speed cutting.

Solution: Use chip breakers to control chip formation, optimize feed rates, and apply proper coolant to facilitate chip removal and maintain a clean workspace.

Tool Wear

Brass C360 contains lead, which can cause tool wear, particularly during prolonged cutting operations.

Solution: Use carbide tools and maintain proper cutting speeds to minimize tool wear and ensure longer tool life.

Surface Finish

Achieving a high-quality surface finish can sometimes be challenging due to material lubrication properties, affecting the cutting process.

Solution: Use the right lubricants, maintain sharp cutting edges, and adjust feed rates to achieve a smooth, polished finish.

Work Hardening

Brass C360 may work-harden if subjected to excessive pressure or prolonged cutting, making further machining more difficult.

Solution: Use moderate cutting speeds and apply sufficient coolant to prevent excessive heat buildup, which causes work hardening.

Optimized Machining Strategies

Tool Selection

Parameter	Recommendation	Rationale
Tool Material	Carbide tools with a high-speed steel insert	Carbide tools withstand wear and maintain cutting efficiency
Geometry	Positive rake and sharp edges	Improves chip flow and surface finish
Cutting Speed	200–350 m/min	Helps maintain tool life and prevent material deformation
Feed Rate	0.10–0.20 mm/rev	Ensures a smooth, consistent cutting process
Coolant	Flood coolant or air blast	Reduces heat generation and improves surface finish

Brass C360 Cutting Parameters (ISO 513 Compliance)

Operation	Speed (m/min)	Feed (mm/rev)	Depth of Cut (mm)	Coolant Pressure (bar)
Roughing	200–250	0.20–0.30	2.0–3.0	25–35
Finishing	250–350	0.05–0.10	0.5–1.0	30–50

Typical Machining Methods for Brass C360

Machining Process	Function and Benefit for Brass C360
CNC Machining	Precision machining of parts with intricate shapes and fine tolerances.
CNC Milling	Ideal for producing slots, grooves, and complex shapes for fittings and valves.
CNC Turning	Used for turning cylindrical parts such as gears, valves, and connectors.
CNC Drilling	Perfect for creating holes for fasteners and fittings, ensuring accuracy.
CNC Boring	Ideal for internal machining of parts like bearings and bushings.
CNC Grinding	Provides smooth finishes for components exposed to friction, such as gears and seals.
Multi-Axis Machining	Perfect for producing complex, multi-featured parts for the aerospace and automotive industries.
Precision Machining	Delivers ultra-tight tolerances for parts used in mechanical systems requiring precision.
EDM Machining	Used for intricate shapes in parts such as connectors, fasteners, and tooling.

Surface Treatment for Brass C360 CNC Parts

Electroplating: Enhances corrosion resistance and gives electrical and decorative parts a shiny finish.
Polishing: Achieves smooth, glossy finishes for high-end components like fittings and trim.
Brushing: Provides a satin finish for industrial applications, improving aesthetics and wear resistance.
PVD Coating: Adds a durable, protective coating to enhance wear resistance and prolong the life of parts.
Passivation: Improves corrosion resistance, making parts more durable in harsh environments.
Powder Coating: Provides a thicker protective layer, suitable for parts exposed to UV light, moisture, or chemicals.
Teflon Coating: Adds chemical resistance and non-stick properties for parts exposed to harsh chemicals or friction.
Chrome Plating: Provides a glossy, highly durable finish that resists corrosion, ideal for decorative and heavy-duty applications.

Industry Applications of Brass C360

Aerospace Industry: Used for producing connectors, bushings, and valve components for aerospace systems requiring high precision and reliability.
Electrical & Power: Ideal for electrical connectors, switches, and terminals due to its high machinability and conductivity.
Automotive Industry: Suitable for creating precision components like fasteners, fittings, and parts exposed to high mechanical stress.