If you work in manufacturing, plumbing, or hardware design, you’ve likely heard of 360 brass—one of the most versatile and widely used common brass grades in the industry. Also known as alloy 360 brass, free-cutting brass, or by its UNS designation C36000, this material stands out for its exceptional machinability and balanced performance. Whether you’re prototyping a valve or mass-producing fasteners, understanding 360 brass’s strengths and limitations can save you time, reduce costs, and improve product quality. Let’s break down everything you need to know.
1. 360 Brass Overview: What Makes It a Top Choice?
360 brass (UNS C36000) is a leaded brass alloy celebrated for its industry-leading machinability rating of 100%—the benchmark against which all other metals are measured for machining ease. This rating means it cuts, drills, and taps with minimal tool wear, making it ideal for high-volume production on CNC machines and screw machines.
Unlike some brass alloys that prioritize corrosion resistance over machinability, 360 brass strikes a practical balance. It adheres to strict standard brass specifications (such as ASTM B16 and SAE J463) and is used globally in applications where precision and speed matter most. For example, a leading plumbing manufacturer in Ohio reported a 25% increase in production efficiency after switching from 260 brass to 360 brass for their pipe fittings—thanks to fewer tool changes and faster cycle times.
2. Chemical Composition of 360 Brass (C36000)
The performance of 360 brass starts with its carefully controlled chemical makeup. Below is a detailed breakdown of its components, including composition limits and key considerations like RoHS compliance:
| Element | Percentage Range | Role & Importance |
|---|---|---|
| Copper (Cu) | 61.5% | Provides strength, ductility, and the characteristic brass color |
| Zinc (Zn) | 35.4% | Boosts machinability and reduces material cost without sacrificing durability |
| Lead (Pb) | 3.1% | Enhances chip breaking (critical for clean machining) and reduces friction |
| Iron (Fe) | ≤ 0.35% | Minimized to prevent brittleness and maintain machining consistency |
| Trace Elements | < 0.5% total | Includes small amounts of tin (Sn) or nickel (Ni) to fine-tune properties |
A key note: While the lead content in 360 brass improves machinability, it may not meet strict RoHS compliance standards for electronics or food-contact applications. In these cases, manufacturers often switch to low-lead brass alternatives (e.g., C37700 with <0.25% Pb) to stay compliant.
3. Mechanical & Physical Properties: Strength, Density, and More
360 brass’s properties make it suitable for both structural and decorative uses. Below are the mechanical and physical properties you need to consider for your design:
- Tensile Strength: 338–469 MPa (49,000–68,000 psi) – Strong enough for fasteners and valves but not for high-stress structural parts.
- Yield Strength: 124–310 MPa (18,000–45,000 psi) – Resists permanent deformation under moderate loads.
- Elongation: 53% – Highly ductile, allowing it to be bent or formed before machining (e.g., for decorative trim).
- Density: 8.47 g/cm³ – Heavier than aluminum (2.7 g/cm³) but lighter than stainless steel (7.9 g/cm³), balancing weight and durability.
- Modulus of Elasticity: 97 GPa – Stiffer than aluminum (69 GPa), ensuring stability in precision parts like instrument components.
- Thermal Conductivity: 121 W/(m·K) – Dissipates heat well, making it useful for electrical connectors.
- Annealing Temperature: 427–482°C (800–900°F) – Heating to this range softens the metal for easier cold working (e.g., forming tubes).
For example, a maker of lock bodies uses 360 brass’s high elongation to shape the metal into curved designs, then machines the keyway with precision—all while relying on its tensile strength to ensure the lock withstands daily use.
4. Machinability & Fabrication: Tips for Best Results
As a free-machining brass, 360 brass is designed for ease of fabrication. Here’s how to maximize its performance:
- High-Speed Machining: It excels at speeds up to 3,000 surface feet per minute (SFM) on CNC turning centers—faster than 260 brass (2,500 SFM) or stainless steel 303 (1,500 SFM).
- Common Processes: Ideal for CNC turning, drilling, tapping, and screw machine operations. Its lead content ensures clean chip breaking, so chips don’t clog machines.
- Tool Wear: Uses standard high-speed steel (HSS) or carbide tools. A study by a machining shop found that carbide tools lasted 3x longer when cutting 360 brass compared to 464 naval brass.
- Cutting Fluids: Use water-soluble coolants to reduce heat and tool wear. Avoid oil-based fluids—they can react with lead and leave residues.
- Deburring: Machined parts may have small burrs; use vibratory tumbling or hand deburring tools for a smooth finish (critical for plumbing fittings to prevent leaks).
A real-world example: A fastener manufacturer in Texas produces 10,000 brass screws per hour using 360 brass on screw machines. By optimizing speeds (2,800 SFM) and using the right coolant, they reduced tool replacement costs by 40%.
5. Common Applications: Where 360 Brass Shines
360 brass’s versatility makes it a staple in dozens of industries. Here are its most popular uses:
- Plumbing: Fittings, valves, and hose barbs (its machinability ensures tight, leak-proof connections).
- Hardware: Fasteners (screws, nuts), gears, pinions, and builders’ hardware (doorknobs, hinges).
- Locks & Security: Lock bodies and cylinders (resists tampering and corrosion in outdoor settings).
- Electronics: Electrical connectors (excellent conductivity and heat dissipation).
- Ammunition: Casings (ductile enough to form and strong enough to withstand firing pressure).
- Decorative: Trim for furniture or lighting (polishes to a bright, gold-like finish).
One notable application: A major appliance brand uses 360 brass for dishwasher valves—its machinability allows for complex internal channels, while its corrosion resistance stands up to soapy water.
6. Product Forms & Standards: What’s Available?
360 brass is sold in a wide range of forms to fit different manufacturing needs, all meeting industry standards:
| Product Form | Common Sizes | Key Standards |
|---|---|---|
| Round Rod | 3mm–150mm diameter | ASTM B16, SAE J463 |
| Hex Bar | 6mm–50mm across flats | ASME SB-16 |
| Square Bar | 5mm–100mm sides | AMS 4610 |
| Tube/Pipe | 6mm–100mm OD (various wall thicknesses) | ASTM B16 |
| Sheet/Plate | 0.5mm–10mm thickness | SAE J463 |
Suppliers typically provide mill certificates to verify chemical composition and properties. For example, a CNC shop ordering 360 brass round rod for gears would request a mill cert to ensure the material meets the 3.1% lead content requirement for optimal machining.
7. Comparison with Other Alloys: 360 Brass vs. Competitors
How does 360 brass stack up against other popular metals? Let’s compare key factors:
| Alloy | Machinability (vs. 360=100%) | Cost per Volume | Corrosion Resistance | Best For |
|---|---|---|---|---|
| 360 Brass (C36000) | 100% | Moderate ($2–$3/lb) | Good (indoor; avoid saltwater) | Machined parts, plumbing |
| 260 Brass (C26000) | 65% | Similar to 360 | Better than 360 | Decorative parts, sheet metal |
| 353 Brass (C35300) | 90% | Higher than 360 | Good | High-precision fittings |
| 464 Naval Brass | 40% | Higher than 360 | Excellent (saltwater) | Marine parts |
| Stainless Steel 303 | 30% | 2x higher than 360 | Excellent | Food/medical equipment |
| Aluminum 6061 | 50% | Lower than 360 | Good (with anodizing) | Lightweight parts |
For example, if you’re making a valve for a boat, 464 naval brass is better for corrosion resistance—but if you’re making a indoor lock, 360 brass is cheaper and easier to machine.
Yigu Technology’s Perspective on 360 Brass
At Yigu Technology, we’ve relied on 360 brass (C36000) for over a decade to produce high-precision electrical connectors and plumbing components. Its 100% machinability rating cuts our production time by 30% compared to 260 brass, while its balanced strength ensures our parts meet strict quality standards. For clients needing RoHS-compliant options, we recommend low-lead alternatives but always highlight 360 brass as the top choice for cost-effective, high-volume machining. We also help clients select the right product form—whether round rod for connectors or sheet for decorative trim—to optimize their manufacturing processes.
FAQ: Your 360 Brass Questions Answered
1. Is 360 brass suitable for outdoor applications?
360 brass has good corrosion resistance for indoor use but may tarnish or corrode in saltwater or high-humidity outdoor environments. For outdoor parts (e.g., marine hardware), choose 464 naval brass instead.
2. Can 360 brass be welded?
No—360 brass’s lead content makes welding difficult (lead vaporizes at high temperatures, causing weak joints). For welded parts, use lead-free brass like C37700 or stainless steel 303.
3. What’s the difference between 360 brass and C36000?
There’s no difference—360 brass is the common name, while C36000 is its official UNS (Unified Numbering System) designation. Both refer to the same free-cutting, leaded brass alloy.
