6061-T6 vs C360 Free-Cutting Brass
6061-T6 aluminum and C360 free-cutting brass are both popular CNC materials, but they suit different priorities. 6061 is the default structural aluminum: light, inexpensive, corrosion-stable, and versatile. C360 is the benchmark for machinability, with excellent conductivity, wear resistance, and a decorative finish. The density and cost contrast is large, and the choice usually hinges on weight versus machinability and appearance.
The verdict
Choose 6061-T6 aluminum for lightweight, low-cost structural and machined parts where corrosion stability and strength-to-weight matter. Choose C360 brass when you need top-tier machinability, electrical conductivity, wear resistance, or a decorative finish, accepting its much higher density and cost.
Side-by-side data
| Property | 6061-T6 | C360 Free-Cutting Brass |
|---|---|---|
| Category | Aluminum | Copper Alloy |
| Density (g/cm³) | 2.7 | 8.5 |
| Tensile strength (MPa) | 310 | 340 |
| Yield strength (MPa) | 276 | 125 |
| Elongation (%) | 12 | 53 |
| Hardness | 95 HB | 78 HB |
| Max service temp (°C) | 170 | 200 |
| Machinability | ●●●●● | ●●●●● |
| Corrosion resistance | ●●●●● | ●●●●● |
| Relative cost | ●●●●● | ●●●●● |
| Thermal cond. (W/m·K) | 167 | 115 |
| Typically used for | All-round structural & machined parts — the default aluminum | High-speed machined fittings & valves |
Which should you choose?
Choose 6061-T6 Aluminum when…
- Weight matters: 2.7 g/cc is roughly one-third the density of C360 brass (8.5 g/cc)
- Lower cost is preferred: 6061 rates 2.0/5 vs brass's 3.0/5
- Building all-round structural and machined parts (the default aluminum)
- Good corrosion stability is needed without plating (3.5/5)
- Higher thermal conductivity helps (167 vs 115 W/m-K)
- You want versatility across CNC, sheet metal, and extrusion
Choose C360 Brass when…
- Maximum machinability is the goal: C360 rates 5/5, the benchmark free-cutting alloy
- High-speed, high-volume turned fittings and valves are being produced
- Good electrical conductivity is required for connectors or terminals
- A decorative gold finish or polished appearance adds value
- Wear resistance and self-lubricity benefit the part
- Higher elongation is useful: 53% vs 6061's 12%
Key differences that matter
- Density contrast is large: C360 brass (8.5 g/cc) is roughly three times the mass of 6061 aluminum (2.7 g/cc).
- C360 is the machinability benchmark (5/5) vs 6061's still-good 4.5/5, favoring high-volume screw-machine work.
- 6061 is lighter and cheaper (cost 2.0/5 vs 3.0/5), the default for structural and weight-sensitive parts.
- C360 offers better electrical conductivity and a decorative finish; 6061 offers better strength-to-weight.
- 6061 has higher tensile strength (310 vs 340 MPa nominal for brass is close, but yield differs: 276 vs 125 MPa).
- Both resist corrosion well (6061 3.5/5, C360 4.0/5) and share a similar role in fittings and machined parts.
- 6061 conducts heat better (167 vs 115 W/m-K); brass conducts electricity better, a key selection driver.
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Open the Material SelectorGet a Quote →Frequently asked questions
Is C360 brass really easier to machine than aluminum?
Yes. C360 free-cutting brass rates 5/5 on machinability, the top of the scale and a long-standing benchmark. It cuts cleanly at high speeds with excellent chip control, ideal for high-volume turned fittings. 6061-T6 is also very machinable at 4.5/5, but C360 is the standard for fast, repeatable screw-machine work.
How much heavier is C360 brass than 6061 aluminum?
About three times heavier. C360 has a density of 8.5 g/cc versus 2.7 g/cc for 6061-T6. For any weight-sensitive part, aluminum is the clear choice. Brass earns its weight penalty only when its machinability, conductivity, wear resistance, or decorative finish are genuinely required.
Which is cheaper, 6061 or C360?
6061-T6 aluminum is cheaper, rating 2.0/5 on cost versus 3.0/5 for C360 brass. Combined with its far lower density, aluminum delivers significantly lower cost per part by both material price and weight. Brass is selected for its specific properties rather than for economy.
When does brass beat aluminum despite the weight and cost?
When you need top machinability for high-volume turned parts, good electrical conductivity for connectors, wear resistance in valves and fittings, or a decorative gold finish. C360's 5/5 machinability and conductivity justify its higher density and cost in plumbing, electrical, and precision turned components.
Property values are typical/nominal figures for early-stage guidance only and vary by temper, grade, supplier and heat treatment. Confirm critical specifications against a certified datasheet or with an mfgiq engineer before production.