Brass fasteners are fastening components such as nuts, bolts, screws, washers, rivets, inserts, anchors, and studs manufactured from brass, a copper–zinc alloy.
The copper–zinc composition provides an excellent balance of corrosion resistance, malleability, electrical conductivity, and aesthetic appeal, making brass fasteners ideal where durability, appearance, and chemical or electrical compatibility are important.
Typical Chemical Composition
| Brass Grade | Cu % | Zn % | Other Elements | Typical Use |
|---|---|---|---|---|
| Free-Cutting Brass (C36000) | 60 – 63 | 33 – 37 | Pb 2 – 4% | Machined fasteners |
| Cartridge Brass (C26000) | ~70 | ~30 | — | Cold-formed fasteners |
| Naval Brass (C46400) | ~60 | ~39 | Sn ~1% | Marine fasteners |
| Red Brass (C23000) | ~85 | ~15 | Sn | Plumbing fasteners |
| Lead-Free Brass | 60 – 75 | Balance | Bi, Si | Drinking water systems |
Fastener performance depends strongly on alloy selection and forming process, not just size.
Physical Properties
| Property | Typical Range |
|---|---|
| Density | 8.4 – 8.7 g/cm³ |
| Melting Range | 880 – 950 °C |
| Electrical Conductivity | 20 – 30% IACS |
| Thermal Conductivity | 100 – 120 W/m·K |
| Thermal Expansion | 18 – 21 µm/m·°C |
| Magnetic Property | Non-magnetic |
| Appearance | Yellow to reddish gold |
Mechanical Properties
| Property | Typical Range |
|---|---|
| Tensile Strength | 300 – 550 MPa |
| Yield Strength | 120 – 400 MPa |
| Elongation | 10 – 50% |
| Hardness | 80 – 180 HB |
| Shear Strength | ~0.6 × tensile |
| Modulus of Elasticity | ~100 GPa |
Brass fasteners are not intended to replace high-strength steel fasteners in load-critical joints.
Metallurgical Behavior
Alpha-phase brass provides ductility and corrosion resistance, while alpha–beta brass offers higher strength and hardness. If present, lead improves machinability but reduces ductility.
Strengthening occurs mainly through solid-solution strengthening and cold working such as thread rolling, drawing, and heading. Brass fasteners cannot be heat-treated for hardening.
Key Characteristics
✔ Excellent corrosion resistance
✔ Non-magnetic
✔ Non-sparking (ATEX safe)
✔ Good electrical conductivity
✔ Attractive appearance
✔ Easy machining and forming
✔ Resistant to atmospheric and water corrosion
Limitations:
Lower strength than steel fasteners
Not suitable for high-load structural joints
Manufacturing Processes
| Process | Suitability |
|---|---|
| Cold heading | Excellent |
| Thread rolling | Excellent |
| CNC machining | Excellent |
| Hot forging | Good |
| Casting | Limited |
| Welding | Poor |
| Brazing / Soldering | Excellent |
| Plating | Excellent |
Available Forms & Finishes
Screws, bolts, nuts, washers, studs, anchors, threaded inserts, and custom fasteners
Finishes include natural brass, polished, nickel plated, chrome plated, and antique finishes.
Applications
Electrical terminals and switchgear
Plumbing fittings and sanitary fixtures
Low-load marine and decorative hardware
Architectural hinges, handles, and fittings
Precision instruments, HVAC, and light machinery
Advantages
✔ Corrosion resistant
✔ Long service life
✔ Electrical conductivity
✔ Non-sparking safety
✔ Attractive finish
✔ Easy installation
✔ Low maintenance
Why Choose Brass Fasteners?
Brass fasteners are the preferred choice when corrosion resistance, electrical conductivity, non-magnetic behavior, aesthetic appeal, and precision machining are more important than maximum mechanical strength.
Brass vs Steel Fasteners
| Property | Brass | Steel |
|---|---|---|
| Corrosion Resistance | Excellent | Requires coating |
| Magnetic | No | Yes |
| Electrical Conductivity | Good | Poor |
| Strength | Moderate | High |
| Aesthetic Appeal | Excellent | Poor |