Material Guide
Bronze Properties
Bronze is a copper-tin alloy known for its corrosion resistance in seawater and excellent bearing properties. Learn when to choose bronze over brass or steel.
4 min readUpdated July 2026
Overview
Bronze is primarily a copper-tin alloy (88% Cu, 10% Sn, 2% other). It is harder and more corrosion-resistant than brass, especially in seawater. Bronze is widely used for marine fittings, pump impellers, bearings, and bushings.
Key Properties
| Property | Value |
|---|---|
| Density | 8800 kg/m³ |
| Tensile strength | 350–600 MPa |
| Melting point | 910–1040°C |
| Thermal conductivity | 75 W/m·K |
| Max service temperature | 260°C |
Advantages
- Excellent seawater corrosion resistance: One of the best metals for marine service — used for propellers, pump impellers, and seawater valves.
- Excellent bearing properties: Low friction and good embeddability — ideal for bushings and plain bearings, especially against steel shafts.
- Good casting properties: Can be cast into complex shapes — used for pump impellers, valve bodies, and large bearings.
- Non-sparking: Bronze tools don't produce sparks — used in explosive environments (gas plants, mines).
Limitations
- Higher cost than steel: Copper alloy cost makes bronze expensive for large components.
- Not for high temperatures: Loses strength above 260°C — not suitable for steam or hot gas service.
- Heavier than steel: Density of 8800 vs 7850 for steel — bronze components are heavier.
Typical Applications
- Pump impellers for seawater
- Marine fittings and hardware
- Plain bearings and bushings
- Valve seats and discs
- Non-sparking tools (gas industry)
- Sculpture and art castings
Chemical Compatibility
| Chemical | Rating |
|---|---|
| Seawater | Excellent |
| Fresh water | Excellent |
| Steam (low pressure) | Fair |
| Dilute acids | Good |
| Alkalis | Good |
| Chlorides | Good |
How CHI can help
Ask CHI about bronze properties and to recommend it for marine or bearing applications. The CHI assistant can recommend the right material for your specific application, explain chemical compatibility, and flag when a material is unsuitable for your operating temperature or environment.