C510 Phosphor Bronze vs C630 Nickel-Aluminum Bronze
C510 phosphor bronze and C630 nickel-aluminum bronze are both wrought copper alloys, but they target different jobs. C510 is a spring-and-contact bronze valued for fatigue resistance, formability and good conductivity in strip form. C630 is a high-strength structural and marine bronze for propellers, pump parts and valve components that must carry heavy load in seawater.
The verdict
Choose C510 phosphor bronze for springs, electrical contacts, bushings and formed strip parts where fatigue life and corrosion resistance matter at moderate strength. Choose C630 nickel-aluminum bronze when the part is structural and seawater-exposed — propellers, pump bodies, valve stems — needing ~620 MPa nominal tensile and superior erosion/cavitation resistance.
Side-by-side data
| Property | C510 Phosphor Bronze | C630 Nickel-Aluminum Bronze |
|---|---|---|
| Category | Copper Alloy | Copper Alloy |
| Density (g/cm³) | 8.86 | 7.58 |
| Tensile strength (MPa) | 470 | 620 |
| Yield strength (MPa) | 410 | 310 |
| Elongation (%) | 15 | 15 |
| Hardness | 85 HRB | 170 HB |
| Max service temp (°C) | 225 | 300 |
| Machinability | ●●●●● | ●●●●● |
| Corrosion resistance | ●●●●● | ●●●●● |
| Relative cost | ●●●●● | ●●●●● |
| Thermal cond. (W/m·K) | 69 | 42 |
| Typically used for | Springs, contacts & bushings | Marine propellers & pump parts |
Which should you choose?
Choose C510 Phosphor Bronze when…
- You're making springs, contacts or terminals that need good fatigue life and resilience
- Parts are stamped or formed from strip and benefit from C510's ductility (~15% elongation)
- Sleeve bushings need a low-friction bronze at moderate load
- Good general corrosion resistance (4.0) is enough for the environment
- Better machinability (3.0 vs 2.5) and lower cost help part economics
- Yield strength near ~410 MPa nominal covers the spring or contact load
Choose C630 Nickel-Aluminum Bronze when…
- The part is structural and high-load — ~620 MPa tensile, 170 HB nominal
- It is immersed in seawater and must resist erosion and cavitation (corrosion 4.5)
- You're making propellers, impellers, wear rings or valve/pump components
- Higher service temperature (~300°C nominal) is required
- The part is cast or forged to a substantial section, not formed from thin strip
- Strength-to-weight benefits from the lower 7.58 g/cm³ density
Key differences that matter
- C630 is stronger (~620 vs 470 MPa tensile, 170 HB vs 85 HRB nominal); C510 is more about spring resilience than peak strength.
- C510 is a strip/spring alloy — its ductility and fatigue resistance suit stamped contacts and formed bushings.
- C630 resists seawater corrosion, erosion and cavitation better (4.5 vs 4.0) and is the marine-component standard.
- C510 machines and forms more readily (3.0 vs 2.5) and costs less (3.0 vs 3.5).
- C630's lower density (7.58 vs 8.86 g/cm³) helps rotating marine parts.
- C510 tops out around 225°C and C630 around 300°C nominal.
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Open the Material SelectorGet a Quote →Frequently asked questions
Can C510 be used in seawater like C630?
C510 has good general corrosion resistance (4.0) and is used in marine-adjacent hardware, but C630 is purpose-built for immersed seawater service with superior erosion and cavitation resistance (4.5). For propellers, pumps and valves continuously in seawater under load, C630 is the correct choice; C510 suits contacts and springs in milder exposure.
Why pick C510 for springs over C630?
Phosphor bronze is engineered for spring temper — high resilience, fatigue resistance and the ductility to be formed into strip springs and contacts. C630 is far stronger but is a structural/marine casting and forging alloy, not optimized as a fatigue-loaded spring strip. For spring contacts, C510's formability and fatigue life win.
Which is more cost-effective to produce?
C510 generally — it costs less (3.0 vs 3.5) and machines and forms more easily (3.0 vs 2.5), so finished springs, contacts and bushings are cheaper to make. C630's higher strength and hardness raise machining cost, but that's justified when its load capacity and seawater performance are actually required.
Are these interchangeable for bushings?
Only loosely. C510 makes a fine moderate-load bushing with low friction and good fatigue life. C630 handles much higher contact stress and seawater wear but is harder to machine. Match the bushing to load and environment: C510 for general duty, C630 for heavily loaded or marine wear surfaces.
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.