+86-13928348837
China Bronze CNC Machining Services - Trusted Suppliers & Factory for High-Quality Industrial Components
Bronze typically refers to a family of alloys with copper as the base, primarily alloyed with elements such as tin, aluminum, silicon, and manganese. Compared to brass (copper-zinc alloys), bronze generally offers higher strength, a lower coefficient of friction, and better chemical corrosion resistance (especially against seawater). Its outstanding wear resistance and self-lubricating properties make it irreplaceable in bearing and bushing applications.
1 C93200 / SAE 660 (High-Leaded Tin Bronze - Bearing Bronze)
- ★ Characteristics: This is the most widely used bearing bronze. The added lead forms soft particles within the alloy, providing excellent self-lubricating and anti-galling properties, making it ideal for operation under insufficient lubrication or high-load, low-speed conditions. It is easy to machine and offers good wear resistance.
- ✦ Typical Applications: General-purpose bearings, bushings, thrust washers, pump components, low-load gears.
C93200 Typical Properties (As Sand-Cast)
| Property | Value | Notes |
|---|---|---|
| Tensile Strength (MPa) | 240 – 330 | Good overall strength |
| Yield Strength (0.5% Extension, MPa) | 124 | |
| Elongation at Break (%) | 18 | Good ductility |
| Hardness (Brinell) | 65 | |
| Density (g/cm³) | 8.93 | |
| Key Composition | Cu-83%, Sn-7%, Pb-7%, Zn-3% | High lead content provides self-lubrication |
| Note: Values are typical ranges, specific to casting and processing conditions. | ||
2 C95400 (Aluminum Bronze) High Strength
- ★ Characteristics: A high-strength, high-hardness aluminum bronze. Its corrosion resistance, wear resistance, and fatigue strength are among the best of all bronzes, with performance comparable to many steels. It retains strength at elevated temperatures and offers excellent impact and cavitation resistance.
- ✦ Typical Applications: Heavy-duty bearings, gears, valve seats, pump housings, propellers and components for seawater use, chemical processing equipment.
C95400 Typical Properties (Heat-Treated Condition)
| Property | Value | Notes |
|---|---|---|
| Tensile Strength (MPa) | 620 – 760 | Very high strength, comparable to low-alloy steels |
| Yield Strength (0.2% Offset, MPa) | 275 | |
| Elongation at Break (%) | 12–18 | |
| Hardness (Brinell) | 170 – 210 | High hardness, very wear-resistant |
| Density (g/cm³) | 7.45 | Lighter than tin bronze |
| Key Composition | Cu-85%, Al-11%, Fe-4% | Tin-free, uses aluminum and iron as main alloying elements |
| Note: Values are typical ranges, specific to heat treatment condition. | ||
3 C54400 (Phosphor Bronze)
- ★ Characteristics: A tin bronze containing a small amount of phosphorus. Phosphorus increases the alloy's elastic limit, fatigue strength, and wear resistance. This material offers excellent spring properties, good wear and corrosion resistance, and is easily machined into precision parts.
- ✦ Typical Applications: Electrical connectors, springs, diaphragms, bellows, wear plates, precision gears.
C54400 Typical Properties (Cold Worked Condition)
| Property | Value | Notes |
|---|---|---|
| Tensile Strength (MPa) | 520 – 690 | High strength, especially suitable for elastic elements |
| Yield Strength (0.2% Offset, MPa) | 380 – 550 | High yield strength |
| Elongation at Break (%) | 10–15 | |
| Hardness (Rockwell B) | 78 – 90 | |
| Density (g/cm³) | 8.8 | |
| Key Composition | Cu-88%, Sn-4%, Zn-4%, P-0.2–0.5% | Phosphorus acts as a deoxidizer and enhances properties |
| Note: Values are typical ranges, specific to the degree of cold work. | ||
4 C65500 (High-Silicon Bronze)
- ★ Characteristics: A bronze with excellent corrosion resistance, particularly outstanding in sulfuric acid and sulfate environments. It combines high strength, high corrosion resistance, and good formability and weldability, making it widely used in chemical and marine industries.
- ✦ Typical Applications: Chemical processing equipment components, heat exchanger tube sheets, marine fittings, pump valves, fasteners, welded structures.
Frequently Asked Questions
What is the difference between bronze and brass?
Bronze is primarily a copper-based alloy combined with elements such as tin, aluminum, silicon, or manganese, while brass is a copper-zinc alloy. Compared to brass, bronze generally offers higher strength, a lower coefficient of friction, and superior chemical and seawater corrosion resistance.
Which bronze alloy is best for bearing and bushing applications?
C93200 (SAE 660 / High-Leaded Tin Bronze) is the most widely used bearing bronze. Its high lead content creates soft self-lubricating particles within the alloy matrix, making it ideal for high-load, low-speed, or insufficiently lubricated conditions.
Is aluminum bronze (C95400) suitable for seawater environments?
Yes. C95400 aluminum bronze offers outstanding corrosion resistance, including excellent resistance to seawater, making it a preferred choice for marine propellers, pump housings, and valve seats. It also provides exceptional cavitation and impact resistance.
Why is phosphorus added to phosphor bronze (C54400)?
Phosphorus acts as a deoxidizer during casting and significantly improves the alloy's elastic limit, fatigue strength, and wear resistance. These properties make C54400 especially suitable for springs, electrical connectors, diaphragms, and precision mechanical parts.
What makes C65500 high-silicon bronze unique compared to other bronze grades?
C65500 stands out for its exceptional resistance to sulfuric acid and sulfate environments, which most other bronze alloys cannot match. It also combines high strength with excellent formability and weldability, making it highly versatile for chemical processing and marine structural applications.
How do I choose the right bronze alloy grade for my application?
The selection depends on your specific requirements: use C93200 for general bearing and bushing applications needing self-lubrication; choose C95400 when high strength and seawater corrosion resistance are critical; select C54400 for spring and electrical connector applications requiring high elasticity; and opt for C65500 when superior corrosion resistance in chemical or marine environments is the priority.
Finishes and Post-Processing Options
The zinc alloy substrate is highly suitable for various surface treatments to enhance decoration, protection, or functionality:
Electroplating: Such as chrome, nickel, gold, or silver plating, providing a highly decorative appearance, excellent wear and corrosion resistance. This is the most common choice.
-
Passivation or Chromate Conversion Coating:
-
Powder Coating:
-
Painting:
-
Physical Vapor Deposition (PVD):
Design and Machining Considerations
-
Process Selection:
-
Design Considerations:
-
Material Selection:
Zamak 3 and 5 are suitable for the vast majority of general-purpose parts requiring good appearance and strength; ZA-8 is better for wear and bearing applications; for making rapid tooling, choose specialized alloys like Kirksite.
Ready to Start Your CNC Project?
Send us your drawings to receive professional manufacturing solutions.