+86-13928348837
China Bronze CNC Machining: Top Suppliers and Factory for Durable Industrial Parts
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
🔩
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
💪
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
Q What is the difference between bronze and brass?
Bronze is a copper-based alloy primarily combined with tin, aluminum, silicon, or manganese, while brass is a copper-zinc alloy. Bronze generally offers higher strength, a lower coefficient of friction, and better corrosion resistance — especially in seawater — compared to brass.
Q Which bronze grade is best for bearing and bushing applications?
C93200 (SAE 660 High-Leaded Tin Bronze) is the most widely used grade for bearings and bushings. Its high lead content provides excellent self-lubricating and anti-galling properties, making it ideal for high-load, low-speed, or poorly lubricated conditions.
Q Why is C95400 Aluminum Bronze considered comparable to steel?
C95400 achieves tensile strengths of 620–760 MPa and Brinell hardness of 170–210, placing it in the same performance range as many low-alloy steels. It also maintains strength at elevated temperatures and provides excellent impact and cavitation resistance, making it suitable for heavy-duty industrial applications.
Q What role does phosphorus play in C54400 Phosphor Bronze?
In C54400, phosphorus serves as a deoxidizer during casting and significantly enhances the alloy's elastic limit, fatigue strength, and wear resistance. This makes phosphor bronze especially suitable for spring components, electrical connectors, and precision mechanical parts that require consistent elastic performance.
Q In which environments does C65500 High-Silicon Bronze perform best?
C65500 excels in chemically aggressive environments, particularly those involving sulfuric acid and sulfate solutions. It also performs well in marine environments due to its excellent corrosion resistance combined with high strength, good weldability, and formability.
Q How should I select the right bronze alloy grade for my application?
Selection depends on the key requirements of your application: choose C93200 for general bearing/bushing use with self-lubrication needs; C95400 for high-strength, heavy-duty, or marine environments; C54400 for precision spring and electrical connector applications; and C65500 for chemical processing or marine structural components requiring excellent corrosion resistance and weldability.
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.