C510 Phosphor Bronze Material Guide

Overview

C510 Phosphor Bronze, also known as C51000 Phosphor Bronze or 5% Tin Bronze, is a high-performance copper-tin-phosphorus alloy renowned for its excellent combination of strength, fatigue resistance, wear resistance, corrosion resistance, spring properties, and electrical conductivity.

Containing approximately 5% tin and a small amount of phosphorus, C510 offers significantly higher strength and elastic properties than pure copper and standard brass alloys. It is widely used in electrical, electronic, marine, automotive, aerospace, and industrial applications.

C510 phosphor bronze is widely used in:

  • Electrical Connectors
  • Spring Contacts
  • Switch Components
  • Bearings
  • Bushings
  • Fasteners
  • Marine Hardware
  • Precision Stampings

Because of its superior spring characteristics and corrosion resistance, C510 remains one of the most commonly specified phosphor bronze grades worldwide.


Material Specification

PropertyValue
Material DesignationC510 Phosphor Bronze
UNS NumberC51000
Common Name5% Phosphor Bronze
StandardASTM B103 / ASTM B139
Material FamilyCopper-Tin-Phosphorus Alloy
Density8.80 g/cm³
Magnetic PropertyNon-Magnetic
Typical Supply ConditionAnnealed, Half-Hard, Spring Temper
Standard FormsSheet, Strip, Plate, Rod, Wire

Chemical Composition

ElementContent (%)
Copper (Cu)Balance
Tin (Sn)4.20–5.80
Phosphorus (P)0.03–0.35
Zinc (Zn)≤0.30
Iron (Fe)≤0.10
Lead (Pb)≤0.05

The addition of tin significantly improves strength and corrosion resistance, while phosphorus enhances wear resistance and fatigue performance.


Mechanical Properties

Annealed Condition

PropertyValue
Tensile Strength350–500 MPa
Yield Strength150–300 MPa
Elongation20–40%
Hardness70–120 HB
Elastic Modulus115 GPa

Spring Temper Condition

PropertyValue
Tensile Strength620–850 MPa
Yield Strength500–750 MPa
Hardness180–260 HB

Physical Properties

PropertyValue
Density8.80 g/cm³
Melting Point950–1020°C
Thermal Conductivity67 W/m·K
Electrical Conductivity15% IACS
Electrical Resistivity0.115 μΩ·m
Thermal Expansion Coefficient17.8 × 10⁻⁶/K
Specific Heat Capacity377 J/kg·K

Electrical Conductivity

MaterialConductivity (% IACS)
C110 Copper100
C260 Brass28
C510 Phosphor Bronze15
C521 Phosphor Bronze13
Stainless Steel 3042

Although lower than copper and brass, C510 provides sufficient conductivity for many electrical contact applications.


Thermal Conductivity

MaterialThermal Conductivity (W/m·K)
C110 Copper390
C260 Brass120
C510 Bronze67
C521 Bronze63
Stainless Steel 30416

Corrosion Resistance

EnvironmentPerformance
Indoor EnvironmentExcellent
Fresh WaterExcellent
Marine AtmosphereExcellent
Salt WaterExcellent
Industrial EnvironmentExcellent
Chemical ExposureGood

C510 exhibits outstanding resistance to seawater corrosion and atmospheric oxidation.

Recommended surface treatments:

  • Tin Plating
  • Nickel Plating
  • Silver Plating
  • Gold Plating
  • Electropolishing
  • Passivation

Wear Resistance

PropertyPerformance
Sliding Wear ResistanceExcellent
Galling ResistanceExcellent
Bearing PerformanceExcellent
Fatigue ResistanceOutstanding

C510 is frequently used in bearing and spring applications due to its excellent wear properties.


Weldability

Welding ProcessRating
TIG WeldingGood
MIG WeldingGood
Resistance WeldingExcellent
BrazingExcellent
SolderingExcellent

Machinability

ProcessRating
CNC TurningGood
CNC MillingGood
DrillingGood
GrindingGood
StampingExcellent
FormingExcellent

Machinability Comparison

MaterialMachinability
C360 BrassExcellent
C510 BronzeGood
C521 BronzeGood
C110 CopperFair
Stainless Steel 304Moderate

Heat Treatment

Stress Relief Annealing

ParameterValue
Temperature250–350°C
Cooling MethodAir Cool

Annealing

ParameterValue
Temperature500–700°C
Cooling MethodAir Cool

Heat Treatability

PropertyPerformance
Hardening by Heat TreatmentNo
Cold Work StrengtheningYes
Spring Temper AvailableYes

C510 develops its high strength primarily through cold working.


International Equivalent Grades

StandardEquivalent Grade
UNS (USA)C51000
ASTMC510
EN (Europe)CuSn5
DIN (Germany)CW451K
JIS (Japan)C5102
ISOCuSn5
GB/T (China)QSn5-0.2

Available Forms

Product TypeAvailability
SheetYes
StripYes
PlateYes
Round BarYes
Flat BarYes
WireYes
Spring StripYes

Typical Applications

Electrical Industry

  • Electrical Connectors
  • Contact Springs
  • Switch Components
  • Relay Contacts

Electronics Industry

  • Precision Contacts
  • Battery Contacts
  • Connector Terminals
  • Shielding Components

Marine Industry

  • Marine Hardware
  • Corrosion Resistant Components
  • Fasteners

Mechanical Industry

  • Bearings
  • Bushings
  • Thrust Washers
  • Wear Plates

Automotive Industry

  • Spring Clips
  • Electrical Contacts
  • Connector Components

Aerospace Industry

  • Precision Springs
  • Electrical Hardware
  • High-Reliability Components

Manufacturing Characteristics

Manufacturing ProcessRating
CNC MachiningGood
StampingOutstanding
FormingOutstanding
WeldingGood
BrazingExcellent
SolderingExcellent
ElectroplatingExcellent

Advantages

Outstanding Spring Properties

Excellent elastic recovery and fatigue resistance.

Excellent Corrosion Resistance

Particularly suitable for marine and industrial environments.

High Strength

Much stronger than pure copper and many brass alloys.

Excellent Wear Resistance

Ideal for bearings and sliding components.

Good Conductivity

Suitable for electrical contact applications.

Long Service Life

Performs well in demanding environments.


Limitations

Lower Conductivity Than Copper

Not suitable for high-current electrical transmission.

Higher Material Cost

More expensive than brass and standard copper alloys.

Lower Thermal Conductivity

Compared with pure copper.

More Difficult to Form Than Brass

Requires higher forming forces.


Comparison with Other Bronze Grades

PropertyC510C521C544C932
Tin Content5%8%4%7%
Spring PropertiesExcellentOutstandingGoodPoor
ConductivityHigherLowerModerateLow
Wear ResistanceExcellentExcellentGoodOutstanding
Corrosion ResistanceExcellentExcellentGoodGood

Comparison with Common Copper Alloys

MaterialConductivityStrengthSpring Properties
C510 Bronze15% IACSHighExcellent
C521 Bronze13% IACSHigherOutstanding
C260 Brass28% IACSModerateGood
C110 Copper100% IACSLowPoor
Stainless Steel 3012% IACSHighExcellent

Available Surface Finishes

Raw Finishes

  • Mill Finish
  • Annealed Finish
  • Spring Temper Finish

Functional Finishes

  • Precision Stamped Finish
  • Polished Finish
  • Brushed Finish

Conductive Finishes

  • Tin Plated
  • Silver Plated
  • Gold Plated
  • Nickel Plated

Frequently Asked Questions (FAQ)

What is C510 phosphor bronze?

C510 is a copper-tin-phosphorus alloy containing approximately 5% tin, known for excellent spring properties and corrosion resistance.

What is C510 used for?

Typical applications include:

  • Electrical Connectors
  • Contact Springs
  • Bearings
  • Bushings
  • Marine Hardware

What is the equivalent material to C510?

Common equivalents include:

  • CuSn5
  • CW451K
  • C5102
  • QSn5-0.2

What is the difference between C510 and C521?

PropertyC510C521
Tin Content5%8%
ConductivityHigherLower
StrengthHighHigher
Spring PropertiesExcellentOutstanding

Is C510 suitable for springs?

Yes. C510 is widely used for precision springs and electrical contacts.

Is C510 corrosion resistant?

Yes. It performs exceptionally well in marine and industrial environments.

Can C510 be machined?

Yes. C510 offers good machinability and excellent stamping characteristics.

Why choose C510 phosphor bronze?

Because it combines:

  • Excellent Spring Performance
  • High Strength
  • Excellent Corrosion Resistance
  • Good Conductivity
  • Outstanding Wear Resistance

Is C510 suitable for marine applications?

Yes. C510 is frequently used in marine and offshore equipment.

Does GCNOV provide custom manufacturing services for C510 bronze?

Yes. GCNOV provides:

  • CNC Machining
  • Precision Stamping
  • Spring Component Manufacturing
  • Electrical Connector Production
  • Surface Plating
  • Prototype Development
  • Low-Volume Production
  • Mass Production