PHOSPHOR
BRONZE

Kiyomine Metal Industry’s phosphor bronze is an alloy composed of 3–9% Sn and 91–97% Cu, with 0.03–0.35% P added as a deoxidizing agent.

PHOSPHOR
BRONZE

Kiyomine Metal Industry’s phosphor bronze is an alloy composed of 3–9% Sn and 91–97% Cu, with 0.03–0.35% P added as a deoxidizing agent.

Phosphor Bronze Alloy Lineup

Kiyomine’s phosphor bronze is an alloy composed of 3–9% Sn, 91–97% Cu, and 0.03–0.35% P added as a deoxidizer.
Within this composition range, higher tin(Sn) content enhances strength and spring properties, while lower tin content improves electrical conductivity.
C5111, which contains 4% Sn, has somewhat lower spring properties but is particularly suitable for applications requiring electrical conductivity. Compared to other phosphor bronzes, its lower tin content also makes it more cost-effective.
Spring-grade phosphor bronze offers excellent strength, corrosion resistance, and superior spring properties and workability compared to other types of phosphor bronze, making it ideal for high-performance spring applications.

ApplicationGeneral UseSprings
Product NameC5212C5191C5102C5111C5240C5210
Chemical Composition
[wt.%]
CuRemRemRemRemRemRem
Sn8654108
P0.20.20.20.20.20.2

Composition and Properties Overview

Chemical Composition

Product NamePhosphor BronzePhosphor Bronze for Springs
Alloy NameCDA No.C52100C51900C51000C51100C52400C52100
JIS No.C5212C5191C5102C5111C5240C5210
Chemical Composition
[wt.%]
CuRemRemRemRemRemRem
Zn-0.2-0.2-0.2-0.2-0.2-0.2
Fe-0.1-0.1-0.1-0.1-0.1-0.1
Ni------
Sn7.0-9.05.5-7.04.5-5.53.5-4.59.0-11.07.0-9.0
P0.03-0.350.03-0.350.03-0.350.03-0.350.03-0.350.03-0.35
Si------
Mn------

Physical Properties

Product NameC5212C5191C5102C5111C5240C5210
Melting Point [℃]102010431050106010001020
Poisson's Ratio0.33-0.330.330.330.33
Specific Gravity8.88.98.98.868.788.8
Electrical Conductivity [%IACS]131415201113
Thermal Conductivity [W/m・K (20℃)]6365.871845063
Elastic Modulus [GPa]110105105105100110
Coeff. of Thermal Expansion
[ppm/K (20~300℃)]
18.217.817.817.818.418.2

Mechanical Properties

Product NameC5212C5191C5102C5111C5240C5210
Tensile Strength [MPa]O345-315-305-295---
1/4H390-510390-510375-470345-440--
1/2H490-610490-610470-570410-510-470-610
H590-705590-685570-665490-590650-750590-705
EH685-635-720620-710570-660750-850685-785
SH-690-660-640-850-950735-835
ESH----950-770-885
XSH----1000--
0.2% Proof Strength [MPa]O------
1/4H------
1/2H-----260-
H----510-450-
EH----630-580-
SH----750-640-
ESH----870-690-
XSH----930--
Elongation [%]O45-42-40-38---
1/4H40-35-28-25---
1/2H30-20-15-12--27-
H12-8-7-7-11-20-
EH  5- ※1  5- ※1  4- ※1  3- ※19-11-
SH----5-9-
ESH-----5-
XSH------
Vickers Hardness [HV]O------
1/4H100-160100-16090-16080-150--
1/2H150-205150-205130-190120-180-140-205
H180-235180-230170-220150-200200-240185-235
EH210-200-240190-230170-220230-270210-260
SH-210-200-200-250-300230-270
ESH----270-245-285
XSH----290--