C69240 silicon red brass is a copper-based alloy strengthened with silicon, offering excellent corrosion resistance, high strength, and good wear properties, making it ideal for heavy-duty mechanical components such as pump parts, valve stems, and bearings.

Chemical Composition

Elements Min (%) Max (%)
Cu 71.00 72.50
Si 1.80 2.20
Pb 0.00 0.25
Fe 0.00 0.20
Sn 0.00 0.30
Ni 0.10 0.50
Mn 0.60 1.20
P 0.06 0.12
Zn Remainder

Mechanical properties according to ASTM B371 C69240 (as per temper HO2)

Range (inch) UTS Min
(ksi)
UTS Max
(ksi)
PS Min
(ksi)
Elongation Min
(%)
Hardness
Hardness Min
(HRB)
Hardness Max
(HRB)
Round (Dia) 0.059 – 0.500 85 50 5
0.500 – 1.000 70 35 15
1.000 – 2.000 70 30 15
Hex (A/F) 0.300 – 0.500 85 50 5
0.500 – 1.000 70 35 15
1.000 – 2.000 70 30 15
Square (A/F) 0.300 – 0.500 85 50 5
0.500 – 1.000 70 35 15
1.000 – 2.000 70 30 15
Rectangle Thickness: 0.250 – 0.500 85 50 5
Width: 0.5000 – 1.000
Thickness: 0.500 – 1.000 70 35 15
Width: 1.000 – 2.000
Thickness: 1.000 – 2.000 70 30 15
Width: 2.000 – 3.000
Range (mm) UTS Min
(MPa)
UTS Max
(MPa)
PS Min
(MPa)
Elongation Min
(%)
Hardness Min
(HRB)
Hardness Max
(HRB)
Round (Dia) 1.5 12 585 345 5
12 25 480 240 15
25 50 480 205 15
Hex (A/F) 12 585 345 5
12 25 480 240 15
25 50 480 205 15
Square (A/F) 12 585 345 5
12 25 480 240 15
25 50 480 205 15
Rectangle Thickness 6 – 12 585 345 5
Width 12 – 25
Thickness 12 – 25 480 240 15
Width 25 – 50
Thickness 25 – 50 480 205 15
Width 50 – 75

PHYSICAL PROPERTIES
Density ~8.4 g/cm³
Melting Range ~950–1000 °C
Elastic (Young’s) Modulus ~110 GPa (16 × 10⁶ psi)
Shear Modulus ~42 GPa (6.1 × 10⁶ psi)
Thermal Conductivity Lower than pure copper (~50–150 W/m K)
Electrical Conductivity Moderately low compared to pure copper
FABRICATION PROPERTIES
Technique Suitability
Strength & Wear Resistance Excellent
Corrosion Resistance Excellent
Machinability Moderate (~75% relative to free-cutting brass)
Hot Working Excellent
Cold Working Poor

Typical Uses