C69400

Alloy C69400, known as Silicon Red Brass, is a high-strength, corrosion-resistant copper-zinc-silicon alloy widely used in plumbing, marine, and industrial applications. It offers excellent resistance to dezincification, good machinability, and durability in harsh environments.


CHEMICAL COMPOSITION
Elements Min (%) Max (%)
Cu 80.00 83.00
Si 3.50 4.50
Pb 0.00 0.30
Fe 0.00 0.20
Zn Remainder

Mechanical Properties according To ASTM B371 C69400 (As per Temper HO4)
Range (inch) From To UTS Min (ksi) UTS Max (ksi) PS Min (ksi) Elongation Min (%) Hardness Min (HRB) Hardness Max (HRB)
Round (Dia) 0.250 1.000 85 - 40 15 - -
1.000 2.000 70 - 35 15 - -
2.000 3.000 65 - 35 15 - -
Hex (A/F) 0.250 1.000 85 - 40 15 - -
1.000 2.000 70 - 35 15 - -
2.000 3.000 65 - 35 15 - -
Square (A/F) 0.250 1.000 85 - 40 15 - -
1.000 2.000 70 - 35 15 - -
2.000 3.000 65 - 35 15 - -
Rectangle Thickness 0.250 1.000 85 - 40 15 - -
Width 1.000 2.000
Thickness 1.000 2.000 70 - 35 15 - -
Width 2.000 3.000
Range (mm) From To UTS Min (MPa) UTS Max (MPa) PS Min (MPa) Elongation Min (%) Hardness Min (HRB) Hardness Max (HRB)
Round (Dia) 6 25 550 - 250 15 - -
25 50 515 - 240 15 - -
50 75 450 - 240 15 - -
Hex (A/F) 6 25 550 - 250 15 - -
25 50 515 - 240 15 - -
50 75 450 - 240 15 - -
Square (A/F) 6 25 550 - 250 15 - -
25 50 515 - 240 15 - -
50 75 450 - 240 15 - -
Rectangle Thickness 6 25 550 - 250 15 - -
Width 25 50
Thickness 25 50 515 - 240 15 - -
Width 50 75

PHYSICAL PROPERTIES
Melting Point - Liquidus °F 1685 °F
Melting Point - Solidus °F 1510 °F
Density 0.296 lb/in3 at 68 °F / 8.19g/cm3
Electrical conductivity 6.2% IACS at 68 °F
Thermal conductivity 15 Btu/sq. ft/ft hr/°F at 68 °F
Coefficient of thermal expansion 68-572 11.2 · 10-6 per °F (68-572 °F)
Specific heat capacity 0.09 Btu/lb/°F at 68 °F
Modulus of elasticity in tension 16000 ksi
FABRICATION PROPERTIES
Technique Suitability
Hot Forming Excellent
Soldering Excellent
Brazing Excellent
Forgeability Good
Machinability Fair
Cold Working Poor

TYPICAL USES
  • Valves
  • Faucets
  • Propellers
  • shafts
  • fasteners
  • Plumbing
  • Sanitary Fittings
  • Marine Hardwar