C70250 (ASTM B422) Alloy Data Specifications

Olin Brass Alloy C7025 is a High Performance Alloy developed to meet the increasing material requirements of inter connect designers. C7025 combines good electrical and thermal conductivity with high strength, excellent stress relaxation resistance, good solderability and plateability. This combination of properties lends the alloy to be used in a wide variety of applications including automotive and electrical connectors, semiconductor lead frames and CPU sockets. The alloy can often be substituted directly for some Be-Cu alloys. For more information contact Olin Brass Market Development Engineering at 618-258-5255, OlinBrass.com or email us at info@olinbrass.com

Chemical Composition

Copper1 Remainder
Nickel 2.2-4.2%
Silicon 0.25-1.2%
Magnesium 0.05-0.30%
Iron 0.20% max
Lead 0.05% max
Zinc 1.0% max

1Copper plus named elements, 99.5%

Physical Properties

  English Units Metrics Units
Density 0.318 lb/in3 @ 68oF 8.82 g/cm3
Thermal Conductivity 100 BTU-ft/ft2-hr-oF 172 W/moK
Electrical Resistivity 25.9 ohm circ mils/ft 4.3 microhm-cm
Electrical Conductivity (annealed) 40% IACS* 0.23 megamho/cm
Modulus of Elasticity 19,000,000 psi 131 kN/mm2
Coeff. of Thermal Expansion
  68-212oF (20-100oC) 9.3 PPM/oF 16.7 PPM/oC
  68-392oF (20-200oC) 9.6 PPM/oF 17.4 PPM/oC
  68-572oF (20-300oC) 9.8 PPM/oF 17.6 PPM/oC

*International Annealed Copper Standard

Mechanical Properties

Temper1 Tensile Strength Yield Strength2 % Elongation2 Typical 90o Bend Formability GW/BW3
ksi N/mm2 ksi N/mm2
TM00 90-110 620-760 65-90 450-620 10% min 1.0 0.5
TM02 95-120 655-830 85-110 590-760 7% min 1.5 0.5
TM03 100-125 690-860 95-120 655-830 5% min 1.5 1.0
TM03 HDC4 103-125 710-860 100-120 690-830 3% min
TR02 88 min 605 min 80 min 550 min 6% min

1Mechanical properties subject to change. Tensile strength and elongation are for reference only.
2C7025 is manufactured to a yield strength.

3DATA FOR REFERENCE ONLY. R/T = Bend Radius/Material Thickness <0.016" (0.4mm) thick, 11/16 (17.5mm) wide.
4HDC - High Density Connector. Developed specifically for socket contacts demanding very narrow tight bend performance.