Bobon Copper

Products / C70250

C7025 Copper-Nickel-Silicon Strip

C7025 combines high strength with conductivity of 40 % IACS or better and good resistance to stress relaxation at elevated temperature. It is widely specified for fine-pitch connector terminals and lead frames where beryllium-free material is required.

Equivalent designations

SystemDesignation
UNSC70250
ENCuNi3SiMg
JISC7025

Typical applications

  • Fine-pitch connector terminals
  • Board-to-board and I/O contacts
  • Lead frames
  • Automotive terminals
  • Relay springs

Chemical composition (%)

ElementContent
Ni2.2 – 4.2
Si0.25 – 1.2
Mg0.05 – 0.30
CuBalance

Physical properties

PropertyValue
Density8.82 g/cm³
Elastic modulus131 GPa
Electrical conductivity≥ 40 % IACS

Tempers and tensile strength

TemperConditionTensile strength (MPa)
TM00Mill hardened620 – 760
TM02Mill hardened655 – 825
TM03Mill hardened690 – 860

Values follow the limits of the governing standard. The mill test certificate for each lot states the measured values.

Supply range

ItemValue
ThicknessTO CONFIRM
WidthTO CONFIRM
FormCoil, slit to width
Minimum orderTO CONFIRM
Lead timeTO CONFIRM

Questions buyers ask

How does C7025 compare with beryllium copper?

C7025 has lower peak strength than age-hardened C17200 but roughly twice the conductivity, contains no beryllium and needs no heat treatment after stamping. For many terminal designs it is the more economical choice.

Do you also supply C7035?

Yes. C7035 is a cobalt-bearing copper-nickel-silicon alloy with higher strength than C7025, used where thinner gauges must carry the same contact force. Send us the temper and gauge you need.

What documents come with each shipment?

The original mill test certificate for the heat lot, a packing list with coil numbers, and RoHS and REACH declarations.

Request a quotation

Send us the grade, temper, thickness, width and quantity. We reply within one working day.

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