Declafor
A high-machinability spinodal copper-nickel-tin alloy, tellurium-enhanced for free-cutting and a beryllium-free substitute for leaded beryllium copper (CuBe2Pb), combining high elasticity, stress-relaxation resistance, conductivity and corrosion resistance.
✓ Beryllium-free · Lead-free · Cadmium-free · REACH / RoHSHigh machinability
Tellurium addition enables free-cutting of complex, thin components.
Elasticity & stress relaxation
High elasticity, stress-relaxation resistance and formability for spring contacts.
Conductive & EMC
Fair conductivity and good electromagnetic shielding effectiveness.
Non-magnetic & corrosion-resistant
Amagnetic with high corrosion resistance and good polishing ability.
CuBe2Pb substitute
Beryllium-free alternative to leaded beryllium copper (CuBe2Pb).
Fully integrated supply
Cast to finished part in-house, full traceability.
Copper-Nickel-Tin Alloys.
Declafor (CuNi7.5Sn5Te, UNS C72670) is a high-machinability spinodal copper-nickel-tin alloy. A tellurium addition makes it free-cutting for screw-machined micro-components, while spinodal hardening delivers very high mechanical properties.
After heat treatment its microstructure becomes a nanometric alternance of tin-rich and nickel-rich areas, giving outstanding mechanical properties, high elasticity, stress-relaxation resistance and formability. The production route runs from casting and hot rolling through solution annealing, work hardening and spinodal hardening, all in-house.
Beryllium-, lead- and cadmium-free and REACH / RoHS compliant, it is non-magnetic with fair conductivity, high corrosion resistance and good electromagnetic shielding, a safe substitute for leaded beryllium copper (CuBe2Pb).
Minimum guaranteed properties.
| Grade / spec | Form | Tensile (ksi) | Yield 0.2% (ksi) | Elong. (%) | Hardness (HB) | Hardness (HRC) | Compliant with |
|---|---|---|---|---|---|---|---|
| TDX | Rods | 106 ksi | 91 ksi | 3 | 223 | 20 | — |
| THX | Rods | 144 ksi | 136 ksi | 1 | 314 | 34 | — |
| TB | Strips | 59 ksi | 54 ksi | 30 | 137 | n/a | — |
Data for information only, non-contractual. Request a certified datasheet for design allowables.
Physical properties
| Density | 8.8 g/cm³ |
| Electrical conductivity | 13 %IACS |
| Thermal conductivity | 55 W/m·K |
| Young's modulus | 115 GPa |
| Thermal expansion | 17.2 ×10⁻⁶/K |
| Magnetic permeability | n/a |
| Machinability index | 60 |
| NACE corrosion rating | 4 |
Norms & designations.
Designations
- CuNi7.5Sn5Te
- UNS C72670
- Substitute for CuBe2Pb
Forms & applications.
Rods & wires
Drawn rod and wire, 1 mm < Ø ≤ 13 mm (0.04″–0.51″), for screw-machined micro-components and contacts.
Strips & sheets
Cold-rolled strip and sheet (TB temper) for formed contacts, springs and shielding parts.
Connectors & test
Specialty connectors, test probes and electrical spring contacts, high elasticity and stress-relaxation resistance.
Coaxial connectors
Coaxial connectors for automotive and telecommunications.
Watch & eyewear micro components
High-machinability micro components for watchmaking and eyewear.
Free-cutting strength, without the beryllium.
Declafor C72670 offers a beryllium-free path to CuBe2-class performance with excellent machinability. Send your spec and we will map it to the right Declafor temper.