Optical wire (CuNiZn)

CuNiZn optical wires from bedra make an impression by a flawless surface finish which is required by all renowned optical manufacturers.

Fields of application

Rim, temple, bridge, hinge, closing block & pad arm

Physical properties

Density (kg/dm³) 8.7
Melting range (°C) 1060 - 1110
E-Modulus (kN/mm²) 135
Thermal conductivity (W/m*K) 33
Coefficient of thermal expansion (10-6/K) 17.7
Electrical conductivity (MS/m) 3.3

Standardization and composition

Standard designation CuNi18Zn20
DIN 17663
Material no. 2.0740
DIN EN 12166 CW409J
Cu 62
Zn balance
Ni 18
Others max. 0,5

Other tech. Values

Annealing temp. (°C) 600 - 650
Hardness annealed (HV) 95
Hardness 80% reduced (HV) 250

Delivery program

Profiles Round wires / square profiles / flat wires / special profiles
Surface coatings Several electroplated coatings, upon request
Make-ups Spools / coils / rods / drums

Further product information

Please contact me and my team

Benjamin Mülders

Benjamin Mülders

Resistance & Special Wire Sales
bedra Germany

George Kelley

George Kelley

Sales Manager Welding & ELAS North America
bedra USA

Shawn Lv

Shawn Lv

Sales Manager ELAS Asia (without China)
bedra Hong Kong

Berkenhoff GmbH (headquarters)

  • Kinzenbach plant
  • Berkenhoffstrasse 14
  • 35452 Heuchelheim
  • Germany

Berkenhoff GmbH

  • Merkenbach plant
  • Rehmühle 1
  • 35745 Herborn
  • Germany

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