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

Rodney Williams

Rodney Williams

Vice President bedra, Inc.
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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