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Dumet Wires Lamp and Diode Grade IconDumet Wire: Copper-Clad Ni-Fe Wire

Alloy Description

Dumet wire consists of a nickel-iron core in an oxygen-free-high-conductivity copper sheath.  It  is available in various surface finishes: electrically oxidised, borax coated, nickel plated, bare (uncoated).

Dumet Wire - Lamp and Diode grade Copper-Clad Ni-Fe Alloy Wire

Borated surface finish Dumet is used in Lead-in-wires for lamps. Dumet forms a glass-to-metal seal while manufacturing these lamps. The oxidised Dumet is used in Lead-in-wires, diodes and capacitor slug leads application.


  Ni% C% Mn% Si% S% P% Fe%
Core 41 - 43 0.05 max 1.0 max 0.30 max 0.02 max 0.02 max Rest
Copper Sheath: 24 ± 2% & 26 ± 2% of the total weight
99.96% min. Copper with 0.00% Oxygen

Two other grades of are also available:

Dumet Wire: Copper-Clad Ni-Fe Alloy Wire

Surface Finish

For Borated and Oxidised Dumet, colour is as per ASTM colour standard F-29-63T. The colours have been divided into three parts.

Light Medium Dark
0.5YR - 8.5R 7.5R - 5.5R 4.5R - 2.5R

For Nickel-Plated Dumet wire, standard plating thickness is 2 microns and 4 microns.

Dumet Wire: Copper-Clad Ni-Fe Alloy Wire Applications
Dumet Wire Production

Available Dimensions

Diameter (D) (mm) Tolerance (mm) Max out-of-roundness
0.20 - 1.00 ±0.010 0.010
1.00 - 2.00 ±1% of D 1% of D


Available on many types of spools and drums depending on the customer requirements.  Common spool in use has following dimensions (mm):

Spool Type Traverse Bore Flange Tare
Dumet-SP    52 mm 48 mm 100 mm 60 gms

Barrel/drum packaging and other standard DIN spools are also available upon request. Dumet spools are individually sealed with plastic film and put in an air-tight plastic container with activated desiccant.