Tungsten-Copper (W-Cu)

High-Conductivity Alloy with Resistance to Thermal Cycling

The material combines high electrical and thermal conductivity with resistance to thermal cycling and mechanical stability.

Copper enables efficient heat dissipation and current flow, while tungsten increases hardness, reduces wear and ensures dimensional stability under load. The synergy of both elements reduces cracking and thermal stress in demanding high-temperature environments.

Compared to pure tungsten, this alloy offers significantly better thermal conductivity and machinability while maintaining high mechanical strength.

Composition of Tungsten-Copper

  • 74

    Tungsten

    W

    Remainder

  • 29

    Copper

    Cu

    10% / 20% / 25% / 50 %

Key Properties

  • Thermal Conductivity

    WCu alloys unite the high thermal conductivity of copper with the thermal stability of tungsten up to and beyond 1500 °C. This enables rapid heat dissipation, even in scenarios where copper alone would melt and tungsten would be thermally overloaded.

  • Dimensional Stability

    The low coefficient of thermal expansion reduces thermal stress during rapid temperature changes. In EDM electrodes, this enables thousands of discharges without cracking, whereas pure copper electrodes fail much earlier.

  • Electrical Conductivity

    Depending on the tungsten ratio, WCu offers adequate conductivity for high-current applications while maintaining mechanical strength. In vacuum switches, this results in clean arc formation with minimal electrode erosion.

  • Wear Resistance

    The hard tungsten particles resist arc erosion, while the copper matrix ensures stable electrical contact. This significantly reduces material loss compared to pure copper and extends the service life in high-voltage switches.

Physical and Mechanical Properties

Property

Unit

WCu 50/50

WCu 75/25

WCu80/20

WCu 90/10

Tensile strength (Rm)

MPa

344–413

585–654

620–689

700

Electrical conductivity

% IACS

56–64

41–48

38–45

< 30

Density at 20°C

g/cm³

12.2

14.3

15

16.5

Linear expansion coefficient (20°C – 300°C)

× 10⁻⁶/K⁻¹

13

9.5

8.8

< 7.5

Thermal conductivity at 25°C

W/(m·K)

310–340

190

180

170

Elongation at 20°C

%

12.5

9

8.3

6.5

E-module

GPa

-

260

280

290

These figures represent minimum values, typical averages or defined tolerance ranges. If your application requires specific material characteristics such as defined thermal stability, increased mechanical strength or enhanced chemical resistance, we will develop a suitable variant in close cooperation with you. Get in touch to discuss your specifications.

Industrial Applications

Typical applications for WCu in industrial environments

  • Electronics and Electrical Engineering

    Copper-tungsten alloys combine high electrical conductivity with thermal stability. They are used for switching contacts, conductive tracks and heat sinks that must retain dimensional stability under continuous load.

  • Aerospace

    Copper-tungsten alloys combine high electrical conductivity with thermal stability. They are used in switching contacts, high-current connections and thermally stressed structural or heat spreader components, as they maintain dimensional stability even under continuous load.

  • Welding Technology

    With high wear resistance, good thermal conductivity and low erosion tendency, WCu alloys are suited for components exposed to thermal and electrical stress, including welding electrodes, contact tips, nozzles and holders.

  • Toolmaking

    WCu remains dimensionally stable even under thermal load and can be machined with high precision. This makes the alloy suitable for mold inserts, cutting tools, and high-precision functional components where efficient heat dissipation and dimensional accuracy are critical.

Manufacturing Process

The production of a Copper-tungsten rod involves multiple steps to achieve the desired material properties.

  • 1
    Step 1

    Raw materials and preparation

    High-purity copper and tungsten are required in powder form. The tungsten powder is produced from ammonium paratungstate (APT) by hydrogen reduction. Copper powder is typically obtained by electrolysis.

  • 2
    Step 2

    Powder blending

    Copper and tungsten powders are mixed in a defined ratio. Homogeneous distribution is essential for the consistency and performance of the final material.

  • 3
    Step 3

    Cold pressing

    The blended powder is filled into a mould and cold-pressed under high pressure. This forms a green compact with the desired shape and density.

  • 4
    Step 4

    Sintering

    The green compact is sintered in a vacuum or hydrogen atmosphere at approximately 1300 to 1500 °C.

  • 5
    Step 5

    Liquid phase sintering

    The CuW component is heated until the copper melts while the tungsten remains solid. The molten copper is drawn into the tungsten structure by capillary action, creating a dense, interconnected material.

  • 6
    Step 6

    Final machining

    The extruded bar is straightened, ground and polished to ensure dimensional accuracy and surface quality.

  • 7
    Step 7

    Quality control

    The entire production process is subject to strict quality control to ensure compliance with technical specifications.

  • 8
    Step 8

    Packaging and shipping

    CuW rods are packed using protective materials to avoid damage during transport.

This process ensures that tungsten-copper rods develop the material characteristics required for industrial use. These include high thermal and electrical conductivity, good mechanical strength, and stable dimensional accuracy under thermal cycling.

Talk to Our Material Specialists

In close cooperation with you, we analyse your requirements, provide comprehensive guidance and find the solution that fits your process best.

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