Copper-Aluminum Oxide (CuAl2O3)

Thermally Resistant, Highly Conductive Dispersion-Strengthened Copper Alloy

The alloy provides high temperature resistance and dimensional stability. It remains dimensionally stable even under thermomechanical load and ensures efficient transmission of electricity and heat.

Dispersed aluminium oxide particles slow down dislocation movement, prevent recrystallisation and limit grain growth. This significantly increases strength and stability at elevated temperatures, while the copper matrix ensures low-loss electrical and thermal transfer.

In comparison with standard copper alloys, CuAl₂O₃ shows noticeably longer service life in applications with continuous thermal and mechanical loading.

Composition of Copper-Aluminum Oxide

  • 29

    Copper

    Cu

    > 98.8%

  • Aluminum oxide

    Al₂O₃

    0.3% – 1.1%

Key Properties

  • Strength

    Embedded Al₂O₃ particles significantly increase the strength of the material, with only a moderate reduction in electrical conductivity. The dispersion hardening remains stable even at temperatures where pure copper would soften.

  • Wear Resistance

    The combination of soft copper and hard oxide particles results in a durable microstructure. This improves mechanical performance under load and increases heat resistance. In resistance welding electrodes, this leads to longer tool life and fewer changeovers, supporting stable operation and consistent cycle rates.

  • Thermal Strength

    Copper-alumina remains dimensionally stable and strong up to 1000 °C. Even under sustained thermal load, the alloy retains its structure and mechanical properties.

  • Low Adhesion Tendency

    Oxide particles within the copper matrix reduce sticking at the electrode tip or workpiece, even at high temperatures. This increases the number of welds per electrode and lowers cleaning effort and downtime.

Physical and Mechanical Properties

Property

Unit

Value

Tensile strength (Rm)

MPa

≤ 530

Yield strength (Rp0.2)

MPa

≥ 460

Hardness (Brinell)

HBW 2.5/62.5

150–155

Electrical conductivity

% IACS

≈77

Melting point (liquidus)

°C

1083

Softening temperature

°C

900

These figures represent minimum values, typical averages or defined tolerance ranges. If your application requires specific material characteristics such as a defined hardness or higher flexibility, we will develop a suitable variant in close cooperation with you. Get in touch to discuss your specifications.

Industrial Applications

Typical use cases for CuAl₂O₃ in industrial environments

  • Welding Technology

    The combination of high electrical conductivity, strength and heat resistance makes CuAl₂O₃ suitable for electrodes exposed to high thermal loads. It is used in demanding welding applications where dimensional stability under load is critical.

  • Aerospace

    With its strength, oxidation resistance and structural stability at elevated temperatures, CuAl₂O₃ is suitable for components subjected to extreme mechanical and thermal stress. Common uses include load-bearing parts and thermally exposed structural elements.

  • Mechanical Engineering

    With high mechanical strength and reduced tendency to stick or corrode, CuAl₂O₃ is used in tools and machine elements that face long-term stress in harsh environments.

CuAl2O3 Welding Parts

Manufacturing Process

The production of a CuAl2O3 rod involves multiple steps to achieve the desired material properties.

  • 1
    Step 1

    Powder production

    Copper and aluminium oxide powders are produced with controlled particle size and distribution. Fine particles and uniform dispersion are essential to achieve the desired mechanical properties.

  • 2
    Step 2

    Mixing and milling

    Copper (Cu) and aluminium oxide (Al₂O₃) powders are blended in a defined ratio to obtain a homogeneous mixture. This uniformity is critical for the consistency and performance of the final material.

  • 3
    Step 3

    Pressing

    The powder blend is filled into moulds and compacted under high pressure. This step defines the mechanical integrity of the rods.

  • 4
    Step 4

    Sintering

    The green compacts are heated to between 800 and 1200 °C. The copper particles begin to melt and bond with the still-solid aluminium oxide, forming a dense and thermally stable composite structure.

  • 5
    Step 5

    Cold drawing

    The sintered rods are cold drawn through dies to achieve final dimensions and surface quality.

  • 6
    Step 6

    Heat treatment

    Heat treatment is applied to optimise hardness and surface properties.

  • 7
    Step 7

    Surface treatment

    Depending on application requirements, the surface is finished by grinding, polishing or chemical methods.

  • 8
    Step 8

    Quality control

    Finished rods undergo comprehensive quality checks. Mechanical tests and structural analyses confirm compliance with specifications for strength, oxidation resistance and electrical conductivity.

  • 9
    Step 9

    Packaging and shipping

    CuAl₂O₃ rods are packed using protective materials to prevent damage during transport.

This process ensures that CuAl₂O₃ rods provide the necessary properties: high hot hardness, oxidation resistance and electrical conductivity.

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.

Contact us