Thermal Management Beyond the Standards: When Copper and Aluminum Are No Longer Enough

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Copper and aluminum have long been the materials of choice for heat dissipation. However, modern designs in power electronics and high-end data centers are reaching their physical limits. To manage thermal stress and save space, high-performance metals and composite materials are coming into focus.

In power electronics, heat is a limiting factor and must be dissipated through effective thermal management. Until now, copper and aluminum have been the primary materials used for this purpose. However, the requirements for thermal management are changing. Materials often need to combine physically contradictory properties. These include high strength combined with low weight, compatibility with aggressive environments, or precisely tuned thermal expansion behavior.

When exactly are high-performance materials used? Dr. Björn Reetz of Materion Brush defines the limit as the point where conventional materials fail: “We’re talking about a very narrow design margin or unfavorable combinations of properties—for example, when high thermal conductivity is required alongside extreme strength, corrosion resistance to hydrogen, or resistance to radioactive radiation. In such environments, conventional metals reach their limits.” Another crucial factor is the need for customized thermal properties, such as a specifically tailored coefficient of thermal expansion.

Clad Metals And Aluminum Matrix Composites

A key challenge in electronics is thermal stress caused by the different rates of thermal expansion between semiconductors and cooling components. This is where Materion Brush leverages its sophisticated material architectures.

“Using clad metals (permanently bonded metals, editor’s note), we can adjust the yield strength to match the expected stresses, create gradients within the component, or buffer stresses using targeted interlayers,” explains Dr. Reetz. Aluminum-matrix composites also play a key role, as they enable matched thermal expansions without compromising thermal performance.

The expert sees the greatest potential in composite material solutions: “Clad metals and composite materials are the real game-changers. They allow for a very broad and targeted adaptation to the specific application problem without having to change the underlying technology.”

A Smart Design Ensures Cost-Effectiveness

The misconception that high-performance materials are too expensive often persists. Dr. Reetz counters that taking a systems-based approach can remedy this. The overall benefits are achieved through reduced weight, less installation space, significantly greater reliability, and a longer service life. Often, it is these materials that make certain technologies possible in the first place. One example is the complete elimination of complex cooling fluids.

To further improve cost-effectiveness, Materion Brush relies on close integration with modern manufacturing processes. “We must maximize the potential of these materials through smart design. This means combining them with technologies such as additive manufacturing, focusing on forming processes rather than machining, and making a judicious selection of joining methods for plating,” says Dr. Reetz. In addition, he notes that establishing standards for high-performance materials is an important step toward limiting the variety of variants and making production more efficient. (heh)