Increase of the thermal conductivity of aluminum-copper compound castings by selective modification of the interface

• Applicant: Professor Dr.-Ing. Hans Jürgen Maier
• Subject Area: Metallurgical, Thermal and Thermomechanical Treatment of Materials
• Term: from 2014 to 2017
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 261481227

In the manufacture of complex heat sink components, which are used for electronics with high power densities or heat exchangers, usually copper and aluminum alloys are joined. However, the joining processes that are currently used for these materials, typically feature reduced thermal conductivity, and, in addition, possess a high complexity.With the aid of compound casting, heat sinks made from different materials might be produced during the initial casting process. For an optimal heat transfer, a metallurgically-bonded connection between materials with high thermal conductivities is essential. Using a zinc-based coating, some compound castings were produced during the preliminary investigations, and it was observed that the quality of the interface is strongly influenced by the coating material and the casting parameters.The aim of the proposed project is the production of aluminum-copper compound castings, which feature an interface with high thermal conductivity using the die-casting process. The bond zone will be examined thoroughly in order to determine the thermo-physical properties of the resulting phases as well as the influence of the different coating materials, the coating methods and the morphology of the coatings used in this project. In order to ensure an optimal thermal conductivity, it will be investigated if the formation of undesirable phases can be suppressed either during the initial manufacture of the casting or if it can be reduced afterwards by means of a heat treatment of the cast component.

• DFG Programme: Research Grants