In electrical power engineering, silver coatings on conductor materials are commonly used for better contact behavior and to allow higher temperatures at joints. It is known, that Al-Ag bimetal joints are not long-term stable. The system Al-Ag forms two intermetallic compounds (IMC) at temperatures below 300 deg C and usually these intermetallic compounds resulting from interdiffusion processes have worse electrical and mechanical properties compared to the pure metals (e.g. higher resistivity, high brittleness). Phase pure samples of the IMC (Ag3Al and Ag2Al) have been prepared and electrically characterized. The results show, that the resistivity is much higher than for pure Al or Ag. It was also found, that for Al-Ag bimetal interfaces being exposed to air, a reaction with oxygen takes place which reduces or even stops the growth of intermetallic compounds.
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