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The sessile drop technique is used to measure the contact angles of molten Si, Sn, Cu and Ni in contact with mono-and polycrystalline cz-SiC as well as CVD 13-SIC in purified argon atmosphere and at various temperatures. The contact angle of silicon, near its melting point, is about 38 ~ on a mono-as well as polycrystalline 0~-SiC substrate and about 41.5 ~ on I3-SiC. Tin does not wet the SiC. Using data from the available literature, the work of adhesion and the interfacial energy between SiC and Si or Sn were calculated. In the ~-SiC-Sn system, both quantities are linearly dependent on temperature in the investigated temperature range 523-1 073 K. The metals copper and nickel react with silicon carbide. The silicon content of the copper drop depends on the annealing temperature. The nickel drop after cooling forms the compound Ni3Si 2. The interferometric measured groove angle of SiC (thermal etching) in vacuum at 2020 K gives a mean value of 157.6 _+ 5.8 ~ !ntroductionModern engineering ceramics possess significant advantages over metallic materials for a variety of technical applications. Existing disadvantages, such as brittleness and insufficient reproducibility of properties, are being addressed by current research projects. Furthermore, suitable techniques for joining ceramic materials with each other and with metals are being developed [1]. With regard to the commercial viability of engineering ceramics, techniques are required for the joining of ceramics to metallic components [2]. Brazing, diffusion welding and those processes in which one of the work pieces involved is fused are suitable for application in the hightemperature range which is of particular interest.For high-temperature structural applications, silicon carbide-based ceramics are currently being considered due to their good mechanical strength and oxidation resistance at elevated temperatures.Generally, the wettability conditions between ceramics and liquid-metal phases are of importance in the development of joining techniques. The correlation between the wetting and the bonding behaviour at the interface in solid-liquid-vapour systems in thermodynamic equilibrium is given by the equationwhere Ysv, YLV are the surface energies of the solid and liquid phases, respectively, YSL is the interfacial energy of solid-liquid, and W~ the work of adhesion, defined as the work needed to separate an interface [3]. An established method for studying the interfacial phe-

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