Advanced powdermetallurgical technologies to manufacture metal matrix composites

Powder Metallurgy offers the possibility to combine a large variety of materials. That's why new properties and combination of properties can be achieved and materials which cannot be prepared my melting technology can be obtained. In addition to conventional pressure less sintering several pressure-assisted techniques were developed in the past to manufacture composites having new compositions or improved properties due to unique microstructures. The paper will focus on metal-carbon composites with interesting thermo-physical and mechanical properties. The carbon source can be graphite, diamond or carbon nanofibers. Fast sintering technologies like spark plasma sintering can be used to avoid undesired reactions between the constituents or to tailor the reaction between the constituents to obtain new microstructures and properties. In case of carbon nanofibers subsequent forming operation (hot extrusion) can lead to 1D orientation of fibres and consequently to anisotrop ic properties. For graphite a 2 D orientation and for diamond particles a 3d orientation can be expected, consequently properties will depend from the orientation.