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Al/SiC composites are used especially in automotive and aerospace industry due to the numerous advantageous mechanical properties. These end-products can be produced by casting or powder metallurgical techniques. High strength with high toughness can be reached only by perfect interfacial bonds between the matrix and reinforcing phase. To improve the interfacial bond, one of the methods is the surface coating of the SiC particles. But the metal layer of the reinforcing phase reacts with the matrix due to the high sintering temperature and long sintering time. In our research work the formation of Al-Ni intermetallic phase was investigated by Scanning electron microscopy (SEM) and X-ray diffraction measurements (XRD).

In the course of the production of Al/SiC composites made by powder metallurgical method, the interfacial bond between the reinforcing phase and the matrix is not acceptable in all cases. So the ceramic particles can suffer different kinds of damage by the stress which can mean the dropping out of the particles from the matrix, or their cracking. In order to improve the interfacial bond, the surface coating of the ceramic particles is recommended. One of the surface treatment methods is the electroless nickel plating (EN plating). The successfulness of the electroless nickel plating depends on the pre–treatment methods. By using the EN plated SiC particles in the Al/SiC composites, the nickel deposit of the silicon particles and the matrix can react with the formation of the different Al–Ni phases during the sintering. These phases were examined by scanning electron microscopy (SEM) and X–ray diffraction (XRD).