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This paper describes the technology and microstructure of Al2O3-Fe functionally graded composites, FGM, obtained by slip-casting under magnetic field. Alumina a-Al2O3, provided by Alcoa (symbol A16SG), with average grain size of 0.5 µm, and iron powder, (symbol Distaloy AB) from Hoganas, with average grain size of 35 µm, were used to produce a series of specimens which differed in contents of Fe particles in Al2O3. As a source of magnetic force a permanent magnet was used. Preforms were sintered in a vacuum at temp. 1470oC. The microstructures of the specimens were quantitatively described via stereological methods. Sections, parallel to the magnetic field lines were analyzed using special image analysis software. Stereological methods presented in this work have been used to determine gradient in the volume fraction of the Fe particles and variation in their size and dispersion. These parameters are essential for controlling the technological process of interest and to design microstructure for needed properties (fracture toughness).

This paper describes technology, which can be used to obtain ceramic-metal composites with a gradient of metal particles concentration. Graded composites, have been obtained by slip casting. The gradient of iron concentration was induced by magnetic field. Microstructures of the specimens have been investigated using a light and scanning electron microscopy. Quantitative analysis of microstructures has been carried out with the help of image analyzer. The obtained results prove the possibility to produce Al2O3-Fe functionally graded materials under the magnetic field.