Paper number 1087

MODEL OF GROWTH A IRREGULAR EUTECTICS COMPOSITE IN SITU (MMCS)

Edward Guzik

Faculty of Foundry Engineering , University of Mining and Metallurgy,
Reymonta 23 Street, 30-059 Kraków, Poland

Summary In the part comprising the author's own investigations a model of irregular eutectic growth; faceted / non-faceted (irregular composite in situ) crystallizing in such significant alloys as Fe-C and Al-Si has been presented. For the experimental verification of the elaborated model the results of the unidirectional crystallization of the irregular eutectic under in the Fe-C alloys were utilized. In the structure of the oriented graphite eutectic, the decreasing of the interlamellar spacing lambda and the protrusion l of the austenite by the leading phase graphite with the increase of growth rate nu were observed. A comparison of measured and calculated average lambda values for pure (gamma)Fe - Graphite eutectic reveals good agreement. The developed model also indicates the influence direction of the material constants of the graphite eutectic on the interlamellar spacing and protrusion on the leading phase - graphite. It was stated that such material constans as wetting angle, diffusion coefficient and Gibbs - Thomson coefficient are of great importance in the eutectic growth.
Keywords irregular eutectic, irregular composite in situ, interlamellar spacing of eutectic, unidirectional crystallization, graphite eutectic.

Theme : Metal Matrix Composites ; Microstructure/Properties Relationship

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