7075 aluminum alloy ingots were prepared by the process of low frequency electromagnetic casting (low frequency electromagnetic casting = LFEC) and conventional direct chill (direct chill = DC) casting, respectively. The effects of low frequency electromagnetic field on microsegregation were investigated from eutectic analysis and electro probe microanalysis (EPMA). It was found that the amount of the eutectic, which was composed of a-Al (aluminum phase), T phase and MgZn 2 was decreased markedly. In contrast, the solute concentration profiles which depend on solid fraction were increased to a certain extent with the presence of low frequency electromagnetic field. The effective distribution coefficient k e was calculated, and the values of k e for solutes in the LFEC sample were bigger than those in the DC sample. The LFEC process alleviated the microsegregation in 7075 aluminum alloy.Keywords: aluminum alloy / low frequency electromagnetic casting (LFEC) / microsegregation / effective distribution coefficient / Schlüsselwörter: Aluminiumlegierung / niederfrequentes elektromagnetisches Gießen / Mikroseigerungen / effektiver Verteilungskoeffizient /

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