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New developments in powder metallurgical composites make soft magnetic composite ͑SMC͒ material interesting for application in electrical machines, when combined with new machine design rules and new production techniques. In order to establish these design rules, one must pay attention to electromagnetic loss characteristics of SMC material. In this work, five different series of iron based SMCs are produced and studied: ͑1͒ Pure iron powder with resin; ͑2͒ sintered iron based powders; ͑3͒ pure iron powder with additions of Zn-st and carbon; ͑4͒ iron based powder alloys ͑Fe,Nb,Si͒; ͑5͒ commercially available iron powder ''Somaloy.'' The specimens were shaped as rectangular rods and characterized on a miniature single sheet tester which was calibrated to Epstein. The measured energy losses are analyzed following the loss separation theory of Bertotti, in which the total energy loss is decomposed into hysteresis loss, classical Foucault loss, and an excess loss component.

Metal matrix composites have many desirable characteristics for precision components, e.g., light weight, dimensional stability, and high thermal conductivity. The understanding of the mechanisms and processes taking place at their production is of crucial importance, since these factors are important for the properties of the composite and its future application. A theoretical model of the processes at diffusion controlled formation of TiB2 in liquid Al under microgravity has been proposed. The main features of the developed model are: mechanisms controlling the formation of the TiB2; degree of distribution of the dispersed TiB2 particles; and mean size and size distribution of the dispersed TiB2 particles. The results obtained with the aid of the proposed model were verified on our recent experiments at the STS95 space shuttle mission. The model predicts correctly the TiB2 particles distribution along the specimens and the characteristic split of the reaction zone observed experimentally.

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