The mechanochemical synthesis of thermoelectric material iron disilicide based

The iron disilicide is the cheapest thermoelectric material available for mass production of generators. The problem is one of low efficiency of iron disilicide. The efficiency can be imceased by means of doping of iron disilicide, thus making a composite material, and diminishing the grain size of iron disilicide ceramics. Mechanical alloying is the most convenient method of iron silicide production. The goal of our work was to improve the properties of iron disilicide ceramics by a method of nonconventional multicomponents doping. The mechanochemical synthesis was performed by means of high energy planetary ball mill ISSCM construction. The balls acceleration was 600 m/sec/sup 2/. The compositions of synthesized powders was follows: Fe/sub 1-x/D/sub x/Si/sub 2-y/'D/sub y/, where D,'D are Co, Al, B, Cr, Nd and x,y was from 0 to 12 at%. The synthesized powders have nanoscale grain sizes and phase compositions were the mixtures of FeSi/sub 2/ and FeSi phases. The powder compacting was performed by conventional pressing under 2-4 t/sm/sup 2/ and by explosive compacting under varied conditions. Compacted samples were sintered in a vacuum of 10/sup -6/ torr at 1150/spl deg/C and annealed at 800/spl deg/C. The properties of powders and ceramics were investigated by X-ray diffraction of synchrotron radiation. The thermoelectric properties were examined also, and compared with the properties of conventional materials.