Fabrication of dense iron silicides by spark plasma sintering

A suitable spark plasma sintering (SPS) condition for densifying iron silic ides was examined using three kinds of starting powders: Fe + Si mixture, a lpha -FeSi2 + epsilon -FeSi mixture, and beta -FeSi2, Dense iron silicides composed of alpha -FeSi2 + epsilon -FeSi with a relative density >95% were fabricated at 800 degreesC for 5 min, under 30 MPa, Below 700 degreesC, den sity of the sample sintered from beta -FeSi2 powder is much lower than that from the powder of alpha -FeSi2 + epsilon -FeSi mixture, Moreover, the gra in size of the sample sintered at 800 degreesC from beta -FeSi2 powder was larger than that of samples from the alpha -FeSi2 + epsilon -FeSi mixture, It is concluded that a semiconducting beta -FeSi2 phase affects the microst ructure as well as the densification behavior of the sintered samples.