The directionally solidified Si-TaSi2 eutectic in situ composites, which have highly aligned and uniformly distributed TaSi2 fibers embedded in the Si continuous matrix, are obtained by electron beam floating zone melting (EBFZM) technique at the solidification rate range 0.3-9.0 mm/min. The preferential orientation of the Si-TaSi2 eutectic is also studied by selected area electron diffraction (SAED), which is [0 (1) over bar (1) over bar ]Si parallel to[0 0 0 1]TaSi2 and (0 (1) over bar 1)Si parallel to(0 (1) over bar 1 1)TaSi2. Moreover, field emission properties of the Si-TaSi2 eutectic in situ composites are investigated by transparent anode imaging technology. Approximately straight F-N curves show that this material has excellent field emission properties. (C) 2007 Elsevier B.V. All rights reserved.