SOLIDIFICATION STUDY OF VERTICAL FLOAT ZONED CECU2SI2

The heavy fermion compound CeCu2Si2 has been prepared by the vertical float zone technique. A detailed microstructural study has been carrie d out on both zoned and subsequently annealed samples. The vertical fl oat zoned sample prepared from nominal copper excess alloy shows large columnar grains with good crystallinity. Examination of the as-grown samples reveals the existence of an inter-dendrite Cu-rich phase in al l samples; this phase is significantly reduced by subsequent annealing . The results are discussed in conjunction with the phase diagram and the solidification process.