PHASE-TRANSFORMATIONS IN PD40NI40P20 ALLOY AT HEATING

The crystallization of Pd40Ni40P20 amorphous alloy prepared by melt qu enching was studied by transmission electron microscopy, high resoluti on electron microscopy, magnetothermal analysis, and X-ray diffraction . The crystallization begins in the near surface regions with metastab le phase formation. The parameters of the metastable phases are determ ined. The crystallized samples have a dendritic structure on the wheel side of the ribbon (with grain size about 200 nm) and nearly nanocrys talline structure on the air side (with grain sizes about 20-100 nm). Some grains of this structure are in contact with each other; others h ave amorphous intergrain layers. The structures obtained are discussed .