| The crystallization characteristics of the Fe_(80-x)Ni_xB_(20)(20≤x≤40) and (Fe_(0.5)Ni_(0.5))_(80-x)Bx(16≤x≤24) amorphous alloy systems have been investigated in detail using differential scanning calorimetry, X-ray diffraction and transmission electron microscopy. Measurements of the exothermic peak temperature (T_p) and the activation energy during crystallization were obtained by differential scanning calorimetry. In the Fe_(80-x)Ni_xB_(20) amorphous alloys activation energy for crystallization increased with increasing x, and in the (Fe_(0.5)Ni_(0.5))_(100-x)B_x amorphous alloys it decreased with increasing x. Two-step crystallization was observed in specimens with x≤18 of (Fe_(0.5)Ni_(0.5)(100-x)B_x alloys; amorphous→amorphous＋γ-(FeNi)→γ-(FeNi)＋o-(FeNi)₃B. By the X-ray diffraction, the phases of crystallization products of these amorphous alloys are (ⅰ)fcc-(Fe,Ni), t-(Fe,Ni)₃B or fcc-(Fe,Ni), o-(fe,Ni)₃B, t-(Fe,Ni)₃B for high Fe content, (ⅱ)fcc-(Fe,Ni) and o-(Fe,Ni)₃B for equal contents of Fe and Ni, and (ⅲ)o-(Fe,Ni)₃B for high B content. |
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