Fe/Co比对FeCoBSiNb系大块非晶合金晶化行为的影响

采用Kissinger、Ozawa和MKN法研究Fe/Co比例变化对(FexCo1-x)72B19.2Si4.8Nb4系大块非晶合金晶化行为的影响。结果表明,当x在0.3～0.7之间变化时,所制备的直径为2mm的(FexCo1-x)72B19.2Si4.8Nb4系合金棒为完全非晶结构;玻璃转变温度Tg、晶化温度Tx及晶化峰值温度Tp随加热速率的增大均向高温区移动;用Kissinger法、Ozawa法和MKN法测定的非晶合金激活能结果非常接近,其中Kissinger法和MKN法测得的结果稍大,且都呈现出Ex>Ep>Eg的规律性;随着Fe含量的增加,晶化激活能Ex先增大后减小,而阶段晶化激活能Eo最大值呈下降趋势。

Effects of Fe/Co Ratio on the Crystallization Behavior in FeCoBSiNb Bulk Amorphous Alloys

Kissinger, Ozawa and MKN methods were adopted to study the effect of Fe/Co ratios on the crystallization behavior in (FexCo1-x)72B19.2Si4.8Nb4 bulk amorphous alloys. The results show that when x ranges from 0.3 to 0.7, the as-cast (FexCo1-x)72B19.2Si4.8Nb4 alloy rods with a diameter of 2 mm are in an amorphous state. The glass transition temperature Tg, onset temperature of crystallization Tx and crystallization peak temperature Tp move towards to the higher temperature regions with increasing the heating rates. The result differences of activation energies calculated by Kissinger, Ozawa and MKN methods are not too much, among which, the results calculated by Kissinger and MKN methods are slightly larger than those calculated by Ozawa method and Ex>Ep>Eg. With increasing the Fe content, the apparatus crystallization activation energy Ex increases firstly, and then decreases, while the maximum value of local crystallization activation energy Eo presents a decline trend