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观察并研究了不同Y2O3含量的Cu/Y2O3共掺杂MgB2的体系,样品通过传统的固相烧结法制备。结合扫描电镜和X射线衍射技术的分析发现,只有在5%Y2O3掺杂的样品中获得了层状组织。选择5%Y2O3含量的体系结合热分析曲线对固相反应阶段进行了动力学分析,得出最概然机理函数为Avrami-Erofeev,n=2,表达式为2[-ln(1-α)]1/2。其意义是随机形核和随后的瞬时生长。最后对动力学参数进行了计算,结果表明反应的活化能和指前因子均先趋于稳定后减小。
The system of CuB2 / Y2O3 codoped MgB2 with different content of Y2O3 was observed and studied. The samples were prepared by the conventional solid-state sintering method. Combined with SEM and X-ray diffraction analysis, it was found that only lamellar structure was obtained in 5% Y2O3-doped samples. The kinetic analysis of the solid-phase reaction was carried out using a system with 5% Y2O3 content. The most probable mechanism was Avrami-Erofeev with n = 2 and the expression was 2 [-ln (1-α) ] 1/2. Its meaning is random nucleation and subsequent transient growth. Finally, the kinetic parameters were calculated, the results show that both the activation energy and the pre-exponential factor tend to stabilize and then decrease.