蔡奇,刘永长,马宗青,高志明,余黎明

• 1:天津大学材料科学与工程学院 天津市材料复合与功能化重点实验室

摘要(Abstract)：

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。

关键词(KeyWords)： MgB2超导体;显微组织;动力学

Abstract:

Keywords:

基金项目(Foundation): 国家自然科学基金(51077099);; 教育部新世纪优秀人才资助计划(NCET-05-0250)

作者(Author): 蔡奇,刘永长,马宗青,高志明,余黎明

DOI: 10.13289/j.issn.1009-6264.2012.09.003

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