钛酸四丁酯掺杂对MgB2块材微观结构及超导电性的影响

摘要

MgB2 bulk samples with different titanium butoxide (TNBT) doping contents were fabricated and annealed at different temperatures.The phase composition,microstructure and elements distribution of MgB2 samples were characterized systematically by means of X-ray diffraction (XRD),scanning electron microscope (SEM) and EDX.The magnetization curves of M -H and M-T were measured using PPMS.The last results show the carbon substitution is no obvious in MgB2 bulks using TNBT as doping.This may be due to the obstacle effect of TiO2 on carbon substitution,which obtained by decomposition of TNBT.%本实验采用钛酸四丁酯为掺杂物,制备了不同掺杂量、不同热处理温度的MgB2块材样品,采用X射线衍射(XRD)、扫描电镜(SEM)、能谱分析(EDS)等分析手段对不同掺杂量和不同热处理温度样品的相成份、微观结构以及元素分布进行了详细分析,最后采用PPMS物性测试系统测试了样品的M-T和肘-H曲线,其最终结果显示,以钛酸四丁酯为掺杂物并没有发生明显的C取代,主要原因可能是其分解过程产生的TiO2阻碍了取代反应的发生.