中文摘要：

铁基二硼化镁（MgB2／Fe）超导线带材有望在20K-30K、低场下得到广泛应用．本文考虑到铁的磁导率与磁场关系的非线性，结合J-A磁滞回线方程，构建了MgB2／Fe超导带材内超导芯的磁场与外加磁场的关系的模型．通过数字计算，研究了铁基截面尺寸及不同铁基底对外场的影响，计算了影响大小与外加磁场大小的关系．这对于解释MgB2／Fe超导带材的临界电流与外场的关系、进一步分析其应用中的低频交流损耗都将具有一定意义．

英文摘要：

MgB2/Fe superconducting material looks promising for large-scale engineering applications at temperature （20K-30K） region and low magnetic field. In this paper, considering that magnetization curve of iron is non-linear, we incorporate the Jiles-Atherton ferromagnetic hysteresis model to construct the mathematical formulations of relation between the applied perpendicular magnetic field on MgB2/Fe tapes surface and the magnetic field of MgB2 core. The dependences of the magnetic relations on various cross section dimensions and various type iron-clad materials were digitally calculated based on the derived formulations. It was shown that an iron-clad shielding effect occurs within a certain range of external magnetic field. Our results will be helpful for understanding the effect of magnetic field on critical current of MgB2/Fe tapes and further analyzing the alternating current losses in MgB2/Fe tapes.