MgB ₂ superconducting materials have important application potential in the 20K temperature region, which is a significant advantage compared with other low-temperature superconductors (such as Nb-Ti and Nb3Sn). However, there is a big gap between its superconducting current-carrying capacity and Ni-Ti and Nb ₃ Sn, which is due to the weak magnetic flux pinning force and the poor connection between the MgB ₂ grains. Chemical doping is a simple and effective method to improve the performance of MgB ₂ . This paper studies the effect of NaCl doping on the performance of MgB ₂ . It is found that NaCl doping has a positive effect on improving the interconnection of MgB ₂ grains and refining MgB ₂ grains, and is a potentially effective method to improve the superconducting properties of MgB ₂ . In addition, all of the samples in this study showed surface pinning characteristics, but the smaller the MgB ₂ grain size, the better the match with the surface pinning characteristics described by Kramer's theory.

中文翻译：

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改善 NaCl 掺杂 MgB2 的超导性能


MgB ₂超导材料在20K温度区具有重要的应用潜力，与其他低温超导体（如Nb-Ti和Nb3Sn）相比具有显着的优势。但其超导载流能力与Ni-Ti、Nb ₃ Sn有较大差距，这是由于磁通钉扎力较弱以及MgB ₂晶粒之间的连接不良造成的。化学掺杂是提高MgB ₂性能的一种简单有效的方法。本文研究了NaCl掺杂对MgB ₂性能的影响。研究发现，NaCl掺杂对改善MgB ₂晶粒互连、细化MgB ₂晶粒具有积极作用，是提高MgB ₂超导性能的潜在有效方法。此外，本研究中的所有样品均表现出表面钉扎特性，但MgB ₂晶粒尺寸越小，与Kramer理论描述的表面钉扎特性越匹配。