Complex pulse magnetization process and mechanical properties of spark plasma sintered bulk MgB2
Complex pulse magnetization process and mechanical properties of spark plasma sintered bulk MgB2
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DOI：
10.1016/j.mseb.2021.115390
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发表时间：
2021-09-21
影响因子：
3.6
通讯作者：
Noudem, Jacques
中科院分区：
文献类型：
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作者：
Miryala, Muralidhar;Arvapalli, Sai Srikanth;Noudem, Jacques
采用火花等离子烧结（SPS）技术制备了具有优异力学性能和超导性能的高密度MgB2块体。在37.5 K时的急剧超导转变证明了超导体的高质量。临界电流密度明显超过常规烧结体。通量钉钉图显示晶界钉钉为主，峰值位置在0.2处。与致密的热等静压块体相比，SPS块体的力学性能得到了改善，弯曲强度提高了8倍。研究了脉冲场磁化过程中MgB2块体的局部过热和复杂的捕获场形成，以阐明脉冲场磁化的局限性。
High-density MgB2 bulks with superior mechanical and superconducting properties were fabricated using spark plasma sintering (SPS). The sharp superconducting transition at 37.5 K proved high quality of the superconductors. Critical current density significantly exceeded that of conventionally sintered bulks. Flux pinning diagrams indicated dominance of grain boundary pinning, with peak position at 0.2. SPS bulks showed improved mechanical properties with 8-times higher bending strength compared to dense hot isostatic pressed bulks. Trapped field was measured at 14 K and 20 K, 1 mm above the bulk's surface, with applied pulse field up to 2 T. A local overheating together with a complex trapped field formation in the MgB2 bulks during pulse-field magnetization were studied to elucidate limitations of Pulse Field Magnetization.