摘要
为了分析缺陷对带材磁化及力学性能的影响,基于Bean临界态模型和最小磁能泛函方法,研究了含不同类型缺陷高温超导带材的电磁特性,数值模拟了磁化过程中高温超导带材的应力分布和磁致伸缩行为.研究结果表明:当缺陷偏离带材几何中心时,磁化强度出现水平分量;电磁体力使超导带材发生磁致伸缩;最大应力出现在缺陷附近,当缺陷在带材表面时,最大拉应力出现在外磁场下降阶段;当缺陷位于带材内部时,最大拉应力出现在外磁场最大时刻.根据分析结果可知,垂直磁场中的高温超导带材,其磁化及力学性能受缺陷尺寸和位置影响较大.
To analyze the influence of defect on magnetization and mechanical properties,a study of the electromagnetic properties of various high temperature superconducting strips containing different types of defects based on the Bean critical state model and the minimum magnetic energy variation method was presented. The magnetostrictive behavior and the stress distribution of the high temperature superconducting strip were numerically simulated. Results show that a horizontal component of the magnetization appears as the defect deviates from the centre of the strip. The strip exhibits a magnetostrictive phenomenon and the maximum stress arises nearby the defect on account of the action of electromagnetic body force. The moment of the maximum tensile stress appears in the magnetic field decreasing stage when a strip contains a surface defect. For the case of an interior defect,the tensile stress in a strip reaches its extreme value at the highest magnetic field. The analysis results indicate the magnetization and mechanical properties of a strip in perpendicular magnetic field have distinct dependence on the dimension and location of the defect.
引文
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