Mechanical properties of Ag/Bi2223 composite superconductors
Mechanical properties of Ag/Bi2223 composite superconductors
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Ag/Bi2223复合超导体的力学性能
DOI：
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发表时间：
2000
期刊：
影响因子：
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通讯作者：
Shojiro Ochiai
中科院分区：
文献类型：
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作者：
K. Osamura;M. Sugano;T. Wada;Shojiro Ochiai
研究了银包层Bi2223复合超导体的力学性能。由两个延性/脆性组分组成的复合材料呈现出三个阶段的行为：第一个名义弹性区域非常窄，随后应力-应变曲线的第一个微分逐渐减小。然后观察到第一个宏观应力变化，对应于氧化层的断裂。在塑性区，氧化层呈现多重断裂。宏观断裂应力估计分别为129和151 Mpa，在室温和77K下，用威布尔分布函数分析了多重断裂现象。尤其是断裂的最小应力远小于宏观断裂应力。结果表明，当施加拉伸载荷时，临界电流的退化与氧化层微裂纹的萌生直接相关。
Mechanical properties of silver sheathed Bi2223 composite superconductors have been studied. The composite consisting of two ductile/brittle components gives a three stage behavior The first nominal elastic region is very narrow and followed by a gradual decrease of the first differential of the stress -- strain curve. Then the first macroscopic stress change was observed, corresponding to the fracture of the oxide layer. In the plastic region, the oxide layer shows multiple fracture The macroscopic fracture stress was estimated to be 129 and 151 MPa, respectively at room temperature and 77 K The multiple cracking phenomenon was analyzed by using a Weibull distribution function. Especially the minimum stress to fracture was found to be much smaller than the macroscopic fracture stress. It is that the degradation of the critical current when applying a tensile load is related directly with initiation of microcrack in the oxide layer.