Chevrel 相PbMo_6S_8線材の内部応力の解析 : 実験結果との対比及びMgB_2線材との比較 Analysis of Internal Stress in Chevrel-phase PbMo_6S_8 Wires : Contrast with the Experimental Results and Comparison with MgB_2 Wires
The internal stress and residual strain of Chevrel-phase PbMo<sub>6</sub>S<sub>8</sub> wires were analyzed using an elastic-perfect plastic model. Comparing these results with those previously obtained from our experimental results, it was found that the order of size of the residual pre-strains qualitatively agrees with the experimental results except for part of the wires although the analyzed values were 0.2-0.4% larger than the experimental values. Concerning critical current (<i>I<sub>c</sub></i>) degradation in a small 3-layer PbMo<sub>6</sub>S<sub>8</sub> coil using a mandrel made of alumina, the difference between the experimental result and estimated value was argued. It was concluded that it is insufficient to explain the difference even when considering the effects of hoop's strain due to electromagnetic force and the variation in the cross-sectional area of the compound layer. Moreover, the internal stress and residual strain were analyzed for six kinds of assumed MgB<sub>2</sub> wire in which different sheaths were used. As a result, the wire with a Fe sheath had better mechanical characteristic than one with a Cu sheath in the case of using a single sheath. As for adopting composite sheaths, the wire with a Fe-barrier/Cu/Cu-Ni composite sheath had better strain characteristic as compared to the wire using a Nb-barrier/Cu/Cu-Ni sheath.
- 低温工学 = Journal of the Cryogenic Society of Japan
低温工学 = Journal of the Cryogenic Society of Japan 42(4), 102-107, 2007-04-25
CRYOGENICS AND SUPERCONDUCTIVITY SOCIETY OF JAPAN