Bi2223超导带材的机械性能的改善

Improving Mechanical Properties of Bi2223 Tapes

摘要:

通过在超导芯部引入Ag合金的方法制备了新结构单芯和多芯带材，并研究了此种带材机械性能，以及其相对于普通Bi-2223超导带材变化。这种新结构提高了Bi-2223超导带材抗拉伸应变的能力。在拉伸应力的作用下，单芯样品的屈服强度和σ0.2不可逆应变极限εirr和普通样品相比均有较大幅度的提高，其中的最大不可逆应变极限εirr约为0．32％，最大屈服强度σ0.2约为85MPa。多芯样品的最大不可逆应变极限εirr约为1．1％，最大屈服强度σ0.2约为160MPa。实验证明添加合金丝提高了纯银包套多芯带材的不可逆应变极限εirr，并减弱了临界电流的退化速度。但对合金包套的带材影响不大，这时合金包套对于带材的力学性能起主要作用。

Abstract:

A newly designed Bi2223 tape incorporating an Ag alloy wire in superconducting core is described. It is shown that the new structure considerably improves the superconducting properties of monofilament tapes. The maximum Ic is as high as 75 A, and Jc= 1.6104A/cm2 , increases of 30% over those of conventional superconductor tape. At the same time the mechanical properties of the new Bi2223 tape show considerable improvement.