Stress/strain characteristics of Cu-alloy sheath MgB2 superconducting wires

Mechanical properties of MgB2superconducting wires fabricated by internal Mg diffusion process

“…One can point out that I c drop at > irr is too sharp. Similar steep I c drops were reported in literature published by Katagiri et al and Kováč et al [12][13][14][15][16]. In the present study, some specimens broke outside the pair of voltage taps, which were used for voltage monitoring.…”

“…In the reversible region, I c increases reversibly and linearly with increasing strain. Similar I c -strain results were found in literature published by Dhallé et al [11], Katagiri et al [12][13][14] and Kováč et al [15,16]. On the other hand, in the irreversible region, I c deteriorates irreversibly.…”

Mechanical and Superconducting Properties of NbTi Reinforced MgB₂ Wires

“…σ=BJR=5.6×107 Pa=56 MPa (2) The calculated hoop stress-56 Mpa was within the stress range corresponding to the strain of 0-0.2 %. And within this very small strain range, the wires current carrying abilities would decline only a little [10,21]. Here, the bending strain ε b was neglected, because εb was determined by ε b =r/(2R+r) [23], where r and R represent the radius of MgB 2 wire and the solenoid respectively.…”

“…K. Katagiri has used copper as sheath material and obtained the yield strength over 40 MPa [9]. Corresponding to the mechanical properties of Cu and Cu-alloy (Cu-Zr, Cu-Be and Cu-Cr) sheathed MgB 2 wires, the Cu-alloy sheath significantly increased the yield strength of the wires by over 100 MPa [10]. P. Kováč prepared Cu stabilized MgB 2 composite wires with an NbTi barrier and obtained effective mechanical reinforcement [11].…”