Mechanical-electromagnetic property of stainless sheet laminated BSCCO-2223 wires

• Published in: Materials research express Vol. 6; no. 2; pp. 26001 - 26013
• Main Authors: Osamura, Kozo, Machiya, Shutaro, Kawasaki, Takuro, Harjo, Stefanus, Kato, Takeshi, Kobayashi, Shinichi, Osabe, Goro
• Format: Journal Article
• Language: English
• Published: IOP Publishing 09.11.2018
• Subjects: BSCCO-2223 Wire; critical current; mechanical property; reversible strain limit; superconducting composite; superconductor
• ISSN: 2053-1591; 2053-1591
• DOI: 10.1088/2053-1591/aaed0c

In order to elucidate the effect of applied tensile stress/strain on the critical current of DI-BSCCO-2223 wires, the critical current measurement and the tensile test were carried out at 77 K. Neutron diffraction measurements were also performed at 77 K to get direct information about the local strain exerted on the BSCCO superconducting filaments. It was reported that the critical current of BSCCO wires decreases linearly in a small range of tensile stress/strain and that the critical current returns reversibly on reducing the stress/strain. The gradual decrease of critical current was observed within the reversible region. When the tensile stress /strain increased beyond a characteristic value, the critical current decreased rapidly due to the brittle fracture of BSCCO filaments. It is proposed that the reversible stress/strain limit of critical current (Rrec and Arec) can be defined experimentally as the 99% Ic recovery stress (R99%rec) and strain (A99%rec). The reversible strain limit is proposed to consist mainly of three factors of pre-strain, thermal strain and tensile fracture strain of SC filaments themselves. The calculated relation between the Rrec and Arec could well explain quantitatively the observed relation between 99% Ic recovery stress and strain.