Estimation of interfacial shear strength between superconducting oxides and silver sheath from multiple- fracture phenomenon of the oxide

The influences of interfacial shear strength between superconducting Y-Ba-Cu-O and silver and that between Bi-Pb-Sr-Ca-Cu-O and silver on the multiple fracture of the oxides embedded in silver-sheathed composite wires, prepared by a powder-in-tube method, on the multiple fracture of the oxides was analyzed. The stress distribution in the oxide was calculated based on the proposed method, and the multiple-fracture phenomenon was simulated by means of a Monte Carlo simulation method. From the comparison of the experimental results with those obtained by the simulation, the interfacial shear strength between Y-Ba-Cu-O and silver and that between Bi-Pb-Sr-Ca-Cu-O and silver were estimated to be nearly 30 and 40 MPa, respectively.