Mechanical Behaviours in Bi2223/Ag/Ag Alloy Composite Tape with Different Volume Fractions

Abstract

Bi2Cr2Ca2Cu3O x (Bi2223) composite tapes consisting of Bi2223 filaments, metal Ag and Ag alloy are usually exposed to a high magnetic field. The mechanical behaviour of composites is determined by the distribution and content of Bi2223 filaments in a magnetic field. Several Bi2223 composite tapes have different volume fractions of Bi2223 filaments, and the volume fraction is of fundamental importance in the determination of mechanical behaviour. In this paper, we present mechanical response to understand the effect of volume fraction of Bi2223 filaments. The critical current density is determined with consideration of the self field effect firstly. Then, the results of effective elastic moduli and mechanical stresses are presented based on the micromechanics approach. The mechanical response depends not only on the material properties but also on the Lorentz force. It is concluded from the computational results that the reduction of volume fraction of filaments can increase the mechanical stability, while the critical current density is decreased. Thus, it is necessary to consider both the mechanical limitation and requirement of the critical current of tape.