Effect of silver concentration on electric and magnetic properties of HTS composites YBa2Cu3Ox–Ag

The resistive and magnetic properties of the composites YBa2Cu3Ox–Ag are investigated in a wide range of silver concentration (c = 0–100%). It is found that the concentration dependences of the critical temperature Tcz and the critical density Jc are nonmonotonic, the peak values being attained for c = 5–15 vol.% Ag. A quantitative and qualitative correlation between the Jc(c) and the concentration dependence Jcj(c) of the critical current density in the weak coupling subsystem of a granulated superconductor is established. It is shown that the variation of the critical parameters of granulated HTS compounds is associated with the formation of intergranular silver layers of various thickness.