Nbti Superconductors with Artificial Pinning Structures

A multifilament NbTi superconductor having continuous non-random pinning centers has been fabricated by mechanical metallurgy. Specifically, present state of the art wire processing was utilized to manufacture a superconductor with controlled, uniform, pinning centers and predetermined spacing which match the flux line lattice (FLL) continuously. This is accomplished by designing the superconductor filaments to form continuous pinning centers in layers (laminar pinning centers) with spacing being predetermined and related to the fluxoid lattice. The use of drawing and extrusion techniques combined with this design yields a practical superconductor. Preliminary current densities at low fields, significantly higher than in conventionally processed superconductors, have been measured.