| dc.description |
Artificial pinning-centre (APC) niobium-titanium composites attain critical current density J<sub>c</sub> values higher than 4000 A mm<sup>-2</sup> at 5 T, 4.2 K, surpassing the barrier reached by the conventional Nb-Ti composite process. At 2 T APC composites achieve more than double the J<sub>c</sub> of conventional composites, making them particularly well suited for low-field applications. On the other hand, APC composites are inferior to conventional composites at 8 T, due to weak high-field pinning and reduced upper critical field. This review discusses fabrication techniques, microstructural development and superconducting and flux-pinning properties of APC composites. Key elements and underlying issues for achieving higher J<sub>c</sub> are identified and discussed in terms of the current state of the art. |
