This paper describes the properties of SC cable with natural oxide on the strands developed for the UNK SC magnets and summarizes the performance of short and long magnets made of such cable. The coating was selected based on the studies of cable samples with various strand coating. Ten 1-m long dipoles and two 6-m long dipoles were manufactured using the cable with natural oxide coating of strands. These dipoles had low value of AC losses in the coil and reached the maximum magnetic field of 6.5 T in magnet aperture at the current ramp rates up to 0.8 T/s and 4.25 K temperature. The effects of interlayer splices and cable electrical insulation on the magnet ramp rate dependence are also reported.

A current leads based on Bi-2223 HTS tapes for LHC SC magnets are optimised. Three current leads were manufactured for development of current leads and HTS tape design. The economical current leads design satisfy- ing the requirements of the technical specification for prototype 600 A HTS current leads is found.

The structure of a dipole magnet with an iron yoke, where the winding is made of a Bi-2223 high-temperature superconductor, has been developed and the magnet has been built at the Institute of High-Energy Physics. The magnet has also been tested. A magnetic field 0.9 T has been attained in the aperture at temperature 65 K and 1.9 T at 4.2 K. The special features of the magnet structure are described and the results of testing of the magnet in a submerged cryostat at different temperatures are presented.

Bi-2223 tapes with Ag-1 at.% Au and Ag-10 at.% Au matrices were fabricated for superconducting magnet current leads. The dependence of critical current on both temperature and magnetic field was studied. Electrical resistance, thermal conductivity, heat capacity and thermal contraction of the (Ag+Au) alloy matrix and HTS tapes were measured. Mechanical characteristics of HTS tapes at 77 K are presented.