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The ITER toroidal field model coil is considered in terms of its manufacture, assembly and QA methods.

The cables and windings integrated in electric power devices require long high critical current density Bi-2223/Ag tapes. INFN, Europa Metalli and CISE SpA are jointly developing 100-meter-long silver-sheathed multifilamentary Bi-2223/Ag tapes through the powder-in-tube process. They also employ the react-and-wind method for the thermomechanical processing and winding of the tapes into double pancakes.

The granular and superconducting properties of silver-sheathed Bi-2223 tapes fabricated via the sequential pressing (SP) process were characterized. Specifically, scanning electron microscopic observations and transport measurements were carried out. The former validated the use of SP for producing long lengths of Bi-2223 tapes with similar microstructural characteristics as other pressed tapes. The latter revealed critical current densities of up to 14 kA/cm2 in the thin SP samples after a single cycle of pressing and heating.

The effect of Nb diffusion barriers on the magnetization properties of high performance Nb3Sn strands for the high field International Thermonuclear Experimental Reactor is studied via magnetization measurements. Results show that Nb diffusion barriers tend to increase hysteresis losses in the superconducting strands. On the other hand, the use of V leads to the formation of V3Sn which degrades the wires' critical current density.

The HIP 6.0 software is used to create a density-temperature deformation-mechanism map for analyzing the microstructure and transport critical current of cold rolled, cold uniaxially pressed and low load hot uniaxally pressed Ag-(Bi,Pb)2Sr2Ca2Cu3Ox tapes. Results show that the hot press samples increase in density as the annealing temperature increases. The data also show that the microcracks in the cold pressed samples are re-oriented.

The specifications of the NbTi/Cu cable for the superconducting dipole of the LHC are very demanding: [J.sub.c] (non Cu) in excess of 1000 A/[mm.sup.2] at 8 tesla and 4.2 K, with filament diameter of 5-6 microns. One type of cable is composed of 26 strands with a required critical current at 8 T and 4.2 K of 13,000 A and the other one has 40 strands with [I.sub.c] at 6 T and 4.2 K of 15,500 A. In this paper we describe the results we obtained in an extensive campaign of [I.sub.c] measurements carried out both on cables and on strands, these last both in virgin state and extracted from cable. The reliability of extrapolation from strands [I.sub.c] to cable performance is discussed as well as the degradation due to a cross-over in the cable thin edge.

The EU development effort for International Thermonuclear Experimental Toroidal Field (TF) and Central Solenoid (CS) Model Coils (MC) are reported. The EU's TFMC effort involves 4t of internal tin Nb3Sn cabling and strand and jacketing of 1 km TF conductor. For CSMC, 1200m of full size cable, 6.5t of bronze Nb3Sn strand and 5787m conductor jacketing are being produced. Developments and limitations of manufacturing processes are also discussed.

The design and fabrication of two types of Nb3Sn strands for the International Thermonuclear Experimental Reactor test coils are discussed. The first, which has specifications for high current densities and fabrication via the internal tin process, is currently under development at Italy's EM-LMI. The second, which has specifications for low hysteresis losses and fabrication via the bronze process, has already been developed and demonstrated by Germany's Vacuumschmelze.

Europa Metalli - LMI's contract with the International Thermonuclear Experimental Reactor (ITER) Organization to design and fabricate Nb3Sn superconducting strands via the internal tin process is discussed. The job entailed design modifications in response to changing specifications for high critical currents and low hysteresis losses. To date, current densities of 850 A/mm2 and hysteresis losses of 550 mJ/cm3 have been attained by the company.