The High Field Magnet Laboratory at the Radboud University Nijmegen is rapidly expanding its capabilities. The developments encompass both organizational changes and new possibilities for research. The organization of the HFML was strengthened as a consequence of stronger participation of the Foundation for Fundamental Research on Matter (FOM), and an increase of the core-funding. This change makes that HFML is now considered on a national level as large research facility that operates at an international scale. At the same time work is underway to build new and powerful magnets, and provide electromagnetic radiation for magneto-spectroscopic studies.Electromagnetic radiation in the infrared and far-infrared spectrum will soon be available in the HFML with wavelengths between 3 µm and 1.5 mm, produced by the 'FELIX' facility, comprising the long-wavelength free electron laser 'FLARE' that in September 2011 produced its first light and the free electron lasers that have been moved from Rijnhuizen to Nijmegen. In magnet technology great strides are made to make magnets available for the user community with unprecedented performance: late in 2012 we hope to commission a new all-resistive magnet system that will generate a steady magnetic field as high as 38 T, by fully exploiting the maximum power of the installation, i.e. 20 MW, and using all available improvements in the design and construction of 'Florida-Bitter' resistive magnets. We are also well underway with the design of a 45 T hybrid magnet system, using Nb 3 Sn superconductors and wind-and-react Cable-in-Conduit technology.

To extend its user's facilities, the High Field Magnet Laboratory (HFML-EMFL) at the Radboud University is in the process of building a 45-T hybrid magnet. The magnet system will consist of a 22 MW 32.7 T resistive insert and a 600-mmbore 12.3 T superconducting outsert magnet, and the design was significantly adjusted after a thorough design revision in 2011. The HFML hybrid magnet will be operated with separate current sources for the superconducting and resistive coils (20 kA at 10 V and 40 kA at up to 550 V, respectively). The outsert coil is a solenoid layer wound with all-Nb 3 Sn/Cu cable-in-conduit conductor (CICC), cooled by a forced flow of supercritical helium and operated at 20 kA. Similar to the series-connected hybrids for the HZB (Berlin, Germany) and the NHMFL (Tallahassee, FL, USA), the HFML outsert coil contains three grades of conductor. All CICC grades are based on high-current density Nb 3 Sn strand produced by Oxford Superconducting Technology. The CICC production and qualification program has been completed successfully. The coil will be wound at the NHMFL and, after heat treatment and impregnation, sent to Nijmegen for integration into the cryostat. In this paper, the design choices and current status of the program are presented. IndexTerms-CICC, high field magnet, Nb 3 Sn superconductivity. I. INTRODUCTIONT HE High Field Magnet Laboratory at the Radboud University Nijmegen (HFML, partner in the European Magnetic Field Laboratory, EMFL) is developing a 45 T hybrid magnet system, which will consist of a solenoidal 12.3 T Nb 3 Sn-CICC based superconducting outer magnet (outsert) and a 32.7 T Florida-Bitter type resistive inner magnet (insert) with a useful warm bore of 32 mm [1], [2]. After a thorough design review in

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The High Magnetic Field Laboratory in Nijmegen has been collaborating with the National High Magnetic Field Laboratory (NHMFL) in Florida on a 45 T hybrid magnet project. The primary scope of the collaboration was the design and manufacture of the hybrid magnet's superconducting cold mass. The 7.5 ton cold mass includes a single 13 T solenoid wound with high J C RRP Nb 3 Sn/Cu cable-in-conduit conductor. The coil will be forced flow supercritical helium and operated in parallel with a set of Bitterdisk resistive coils. Coil winding, reaction heat treatment, epoxy impregnation, and cold mass assembly has been completed at the NHMFL. The full cold mass has been delivered to Radboud University and will be assembled with the cryostat and interfaced with the system utilities.