Division of accelerators, cryogenics and magnetism

After the validation of the last superconducting toroidal field coils, the CEA's contribution to the construction of the Japanese JT-60SA Tokamak, dedicated to the study of nuclear fusion, is nearing completion. Ten of them (out of twenty) were manufactured under the responsibility of the CEA by GE Power in Belfort. These coils of nearly 16 tons each will fly to Naka in mid-February to join their sisters and integrate the structure of the Japanese Tokamak. These essential components for the Japanese fusion device are part of the International Thermonuclear Experimental Reactor (ITER) extended approach project, an international project for a civil nuclear fusion research reactor currently being built at Cadarache (Bouches-du-Rhône).

The first test campaign of the NOUGAT high field magnet was successfully carried out at the CNRS LNCMI Grenoble. This laboratory wishes to build a 30-tesla magnet by assembling a resistive magnet from LNCMI and a superconducting magnet designed by IRFU based on high temperature superconducting materials. To date, the field reached 20.8 T, including 12.8 T generated by the superconducting magnet alone. This is a decisive step towards NOUGAT's 30 T operating point and the validation of MI (Metal-as-Insulation) winding technology, where traditional insulation is replaced by metal co-insulation, developed in the DACM's Superconducting Magnet (LEAS) Laboratory.
The DACM is involved in several high-field magnet projects including medical (MRI) and large test stations (such as the hybrid magnet LNCMI at 43T). To obtain high field values, it is necessary to use new generation high temperature superconductors (HTS) instead of NbTi or Nb3Sn. The department's HTS R&D is studying ways of producing such magnets and solving the problems inherent in these conductors at these high field values (thesis by G. Dilasser[1], thesis by M. ALHarake[2], internal R&D for non-insulated windings...).

1] Experimental and numerical study of shielding currents in REBCO high temperature superconducting magnets, thesis defended in 2017, G. Dilasser
2] Contribution to the study of a high field magnet 30-40 T, thesis in progress, Dr. ALHArake