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Activities under the EURO fusion work package JET3 programme have been established to enable the technological exploitation of the planned JET experiments over the next few years, which culminates in a D-T experimental campaign, DTE-2. In the areas of nuclear technology and nuclear safety the programme offers a unique opportunity to provide experimental data that is relevant to ITER. The key purpose of the collected data will be to support bench marking and validation activities relating to neutronics and activation codes, and associated nuclear data, that are used to predict the nuclear behavior of ITER component and materials, during and after operations. This paper details the status and key issues of the ongoing ACT sub-project under work package JET3, which aims to take advantage of the large 14 MeV neutron fluence expected during JET DTE-2 to irradiate samples of real ITER materials used in the manufacturing of the main in-vessel tokamak components. The materials considered, with specified minor elemental impurity levels, include: Nb3Sn, SS316L steels from a range of manufacturers, SS304B, Alloy 660, W, CuCrZr, OF-Cu, XM-19, Al bronze, NbTi and EUROFER. The activities include provision for measurement of nuclide activities for each material and comparison against the predicted quantities through calculation with the FISPACT-II inventory code. Included here are key pre-analysis results for the selected ITER irradiation samples, and corresponding optimization of dosimetry foils (Ti, Mn, Co, Ni, Y, Fe, Co, Sc, Ta) that will be irradiated at selected positions inside JET irradiation stations in order to determine the neutron spectrum. Preliminary experimental activation results through recent JET D–D operations are discussed.

This paper details progress in experimental characterisation work at JET for the long-term irradiation station, conducted as part of a project to perform activation experiments using ITER materials. The aim is to take advantage of the significant 14 MeV neutron yield expected during JET operations to irradiate samples of materials that will be used in the manufacturing of ITER tokamak components, such as Nb3Sn, SS316L steels from a range of manufacturers, SS304B, Alloy 660, W, CuCrZr, OF-Cu, XM-19, Al bronze, NbTi and EUROFER. This paper presents an assessment of the nuclear environment at the relevant irradiation locations at JET, measured using a range of high purity dosimetry foils: Ti, Ni, Y, Fe, Co, Sc, and Ta, irradiated with fusion neutrons at JET over a period of 15 months. Experimental results are presented and compared to simulation predictions using a JET MCNP model coupled with the FISPACT-II inventory code. Comparisons are made for a total of 11 nuclear reactions using a range of nuclear data libraries in calculations. © EURATOM 2018.