Broader Approach Agreement

During the implementation of the comprehensive approach and the addition of this agreement, further activities were carried out to validate the project developed as part of the agreement. The need for a neutron source for fusion materials research was recognized as early as the 1970s. Although neutrons have induced degradation similarities on a mechanistic approach, threshold energies for decisive transmutations are generally on the spectrum of fission neutrons. The production of he over 56Fe (n,α) 53Cr in future fusion reactors of about 12 appm/dpa will result in swelling and destructive materials. Existing neutron sources, i.e. fission reactors or spallation sources, result in different types of extraction, with extrapolation tests unsuccessful due to the lack of experimental observations in fusion reactor operating areas. Neutrons with a wide peak at 14 MeV can be produced with Li (d,xn) reactions; the technological efforts that began with the FMIT in the early 1980s have finally matured with the success of IFMIF/EVEDA as part of the broader conceptual agreement. The current state of the five technological challenges considered to be the most critical in the past is being addressed. This would be: 1) the feasibility of IFMIF accelerators, 2) the long-term stability of the lithium flow under the ifMIF nominal conditions; 3) potential instabilities in the lithium sieve induced by 2 × 5 MW deuteroonic radiation; 4) the uniformity of the temperature in the samples during irradiation and 5) the validity of the data with small samples. Other fusion material control ideas have been considered, but may not be technologically feasible if fixed objectives are taken into account, or it would be necessary for the results of a li (d.xn) installation to be reliably interpreted. In addition, we now know that IFMIF`s costs, which have been constantly estimated for decades, are marginal to the cost of a fusion reactor. The less ambitious performance of the DEMO reactor, considered to be envisaged, is correlated with a lower need for fusion neutron flows; Therefore, the IFMIF, with its two accelerators, might not be necessary, as a single accelerator, as proposed by the European DONES or the Japanese A-FNS, would meet the current needs > 10 dpa/fpy. The global fusion roadmap defines a fusion neutron source until the middle of the next decade, and the success of the IFMIF/EVEDA phase realizes this four-decade-old dream.