Conceptual design of DEMO blanket materials test modules for A-FNS

A conceptual design of Advanced Fusion Neutron Source, A-FNS, has been conducted to achieve early realization of fusion-like neutron irradiation test for fusion reactor materials in Japan. A-FNS provides eight test modules to obtain irradiation data for fusion reactor materials. Conceptual design activities on Blanket Functional Materials Test Module (BFMTM), Tritium Release Test Module (TRTM) and Activated Corrosion Products Module (ACPM) were described among the A-FNS test modules. Also, basic concepts of the sub-system cells for the TRTM and the ACPM were also discussed

Preliminary Estimation of Tritium Migration for A-FNS Lithium Target System

In A-FNS, an accelerator-driven fusion-relevant neutron source, a few grams (3.5 g at full power operation) of tritium will be generated every year mainly in lithium target system. Since the generated tritium would migrate out of lithium target system, it is necessary to estimate the tritium migration in and out of the lithium target system for the design of detritiation systems for A-FNS, and therefore, a preliminary estimation is performed in the present study. As the results, it is found that almost all of the generated tritium in lithium target system would be trapped in impurity removal system, while less than 0.5% of that would migrate out. It is also indicated that the amount of tritium that would migrate out of lithium target system would be able to process with the existing techniques so far

Preliminary Estimation of Tritium Migration for A-FNS Lithium Target System

In A-FNS, an accelerator-driven fusion-relevant neutron source, a few grams (3.5 g at full power operation) of tritium will be generated every year mainly in lithium target system. Since the generated tritium would migrate out of lithium target system, it is necessary to estimate the tritium migration in and out of the lithium target system for the design of detritiation systems for A-FNS, and therefore, a preliminary estimation is performed in the present study. As the results, it is found that almost all of the generated tritium in lithium target system would be trapped in impurity removal system, while less than 0.5% of that would migrate out. It is also indicated that the amount of tritium that would migrate out of lithium target system would be able to process with the existing techniques so far.Technology of Fusion Energy (TOFE2020

Analysis of nitrogen distribution in iron-titanium alloys after nitrogen trapping in liquid lithium by using soft X-ray emission spectroscopy

Liquid lithium, a candidate material for the target of International Fusion Material Irradiation Facility (IFMIF), easily contains nitrogen. Nitrogen in liquid lithium should be removed as it accelerates corrosion of tubing materials. Hot trapping by iron-titanium alloys is expected to be a practical method. In order to understand the characteristics of nitrogen trapping with iron-titanium alloys in liquid lithium, nitrogen distribution was observed by Soft X-ray Emission Spectroscopy (SXES). Samples of Fe-5Ti alloys were immersed for 9–256 h in liquid lithium which contains 1000 w-ppm of nitrogen at 823 K and studied by X-ray Powder diffraction and SXES. The results show that nitrogen is trapped mainly in the grain boundaries and on the surfaces of the Fe-5Ti alloys and diffuses in Fe-5Ti much faster than in pure titanium. In addition, it is assumed that the amount of nitrogen trapping by the surface of Fe-5Ti alloys does not depend on the immersion time

Analysis of nitrogen distribution in iron-titanium alloys after nitrogen trapping in liquid lithium by using Soft X-ray Emission Spectroscopy

Liquid lithium, a candidate material for the target of International Fusion Material Irradiation Facility (IFMIF), easily contains nitrogen. Nitrogen in liquid lithium should be removed as it accelerates corrosion of tubing materials. Hot trapping by iron-titanium alloys is expected to be a practical method. In order to understand the characteristics of nitrogen trapping with iron-titanium alloys in liquid lithium, nitrogen distribution was observed by Soft X-ray Emission Spectroscopy (SXES). Samples of Fe-5Ti alloys were immersed for 9–256 hours in liquid lithium which contains 1000 w-ppm of nitrogen at 823 K and studied by X-ray Powder diffraction and SXES. The results show that nitrogen is trapped mainly in the grain boundaries and on the surfaces of the Fe-5Ti alloys and diffuses in Fe-5Ti much faster than in pure titanium. In addition, it is thought that the amount of nitrogen trapping by the surface of the alloys does not depend on the immersion time.31st Symposium on Fusion Technology (SOFT2020