Fusion Science and Technology / Volume 4 / Number 3 / November 1983 / Pages 528-554
Special Section Contents / Radioactivation of Fusion Structures / dx.doi.org/10.13182/FST83-A22805
Articles are hosted by Taylor and Francis Online.
The potential problems of radioactivation in the materials surrounding a neutron-producing fusion plasma were identified over 8 yr ago. At the same time, the use of low activation materials such as graphite, silicon carbide (SiC), and aluminum alloys was proposed for the structural material in fusion power reactors as a way to greatly reduce the major problems of radioactivity resulting from the more conventional stainless steel materials. A brief review of the current status of the reasons for low activation fusion is presented. Design studies with the low activation materials are not covered here. The consequences of low activation fusion are compared with stainless steel fusion structures and it is found that the radioactivity after reactor shutdown, as measured in curies, may be reduced by a factor of 1 000 00O. Even then, this limit is determined by impurities in the materials rather than the low activation materials themselves. Problems from decay heat with potential meltdown are reduced for aluminum and completely eliminated for SiC and graphite. Contact or hands-on maintenance may be performed in regions immediately behind the blanket that otherwise require fully remote operations. Small amounts of radioactive waste materials may be stored in surface facilities for the low activation concept. This is compared to the conventional steel systems where high-level radwaste geologic storage facilities may be required. Preliminary projected incremental costs for low activation fusion do not appear excessive but cost/benefit analyses are needed to evaluate the optimum degree of activation reduction. Low activation fusion can help assure the full potential of fusion in providing an environmentally benign energy source with a high degree of safety and public acceptance.