Speaker
Hiroyasu Tanigawa
(Department of Fusion Reactor Materials Research)
Description
F82H is the reduced activation ferritc/martensitic (RAFM) steel which has been developed in Japan. Its chemical composition was designed based on the composition of high Cr heat resistant steel, Mod9Cr-1Mo, reducing activity level by replacing Mo to W, Nb to Ta, and reduce N level to suppress 14C formation.
In order to prove its potential as the structural materials, it is critical to provide data of various properties in accordance with the requirements defined in the existing design code. Database preparation status was assessed by referring to the dataset provided to define Mod9Cr-1Mo in ASME and RCC-MRx. It was pointed out that some physical properties were not sufficiently evaluated, and some gaps in the dataset of the major mechanical properties were identified even though the majority of it fulfils the requirements.
On the other hand, the gap analyses indicated that there are numerous undefined properties and fabrication technologies in the existing design code in view of fusion DEMO application. The magnetic properties are the essential properties to evaluate the impact of plasma disruption on the blanket structure, but no definition was found in the existing design code. HIP joining is selected as the candidate method to fabricate the breeding blanket first wall with cooling channels, but no standard is available for HIP joining method to use it for highly pressurized structure.
Irradiation effects have been recognised as the potential risks for securing the structural integrity for the lifetime of the fusion blanket system. Thus, the irradiation database has been accumulated for various properties, but the number and quality of the data is limited because of the lack of fusion neutron source, irradiation volume and the standard for small specimen testing method. The design rules also need to be developed to compromise those degradation of properties due to irradiation.
Co-authors
Hideo Sakasegawa
(Department of Fusion Reactor Materials Research, Japan Atomic Energy Agency, Aomori, Japan)
Hiroyasu Tanigawa
(Department of Fusion Reactor Materials Research, Japan Atomic Energy Agency, Aomori, Japan)
Takanori Hirose
(Department of Fusion Reactor Materials Research, Japan Atomic Energy Agency, Aomori, Japan;Department of Fusion Reactor Materials Research, Japan Atomic Energy Agency, Aomori, Japan)
Takeshi MIyazawa
(Department of Fusion Reactor Materials Research, Japan Atomic Energy Agency, Aomori, Japan;Department of Fusion Reactor Materials Research, Japan Atomic Energy Agency, Aomori, Japan)