On the electrical properties under irradiation of porous SiC prepared by sacrificial template technique

摘要

Flow Channel Inserts are the key elements in the DCLL breeder blanket concept for the required electrical insulation to reduce magnetohydrodynamic effects. Porous SiC materials produced for this purpose by a novel and inexpensive method which allows one to obtain different porosity percentage and physical properties are characterized regarding electrical conductivity and considering radiation effects. Insulating properties are verified before, during, and after 1.8 MeV electrons up to 140 MGy. Results indicate good stability under high temperature, and fusion-relevant ionizing radiation dose rates. However, enhanced electrical conductivity is observed when a corrosion and permeation-protective dense SiC layer is deposited onto the samples by chemical vapor deposition. Elemental analyses show differences in the impurity content and distribution which may be responsible for the electrical conductivity increase.