High-heat-flux tests were carried out on 14 commercially available isotropic graphite samples manufactured by six Japanese companies. Graphite tiles of 25 × 25 × 1.0 mm3 were irradiated by an electron beam in an area of 18 mm diameter. The electron beam used was of low energy and high current, namely 40-50 V and 100-200 A, to simulate the near-surface deposition of energy. The beam was also defocussed to flatten the energy deposition profile through the irradiation area of 18 mm diameter. A computer simulation technique using the finite-element method was conducted to analyze the experimental results. Experimental results show that one sample which has some anisotropy revealed excellent resistance against high heat flux. Other graphite samples endured heat fluxes of 1-1.5 kW/cm2, irrespective of variation of their properties. Experimental results suggest that the ash content, the thermal expansion coefficient, and the mechanical strength may affect the resistance against the heat flux.
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Materials Science(all)
- Nuclear Energy and Engineering