In view of the recent interest in high Z materials as plasma facing materials, high heat load tests were performed on tungsten and tungsten containing alloys such as W-Re and Ta-W. The dimensions of the specimens were 20 mm Φ x 1-10 mm thickness. Heat loads were supplied by an electron beam testing apparatus. The low energy (40-50 eV) and high current (100-200 A) electron beam from the cathode hit the specimen surface in a duration of max. 40 s. After the tests, the damaged parts of the specimens were examined by stylus instrument and metallographically examined by using optical microscope and scanning electron microscope. Incubation time for erosion of the materials decreased with increase of their melting point. Crater-like damaged areas(eroded areas) were observed in all the materials, however, that of W-25% Re was the largest among them. In the damaged area, grains elongated from the fringe of the crater toward its center and also from the bottom of the crater toward the specimen bottom. There existed no visible cracks in the undamaged part of the specimens if their thicknesses were greater than 2 mm. The results were discussed in terms of microstructures and thermophysical properties of the materials.
ASJC Scopus subject areas
- Nuclear and High Energy Physics
- Materials Science(all)
- Nuclear Energy and Engineering