Blistering of rhenium irradiated with 21keV helium ions

This paper describes blistering of rhenium following 21 keV He⁺-ion irradiation at temperatures between 300 K and 1200 K. Blistering starts at 300 K at a dose of 3×10¹⁷ ions/cm². The most probable blister diameter varies from 4400 ? at 300 K to 10100 ? at 1200 K. The blister depth τ _bl , the blister diameter φ _bl and the blister heighth _bi show a distribution. From the observations one could derive the following relationships:h _bl = 0.35φ _bl ; τ _bl =3.43φ _bl ^2/3 . The erosion yieldE _y due to blistering is function of doseE _y =0.51 atoms/ion at 3×10¹⁷ ions/cm²,E _y =0.56 atoms/ion at 6×10¹⁷ ions/cm² andE _y =0.14 atoms/ion at 3×10¹⁸ ions/cm². The sputtering yieldS (21 keV) is estimated to be ∼0.1 atom/ion. The corresponding surface regression is 44? at 3×10¹⁷ ions/cm² and 1323 ? at 9×10¹⁸ ions/cm². Surface regression has therefore little influence on the observations at low doses. Work performed at the Mathematicals Science Department of S.C.K./C.E.N. at Mol (Belgium)