Surface roughening and grain orientation dependence of the erosion of polycrystalline stainless steel by hydrogen irradiation

摘要

Surface roughening of polycrystalline stainless steel mirrors due to hydrogen bombardment was studied as a function of ion fluence and energy (1-4.3 x 10(14) H/m(2), 300-1500 eV/H). A strong micro-relief (100 nm scale) on single grains and a strong variation of the erosion depth between different grains were observed by scanning electron microscopy (SEM). A broad variation of the in-grain micro-relief was found to be independent of impact energy. The sputtering yield (Y) depends on the grain orientation, varying by a factor of about 2 for all impact energies. The correlation between surface morphology and orientation of the single grains was investigated using electron back-scattering diffraction (EBSD). Grains with nearly (111) surface orientation do not show any significant in-grain micro-relief, although they have nearly the highest Y. For other orientations close to low indexed surfaces, e.g., (311), no correlation was found between Y and roughness. (C) 2004 Elsevier B.V. All rights reserved.