Blistering of mechanically polished molybdenum upon its exposure to deuterium-containing plasma

Recent data on the blistering process in polished polycrystalline Mo for the case of direct-current glow discharge in deuterium and D₂/2–4 mol % O₂ or N₂ admixtures, at an energy of incident molecular ions of 70–120 eV and a pressure of 14 Pa, are reported. Depending on the method of metal surface polishing, the initial metal grains are broken up into mutually disordered regions of smaller sizes (subgrains); the chemical composition of the damaged layer changes. In the formed structure, blistering can develop easily or be impeded. Small additions of O₂ or N₂ to deuterium facilitate the blistering.