The use of pulsed beams for increasing radiation resistance of ceramics

摘要

Paper presents the results of a study of the applicability of pulsed C+/H+ (85/15) beams with a high current density for directional modification and hardening of the surface layer of AlN nitride ceramics. The purpose of the modification is to increase the radiation resistance to helium embrittlement and swelling as a result of the accumulation of helium in the surface layer. It has been established that an increase in the number of processing pulses leads to a sharp change in the morphology of surface layer, as well as a change in strength characteristics of ceramics. The sharp deterioration of strength characteristics is due to the presence in the structure of the surface layer of a high density of dislocations and defects, as well as the formation of microcracks as a result of pulsed processing with a large number of pulses. The effect of modification on the change in the structural characteristics of investigated samples has been established. It should be noted that these changes occur in a small surface layer with a thickness of not more than 0.5 mu m, which is most susceptible to degradation under irradiation and influence of corrosive media during practical use.