Nanocrystalline composites which contain specified level of nanoporosity are perspective materials for using as coatings for first wall of a thermonuclear reactor and also as a sorbent of active gases including hydrogen. At the present work the radiation stability of nanoporous V-N coatings obtained by ion-beam assisted deposition was investigated.
The initial structure of obtained V-N coating was nanocrystalline with the grain size 20-50 nm and surface area of pores 120 m2/g. The temperature resistant coefficient is negative. Annealing of such composites at 500oC during 2 hours doesn't lead to changes in structure and electroresistance.
It was shown that during irradiation by helium ions up to the doze 1.0-1.5x1017 ion/cm2 at 300oC the transforming of closed initial porosity into opened takes place. Specific surface of pores increases to 160 m2/g. Created branched porous structure promotes realising of surplus helium from coating and preservation its continuity.
In the case of irradiation of V-N coating by hydrogen ions to such dozes its influence on structure is less visible than the influence of helium. Visible transforming of porous initial structure takes place only after the doze 3x1017ion/cm2, which lies in small increasing of average size of intergranular pores. For investigation of structural radiation stability of nanoporous V-N coatings the doze of hydrogen irradiation was increased up to 1018 ion/cm2. Electronic microscopy of V-N composites didn't show destruction of the crystalline structure. Electroresistance of coatings was consistently increasing.
Obtained results show the good stability of nanoporous V-N coatings during irradiation by helium ions and their high catalytic characteristics relative to hydrogen.
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