Prospects for the Use of Neutron-Shielding Metal Hydride Materials in the Construction of NPP Power Units

A technology has been proposed for increasing the thermal stability of titanium hydride by spraying metallic copper atoms onto its spherical granules. The method of quadrupole magnetron sputtering is used, which is based on low-temperature ion sputtering of a copper target on the surface of a metal hydride substrate. The microstructure of the surface of the modified fraction of titanium hydride is investigated. It is shown that the surface has a granular structure with a grain size of 25–50 nm. In some areas of the surface, grain alignment is observed in a specific direction, indicating a uniform texture of the applied copper surface layer. The metallized copper coating fills in surface defects and creates a shell that prevents thermal diffusion of hydrogen into the environment. The thickness of the deposited metallic copper on the surface of the shot is on average 400 nm. The phase composition of the surface layer of the samples of modified and unmodified hydride fraction is estimated by the method of electron probe analysis. It is shown that as a result of modification, the thermal stability of titanium hydride increases to 700 °C.