Increase in Thermal Stability of HYDRIDE of the TITANIUM

Abstract

The paper presents the results of studies of the modification of the surface of a fraction of titanium hydride with borosiloxanes in order to increase its thermal stability at high temperatures and protect titanium from oxidation for possible use as a heat-resistant neutron-protective material in nuclear power engineering. A theoretical model has been developed for modifying a fraction of titanium hydride with borosilicate by sol-gel technology from aqueous solutions of sodium organosilicinate and boric acid. The technology for modifying titanium hydride consists in the preliminary chemical activation of the surface of the fraction by a silicone oligomer - sodium organosilicinate (OSN) followed by treatment with boric acid, separation of the solid phase of titanium hydride and subsequent drying at 100 ∘ C. During the synthesis of sodium borosilicate and its thermal treatment in the temperature range 100-500 ∘ C, complex structural-phase rearrangements were observed. At 100 ∘ C, an amorphous-crystalline silicate of CH 3 (Si 30.4 B 1.6 O 64 ) Na monoclinic syngony with large crystal lattice parameters was formed. The thermal treatment of the borosilicate coating at 300 ∘ C led to a change in the radiographic characteristics of the crystalline phase and the formation of a monoclinic NaBSi 2 O 5 (OH) 2 structure with continuous layers of silicon-oxygen tetrahedra. Further crystallization of borosilicate at a temperature of 500 ∘ C leads to the formation of a silicate of the skeleton type NaBSi 3 O 8 of triclinic syngony. Above 500 ∘ C, sodium borosilicate passes into a glassy state.