The coating process of silica film on TiH₂ particles and gas release characteristic

The coating process of TiH₂ particles with SiO₂ layers, and the effect of the coating layer on gas release characteristic of TiH₂ powders were studied experimentally. The pH value of reactive solution and gelation rate of silicic acid are important factors for controlling surface morphologies of coating layers. When pH value is about 4.0 and concentration of silicic acid is about 0.5 mol/L, respectively, the condensation rate of silicic acid is appropriate for the formation of a homogeneous and dense coating membrane. The results of gas release at 700°C show that TiH₂ particles coated with silicon dioxide layers can efficiently delay the starting time of gas release of TiH₂ powders by 60-100s.