Reaction of titanium beryllide with water vapor

摘要

Titanium beryllides such as Be_(12)Ti are considered to become promising alternatives of beryllium as the neutron multiplier. Thus, the authors investigated the reactivity of Be_(12)Ti with water vapor. In the experiments, the Be_(12)Ti sample was exposed to a gas containing water vapor of 10,000 ppm at the temperature of as high as 1000℃. Chaotic breakaway reactions were not observed for the Be_(12)Ti sample, and the amount of hydrogen generated was found to be lower in comparison with beryllium. Therefore, it can be said that titanium Be_(12)Ti has less reactivity with water vapor, which is a great merit for the neutron multiplier. In order to clarify the mechanism underlying the high tolerance to oxidation by water vapor, the authors observed the surface of the sample exposed to water vapor using digital electron microscope and scanning electron microscope. The results indicate that an oxidized layer was produced on the surface of the sample. Furthermore, X-ray diffraction analysis was carried out, which indicates that beryllium oxide (BeO) is present on the surface. However, the presence of titanium oxides or complex oxides of titanium and beryllium were not identified.