Аңдатпа
This paper investigates the high-temperature corrosion of neutron-irradiated titanium beryllide B e 12 T i in a vapor-argon environment, emphasizing the kinetics of mass loss and the forms of released tritium. The experiments used a modified TGA-DSC 3 + synchronous thermal analysis system, which simultaneously records changes in sample mass and the radioactivity of tritium-containing compounds in exhaust gases. Two batches of samples, irradiated to 1.9 and 2.9 dpa, were examined at water vapor partial pressures of 10 and 2200 Pa over a temperature range up to 1273 K. Results show that the corrosion interaction between B e 12 T i and water vapor occurs in multiple stages. Up to about 575 K, initial mass loss occurs due to the removal of adsorbed moisture and drying of the defective porous structure, without tritium release. As heating continues to around 900 K, tritium is released, mainly in molecular forms ( HT + T 2 ), indicating escape from near-surface traps. Above 900 K, a stable corrosion regime is reached, characterized by the highest mass growth rate and the dominance of hydrous tritium forms ( HTO + T 2 O ). Kinetic analysis revealed that the activation energy of the high-temperature corrosion stage depends weakly on both neutron irradiation dose and water vapor partial pressure, indicating that a single rate-limiting step governs the process. The effects of environmental conditions and irradiation are primarily reflected through an increase in the pre-exponential factor. Samples irradiated up to 2.9 dpa showed earlier surface activation, a shift of the corrosion temperature front to lower temperatures, and more than a twofold increase in total tritium yield, due to a higher initial tritium production rate and improved defect-related tritium release channels. These results show that neutron irradiation does not change the core mechanism of high-temperature corrosion of B e 12 T i but significantly impacts its initiation conditions and progression, with direct implications for evaluating tritium behavior in beryllide materials used in fusion power systems.