Thermal-radiation processes in the MeIV-H system. Synthesis of hydrides of metals

A special hermetic chamber was elaborated and constructed to treat materials by the electron beam in vacuum and in hydrogen atmosphere (P-H = 1-2 atm; 1 atm = 10 1325 Pa). The investigation was carried out on the high current electron accelerator LAE-5 using a focused electron beam. The system of temperature measurement during irradiation was developed. It allowed measurement of the thermal effects taking place under the action of irradiation, and the establishment of the main features of thermal-radiation processes in the Me-H system. As a result of experiments at different doses and power of dose (0.025-1 MRad/s) in vacuum and in the hydrogen atmosphere, the main peculiarities of the processes have been observed, such as: (i) the thermal-radiation synthesis of hydrides of IV group metals of stoichiometric composition - TiH2, ZrH2, and HfH2; (ii) the phenomenon of 'cold synthesis' of hydrides. As a result of this phenomenon hafnium hydride of super-stoichiometric composition, HfH2.4, has been obtained. (C) 2002 Elsevier Science BY All rights reserved.