Interaction of transition metals and alloys with hydrogen in conventional SHS and radiation-assisted thermal explosion modes

SHS of hydrides in the metal-hydrogen, metal-intermetallic-hydrogen, metal-nonmetal-hydrogen systems is overviewed. To date, more than 200 hydrogen-rich hydrides, deuterides, and hydrogen-containing composite materials (carbohydrides and hydridonitrides of Ti, Zr, etc.) have been synthesized. Combustion of the Zr-Co, Zr-Ni, and Ti-Co intermetallics in hydrogen was found to proceed in the temperature range 120–300°C and yield intermetallide hydrides. The reaction root was found to depend on synthesis conditions. Described is radiation-induced thermal explosion (termed thermal-radiation process, TRS) in Me-H, Me-N-H, Me-C-H, Me-Me′-H, etc. systems as a new route to synthesis of hydrides. Hydridonitrides and carbonitrides of Group IV metals and their alloys, as well as hydrides of intermetallic compounds have been synthesized. An over-stoichiometric hafnium hydride, HfH2.42, was synthesized for the first time. A new phenomenon, cold synthesis of hydrides, was discovered.