Influence of Gaseous Environment on Reaction Behavior and Phase Formation in Ti/2B Reactive Multilayer Foils

Abstract

The effects of surrounding gaseous environment on the reaction behaviors and product formation for sputter-deposited Ti/2B reactive multilayers are reported. With the surrounding environment set to different air pressures, from atmospheric conditions to 10 -4 Torr, Ti/2B samples were reacted in a self-propagating mode, and the average reaction wave velocities were determined through high-speed imaging. Propagation speeds for 3.0 μm-thick multilayers were in the range of 10.89 to 0.05 m/s depending on bilayer thickness (i.e., reactant layer periodicity) and ambient pressure. X-ray diffraction analysis showed that single-phase TiB 2 forms within multilayers that have small bilayer thickness. Multilayers that have a large bilayer thickness developed a mixture of TiB 2 , TiB and TiO 2 .