Hot explosive compaction of Mo-Ti alloys

The hot explosive compaction (HEC) technique developed for tungsten-titanium (W-Ti) alloys has been applied to molybdenum-titanium (Mo-Ti) alloys as well. The Mo + Ti powders were mixed and surrounded by an exothermic Ti + C mixture. The TiC reaction, when ignited, released a large amount of heat via a self-propagating high-temperature synthesis (SHS) reaction. Heat from the SHS reaction diffused into the Mo + Ti powder bed, causing the interior temperature to rise above 1500 degrees C. When the powder bed became isothermal, it was consolidated to high density by pressure waves generated by the detonation of an explosive. The amount of explosive charge and the molar ratio of exothermic mixture to sample were adjusted to produce full-density Mo-Ti alloy billets. The billets were sectioned and examined with scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction analysis (XRD), and microhardness measurements. In the context of the original fabrication process, the evolution of the resultant microstructure of the Mo-Ti product is described.