New Energetic Solid Propellant Ingredients

Boron has significant potential as a high energy density ingredient in ramjet propellants and fuels. This is due to boron's high heat of combustion and low atomic weight. For a ramjet ducted rocket, theoretical volume specific impulses of 1600- 1800 sec g cm-3 have been reported for a fuel rich boron solid propellant, 45 % greater than the best hydrocarbon composition. Boron's high ignition temperature and surface oxide layer make it difficult to ignite and sustain combustion. Magnesium treating boron employing MACH I's proprietary reactive milling technology should improve the ignition and combustion characteristics and realize this potential. Magnesium will be present as a surface coating and penetrated into the bulk particle as magnesium-boron inter-metallic compounds. Magnesium readily ignites due to its lower ignition temperature vs. boron. It should also improve the combustion characteristics since magnesium will remove the boron oxide layer (which inhibits boron combustion) by reducing it to elemental boron. Ignition temperature and combustion properties will be studied as a function of magnesium level. Dr. Edward Dreizin of the New Jersey Institute of Technology will employ his previously developed hotwire ignition measurement technique and constant volume explosion apparatus. The minimum required magnesium level (maximum energy density) will be determined.