Ignition and Combustion Characteristic of B·Mg Alloy Powders

Boron and its alloys have been explored a lot and it is expected that they can replace pure aluminum powder in the energetic formulation of active materials. MgB₂ compounds were prepared and characterized by a combination of mechanical alloying and heat treatment. The ignition and combustion of boron-magnesium alloys were studied with the ignition wire method and laser ignition infrared temperature measurement. The results show that MgB₂ has good ignition characteristics with maximum ignition temperatures obtained by the two various methods of 1292 K and 1293 K, respectively. Compared with boron, the ignition temperature of MgB₂ is greatly reduced after alloying. The ignition reaction of MgB₂ mainly occurs on the surface and the ignition process has two stages. In the initial stage of ignition, the large flame morphology and combustion state are close to the combustion with gaseous Mg, whereas the subsequent combustion process is close to the combustion process of B. Compared with boron, the ignition temperature of MgB₂ is greatly reduced which suggests that MgB₂ may be used in gunpowder, propellant, explosives, and pyrotechnics due to its improved ignition performance.