use for explosion aluminum powder
why aluminium powder as deoxidier will be more active than mg powder ?
there is three reason for that ,
1， the energy density is different , after burn aluminum powder the energy is 83.73kJ/cm^3, the mg is 44.21kJ/cm^3, so obviously is aluminium powder energy is double of magnesium powder .
the metal powder reaction speed depend on particle size ,therefore aluminium powder more fine size will have more advantage
2， production technology
magnesium powder cna be burn within nitrogen gas .
The preparation of propellant and energy grade aluminum powder is made by spray way .
aluminum powder production from high press spray aluminum liquid to be powder .
so aluminium powder have not react with , but for very fine size like 1-45um we will be production under the nitrogen gas system .
3， however if production magnesium powder , then can not use nitrogen gas , so normally magnesium powder production by grind way , so the particle size no way so smaller like aluminium powder
about the compatibility
Magnesium is more active than aluminum, and the compatibility of magnesium and aluminum with other substances is poor. Propellants, energy materials, these are all mixed systems of oxidizing and reducing agents, and we need something that's not as reactive, but that gives off a lot of energy, and aluminum is a good fit. For example, ammonium perchlorate mixed with aluminum powder is safer than ammonium perchlorate mixed with magnesium powder.
