Can I use any other metal besides aluminum? What about magnesium or magnalium?
Both magnesium and magnalium (a 50/50 blend of Mg and Al) powders have been tested instead of aluminum, and both worked just fine at 325 mesh. If you can't get 325 mesh Al powder, substituting 325 mesh Mg powder or 325 mesh Mg/Al powder is acceptable, and performance is nearly identical.
You WILL need to adjust the mixture ratios to achieve a stoichiometric mixture, as the atomic weight of Mg is different than Al, and the reaction product (MgO instead of Al2O3) is different, as well.
|Metal||Mass Ratio (CuO : Metal)|
|Aluminum||4.422 : 1|
|Magnesium||3.273 : 1|
|Magnalium (50/50 Mg/Al)||3.847 : 1|
Just to reiterate a point made elsewhere: DO NOT USE METALS FINER THAN 400 MESH. 325 MESH IS OPTIMUM. Whe you use finer metals, the resulting mixtures burn far too fast to be useful as motor igniters, and may be much more sensitive to accidental ignition.