Magnesium vapor induced surface disruption of metal particles

Abstract

Compositions comprising magnesium nanoparticles, a nanoscale metal or metalloid, and an oxidizer and methods of fabrication the compositions are described. One example use of such compositions is in high energy fuel applications. One example method includes fabricating a composite by adding magnesium nanoparticles to a composition of a nanoscale metal or metalloid and an oxidant. Examples of the composition resulting from the described processes provides shorter burn times and a multi-fold increase in reactivity compared to the corresponding composition comprising the same amount of nanoscale metal or metalloid and oxidizer but without the magnesium nanoparticles.

We claim: 
     
         1 . A composition, comprising:
 magnesium nanoparticles;   a nanoscale metal or metalloid selected from the group consisting of boron, silicon, titanium, and aluminum; and   an oxidizer,   wherein the composition has a burn time reduced by about 50% to about 60% when compared to a second composition comprising the same amount of the oxidizer and the nanoscale metal or metalloid but without the magnesium nanoparticles.   
     
     
         2 . The composition of  claim 1 , wherein the oxidizer comprises the first oxide of the metal or metalloid. 
     
     
         3 . The composition of  claim 2 , wherein the first oxide of the metal or metalloid is a native oxide shell of the metal or metalloid. 
     
     
         4 . The composition of  claim 1 , wherein the oxidizer comprises one or more second oxides selected from the group consisting of CuO, B 2 O 3 , Al 2 O 3 , TiO 2 , and SiO 2 . 
     
     
         5 . The composition of  claim 1 , wherein the nanoscale metal or metalloid has an average particle size of about 390 nm to about 420 nm. 
     
     
         6 . The composition of  claim 1 , wherein the magnesium nanoparticles have an average particle size of about 350 nm to about 400 nm. 
     
     
         7 . The composition of  claim 1 , wherein the molar of the magnesium nanoparticles over the total molar of the magnesium nanoparticles and the nanoscale metal or metalloid is about 3.0% to about 15.0%. 
     
     
         8 . The composition of  claim 1 , wherein the molar ratio of the nanoscale metal or metalloid over the oxidizer is about +/−20% of the stoichiometric ratio. 
     
     
         9 . The composition of  claim 4 , wherein the molar ratio of the nanoscale metal or metalloid over the total molar of the one or more second oxides is about +/−20% of the stoichiometric ratio. 
     
     
         10 . The composition of  claim 1 , wherein the molar ratio of the oxidizer over the nanoscale metal or metalloid is about +/−20% of the stoichiometric ratio. 
     
     
         11 . The composition of  claim 4 , wherein the molar ratio of the total molar of the one or more second oxides over the nanoscale metal or metalloid id about +/−20% of the stoichiometric ratio. 
     
     
         12 . The composition of  claim 1 , wherein the weight percent of the nanoscale metal or metalloid of the total weight of the composition is about 9.0% to about 10.5%. 
     
     
         13 . The composition of  claim 1 , wherein the weight percent of the magnesium nanoparticles of the total weight of the composition is about 0.5% to about 4.0%. 
     
     
         14 . The composition of  claim 1 , wherein the peak pressure of the composition is increased by about 15% to about 30% over the peak pressure of the second composition. 
     
     
         15 . The composition of  claim 1 , wherein the pressurization rate of the composition is increased by about 5-fold to about 6-fold over the pressurization rate of the second composition. 
     
     
         16 . The composition of  claim 1 , wherein the composition has a burn time reduced by about 4.0 ms to about 5.0 ms over the burn time of the second composition. 
     
     
         17 . The composition of  claim 1 , wherein the composition has an ignition temperature lower than the ignition temperature of the second composition. 
     
     
         18 . The composition of  claim 1 , wherein the composition has an ignition temperature of about 500° C. to about 750° C. 
     
     
         19 . A method of fabricating the composition of  claim 1 , the method comprising:
 dispersing the magnesium nanoparticles, the nanoscale metal or metalloid; and   drying the first composition to provide the composition of  claim 1 .   
     
     
         20 . The method of  claim 19 , wherein the first solvent is an organic solvent that does not contain oxygen, or a mixture of multiple organic solvents that do not contain oxygen.