Heavy metal free, environmentally green percussion primer and ordnance and systems incorporating same

Abstract

A sensitized explosive that comprises an explosive precipitated onto a sensitizer. The explosive is CL-20, PETN, RDX, HMX, or mixtures thereof and the sensitizer is aluminum, titanium, zirconium, magnesium, melamine, styrene, lithium aluminum hydride, or mixtures thereof. The sensitized explosive is used in a percussion primer that includes a bismuth compound and a melt binder. The bismuth compound is bismuth oxide, bismuth subnitrate, bismuth tetroxide, bismuth sulfide, or mixtures thereof and the melt binder is a wax having a melting point above ambient temperature, trinitrotoluene, poly(3,3-bis(azidomethyl)oxetane), poly(3-azidomethyl-3-methyloxetane), ethyl-3,5-dinitrobenzoate, or mixtures thereof. A gun cartridge and other primer-containing ordnance assemblies employing the percussion primer are also disclosed. Methods of forming the sensitized explosive and the percussion primer are also disclosed.

1 . A sensitized explosive comprising an explosive selected from the group consisting of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0 5,9 0 3,11 ]-dodecane (“CL-20”), pentaerythritol tetranitrate (“PETN”), cyclo-1,3,5-trimethylene-2,4,6-trinitramine (“RDX”), cyclotetramethylene tetranitramine (“HMX”), and mixtures thereof and a sensitizer selected from the group consisting of aluminum, aluminum oxide, titanium, zirconium, magnesium, boron, silicon, melamine, styrene, lithium aluminum hydride, calcium silicide, and mixtures thereof, wherein the explosive is precipitated onto the sensitizer.  
     
     
         2 . The sensitized explosive of  claim 1 , wherein the sensitized explosive has an average particle size that ranges from approximately 1 μm to approximately 100 μm.  
     
     
         3 . The sensitized explosive of  claim 1 , wherein the explosive comprises from approximately 70% by weight to approximately 99.5% by weight of a total weight of the sensitized explosive and the sensitizer comprises from approximately 0.5% by weight to approximately 30% by weight of the total weight of the sensitized explosive.  
     
     
         4 . A percussion primer comprising a sensitized explosive, a bismuth compound, and a melt binder, wherein the sensitized explosive comprises an explosive precipitated onto a sensitizer.  
     
     
         5 . The percussion primer of  claim 4 , wherein the explosive has an impact sensitivity that ranges from approximately 0.3 kp m to approximately 0.75 kp m.  
     
     
         6 . The percussion primer of  claim 4 , wherein the explosive is selected from the group consisting of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0 5,9 0 3,11 ]-dodecane (“CL-20”), pentaerythritol tetranitrate (“PETN”), cyclo-1,3,5-trimethylene-2,4,6-trinitramine (“RDX”), cyclotetramethylene tetranitramine (“HMX”), and mixtures thereof.  
     
     
         7 . The percussion primer of  claim 4 , wherein the sensitizer is selected from the group consisting of aluminum, aluminum oxide, titanium, zirconium, magnesium, boron, silicon, melamine, styrene, lithium aluminum hydride, calcium silicide, and mixtures thereof.  
     
     
         8 . The percussion primer of  claim 4 , wherein the sensitizer has a particle size that ranges from approximately 0.1 μm to approximately 100 μm.  
     
     
         9 . The percussion primer of  claim 4 , wherein the sensitizer has a particle size that ranges from approximately 100 nm to approximately 600 nm.  
     
     
         10 . The percussion primer of  claim 4 , wherein the sensitizer has a particle size that ranges from approximately 2 μm to approximately 5 μm.  
     
     
         11 . The percussion primer of  claim 4 , wherein the explosive comprises from approximately 70% by weight to approximately 99.5% by weight of a total weight of the sensitized explosive and the sensitizer comprises from approximately 0.5% by weight to approximately 30% by weight of the total weight of the sensitized explosive.  
     
     
         12 . The percussion primer of  claim 4 , wherein the bismuth compound comprises bismuth oxide, bismuth subnitrate, bismuth tetroxide, bismuth sulfide, or mixtures thereof.  
     
     
         13 . The percussion primer of  claim 4 , wherein the melt binder comprises a wax having a melting point above ambient temperature, trinitrotoluene, poly(3,3-bis(azidomethyl)oxetane), poly(3-azidomethyl-3-methyloxetane), ethyl-3,5-dinitrobenzoate, 1,3,3-trinitroazetine, natural gums, or mixtures thereof.  
     
     
         14 . The percussion primer of  claim 4 , wherein the sensitized explosive comprises from approximately 35% by weight to approximately 55% by weight of a total weight of the percussion primer, the bismuth compound comprises from approximately 20% by weight to approximately 75% by weight of the total weight of the percussion primer, and the melt binder comprises from approximately 0.5% by weight to less than approximately 20% by weight of the total weight of the percussion primer.  
     
     
         15 . The percussion primer of  claim 4 , further comprising at least one of ground glass, nitrocellulose, and tetracene.  
     
     
         16 . A percussion primer, comprising: 
 a sensitized explosive comprising an explosive selected from the group consisting of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0 5,9 0 3,11 ]-dodecane (“CL-20”), pentaerythritol tetranitrate (“PETN”), cyclo-1,3,5-trimethylene-2,4,6-trinitramine (“RDX”), and cyclotetramethylene tetranitramine (“HMX”) and a sensitizer selected from the group consisting of aluminum and melamine;    a bismuth compound selected from the group consisting of bismuth oxide, bismuth subnitrate, bismuth tetroxide, bismuth sulfide, and mixtures thereof; and    a melt binder selected from the group consisting of a wax having a melting point above ambient temperature, trinitrotoluene, poly(3,3-bis(azidomethyl)oxetane), poly(3-azidomethyl-3-methyloxetane), ethyl-3,5-dinitrobenzoate, 1,3,3-trinitroazetine, natural gums, and mixtures thereof.    
     
     
         17 . The percussion primer of  claim 16 , wherein the sensitized explosive comprises from approximately 35% by weight to approximately 55% by weight of a total weight of the percussion primer, the bismuth compound comprises from approximately 20% by weight to approximately 75% by weight of the total weight of the percussion primer, and the melt binder comprises from approximately 0.5% by weight to less than approximately 20% by weight of the total weight of the percussion primer.  
     
     
         18 . The percussion primer of  claim 16 , further comprising at least one of ground glass, nitrocellulose, and tetracene.  
     
     
         19 . A method of preparing a sensitized explosive, comprising: 
 precipitating an explosive onto a sensitizer, wherein the explosive is selected from the group consisting of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0 5,9 0 3,11 ]-dodecane (“CL-20”), pentaerythritol tetranitrate (“PETN”), cyclo-1,3,5-trimethylene-2,4,6-trinitramine (“RDX”), and cyclotetramethylene tetranitramine (“HMX”) and the sensitizer is selected from the group consisting of aluminum, aluminum oxide, titanium, zirconium, magnesium, boron, silicon, melamine, styrene, lithium aluminum hydride, calcium silicide, and mixtures thereof.    
     
     
         20 . The method of  claim 19 , wherein precipitating an explosive onto a sensitizer comprises dissolving the explosive in a solvent, adding the sensitizer to the solvent, and removing the solvent.  
     
     
         21 . The method of  claim 20 , wherein dissolving the explosive in a solvent comprises dissolving the explosive in a polar organic solvent selected from the group consisting of ethyl acetate, acetone, and mixtures thereof.  
     
     
         22 . The method of  claim 20 , wherein removing the solvent comprises forming crystals of the sensitized explosive.  
     
     
         23 . The method of  claim 22 , wherein forming crystals of the sensitized explosive comprises forming crystals of the sensitized explosive having an average particle size that ranges from approximately 1.0 μm to approximately 100 μm.  
     
     
         24 . A method of forming a percussion primer, comprising: 
 providing a sensitized explosive that comprises an explosive precipitated onto a sensitizer; and    combining the sensitized explosive with a bismuth compound and a melt binder.    
     
     
         25 . The method of  claim 24 , wherein providing a sensitized explosive that comprises an explosive precipitated onto a sensitizer comprises dissolving the explosive in a solvent, adding the sensitizer to the solvent, and removing the solvent.  
     
     
         26 . The method of  claim 25 , wherein dissolving the explosive in a solvent comprises dissolving the explosive in a nonpolar, organic solvent selected from the group consisting of ethyl acetate, acetone, and mixtures thereof.  
     
     
         27 . The method of  claim 24 , wherein removing the solvent comprises forming crystals of the sensitized explosive.  
     
     
         28 . The method of  claim 24 , wherein combining the sensitized explosive with a bismuth compound and a melt binder comprises combining the sensitized explosive with a bismuth compound selected from the group consisting of bismuth oxide, bismuth subnitrate, bismuth tetroxide, bismuth sulfide, and mixtures thereof.  
     
     
         29 . The method of  claim 24 , wherein combining the sensitized explosive with a bismuth compound and a melt binder comprises combining the sensitized explosive with a melt binder selected from the group consisting of a wax having a melting point above ambient temperature, trinitrotoluene, poly(3,3-bis(azidomethyl)oxetane), poly(3-azidomethyl-3-methyloxetane), ethyl-3,5-dinitrobenzoate, 1,3,3-trinitroazetine, natural gums, and mixtures thereof.  
     
     
         30 . A gun cartridge comprising: 
 a casing housing a percussion primer and a secondary explosive composition, wherein the percussion primer comprises a sensitized explosive, a bismuth compound, and a melt binder, the sensitized explosive comprising an explosive precipitated onto a sensitizer; and    a projectile disposed in a mouth of the casing.    
     
     
         31 . The gun cartridge of  claim 30 , wherein the explosive is selected from the group consisting of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0 5,9 0 3,11 ]-dodecane (“CL-20”), pentaerythritol tetranitrate (“PETN”), cyclo-1,3,5-trimethylene-2,4,6-trinitramine (“RDX”), cyclotetramethylene tetranitramine (“HMX”), and mixtures thereof and the sensitizer is selected from the group consisting of aluminum, aluminum oxide, titanium, zirconium, magnesium, boron, silicon, melamine, styrene, lithium aluminum hydride, calcium silicide, and mixtures thereof.  
     
     
         32 . The gun cartridge of  claim 30 , wherein the bismuth compound comprises bismuth oxide, bismuth subnitrate, bismuth tetroxide, or mixtures thereof and the melt binder comprises a wax having a melting point above ambient temperature, trinitrotoluene, poly(3,3-bis(azidomethyl)oxetane), poly(3-azidomethyl-3-methyloxetane), ethyl-3,5-dinitrobenzoate, 1,3,3-trinitroazetine, natural gums, or mixtures thereof.  
     
     
         33 . The gun cartridge of  claim 30 , wherein the gun cartridge comprises a centerfire gun cartridge.  
     
     
         34 . The gun cartridge of  claim 30 , wherein the gun cartridge comprises a rimfire gun cartridge.  
     
     
         35 . A primer-containing ordnance assembly, comprising: 
 a housing comprising a percussion primer and at least a secondary explosive composition, wherein the percussion primer comprises a sensitized explosive, a bismuth compound, and a melt binder, the sensitized explosive comprising an explosive precipitated onto a sensitizer.    
     
     
         36 . The ordnance of  claim 35 , wherein the explosive is selected from the group consisting of 2,4,6,8,10,12-hexanitro-2,4,6,8,10,12-hexaazatetracyclo[5.5.0.0 5,9 0 3,11 ]-dodecane (“CL-20”), pentaerythritol tetranitrate (“PETN”), cyclo-1,3,5-trimethylene-2,4,6-trinitramine (“RDX”), cyclotetramethylene tetranitramine (“HMX”), and mixtures thereof and the sensitizer is selected from the group consisting of aluminum, aluminum oxide, titanium, zirconium, magnesium, boron, silicon, melamine, styrene, lithium aluminum hydride, calcium silicide, and mixtures thereof.  
     
     
         37 . The ordnance of  claim 35 , wherein the bismuth compound comprises bismuth oxide, bismuth subnitrate, bismuth tetroxide, bismuth sulfide, or mixtures thereof and the melt binder comprises a wax having a melting point above ambient temperature, trinitrotoluene, poly(3,3-bis(azidomethyl)oxetane), poly(3-azidomethyl-3-methyloxetane), ethyl-3,5-dinitrobenzoate, 1,3,3-trinitroazetine, natural gums, or mixtures thereof.  
     
     
         38 . The ordnance of  claim 35 , wherein the ordnance comprises a grenade, mortar, detcord initiator, mortar round, or rocket motor.