Methods and systems for electrophoretic deposition of energetic materials and compositions thereof

• US 10,358,737 B2
• Filed: 05/13/2015
• Issued: 07/23/2019
• Est. Priority Date: 08/08/2011
• Status: Active Grant

• Current Assignee: Lawrence Livermore National Security LLC (Government of the United States of America)
• Original Assignee: Lawrence Livermore National Security LLC (Government of the United States of America)
• Inventors: Sullivan, Kyle, Gash, Alexander E., Kuntz, Joshua, Worsley, Marcus A.
• Primary Examiner(s): Felton, Aileen B
• Application Number:
  US14/711,729
• Publication Number:
  US 20150252489A1
• Time in Patent Office: 1,532 Days
• CPC Class Codes: C06B 21/0083 Treatment of solid structures, e.g. for coating or impregnating with a modifier compositions therefor C06B23/00
• CPC Class Codes: C06B 45/14 a layer or zone containing an inorganic explosive or an inorganic explosive or an inorganic thermic component
• CPC Class Codes: C25D 13/12 characterised by the article coated
• CPC Class Codes: C25D 13/18 using modulated, pulsed, or reversing current
• CPC Class Codes: C25D 13/22 Servicing or operating apparatus or multistep processes
• CPC Class Codes: F42C 19/0803 characterised by the combination of per se known chemical composition in the priming substance

Abstract

A method includes providing a plurality of particles of an energetic material suspended in a dispersion liquid to an EPD chamber or configuration; applying a voltage difference across a first pair of electrodes to generate a first electric field in the EPD chamber; and depositing at least some of the particles of the energetic material on at least one surface of a substrate, the substrate being one of the electrodes or being coupled to one of the electrodes.

Claims

1. A method, comprising:

providing a plurality of particles of an energetic material suspended in a dispersion liquid to an electrophoretic deposition (EPD) chamber or configuration;

applying a voltage difference across a first pair of electrodes to generate a first electric field in the EPD chamber;

applying a voltage difference across a second pair of electrodes to generate a second electric field in the EPD chamber, wherein the first electric field is different from the second electric field, wherein the first electric field is characterized as a pulse field; and

depositing at least some of the particles of the energetic material on at least one surface of a substrate, the substrate being one of the electrodes or being coupled to one of the electrodes.

2. The method as recited in claim 1, wherein evacuating the dispersion liquid from the EPD chamber is performed at a rate of approximately 2 mL/min.

3. The method as recited in claim 1, further comprising

depositing at least a portion of a plurality of particles of a binding agent above the at least one surface of the substrate,

wherein particles of at least one binding agent are suspended in the dispersion liquid during deposition thereof, and

wherein the particles of the binding agent having a property of enhancing adhesion of the particles of the energetic material to one another and/or the at least one surface of the substrate.

4. The method as recited in claim 1, wherein the energetic material is selected from the group consisting of:

thermites, high explosive materials, and intermetallic materials.

5. The method as recited in claim 1, wherein generating the first electric field comprises generating either a direct-current (DC) field or an alternating-current (AC) field.

6. The method as recited in claim 1, wherein the first electric field is characterized as a pulse field.

7. The method as recited in claim 6, wherein the pulse field is characterized by a shaped pulse.

12. The method as recited in claim 1, wherein the substrate comprises a nanoporous material.

13. The method as recited in claim 1, wherein the substrate comprises a nonconductive structure functional to participate in an energetic reaction of the energetic material.

14. The method as recited in claim 13, wherein the nonconductive structure is porous.

16. The method as recited in claim 1, wherein the substrate is coupled to one of the electrodes.

17. The method as recited in claim 1, wherein at least one secondary agent is added to the suspension of particles of the energetic material in the dispersion liquid.

18. The method as recited in claim 17, wherein the at least one secondary agent and at least some of the particles of the energetic material are codeposited on the at least one surface of the substrate at about a predefined ratio.

19. The method as recited in claim 17, wherein the at least one secondary agent is selected from the group consisting of:

polymers and organic molecules.

20. The method as recited in claim 17, wherein the at least one secondary agent has a property of conferring a surface charge on the at least some of the particles of the energetic material.

8. A method comprising:

providing a plurality of particles of an energetic material suspended in a dispersion liquid to an EPD chamber or configuration;

applying a voltage difference across a first pair of electrodes to generate a first electric field in the EPD chamber;

depositing at least some of the particles of the energetic material on at least one surface of a substrate, the substrate being one of the electrodes or being coupled to one of the electrodes; and

using a second electrode pair for generating a second electric field in the EPD chamber, the second electrode pair comprising;

a third electrode positioned in a third location in the EPD chamber; and

a fourth electrode positioned in a fourth location substantially opposite the third electrode.

9. The method as recited in claim 8, wherein generating the first electric field is performed simultaneous to generating the second electric field.

10. The method as recited in claim 9, the first pair of electrodes comprising a first electrode and a second electrode, wherein a first line intersecting the first electrode and the second electrode is substantially perpendicular to a second line intersecting the third electrode and the fourth electrode, and

wherein generating the first electric field and generating the second electric field comprises generating electric fields having substantially perpendicular axes of orientation.

11. The method as recited in claim 10, wherein generating the first electric field comprises generating a DC field, and

wherein generating the second electric field comprises generating an AC pulse field.

15. A method, comprising:

providing a suspension to an EPD chamber or configuration, the suspension comprising;

a plurality of particles of at least one energetic material selected from the group consisting of;

thermite materials, high explosive materials and intermetallic materials, the particles of the at least one energetic material being suspended in a solution comprising a dispersion liquid and one or more secondary agents having a property of conferring a surface charge on the particles of the energetic material; and

a plurality of particles of at least one binding agent selected from the group consisting of VITON and poly-GLYN, the particles of the at least one binding agent being suspended in the solution;

applying a voltage difference across a first pair of electrodes to generate a DC electric field in the EPD chamber for a duration of about 30 seconds to about 960 seconds, the DC electric field characterized by a field strength of about 1,000 V/m to about 10,000 V/m;

applying a voltage difference across a second pair of electrodes to generate an AC pulse field for a duration in a range from about 30 seconds to about 960 seconds, the AC pulse field characterized by a field strength of about 10 V/cm to about 100V/cm;

depositing a first layer comprising at least a portion of the particles of the energetic material and at least a portion of the particles of the binding agent on at least one surface of a substrate according to a first deposition pattern;

providing a second suspension to the EPD chamber, the second suspension comprising;

a plurality of particles of a second energetic material selected from the group consisting of;

thermite materials, high explosive materials and intermetallic materials, the particles of the at least one energetic material being suspended in a second solution comprising a second dispersion liquid and one or more secondary agents having a property of conferring a surface charge on the particles of the second energetic material; and

a plurality of particles of a second binding agent selected from the group consisting of VITON and poly-GLYN, the particles of the at least one binding agent being suspended in the second solution;

applying a voltage difference across the first pair of electrodes to generate the DC electric field in the EPD chamber for a duration in a range from about 30 seconds to about 960 seconds, the DC electric field characterized by a field strength of about 1,000 V/m to about 10,000 V/m;

applying a voltage difference across the second pair of electrodes to generate the AC pulse field for a duration in the range from about 30 seconds to about 960 seconds, the AC pulse field characterized by a field strength of about 10 V/cm to about 100V/cm; and

depositing a second layer comprising at least a portion of the particles of the second energetic material and at least a portion of the particles of the second binding agent on at least one surface of the substrate according to a second deposition pattern,

wherein a first line intersecting the first pair of electrodes is substantially perpendicular to a second line intersecting the second pair of electrodes,

wherein generating the DC electric field is performed simultaneous to generating the AC pulse field, and

wherein generating the DC electric field and generating the AC pulse field simultaneously comprises generating electric fields having substantially perpendicular axes of orientation.