Composite reactive material for use in a munition

Abstract

A composite reactive material for use in a munition is disclosed. The composite reactive material comprises a metal lattice structure having interstitial spaces and a powder in the interstitial spaces. The powder comprises at least one metal powder and/or at least one halogen-containing polymer powder.

Claims

1. A method of producing a composite reactive material for use in a munition, the method comprising: a. selective laser melting of a metal powder to fabricate a metal lattice structure having interstitial spaces; b. infiltrating a powder comprising at least one metal powder or at least one halogen-containing polymer powder into the interstitial spaces; and c. consolidating the powder in the interstitial spaces.

2. A method according to claim 1 wherein cold isostatic pressing or hot isostatic pressing is used to aid infiltration of the powder into the interstitial spaces.

3. A method according to claim 1 wherein cold isostatic pressing or hot isostatic pressing is used to consolidate the powder in the interstitial spaces.

4. A method according to claim 1 wherein the porosity of the metal lattice structure is in the range 15%-85% by volume.

5. A method according to claim 1 wherein the mesh size of the metal lattice structure is in the range 0.5-5 mm.

6. A method according to claim 1 wherein the metal powder comprises at least one of titanium, aluminium, zirconium, hafnium, tantalum, molybdenum, tungsten, iron or alloys thereof.

7. A method according to claim 1 wherein the halogen-containing polymer is a fluoropolymer.

8. A method according to claim 7 wherein the fluoropolymer comprises at least one of PFA, PTFE, THV, Viton, Fluore or Kel.

9. A method according to claim 1 wherein the powder comprises at least one metal powder and at least one halogen-containing polymer powder.

10. A method according to claim 9 wherein the powder comprises two metal powders and two halogen-containing polymer powders.

11. A method according to claim 1 wherein the porosity of the composite reactive material is 0-20%.

12. A method according to claim 1 wherein the metal lattice structure comprises a multilayered mesh framework.

13. A method according to claim 1 wherein the metal lattice structure comprises a uniform mesh.

14. A method according to claim 1 wherein the metal lattice structure comprises legs having a thickness of less than 500 micron.

15. A method according to claim 1 wherein the metal lattice structure comprises legs having a thickness of less than 300 micron.

16. A method according to claim 1 wherein the metal lattice structure comprises a plurality of interlinked interstitial spaces.

17. A method according to claim 16 wherein the interlinked interstitial spaces are greater than 2 times the powder size.

18. A method according to claim 16 wherein the interlinked interstitial spaces are greater than 10 times the powder size.

19. A method according to claim 1 wherein the metal lattice structure is produced to be netshape using selective laser melting.

20. A method according to claim 1 wherein the metal lattice structure is produced to be near netshape using selective laser melting.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Example embodiments of the invention will now be described by way of example only and with reference to the accompanying drawings, of which:

(2) FIG. 1 is a view of a metal lattice structure of a first embodiment of the invention;

(3) FIG. 2 is a view of a composite reactive material according to a second embodiment of the invention;

(4) FIG. 3 is a view a composite reactive material according to a third embodiment of the invention;

(5) FIG. 4 is a view of a metal lattice structure of a fourth embodiment of the invention; and

(6) FIG. 5 is a schematic flowchart of a manufacturing process according to a fifth embodiment of the invention.

DETAILED DESCRIPTION

(7) In FIG. 1 a metal lattice structure 3 has been produced by selective laser melting (SLM). The metal lattice structure 3 is a multi-layered mesh structure made from a Titanium alloy. The metal lattice structure 3 comprises interstitial spaces 9 into which a powder can be infiltrated.

(8) In FIG. 2 a composite reactive material 11 is formed from a metal lattice structure 13 and a powder 15 infiltrated into the interstitial spaces 19 and consolidated. The powder 15 comprises titanium powder and PTFE powder and has been cold isostatic pressed. The metal lattice structure 13 is made from a titanium alloy.

(9) In FIG. 3 a composite reactive material 21 is formed from a metal lattice structure 23 and a powder 25 infiltrated into the interstitial spaces 29 and consolidated. The powder 25 comprises titanium powder and PTFE powder and has been hot isostatic pressed at 150 MPa and 340 C. The metal lattice structure 23 is made from titanium.

(10) In FIG. 4 a metal lattice structure 33 in the form of a warhead casing 37 has been produced by SLM. The metal lattice structure 33 is a multi-layered mesh structure made from a titanium alloy. The metal lattice structure 33 comprises interstitial spaces 39 into which a powder can be infiltrated. The metal lattice structure 33 has a porosity of 75% by volume with a mesh size of 4 mm. The warhead casing 37 has a dense metal top 36 to provide dimensional stability.

(11) In FIG. 5 a lattice 41 is formed from a metal powder 42 by SLM 43. A metal powder 44 and a fluoropolymer powder 45 are mixed, blended and milled 46 and infiltrated into the lattice 41 using hot or cold isostatic pressing 47. The resulting composite is finished by machining 48 to produce a warhead component 49.

(12) Whilst the present invention has been described and illustrated with reference to particular embodiments, it will be appreciated by those of ordinary skill in the art that the invention lends itself to many different variations not specifically illustrated herein. For example, the metal lattice structure may have a porosity of 50% by volume with a mesh size of 3 mm or a porosity of 25% by volume with a mesh size of 2 mm.

(13) Where in the foregoing description, integers or elements are mentioned which have known, obvious or foreseeable equivalents, then such equivalents are herein incorporated as if individually set forth. Reference should be made to the claims for determining the true scope of the present invention, which should be construed so as to encompass any such equivalents. It will also be appreciated by the reader that integers or features of the invention that are described as preferable, advantageous, convenient or the like are optional and do not limit the scope of the independent claims. Moreover, it is to be understood that such optional integers or features, whilst of possible benefit in some embodiments of the invention, may be absent in other embodiments.