Illumination compositions, illumination flares including the illumination compositions, and related methods

1. An illumination composition, comprising:

at least one oxidizer selected from the group consisting of a potassium-containing oxidizer and a rubidium-containing oxidizer, the at least one oxidizer present in the illumination composition at from about 50 percent by weight to about 70 percent by weight and comprising:

larger particles each independently having a particle size within a range of from about 275 μm to about 325 μm, the larger particles present in the illumination composition at from about 35 wt % to about 55 wt %; and

smaller particles each independently having a particle size within a range of from about 25 μm to about 35 μm, the smaller particles present in the illumination composition at from about 15 wt % to about 30 wt %;

at least one of a fuel and a binder; and

at least one combustion rate modifier.

2. The illumination composition of claim 1 , wherein the larger particles and the smaller particles comprise different oxidizers than one another.

3. The illumination composition of claim 1 , wherein the at least one oxidizer is KNO 3 .

4. The illumination composition of claim 1 , further comprising at least one cesium-containing oxidizer.

5. The illumination composition of claim 4 , wherein the cesium-containing oxidizer is present in the illumination composition at less than or equal to about 5 wt %.

6. The illumination composition of claim 5 , wherein the cesium-containing oxidizer comprises CsNO 3 particles each independently having a size within a range of from about 40 μm to about 65 μm.

7. The illumination composition of claim 1 , wherein the at least one of a fuel and a binder comprises elemental silicon particles present in the illumination composition at from about 4 wt % to about 20 wt %, the elemental silicon particles each independently having a size within a range of from about 5 μm to about 15 μm.

8. The illumination composition of claim 1 , wherein the at least one of a fuel and a binder comprises the fuel and the binder, the fuel present in the illumination composition at from about 4 wt % to about 20 wt %, and the binder present in the illumination composition at from about 1 wt % to about 50 wt %.

9. The illumination composition of claim 1 , wherein the at least one combustion rate modifier is selected from the group consisting of amorphous boron and a high surface area metal oxide.

10. The illumination composition of claim 1 , wherein the at least one combustion rate modifier comprises at least one of a high surface area iron oxide and a high surface area aluminum oxide.

11. The illumination composition of claim 1 , wherein the at least one combustion rate modifier comprises amorphous boron and a high surface area iron oxide, the amorphous boron present in the illumination composition at from about 2 wt % to about 5 wt %, and the high surface area iron oxide present in the illumination composition at from about 0.5 wt % to about 1 wt %.

12. An illumination composition, comprising:

at least one oxidizer selected from the group consisting of a potassium-containing oxidizer, a rubidium-containing oxidizer, and a cesium-containing oxidizer and comprising:

larger particles each independently having a particle size within a range of from about 275 μm to about 325 μm, the larger particles present in the illumination composition at from about 35 wt % to about 55 wt %; and

smaller particles each independently having a particle size within a range of from about 25 μm to about 35 μm, the smaller particles present in the illumination composition at from about 15 wt % to about 30 wt %;

at least one of a fuel and a binder; and

at least one metal oxide exhibiting a specific surface area of greater than or equal to about 90 m 2 /g.

13. The illumination composition of claim 12 , wherein the at least one oxidizer comprises at least one of CsNO 3 , CsClO 3 , CsClO 4 , Cs 2 O 2 , KNO 3 , KClO 3 , KClO 4 , K 2 O 2 , RbNO 3 , RbClO 3 , RbClO 4 , and Rb 2 O 2 .

14. The illumination composition of claim 12 , wherein the at least one oxidizer comprises KNO 3 and CsNO 3 , the KNO 3 present in the illumination composition at from about 50 wt % to about 70 wt %, and the CsNO 3 present in the illumination composition at less than or equal to about 5 wt %.

15. The illumination composition of claim 12 , wherein the at least one metal oxide comprises at least one of an iron oxide and an aluminum oxide.

16. The illumination composition of claim 12 , wherein the at least one metal oxide comprises an iron oxide exhibiting a specific surface area of greater than or equal to about 93 m 2 /g.

17. The illumination composition of claim 12 , wherein the at least one metal oxide comprises an iron oxide present in the illumination composition at less than or equal to about 0.25 wt %.

18. The illumination composition of claim 12 , further comprising a boron material comprising from about 85 wt % amorphous boron to about 100 wt % amorphous boron, the amorphous boron present in the illumination composition at from about 0.5 wt % to about 10 wt %.

19. An illumination flare, comprising:

a casing; and

an illumination composition contained within the casing and comprising:

at least one oxidizer selected from the group consisting of a potassium-containing oxidizer and a rubidium-containing oxidizer, the at least one oxidizer present in the illumination composition at from about 50 percent by weight to about 70 percent by weight and comprising:

larger particles each independently having a particle size within a range of from about 275 μm to about 325 μm, the larger particles present in the illumination composition at from about 35 wt % to about 55 wt %; and

smaller particles each independently having a particle size within a range of from about 25 μm to about 35 μm, the smaller particles present in the illumination composition at from about 15 wt % to about 30 wt %;

at least one of a fuel and a binder; and

at least one combustion rate modifier.

20. The illumination flare of claim 19 , wherein the at least one oxidizer comprises the potassium-containing oxidizer, the potassium-containing oxidizer present in the illumination composition at from about 45 wt % to about 65 wt %.

21. The illumination flare of claim 20 , further comprising at least one cesium-containing oxidizer, the cesium-containing oxidizer present in the illumination composition at from about 1 wt % to about 5 wt %.

22. The illumination flare of claim 19 , wherein the at least one combustion rate modifier comprises a high surface area metal oxide, the high surface area metal oxide present in the illumination composition at from about 0.25 wt % to about 2.0 wt %.

23. The illumination flare of claim 19 , wherein the at least one of a fuel and a binder comprises elemental silicon, a ratio of the elemental silicon to the at least one oxidizer within a range of from about 1.4 to about 2.0.

24. A method of illumining a target, comprising:

deploying an illumination flare comprising a casing and an illumination composition contained within the casing, the illumination composition comprising:

at least one oxidizer selected from the group consisting of a potassium-containing oxidizer and a rubidium-containing oxidizer, the at least one oxidizer present in the illumination composition at from about 50 percent by weight to about 70 percent by weight and comprising:

larger particles each independently having a particle size within a range of from about 275 μm to about 325 μm, the larger particles present in the illumination composition at from about 35 wt % to about 55 wt %; and

smaller particles each independently having a particle size within a range of from about 25 μm to about 35 μm, the smaller particles present in the illumination composition at from about 15 wt % to about 30 wt %;

at least one of a fuel and a binder; and

at least one combustion rate modifier; and

combusting the illumination composition to produce near infrared radiation.