WE CLAIM:
1. A silicon-based patch formulation comprising:
about 25 to 66 percent by volume of a solvent;
about 4 to10 percent by volume of a silicon-comprising binding material; and
about 30 to 65 percent by volume of a patching material, the patching material
comprising particles having one or more non-actinide Group IIIA elements, wherein a
molar ratio of the one or more non-actinide Group IIIA elements to silicon within the
silicon-based patch formulation is about 0.95 to 1.25.
2. The silicon-based patch formulation as claimed in claim 1, wherein the particles having one or more non-actinide Group IIIA elements comprise one or more rare earth materials selected from a group consisting of a rare earth monosilicate (RE2SiO5) and a rare earth disilicate (RE2Si2O7), wherein the rare earth material is chosen from a group consisting of non-actinide Group IIIA elements.
3. The silicon-based patch formulation as claimed in claim 1, wherein the particles having one or more non-actinide Group IIIA elements have at least a bimodal particle size distribution, wherein a particle size of a peak of a first distribution is greater than a particle size of a peak of a second distribution.
4. The silicon-based patch formulation as claimed in claim 3, wherein a volume fraction of the first distribution comprises fewer than 80 percent of the patching material and a volume fraction of the second distribution comprises fewer than 80 percent of the patching material, wherein a volume fraction of the first and the second distributions comprises substantially 100% of the patching material.
5. The silicon-based patch formulation as claimed in claim 3, wherein a volume fraction of the first distribution comprises fewer than 60 percent of the patching material and a volume fraction of the second distribution comprises fewer than 60
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percent of the patching material, wherein a volume fraction of the first and the second distributions comprises substantially 100% of the patching material.
6. The silicon-based patch formulation as claimed in claim 3, wherein the particle size of the first distribution is within a range of about 10 to 50 µm, and the particle size of the second distribution is within a range of about 0.5 to 10 µm.
7. The silicon-based patch formulation as claimed in claim 1, wherein the particles having one or more non-actinide Group IIIA elements have at least a trimodal particle size distribution, wherein a particle size of a peak of a first distribution is greater than a particle size of a peak of a second distribution, the particle size of the peak of the second distribution is greater than a particle size of a peak of a third distribution.
8. The silicon-based patch formulation as claimed in claim 7, wherein a volume fraction of the first distribution comprises fewer than 80 percent of the patching material, a volume fraction of the second distribution comprises fewer than 50 percent of the patching material, and a volume fraction of the third distribution comprises fewer than 50 percent of the patching material, wherein a volume fraction of the first, the second and the third distributions comprises substantially 100% of the patching material
9. The silicon-based patch formulation as claimed in claim 7, wherein a volume fraction of the first distribution comprises fewer than 60 percent of the patching material, a volume fraction of the second distribution comprises fewer than 30 percent of the patching material, and a volume fraction of the third distribution comprises fewer than 30 percent of the patching material, wherein a volume fraction of the first, the second and the third distributions comprises substantially 100% of the patching material.
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10. The silicon-based patch formulation as claimed in claim 6, wherein the particle size of the first distribution is within a range of about 10 to 50 µm, the particle size of the second distribution is within a range of about 5 to 15 µm, and the particle size of the third distribution is within a range of about 0.5 to 5µm.
11. The silicon-based patch formulation as claimed in claim 1, wherein the solvent comprises an organic solvent which facilitates dissolution of the silicon-comprising binding material.
12. The silicon-based patch formulation as claimed in claim 11, wherein the organic solvent is chosen from a group consisting of methanol, ethanol, butanol, propanol, pentanol, hexanol, octanol, nonanol, decanol, dodecanol.
13. The silicon-based patch formulation as claimed in claim 1, wherein the binding material comprises a cross-linked polyorganosiloxane resin.
14. A silicon-based environmentally resistant patch comprising:
about 2 to 10 percent by volume of a cured silicon-comprising binding material;
about 90 to 98 percent by volume of a cured patching material, wherein the cured patching material comprises particles having one or more non-actinide Group IIIA elements; and
wherein a molar ratio of the one or more non-actinide Group IIIA elements to silicon within the silicon-based environmentally resistant patch is about 0.95 to 1.25.
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15. The silicon-based environmentally resistant patch of claim 14, further comprising an adhesive strength of at least about 3 MPa and a coefficient of thermal expansion of about 3.5 to 7ppm /oC.
16. The silicon-based environmentally resistant patch as claimed in claim 14, wherein the particles having one or more non-actinide Group IIIA elements comprise one or more rare earth materials selected from a group consisting of a rare earth monosilicate (RE2SiO5) and a rare earth disilicate (RE2Si2O7), and wherein the rare earth material is chosen from a group consisting of non-actinide Group IIIA elements.
17. The silicon-based environmentally resistant patch as claimed in claim 14, wherein the particles having one or more non-actinide Group IIIA elements have at least a bimodal particle size distribution, wherein a particle size of a peak of a first distribution is greater than a particle size of a peak of second distribution.
18. The silicon-based environmentally resistant patch as claimed in claim 17, wherein a volume fraction of the first distribution comprises fewer than 60 percent of the cured patching material and the volume fraction of the second distribution comprises fewer than 60 percent of the cured patching material, wherein a volume fraction of the first and the second distributions comprises substantially 100% of the patching material.
19. The silicon-based environmentally resistant patch as claimed in claim 17, wherein the particle size of the first distribution is within a range of about 10 to 50 µm, and the particle size of the second distribution is within a range of about 0.5 to 10 µm.
20. The silicon-based environmentally resistant patch as claimed in claim 14, wherein the particles having one or more non-actinide Group IIIA elements have at
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least a trimodal particle size distribution, wherein a particle size of a peak of a first distribution is greater than a particle size of a peak of a second distribution, the particle size of the peak of the second distribution is greater than a particle size of a peak of a third distribution.
21. The silicon-based environmentally resistant patch as claimed in claim 20, wherein a volume fraction of the first distribution comprises fewer than 60 percent of the cured patching material, a volume fraction of the second distribution comprises fewer than 30 percent of the cured patching material, and a volume fraction of the third distribution comprises fewer than 30 percent of the cured patching material, wherein a volume fraction of the first, the second and the third distributions comprises substantially 100% of the patching material.
22. The silicon-based environmentally resistant patch as claimed in claim 20, wherein the particle size of the first distribution is within a range of about 10 to 50 µm, the particle size of the second distribution is within a range of about 5 to 15 µm, and the particle size of the third distribution is within a range of about 0.5 to 5 µm.
23. The silicon-based environmentally resistant patch as claimed in claim 14, wherein the cured silicon-comprising binding material comprises a cured cross-linked polyorganosiloxane resin, the cured cross-linked polyorganosiloxane resin comprising silica.
24. A method comprising:
heat treating a silicon-based patch formulation disposed within a cavity of a silicon-based substrate, the heat treating facilitating forming a silicon-based environmentally-resistant patch within the cavity, wherein the silicon-based environmentally-resistant patch comprises a cured silicon-
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comprising binding material and a cured patching material comprising particles having one or more non-actinide Group IIIA elements, and wherein a molar ratio of the one or more non-actinide Group IIIA elements to silicon within the silicon-based environmentally-resistant patch is about 0.95 to 1.25.
25. The method as claimed in claim 24, wherein the heat treating comprises subjecting the silicon-based patch formulation to a curing, wherein the curing of the silicon-based patch formulation is performed at a maximum temperature between about 1000oC and 1650oC .
26. The method as claimed in claim 24, wherein the heat treating comprises stabilizing the silicon-based patch formulation, prior to curing, the stabilizing of the silicon-based patch formulation being performed at a temperature of about 500oC or less
27. The method as claimed in claim 24, wherein the silicon-based patch formulation comprises providing a silicon-based patch formulation comprising about 25 to 66 percent by volume of a solvent, about 4 to 10 percent by volume of a silicon-comprising binding material; and about 30 to 65 percent by volume of a patching material, the patching material comprising particles having one or more non-actinide Group IIIA elements, wherein a molar ratio of the one or more non-actinide Group IIIA element to silicon within the silicon-based patch formulation is from about 0.95 to 1.25.
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28. The method as claimed in claim 27, wherein the particles having one or more non-actinide Group IIIA elements comprise one or more rare earth material selected from a group consisting of a rare earth monosilicate (RE2SiOs) and a rare earth disilicate (RE2Si207), wherein the rare earth material is chosen from a group consisting of the non-actinide Group IIIA elements.
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