Alloys for inert matrix fuel compositions, and methods of making the same

1. An alloy, comprising:

Zr;

Fe;

Cu;

Ta in an amount from about 1 wt % to about 3 wt %; and

one or more optional constituents selected from: Ti, Be, and Nb; and

wherein the alloy comprises a ductile phase and a nanoprecipitate hard phase.

2. The alloy as recited in claim 1 , wherein at least 95 vol % of the alloy is characterized by a body-centered-cubic (BCC) crystalline phase.

3. The alloy as recited in claim 1 , wherein the nanoprecipitate hard phase occupies approximately 0.01 vol % to approximately 0.1 vol % of the alloy; and wherein the nanoprecipitate hard phase comprises; the Fe and/or the Ti.

4. A composition of matter comprising the alloy as recited in claim 1 , wherein the alloy is formed into a matrix having particles of a fuel dispersed throughout the matrix.

5. The composition of matter as recited in claim 4 , comprising a plurality of pores dispersed throughout the matrix.

6. The composition of matter as recited in claim 4 , comprising a metal cladding surrounding the matrix.

7. The composition of matter as recited in claim 6 , comprising a metallic coating layer between the matrix and the metal cladding.

8. The alloy as recited in claim 1 , wherein the alloy is characterized by a formula Zr x Fe y Cu z Ta a , wherein:

x is a value in a range from about 55 to about 95 wt %;

y is a value in a range from about 2.5 to about 15 wt %;

z is a value in a range from about 0.5 to about 5 wt %; and

a is a value in a range from about 1 to about 3 wt %.

9. The alloy as recited in claim 1 , wherein the alloy is characterized by a formula Zr x Fe y Cu z Ta a Ti b ; and wherein:

x is a value in a range from 58.5 to 73 wt %;

y is a value in a range from 10 to 20 wt %;

z is a value in a range from 1.5 to 5 wt %;

a is a value in a range from about 1 to about 3 wt %; and

b is a value in a range from about 12 to about 20 wt %.

10. The alloy as recited in claim 1 , wherein the alloy is characterized by a formula Zr x Fe y Cu z Ta a M 1 b ; and wherein:

x is a value in a range from about 55 to about 95 wt %;

y is a value in a range from about 2.5 to about 15 wt %;

z is a value in a range from about 0.5 to about 5 wt %;

a is a value in a range from about 1 to about 3 wt %;

M 1 includes as least one additional constituent selected from: Ti, Nb and Be; and

b is a value in a range from about 1 to about 20 wt %.

11. The alloy as recited in claim 1 , wherein the alloy is characterized by a formula Zr x Fe y Cu z M 1 a Ta b , wherein:

x is a value in a range from about 55 to about 90 wt %;

y is a value in a range from about 5 to about 15 wt %;

z is a value in a range from about 0.5 to about 5 wt %;

M 1 is selected from Ti, Nb and Be;

a is a value in a range from about 1 to about 20 wt %; and

b is a value in a range from about 1 to about 3 wt %.

12. The alloy as recited in claim 11 , wherein:

x is a value in a range from 66 to 85 wt %;

y is a value in a range from 4 to 7 wt %;

z is a value in a range from 1 to 3 wt %;

M 1 is Ti or Nb; and

a is a value in a range from 5 to 20 wt %.

13. A method of forming an inert matrix nuclear fuel, comprising:

packing a hollow structure with fuel pellets and alloy precursor pellets;

heating the fuel pellets and the alloy precursor pellets to at least a melting temperature of an alloy to be formed by melting the alloy precursor pellets; and

solidifying the alloy into a matrix surrounding the fuel pellets;

wherein the alloy comprises:

Zr;

Fe;

Cu;

Ta present in an amount from about 1 to about 3 wt %; and

one or more optional alloy constituents selected from: Ti, Be, and Nb; and

wherein the alloy comprises a ductile phase and a nanoprecipitate hard phase.

14. The method as recited in claim 13 , wherein the melting temperature of the alloy is in a range from approximately 600° C. to approximately 950° C.

15. The method as recited in claim 13 , wherein heating the alloy precursor pellets causes the alloy to coat the fuel pellets via capillary action.

16. The method as recited in claim 13 , comprising forming a metallic coating layer of the alloy on interior surfaces of the hollow structure prior to packing the hollow structure.

17. The method as recited in claim 13 , wherein approximately 95 vol % or more of the alloy is characterized by a body-centered-cubic (BCC) crystalline phase.

18. The method as recited in claim 13 , wherein the solidified alloy forms a continuous matrix, the continuous matrix further comprising a plurality of pores.

19. The method as recited in claim 13 , wherein the alloy is characterized by a formula Zr x Fe y Cu z Ta a , where:

x is a value in a range from about 55 to about 95 wt %;

y is a value in a range from about 2.5 to about 15 wt %;

z is a value in a range from about 0.5 to about 5 wt %; and

a is a value in a range from about 1 to about 3 wt %.

20. The method as recited in claim 13 , wherein the alloy is characterized by a formula Zr x Fe y Cu z M 1 a Ta b , where:

x is a value in a range from about 55 to about 90 wt %;

y is a value in a range from about 5 to about 15 wt %;

z is a value in a range from about 0.5 to about 5 wt %;

M 1 is selected from Nb, Ti and Be;

a is a value in a range from about 1 to about 20 wt %; and

b is a value in a range from about 1 to about 3 wt %.