Patent Number: 058870440
Section: claims

1. A uranium-free fuel for a fast nuclear reactor comprising an alloy of Pu, Zr and Hf, wherein Hf is present in an amount less than about 10% by weight of the alloy. 2. The fuel of claim 1, wherein the Pu is present as an alloy of Pu--28(Zr, Hf). 3. The fuel of claim 2, wherein the Hf is present in the range of from about 1% to about 5%. 4. The fuel of claim 1, wherein the Hf is present in the range of from about 1% to about 5%. 5. The fuel of claim 1, wherein the solidus temperature of the Pu alloy is not less than about 1000.degree. C. 6. The fuel of claim 2, and further comprising a cladding material surrounding said fuel defining an annular area between said cladding and said Pu--28 (Zr, Hf) alloy, and an alkali metal in said annular area. 7. The fuel of claim 6, wherein said alkali metal is Na. 8. The fuel of claim 7, wherein said cladding is a stainless steel. 9. The fuel of claim 1, and further comprising a cladding material surrounding said fuel defining an annular area between said cladding and said alloy of Pu, Zr and Hf, and an alkali metal in said annular area. 10. The fuel of claim 9, wherein said alkali metal is Na and said cladding is a stainless steel. 11. A uranium-free fuel for a fast nuclear reactor comprising an alloy of Pu, an alloy of Hf and Zr surrounding said Pu alloy, a cladding spaced from and surrounding said Hf and Zr alloy defining an annulus therebetween, and a bonding material between said cladding and Hf--Zr alloy wherein Hf is present in an amount not more than 10% by wt of the combined weight of the Pu--Zr--Hf alloy. 12. The uranium-free fuel of claim 11, wherein Hf is present in an amount in the range of from about 1% to about 5% by weight of the combined weight of the Pu--Zr--Hf alloy. 13. The uranium-free fuel of claim 12, wherein the Pu alloy is a Pu--Zr alloy and this Pu--Zr alloy is Pu--28(Zr, Hf) where the Hf content of the Pu--28(Zr, Hf) and the alloy of Hf and Zr does not exceed about 10% by weight of the combined weight of the Pu--Zr--Hf alloy and the Zr--Hf alloy .