Fine grain niobium sheet via ingot metallurgy
View Patent ↗In various embodiments, metallic products are formed by alloying niobium with at least one of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum, or cerium and processing the alloy.
1. A method for forming a metallic product, the method comprising:
melting niobium to form a melt;
adding an amount greater than 5 ppm and no greater than 100 ppm, based on the niobium in the melt, of a metal consisting of at least one of yttrium, aluminum, hafnium, titanium, zirconium, thorium, lanthanum, or cerium to form a melted blend consisting of only the niobium and the metal in an amount greater than 5 ppm and no greater than 100 ppm;
cooling the melted blend to form an alloy ingot; and
thermo-mechanically processing the alloy ingot to form a wrought product having a uniform ASTM grain size of 5 to 10.
2. The method of claim 1 , wherein thermo-mechanically processing the alloy ingot comprises (i) forging the alloy ingot to form the wrought product and (ii) annealing the wrought product.
3. The method of claim 2 , wherein the wrought product is annealed at a temperature selected from the range of 950° C. to 1150° C.
4. The method of claim 2 , wherein the wrought product is at least 75% recrystallized after annealing.
5. The method of claim 1 , wherein the wrought product is a foil, a sheet, a plate, a tube, or a rod.
6. The method of claim 1 , wherein thermo-mechanically processing the alloy ingot comprises (i) rolling the alloy ingot and (ii) annealing the rolled alloy ingot.
7. The method of claim 6 , wherein the rolled alloy ingot is annealed at a temperature selected from the range of 950° C. to 1150° C.
8. The method of claim 1 , wherein the metal consists of at least one of aluminum, hafnium, titanium, or zirconium.
9. The method of claim 8 , wherein the metal consists of aluminum.
10. The method of claim 8 , wherein the metal consists of hafnium.
11. The method of claim 8 , wherein the metal consists of titanium.
12. The method of claim 8 , wherein the metal consists of zirconium.
13. The method of claim 1 , wherein adding the metal to the niobium to form the melted blend comprises melting the metal with the niobium.
14. The method of claim 1 , wherein the melted blend consists of only the niobium and the metal in an amount greater than 5 ppm and no greater than 60 ppm.
15. The method of claim 1 , wherein the melted blend consists of only the niobium and the metal in an amount greater than 5 ppm and no greater than 50 ppm.