Refractory metal pots
View Patent ↗In accordance with various embodiments, plates are formed via a plurality of upset-forging and forging-back cycles followed by a plurality of rolling passes.
1. A method of manufacturing a refractory-metal target from a refractory-metal workpiece having a longitudinal axis and a first dimension substantially perpendicular to the longitudinal axis, the method comprising:
without flat-forging the workpiece along an axis substantially perpendicular to the longitudinal axis:
(i) upset forging the workpiece along the longitudinal axis, thereby increasing the first dimension of the workpiece and forming a second workpiece,
(ii) annealing the second workpiece to at least partially recrystallize the second workpiece,
(iii) forging back the annealed second workpiece along the longitudinal axis, thereby decreasing the first dimension of the annealed second workpiece and forming a third workpiece,
(iv) upset forging the third workpiece along the longitudinal axis, thereby increasing the first dimension of the third workpiece and forming a fourth workpiece,
(v) forging back the fourth workpiece along the longitudinal axis, thereby decreasing the first dimension of the fourth workpiece and forming a fifth workpiece,
(vi) annealing the fifth workpiece to at least partially recrystallize the fifth workpiece,
(vii) upset forging the annealed fifth workpiece along the longitudinal axis, thereby increasing the first dimension of the annealed fifth workpiece and forming a sixth workpiece, and
(viii) annealing the sixth workpiece; and
thereafter, and without flat-forging the annealed sixth workpiece along an axis substantially perpendicular to the longitudinal axis therebetween, forming the annealed sixth workpiece into a plate via a plurality of rolling cycles performed substantially perpendicular to the longitudinal axis, the annealed sixth workpiece being turned between at least two of the rolling cycles, and a thickness of the plate along the longitudinal axis decreasing during at least one rolling cycle.
2. The method of claim 1 , further comprising cutting the workpiece from an ingot prior to deforming the workpiece, the ingot comprising a refractory metal.
3. The method of claim 1 , further comprising deep drawing the plate into a pot.
4. The method of claim 3 , further comprising attaching a collar to the pot.
5. The method of claim 4 , wherein attaching the collar to the pot comprises welding.
6. The method of claim 3 , further comprising annealing the pot.
7. The method of claim 1 , wherein at least one of the second, fifth, or sixth workpieces is annealed in vacuum or an inert gas.
8. The method of claim 1 , wherein annealing the sixth workpiece at least partially recrystallizes the sixth workpiece.
9. The method of claim 1 , wherein the thickness of the plate along the longitudinal axis decreases during each rolling cycle.
10. The method of claim 1 , further comprising attaching the plate to a backing plate.
11. The method of claim 1 , wherein, after formation of the plate, a grain size of the plate is substantially uniform.
12. The method of claim 1 , further comprising determining at least one of an interim dimension of at least one of the workpieces or a final dimension of the plate via computer-implemented finite-element modeling.
13. The method of claim 1 , further comprising forming the plate into a pot by pressing the plate against a die, a dimension of the die being determined via computer-implemented finite-element modeling.
14. The method of claim 1 , wherein the workpiece comprises at least one of niobium, tantalum, molybdenum, tungsten, or an alloy or mixture thereof
15. The method of claim 1 , wherein the workpiece is substantially cylindrical and the first dimension is a diameter.
16. The method of claim 1 , wherein turning the annealed sixth workpiece comprises rotating the annealed sixth workpiece about the longitudinal axis.