Methods of modifying material properties of workpieces using high-pressure-torsion apparatuses

Patent metadata

Field	Value
Publication number	US-10907226-B2
Application number	US-201816227516-A
Country	US
Kind code	B2
Filing date	Dec 20, 2018
Priority date	Dec 20, 2018
Publication date	Feb 2, 2021
Grant date	Feb 2, 2021

Abstract

Described is a method of modifying material properties of a workpiece using a high-pressure-torsion apparatus, comprising a working axis, a first anvil, a second anvil, and an annular body, comprising a first total-loss convective chiller, a second total-loss convective chiller, and a heater, positioned between the first total-loss convective chiller and the second total-loss convective chiller along the working axis. The method comprises compressing the workpiece along a central axis of the workpiece and, simultaneously with compressing the workpiece along the central axis, twisting the workpiece about the central axis. The method further comprises, while compressing the workpiece along the central axis and twisting the workpiece about the central axis, translating the annular body along the working axis of the high-pressure-torsion apparatus, collinear with the central axis of the workpiece, and heating the workpiece with the heater.

First claim

What is claimed is:

1. A method of modifying material properties of a workpiece using a high-pressure-torsion apparatus, comprising a working axis, a first anvil, a second anvil, and an annular body, comprising a first total-loss convective chiller, a second total-loss convective chiller, and a heater, positioned between the first total-loss convective chiller and the second total-loss convective chiller along the working axis, the method comprising steps of:
compressing the workpiece along a central axis of the workpiece;
simultaneously with compressing the workpiece along the central axis, twisting the workpiece about the central axis;
while compressing the workpiece along the central axis and twisting the workpiece about the central axis, translating the annular body along the working axis of the high-pressure-torsion apparatus, collinear with the central axis of the workpiece, and heating the workpiece with the heater; and
at least one of cooling the workpiece with the first total-loss convective chiller or a step of cooling the workpiece with the second total-loss convective chiller, simultaneously with the step of heating the workpiece,
wherein:
the step of cooling the workpiece-with the first total-loss convective chiller-comprises steps of routing a first cooling fluid through the first total-loss convective chiller and contacting a portion of the workpiece with the first cooling fluid, exiting the first total-loss convective chiller; and
the step of cooling the workpiece with the second total-loss convective chiller comprises steps of routing a second cooling fluid through the second total-loss convective chiller and contacting a portion of the workpiece with the second cooling fluid, exiting the second total-loss convective chiller.

2. The method according to claim 1 , wherein the step of heating the workpiece with the heater is independent from the step of cooling the workpiece with the first total-loss convective chiller or the step of cooling the workpiece with the second total-loss convective chiller.

3. The method according to claim 2 , wherein the step of heating the workpiece with the heater is performed while the workpiece is not cooled by at least one of the first total-loss convective chiller or the second total-loss convective chiller.

4. The method according to claim 1 , wherein the step of routing the first cooling fluid through the first total-loss convective chiller and the step of routing the second cooling fluid through the second total-loss convective chiller are independently controlled.

5. The method according to claim 4 , wherein:
the annular body comprises a central opening, configured to surround the workpiece;
the step of routing the first cooling fluid through the first total-loss convective chiller comprises a step of discharging the first cooling fluid into the central opening; and
the step of routing the second cooling fluid through the second total-loss convective chiller comprises a step of discharging the second cooling fluid into the central opening.

6. The method according to claim 5 , wherein:
the first total-loss convective chiller comprises a first-chiller channel, having a first-chiller-channel inlet and a first-chiller-channel outlet, spaced away from the first-chiller-channel inlet;
the first-chiller-channel outlet is directed at the workpiece;
the second total-loss convective chiller comprises a second-chiller channel, having a second-chiller-channel inlet and a second-chiller-channel outlet, spaced away from the second-chiller-channel inlet; and
the second-chiller-channel outlet is directed at the workpiece.

7. The method according to claim 6 , wherein:
the high-pressure-torsion apparatus further comprises:
a first thermal seal, located between the heater and the first-chiller-channel outlet along the working axis and in contact with the workpiece, such that the first thermal seal prevents the first cooling fluid from flowing into a space between the heater and the workpiece; and
a second thermal seal, located between the heater and the second-chiller-channel outlet along the working axis and in contact with the workpiece, such that the second thermal seal prevents the second cooling fluid from flowing into a space between the heater and the workpiece.

8. The method according to claim 7 , further comprising a step of thermally conductively isolating the heater and the first total-loss convective chiller from each other using a first thermal barrier while the step of heating the workpiece with the heater is performed simultaneously with at least one of the step of cooling the workpiece with the first total-loss convective chiller or the step of cooling the workpiece with the second total-loss convective chiller.

9. The method according to claim 7 , further comprising a step of thermally conductively isolating from each other the heater and the second total-loss convective chiller using a second thermal barrier while the step of heating the workpiece with the heater, is performed simultaneously with at least one of the step of cooling the workpiece with the first total-loss convective chiller or the step of cooling the workpiece with the second total-loss convective chiller.

10. The method according to claim 6 , wherein:
the step of discharging the first cooling fluid into the central opening is controlled by a first flow restrictor at the first-chiller-channel outlet; and
the step of discharging the second cooling fluid into the central opening is controlled by a second flow restrictor at the second-chiller-channel outlet.

11. The method according to claim 6 , wherein:
the step of discharging the first cooling fluid into the central opening is controlled by a first expansion valve at the first-chiller-channel outlet; and
the step of discharging the second cooling fluid into the central opening is controlled by a second expansion valve at the second-chiller-channel outlet.

12. The method according to claim 8 , wherein the first thermal barrier contacts the first thermal seal.

13. The method according to claim 9 , wherein the second thermal barrier contacts the second thermal seal.

14. The method according to claim 1 , further comprising:
engaging a first end of the workpiece with the first anvil of the high-pressure-torsion apparatus; and
engaging a second end of the workpiece with the second anvil of the high-pressure-torsion apparatus,
wherein the steps of compressing the workpiece along the central axis of the workpiece and twisting the workpiece about the central axis are performed using the first anvil and the second anvil.

15. The method according to claim 14 , wherein:
the first anvil comprises a first-anvil base and a first-anvil protrusion, extending from the first-anvil base toward the second anvil along the working axis;
the annular body comprises a central opening; and
the step of translating the annular body along the working axis of the high-pressure-torsion apparatus comprises advancing the first-anvil protrusion into the central opening of the annular body.

16. The method according to claim 15 , wherein the step of cooling the workpiece with the first total-loss convective chiller is discontinued while advancing the first-anvil protrusion into the central opening of the first total-loss convective chiller.

17. The method according to claim 14 , wherein:
the second anvil comprises a second-anvil base and a second-anvil protrusion, extending from the second-anvil base toward the first anvil along the working axis;
the annular body comprises a central opening; and
the step of

Assignees

• Boeing Co

Inventors

• Verma Ravi

Classifications

• C21D9/0075

  for rods of limited length (of unlimited length C21D9/52) · CPC title

• C21D8/06

  during manufacturing of rods or wires · CPC title

• C21D1/19 Primary

  by interrupted quenching · CPC title

• C21D8/0273

  Final recrystallisation annealing · CPC title

• C21D1/613

  Gases; Liquefied or solidified normally gaseous material · CPC title