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

Patent metadata

Field	Value
Publication number	US-10907228-B2
Application number	US-201816227543-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 conductive chiller, a second conductive chiller, and a heater, positioned between the first conductive chiller and the second conductive chiller along the working axis. The method comprises compressing the workpiece along a central axis of the workpiece and, simultaneously with compressing the workpiece alone 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, the high-pressure-torsion apparatus comprising a working axis, a first anvil, a second anvil, and an annular body, the annular body comprising a first conductive chiller, a second conductive chiller, and a heater, positioned between the first conductive chiller and the second conductive 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
cooling the workpiece with at least one of the first conductive chiller or cooling the workpiece with the second conductive chiller, simultaneously with the step of heating the workpiece with the heater,
wherein:
the step of cooling the workpiece with the first conductive chiller comprises steps of routing a first cooling fluid through the first conductive chiller and transferring heat from the workpiece to the first cooling fluid through a thermal conductor of the first conductive chiller; and
the step of cooling the workpiece with the second conductive chiller comprises steps of routing a second cooling fluid through the second conductive chiller and transferring heat from the workpiece to the second cooling fluid through a second thermal conductor of the second conductive chiller.

2. The method according to claim 1 ,
wherein the step of routing the first cooling fluid through the first conductive chiller and the step of routing the second cooling fluid through the second conductive chiller are independently controlled, and
wherein each of the first cooling fluid and the second cooling fluid is a liquid.

3. The method according to claim 2 , wherein:
the annular body comprises a central opening, at least partially formed by the thermal conductor of the first conductive chiller and the second thermal conductor of the second conductive chiller;
the step of transferring heat from the workpiece to the first cooling fluid through the thermal conductor of the first conductive chiller comprises contacting the workpiece, protruding through the central opening with the thermal conductor of the first conductive chiller; and
the step of transferring heat from the workpiece to the second cooling fluid through the second thermal conductor of the second conductive chiller comprises contacting the workpiece, protruding through the central opening with the second thermal conductor of the second conductive chiller.

4. The method according to claim 3 , wherein:
the first conductive chiller comprises a channel, comprising an inlet, an outlet, and an intermediate portion, which is in fluidic communication with the inlet and the outlet;
the step of transferring heat from the workpiece to the first cooling fluid through the thermal conductor of the first conductive chiller comprises flowing the first cooling fluid from the inlet of the channel, through the intermediate portion of the channel, and into the outlet of the channel; and
the thermal conductor fluidically isolates the intermediate portion of the channel from the central opening of the annular body.

5. The method according to claim 3 , wherein:
the second conductive chiller comprises a second channel, comprising a second inlet, a second outlet, and a second intermediate portion, which is in fluidic communication with the second inlet and the second outlet;
the step of transferring heat from the workpiece to the second cooling fluid through the second thermal conductor of the second conductive chiller comprises flowing the second cooling fluid from the second inlet of the second channel, through the second intermediate portion of the second channel, and into the second outlet of the second channel; and
the second thermal conductor of the second conductive chiller fluidically isolates the second intermediate portion of the second channel from the central opening of the annular body.

6. The method according to claim 1 , wherein:
the step of transferring the heat from the workpiece to the first cooling fluid through the thermal conductor of the first conductive chiller comprises a step of flexing the thermal conductor toward the working axis and directly contacting the workpiece with the thermal conductor; and
the step of transferring the heat from the workpiece to the second cooling fluid through the second thermal conductor of the second conductive chiller comprises a step of flexing the second thermal conductor toward the working axis and directly contacting the workpiece with the second thermal conductor.

7. The method according to claim 6 , wherein:
the step of flexing the thermal conductor toward the working axis comprises routing the first cooling fluid through the first conductive chiller; and
the step of flexing the second thermal conductor toward the working axis comprises routing the second cooling fluid through the second conductive chiller.

8. The method according to claim 1 , wherein each of the first cooling fluid and the second cooling fluid is a liquid.

9. The method according to claim 5 , wherein the second intermediate portion of the second channel has a closed shape and surrounds the working axis.

10. 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 at least one of the first conductive chiller or the second conductive chiller.

11. The method according to claim 10 , 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 conductive chiller or the second conductive chiller.

12. The method according to claim 1 , further comprising thermally conductively isolating the heater from the second conductive chiller from each other using a second thermal barrier while the step of heating the workpiece with the heater is performed simultaneously with the step of cooling the workpiece with the second conductive chiller.

13. The method according to claim 12 , wherein the second thermal barrier contacts the workpiece.

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; and
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 base and a protrusion, extending from the 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 protrusion of the first anvil 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 conductive chiller is discontinued while advancing the protrusion of the first anvil into the central opening of the first conductive chi

Assignees

• Boeing Co

Inventors

• Verma Ravi

Classifications

• C21D2241/01

  under pressure · CPC title

• C21D9/28

  for plain shafts · CPC title

• B21D37/16

  Heating or cooling · CPC title

• C21D1/613

  Gases; Liquefied or solidified normally gaseous material · CPC title

• B21D11/22

  Auxiliary equipment, e.g. positioning devices · CPC title