Methods of forming a workpiece made of a naturally aging alloy

Patent metadata

Field	Value
Publication number	US-9719150-B2
Application number	US-201514589545-A
Country	US
Kind code	B2
Filing date	Jan 5, 2015
Priority date	Jan 5, 2015
Publication date	Aug 1, 2017
Grant date	Aug 1, 2017

Abstract

A method of forming a workpiece having an initial heat treatment and made of a naturally aging alloy to a final shape using an incremental sheet forming (ISF) machine having a coordinate system and a tool path corresponding to the final shape of the workpiece is disclosed. The method comprises positioning the workpiece in the ISF machine; performing an initial forming operation on the workpiece using the ISF machine; performing a final heat treatment on the workpiece; repositioning the workpiece in the ISF machine; and, with the workpiece in a final workpiece orientation in the ISF machine and the tool path of the ISF machine in a final tool-path orientation in the ISF machine, performing a final forming operation on the workpiece using the ISF machine to achieve the final shape of the workpiece. Intermediate heat treatments and intermediate forming operations in the ISF machine may also be performed.

First claim

What is claimed is:

1. A method of forming a workpiece made of a naturally aging alloy to a final shape, the method comprising:
providing an ISF machine having a coordinate system and a tool path corresponding to the final shape of the workpiece;
performing an initial heat treatment on the workpiece;
positioning the workpiece in the ISF machine in an initial workpiece orientation in the coordinate system of the ISF machine;
with the workpiece in the initial workpiece orientation in the coordinate system of the ISF machine and the tool path of the ISF machine in an initial tool-path orientation in the coordinate system of the ISF machine, performing an initial forming operation on the workpiece using the ISF machine;
performing a final heat treatment on the workpiece;
repositioning the workpiece in the ISF machine in a final workpiece orientation in the coordinate system of the ISF machine; and
with the workpiece in the final workpiece orientation in the coordinate system of the ISF machine and the tool path of the ISF machine in a final tool-path orientation in the coordinate system of the ISF machine, performing a final forming operation on the workpiece using the ISF machine to achieve the final shape of the workpiece.

2. The method according to claim 1 , wherein performing the initial heat treatment on the workpiece comprises one of:
mill annealing and cooling the workpiece or
solution annealing and quenching the workpiece.

3. The method according to claim 1 , wherein, when the initial heat treatment on the workpiece comprises solution annealing and quenching the workpiece, performing the initial forming operation on the workpiece using the ISF machine comprises performing the initial forming operation within an initial predetermined time period after quenching the workpiece.

4. The method according to claim 1 , wherein performing the final heat treatment on the workpiece comprises solution annealing and quenching the workpiece.

5. The method according to claim 4 , wherein performing the final heat treatment on the workpiece creates residual stresses in the workpiece, the method further comprising elongating at least a portion of the workpiece a predetermined amount when performing the final forming operation on the workpiece.

6. The method according to claim 1 , wherein the final workpiece orientation of the workpiece in the coordinate system of the ISF machine is identical to the initial workpiece orientation of the workpiece in the coordinate system of the ISF machine.

7. The method according to claim 1 , wherein the final workpiece orientation of the workpiece in the coordinate system of the ISF machine is different from the initial workpiece orientation of the workpiece in the coordinate system of the ISF machine.

8. The method according to claim 1 , further comprising:
performing an intermediate heat treatment on the workpiece after performing the initial forming operation on the workpiece using the ISF machine;
repositioning the workpiece in the ISF machine in an intermediate workpiece orientation in the coordinate system of the ISF machine; and
with the workpiece in the intermediate workpiece orientation in the coordinate system of the ISF machine and the tool path of the ISF machine in an intermediate tool-path orientation in the coordinate system of the ISF machine, performing an intermediate forming operation on the workpiece using the ISF machine, before performing the final heat treatment on the workpiece, to achieve an intermediate shape of the workpiece.

9. The method according to claim 8 , wherein performing the intermediate heat treatment on the workpiece comprises one of:
mill annealing and cooling the workpiece or
solution annealing and quenching the workpiece.

10. The method according to claim 1 , further comprising, after performing the initial forming operation on the workpiece in the ISF machine and before performing the final heat treatment on the workpiece:
performing intermediate heat treatments; and
performing intermediate forming operations on the workpiece in the ISF machine,
wherein the intermediate heat treatments and the intermediate forming operations alternate with each other.

11. The method according to claim 10 , wherein performing the intermediate heat treatments comprises at least one of:
mill annealing and cooling the workpiece or
solution annealing and quenching of workpiece.

12. A method of forming a workpiece made of a naturally aging alloy to a final shape, the workpiece having an initial heat treatment, the method comprising:
providing an ISF machine having a coordinate system and a tool path corresponding to the final shape of the workpiece;
positioning the workpiece in the ISF machine in an initial workpiece orientation in the coordinate system of the ISF machine;
with the workpiece in the initial workpiece orientation in the coordinate system of the ISF machine and the tool path of the ISF machine in an initial tool-path orientation in the coordinate system of the ISF machine, performing an initial forming operation on the workpiece using the ISF machine;
performing a final heat treatment on the workpiece;
repositioning the workpiece in the ISF machine in a final workpiece orientation in the coordinate system of the ISF machine; and
with the workpiece in the final workpiece orientation in the coordinate system of the ISF machine and the tool path of the ISF machine in a final tool-path orientation in the coordinate system of the ISF machine, performing a final forming operation on the workpiece using the ISF machine to achieve the final shape of the workpiece.

13. The method according to claim 12 , wherein performing the final heat treatment on the workpiece comprises solution annealing and quenching the workpiece.

14. The method according to claim 13 , wherein performing the final heat treatment on the workpiece creates residual stresses in the workpiece, the method further comprising elongating at least a portion of the workpiece a predetermined amount when performing the final forming operation on the workpiece.

15. The method according to claim 12 , wherein the final workpiece orientation of the workpiece in the coordinate system of the ISF machine is identical to the initial workpiece orientation of the workpiece in the coordinate system of the ISF machine.

16. The method according to claim 12 , wherein the final workpiece orientation of the workpiece in the coordinate system of the ISF machine is different from the initial workpiece orientation of the workpiece in the coordinate system of the ISF machine.

17. The method according to claim 12 , further comprising:
performing an intermediate heat treatment on the workpiece after performing the initial forming operation on the workpiece using the ISF machine;
repositioning the workpiece in the ISF machine in an intermediate workpiece orientation in the coordinate system of the ISF machine; and
with the workpiece in the intermediate workpiece orientation in the coordinate system of the ISF machine and the tool path of the ISF machine in an intermediate tool-path orientation in the coordinate system of the ISF machine, performing an intermediate forming operation on the workpiece using the ISF machine, before performing the final heat treatment on the workpiece, to achieve an intermediate shape of the workpiece.

18. The method according to claim 17 , wherein, when the intermediate heat treatment on the workpiece comprises solution annealing and quenching the workpiece, performing the intermediate forming operation on the w

Assignees

• Boeing Co

Inventors

• Slattery Kevin Thomas

Classifications

• C22F1/04 Primary

  of aluminium or alloys based thereon · CPC title

• B21D31/00 Primary

  Other methods for working sheet metal, metal tubes, metal profiles (deforming one surface of tubes helically by rolling B21H3/00; upsetting B21J5/08; working metal by removing material therefrom B23; embossing B44B) · CPC title

• C22F1/00

  Changing the physical structure of non-ferrous metals or alloys by heat treatment or by hot or cold working (apparatus for mechanical working of metal B21, B23, B24) · CPC title

• C22F1/002

  by rapid cooling or quenching; cooling agents used therefor · CPC title

• C21D8/02

  during manufacturing of plates or strips (C21D8/12 takes precedence) · CPC title