Additively manufactured single-crystal metallic components, and methods for producing the same

Patent metadata

Field	Value
Publication number	US-12076818-B2
Application number	US-202318106333-A
Country	US
Kind code	B2
Filing date	Feb 6, 2023
Priority date	Oct 4, 2018
Publication date	Sep 3, 2024
Grant date	Sep 3, 2024

Abstract

Some variations provide a method of making an additively manufactured single-crystal metallic component, comprising: providing a feedstock comprising a first metal or metal alloy; providing a build plate comprising a single crystal of a second metal or metal alloy; exposing the feedstock to an energy source for melting the feedstock, generating a melt layer on the build plate; and solidifying the melt layer, generating a solid layer (on the build plate) of a metal component. The solid layer is also a single crystal of the first metal or metal alloy. The method may be repeated many times to build the part. Some variations provide a single-crystal metallic component comprising a plurality of solid layers in an additive-manufacturing build direction, wherein the plurality of solid layers forms a single crystal of a metal or metal alloy with a continuous crystallographic texture. The crystal orientation may vary along the additive-manufacturing build direction.

First claim

What is claimed is:

1. A method of making an additively manufactured single-crystal metallic component, said method comprising:
(a) providing a metal-containing feedstock comprising a first metal or metal alloy, wherein said metal-containing feedstock is in the form of a solid powder, a solid wire, or a combination thereof;
(b) providing a build plate comprising a build region consisting of a seed single crystal of a second metal or metal alloy;
(c) adding a first amount of said metal-containing feedstock to said build plate and then exposing said first amount of said metal-containing feedstock to an energy source for melting said first amount of said metal-containing feedstock, thereby generating a first melt layer disposed on said build region; and
(d) solidifying said first melt layer, thereby generating a first solid layer, disposed on said build region, of an additively manufactured metal component, wherein said first solid layer is a single crystal of said first metal or metal alloy.

2. The method of claim 1 , wherein said metal-containing feedstock is a metal alloy.

3. The method of claim 1 , wherein said first metal or metal alloy is chemically the same as said second metal or metal alloy.

4. The method of claim 1 , wherein said seed single crystal is in a crystal orientation selected from crystal lattice planes (100), (110), (111), or an angle between two of said crystal lattice planes (100), (110), and (111).

5. The method of claim 1 , wherein said build plate comprises an exterior layer that consists of said seed single crystal of said second metal or metal alloy.

6. The method of claim 1 , wherein said build plate consists of said seed single crystal.

7. The method of claim 1 , wherein said energy source is a laser-diode energy source.

8. The method of claim 1 , wherein step (c) utilizes an exposure time from 1 microsecond to 1 minute.

9. The method of claim 1 , wherein step (c) is controlled to maintain an average thermal gradient from 10 K/m to 10 6 K/m within said first melt layer.

10. The method of claim 1 , wherein step (d) is controlled to maintain an average thermal gradient below 10 6 K/m within said first solid layer.

11. The method of claim 1 , wherein step (d) is controlled to maintain an average solidification velocity from 10 −7 m/s to 1 m/s within said first solid layer.

12. The method of claim 1 , wherein step (c) utilizes a controlled exposure pattern that spatially constrains solidification in step (d).

13. The method of claim 1 , wherein said first solid layer is in a crystal orientation selected from crystal lattice planes (100), (110), (111), or an angle between two of said crystal lattice planes (100), (110), and (111).

14. The method of claim 1 , said method further comprising repeating steps (b) and (c) a plurality of times to generate a plurality of solid layers by sequentially solidifying a plurality of melt layers in an additive-manufacturing build direction, wherein said plurality of solid layers is a final single crystal of said first metal or metal alloy.

15. The method of claim 14 , wherein said final single crystal is in a crystal orientation selected from crystal lattice planes (100), (110), (111), or an angle between two of said crystal lattice planes (100), (110), and (111).

16. The method of claim 14 , wherein said final single crystal, on length scales of 100 μm along said additive-manufacturing build direction, contains crystallographic misorientations that are less than 5 degrees on average.

17. The method of claim 1 , wherein said seed single crystal and said first solid layer form one continuous crystal.

18. The method of claim 14 , wherein said seed single crystal and said final single crystal form one continuous crystal.

19. The method of claim 1 , wherein said method further comprises separating said build plate from said additively manufactured single-crystal metallic component.

20. The method of claim 19 , wherein said final single crystal does not have a crystallographic discontinuity at a surface arising from said separating said build plate from said additively manufactured single-crystal metallic component.

Assignees

• Hrl Lab Llc

Inventors

• Martin John H
• Hundley Jacob M
• Yahata Brennan D

Classifications

• B22F2999/00

  Aspects linked to processes or compositions used in powder metallurgy · CPC title

• C30B29/68

  Crystals with laminate structure, e.g. "superlattices" · CPC title

• B22F3/1028

  Controlled cooling · CPC title

• B33Y70/00

  Materials specially adapted for additive manufacturing · CPC title

• C30B29/52

  Alloys · CPC title