Aluminum alloys having iron and rare earth elements

Patent metadata

Field	Value
Publication number	US-2020056268-A1
Application number	US-201916548225-A
Country	US
Kind code	A1
Filing date	Aug 22, 2019
Priority date	Apr 13, 2017
Publication date	Feb 20, 2020
Grant date	—

Abstract

New aluminum alloys having iron and one or more rare earth elements are disclosed. The new alloys may include from 1 to 15 wt. % Fe and from 1 to 20 wt. % of the rare earth element(s), the balance aluminum and any optional incidental elements and impurities. The new aluminum alloys may be produced via additive manufacturing techniques.

First claim

What is claimed is:

1 . A method comprising:
(a) using a feedstock in an additive manufacturing apparatus, wherein the feedstock comprises an alloy having:
from 1 to 15 wt. % Fe; and
from 1 to 20 wt. % of at least one rare earth (RE) element,
wherein RE (wt. %)≥−3.11(wt. % Fe)+13.4; and/or

wherein RE (wt. %)≤−3.11(wt. % Fe)+38;

the balance being aluminum and any optional incidental elements and impurities; and
(b) producing an additively manufactured body in the additive manufacturing apparatus using the feedstock, wherein the additively manufactured body comprises at least 10-40 vol. % of Al—Fe-RE intermetallics.

2 . The method of claim 1 , wherein the additively manufactured body comprises not greater than 20 vol. % of large Al—Fe-RE spheroid particles.

3 . The method of claim 1 , wherein the additively manufactured body realizes a fine eutectic-type microstructure.

4 . The method of claim 3 , wherein the fine eutectic-type microstructure comprises at least one of spheroidal, cellular, lamellar, wavy, and brick structures.

5 . The method of claim 4 , wherein an average spacing between eutectic structures is not greater than 5 micrometers

6 . The method of claim 1 , wherein the feedstock comprises 5-11 wt. % Fe and 2.5-10 wt. % of the at least one rare earth element.

7 . The method of claim 1 , wherein the (wt. % Fe) plus the (wt. % of the at least one rare earth (RE) element) is at least 9 wt. %.

8 . The method of claim 1 , wherein the aluminum alloy body realizes a tensile yield strength-to-elongation relationship satisfying the following empirical relationship as measured at 230° C.:
TYS≥−5.0808*(elongation) 2 +22.274*(elongation)+337.08,

when annealed at 300° C. for 24 hours followed by thermal exposure at 230° C. for 1000 hours.

9 . The method of claim 1 , wherein the aluminum alloy product is in the form of an engine component for an aerospace or automotive vehicle, wherein the method comprises:
incorporating the engine component into the aerospace or automotive vehicle; and operating the aerospace or automotive vehicle.

10 . The method of claim 9 , wherein the aluminum alloy product is a compressor wheel for a turbocharger.

11 . The method of claim 1 , wherein:
RE(wt. %)≥−3.11(wt. % Fe)+18; and
RE (wt. %)≤−3.11(wt. % Fe)+34.75.

12 . An additively manufactured aluminum alloy product comprising:
from 1 to 15 wt. % Fe; and from 1 to 20 wt. % of at least one rare earth (RE) element,
wherein RE (wt. %)≥−3.11(wt. % Fe)+13.4; and/or

wherein RE (wt. %)≤−3.11(wt. % Fe)+38;

the balance being any optional incidental elements and impurities, wherein the additively manufactured aluminum alloy product comprises a fine eutectic-type microstructure, wherein the fine eutectic-type microstructure comprises at least one of spheroidal, cellular, lamellar, wavy, and brick structures, and wherein an average spacing between eutectic structures is not greater than 5 micrometers

13 . The additively manufactured aluminum alloy product of claim 12 , wherein the additively manufactured aluminum alloy product comprises 5-11 wt. % Fe and 2.5-10 wt. % of the at least one rare earth element, and wherein the (wt. % Fe) plus the (wt. % of the at least one rare earth (RE) element) is at least 9 wt. %.

14 . The additively manufactured aluminum alloy product of claim 12 , wherein the additively manufactured aluminum alloy product comprises 10-40 vol. % of Al—Fe-RE intermetallics.

15 . The additively manufactured aluminum alloy product of claim 12 , wherein the additively manufactured aluminum alloy product comprises not greater than 20 vol. % of large Al—Fe-RE spheroid particles.

16 . The additively manufactured aluminum alloy product of claim 12 , wherein the additively manufactured aluminum alloy product realizes a tensile yield strength-to-elongation relationship satisfying the following empirical relationship as measured at 230° C.:
TYS≥−5.0808*(elongation) 2 +22.274*(elongation)+337.08,

when annealed at 300° C. for 24 hours followed by thermal exposure at 230° C. for 1000 hours.

17 . The additively manufactured aluminum alloy product of claim 12 , wherein the additively manufactured aluminum alloy product is free of grain refiners.

18 . The additively manufactured aluminum alloy product of claim 17 , wherein the additively manufactured aluminum alloy product comprises columnar grains.

19 . The additively manufactured aluminum alloy product of claim 12 , wherein the additively manufactured aluminum alloy includes from 0.1 to 5 wt. % of one or more grain refiners.

20 . The additively manufactured aluminum alloy product of claim 19 , wherein the additively manufactured aluminum alloy product comprises equiaxed grains having an average grain size of from 0.05 to 50 microns.

Assignees

• Arconic Inc

Inventors

• Heard David W
• Lin Jen C
• Karabin Lynette M
• Yanar Cagatay
• Gu Yijia
• Askin Albert L
• Tang Zhi
• Kulovits Andreas

Classifications

• C22C21/00 Primary

  Alloys based on aluminium · CPC title

• B33Y80/00

  Products made by additive manufacturing · CPC title

• B33Y10/00

  Processes of additive manufacturing · CPC title

• C22F1/04

  of aluminium or alloys based thereon · CPC title

• B29C64/153

  using layers of powder being selectively joined, e.g. by selective laser sintering or melting · CPC title