Advanced cast aluminum alloys for automotive engine application with superior high-temperature properties

Patent metadata

Field	Value
Publication number	US-11713500-B2
Application number	US-202016943359-A
Country	US
Kind code	B2
Filing date	Jul 30, 2020
Priority date	Jul 28, 2017
Publication date	Aug 1, 2023
Grant date	Aug 1, 2023

Abstract

A process of heat treating an Al—Si—Cu—Mg—Fe—Zn—Mn—Sr-TMs alloy, where the TMs include Zr and V, includes heat treating the alloy to produce a microstructure having a matrix with Zr and V in solid solution after solidification. The solid solution Zr, in wt. %, is at least 0.16%, the solid solution V, in wt. %, is at least 0.20% after heat treatment, and Cu and Mg are dissolved into the matrix during the heat treatment and subsequently precipitated during the heat treatment. The composition of the alloy, in wt. %, includes Cu between 3.0-3.5%, Fe between 0-0.2%, Mg between 0.24-0.35%, Mn between 0-0.40%, Si between 6.5-8.0%, Sr between 0-0.025%, Ti between 0.05-0.2%, V between 0.20-0.35%, Zr between 0.2-0.4%, maximum 0.5% total of other alloying elements, and balance Al.

First claim

What is claimed is:

1. A process of heat treating an Al—Si—Cu—Mg—Fe—Zn—Mn—Sr-transition metals (TMs) alloy, wherein the TMs include Zr and V, the process comprising heat treating the alloy to produce a microstructure having a matrix with:
Zr and V in solid solution after solidification;
solid solution Zr, in wt. %, of at least 0.16% and solid solution V, in wt. %, of at least 0.20% after heat treatment; and
Cu and Mg dissolved into the matrix during the heat treatment and subsequently precipitated during the heat treatment.

2. The process according to claim 1 , wherein the composition of the alloy, in wt. %, comprises:
Cu between 3.0-3.5%;
Fe between 0-0.2%;
Mg between 0.24-0.35%;
Mn between 0-0.40%;
Si between 6.5-8.0%;
Sr between 0-0.025%;
Ti between 0.05-0.2%;
V between 0.20-0.35%;
Zr between 0.2-0.4%;
maximum 0.5% total of other alloying elements; and
balance Al,
and the alloy is formed by semi-permanent mold casting followed by the heat treating of the alloy, wherein the heat treating is a three-stage heat treatment.

3. The process according to claim 2 , wherein:
the Cu is between 3.2-3.5%;
the Mg is between 0.24-0.28%;
the Mn is between 0-0.15%;
the Si is between 7.2-7.7%;
the Ti is between 0.08-0.1%;
the V is between 0.22-0.28%; and
the Zr is between 0.33-0.38%.

4. The process according to claim 3 , wherein:
the Cu is 3.4%;
the Fe is 0%;
the Mg is 0.25%;
the Mn is 0%;
the Si is 7.5%;
the Sr is 0%;
the Ti is 0.1%;
the V is 0.25%; and
the Zr is 0.35%.

5. The process according to claim 2 , wherein the three-stage heat treatment comprises:
375° C. for 6 hours, during which the Cu and Mg are dissolved;
495° C. for 0.5 hours, during which the Cu and Mg are further dissolved; and
230° C. for 3 hours, during which the Cu and Mg are precipitated.

6. The process according to claim 1 , wherein the composition of the alloy, in wt. %, comprises:
Cu between 3.0-3.5%;
Fe between 0.2-1.3%;
Mg between 0.24-0.35%;
Mn between 0-0.8%;
Si between 8.0-12.0%;
Ti between 0.05-0.2%;
V between 0.20-0.35%;
Zn between 0-3.0%;
Zr between 0.2-0.4%;
maximum 0.5% total of other alloying elements; and
balance Al,
and the alloy is formed by high-pressure die casting followed by the heat treating of the alloy, wherein the heat treating is a single-stage T5 heat treatment.

7. The process according to claim 6 , wherein:
the Cu is between 3.2-3.5;
the Fe is between 0.20-1.0;
the Mg is between 0.24-0.28;
the Mn is between 0.35-0.50;
the Si is between 9.0-11.0;
the Ti is between 0.08-0.10;
the V is between 0.22-0.28;
the Zn is between 0-1.5; and
the Zr is between 0.33-0.38.

8. The process according to claim 7 , wherein:
the Cu is 3.4%;
the Fe is 0.25%;
the Mg is 0.25%;
the Mn is 0.40%;
the Si is 9.5%;
the Ti is 0.10%;
the V is 0.25%;
the Zn is 0%; and
the Zr is 0.35%.

9. The process according to claim 6 , wherein the single-stage T5 heat treatment comprises 205° C. for 4 hours, during which the Zr, in wt. %, is maintained in the matrix to at least 0.16% and the V, in wt. %, is maintained in the matrix to at least 0.20%, and the Cu and Mg are precipitated.

10. The process according to claim 1 , wherein the alloy is capable of withstanding up to 98 MPa at up to 10 7 cycles at up to 180° C. after 100 hours soaking at a test temperature.

11. A process of heat treating a high fatigue aluminum alloy with a composition, in wt. %, of Cu between 3.0-3.5%, Fe between 0-1.3%, Mg between 0.24-0.35%, Mn between 0-0.8%, Si between 6.5-12.0%, Sr between 0-0.025%, Ti between 0.05-0.2%, V between 0.20-0.35%, Zn between 0-3.0%, Zr between 0.2-0.4%, maximum 0.5% other alloying elements, and the balance Al, the process comprising:
heat treating the alloy to produce a microstructure having a matrix with:
Zr and V in solid solution after solidification;
solid solution Zr of at least 0.16% and solid solution V of at least 0.20% after heat treatment; and
Cu and Mg dissolved into the matrix during the heat treatment and subsequently precipitated during the heat treatment.

12. The process according to claim 11 , wherein the heat treatment is a three-stage heat treatment comprising:
375° C. for 6 hours, during which the Cu and Mg are dissolved;
495° C. for 0.5 hours, during which the Cu and Mg are further dissolved; and
230° C. for 3 hours, during which the Cu and Mg are precipitated.

13. The process according to claim 12 , wherein:
the Cu is between 3.2-3.5%;
the Mg is between 0.24-0.28%;
the Mn is between 0-0.15%;
the Si is between 7.2-7.7%;
the Ti is between 0.08-0.1%;
the V is between 0.22-0.28%; and
the Zr is between 0.33-0.38%.

14. The process according to claim 13 , wherein:
the Cu is 3.4%;
the Fe is 0%;
the Mg is 0.25%;
the Mn is 0%;
the Si is 7.5%;
the Sr is 0%;
the Ti is 0.1%;
the V is 0.25%; and
the Zr is 0.35%.

15. The process according to claim 11 , wherein:
the Cu is 3.0-3.5%;
the Fe is 0.2-1.3%;
the Mg is 0.24-0.35%;
the Mn is 0-0.8%;
the Si is 8.0-12.0%;
the Ti is 0.05-0.2%;
the V is 0.20-0.35%;
the Zn is 0-3.0%;
the Zr is 0.2-0.4%;
maximum 0.5% total of other elements; and
balance Al,
and the alloy is formed by high-pressure die casting followed by the heat treating, and the heat treating is a single-stage T5 heat treatment.

16. The process according to claim 15 , wherein:
the Cu is between 3.2-3.5;
the Fe is between 0.20-1.0;
the Mg is between 0.24-0.28;
the Mn is between 0.35-0.50;
the Si is between 9.0-11.0;
the Ti is between 0.08-0.10;
the V is between 0.22-0.28;
the Zn is between 0-1.5; and
the Zr is between 0.33-0.38.

17. The process according to claim 16 , wherein:
the Cu is 3.4%;
the Fe is 0.25%;
the Mg is 0.25%;
the Mn is 0.40%;
the Si is 9.5%;
the Ti is 0.10%;
the V is 0.25%;
the Zn is 0%; and
the Zr is 0.35%.

18. The process according to claim 15 , wherein the single-stage T5 heat treatment comprises 205° C. for 4 hours, during which the Zr is maintained in the matrix to at least 0.16% and the V is maintained in the matrix to at least 0.20%, and the Cu and Mg are precipitated.

19. The process according to claim 11 , wherein the alloy is capable of withstanding up to 98 MPa at up to 10 7 cycles at up to 180° C. after 100 hours soaking at a test temperature.

20. A process of heat treating a high fatigue aluminum alloy with a composition, in wt. %, of Cu between 3.0-3.5%, Fe between 0-1.3%, Mg between 0.24-0.35%, Mn between 0-0.8%, Si between 6.5-12.0%, Sr between 0-0.025%, Ti between 0.05-0.2%, V between 0.20-0.35%, Zn between 0-3.0%, Zr between 0.2-0.4%, maximum 0.5% other elements, and the balance Al, the process comprising:
heat treating the alloy to produce a microstructure having a matrix with:
Zr and V in solid solution after solidification;
solid solution Zr of at least 0.16% and solid solution V of at least 0.20% after heat treatment; and
Cu and Mg dissolved into the matrix during the heat treatment and subsequently precipitated during the heat treatment, wherein the heat treatment is selected from the group consisting of a three-stage heat treatment and a single-stage T5 heat treatment, wherein:
the three-stage heat treatment comprises 375° C. for 6 hours during which the Cu and Mg are dissolved, 495° C. for 0.5 hours during which the Cu and Mg are further dissolved, and 230° C. for 3 hours, during which the Cu and Mg are precipitated;
the single-stage T5 heat treatment comprises 205° C. for 4 hours during which

Assignees

• Ford Global Tech Llc

Inventors

• Li Mei
• Zindel Jacob Wesley
• Godlewski Larry Alan
• Ghaffari Bita
• Huo Yang
• Engler-Pinto Carlos
• Lai Wei-Jen

Classifications

• C22F1/043 Primary

  of alloys with silicon as the next major constituent · CPC title

• B22D21/007

  with low melting point, e.g. Al 659 degrees C, Mg 650 degrees C · CPC title

• C22C21/02 Primary

  with silicon as the next major constituent · CPC title

• C22C21/04

  Modified aluminium-silicon alloys · CPC title

• F02F1/00

  Cylinders; Cylinder heads · CPC title