AL-SI-FE CASTING ALLOYS

Abstract

New aluminum casting (foundry) alloys are disclosed. The new aluminum casting alloys may include from 6.0 to 11.5 wt. % Si, from 0.30 to 0.80 wt. % Fe, optionally from 0.07 to 0.20 wt. % of X, wherein X is selected from the group consisting of Mg, Mo, Zr, and combinations thereof, and optionally 100-500 ppm Sr, the balance being aluminum and unavoidable impurities. The new aluminum casting alloys may be high-pressure die cast into complex shapes. The new aluminum casting alloys may be useful, for instance, in heat sink/antenna applications.

Claims

1. An aluminum casting alloy comprising: from 6.0 to 11.5 wt. % Si; from 0.30 to 0.80 wt. % Fe; optionally from 0.07 to 0.20 wt. % of X, wherein Xis selected from the group consisting of Mg, Mo, Zr, and combinations thereof; and optionally 100-500 ppm Sr; the balance being aluminum and unavoidable impurities.

2. The aluminum casting alloy of claim 1, comprising at least 7.0 wt. % Si, or at least 8.0 wt. % Si, or at least 9.0 wt. % Si, or at least 9.5 wt. % Si.

3. The aluminum casting alloy of claim 1, comprising not greater than 11.0 wt. % Si, or not greater than 10.5 wt. % Si.

4. The aluminum casting alloy of claim 1, comprising at least 0.35 wt. % Fe, or at least 0.40 wt. % Fe, or at least 0.45 wt. % Fe, or at least 0.50 wt. % Fe.

5. The aluminum casting alloy of claim 1, comprising not greater than 0.75 wt. % Fe, or not greater than 0.70 wt. % Fe, or not greater than 0.65 wt. % Fe.

6. The aluminum casting alloy of claim 1, wherein the aluminum casting alloy includes X.

7. The aluminum casting alloy of claim 6, comprising from 0.07 to 0.18 wt. % of X, or from 0.07 to 0.15 wt. % of X, or from 0.07 to 0.12 wt. % of X, or from 0.07 to 0.10 wt. % of X.

8. The aluminum casting alloy of claim 1, wherein the aluminum casting alloy is substantially free of all of Mg, Mo, and Zr, having less than 0.07 wt. % of each of Mg, Mo, and Zr.

9. The aluminum casting alloy of claim 8, comprising not greater than 0.05 wt. % of each of Mg, Mo, and Zr, or not greater than 0.04 wt. % of each of Mg, Mo, and Zr, or not greater than 0.03 wt. % of each of Mg, Mo, and Zr, or not greater than 0.02 wt. % of each of Mg, Mo, and Zr.

10. The aluminum casting alloy of claim 1, wherein the aluminum casting alloy includes Sr.

11. The aluminum casting alloy of claim 1, wherein the aluminum casting alloy includes less than 100 ppm Sr, or not greater than 50 ppm Sr, or not greater than 25 ppm Sr, or not greater than 10 ppm Sr.

12. The aluminum casting alloy of claim 1, wherein the aluminum casting alloys is substantially free of copper, manganese, zinc, titnaium, chromium, nickel, and vanadium.

13. The aluminum casting alloy of claim 12, comprising less than 0.10 wt. % Cu, or not greater than 0.05 wt. % Cu, or not greater than 0.03 wt. % Cu, or not greater than 0.01 wt. % Cu.

14. The aluminum casting alloy of claim 12, comprising not greater than 0.04 wt. % Mn, or not greater than 0.03 wt. % Mn, or not greater than 0.02 wt. % Mn.

15. The aluminum casting alloy of claim 12, comprising less than 0.10 wt. % Zn, or not greater than 0.05 wt. % Zn, or not greater than 0.03 wt. % Zn, or not greater than 0.01 wt. % Zn.

16. The aluminum casting alloy of claim 12, comprising not greater than 0.04 wt. % of each of Ti, Cr, Ni, and V, or not greater than 0.03 wt. % of each of Ti, Cr, Ni, and V, or not greater than 0.02 wt. % of each of Ti, Cr, Ni, and V.

17. The aluminum casting alloy of claim 16, wherein the cummulative amounts of Ti, Cr, Ni, and V do not exceed 0.10 wt. %, or wherein the cummulative amounts of Ti, Cr, Ni, and V do not exceed 0.08 wt. %, or wherein the cummulative amounts of Ti, Cr, Ni, and V do not exceed 0.06 wt. %.

18. A high-pressure die cast product made from the aluminum casting alloy of claim 1.

19. The high-pressure die cast product of claim 18, wherein the product realizes a tensile yield strength of at least 65 MPa and an elongation of at least 2%.

20. The high-pressure die cast product of claim 18, wherein the product realizes a thermal conductivity of at least 160 W/m/° C. at a temperature of 25° C., or at least 170 W/m/° C. at a temperature of 25° C., or at least 175 W/m/° C. at a temperature of 25° C., or at least 180 W/m/° C. at a temperature of 25° C., or at least 185 W/m/° C. at a temperature of 25° C., or at least 190 W/m/° C. at a temperature of 25° C., or at least 195 W/m/° C., or higher, at a temperature of 25° C.

Description

DETAILED DESCRIPTION

EXAMPLE 1

[0025] Six aluminum alloys were directionally solified. The compositons of the alloys are shown in Table 1, below.

TABLE-US-00001 TABLE 1 Alloy Compositions Alloy* Si (wt. %) Fe (wt. %) Sr (ppm) 1 10.7 0.52 170 2 10.5 0.51 — 3 8.6 0.51 — 4 6.7 0.52 — 5 5.0 0.55 20 6 3.1 0.55 — *The balance of the alloys was aluminum and impurities. All alloys contained less than 0.01 wt. % Cu. All alloys contained less than 0.02 wt. % Mn. All alloys contained less than 0.03 wt. % Mg. All alloys contains less than 0.01 wt. % of each of Cr, Ni, Zn, Ti, and Zr. All alloys contained less than 0.02 wt. % of V. The remaining impurities were all less than 0.01 wt. % each.

[0026] The thermal conducity of the alloys was measured at various temperatures, the results of which are shown in Table 2 below. Thermal conductivity may be measured using equation 1 of ASTM E1461 using thermal diffusivity results obtained per ASTM E1461-13, specific heat capacity results obtained per ASTM E1269-11 (2018) and density results per ASTM B311-17.

TABLE-US-00002 TABLE 2 Thermal Conductivity Results Temp. Thermal Conductivity (W/m/° C.) (° C.) Alloy 6 Alloy 5 Alloy 4 Alloy 3 Alloy 2 Alloy 1 25 203 197 196 191 192 190 100 200 195 193 190 191 187 200 201 197 193 190 190 195 300 203 198 191 189 186 180 400 204 201 198 192 185 181 500 221 213 204 202 203 195

[0027] As shown, the alloys realize high thermal conductivity. Further alloys 1-4 are expected to realize good fluidity due to their silicon content. Alloy 1-2 are expected to have excellent fluidity.

[0028] While various embodiments of the present disclosure have been described in detail, it is apparent that modifications and adaptations of those embodiments will occur to those skilled in the art. However, it is to be expressly understood that such modifications and adaptations are within the spirit and scope of the present disclosure.