WO2019245784A1

WO2019245784A1 - Improved aluminum alloy products and methods for making the same

Info

Publication number: WO2019245784A1
Application number: PCT/US2019/036386
Authority: WO
Inventors: Andreas Kulovits; Men Glenn Chu; Lynette M. Karabin
Original assignee: Arconic Inc.
Priority date: 2018-06-20
Filing date: 2019-06-10
Publication date: 2019-12-26

Abstract

New aluminum alloy products are disclosed. The new aluminum alloy products generally include (a) 1 - 15 wt. % of Class A metals, wherein the Class A metals comprise at least one of manganese (Mn), iron (Fe), cobalt (Co) and nickel (Ni), (b) 1 - 20 wt. % of rare earth elements, (c) and 0.1 - 5 wt. % of Class X metals, wherein the Class X metals comprise at least one of titanium (Ti), zirconium (Zr), hafnium (Hf), scandium (Sc), vanadium (V), molybdenum (Mo), niobium (Nb), tantalum (Ta), tungsten (W) and chromium (Cr). The balance of the new aluminum alloys may be aluminum, any optional incidental elements and impurities. The new aluminum alloy product comprises Al-A-RE-X intermetallics, which intermetallics may facilitate grain formation / nucleation.

Description

IMPROVED ALUMINUM ALLOY PRODUCTS AND METHODS FOR MAKING

THE SAME

FIELD OF THE DISCLOSURE

[001] The present disclosure generally relates to new aluminum alloy products and methods of making the same.

BACKGROUND

[002] Aluminum alloy products are generally produced via either shape casting or wrought processes. Shape casting generally involves casting a molten aluminum alloy into its final form, such as via pressure-die, permanent mold, green- and dry-sand, investment, and plaster casting. Wrought products are generally produced by casting a molten aluminum alloy into ingot or billet. The ingot or billet is generally further hot worked, sometimes with cold work, to produce its final form.

SUMMARY OF THE INVENTION

[003] Broadly, the present disclosure relates to new aluminum alloy products and methods of making the same. The new aluminum alloy products generally comprise (and in some instances consist of or consist essentially of) 1 - 15 wt. % of Class A metals, 1 - 20 wt. % of rare earth elements, and 0.1 - 5 wt. % of Class X metals, where the aluminum alloy product comprises Al-A-RE-X intermetallics. The balance of the new aluminum alloy products may be aluminum, any optional incidental elements and impurities. The Class A metals generally comprise at least one of manganese (Mn), iron (Fe), cobalt (Co) and nickel (Ni). The term Class A metals can include a single metal. In one embodiment, the Class A metals are selected from the group consisting of manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni) and combinations thereof. The Class X metals generally comprise at least one of titanium (Ti), zirconium (Zr), hafnium (Hf), scandium (Sc), vanadium (V), molybdenum (Mo), niobium (Nb), tantalum (Ta), tungsten (W), and chromium (Cr). The term Class X metals can include a single metal. In one embodiment, the Class X metals are selected from the group consisting of titanium (Ti), zirconium (Zr), hafnium (Hf), scandium (Sc), vanadium (V), molybdenum (Mo), niobium (Nb), tantalum (Ta), tungsten (W), chromium (Cr) and combinations thereof. “Al-A-RE-X intermetallics” are intermetallic compounds having aluminum, at least one rare earth (RE) element, at least one Class A metal, and at least one Class X metal. One non limiting example of Al-A-RE-X intermetallic compounds are Al-Fe-(Ce,La)-Ti type compounds. Other Al-A-RE-X intermetallic compounds may be used. The new aluminum alloy products may realize an improved combination of properties. The new aluminum alloy products may be crack-free. i. Composition

a. Class X metals

[004] As noted above, the new aluminum alloy products generally comprise 0.1 - 5 wt. % of Class X metals. In one embodiment, a new aluminum alloy product includes at least 0.5 wt. % of the Class X metals. In another embodiment, a new aluminum alloy product includes at least 0.75 wt. % of the Class X metals. In yet another embodiment, a new aluminum alloy product includes 1.0 wt. % of the Class X metals. In another embodiment, a new aluminum alloy product includes at least 1.5 wt. % of the Class X metals. In yet another embodiment, a new aluminum alloy product includes 2.0 wt. % of the Class X metals. In another embodiment, a new aluminum alloy product includes at least 2.5 wt. % of the Class X metals. In yet another embodiment, a new aluminum alloy product includes 3.0 wt. % of the Class X metals. In another embodiment, a new aluminum alloy product includes at least 3.5 wt. % of the Class X metals. In yet another embodiment, a new aluminum alloy product includes 4.0 wt. % of the Class X metals. In another embodiment, a new aluminum alloy product includes at least 4.5 wt. % of the Class X metals

[005] In one embodiment, the amount of the Class X metals exceeds its solubility limit in a new aluminum alloy product. The solubility limit is calculated at the peritectic temperature of a particular Class X metal(s) involved using a binary phase diagram. For instance, if titanium is used as the Class X metal, the solubility limit is the peritectic composition, which is indicated at the peritectic temperature per the aluminum-titanium binary phase diagram. Exceeding the solubility limit of the Class X metals may facilitate production of the Al-A- RE-X intermetallics. In one embodiment, Al-A-RE-X intermetallics form prior to the formation of FCC aluminum grains. As discussed in greater detail below, Al-A-RE-X intermetallics that form prior to the formation of FCC aluminum grains may facilitate the nucleation of FCC aluminum grains. In one embodiment, the aluminum alloy product comprises an amount of the Class X metals that is sufficient to realize at least 10 vol. % of Al-A-RE-X intermetallics.

[006] In one embodiment, the Class X metals comprise at least titanium. In another embodiment, the Class X metals comprise at least zirconium. In yet another embodiment, the Class X metals comprise both titanium and zirconium. In another embodiment, the Class X metal is titanium. In yet another embodiment, the Class X metal is zirconium. b. Class A Metals and Rare Earth Elements

[007] As noted above, the new aluminum alloy products generally comprise 1 - 15 wt. % of Class A metals and 1 - 20 wt. % of rare earth elements. In one embodiment, the new aluminum alloy products comprise 3-11 wt. % of the Class A metals and 2.5-10 wt. % of the rare earth elements. In another embodiment, the new aluminum alloy products comprise 5-11 wt. % of the Class A metals and 2.5-10 wt. % of the rare earth elements.

[008] The rare earth elements comprise at least one of yttrium and any of the fifteen lanthanides elements. The lanthanides are the fifteen metallic chemical elements with atomic numbers 57 through 71, from lanthanum through lutetium. The term rare earth elements can include one rare earth element. In one embodiment, the Class A metals at least include iron. In one embodiment, the rare earth elements include at least one of cerium, lanthanum and mixtures thereof. In one embodiment, the Class A metal is iron, and the rare earth elements are cerium, lanthanum and mixtures thereof. In one embodiment, a new aluminum alloy product comprises an amount of the Class A metal(s) and the rare earth element(s) sufficient to realize at least 10 vol. % of Al-A-RE-X intermetallics.

[009] In one embodiment, a new aluminum alloy product includes at least 2 wt. % of the Class A metal(s). The one or more Class A metals may facilitate, inter alia , high strength. In another embodiment, a new aluminum alloy product includes at least 3 wt. % Class A metal(s). In yet another embodiment, a new aluminum alloy product includes at least 4 wt. % Class A metal(s). In another embodiment, a new aluminum alloy product includes at least 5 wt. % Class A metal(s). In yet another embodiment, a new aluminum alloy product includes at least 6 wt. % Class A metal(s). In another embodiment, a new aluminum alloy product includes at least 7 wt. % Class A metal(s). In yet another embodiment, a new aluminum alloy product includes at least 7.5 wt. % Class A metal(s). In one embodiment, a new aluminum alloy product includes not greater than 14 wt. % Class A metal(s). In another embodiment, a new aluminum alloy product includes not greater than 13 wt. % Class A metal(s). In yet another embodiment, a new aluminum alloy product includes not greater than 12 wt. % Class A metal(s). In another embodiment, a new aluminum alloy product includes not greater than 11 wt. % Class A metal(s). In yet another embodiment, a new aluminum alloy product includes not greater than 10 wt. % Class A metal(s). In another embodiment, a new aluminum alloy product includes not greater than 9 wt. % Class A metal(s). In yet another embodiment, a new aluminum alloy product includes not greater than 8 wt. % Class A metal(s). In another embodiment, a new aluminum alloy product includes not greater than 7 wt. % Class A metal(s). In yet another embodiment, a new aluminum alloy product includes not greater than 6 wt. % Class A metal(s).

[0010] In one approach, a new aluminum alloy product includes from 1 to 20 wt. % of the rare earth elements. The use of rare earth element(s) facilitates, inter alia , thermal stability. In one embodiment, a new aluminum alloy product includes at least 1.5 wt. % rare earth element(s). In another embodiment, an alloy includes at least 2 wt. % rare earth element(s). In yet another embodiment, a new aluminum alloy product includes at least 2.5 wt. % rare earth element(s). In yet another embodiment, a new aluminum alloy product includes at least 3 wt. % rare earth element(s). In another embodiment, a new aluminum alloy product includes at least 4 wt. % rare earth element(s). In yet another embodiment, a new aluminum alloy product includes at least 5 wt. % rare earth element(s). In another embodiment, a new aluminum alloy product includes at least 6 wt. % rare earth element(s). In one embodiment, a new aluminum alloy product includes not greater than 17.5 wt. % rare earth element(s). In another embodiment, a new aluminum alloy product includes not greater than 15 wt. % rare earth element(s). In yet another embodiment, a new aluminum alloy product includes not greater than 12.5 wt. % rare earth element(s). In another embodiment, an alloy includes not greater than 12 wt. % rare earth element(s). In yet another embodiment, a new aluminum alloy product includes not greater than 11 wt. % rare earth element(s). In another embodiment, a new aluminum alloy product includes not greater than 10 wt. % rare earth element(s). In yet another embodiment, a new aluminum alloy product includes not greater than 9 wt. % rare earth element(s). In another embodiment, a new aluminum alloy product includes not greater than 8 wt. % rare earth element(s). In yet another embodiment, a new aluminum alloy product includes not greater than 7 wt. % rare earth element(s). In another embodiment, a new aluminum alloy product includes not greater than 6 wt. % rare earth element(s).

[0011] Non-limiting examples of useful aluminum alloy compositions (Alloys 1-6) are given in Table 1, below.

Table 1: Example Aluminum Alloys

[0012] In some embodiments, Alloy 1 from Table 1 includes 2.5-6.5 wt. % of rare earth elements, wherein the 2.5-6.5 wt. % of rare earth elements comprise 2.0-4.0 wt. % Ce and 0.5-2.5 wt. % La. In some embodiments, Alloy 2 from Table 1 includes 2.8-5.3 wt. % of rare earth elements, wherein the 2.8-5.3 wt. % of rare earth elements comprise 2.1-2.9 wt. % Ce and 0.7-2.4 wt. % La. In some embodiments, Alloy 3 from Table 1 includes 4.5-6.5 wt. % of rare earth elements, wherein the 4.5-6.5 wt. % of rare earth elements comprise 2.9-4.0 wt. % Ce and 1.6-2.5 wt. % La. In some embodiments, Alloy 4 from Table 1 includes 5.0-6.0 wt. % of rare earth elements, wherein the 5.0-6.0 wt. % of rare earth elements comprise 3.2-3.7 wt. % Ce and 1.8-2.3 wt. % La. In some embodiments, Alloy 5 from Table 1 includes 6.5-8.4 wt. % of rare earth elements, wherein the 6.5-8.4 wt. % of rare earth elements comprise 4.1-5.2 wt. % Ce and 2.4-3.2 wt. % La. In some embodiments, Alloy 6 from Table 1 includes 7.0-7.9 wt. % of rare earth elements, wherein the 7.0-7.9 wt. % of rare earth elements comprise 4.4- 4.9 wt. % Ce and 2.6-3.0 wt. % La.

[0013] In some embodiments, the Class A metals of Alloys 1-6 of Table 1 include at least iron. In some embodiments, the rare earth elements of Alloys 1-6 include at least one of cerium, lanthanum and mixtures thereof. In some embodiments of Alloys 1-6 of Table 1, the Class A metal is iron, and the rare earth elements are cerium, lanthanum and mixtures thereof.

[0014] In some embodiments, Alloys 1-6 of Table 1 may include not greater than 0.20 wt. % Si. In some embodiments, Alloys 1-6 of Table 1 may include not greater than 0.15 wt. % Si. In some embodiments, Alloys 1-6 of Table 1 may include not greater than 0.10 wt. % Si. In some embodiments, Alloys 1-6 of Table 1 may include not greater than 0.60 wt. % O. In some embodiments, Alloys 1-6 of Table 1 may include not greater than 0.25 wt. % O. In some embodiments, Alloys 1-6 of Table 1 may include the following elements as impurities: Cu, Mg, and Zn (e.g., not greater than 0.05 wt. % of each of any of the previously stated elements). In some embodiments, Alloys 1-6 of Table 1 may include not greater than 0.05 wt. % each of other impurities (impurities other than the Cu, Mg, and Zn), with the total combined amount of the other impurities being not greater than 0.15 wt. %.

[0015] The total amount of Class A metal(s) plus rare earth elements in the new aluminum alloys may facilitate realization of improved properties. The amount of Class A metal(s) plus rare earth elements relates to the amount of Al-A-RE-X intermetallics in the alloy. In one embodiment, the total amount of Class A metal(s) and rare earth elements within an aluminum alloy is at least 5 wt. % (i.e., (wt. % Class A metal(s)) plus (wt. % rare earth elements) > 5 wt. %). In another embodiment, the total amount of Class A metal(s) and rare earth elements within an aluminum alloy is at least 6 wt. %. In yet another embodiment, the total amount of Class A metal(s) and rare earth elements within an aluminum alloy is at least 7 wt. %. In another embodiment, the total amount of Class A metal(s) and rare earth elements within an aluminum alloy is at least 8 wt. %. In yet another embodiment, the total amount of Class A metal(s) and rare earth elements within an aluminum alloy is at least 9 wt. %. In another embodiment, the total amount of Class A metal(s) and rare earth elements within an aluminum alloy is at least 10 wt. %. In one embodiment, an aluminum alloy includes at least 2 wt. % rare earth elements and at least 6 wt. % Class A metal(s). In another embodiment, an aluminum alloy includes at least 2.5 wt. % rare earth elements and at least 6 wt. % Class A metal(s). In another embodiment, a new alloy includes at least 3 wt. % rare earth elements and at least 6 wt. % Class A metal(s). In another embodiment, a new alloy includes at least 3 wt. % rare earth elements and at least 7 wt. % Class A metal(s). In one embodiment, a new alloy includes at least 3 wt. % rare earth elements and at least 3 wt. % Class A metal(s). In another embodiment, a new alloy includes at least 4 wt. % rare earth elements and at least 4 wt. % Class A metal(s). In yet another embodiment, a new alloy includes at least 5 wt. % rare earth elements and at least 4 wt. % Class A metal(s). In another embodiment, a new alloy includes at least 5 wt. % rare earth elements and at least 5 wt. % Class A metal(s). In yet another embodiment, a new alloy includes at least 6 wt. % rare earth elements and at least 5 wt. % Class A metal(s).

[0016] In one embodiment, an aluminum alloy includes at least two rare earth elements. In another embodiment, an aluminum alloy includes at least both cerium and lanthanum. In one embodiment, an aluminum alloy includes misch metal. In one embodiment, the misch metal is a cerium-rich misch metal. In another embodiment, the misch metal is a lanthanum-rich misch metal. In one embodiment, the rare earth elements consist essentially of cerium and lanthanum. In one embodiment, the ratio of Ce:La is from about 0.15: 1 to 6: 1. In one embodiment, the ratio of Ce:La is at least 0.33: 1. In another embodiment, the ratio of Ce:La is at least 0.67: 1. In yet another embodiment, the ratio of Ce:La is at least 1 : 1. In another embodiment, the ratio of Ce:La is at least 1.25: 1. In yet another embodiment, the ratio of Ce:La is at least 1.5: 1. In one embodiment, the ratio of Ce:La is not greater than 5: 1. In another embodiment, the ratio of Ce:La is not greater than 4: 1. In yet another embodiment, the ratio of Ce:La is not greater than 3.5: 1. In another embodiment, the ratio of Ce:La is not greater than 3: 1.

[0017] In any of the above embodiments, the alloy may include the Class A metal(s) and the rare earth element(s) such that RE (wt. %) > -3.1 l(wt. % Class A metal) + 13.4. In any of the above embodiments, the alloy may include the Class A metal(s) and the rare earth element(s) such that RE (wt. %) < -3. l l(wt. % Fe) + 38. In any of the above embodiments, the alloy may include the Class A metal(s) and the rare earth element(s) such that RE (wt. %) > - 3. l l(wt. % Fe) + 18. In any of the above embodiments, the alloy may include the Class A metal(s) and the rare earth element(s) such that RE (wt. %) < -3.1 l(wt. % Fe) + 34.75.

c. X-B, X-C, X-O, X-N compounds and Other Ceramic Materials

[0018] In one approach, a new aluminum alloy product contains low amounts of X-B, X-C, X-N, and/or X-0 compounds. Such compounds may, in some instances, degrade alloy properties. “X-B compounds” are compounds of boron and at least one of the Class X metals. TiB₂ is an X-B compound. “X-C compounds” are compounds of carbon and at least one of the Class X metals. TiC is an X-C compound. “X-N compounds” are compounds of nitrogen and at least one of the Class X metals. TiN is an X-N compound. “X-0 compounds” are compounds of oxygen and at least one of the Class X metals. Ti0₂ is an X- O compound. In one embodiment, an additively manufactured product contains not greater than 1.0 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In another embodiment, an additively manufactured product contains not greater than 0.75 wt. %, in total, of X-B, X- C, X-N, and/or X-0 compounds. In yet another embodiment, an additively manufactured product contains not greater than 0.50 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In another embodiment, an additively manufactured product contains not greater than 0.35 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In yet another embodiment, an additively manufactured product contains not greater than 0.25 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In another embodiment, an additively manufactured product contains not greater than 0.15 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In yet another embodiment, an additively manufactured product contains not greater than 0.10 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In another embodiment, an additively manufactured product contains not greater than 0.08 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In yet another embodiment, an additively manufactured product contains not greater than 0.05 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In another embodiment, an additively manufactured product contains not greater than 0.03 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In yet another embodiment, an additively manufactured product contains not greater than 0.01 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In another embodiment, an additively manufactured product contains not greater than 0.007 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In yet another embodiment, an additively manufactured product contains not greater than 0.005 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In another embodiment, an additively manufactured product contains not greater than 0.003 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds. In yet another embodiment, an additively manufactured product contains not greater than 0.001 wt. %, in total, of X-B, X-C, X-N, and/or X-0 compounds.

[0019] In some embodiments, the new aluminum alloy products contain low amounts of other ceramic materials. As used herein,“other ceramic materials” means ceramic materials other than the X-B, X-C, X-N, and X-0 compounds described above. Examples of other ceramics include, but are not limited to, oxide materials, boride materials, carbide materials, nitride materials, silicon materials, carbon materials, and/or combinations thereof. Some additional examples of other ceramic materials include metal oxides, metal borides, metal carbides, metal nitrides and/or combinations thereof. Additionally, some non-limiting examples of other ceramic materials include: SiC, AI2O3, BC, BN, S13N4, AI4C3, A1N, their suitable equivalents, and/or combinations thereof. In one embodiment, an additively manufactured product contains not greater than 1.0 wt. %, in total, of other ceramic materials. In another embodiment, an additively manufactured product contains not greater than 0.75 wt. %, in total, of other ceramic materials. In yet another embodiment, an additively manufactured product contains not greater than 0.50 wt. %, in total, of other ceramic materials. In another embodiment, an additively manufactured product contains not greater than 0.35 wt. %, in total, of other ceramic materials. In yet another embodiment, an additively manufactured product contains not greater than 0.25 wt. %, in total, of other ceramic materials. In another embodiment, an additively manufactured product contains not greater than 0.15 wt. %, in total, of other ceramic materials. In yet another embodiment, an additively manufactured product contains not greater than 0.10 wt. %, in total, of other ceramic materials. In another embodiment, an additively manufactured product contains not greater than 0.08 wt. %, in total, of other ceramic materials. In yet another embodiment, an additively manufactured product contains not greater than 0.05 wt. %, in total, of other ceramic materials. In another embodiment, an additively manufactured product contains not greater than 0.03 wt. %, in total, of other ceramic materials. In yet another embodiment, an additively manufactured product contains not greater than 0.01 wt. %, in total, of other ceramic materials. In another embodiment, an additively manufactured product contains not greater than 0.007 wt. %, in total, of other ceramic materials. In yet another embodiment, an additively manufactured product contains not greater than 0.005 wt. %, in total, of other ceramic materials. In another embodiment, an additively manufactured product contains not greater than 0.003 wt. %, in total, of other ceramic materials. In yet another embodiment, an additively manufactured product contains not greater than 0.001 wt. %, in total, of other ceramic materials.

d. Incidental Elements

[0020] As noted above, the balance of the new aluminum alloys may be aluminum, any optional incidental elements and impurities. As used herein,“incidental elements” includes casting aids and/or grain structure control materials (e.g., grain refiners) that may be used in the aluminum alloy.

[0021] Some incidental elements may be added to the alloy to reduce or restrict (and is some instances eliminate) cracking in the additively manufactured part due to, for example, folds (e.g., oxide folds), pits and patches (e.g., oxide patches). These types of incidental elements are generally referred to herein as deoxidizers. Examples of some deoxidizers include Ca, Sr, P and Be. When calcium (Ca) is included in the alloy, it is generally present in an amount of up to 0.3 wt. %, or up to 0.2 wt. %, or up to 0.1 wt. %. In some embodiments, Ca is included in the alloy in an amount of 0.001-0.1 wt. % or 0.001- 0.2 wt. % or 0.001-0.3 wt. %, such as 0.001-0.25 wt. % (or 10 to 2500 ppm). Strontium (Sr) may be included in the alloy as a substitute for Ca (in whole or in part), and thus may be included in the alloy in the same or similar amounts as Ca. Phosphorus (P) may be included in the alloy as a substitute for Ca or Sr (in whole or in part), and thus may be included in the alloy in the same or similar amounts as Ca or Sr. Traditionally, beryllium (Be) additions have helped to reduce the tendency of cracking in aluminum alloys, though for environmental, health and safety reasons, some embodiments of the alloy are substantially Be-free. When Be is included in the alloy, it is generally present in an amount of up to 0.05 wt. % (e.g., from 10 ppm to 500 ppm of Be). ii. Microstructure

[0022] As noted above, the new aluminum alloy products generally comprise Al-A-RE-X intermetallics. Other intermetallics may also be included in the new aluminum alloy products. In one approach, a new aluminum alloy product comprises Al-X intermetallics. “Al-X intermetallics” are compounds of aluminum and at least one Class X metal. Non limiting examples of Al-X intermetallics include Al₃X, Al₇X, AhoX, and Al_l2X compounds, among others. Multiple Class X metals may be included in a single Al-X intermetallic compound. As used herein,“Al₃X intermetallics” are compounds having 3 aluminum atoms per one Class X atom. Some Al₃X intermetallics useful in accordance with the present disclosure include AI3T1, AhZr, AhHf, AhSc, AhNb, and AhTa. Other non-limiting examples of Al-X intermetallics include AI12M0, Al_l2W, Al₇Cr, and AhoV, among others.

[0023] In one embodiment, the amount of the Al-A-RE-X intermetallics of the new aluminum alloy product exceeds the amount of the Al-X intermetallics. In one embodiment, the volume ratio of Al-A-RE-X intermetallics to Al-X intermetallics is at least 2: 1. In another embodiment, the volume ratio of Al-A-RE-X intermetallics to Al-X intermetallics is at least 3: 1. In yet another embodiment, the volume ratio of Al-A-RE-X intermetallics to Al- X intermetallics is at least 4: 1. In another embodiment, the volume ratio of Al-A-RE-X intermetallics to Al-X intermetallics is at least 5: 1. In yet another embodiment, the volume ratio of Al-A-RE-X intermetallics to Al-X intermetallics is at least 6: 1. In another embodiment, the volume ratio of Al-A-RE-X intermetallics to Al-X intermetallics is at least 7: 1. In yet another embodiment, the volume ratio of Al-A-RE-X intermetallics to Al-X intermetallics is at least 8: 1. In another embodiment, the volume ratio of Al-A-RE-X intermetallics to Al-X intermetallics is at least 9: 1. In yet another embodiment, the volume ratio of Al-A-RE-X intermetallics to Al-X intermetallics is at least 10: 1.

[0024] The Al-A-RE-X intermetallics may facilitate, for instance, production of new aluminum alloy product having an equiaxed grain structure. In one embodiment, a new aluminum alloy product comprises grains and wherein at least 50 vol. % of the grains are equiaxed grains. In another embodiment, a new aluminum alloy product comprises at least 60 vol.% equiaxed grains. In yet another embodiment, a new aluminum alloy product comprises at least 70 vol.% equiaxed grains. In another embodiment, a new aluminum alloy product comprises at least 80 vol.% equiaxed grains. In yet another embodiment, a new aluminum alloy product comprises at least 90 vol.% equiaxed grains. In another embodiment, a new aluminum alloy product comprises at least 95 vol.% equiaxed grains. In yet another embodiment, a new aluminum alloy product comprises at least 97 vol.% equiaxed grains. In another embodiment, a new aluminum alloy product comprises at least 99 vol.% equiaxed grains. In yet another embodiment, a new aluminum alloy product consists essentially of equiaxed grains.

[0025] The Al-A-RE-X intermetallics may facilitate, for instance, production of new aluminum alloy product having an appropriate average equiaxed grain size. In one embodiment, an average grain size of the equiaxed grains is from 0.5 - 50 micrometers (e.g., in the as-built condition). In one embodiment, the average size of the equiaxed grains of the additively manufactured aluminum alloy product in the as-built condition is generally not greater than 50 microns. In one embodiment, the average size of the equiaxed grains of the additively manufactured aluminum alloy product in the as-built condition is not greater than 40 microns. In another embodiment, the average size of the equiaxed grains of the additively manufactured aluminum alloy product in the as-built condition is not greater than 30 microns. In yet another embodiment, the average size of the equiaxed grains of the additively manufactured aluminum alloy product in the as-built condition is not greater than 20 microns. In another embodiment, the average size of the equiaxed grains of the additively manufactured aluminum alloy product in the as-built condition is not greater than 10 microns. In yet another embodiment, the average size of the equiaxed grains of the additively manufactured aluminum alloy product in the as-built condition is not greater than 5 microns. In another embodiment, the average size of the equiaxed grains of the additively manufactured aluminum alloy product in the as-built condition is not greater than 4 microns. In yet another embodiment, the average size of the equiaxed grains of the additively manufactured aluminum alloy product in the as-built condition is not greater than 3 microns. In another embodiment, the average size of the equiaxed grains of the additively manufactured aluminum alloy product in the as-built condition is not greater than 2 microns, or less.

[0026] In one approach, the Al-A-RE-X intermetallics comprise one or both of: (a) primary Al-A-RE-X intermetallics and (b) nanoscale Al-A-RE-X intermetallics. “Primary Al-A-RE- X intermetallics” are primary phase Al-A-RE-X intermetallics, i.e., the Al-A-RE-X intermetallics are the first solid to form during cooling of a liquid comprising the Class A metal(s), the rare earth element(s), and the Class X metal(s). Primary Al-A-RE-X intermetallics are generally greater than 350 nanometers in size. Nanoscale Al-A-RE-X intermetallics are Al-A-RE-X intermetallics less than 350 nanometers in size. [0027] In one embodiment, an average size of the nanoscale Al-A-RE-X intermetallics is not greater than 300 nm. In another embodiment, an average size of the nanoscale Al-A-RE-X intermetallics is not greater than 250 nm. In yet another embodiment, an average size of the nanoscale Al-A-RE-X intermetallics is not greater than 200 nm. In another embodiment, an average size of the nanoscale Al-A-RE-X intermetallics is not greater than 150 nm. In yet another embodiment, an average size of the nanoscale Al-A-RE-X intermetallics is not greater than 100 nm. In another embodiment, an average size of the nanoscale Al-A-RE-X intermetallics is not greater than 75 nm.

[0028] In one embodiment, a new aluminum alloy product comprises a homogenous (generally uniform) distribution of the nanoscale Al-A-RE-X intermetallics. In one embodiment, the Al-A-RE-X intermetallics consist essentially of the primary Al-A-RE-X intermetallics and the nanoscale Al-A-RE-X intermetallics.

[0029] In one embodiment, an average size of the primary Al-A-RE-X intermetallics is not greater than 10 micrometers. In another embodiment, an average size of the primary Al-A- RE-X intermetallics is not greater than 8 micrometers. In yet another embodiment, an average size of the primary Al-A-RE-X intermetallics is not greater than 6 micrometers. In another embodiment, an average size of the primary Al-A-RE-X intermetallics is not greater than 4 micrometers. In yet another embodiment, an average size of the primary Al-A-RE-X intermetallics is not greater than 2 micrometers. In another embodiment, an average size of the primary Al-A-RE-X intermetallics is not greater than 1 micrometers. In yet another embodiment, an average size of the primary Al-A-RE-X intermetallics is not greater than 0.75 micrometers.

[0030] The new aluminum alloy products may comprise an appropriate amount of the Al-A- RE-X intermetallics (combined primary and nanoscale). In one embodiment, an aluminum alloy product comprises at least 10 vol. % of the Al-A-RE-X intermetallics. In another embodiment, an aluminum alloy product comprises at least 15 vol. % of the Al-A-RE-X intermetallics. In yet another embodiment, an aluminum alloy product comprises at least 20 vol. % of the Al-A-RE-X intermetallics. In another embodiment, an aluminum alloy product comprises at least 25 vol. % of the Al-A-RE-X intermetallics. In one embodiment, a new aluminum alloy product comprises not greater than 40 vol. % of the Al-A-RE-X intermetallics.

[0031] In some embodiments, the new aluminum alloys described herein may realize a low volume fraction of primary Al-A-RE-X spheroidal particles. In one embodiment, an aluminum alloy product comprises not greater than 20 vol. % of primary Al-A-RE-X spheroidal particles. In another embodiment, an aluminum alloy product comprises not greater than 15 vol. % of primary Al-A-RE-X spheroidal particles. In another embodiment, an aluminum alloy product comprises not greater than 10 vol. % of primary Al-A-RE-X spheroidal particles. In yet another embodiment, an aluminum alloy product comprises not greater than 8 vol. % of primary Al-A-RE-X spheroidal particles. In another embodiment, an aluminum alloy product comprises not greater than 5 vol. % of primary Al-A-RE-X spheroidal particles. In yet another embodiment, an aluminum alloy product comprises not greater than 3 vol. % of primary Al-A-RE-X spheroidal particles.

[0032] As noted above, the new aluminum alloy products may comprise a homogeneous (generally uniform) distribution of the nanoscale particles. In one embodiment, a new aluminum alloy product also comprises one or more of lamellar, cellular, brick and wavy microstructures. In another embodiment, a new aluminum alloy product comprises a homogeneous distribution of the nanoscale particles, but is absent of lamellar, cellular, brick and wavy microstructures (e.g., due to thermal or thermomechanical processing).

iii. Methods of Production

[0033] The new aluminum alloy products may be made via any suitable production methodology. In one embodiment, the new aluminum alloys are in a cast form such as in the form of an ingot or billet (e.g., for using in making atomized powders). In one embodiment, the processing route involves rapid solidification, such as high-pressure die casting and some continuous castings techniques. In one embodiment, the new aluminum alloys are additively manufactured, as described below. In one embodiment, the new aluminum alloys are in the form of powders or wires (e.g., for use in an additive manufacturing process). In one embodiment, the new aluminum alloys are in the form of sheets (e.g., foils) for use in additive manufacturing processes such as sheet lamination, per ASTM F2792-l2a.

[0034] In one embodiment, a method includes (a) preparing a molten mixture, wherein the molten mixture comprises (i) 1 - 15 wt. % of the Class A metals, (ii) 1 - 20 wt. % of the rare earth elements, (iii) 0.1 - 5 wt. % of the Class X metals, and (b) cooling the molten mixture into a solid product, wherein the cooling comprises (i) forming primary Al-A-RE-X intermetallics and (ii) nucleating FCC aluminum grains on at least some of the primary Al-A- RE-X intermetallics. In one embodiment, the balance of the aluminum alloy is aluminum, any optional incidental elements and impurities. In one embodiment, a method also includes forming nanoscale Al-A-RE-X intermetallics (e.g., via solid-state formation). The solid product may comprise a homogenous distribution of the nanoscale Al-A-RE-X intermetallics. Standard examination by SEM or other microscropy may be used to show a product’s distribution of materials (e.g., homogenous or heterogeneous).

[0035] The solid product may be any product, including an ingot or billet, a shape casting, a wrought product, or an additively manufactured product. In one embodiment, the solid product is an ingot or billet. In one embodiment, a method includes preparing a powder or wire from the solid product. In one embodiment, a method includes using the prepared powder to make an additively manufactured product. Due to, for instance, the Al-A-RE-X intermetallics, additively manufactured aluminum alloy products may realize an improved combination of properties over conventional additively manufactured aluminum alloy products. In one embodiment, a new additively manufactured aluminum alloy product realizes an improved combination of at least two of strength, fracture toughness, corrosion resistance, fatigue resistance, and fatigue crack growth resistance as compared to an additively manufactured aluminum alloy product without Al-A-RE-X intermetallics and/or as compared to an additively manufactured aluminum alloy product having high amounts of X- B compounds, X-C compounds, X-N compounds, X-0 compounds, and/or other ceramic materials.

[0036] In one embodiment, an additive manufacturing process includes depositing successive layers of one or more powders and then selectively melting and/or sintering the powders to create, layer-by-layer, an additively manufactured aluminum alloy body (product). In one embodiment, an additive manufacturing processes uses one or more of Selective Laser Sintering (SLS), Selective Laser Melting (SLM), and Electron Beam Melting (EBM), among others. In one embodiment, an additive manufacturing process uses an EOSINT M 280 Direct Metal Laser Sintering (DMLS) additive manufacturing system, or comparable system, available from EOS GmbH (Robert-Stirling-Ring 1, 82152 Krailling/Munich, Germany). In one embodiment, additive manufacturing process uses a LENS additive manufacturing system, or comparable system, available from OPTOMEC, 3911 Singer N.E., Albuquerque, NM 87109.

[0037] As one example, a feedstock, such as a powder or wire, comprising (or consisting essentially of, or consisting of) the Al, the Class A metal(s), the rare earth element(s), the Class X metal(s) and any optional incidental elements (e.g., X-B, X-C, X-N, and/or X-0 compounds, and/or other ceramic materials) and impurities, and within the scope of the compositions described above, may be used in an additive manufacturing apparatus to produce an additively manufactured aluminum alloy body. In some embodiments, the additively manufactured aluminum alloy body is a crack-free preform. The feedstock may be selectively heated above the liquidus temperature of the material, thereby forming a molten pool having the Al, the Class A metal(s), the rare earth element(s), the Class X metal(s) and any optional incidental elements and impurities, followed by rapid solidification of the molten pool thereby forming an additively manufactured aluminum alloy product, generally with 10-40% vol. % of Al-A-RE-X interm etallics therein.

[0038] As noted above, additive manufacturing may be used to create, layer-by-layer, the aluminum alloy product. In one embodiment, a metal powder bed is used to create a tailored aluminum alloy product. As used herein a“metal powder bed” means a bed comprising a metal powder. During additive manufacturing, particles of the same or different compositions may melt (e.g., rapidly melt) and then solidify (e.g., in the absence of homogenous mixing). Thus, products having a homogenous or non-homogeneous microstructure may be produced. One embodiment of a method of making an additively manufactured aluminum alloy body may include (a) dispersing a powder comprising the Al, the Class A metal(s), the rare earth element(s), the Class X metal(s) and any optional incidental elements and impurities, (b) selectively heating a portion of the powder (e.g., via a laser) to a temperature above the liquidus temperature of the particular body to be formed, (c) forming a molten pool having the Al, the Class A metal(s), the rare earth element(s), the Class X metal(s) and any optional incidental elements and impurities, and (d) cooling the molten pool at a cooling rate of at least l000°C per second. In one embodiment, the cooling rate is at least l0,000°C per second. In another embodiment, the cooling rate is at least l00,000°C per second. In another embodiment, the cooling rate is at least l,000,000°C per second. Steps (a)-(d) may be repeated as necessary until the aluminum alloy body is completed, i.e., until the final additively manufactured aluminum alloy body is formed / completed. The final additively manufactured aluminum alloy body may be of a complex geometry, or may be of a simple geometry (e.g., in the form of a sheet or plate), and may comprise 10-40% vol. % of Al-A-RE-X intermetallics therein. After or during production, an additively manufactured aluminum alloy product may be deformed (e.g., by one or more of rolling, extruding, forging, stretching, compressing).

[0039] The powders used to additively manufacture an aluminum alloy body may be produced by atomizing a material (e.g., an ingot or melt) of the new alloy aluminum alloys into powders of the appropriate dimensions relative to the additive manufacturing process to be used. As used herein,“powder” means a material comprising a plurality of particles. Powders may be used in a powder bed to produce a tailored alloy product via additive manufacturing. In one embodiment, the same general powder is used throughout the additive manufacturing process to produce an aluminum alloy product. For instance, the final tailored aluminum alloy product may comprise a single region / matrix produced by using generally the same metal powder during the additive manufacturing process. The final tailored aluminum alloy product may alternatively comprise at least two separately produced distinct regions. In one embodiment, different metal powder bed types may be used to produce the aluminum alloy product. For instance, a first metal powder bed may comprise a first metal powder and a second metal powder bed may comprise a second metal powder, different than the first metal powder. The first metal powder bed may be used to produce a first layer or portion of the alloy product, and the second metal powder bed may be used to produce a second layer or portion of the alloy product. As used herein, a“particle” means a minute fragment of matter having a size suitable for use in the powder of the powder bed (e.g., a size of from 5 microns to 100 microns). Particles may be produced, for example, via atomization. Powders or particles may be produced by, for instance, plasma atomization, gas atomization, or impingement of a molten aluminum alloy (e.g., solidification of an impinging molten metal droplet on a cold substrate).

[0040] The additively manufactured aluminum alloy body may be subject to any appropriate working steps. If employed, the working steps may be conducted on an intermediate form of the additively manufactured body and/or may be conducted on a final form of the additively manufactured body. In one embodiment, an additively manufactured body consists essentially of the Al, the Class A metal(s), the rare earth element(s), the Class X metal(s) and any optional incidental elements and impurities, such as any of the material compositions described above.

[0041] In another embodiment, an aluminum alloy body is a preform for subsequent working. A preform may be an additively manufactured product. In one embodiment, a preform is of a near net shape product that is close to the final desired shape of the final product, but the preform is designed to allow for subsequent working to achieve the final product shape. Thus, the preform may worked such as by forging, rolling, extrusion, or hipping to produce an intermediate product or a final product, which intermediate or final product may be subject to any further appropriate working or thermal steps (e.g., stress relief), as described above, to achieve the final product. In one embodiment, the working comprises hot isostatic pressing (hipping) to compress the part. In one embodiment, an aluminum alloy preform may be compressed and porosity may be reduced. In one embodiment, the hipping temperature is maintained below the incipient melting point of the aluminum alloy preform. In one embodiment, the preform may be a near net shape product. [0042] In one approach, electron beam (EB) or plasma arc techniques are utilized to produce at least a portion of the additively manufactured aluminum alloy body. Electron beam techniques may facilitate production of larger parts than readily produced via laser additive manufacturing techniques. In one embodiment, a method comprises feeding a small diameter wire (e.g., < 5 mm in diameter) of the new aluminum alloys described herein to the wire feeder portion of an electron beam gun. The wire may be of the compositions, described above. The electron beam (EB) heats the wire above the liquidus point of the body to be formed, followed by rapid solidification (e.g., at least l00°C per second) of the molten pool to form the deposited material. The wire could be fabricated by a conventional ingot process or by a powder consolidation process. These steps may be repeated as necessary until the final aluminum alloy body is produced. Plasma arc wire feed may similarly be used with the aluminum alloys disclosed herein. In one embodiment, not illustrated, an electron beam (EB) or plasma arc additive manufacturing apparatus may employ multiple different wires with corresponding multiple different radiation sources, each of the wires and sources being fed and activated, as appropriate to provide the aluminum alloy product.

[0043] In another approach, a method may comprise (a) selectively spraying one or more metal powders of the new aluminum alloys described herein towards a building substrate, (b) heating, via a radiation source, the metal powders, and optionally the building substrate, above the liquidus temperature of the product to be formed, thereby forming a molten pool, (c) cooling the molten pool, thereby forming a solid portion of the product, wherein the cooling comprises cooling at a cooling rate of at least l00°C per second. In one embodiment, the cooling rate is at least l000°C per second. In another embodiment, the cooling rate is at least l0,000°C per second. The cooling step (c) may be accomplished by moving the radiation source away from the molten pool and/or by moving the building substrate having the molten pool away from the radiation source. Steps (a)-(c) may be repeated as necessary until the product is completed. The spraying step (a) may be accomplished via one or more nozzles, and the composition of the metal powders can be varied, as appropriate, to provide a tailored final aluminum alloy product. The composition of the metal powder being heated at any one time can be varied in real-time by using different powders in different nozzles and/or by varying the powder composition(s) provided to any one nozzle in real-time. The work piece can be any suitable substrate. In one embodiment, the building substrate is, itself, a metal product (e.g., an alloy product, such as any of the aluminum alloy products described herein.) iv. Anodizing

[0044] Methods of producing anodized aluminum alloy bodies from the above-described aluminum alloys are also disclosed, one embodiment of which is illustrated in FIG. 4. In the illustrated embodiment, the method (500) includes the steps of preparing an aluminum alloy body of the new aluminum alloys described herein for oxide layer formation (520), electrochemically forming an oxide layer in the aluminum alloy body (540), optionally dying the aluminum alloy body (560), and one or more optional post-dye processes (580).

[0045] The preparing step (520) may include any number of steps useful in preparing the aluminum alloy body for formation of the electrochemically formed oxide layer. For example, and as described in further detail below, the preparing step (520) may include producing the aluminum alloy body (e.g., via additive manufacturing), cleaning the body, and/or chemically brightening the body.

[0046] The step of electrochemically forming the oxide layer in the body (540) may be accomplished via any suitable apparatus or processes, such as anodizing. Anodizing may be performed using a variety of different process parameters including current density, bath composition, time, and temperature. In one approach, the anodizing is Type II anodizing and in accordance with MIL-A-8625. In another embodiment, the anodizing is Type III anodizing, per MIL-A-8625. Additional anodizing information is provided below.

[0047] The optional step of dying the body (560) may include immersing the body in one or more dye baths, with optional rinsing between and/or after the dying steps.

[0048] The optional post-dye processes (580) may include sealing the dyed aluminum alloy body and/or polishing the dyed aluminum alloy body, as described in further detail below.

[0049] One particular embodiment of producing an aluminum alloy body of the new aluminum alloys described herein is illustrated in FIG. 5. In the illustrated embodiment, the method (500) includes the steps of preparing the aluminum alloy body for anodizing (520), anodizing the aluminum alloy body (540), dying the aluminum alloy body (560), and one or more optional post-dye processes (580).

[0050] In the illustrated embodiment, the step of preparing the aluminum alloy body for anodizing (520) includes the steps of producing the aluminum alloy body (522), cleaning the aluminum alloy body (524), and brightening (e.g., electrochemically polishing, or chemical polishing) the aluminum alloy body (526).

[0051] With respect to the step of producing the aluminum alloy body (522), the aluminum alloy body may be produced via any suitable aluminum alloy production processes, as described above. [0052] With respect to the cleaning step (524), this cleaning may be accomplished by any known conventional processes and/or cleaning agents, such as via the use of acidic and/or basic cleansers or detergents that produce a water break free surface (water wettable). In one embodiment, the cleaning agent is a non-alkaline cleaner, such as A-31K manufactured by Henkel International, Germany. For example, the cleaning step (524) may include cleaning the intended viewing surface of the aluminum alloy body with a non-etching alkaline cleaner for about two minutes to remove lubricants or other residues that may have formed during the bright-rolling step. After the cleaning step (524), the body may be rinsed or double rinsed with a suitable rinsing agent, such as water. In one embodiment, the suitable rinsing agent is de-ionized water. Other suitable rinsing agents may be utilized.

[0053] With respect to the brightening step (526), the brightening may include electrochemical or chemical polishing. The electrochemical polishing may be accomplished via any suitable processes, such as via use of an electrolyte in the presence of current. Some methods of electrochemical polishing are disclosed in U.S. Patent No. 4,740,280, which is incorporated herein by reference in its entirety. The chemical brightening (polishing) may be accomplished via any suitable processes, such as via a mixture of phosphoric acid and nitric acid in the presence of water, or via the methods described in U.S. Patent No. 6,440,290 to Vega et al., which is incorporated herein by reference in its entirety. For example, the brightening step (526) may include chemical etching by immersing in a phosphoric acid- based solution (e.g., DAB80) for a period of about two minutes to about four minutes, followed by a warm bath double rinse similar to that discussed above, immersion in a 50 % nitric acid solution at room temperature for about thirty seconds, and another double rinse step.

[0054] In one embodiment, the brightening step (526) may include mechanical polishing by grinding, roughing, oiling or greasing, buffing or mopping, and coloring, among other suitable mechanical processes.

[0055] As used herein,“polishing” and the like means to smooth or brighten a surface to increase the reflective quality and luster, such as mechanical polishing by grinding, polishing and buffing, or to improve the surface conditions of the aluminum product for decorative or functional purposes. For example, mechanical polishing may be utilized to increase gloss. In one embodiment, an aluminum alloy body of the new aluminum alloys described herein may be first bright rolled followed by mechanical polishing to produce high image clarity at the intended viewing surface of the aluminum alloy body. [0056] With respect to the anodizing step (540), the anodizing may be accomplished via any suitable electrolyte and current density. In one embodiment, the anodizing step includes utilizing an electrolyte having 12 to 25 wt. % H₂S0₄, a current density of 8 to 36 amps per square foot (ASF), and with an electrolyte temperature of between 60 °F to 80 °F.

[0057] As used herein,“anodizing” and the like means those processes that produce an oxide zone of a selected thickness in a body via application of current to the body while the body is in the presence of an electrolyte.

[0058] In one embodiment, the electrolyte comprises at least 12 wt. % sulfuric acid, such as at least 14 wt. % sulfuric acid. In one embodiment, the electrolyte comprises not greater than 25 wt. % sulfuric acid. In other embodiments, the electrolyte comprises not greater than 22 wt. % sulfuric acid, or not greater than 20 wt. % sulfuric acid.

[0059] In some embodiments, the electrolyte includes at least one of phosphoric acid, boric/sulfuric acid, chromic acid, and oxalic acid, among other suitable acid mediums.

[0060] In one embodiment, the current density during anodizing is at least about 8 ASF. In other embodiments, the current density is at least about 10 ASF or at least about 12 ASF. In one embodiment, the current density is not greater than about 24 ASF. In other embodiments, the current density is not greater than about 20 ASF, or not greater than about 18 ASF.

[0061] In one embodiment, the temperature of the electrolyte during anodizing is at least about 40 °F. In other embodiments, the temperature of the electrolyte during anodizing is at least about 50 °F, such as at least about 60 °F. In one embodiment, the temperature of the electrolyte during anodizing is not greater than about 100 °F. In other embodiments, the temperature of the electrolyte during anodizing is not greater than 90 °F, such as not greater than 80 °F.

[0062] In one embodiment, the anodizing step (540) produces an electrochemically formed oxide zone in the body, the electrochemically formed oxide zone having a thickness of from 0.05 to 1.5 mil.

[0063] In one embodiment, after the anodizing step (540), the aluminum alloy body may be subjected to a double rinse step, followed by immersion in a 50 % nitric acid solution at room temperature for about 60 seconds, and another double rinse step.

[0064] With respect to the dying step (560), the dying may include an optional first dying step (562), and optionally at least one additional dying step (566). In one embodiment, the optional dying step (560) includes at least two dying steps. Additional dying sequences may be used. [0065] As used herein,“dye” and the like means a color material used for coloring a body. Dyes may be any suitable color, such as red, orange, yellow, green, blue, indigo, violet, black, white, and mixtures thereof. Dyes are usually water-based, and placed in contact with bodies via immersion techniques. However, dyes may be applied to the body in other ways, such as, for example, via spraying, spraying-immersion, and the like. Irrespective of the manner of application of the dye, the dye should contact the surface of the oxide zone of the aluminum alloy body for a sufficient amount of time to enable the pores of the oxide zone to retain the dye (e.g., via absorption).

[0066] In one embodiment, the dye is an aqueous-based dye. Examples of suitable dyes include those produced by Clariant, Pigments and Additives Division, 500 Washington Street, Coventry, Rhode Island, 02816 United States (http://www.pa.clariant.com/).

[0067] With respect to the optional post-dye processes (580), such processes may include one or more of sealing the dyed aluminum alloy body (582) and polishing the aluminum alloy body (584).

[0068] With respect to the sealing step (582), the sealing may be useful to close the oxide pores or prevent the color of the dyes from bleeding or leaking out of the oxide zone. The sealing step can be accomplished via any known conventional processes, such as by hot sealing with de-ionized water or steam or by cold sealing with impregnation of a sealant in a room-temperature bath. In one approach, at least some, or in some instances all or nearly all, of the pores of the oxide zone may be sealed with a sealing agent, such as, for instance, an aqueous salt solution at elevated temperature (e.g., boiling salt water) or nickel acetate. After the sealing step the body may again be double rinsed with a rinsing agent.

[0069] With respect to the polishing step (584), the polishing may be accomplished via any suitable means so as to increase, for example, the gloss of the aluminum alloy body.

v. Applications

[0070] The new aluminum alloy products / bodies of the new aluminum alloys described herein may be suitable in aerospace and/or automotive applications. In one embodiment, a new aluminum alloy is used in a ground transportation application. Non-limiting examples of aerospace applications may include heat exchangers and turbines. In one embodiment, a new aluminum alloy product / body is in the form of a compressor component (e.g., turbocharger impeller wheels). Non-limiting examples of automotive applications may include interior or exterior trim/appliques, pistons, valves, and/or turbochargers. Other examples include any components close to a hot area of the vehicle, such as engine components and/or exhaust components, such as the manifold. A new aluminum alloy product may be 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. A method may include operating such an aerospace or automotive vehicle. In any of the above embodiments, the final aluminum alloy product may be a compressor wheel for a turbocharger. In any of the above embodiments, the final aluminum alloy product may be one of a heat exchanger and a piston.

[0071] Aside from the applications described above, the new aluminum alloy bodies of the present disclosure may also be utilized in a variety of consumer products, such as any consumer electronic products, including laptops, cell phones, cameras, mobile music players, handheld devices, computers, televisions, microwave, cookware, washer/dryer, refrigerator, sporting goods, or any other consumer electronic product requiring durability and selective visual appearance. In one embodiment, the visual appearance of the consumer electronic product meets consumer acceptance standards.

[0072] In some embodiments, the new aluminum alloy bodies of the present disclosure may be utilized in a variety of products including non-consumer products including the likes of medical devices, transportation systems and security systems, to name a few. In other embodiments, the new aluminum alloy bodies may be incorporated in goods including the likes of car panels, media players, bottles and cans, office supplies, packages and containers, among others.

[0073] As noted above, the new aluminum alloys may be used in a variety of product applications. In this regard, at least a portion of a product (e.g., an additively manufactured product) may comprise any of the new aluminum alloy compositions described above. For instance, at least a portion of an aluminum alloy product may comprise one of the new aluminum alloy compositions, and at least one other portion may be comprised of a different material (e.g., a different aluminum alloy). Furthermore, the new aluminum alloy compositions may be present in a product comprising a compositional gradient (i.e., a graded product). At least a portion of a graded product may comprise any of the new aluminum alloy compositions described above.

17. Additional Definitions

[0074] As used herein,“ additive manufacturing" means“a process of joining materials to make objects from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing methodologies”, as defined in ASTM F2792-l2a entitled “Standard Terminology for Additively Manufacturing Technologies”. Non-limiting examples of additive manufacturing processes useful in producing crack-free aluminum alloy products include, for instance, DMLS (direct metal laser sintering), SLM (selective laser melting), SLS (selective laser sintering), and EBM (electron beam melting), among others. Any suitable feedstocks may be used, including one or more powders, one or more wires, one or more sheets, and combinations thereof. In some embodiments the additive manufacturing feedstock is comprised of one or more powders. Shavings are types of particles. In some embodiments, the additive manufacturing feedstock is comprised of one or more wires. A ribbon is a type of wire. In some embodiments, the additive manufacturing feedstock is comprised of one or more sheets. Foil is a type of sheet.

[0075] As used herein,“grain” takes on the meaning defined in ASTM El 12 §3.2.2, i.e.,“the area within the confines of the original (primary) boundary observed on the two-dimensional plane of-polish or that volume enclosed by the original (primary) boundary in the three- dimensional object”.

[0076] As used herein, the“grain size” is calculated by the following equation:

v/ = square root (—)

• wherein A i is the area of the individual grain as measured using commercial software Edax OIM version 8.0 or equivalent; and

• wherein vi is the calculated individual grain size assuming the grain is a circle. Grain size is determined based on a two-dimensional plane that includes the build direction of the additively manufactured product.

[0077] As used herein, the“ area weighted average grain size” is calculated by the following equation

v-bar

• wherein A i is the area of each individual grain as measured using commercial software Edax OIM version 8.0 or equivalent;

• wherein vi is the calculated individual grain size assuming the grain is a circle; and

• wherein v-bar is the area weighted average grain size.

[0078] As used herein,“ e uiaxed grains” means grains having an average aspect ratio of less than 4: 1 as measured in the XY, YZ, and XZ planes. The“aspect ratio” is determined using commercial software Edax OIM version 8.0 or equivalent. The commercial software fits an ellipse to the perimeter points of the grain. As used herein,“aspect ratio” is the inverse of: the length of the minor axis of the ellipse divided by the length of the major axis of the ellipse as determined using commercial software. In one embodiment, an additively manufactured aluminum alloy part comprises equiaxed grains having an average aspect ratio of not greater than 4: 1. In one embodiment, an additively manufactured aluminum alloy part comprises equiaxed grains having an average aspect ratio of not greater than 3: 1. In one described embodiment, an additively manufactured aluminum alloy part comprises equiaxed grains having an average aspect ratio of not greater than 2: 1. In one embodiment, an additively manufactured aluminum alloy part comprises equiaxed grains having an average aspect ratio of not greater than 1.5: 1. In one embodiment, an additively manufactured aluminum alloy part comprises equiaxed grains having an average aspect ratio of not greater than 1.1 : 1. The amount (volume percent) of equiaxed grains in the additively manufactured product in the as- built condition may be determined by EBSD (electron backscatter diffraction) analysis of a suitable number of SEM micrographs of the additively manufactured product in the as-built condition. Generally at least 5 micrographs should be analyzed.

[0079] In some embodiments, the additively manufactured product is a crack-free product. In some embodiments,“ crack-free” means that the product is sufficiently free of cracks such that it can be used for its intended, end-use purpose. The determination of whether a product is“crack-free” may be made by any suitable method, such as, by visual inspection, dye penetrant inspection, and/or by non-destructive test methods. In some embodiments, the non destructive test method is an ultrasonic inspection. In some embodiments, the non-destructive test method is a computed topography scan (“CT scan”) inspection (e.g., by measuring density differences within the product). In one embodiment, an aluminum alloy product is determined to be crack-free by visual inspection. In another embodiment, an aluminum alloy product is determined to be crack-free by dye penetrant inspection. In yet another embodiment, an aluminum alloy product is determined to be crack-free by CT scan inspection, as evaluated in accordance with ASTM E1441. In another embodiment, an aluminum alloy product is determined to be crack-free during an additive manufacturing process, wherein in situ monitoring of the additively manufactured build is employed.

[0080] As used herein, the“ as-built condition’’ means the condition of the additively manufactured aluminum alloy product after production and absent of any subsequent mechanical, thermal or thermomechanical treatments.

[0081] Throughout the specification and claims, the following terms take the meanings explicitly associated herein, unless the context clearly dictates otherwise. The phrases“in one embodiment” and“in some embodiments” as used herein do not necessarily refer to the same embodiment s), though they may. Furthermore, the phrases“in another embodiment” and“in some other embodiments” as used herein do not necessarily refer to a different embodiment, although they may. Thus, as described below, various embodiments of the invention may be readily combined, without departing from the scope or spirit of the invention.

[0082] In addition, as used herein, the term“or” is an inclusive“or” operator, and is equivalent to the term“and/or,” unless the context clearly dictates otherwise. The term “based on” is not exclusive and allows for being based on additional factors not described, unless the context clearly dictates otherwise. In addition, throughout the specification, the meaning of“a,”“an,” and“the” include plural references, unless the context clearly dictates otherwise. The meaning of“in” includes“in” and“on”, unless the context clearly dictates otherwise.

[0083] While a number of embodiments of the present invention have been described, it is understood that these embodiments are illustrative only, and not restrictive, and that many modifications may become apparent to those of ordinary skill in the art. Further still, unless the context clearly requires otherwise, the various steps may be carried out in any desired order, and any applicable steps may be added and/or eliminated.

BRIEF DESCRIPTION OF THE DRAWINGS

[0084] FIG. la is an SEM (scanning electron microscope) image of Alloy A of Example 1.

[0085] FIG. lb is an EBSD (electron backscatter diffraction) image of Alloy A of Example 1.

[0086] FIG. 2a is an SEM image of Alloy B of Example 1.

[0087] FIG. 2b is an EBSD image of Alloy B of Example 1.

[0088] FIG. 3a is an EBSD image of Alloy C of Example 1.

[0089] FIG. 3b- 1 is an SEM image of Alloy C of Example 1.

[0090] FIG. 3b-2 is a close-up SEM image of FIG. 3b- 1.

[0091] FIG. 4 is a flow chart illustrating one embodiment of a method for producing an anodized, optionally dyed, and optionally post-dye processed aluminum alloy body of the new aluminum alloys described herein.

[0092] FIG. 5 is a flow chart illustrating one embodiment of a method for producing an anodized, optionally dyed, and optionally post-dye processed aluminum alloy body of the new aluminum alloys described herein.

DETAILED DESCRIPTION

[0093] Example 1 [0094] An Al-Fe-RE alloy (Alloy A) having a composition consistent with that disclosed in commonly owned International Patent Application No. PCT/US 18/27622, filed April 13, 2018, and entitled “ALUMINUM ALLOYS HAVING IRON AND RARE EARTH ELEMENTS” (incorporated herein by reference in its entirety) was produced by additive manufacturing and without any grain refiner materials. The produced aluminum alloy product comprises a lamellar structure (FIG. la) and columnar grains (FIG. lb). The as-built aluminum alloy product, using traditional additive manufacturing machine operations, exhibited at least some columnar grains. Without being bound by a particular mechanism or theory, additive products having a certain content of columnar grains with the columnar grains having a particular orientation may not be optimized and/or suited for a specified end use application (e.g. without additional processing).

[0095] Another Al-Fe-RE alloy (Alloy B) was also produced using additive manufacturing but using about 3 wt. % of TiB₂ grain refiner materials (Alloy B). As noted above, TiB₂ is a type of X-B compound. The produced aluminum alloy product comprises primary particles and a microcellular structure within equiaxed grains, as shown in FIGS. 2a-2b, respectively. While the cracking was reduced, the properties of the aluminum alloy product were also reduced.

[0096] Another Al-Fe-RE alloy (Alloy C) was also produced using additive manufacturing but using about 1 wt. % of Ti as a grain refiner material and without any purposeful additions of any TiB₂ materials. The alloy was laser remelted to simulate additive manufacturing conditions. No cracking is seen in the laser remelted product indicating that the alloy may be resistant to hot cracking. The produced aluminum alloy product comprises larger equiaxed grains (20-40 micrometers) as compared to Alloy B, as shown in FIG. 3a. The larger grains may be advantageous for fracture toughness and fatigue crack growth as crack propagation becomes more tortuous as grain size is increased.

[0097] Unexpectedly, a fine nanoscale dispersion of intermetallic particles is observed (FIGS. 3b-l and 3b-2). It is believed that the intermetallic particles are Al-Fe-RE-Ti intermetallic particles, which is a non-limiting example of a type of Al-A-RE-X intermetallic particles that may be formed / produced based on the aluminum alloy compositions described herein. Further, this type of morphology, i.e., a nanometer scaled dispersion of intermetallic particles embedded in an aluminum matrix, is desired because it combines attributes of high strength (e.g., dispersion induced resistance to strain) and high toughness (e.g., a ductile aluminum matrix). [0098] Without being bound by any particular mechanism or theory, aluminum alloy products having a fine nanoscale dispersion of intermetallic particles are believed to provide uniquely tailored products, improved properties in an additive feedstock, improved properties in an additive manufacturing product, and/or combinations thereof. As additional features, the unique balance may reduce, prevent, and/or eliminate cracking, the presence of columnar grains in an unsuitable orientation in the part (e.g. based on part specifications), and/or post- build or in situ processing during the additive manufacturing process.

[0099] 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.

Claims

CLAIMS What is claimed is:

1. An aluminum alloy product comprising:

(a) 1 - 15 wt. % of Class A metals, wherein the Class A metals comprise at least one of manganese (Mn), iron (Fe), cobalt (Co), and nickel (Ni);

(b) 1 - 20 wt. % of rare earth elements; and

(c) 0.1 - 5 wt. % of Class X metals, wherein the Class X metals comprise at least one of titanium (Ti), zirconium (Zr), hafnium (Hf), scandium (Sc), vanadium (V), molybdenum (Mo), niobium (Nb), tantalum (Ta), tungsten (W) and chromium (Cr);

wherein the aluminum alloy product comprises Al-A-RE-X intermetallics.

2. The aluminum alloy product of claim 1, wherein the aluminum alloy product is substantially free of X-B compounds, X-C compounds, X-N compounds, X-0 compounds, and other ceramic materials.

3. The aluminum alloy product of any of the preceding claims, wherein the aluminum alloy product comprises Al-X intermetallics, and wherein the amount of the Al-A-RE-X intermetallics exceeds the amount of the Al-X intermetallics.

4. The aluminum alloy product of any of the preceding claims, wherein the volume ratio of Al-A-RE-X intermetallics to Al-X intermetallics is at least 2: 1.

5. The aluminum alloy product of any of the preceding claims, wherein the volume ratio of Al-A-RE-X intermetallics to Al-X intermetallics is at least 10: 1.

6. The aluminum alloy product of any of the preceding claims, wherein the aluminum alloy product comprises grains and wherein at least 50 vol. % of the grains are equiaxed grains, or at least 60 vol.%, or at least 70 vol.%, or at least 80 vol.%, or at least 90 vol.%, or at least 95 vol.%, or at least 97 vol.%, or at least 99 vol.%, or wherein the grains consist essentially of equiaxed grains.

7. The aluminum alloy product of any of the preceding claims, wherein an average grain size of the equiaxed grains is from 0.5 - 50 micrometers.

8. The aluminum alloy product of any of the preceding claims, wherein the Al-A-RE- X intermetallics comprise at least one of (a) primary Al-A-RE-X intermetallics and (b) nanoscale Al-A-RE-X intermetallics, wherein the nanoscale Al-A-RE-X intermetallics are Al-A-RE-X intermetallics less than 350 nanometers in size.

9. The aluminum alloy product of claim 8, wherein the aluminum alloy product comprises a homogenous distribution of the nanoscale Al-A-RE-X intermetallics.

10. The aluminum alloy product of claim 8, wherein the Al-A-RE-X intermetallics consist essentially of the primary Al-A-RE-X intermetallics and the nanoscale Al-A-RE-X intermetallics.

11. The aluminum alloy of any of the preceding claims, wherein the aluminum alloy product comprises at least 10 vol. % of the Al-A-RE-X intermetallics, or at least 15%, or at least 20%, or at least 25%.

12. The aluminum alloy of any of the preceding claims, wherein the aluminum alloy product comprises not greater than 40 vol. % of the Al-A-RE-X intermetallics.

13. The aluminum alloy product of any of the preceding claims, wherein the aluminum alloy product is absent of lamellar, cellular, brick and wavy microstructures.

14. The aluminum alloy product of any of the preceding claims, wherein the aluminum alloy product comprises at least 0.5 wt. % of the Class X metals, or at least 0.75 wt. % of the Class X metals, or at least 1.0 wt. % of the Class X metals, or at least 1.5 wt. % of the Class X metals, or at least 2.0 wt. % of the Class X metals, or at least 2.5 wt. % of the Class X metals, or at least 3.0 wt. % of the Class X metals, or at least 3.5 wt. % of the Class X metals, or at least 4.0 wt. % of the Class X metals, or at least 4.5 wt. % of the Class X metals.

15. The aluminum alloy product of any of the preceding claims, wherein the aluminum alloy product comprises an amount of the Class X metals that is sufficient to realize at least 10 vol. % of Al-A-RE-X intermetallics and wherein the amount of the Class X metals exceeds its solubility limit in the aluminum alloy product.

16. The aluminum alloy product of any of the preceding claims, wherein the balance of the aluminum alloy product is aluminum, optional incidental elements, and impurities.

17. The aluminum alloy product of any of the preceding claims, wherein the aluminum alloy product is crack-free.

18. An additive manufacturing feedstock made from the aluminum alloy products of any of the preceding claims, wherein the additive manufacturing feedstock is one of a wire, a powder, sheet and combinations thereof.

19. The aluminum alloy product of claim 17, wherein the aluminum alloy product is an automotive component or an aerospace component.

20. The aluminum alloy product of claim 19, wherein the automotive component or the aerospace component is an engine component.

21. The aluminum alloy product of claim 19, wherein the automotive component or the aerospace component is a compressor component.

22. The aluminum alloy product of claim 19, wherein the automotive component or the aerospace component is one of a heat exchanger or a piston.

23. A method comprising:

(a) preparing a molten mixture, wherein the molten mixture comprises:

(i) 1 - 15 wt. % of Class A metals, wherein the Class A metals comprise at least one of manganese (Mn), iron (Fe), cobalt (Co) and nickel (Ni);

(ii) 1 - 20 wt. % of rare earth elements; and

(iii) 0.1 - 5 wt. % of Class X metals, wherein the Class X metals comprise at least one of titanium (Ti), zirconium (Zr), hafnium (Hf), scandium (Sc), vanadium (V), molybdenum (Mo), niobium (Nb), tantalum (Ta), tungsten (W) and chromium (Cr);

(b) cooling the molten mixture into a solid product, wherein the cooling comprises:

(i) forming primary Al-A-RE-X intermetallics;

(ii) nucleating FCC aluminum grains on at least some of the primary Al-A-RE-X intermetallics.

24. The method of claim 24, wherein the balance of the molten mixture is aluminum, any optional incidental elements, and impurities.

25. The method of any of claims 23-24, comprising:

during or after the cooling step (b), forming nanoscale Al-A-RE-X intermetallics.

26. The method of claim 25, wherein the forming the nanoscale Al-A-RE-X intermetallics step comprises solid-state formation.

27. The method of any of claims 25-26, wherein the solid product comprises a homogenous distribution of the nanoscale Al-A-RE-X intermetallics.

28. The method of claim 23, wherein the solid product is an ingot or billet.

29. The method of claim 23, comprising:

preparing an additive manufacturing feedstock from the solid product.

30. The method of claim 29, comprising:

using the additive manufacturing feedstock in an additive manufacturing apparatus to make an additively manufactured product.

31. The method of claim 23, wherein the molten mixture is a melt pool, wherein the molten pool is produced by an energy source of an additive manufacturing apparatus, and wherein the solid product is an additively manufactured product.