6XXX aluminum alloys with improved recoverability

Abstract

The invention relates to an AlMgSi alloy which is particularly advantageous for recovery. The subject of the invention is an aluminum-based alloy comprising, in wt%: Mg: 0.2-1.5; 0.3 to 2.0 parts of Si; 0.25 to 1.0 percent of Fe; 0.01 to 0.15 percent of Ti; at least one element selected from the group consisting of Co, Ba, Ni, La, Ce, Ta, Mo, W, Nb, Re, Pr, Nd, Pm, Sm, Y, Ru and Os, the content thereof being 0.003 to 0.20, preferably 0.005 to 0.15, if selected; zr: less than or equal to 0.15; mn: less than or equal to 1.5; v: 0.20 or less; zn: < = 1.0; cr: less than or equal to 0.25; cu: less than or equal to 1.5; and the balance of aluminum and inevitable impurities. The small addition of certain elements can alter the size and distribution of intermetallic particles, and thus tolerate an increase in impurity (in particular iron) content. The invention further relates to a heat treatment forged product containing the alloy and a manufacturing method of the heat treatment forged product. The invention is particularly suitable for automotive manufacturing, building construction, aeronautical manufacturing or industrial construction.

Description

Technical Field

[0001] The present invention relates to a 6XXX series aluminum alloy, which can increase the recovery rate of this type of alloy in forged products, especially in the automotive field. Background Art

[0002] Recycled aluminum has economic and environmental advantages. The energy required to produce recycled aluminum is up to 95% less than that of primary aluminum, and it can reduce CO2 emissions. To improve the environmental impact of aluminum production, the aluminum industry seeks to maximize the level of recycled materials in products. However, an increase in the level of recycled materials usually leads to an increase in impurity content, especially iron content, resulting in an increase in the volume fraction and / or size of intermetallic particles, which may be disadvantageous for, for example, process (such as homogenization) duration, forming-related properties (such as elongation and formability), and surface properties (anodic oxidation response). This problem is illustrated in, for example, the article Texture control by thermomechanical processing of AA6xxx Al-Mg-Si sheet alloys for automotive applications—a review in the journal Materials Science and Engineering A336 (2002) 249-262.

[0003] To avoid such adverse effects, purification of the metal can be considered.

[0004] Patent FR2902800 describes a method for manufacturing remelted ingots from scrap, which can particularly remove iron and silicon from scrap of 2XXX series or 7XXX series alloys without removing alloying elements such as zinc, copper, and magnesium.

[0005] However, these additional purification steps may ultimately be difficult to implement and costly.

[0006] Patent application WO2015 / 151907A1 also mentions the problem of impurity content in recycled alloys.

[0007] Patent application US20080175747 describes an alloy in which impurities hardly affect the properties.

[0008] Patent Application JP2007169740 A describes an alloy containing, by weight %, Si: 0.5 - 1.5%, Mg: 0.2 - 2.0%, Fe: 1.5% or less, Mn: 1.0% or less, Cr: 0.5% or less, Zr: 0.5% or less, V: 0.3% or less, Ti: 0.2% or less, Zn = 1.5% or less, Cu: or less and containing not less than 0.015% and not more than 0.5% of Bi, Sn, Ga, Co, Ni, Ca, Mo, Be, Pb and W, with the balance being aluminum and impurities.

[0009] Patent Application JP2016037632 describes an aluminum alloy sheet metal containing Mg: 0.2 wt% to 2.0 wt%, Si: 0.3 wt% to 2.0 wt%, Fe: 0.01 wt% to 0.5 wt%, one or both of Ni and Co, in total 0.002 wt% to 0.3 wt%, with the balance being Al and inevitable impurities.

[0010] Patent EP2072628 describes an extruded or forged product made of an AlMgSi type aluminum alloy, which contains, by weight %, Si 0.5 to 0.95, Mg 0.6 to 0.95, Mn 0.1 to 0.3, V 0.05 to 0.25, Ni 0.05 to 0.25, Cu at most 0.3, one or two elements optionally selected from the following: (Cr 0.05 to 0.2, Zr 0.05 to 0.2), Zn < 0.2, Fe < 0.5, Ti < 0.1, inevitable impurities, with the balance being aluminum.

[0011] Patent Application CN112342443 relates to an explosion-proof barrier material which contains, by weight %, 0.4% to 0.8% of Si, 0.4% to 1.0% of Fe, 0.2% to 0.4% of Cu, 0.3% to 0.7% of Mn, 0.1% to 0.25% of Zn, 0.1% to 0.2% of Ti, 0.8% to 1.2% of Mg, 0.03% to 0.4% of Cr, 0.05% to 0.15% of Zr, 0.1% to 0.3% of Sc, 0.1% to 0.3% of Ni, with the balance being Al.

[0012] Patent Application US2020 / 095664 relates to high-strength aluminum alloys and methods for manufacturing and processing these alloys.

[0013] Patent application CN106756320 relates to a flow-through rack made of aluminum alloy, which contains, by weight percentage: 1.5% to 2.0% of Mg, 1% to 1.4% of Si, 0.2% to 0.5% of Fe, 0.05% to 0.09% of Zn, 0.1% to 0.3% of Cu, 0.2% to 0.4% of Mn, 0.01% to 0.04% of C, 0.2% to 0.4% of B, 0.02% to 0.04% of W, 0.05% to 0.07% of Zr, 0.1% to 0.4% of Cr, 0.05% to 0.09% of Ti, 20% to 35% of aluminum scrap, 0.5% to 1.5% of rare earth elements, and the balance is aluminum.

[0014] Therefore, the problem to be solved by the present invention is to provide an alloy that can tolerate increased impurity content, especially iron, so that no additional purification is required and the homogenization time is also limited. Summary of the Invention

[0015] The first object of the present invention is an aluminum-based alloy, which contains, by weight percentage:

[0016] - Mg: 0.2 - 1.5;

[0017] - Si: 0.3 - 2.0;

[0018] - Fe: 0.30 - 1.0;

[0019] - Ti: 0.01 - 0.15;

[0020] - At least one element selected from Co, Ba, Ni, La, Ce, Ta, Mo, W, Nb, Re, Pr, Nd, Pm, Sm, Y, Ru, Os. If this element is selected, its content is 0.003 to 0.20, preferably 0.005 to 0.15,

[0021] - Zr: ≤0.15;

[0022] - Mn: ≤1.5;

[0023] - V: ≤0.20;

[0024] - Zn: ≤1.0;

[0025] - Cr: ≤0.25;

[0026] - Cu: ≤1.5;

[0027] - The balance is aluminum and unavoidable impurities, and the content of impurities is at most 0.05% by weight.

[0028] Another object of the present invention is a heat-treated forging product containing the alloy of the present invention.

[0029] Another object of the present invention is a method for manufacturing the heat-treated forged product of the present invention, comprising the following steps:

[0030] - Supplying pure aluminum or aluminum alloy in the form of a primary metal ingot derived from electrolysis and / or pre-consumer manufacturing waste and / or post-consumer waste, said waste optionally having been separately melted and possibly solidified, and alloying elements in a suitable form;

[0031] - Forming a charge with the supplied aluminum, melting the charge, and adding alloying elements to obtain a liquid alloyed metal bath of the present invention;

[0032] - Casting the liquid metal bath, preferably by direct-chill vertical semi-continuous casting, to obtain a billet suitable for hot working, typically a rolled plate, a forging billet or a square billet;

[0033] - Homogenizing the billet at a temperature of at least 500 °C;

[0034] - Hot working and optionally cold working the billet by rolling, extrusion and / or forging to obtain a forged product;

[0035] - Subjecting the forged product thus obtained to solution heat treatment and quenching at a temperature of at least 500 °C;

[0036] - Aging and / or tempering the solution heat-treated and quenched forged product thus obtained at room temperature to obtain a heat-treated forged product.

[0037] Another object of the present invention is the use of the product of the present invention in automotive manufacturing, construction, aviation manufacturing or industrial construction. Description of the Drawings

[0038] Figure 1 Shows the relationship between the size of the intermetallic particles and the spacing between the intermetallic particles tested in Example 1.

[0039] Figure 2 Shows the relationship between the size of the intermetallic particles and the spacing between the intermetallic particles tested in Example 2.

[0040] Figure 3 Shows the relationship between the size of the intermetallic particles and the spacing between the intermetallic particles tested in Example 3.

[0041] Figure 4 Shows the relationship between the size of the intermetallic particles and the spacing between the intermetallic particles tested in Example 4.

[0042] Figure 5 Shows the BSE contrast electron microscope image of the intermetallic particles in the tests conducted.

[0043] Figure 6 shows the Figure 5 image after the first step of processing by image analysis.

[0044] Figure 7 shows the Figure 5 image after the second step of processing by image analysis, which includes at least two consecutive steps of closing the object, enabling the calculation of the average size and average distance of the intermetallic particles.

[0045] Figure 8 is an optical microscope image of the test of adding La in Example 5.

[0046] Figure 9 is an optical microscope image of the test without adding La in Example 5. Detailed Description

[0047] Unless otherwise specified, all statements regarding the chemical composition of the alloy are expressed as weight percentages based on the total weight of the alloy. The expression 1.4Cu or 1.4(Cu) means that the copper content expressed in weight % is multiplied by 1.4. The naming of the alloy complies with the rules of The Aluminum Association, which are well known to those skilled in the art. Unless otherwise specified, the metallurgical temper definitions of standard EN515–2017 apply.

[0048] The inventors have noticed that, surprisingly, adding a small amount of some elements to an AlMgSi alloy (also known as the 6XXX series alloy) can change the size and distribution of the intermetallic particles and thus tolerate an increase in the content of impurities (especially iron).

[0049] Intermetallic particles refer to compounds containing several metallic elements or metalloid elements formed during the solidification process after the formation of crystalline aluminum in the face-centered cubic form, such as Al3Fe, Mg2Si, AlFeSi, AlFeMnSi, etc.

[0050] The alloys of the present invention are AlMgSi alloys. Therefore, they contain 0.2% to 1.5% of Mg and 0.3% to 2.0% of Si.

[0051] In one embodiment, the Mg content is at least 0.4%, or at least 0.5%, or at least 0.6%, or at least 0.7%, or at least 0.8%, or at least 0.9%, or at least 1.0%, or at least 1.1%, or at least 1.2%, or at least 1.3%, and / or at most 1.4%, or at most 1.3%, or at most 1.2%, or at most 1.1%, or at most 1.0%, or at most 0.9%, or at most 0.8%, or at most 0.7%, or at most 0.6%, or at most 0.5%.

[0052] In one embodiment, the Si content is at least 0.4%, or at least 0.5%, or at least 0.6%, or at least 0.7%, or at least 0.8%, or at least 0.9%, or at least 1.0%, or at least 1.1%, or at least 1.2%, or at least 1.3%, or at least 1.4%, or at least 1.5%, or at least 1.6%, or at least 1.7%, or at least 1.8%, and / or at most 1.9%, or at most 1.8%, or at most 1.7%, or at most 1.6%, or at most 1.5%, or at most 1.4%, or at most 1.3%, or at most 1.2%, or at most 1.1%, or at most 1.0%, or at most 0.9%, or at most 0.8%, or at most 0.7%, or at most 0.6%, or at most 0.5%.

[0053] Copper is an element that can be added to the AlMgSi alloy, in particular to improve the mechanical properties. The Cu content is at most 1.5 wt%. In one embodiment, the Cu content is from 0.05 wt% to 1 wt%. In one embodiment, the Cu content is at least 0.10%, or at least 0.15%, or at least 0.20%, or at least 0.25%, or at least 0.30%, or at least 0.35%, or at least 0.40%, or at least 0.45%, or at least 0.50%, or at least 0.55%, or at least 0.60%, or at least 0.65%, or at least 0.70%, or at least 0.75%, or at least 0.80%, or at least 0.85%, or at least 0.90%, or at least 0.95%, or at least 1.00%, or at least 1.05%, or at least 1.10%, or at least 1.15%, or at least 1.20%, or at least 1.25%, or at least 1.30%, or at least 1.35%, or at least 1.40%, and / or at most 1.45%, or at most 1.40%, or at most 1.35%, or at most 1.30%, or at most 1.25%, or at most 1.20%, or at most 1.15%, or at most 1.10%, or at most 1.05%, or at most 1.00%, or at most 0.95%, or at most 0.90%, or at most 0.85%, or at most 0.80%, or at most 0.75%, or at most 0.70%, or at most 0.65%, or at most 0.60%, or at most 0.55%, or at most 0.50%, or at most 0.45%, or at most 0.40%, or at most 0.35%, or at most 0.30%, or at most 0.25%, or at most 0.20%, or at most 0.15%.

[0054] For the main elements Mg, Si and optionally Cu, the contents in alloys AA6005, AA6005A, AA6105, AA6205, AA6305, AA6008, AA6009, AA6010, AA6011, AA6111, AA6012, AA6013, AA6014, AA6015, AA6016, AA6116, AA6018, AA6019, AA6020, AA6021, AA6022, AA6023, AA6024, AA6025, AA6026, AA6027, AA6028, AA6031, AA6032, AA6033, AA6040, AA6040, AA6041, AA6042, AA6043, AA6050, AA6151, AA6351, AA6053, AA6055, AA6056, AA6156, AA6060, AA6061, AA6261, AA6361, AA6162, AA6262, AA6063, AA6064, AA6065, AA6066, AA6068, AA6069, AA6070, AA6081, AA6082, AA6182, AA6086, AA6091, AA6092, AA6099 are embodiments of the present invention.

[0055] The Ti content is from 0.01 wt% to 0.15 wt%. In one embodiment, the Ti content is at least 0.02%, or at least 0.03%, or at least 0.04%, or at least 0.05%, or at least 0.06%, or at least 0.07%, or at least 0.08%, or at least 0.09%, or at least 0.10%, or at least 0.11%, or at least 0.12%, or at least 0.13%, and / or at most 0.14%, or at most 0.13%, or at most 0.12%, or at most 0.11%, or at most 0.10%, or at most 0.09%, or at most 0.08%, or at most 0.07%, or at most 0.06%, or at most 0.05%, or at most 0.04%, or at most 0.03%. The addition of titanium in the form of metallic titanium and / or TiB2 and / or TiC is necessary to obtain the desired effect, because this addition can achieve a grain size that allows the change of the intermetallic particle size and distribution. In a preferred embodiment, metallic titanium and TiC are added. Advantageously, the addition of TiC is carried out by adding 0.5 kg to 2 kg per ton of metal, preferably 0.8 kg to 1.2 kg per ton of metal of Al3%Ti0.15%C and / or Al1%Ti0.2%C.

[0056] The Fe content is from 0.30% to 1.0% by weight. In one embodiment, the Fe content is at least 0.32% or at least 0.35%, or at least 0.40%, or at least 0.45%, or at least 0.50%, or at least 0.55%, or at least 0.60%, or at least 0.65%, or at least 0.70%, or at least 0.75%, or at least 0.80%, or at least 0.85%, or at least 0.90%, and / or at most 0.95%, or at most 0.90%, or at most 0.85%, or at most 0.80%, or at most 0.75%, or at most 0.70%, or at most 0.65%, or at most 0.60%, or at most 0.55%, or at most 0.50%, or at most 0.45%, or at most 0.40%, or at most 0.35%. In one embodiment of the present invention, the Fe content is from 0.35% to 0.85% by weight, preferably from 0.4% to 0.7% by weight.

[0057] According to the present invention, at least one element selected from Co, Ba, Ni, La, Ce, Ta, Mo, W, Nb, Re, Pr, Nd, Pm, Sm, Y, Ru, Os is added, and if this element is selected, the content of this element is 0.003 wt% to 0.20 wt%. The content of elements not selected from Co, Ba, Ni, La, Ce, Ta, Mo, W, Nb, Re, Pr, Nd, Pm, Sm, Y, Ru, Os is less than 0.003 wt%. Advantageously, at least one element selected from Co, Ba, Ni, La, Ce, Ta is added, and if this element is selected, the content of this element is 0.003 wt% to 0.20 wt%. In one embodiment, at least one element is selected from Co, Ba, Ni, La, Ce, Mo, W, and if this element is selected, the content of this element is 0.003 wt% to 0.20 wt%.In one embodiment, the content of elements selected from Co, Ba, Ni, La, Ce, Ta, Mo, W, Nb, Re, Pr, Nd, Pm, Sm, Y, Ru, Os and preferably selected from Co, Ba, Ni, La, Ce, Ta is at least 0.004%, or at least 0.009%, or at least 0.014%, or at least 0.019%, or at least 0.024%, or at least 0.029%, or at least 0.034%, or at least 0.039%, or at least 0.044%, or at least 0.049%, or at least 0.054%, or at least 0.059%, or at least 0.064%, or at least 0.069%, or at least 0.074%, or at least 0.079%, or at least 0.084%, or at least 0.089%, or at least 0.094%, or at least 0.099%, or at least 0.104%, or at least 0.109%, or at least 0.114%, or at least 0.119%, or at least 0.124%, or at least 0.129%, or at least 0.134%, or at least 0.139%, or at least 0.144%, or at least 0.149%, or at least 0.154%, or at least 0.159%, or at least 0.164%, or at least 0.169%, or at least 0.174%, or at least 0.179%, or at least 0.184%, or at least 0.189%, or at least 0.194% and / or at most 0.195%, or at most 0.190%, or at most 0.185%, or at most 0.180%, or at most 0.175%, or at most 0.170%, or at most 0.165%, or at most 0.160%, or at most 0.155%, or at most 0.150%, or at most 0.145%, or at most 0.140%, or at most 0.135%, or at most 0.130%, or at most 0.125%, or at most 0.120%, or at most 0.115%, or at most 0.110%, or at most 0.105%, or at most 0.100%, or at most 0.095%, or at most 0.090%, or at most 0.085%, or at most 0.080%, or at most 0.075%, or at most 0.070%, or at most 0.065%, or at most 0.060%, or at most 0.055%, or at most 0.050%, or at most 0.045%, or at most 0.040%, or at most 0.035%, or at most 0.030%, or at most 0.025%, or at most 0.020%, or at most 0.015%, or at most 0.010%.

[0058] In one embodiment, at least one element selected from Co, Ba, Ni, La, Ce, Ta, Mo, W, Nb, Re, Pr, Nd, Pm, Sm, Y, Ru, Os is added, and if this element is selected, the content of this element is from 0.009 wt% to 0.090 wt%.

[0059] In an advantageous embodiment, at least one element is selected from Co, Ba, Ni, La, Ce, Ta, and if this element is selected, the content of this element is from 0.005 wt% to 0.15 wt%.

[0060] The Zr content is at most 0.15 wt%. In an advantageous embodiment, the Zr content is from 0.003 wt% to 0.15 wt%. In one embodiment, the Zr content is at least 0.004%, or at least 0.009%, or at least 0.014%, or at least 0.019%, or at least 0.024%, or at least 0.029%, or at least 0.034%, or at least 0.039%, or at least 0.044%, or at least 0.049%, or at least 0.054%, or at least 0.059%, or at least 0.064%, or at least 0.069%, or at least 0.074%, or at least 0.079%, or at least 0.084%, or at least 0.089%, or at least 0.094%, or at least 0.099%, or at least 0.104%, or at least 0.109%, or at least 0.114%, or at least 0.119%, or at least 0.124%, or at least 0.129%, or at least 0.134%, or at least 0.139% and / or at most 0.145%, or at most 0.140%, or at most 0.135%, or at most 0.130%, or at most 0.125%, or at most 0.120%, or at most 0.115%, or at most 0.110%, or at most 0.105%, or at most 0.100%, or at most 0.095%, or at most 0.090%, or at most 0.085%, or at most 0.080%, or at most 0.075%, or at most 0.070%, or at most 0.065%, or at most 0.060%, or at most 0.055%, or at most 0.050%, or at most 0.045%, or at most 0.040%, or at most 0.035%, or at most 0.030%, or at most 0.025%, or at most 0.020%, or at most 0.015%, or at most 0.010%.

[0061] The Mn content is at most 1.5% by weight. In an advantageous embodiment of the present invention, the Mn content is from 0.03% to 1.0% by weight. In one embodiment, the Mn content is at least 0.05%, or at least 0.10%, or at least 0.15%, or at least 0.20%, or at least 0.25%, or at least 0.30%, or at least 0.35%, or at least 0.40%, or at least 0.45%, or at least 0.50%, or at least 0.55%, or at least 0.60%, or at least 0.65%, or at least 0.70%, or at least 0.75%, or at least 0.80%, or at least 0.85%, or at least 0.90%, or at least 0.95%, or at least 1.00%, or at least 1.05%, or at least 1.10%, or at least 1.15%, or at least 1.20%, or at least 1.25%, or at least 1.30%, or at least 1.35%, or at least 1.40% and / or at most 1.45%, or at most 1.40%, or at most 1.35%, or at most 1.30%, or at most 1.25%, or at most 1.20%, or at most 1.15%, or at most 1.10%, or at most 1.05%, or at most 1.00%, or at most 0.95%, or at most 0.90%, or at most 0.85%, or at most 0.80%, or at most 0.75%, or at most 0.70%, or at most 0.65%, or at most 0.60%, or at most 0.55%, or at most 0.50%, or at most 0.45%, or at most 0.40%, or at most 0.35%, or at most 0.30%, or at most 0.25%, or at most 0.20%, or at most 0.15%, or at most 0.10%.

[0062] The V content is at most 0.20% by weight. In one embodiment of the present invention, the V content is from 0.05% to 0.20% by weight. In one embodiment, the V content is at least 0.06%, or at least 0.07%, or at least 0.08%, or at least 0.09%, or at least 0.10%, or at least 0.11%, or at least 0.12%, or at least 0.13%, or at least 0.14%, or at least 0.15%, or at least 0.16%, or at least 0.17%, or at least 0.18% and / or at most 0.19%, or at most 0.18%, or at most 0.17%, or at most 0.16%, or at most 0.15%, or at most 0.14%, or at most 0.13%, or at most 0.12%, or at most 0.11%, or at most 0.10%, or at most 0.09%, or at most 0.08%, or at most 0.07%.

[0063] The Zn content is at most 1.0 wt%. In one embodiment, the Zn content is from 0.03 wt% to 1.0 wt%. In one embodiment, the Zn content is at least 0.05%, or at least 0.10%, or at least 0.15%, or at least 0.20%, or at least 0.25%, or at least 0.30%, or at least 0.35%, or at least 0.40%, or at least 0.45%, or at least 0.50%, or at least 0.55%, or at least 0.60%, or at least 0.65%, or at least 0.70%, or at least 0.75%, or at least 0.80%, or at least 0.85%, or at least 0.90%, and / or at most 0.95%, or at most 0.90%, or at most 0.85%, or at most 0.80%, or at most 0.75%, or at most 0.70%, or at most 0.65%, or at most 0.60%, or at most 0.55%, or at most 0.50%, or at most 0.45%, or at most 0.40%, or at most 0.35%, or at most 0.30%, or at most 0.25%, or at most 0.20%, or at most 0.15%, or at most 0.10%.

[0064] The Cr content is at most 0.25 wt%. In one embodiment, the Cr content is from 0.01 wt% to 0.25 wt%. In one embodiment, the Cr content is at least 0.02%, or at least 0.03%, or at least 0.04%, or at least 0.05%, or at least 0.06%, or at least 0.07%, or at least 0.08%, or at least 0.09%, or at least 0.10%, or at least 0.11%, or at least 0.12%, or at least 0.13%, or at least 0.14%, or at least 0.15%, or at least 0.16%, or at least 0.17%, or at least 0.18%, or at least 0.19%, or at least 0.20%, or at least 0.21%, or at least 0.22%, or at least 0.23%, and / or at most 0.24%, or at most 0.23%, or at most 0.22%, or at most 0.21%, or at most 0.20%, or at most 0.19%, or at most 0.18%, or at most 0.17%, or at most 0.16%, or at most 0.15%, or at most 0.14%, or at most 0.13%, or at most 0.12%, or at most 0.11%, or at most 0.10%, or at most 0.09%, or at most 0.08%, or at most 0.07%, or at most 0.06%, or at most 0.05%, or at most 0.04%, or at most 0.03%.

[0065] The other elements are inevitable impurities, and their contents are usually at most 0.05% by weight, or at most 0.04% by weight, or at most 0.03% by weight, or at most 0.02% by weight, or at most 0.01% by weight. It should generally be understood that the maximum content relates to each inevitable impurity. Advantageously, the total amount of inevitable impurities is at most 0.15% by weight, or at most 0.12% by weight, at most 0.10% by weight, at most 0.08% by weight, at most 0.06% by weight. In one embodiment, among the inevitable impurities, the Sc content is at most 0.020% by weight, or at most 0.015% by weight, or at most 0.0010% by weight, or at most 0.005% by weight, or at most 0.002% by weight.

[0066] The balance is aluminum.

[0067] In one embodiment of the present invention, the alloy comprises at least two elements selected from Co, Ni, Ba, La, Ce, Ta, Ru, Os, and Zr. If the elements are selected, the content of the elements is 0.003% by weight to 0.15% by weight, the sum of the contents of the selected elements is at least equal to 0.08% by weight, and the content of at least one of the selected elements is 0.04% by weight to 0.15% by weight, preferably 0.05% by weight to 0.10% by weight.

[0068] In one embodiment of the present invention, the alloy comprises at least three elements selected from Co, Ni, Ba, La, Ce, Ta, Ru, Os, and Zr. If the elements are selected, the content of the elements is 0.003% by weight to 0.15% by weight, the sum of the contents of the selected elements is at least equal to 0.014% by weight, and the content of at least one of the selected elements is 0.04% by weight to 0.15% by weight. Preferably, in this embodiment, the selected elements are Co, Ba, Zr or Ni, Ba, Zr or Co, La, Zr or Co, Ni, Ba.

[0069] Compared with the alloys of the prior art, the alloy of the present invention has the advantages of reduced average size and average spacing of intermetallic particles. When the intermetallic particles are small in size and slightly separated from each other, they are less harmful, especially for forming. Therefore, the alloy of the present invention is beneficial to reducing the duration of processes (such as homogenization), improving forming-related properties (such as elongation and formability), and improving surface properties (such as anodic oxidation response).

[0070] One object of the present invention is a heat-treated forged product comprising the alloy of the present invention. In the context of the present invention, a heat-treated product shall be understood as a product in the T state, and a product in the T state refers to a heat-treated alloy product that has been heat-treated to obtain a stable state other than F, O or H. Typically, the heat-treated product is in the T3, T4, T5, T6, T7 or T8 state.

[0071] Another object of the present invention is a rolled product comprising the alloy of the present invention. The thickness of the rolled product of the present invention is typically from 0.5 mm to 300 mm, preferably from 0.8 mm to 150 mm. In an advantageous embodiment, the thickness of the rolled product of the present invention is from 0.8 mm to 1.5 mm, and the folding angle α is determined according to the standards NF EN ISO 7438 and the procedures VDA 238 - 100 and VDA 239 - 200 m to be at least 112°, preferably at least 114°.

[0072] Another object of the present invention is an extruded product comprising the alloy of the present invention. The thickness of the extruded product of the present invention is typically from 0.5 mm to 30 mm, preferably from 0.8 mm to 20 mm. Another object of the present invention is a forged product comprising the alloy of the present invention. Typically, the local thickness of the forged product of the present invention is from 0.5 mm to 300 mm, preferably from 0.8 mm to 150 mm.

[0073] A method for obtaining the heat-treated forged product of the present invention, which comprises the following steps:

[0074] - Supplying pure aluminum or alloy aluminum in the form of a primary metal ingot derived from electrolysis and / or pre-consumer manufacturing waste and / or post-consumer waste, the waste having optionally been melted separately and possibly solidified, and alloying elements in a suitable form;

[0075] - Forming a charge with the supplied aluminum, melting the charge, and adding alloying elements to obtain a liquid alloyed metal bath of the present invention;

[0076] - Casting the liquid metal bath, preferably by direct-chill vertical semi-continuous casting, to obtain a billet suitable for hot working, typically a rolled plate, a forging billet or a bloom;

[0077] - Homogenizing the billet at a temperature of at least 500 °C;

[0078] - Hot working and optionally cold working the billet by rolling, extrusion and / or forging to obtain a forged product;

[0079] - Subjecting the forged product thus obtained to solution heat treatment and quenching at a temperature of at least 500 °C;

[0080] - The solution heat-treated and quenched forged product thus obtained is age-treated and / or tempered at room temperature to obtain a heat-treated forged product.

[0081] In a first step, pure aluminum or aluminum alloy in the form of a primary metal ingot originating from electrolysis and / or pre-consumer manufacturing waste and / or post-consumer waste is supplied, said waste having optionally been melted separately and possibly solidified, and alloying elements in a suitable form.

[0082] Pure aluminum or aluminum alloy in the form of a primary metal ingot generally has the drawback of generating high CO2 emissions during its manufacture, and its use should therefore be limited as much as possible. In the context of the present invention, the term ingot refers to all possible forms of solidified metal. Regarding other metal sources, one can distinguish between pre-consumer manufacturing waste and post-consumer waste, said pre-consumer manufacturing waste being generated before the metal is delivered to the end customer (window trader, vacuum chamber user, car trader, airline, etc.); said post-consumer waste being recycled after product use (typically recovered from cars in a scrapyard). The process of manufacturing aluminum products generates a large amount of pre-consumer manufacturing waste throughout the process. For example, pre-consumer manufacturing waste can include the ends trimmed off a cast plate or billet before hot working, the ends trimmed off a rolled or extruded product during the manufacture of sheet metal or profiles, the frames of blanks for stamping, machining chips, and so on. For example, post-consumer waste includes used window frames, car parts recovered in a scrapyard, crushed motor vehicles, disassembled airplanes, and so on. Post-consumer waste can be supplied in a compacted form, or optionally can be melted separately and possibly solidified. Suitable forms of alloying elements are also supplied. They can consist of elements in metallic form or alloy form. Regarding the addition of rare earth elements such as La, Ce, and Nd, it is advantageous to use mixed rare earth metals as the addition form.

[0083] In a subsequent step, a charge is formed from all or part of the supplied aluminum, the charge is melted and alloying elements are added to obtain a liquid metal bath having the composition of the present invention. Part of the supplied aluminum may already be in liquid form.

[0084] The method of the present invention is advantageous because it can use a high percentage of manufacturing waste and / or post-consumer waste during the formation of the charge. Thus, in one embodiment, the charge comprises at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80% of manufacturing waste. Thus, in one embodiment, the charge comprises at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80% of post-consumer waste. Thus, in one embodiment, the charge comprises at least 20%, or at least 30%, or at least 40%, or at least 50%, or at least 60%, or at least 70%, or at least 80% of manufacturing waste and post-consumer waste. Then, the charge is melted and its composition is adjusted by alloying elements to obtain a liquid metal bath having the composition of the present invention.

[0085] In a subsequent step, the liquid metal bath is preferably cast by direct-chill vertical semi-continuous casting to obtain a billet suitable for hot working, typically a rolled plate or a square billet.

[0086] In a subsequent step, the billet thus obtained is homogenized at at least 500 °C. The homogenization time for the entire billet to reach a temperature of at least 500 °C is typically at least 2 hours, or at least 3 hours, or at least 4 hours, or at least 5 hours, or at least 6 hours. In some embodiments, the alloy of the present invention can reduce the homogenization time. Thus, the homogenization time for the entire billet to reach a temperature of at least 500 °C is advantageously at most 12 hours, or at most 11 hours, or at most 10 hours, or at most 9 hours, or at most 8 hours.

[0087] In a subsequent step, the billet thus homogenized is hot worked and optionally cold worked by rolling, extrusion and / or forging to obtain a forged product. The hot working typically starts at a temperature of at least 400 °C. In one embodiment, the billet is optionally cooled from the homogenization temperature to the starting temperature of processing by forced cooling. In another embodiment, after homogenization, the billet is cooled to room temperature and then reheated to reach the starting temperature of hot working.

[0088] In a subsequent step, the forged product thus obtained is solution heat treated and quenched at a temperature of at least 500 °C. Quenching is typically carried out by immersion or spraying with water, however, for some products, especially extrusion products, air quenching can also be considered.

[0089] In an optional subsequent step, the forged product thus solution heat treated and quenched can be cold worked and / or stress relieved.

[0090] In subsequent steps, the solution heat-treated and quenched forging products thus obtained are subjected to room temperature aging and / or tempering to obtain heat-treated forging products.

[0091] In the product uses of the present invention, automotive manufacturing (such as body skins and reinforcements, shock absorption systems, battery boxes), construction (such as frames, joinery, decorative elements, etc.), aerospace manufacturing (such as fuselages, electrical connectors, etc.) and industrial construction (such as towers, vacuum chambers, tracks) can be specifically mentioned.

[0092] Examples

[0093] Example 1

[0094] In this example, parts made of aluminum alloy were cast and homogenized at 540 °C for 8 hours. The grain refiner Al3Ti0.15C was added at a ratio of 1 kg / t. The compositions of the respective parts are listed in Table 1 below.

[0095] [Table 1] - Alloy composition in wt%

[0096] alloy Si Fe Cu Mn Mg Ti Cr Co V Ni Ba Zr C1H 0.7 0.25 0.12 0.18 0.4 0.02 0 0 0 0 0 0 C2H 0.7 0.25 0.12 0.18 0.4 0.02 0.05 0 0 0.05 0.05 0.05 C3H 0.7 0.25 0.5 0.18 0.4 0.08 0 0.05 0.05 0 0.05 0.05 C4H 0.7 0.25 0.5 0.18 0.4 0.08 0.05 0.05 0.05 0.05 0 0 C9H 1.1 0.25 0.12 0.4 0.4 0.02 0.05 0.05 0.05 0 0 0.05 C10H 1.1 0.25 0.12 0.4 0.4 0.02 0 0.05 0.05 0.05 0.05 0 C11H 1.1 0.25 0.5 0.4 0.4 0.08 0.05 0 0 0 0.05 0

[0097] The intermetallic particles of the parts were characterized by scanning electron microscopy over an area of 3,300 x 3,300 μm 2 . Two parameters were characterized by image analysis: the average size of the intermetallic particles and the average spacing of the intermetallic particles. The characterization method is as Figure 5 , 6 and shown in Figure 7. The obtained images of the intermetallic particles BSD (backscattered diffraction) (such as in Figure 5 ) were corrected and binarized ( Figure 6 ), and the image was subjected to at least two consecutive steps of closing operation of the object so as to be able to quantify the size of the intermetallic particles and the spacing of the intermetallic particles ( Figure 7 ). The closing operation steps of the image analysis were carried out to measure the average size of the intermetallic particles and the average spacing of the intermetallic particles.

[0098] Compared with the reference sample C1H, the results are presented in Table 2 and shown in Figure 1 , expressed in %. In fact, expressing the results in percentage is more relevant, and the absolute values may be affected by experimental parameters.

[0099] [Table 2]

[0100] reference Average size (%) Average spacing (%) C1H 100％ 100％ C2H 60％ 80％ C3H 64％ 82％ C4H 76％ 92％ C9H 76％ 86％ C10H 64％ 78％ C11H 91％ 93％

[0101] When the intermetallic particles are small-sized and slightly separated from each other, they are less harmful, especially for forming. In fact, these two parameters are related, the iron content is constant in the tests, and the total volume of the intermetallic particles is basically constant in different tests.

[0102] Example 2

[0103] In this example, a part made of aluminum alloy was cast and homogenized at 540 °C for 8 hours. The grain refiner Al3Ti0.15C was added at a ratio of 1 kg / t. The composition of each part is listed in Table 3 below.

[0104] [Table 3] - Alloy composition in wt%

[0105] alloy Si Fe Cu Mn Mg Ti Cr Co V Ni Ba Zr C5H 0.7 0.5 0.12 0.4 0.4 0.08 0 0 0.05 0.05 0 0.05 C6H 0.7 0.5 0.12 0.4 0.4 0.08 0.05 0 0.05 0 0.05 0 C7H 0.7 0.5 0.5 0.4 0.4 0.02 0 0.05 0 0.05 0.05 0 C8H 0.7 0.5 0.5 0.4 0.4 0.02 0.05 0.05 0 0 0 0.05 C13H 1.1 0.5 0.12 0.18 0.4 0.08 0.05 0.05 0 0.05 0 0 C14H 1.1 0.5 0.12 0.18 0.4 0.08 0 0.05 0 0 0.05 0.05 C15H 1.1 0.5 0.5 0.18 0.4 0.02 0.05 0 0.05 0.05 0.05 0.05 C16H 1.1 0.5 0.5 0.18 0.4 0.02 0 0 0.05 0 0 0

[0106] The intermetallic particles of the parts have been characterized by scanning electron microscopy over an area of 3,300 x 3,300 μm 2 Two parameters have been characterized by image analysis: the average size of the intermetallic particles and the average spacing of the intermetallic particles.

[0107] Compared with the reference sample C16H, the results are presented in Table 4 and shown in Figure 2 in %, actually, presenting the results in percentage is more relevant, and the absolute values may be affected by the experimental parameters.

[0108] [Table 4]

[0109] alloy Average size (%) Average spacing (%) C5H 70％ 84％ C6H 97％ 86％ C7H 84％ 83％ C8H 85％ 83％ C13H 69％ 87％ C14H 28％ 50％ C15H 70％ 86％ C16H 100％ 100％

[0110] When the intermetallic particles are small-sized and slightly separated from each other, they are less harmful, especially for forming. In fact, these two parameters are related, the iron content is constant in the tests, and the total volume of the intermetallic particles is basically constant in different tests.

[0111] Example 3

[0112] In this example, a part made of aluminum alloy was cast and homogenized at 540 °C for 8 hours. The grain refiner Al3Ti0.15C was added at a ratio of 1 kg / t. The composition of each part is listed in Table 5 below.

[0113] [Table 5] - Alloy composition in wt%

[0114] alloy Si Fe Cu Mn Mg Ti Cr Co V Ni Ba Zr La D12 1.1 0.5 0.12 0.18 0.4 0.03 0.035 0.025 0.025 0.025 0.025 0.025 D17 1.1 0.5 0.12 0.18 0.4 0.03 0.035 0.05 0.050 D18 1.1 0.5 0.12 0.18 0.4 0.03 0.035 0.05 0.050 D19 1.1 0.5 0.12 0.18 0.4 0.03 0.035 0.05 0.05 D4 1.1 0.5 0.12 0.18 0.4 0.03 0.035 D7 1.1 0.5 0.12 0.18 0.4 0.03 0.035 0.05 0.05 0.050

[0115] The intermetallic particles of the parts have been characterized by scanning electron microscopy over an area of 3,300 x 3,300 μm 2Characterization was carried out on an area of... Two parameters were characterized by image analysis: the average size of the intermetallic particles and the average spacing of the intermetallic particles.

[0116] Compared with the reference sample D4, the results are presented in Table 6 and shown in Figure 3 in %, actually, presenting the results in percentage is more relevant, and the absolute values may be affected by experimental parameters.

[0117] [Table 6]

[0118] alloy Average size (%) Average spacing (%) D12 90％ 90％ D17 73％ 84％ D18 76％ 87％ D19 79％ 81％ D4 100％ 100％ D7 68％ 84％

[0119] Example 4

[0120] In this example, parts made of aluminum alloy were cast and homogenized at 540 °C for 8 hours. The grain refiner Al3Ti0.15C was added at a ratio of 1 kg / t. The composition of each part is listed in Table 7 below.

[0121] [Table 7] - Alloy composition in wt%

[0122] alloy Si Fe Cu Mn Mg Ti Cr Co V Ni Ba Zr La D10 1.1 0.5 0.12 0.18 0.4 0.08 0.035 0.05 0.050 0.05 D13 1.1 0.5 0.12 0.18 0.4 0.08 0.200 0.05 0.05 D16 1.1 0.5 0.12 0.18 0.4 0.08 0.200 0.05 D5 1.1 0.5 0.12 0.18 0.4 0.08 0.035 D8 1.1 0.5 0.12 0.18 0.4 0.08 0.035 0.05 0.025 0.025

[0123] The intermetallic particles of the parts have been characterized by scanning electron microscopy on an area of 3,300 x 3,300 μm 2 Characterization was carried out on an area of... Two parameters were characterized by image analysis: the average size of the intermetallic particles and the average spacing of the intermetallic particles.

[0124] Compared with the reference sample D5, the results are presented in Table 8 and shown in Figure 4 in %, actually, presenting the results in percentage is more relevant, and the absolute values may be affected by experimental parameters.

[0125] [Table 8]

[0126] alloy Average size (%) Average spacing (%) D10 73％ 84％ D13 80％ 83％ D16 90％ 88％ D5 100％ 100％ D8 76％ 87％

[0127] When the intermetallic particles are small in size and slightly separated from each other, they are less harmful, especially for forming. Actually, these two parameters are related, the iron content is constant in the tests, and the total volume of the intermetallic particles is basically constant in different tests.

[0128] Example 5

[0129] In this example, parts made of aluminum alloy 6082 were cast, 1 wt% of iron was added to these parts, and 0.2 wt% of La was added to one of the parts tested.

[0130] The intermetallic particles of the parts were characterized by optical microscopy. The results of adding La are shown inFigure 8 In [reference], the results without the addition of La are shown in Figure 9 [reference]. Compared with the reference without La, in the case of adding La, the intermetallic particles have smaller sizes, and their distribution is refined by 35%.

[0131] Example 6

[0132] In this example, an industrial standard plate made of aluminum alloy was cast. The grain refiner Al3Ti0.15C was added at a ratio of 1 kg / t. The composition of the plate is listed in Table 9 below. These three alloys are in line with the registration of alloy AA6016A. However, the iron content of alloy E1 is the typical standard industrial content, while the iron contents of alloys E2 and E3 are typical alloys containing high levels of recycled materials.

[0133] [Table 9] - Alloy composition in wt%

[0134] alloy Si Fe Cu Mn Mg Ti Cr Co Zr E1 0.90 0.25 0.09 0.17 0.41 0.04 0.04 E2 0.90 0.37 0.09 0.17 0.41 0.04 0.04 E3 0.90 0.37 0.09 0.17 0.41 0.04 0.04 0.05 0.05

[0135] The plate was homogenized at 560 °C for 3 hours, then homogenized at 535 °C for 1 hour, and then hot-rolled and cold-rolled to obtain a metal sheet with a thickness of 1.2 mm.

[0136] The metal sheet with a thickness of 1.2 mm was solution heat-treated at 520 °C for 1 hour, quenched, pre-tempered at 85 °C for 8 hours, and aged at room temperature for 21 days. The mechanical properties of these metal sheets under the folding tests according to the standards NF EN ISO 7438 and procedures VDA238-100 and VDA 239-200 were characterized in the transverse direction relative to the rolling direction after pre-stretching by 14%.

[0137] The obtained results are listed in Table 10.

[0138] [Table 10] - Folding test results

[0139]

[0140] Due to the addition of Co and Zr, the foldability of the AA6016A alloy with a high iron content can be restored to the folding performance of the AA6016A alloy with a standard iron content.

Claims

1. An aluminum-based alloy, which contains by weight %: - Mg: 0.2 - 1.5; - Si: 0.3 - 2.0; - Fe: 0.30 - 1.0; - Ti: 0.01 - 0.15; - At least one element selected from Co, Ba, Ni, La, Ce, Ta, Mo, W, Nb, Re, Pr, Nd, Pm, Sm, Y, Ru, Os, if this element is selected, its content is 0.003 to 0.20, preferably 0.005 to 0.15, -Zr:≤0.15； - Mn: ≤1.5; -V:≤0.20； - Zn: ≤1.0; -Cr:≤0.25； - Cu: ≤1.5; - The balance is aluminum and unavoidable impurities, and the content of impurities is at most 0.05% by weight.

2. The alloy according to claim 1, which contains by weight %: Zr: 0.003 - 0.15 and / or Mn: 0.03 - 1.0 and / or V: 0.05 - 0.20 and / or Zn: 0.03 - 1.0 and / or Cr: 0.01 - 0.25 and / or Cu: 0.05 - 1.

0.

3. The alloy according to claim 1 or claim 2, wherein the alloy contains at least two elements selected from Co, Ni, Ba, La, Ce, Ta, Ru, Os and Zr, if this element is selected, the content of this element is 0.003% by weight to 0.15% by weight; the sum of the contents of the selected elements is at least equal to 0.08% by weight, and the content of at least one of the selected elements is 0.04% by weight to 0.15% by weight.

4. The alloy according to any one of claims 1 to 3, wherein the alloy contains at least three elements selected from Co, Ni, Ba, La, Ce, Ta, Ru, Os and Zr, if this element is selected, the content of this element is 0.003% by weight to 0.15% by weight; the sum of the contents of the selected elements is at least equal to 0.014% by weight, and the content of at least one of the selected elements is 0.04% by weight to 0.15% by weight.

5. The alloy according to claim 4, wherein the selected elements are Co, Ba, Zr or Ni, Ba, Zr or Co, La, Zr or Co, Ni, Ba.

6. The alloy according to any one of claims 1 to 5, wherein the content of Fe is 0.35% by weight to 0.85% by weight, preferably 0.4% by weight to 0.7% by weight.

7. A heat-treated forging product, which contains the alloy according to any one of claims 1 to 6.

8. The forging product according to claim 7, wherein the forging product is a rolled product with a thickness of 0.5 mm to 300 mm, preferably 0.8 mm to 150 mm.

9. The forging product according to claim 8, characterized in that, Its thickness ranges from 0.8 mm to 1.5 mm, and its folding angle α is determined according to the standards NF EN ISO 7438 and the procedures VDA 238-100 and VDA 239-200 m is at least 112°, preferably at least 114°.

10. The forging product according to claim 7, wherein the forging product is an extruded product with a thickness of 0.5 mm to 30 mm, preferably 0.8 mm to 20 mm.

11. The forging product according to claim 7, wherein the forging product is a forged product with a local thickness of 0.5 mm to 300 mm, preferably 0.8 mm to 150 mm.

12. A method for manufacturing the product according to any one of claims 7 to 11, comprising the following steps: - Supplying pure aluminum or aluminum alloy in the form of a primary metal ingot derived from electrolysis and / or pre-consumer manufacturing waste and / or post-consumer waste, said waste optionally having been melted separately and possibly solidified, and alloying elements in a suitable form; - Forming a charge with the supplied aluminum, melting the charge, and adding alloying elements to obtain a liquid alloyed metal bath according to the invention; - Casting the liquid metal bath, preferably by direct-chill vertical semi-continuous casting; To obtain a billet suitable for hot working, typically a rolled plate, a forging billet or a square billet; - Homogenizing the billet at a temperature of at least 500 °C; - Hot working and optionally cold working the billet by rolling, extrusion and / or forging; To obtain a forged product; - Subjecting the forged product thus obtained to solution heat treatment and quenching at a temperature of at least 500 °C; - Aging and / or tempering the solution heat treated and quenched forged product thus obtained at room temperature to obtain a heat treated forged product.

13. The method according to claim 12, wherein the charge contains at least 30% of post-consumer waste.

14. The method according to claim 12 or claim 13, wherein titanium is added in the form of metallic titanium and TiC.

15. Use of the product according to any one of claims 7 to 11 for automotive manufacturing, construction, aviation manufacturing or industrial construction.

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