Method for manufacturing an aluminum alloy part

Abstract

An additive manufacturing method applied to an aluminium alloy comprising the following alloying elements (in wt.%): - at least one alloying element chosen from: - Zr, Hf, Sc and Er, in a mass fraction of 0.40 to 1.60%; - Fe, in a mass fraction of 0.03 to 1.85%; - Mg, in a mass fraction of 2.50 to 3.95%.

Description

[0001] DESCRIPTION

[0002] Title: PROCESS FOR MANUFACTURING AN ALUMINUM ALLOY PART

[0003] Technical field

[0004] The technical field of the invention is a method of manufacturing an aluminum alloy part, using an additive manufacturing technique.

[0005] Prior art

[0006] Since the 1980s, additive manufacturing techniques have been developing. They involve shaping a part by adding material, which is the opposite of machining techniques, which aim to remove material. Once limited to prototyping, additive manufacturing is now operational for mass-producing industrial products, including metal parts.

[0007] The term "additive manufacturing" is defined according to the French standard XP E67-001 as a "set of processes for manufacturing, layer by layer, by adding material, a physical object from a digital object". The ASTM F2792 standard (January 2012) also defines additive manufacturing. Different additive manufacturing methods are also defined and described in the ISO / ASTM 17296-1 standard. The use of additive manufacturing to produce an aluminum part with low porosity was described in document W02015006447. The application of successive layers is generally carried out by applying a so-called filler material, then melting or sintering the filler material using an energy source such as a laser beam, electron beam, plasma torch or electric arc. Regardless of the additive manufacturing method applied, the thickness of each added layer is of the order of a few tens or hundreds of microns.

[0008] Other additive manufacturing methods can be used. For example, but not limited to, the melting or sintering of a filler material in the form of a powder. This may involve laser melting or sintering. Patent application US20170016096 describes a method for manufacturing a part by localized melting obtained by exposing a powder to an energy beam such as an electron beam or a laser beam, the method also being referred to as laser powder bed fusion or electron beam melting. The powder consists of an aluminum alloy with a copper content of 5 to 6% by mass, and a magnesium content of 2.5 to 3.5% by mass.

[0009] WO2018185259 describes an alloy, intended to be used in the form of a powder, in an additive manufacturing process of the laser powder bed fusion type. The alloy may in particular contain from 2 to 7% by mass of Mg. It may also contain a mass fraction of Zr of 0 to 1%.

[0010] Document WO2018009359 describes an aluminum alloy, in powder form, comprising a mass fraction of Mg of 1 to 10%, as well as a mass fraction of Zr of 0.3 to 3%. The alloy may also comprise Zn, Mn, Cr, Si, Fe, Cu, but these elements are then present in the form of unavoidable impurities, the content of which is less than 500 ppm.

[0011] Document WO2020152427 describes an aluminum alloy comprising from 0 to 6% of Mg, from 0.7 to 2.5% of Zr and at least one alloying element chosen from: Fe, Cu, Mn, Ni and La, according to a mass fraction of at least 0.1%.

[0012] WO2021099735 describes an aluminum alloy comprising 2.0-5.0% Mg, 0.5-1.0% Zr and 0.6-3.0% Fe.

[0013] The mechanical properties of aluminum parts obtained by additive manufacturing depend on the alloy forming the filler metal, and more precisely on its composition as well as the heat treatments applied following the implementation of additive manufacturing.

[0014] The applicant has determined an alloy composition which, when used in an additive manufacturing process, makes it possible to obtain parts with remarkable mechanical performance, without it being necessary to implement heat treatments such as solution treatment and quenching.

[0015] According to a variant of the present invention, with a judicious choice of the addition elements, the applicant has identified aluminum alloy compositions intended for additive manufacturing processes, in particular laser powder bed fusion, these compositions make it possible to obtain both very good processability of the parts in the laser powder bed fusion process, and excellent mechanical performance of the parts in service. The excellent mechanical performance of the parts in service is obtained by maximizing the elastic limit of the parts at room temperature after post-manufacturing heat treatment (for example elastic limit Rp0.2 greater than or equal to 360 MPa, preferably greater than or equal to 370 MPa, preferably greater than or equal to 370 MPa, preferably greater than or equal to 380 MPa).

[0016] Pure aluminum powders can be used as a reducing agent in solid aerospace propellant. Therefore, aluminum powders with more than 97% aluminum are generally considered dual-use goods (DUGs) in some countries, requiring export licenses. This classification represents a constraint that can hinder the commercialization of certain aluminum powders containing more than 97% aluminum intended for additive manufacturing processes, such as laser powder bed fusion. It therefore appears advantageous for the developed solution to contain less than 97% aluminum, i.e., more than 3% additive elements in total.

[0017] According to another variant of the present invention, with a judicious choice of the additive elements, the applicant has identified aluminum alloy compositions intended for additive manufacturing processes, in particular laser powder bed fusion, these compositions comprising more than 3% of additive elements in total and allowing good processability of the parts in the laser powder bed fusion process, while maximizing the mechanical performance of the parts in service.

[0018] Statement of the invention

[0019] A first subject of the invention is a method of manufacturing a part comprising a formation of successive metallic layers, superimposed on each other, each layer being formed by the deposition of a filler metal, the filler metal being subjected to an energy input so as to melt and to constitute, by solidifying, said layer, the method being characterized in that the filler metal is an aluminum alloy comprising the following alloying elements in mass percentages:

[0020] - at least one alloying element chosen from: Zr, Hf, Sc and Er, according to a mass fraction of 0.40 to 1.60%, preferably 0.50 to 1.50%, preferably 0.60 to 1.45%, preferably 0.7 to 1.40%, preferably 0.80 to 1.40%, preferably 0.85 to 1.35% each and / or in total;

[0021] - Fe, in a mass fraction of 0.03 to 1.85%, preferably 0.05 to 1.85%, preferably 0.10 to 1.85%, preferably 0.15 to 1.80%, preferably 0.20 to 1.70%, preferably 0.30 to 1.60%, preferably 0.40 to 1.50%, preferably 0.50 to 1.50%, preferably 0.60 to 1.50%, preferably 0.70 to 1.50%, preferably 0.80 to 1.50%, -

[0022] - Mg, in a mass fraction of 2.50 to 3.95%, preferably 2.60 to 3.90%, preferably 2.70 to 3.80%, preferably 2.70 to 3.70%, preferably 2.70 to 3.60%, preferably 2.80 to 3.60%, preferably 2.80 to 3.50%, preferably 2.90 to 3.40%, -

[0023] - at least one alloying element chosen from Cr, V and Ti, according to a mass fraction greater than or equal to 0.10%, preferably greater than or equal to 0.20%, preferably greater than or equal to 0.30%, preferably greater than or equal to 0.40%, preferably greater than or equal to 0.50%, preferably from 0.50 to 3.00%, preferably from 0.60 to 2.90%, preferably from 0.70 to 2.80%, preferably from 0.80 to 2.70%, preferably from 0.80 to 2.60%, preferably from 0.80 to 2.50%, preferably from 0.85 to 2.45%, preferably from 0.90 to 2.40%, each and / or in total;- optionally Mn, according to a mass fraction greater than or equal to 0.10%, preferably greater than or equal to 0.20%, preferably greater than or equal to 0.30%, preferably greater than or equal to 0.40%, preferably greater than or equal to 0.50%, preferably from 0.50 to 3.00%, preferably from 0.60 to 2.90%, preferably from 0.70 to 2.80%, preferably from 0.80 to 2.70%, preferably from 0.80 to 2.60%, preferably from 0.80 to 2.50%, preferably from 0.85 to 2.45%, preferably from 0.90 to 2.40%, -;

[0024] - optionally Ni, according to a mass fraction less than or equal to 3.00%, preferably less than or equal to 2.50%, preferably less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%;

[0025] - optionally at least one alloying element chosen from: Cu and Ag, according to a mass fraction of 0.05 to 2.00%, preferably 0.10 to 2.00%, preferably 0.10 to 1.60%, preferably 0.10 to 1.00%, preferably 0.10 to 0.70% for Cu; according to a mass fraction of 0.05 to 3.00%, preferably 0.10 to 3.00%, preferably 0.10 to 2.00%, preferably 0.10 to 1.60%, preferably 0.10 to 1.00%, preferably 0.10 to 0.70% for Ag and / or in total;

[0026] - optionally If, according to a mass fraction less than or equal to 3.00%, preferably less than or equal to 2.50%, preferably less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.20%;

[0027] - optionally one element from Zn and Li, according to a mass fraction less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30% each and / or in total;

[0028] - optionally at least one element chosen from: Co, La, Ce, mischmetal, W, Ta, Mo and Nb, Nd, Y, Tm, Lu, Yb, Sr, Ba, Sb, Bi, Ca, P, B, In and Sn, according to a mass fraction less than or equal to 2.00%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30%, preferably less than or equal to 0.10% each, and less than or equal to 2.00%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30% in total;

[0029] - impurities: < 0.05% individually, and preferably < 0.15% in total; remainder aluminum.

[0030] Each layer can notably describe a pattern defined from a digital model.

[0031] According to one embodiment, the filler metal takes the form of a powder, the exposure of which to a beam of light or charged particles results in localized melting followed by solidification, so as to form a solid layer. According to another embodiment, the filler metal is derived from a filler wire, the exposure of which to a heat source, for example an electric arc, results in localized melting followed by solidification, so as to form a solid layer.

[0032] A second object of the invention is a metal part, obtained by a method according to the first object of the invention.

[0033] A third subject of the invention is a filler material, in particular a filler wire or a powder, intended to be used as a filler material in an additive manufacturing process, characterized in that it consists of an aluminum alloy, comprising the following alloying elements (% by weight):

[0034] - at least one alloying element chosen from: Zr, Hf, Sc and Er, according to a mass fraction of 0.40 to 1.60%, preferably 0.50 to 1.50%, preferably 0.60 to 1.45%, preferably 0.7 to 1.40%, preferably 0.80 to 1.40%, preferably 0.85 to 1.35% each and / or in total;

[0035] - Fe, in a mass fraction of 0.03 to 1.85%, preferably 0.05 to 1.85%, preferably 0.10 to 1.85%, preferably 0.15 to 1.80%, preferably 0.20 to 1.70%, preferably 0.30 to 1.60%, preferably 0.40 to 1.50%, preferably 0.50 to 1.50%, preferably 0.60 to 1.50%, preferably 0.70 to 1.50%, preferably 0.80 to 1.50%, -

[0036] - Mg, in a mass fraction of 2.50 to 3.95%, preferably 2.60 to 3.90%, preferably 2.70 to 3.80%, preferably 2.70 to 3.70%, preferably 2.70 to 3.60%, preferably 2.80 to 3.60%, preferably 2.80 to 3.50%, preferably 2.90 to 3.40%, -

[0037] - at least one alloying element chosen from Cr, V and Ti, according to a mass fraction greater than or equal to 0.10%, preferably greater than or equal to 0.20%, preferably greater than or equal to 0.30%, preferably greater than or equal to 0.40%, preferably greater than or equal to 0.50%, preferably from 0.50 to 3.00%, preferably from 0.60 to 2.90%, preferably from 0.70 to 2.80%, preferably from 0.80 to 2.70%, preferably from 0.80 to 2.60%, preferably from 0.80 to 2.50%, preferably from 0.85 to 2.45%, preferably from 0.90 to 2.40%, each and / or in total;

[0038] - optionally Mn, according to a mass fraction greater than or equal to 0.10%, preferably greater than or equal to 0.20%, preferably greater than or equal to 0.30%, preferably greater than or equal to 0.40%, preferably greater than or equal to 0.50%, preferably from 0.50 to 3.00%, preferably from 0.60 to 2.90%, preferably from 0.70 to 2.80%, preferably from 0.80 to 2.70%, preferably from 0.80 to 2.60%, preferably from 0.80 to 2.50%, preferably from 0.85 to 2.45%, preferably from 0.90 to 2.40%, - - optionally Ni, according to a mass fraction less than or equal to 3.00%, preferably less than or equal to 2.50%, preferably less than or equal to 2.00%, preferably less than or equal to at 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%;

[0039] - optionally at least one alloying element chosen from: Cu and Ag, according to a mass fraction of 0.05 to 2.00%, preferably of 0.10 to 2.00%, preferably of

[0040] 0.10 to 1.60%, preferably 0.10 to 1.00%, preferably 0.10 to 0.70% for Cu; in a mass fraction of 0.05 to 3.00%, preferably 0.10 to 3.00%, preferably

[0041] 0.10 to 2.00%, preferably 0.10 to 1.60%, preferably 0.10 to 1.00%, preferably

[0042] 0.10 to 0.70% for Ag and / or in total;

[0043] - optionally If, according to a mass fraction less than or equal to 3.00%, preferably less than or equal to 2.50%, preferably less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.20%;

[0044] - optionally one element from Zn and Li, according to a mass fraction less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30% each and / or in total;

[0045] - optionally at least one element chosen from: Co, La, Ce, mischmetal, W, Ta, Mo and Nb, Nd, Y, Tm, Lu, Yb, Sr, Ba, Sb, Bi, Ca, P, B, In and Sn, according to a mass fraction less than or equal to 2.00%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30%, preferably less than or equal to 0.10% each, and less than or equal to 2.00%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30% in total;

[0046] - impurities: < 0.05% individually, and in total < 0.15%; remainder aluminum.

[0047] The aluminum alloy forming the filler material may have the characteristics described in connection with the first subject of the invention.

[0048] The filler material may be in the form of a powder. The powder may be such that at least 80% of the particles comprising the powder have an average size in the following range: 5 pm to 200 pm, preferably 5 to 150 pm, preferably 5 to 25 pm, or 20 to 60 pm or 20 to 80 pm or 20 to 90 pm or 20 to 100 pm or 20 to 110 pm or 20 to 120 pm.

[0049] When the filler material is in the form of a wire, the diameter of the wire may in particular be from 0.5 mm to 3 mm, and preferably from 0.5 mm to 2 mm, and more preferably from 1 mm to 2 mm.

[0050] A fourth object of the invention is the use of a powder or a filler wire as described above and in the rest of the description in a manufacturing process chosen from: electron beam melting, cold spraying, laser fusion deposition, additive manufacturing by friction, plasma spark sintering or rotary friction welding, preferably cold spraying.

[0051] Other advantages and characteristics will emerge more clearly from the following description of particular embodiments of the invention, given as non-limiting examples, and represented in the figures listed below.

[0052] Figures

[0053] [Fig. 1] Figure 1 is a schematic diagram illustrating a laser powder bed fusion additive manufacturing process.

[0054] [Fig. 2] Figure 2 is a schematic diagram illustrating a wire arc additive manufacturing process.

[0055] [Fig. 3] Figure 3 shows a cracking specimen as used in the examples. Reference 1 corresponds to the face used for metallographic observations, reference 2 to the manufacturing direction.

[0056] [Fig. 4] Figure 4 is a diagram of the test piece used according to the examples.

[0057] Presentation of specific embodiments

[0058] In the description, unless otherwise indicated:

[0059] - the designation of aluminum alloys is in accordance with the nomenclature of The Aluminum Association;

[0060] - the contents of chemical elements are designated in % and represent mass fractions. The notation x% - y% means greater than or equal to x% and less than or equal to y%.

[0061] Impurities are chemical elements present in the alloy unintentionally, preferably in a mass fraction of less than 0.05%.

[0062] According to the present invention, the expression "at least one alloying element chosen from: X, Y (...) and Z" means that each of the elements cited may be present, alone or in combination with any one or any of the other elements, according to the specified mass fractions. This expression therefore covers each of the elements cited and all their possible combinations.

[0063] According to the present invention, the optional elements are:

[0064] - either absent, i.e. considered as an unintentional impurity according to a mass fraction of less than 0.05%,

[0065] - either present according to the specified mass fractions.

[0066] Figure 1 shows schematically the operation of an additive manufacturing process of the selective laser melting type (Laser Powder Bed Fusion). The filler metal 15 is in the form of a powder arranged on a support 10. An energy source, in this case a laser source 11, emits a laser beam 12. The laser source is coupled to the filler material by an optical system 13, the movement of which is determined according to a digital model M. The laser beam 12 propagates along a propagation axis Z, and follows a movement along an XY plane, describing a pattern depending on the digital model M. The plane is for example perpendicular to the propagation axis Z. The interaction of the laser beam 12 with the powder 15 causes a selective melting of the latter, followed by solidification, resulting in the formation of a layer 20i...20 n. When a layer has been formed, it is covered with powder 15 of the filler metal and another layer is formed, superimposed on the layer previously produced. The thickness of a layer can for example be from 10 to 250 pm, for example 30 pm, or 60 pm, or 80 pm, or 90 pm, or 100 pm, or 110 pm, or 120 pm, or 130 pm, or 140 pm, or 150 pm, or 160 pm, or 170 pm, or 180 pm, or 190 pm, or 200 pm.

[0067] An increase in layer thickness can be beneficial to increase productivity during printing and to limit sensitivity to thermal cracking related to residual stresses during part manufacturing and / or during post-manufacturing heat treatment. An increase in layer thickness can be accompanied by an adaptation of the laser power and the vector gap (distance between two successive laser passes) and the laser scanning speed in order to ensure complete melting of each powder layer under optimal conditions. The layer thickness can be for example from 60 to 250 pm, preferably from 80 to 200 pm, preferably from 90 to 180 pm, preferably from 100 to 180 pm, preferably from 110 to 170 pm, preferably from 120 to 160 pm.

[0068] For aluminum alloys, the support 10 or platen can be heated to a preheating temperature T of up to 500°C. Machines currently available on the market generally offer platen heating up to 200°C. The platen heating temperature (= preheating temperature T) can be, for example, approximately 50°C, 100°C, 150°C, 200°C, 250°C, 300°C or 350°C or 400°C or 450°C or 500°C. Heating the platen generally reduces the humidity in the powder bed and also reduces residual stresses on the parts being manufactured. The humidity level in the powder bed seems to have a direct effect on the porosity of the final part. Indeed, it would seem that the higher the humidity of the powder, the higher the porosity of the final part. It should be noted that heating the plate is one of the existing possibilities for carrying out hot additive manufacturing.However, the present invention cannot be limited to the use of this heating means alone. Any other heating means, making it possible to carry out this preheating step, can be used within the scope of the present invention to heat and control the temperature, for example an infrared lamp. Thus, the method according to the present invention can be carried out at a preheating temperature T of up to 500°C.

[0069] For certain compositions, the inventors have found that when the preheating temperature T of the powder bed is less than or equal to 160°C and greater than or equal to 25°C, the parts have better resistance to thermal cracking linked to residual stresses. Preferably, the preheating of the powder bed can be carried out at a preheating temperature T less than or equal to 140°C, or, better, less than or equal to 130°C. The preheating temperature T is higher than ambient temperature. The preferred preheating temperature ranges T of the powder bed are: 25°C < T < 160°C, preferably 30°C < T < 150°C, preferably 50°C < T < 150°C, preferably 50°C < T < 140°C, preferably 60°C < T < 140°C, preferably 70°C < T < 135°C, preferably 80°C < T < 130°C.

[0070] Alternatively, the preheating temperature T corresponds to the conditions under which effective stress relief can be achieved. The preheating temperature range T may then be from 300°C to 500°C, preferably from 300 to 400°C, preferably from 300 to 350°C. It is considered that at this preheating temperature range T, the manufacturing conditions of the part generate fewer residual stresses. According to this alternative, a post-manufacturing stress relief heat treatment, as described below in this description, is also relevant.

[0071] The powder according to the present invention may have at least one of the following characteristics:

[0072] - Average particle size from 5 pm to 200 pm, preferably from 5 to 150 pm, preferably from 5 to 25 pm, or from 20 to 60 pm, or from 20 to 80 pm, or from 20 to 90 pm, or from 20 to 100 pm, or from 20 to 110 pm, or from 20 to 120 pm. The given values ​​mean that at least 80% of the particles have an average size in the specified range.

[0073] Spherical shape. The sphericity of a powder can, for example, be determined using a morphogranulometer.

[0074] - Good flowability. The flowability of a powder can, for example, be determined according to ASTM B213 or ISO 4490:2018. According to ISO 4490:2018, the flow time is preferably less than 50.

[0075] - Low porosity, preferably 0 to 5%, more preferably 0 to 2%, even more preferably 0 to 1% by volume. Porosity can be determined, in particular, by image analysis from optical micrographs or by helium pycnometry (see ASTM B923).

[0076] - Absence or low quantity (less than 10%, preferably less than 5% by volume) of small particles (1 to 20% of the average size of the powder), called satellites, which stick to the larger particles.

[0077] The implementation of such a process allows the production of parts with a high yield, which can reach or even exceed 200 cm 3 / h per laser.

[0078] Furthermore, the applicant observed that the application of post-manufacturing heat treatments such as quenching could cause distortion of the part, due to the sudden temperature variation. The distortion of the part is generally all the more significant as its dimensions are large. However, the advantage of an additive manufacturing process is precisely to obtain a part whose shape, after manufacturing, is definitive or quasi-definitive. The occurrence of significant deformation resulting from a post-manufacturing heat treatment is therefore to be avoided. By quasi-definitive, it is understood that finishing machining can be carried out on the part after its manufacturing: the part manufactured by additive manufacturing extends according to its definitive shape, apart from the finishing machining.

[0079] Having noted the above, the applicant sought an alloy composition, forming the filler material, making it possible to obtain acceptable mechanical properties and electrical or thermal conductivity, without requiring the application of heat treatments, subsequent to the formation of the layers, that is to say following the formation of the final part, which risk inducing distortion. This involves in particular avoiding heat treatments involving a sudden variation in temperature. Thus, the invention makes it possible to obtain, by additive manufacturing, a part whose mechanical properties, in particular in terms of elastic limit, and electrical or thermal conductivity, are satisfactory. Depending on the type of additive manufacturing process chosen, the filler material may be in the form of a wire or a powder.

[0080] The following elements can be used in the aluminum alloy: Zr, Hf, Sc and / or Er:

[0081] According to the present invention, at least one alloying element selected from: Zr, Hf, Sc and Er is present in the aluminum alloy in a mass fraction of 0.40 to 1.60%, preferably 0.50 to 1.50%, preferably 0.60 to 1.45%, preferably 0.7 to 1.40%, preferably 0.80 to 1.40%, preferably 0.85 to 1.35% each and / or in total. In one embodiment, the mass fraction of at least one alloying element selected from: Zr, Hf, Sc and Er is greater than or equal to 0.40%, or 0.45%, or 0.50%, or 0.55%, or 0.60%, or 0.65%, or 0.70%, or 0.75%, or 0.80%, or 0.85% each and / or in total. In one embodiment, the mass fraction of at least one alloying element selected from: Zr, Hf, Sc and Er is less than or equal to 1.60%, or 1.55%, or 1.50%, or 1.45%, or 1.40%, or 1.35% each and / or in total.

[0082] These elements have a high solubility in the as-manufactured state. Their addition can thus significantly lower the conductivity in the as-manufactured state. However, the addition of a post-manufacture heat treatment, for example at a temperature of 300 to 450°C, for durations of 0.5 to 10 hours, can significantly lower their solid solution contents by the formation of hardening dispersoids of the AI3X type (X = Zr or Hf or Sc or Er). The formation of these dispersoids during the heat treatment can simultaneously increase the hardness and electrical conductivity compared to the as-manufactured state.

[0083] These elements can also help control the granular structure during laser fusion by promoting the appearance of equiaxed grains.

[0084] Furthermore, the presence of at least one alloying element chosen from: Zr, Hf, Sc and / or Er in the alloy can confer good processability of the alloy, the term processability corresponding to the Anglo-Saxon designation "processability", qualifying the ability of an alloy to be shaped by an additive manufacturing process. This can result, at the level of a part manufactured by additive manufacturing, in a virtual absence of defects, such as solidification cracking, and low porosity.

[0085] Fe:

[0086] According to the present invention, the element Fe is present in the aluminum alloy in a mass fraction of 0.03 to 1.85%, preferably 0.05 to 1.85%, preferably 0.10 to 1.85%, preferably 0.15 to 1.80%, preferably 0.20 to 1.70%, preferably 0.30 to 1.60%, preferably 0.40 to 1.50%, preferably 0.50 to 1.50%, preferably 0.60 to 1.50%, preferably 0.70 to 1.50%, preferably 0.80 to 1.50%.

[0087] According to one variant, the mass fraction of Fe is from 0.10 to 1.50%, preferably from 0.15 to 1.50%, preferably from 0.20 to 1.50%, preferably from 0.30 to 1.50%, preferably from 0.30 to 1.30%, preferably from 0.30 to 1.10%, preferably from 0.30 to 1.00%, preferably from 0.30 to 0.80%, preferably from 0.30 to 0.60% each and / or in total.

[0088] In one embodiment, the mass fraction of Fe is greater than or equal to 0.03%, or 0.05%, or 0.10%, or 0.15%, or 0.20%, or 0.25%, or 0.30%, or 0.35%, or 0.40%, or 0.45%, or 0.50%, or 0.55%, or 0.60%, or 0.65%, or 0.70%, or 0.75%, or 0.80%. In one embodiment, the mass fraction of Fe is less than or equal to 1.85%, or 1.80%, or 1.75%, or 1.70%, or 1.65%, or 1.60%, or 1.55%, or 1.50%, or 1.45%, or 1.40%, or 1.35%, or 1.30%, or 1.25%, or 1.20%, or 1.15%, or 1.10%, or 1.15%, or 1.10%, or 1.05%, or 1.00%, or 0.95%, or 0.90%, or 0.85%, or 0.80%, or 0.75%, or 0.70%, or 0.65%, or 0.60%.

[0089] Fe can be used to increase the mechanical strength of the alloy by solid solution and / or by dispersoids that can form during the manufacturing of the part or during post-manufacturing heat treatments. This element has low solubility in aluminum. The addition of this element can increase the yield strength, but excessive addition of Fe, i.e. at contents greater than or equal to 1.90%, can lead to an increase in sensitivity to cracking and lower the elongation at break.

[0090] In the presence of Zr, the addition of Fe at a content greater than or equal to 0.20%, preferably greater than or equal to 0.30%, can significantly suppress or limit the discontinuous precipitation of Zr from the grain boundaries during post-manufacturing heat treatment, for example at 400°C. Without being bound by theory, in the presence of Fe, the Zr trapped in solid solution after printing would precipitate mainly after post-manufacturing heat treatment in the form of spherical nanometric precipitates of the AI3Zr type, which would provide optimal hardening of the alloy. Thus, for a given Zr content, the presence of Fe can maximize the hardening power of Zr via more efficient precipitation during post-manufacturing heat treatment, for example after 4 hours at 400°C.

[0091] Mg:

[0092] According to the present invention, the element Mg is present in the aluminum alloy in a mass fraction of 2.50 to 3.95%, preferably 2.60 to 3.90%, preferably 2.70 to 3.80%, preferably 2.70 to 3.70%, preferably 2.70 to 3.60%, preferably 2.80 to 3.60%, preferably 2.80 to 3.50%, preferably 2.90 to 3.40%. In one embodiment, the mass fraction of Mg is greater than or equal to 2.50%, or 2.55%, or 2.60%, or 2.65%, or 2.70%, or 2.75%, or 2.80%, or 2.85%, or 2.90%. In one embodiment, the mass fraction of Mg is less than or equal to 3.95%, or 3.90%, or 3.85%, or 3.80%, or 3.75%, or 3.70%, or 3.65%, or 3.60%, or 3.55%, or 3.50%, or 3.45%, or 3.40%.

[0093] Mg can increase the mechanical strength of the alloy by solid solution. It can also, counterintuitively, improve crack resistance. Excessive addition of this element, for example at contents greater than or equal to 3.50%, can degrade intergranular corrosion resistance, by the formation of the anodic phase P (Mg5Alg) at the grain boundaries. The formation of this phase can occur at room temperature and its formation can be accelerated at temperatures greater than or equal to 60°C.

[0094] This element is sensitive to evaporation during laser melting, which can lead to the formation of fumes and instabilities in the melt pools. This evaporation must be taken into account when adjusting the Mg content in the powder according to the target Mg content on the part.

[0095] Mn:

[0096] According to the present invention, the element Mn may be present in the aluminum alloy, in a mass fraction greater than or equal to 0.10%, preferably greater than or equal to 0.20%, preferably greater than or equal to 0.30%, preferably greater than or equal to 0.40%, preferably greater than or equal to 0.50%, preferably from 0.50 to 3.00%, preferably from 0.60 to 2.90%, preferably from 0.70 to 2.80%, preferably from 0.80 to 2.70%, preferably from 0.80 to 2.60%, preferably from 0.80 to 2.50%, preferably from 0.85 to 2.45%, preferably from 0.90 to 2.40%.

[0097] According to one variant, the mass fraction of Mn is from 0.10 to 2.40%, preferably from 0.15 to 2.40%, preferably from 0.20 to 2.40%, preferably from 0.30 to 2.40%, preferably from 0.30 to 2.00%, preferably from 0.30 to 1.50%, preferably from 0.30 to 1.00%, preferably from 0.30 to 0.80%, preferably from 0.30 to 0.60% each and / or in total.

[0098] In one embodiment, the mass fraction of Mn is greater than or equal to 0.10%, or 0.15%, or 0.20%, or 0.25%, or 0.30%, or 0.35%, or 0.40%, or 0.45%, or 0.50%, or 0.55%, or 0.60%, or 0.65%, or 0.70%, or 0.75%, or 0.80%, or 0.85%, or 0.90%. Preferably, the mass fraction of Mn is less than or equal to 3.00%, or 2.95%, or 2.90%, or 2.85%, or 2.80%, or 2.75%, or 2.70%, or 2.65%, or 2.60%, or 2.55%, or 2.50%, or 2.45%, or 2.40%, or 2.35%, or 2.30%, or 2.25%, or 2.20%, or 2.15% or 2.10%, or 2.05%, or 2.00% or 1.95%, or 1.90%, or 1.85% or 1.80%, or 1.75%, or 1.70%, or 1.65%, or 1.60%, or 1.55%, or 1.50%, or 1.45%, or 1.40%, or 1.35%, or 1.30%, or 1.25%, or 1.20%, or 1.15%, or 1.10%, or 1.15%, or 1.10%, or 1.05%, or 1.00%, or 0.95%, or 0.90%, or 0.85%, or 0.80%, or 0.75%, or 0.70 %, or 0.65%, or 0.60%.

[0099] Mn can be used to increase the mechanical strength of the alloy by solid solution and / or by dispersoids that can form during the manufacturing of the part or during post-manufacturing heat treatments. However, this element has a high solubility in aluminum and has a negative impact on conductivity. The addition of this element is of interest for alloys targeting certain applications that do not require specific performance in terms of electrical or thermal conductivity but that require high mechanical strength, such as structural parts, hydraulic blocks, etc.

[0100] Cr, V and / or Ti:

[0101] According to the present invention, at least one alloying element chosen from: Cr, V, and Ti is present in the aluminum alloy in a mass fraction greater than or equal to 0.10%, preferably greater than or equal to 0.20%, preferably greater than or equal to 0.30%, preferably greater than or equal to 0.40%, preferably greater than or equal to 0.50%, preferably from 0.50 to 3.00%, preferably from 0.60 to 2.90%, more preferably from 0.70 to 2.80%, even more preferably from 0.80 to 2.70%, even more preferably from 0.80 to 2.60%, even more preferably from 0.80 to 2.50%, even more preferably from 0.85 to 2.45%, even more preferably from 0.90 to 2.40%, each and / or in total.

[0102] According to one variant, the mass fraction of at least one alloying element chosen from: Cr, V and Ti, is from 0.10 to 2.40%, preferably from 0.15 to 2.40%, preferably from 0.20 to 2.40%, preferably from 0.30 to 2.40%, preferably from 0.30 to 2.00%, preferably from 0.30 to 1.50%, preferably from 0.30 to 1.00%, preferably from 0.30 to 0.80%, preferably from 0.30 to 0.60% each and / or in total.

[0103] In one embodiment, the mass fraction of at least one alloying element selected from: Cr, V, and Ti, is greater than or equal to 0.10%, or 0.15%, or 0.20%, or 0.25%, or 0.30%, or 0.35%, or 0.40%, or 0.45%, or 0.50%, or 0.55%, or 0.60%, or 0.65%, or 0.70%, or 0.75%, or 0.80%, or 0.85%, or 0.90%, each and / or in total.In one embodiment, the mass fraction of at least one alloying element selected from: Cr, V, and Ti is less than or equal to 3.00%, or 2.95%, or 2.90%, or 2.85%, or 2.80%, or 2.75%, or 2.70%, or 2.65%, or 2.60%, or 2.55%, or 2.50%, or 2.45%, or 2.40%, or 2.35%, or 2.30%, or 2.25%, or 2.20%, or 2.15%, or 2.10%, or 2.05%, or 2.00%, or 1.95%, or 1.90%, or 1.85%, or 1.80%, or 1.75%, or 1.70%, or 1.65%, or 1.60%, or 1.55%, or 1.50%, or 1.45%, or 1.40%, or 1.35%, or 1.30%, or 1.25%, or 1.20%, or 1.15%, or 1.10%, or 1.05%, or 1.00%, or 0.95%, or 0.90%, or 0.85%, or 0.80%, or 0.75%, or 0.70%, or 0.65%, or 0.60% each and / or in total.

[0104] These elements can increase the mechanical strength of the alloy by solid solution and / or by dispersoids that can form during the manufacturing of the part or during post-manufacturing heat treatments. However, these elements have a high solubility in aluminum and have a negative impact on conductivity. The addition of these elements is of interest for alloys targeting certain applications that do not require specific performance in terms of electrical or thermal conductivity but that require high mechanical strength, such as structural parts, hydraulic blocks, etc.

[0105] According to a preferred variant of the present invention, the aluminum alloy necessarily comprises at least one alloying element chosen from: Mn, Cr, V, and Ti, according to the mass fractions as described above, in addition to the other obligatory elements, which are Fe, Mg and at least one alloying element chosen from: Zr, Hf, Sc and Er.

[0106] According to one variant, Ti may be absent from the aluminum alloy, i.e. possibly present only as an impurity, in a mass fraction of less than 0.05%, preferably less than 0.03%.

[0107] Neither :

[0108] According to the present invention, the element Ni may be present in the aluminum alloy in a mass fraction of less than or equal to 3.00%, preferably less than or equal to 2.50%, preferably less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%. According to a variant, the element Ni may be present in the aluminum alloy in a mass fraction of greater than or equal to 500 ppm, or greater than or equal to 0.10%, or greater than or equal to 0.15%, or greater than or equal to 0.20%, or greater than or equal to 0.30%, or greater than or equal to 0.40%. In one embodiment, the mass fraction of Ni is less than or equal to 3.00%, or 2.75%, or 2.50%, or 2.25%, or 2.00%, or 1.75%, or 1.50%, or 1.25%, or 1.00%, or 0.75%, or 0.50%.In one embodiment, the mass fraction of Ni is greater than or equal to 500 ppm, or 750 ppm, or 0.10%, or 0.15%, or 0.20%, or 0.25%, or 0.30%, or 0.35%, or 0.40%.

[0109] Ni can increase the mechanical strength of the alloy by solid solution and / or by dispersoids that can form during the manufacturing of the part or during post-manufacturing heat treatments. This element has low solubility in aluminum. The addition of this element can harden the alloy without having a significant impact on the conductivity. Cu and / or Ag:

[0110] According to the present invention, at least one alloying element selected from: Cu and Ag may be present in the aluminum alloy in a mass fraction of 0.05 to 3.00%, preferably 0.10 to 2.00%, preferably 0.10 to 1.60%, preferably 0.10 to 1.50%, preferably 0.10 to 1.40%, preferably 0.10 to 1.30%, preferably 0.10 to 1.20%, preferably 0.10 to 1.10%, preferably 0.10 to 1.00%, preferably 0.10 to 0.90%, preferably 0.10 to 0.80%, preferably 0.10 to 0.70% each and / or in total. In one embodiment, the mass fraction of at least one alloying element chosen from: Cu and Ag is greater than or equal to 0.05%, or 0.06%, or 0.07%, or 0.08%, or 0.09%, or 0.10% each and / or in total.In one embodiment, the mass fraction of at least one alloying element chosen from: Cu and Ag is less than or equal to 2.00%, or 1.90%, or 1.80%, or 1.70%, or 1.60%, or 1.50%, or 1.40%, or 1.30%, or 1.20%, or 1.10%, or 1.00%, or 0.90%, or 0.80%, or 0.70% for Cu; and the mass fraction of at least one alloying element chosen from: Cu and Ag is less than or equal to 3.00%, or 2.90%, or 2.80%, or 2.70%, or 2.60%, or 2.50%, or 2.40%, or 2.30%, or 2.20%, or 2.10%, or 2.00%, or 1.90%, or 1.80%, or 1.70%, or 1.60%, or 1.50%, or 1.40%, or 1.30%, or 1.20%, or 1.10%, or 1.00%, or 0.90%, or 0.80%, or 0.70% for Ag and / or in total.

[0111] The elements Cu and Ag can increase the mechanical strength of the alloy by solid solution and / or by hardening precipitates which can form during the manufacture of the part or during post-manufacturing heat treatments.

[0112] According to one variant, Cu may be absent from the aluminum alloy, i.e. possibly present only as an impurity, in a mass fraction of less than 0.05%, preferably less than 0.03%.

[0113] Sh

[0114] According to the present invention, the element Si may be present in the aluminum alloy in a mass fraction of less than or equal to 3.00%, preferably less than or equal to 2.50%, preferably less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%; in one embodiment, the Si content is less than or equal to 0.30%, preferably less than or equal to 0.20%, preferably less than or equal to 0.15%, preferably less than or equal to 0.10%. According to a variant, the element Si may be present in the aluminum alloy in a mass fraction of greater than or equal to 500 ppm, or greater than or equal to 0.10%, or greater than or equal to 0.15%.In one embodiment, the mass fraction of Si is less than or equal to 3.00%, or 2.75%, or 2.50%, or 2.25%, or 2.00%, or 1.75%, or 1.50%, or 1.25%, or 1.00%, or 0.75%, or 0.50%, or 0.40%, or 0.30%, or 0.25%, or 0.20%, or 0.15%, or 0.10%. In one embodiment, the mass fraction of Si is greater than or equal to 500 ppm, or 600 ppm, or 700 ppm, or 800 ppm, or 900 ppm, or 0.10%, or 0.11%, or 0.12%, or 0.13%, or 0.14%, or 0.15%.

[0115] Si can increase the mechanical strength of the alloy by solid solution and / or by precipitates or dispersoids that can form during the manufacturing of the part or during post-manufacturing heat treatments. This element can have a beneficial effect by lowering the sensitivity to cracking.

[0116] The addition of Si in the presence of Zr can lead to the formation of coarse AlZrSi phases which would limit the hardening power of Zr after heat treatment.

[0117] According to one variant, the aluminum alloy comprises, preferably consists of: 0.80 to

[0118] 1.40% of at least one alloying element chosen from: Zr, Hf, Sc and Er, preferably Zr, each and / or in total; 0.20 to 1.50%, preferably 0.20 to 0.70% of Fe; 2.70 to 3.50% Mg; 0.30 to

[0119] 2.40%, or alternatively 0.20 to 0.70% of at least one alloying element chosen from: Cr, V, Ti, each and / or in total; optionally 0.30 to 2.40%, or alternatively 0.20 to 0.70% of Mn; optionally up to 0.50%, preferably up to 0.20% of Si; preferably remaining aluminum and impurities.

[0120] According to one variant, the aluminum alloy comprises, preferably consists of: 0.80 to

[0121] 1.40% of at least one alloying element chosen from: Zr, Hf, Sc and Er, preferably Zr, each and / or in total; 0.20 to 1.50%, preferably 0.20 to 0.70% of Fe; 2.70 to 3.50% Mg; 0.30 to

[0122] 2.40%, or alternatively 0.20 to 0.70% of Mn; optionally 0.30 to 2.40%, or alternatively 0.20 to 0.70% of at least one alloying element chosen from: Cr, V, Ti, each and / or in total; optionally up to 0.50%, preferably up to 0.20% of Si; preferably remaining aluminum and impurities.

[0123] Zn and / or Li:

[0124] According to the present invention, at least one alloying element chosen from: Zn and Li may be present in the aluminum alloy in a mass fraction less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30% each and / or in total. According to a variant, the elements Zn and / or Li may be present in the aluminum alloy in a mass fraction greater than or equal to 500 ppm, or greater than or equal to 0.10%, or greater than or equal to 0.20% each and / or in total. In one embodiment, the mass fraction of at least one alloying element selected from: Zn and Li is less than or equal to 2.00%, or 1.90%, or 1.80%, or 1.70%, or 1.60%, or 1.50%, or 1.40%, or 1.30%, or 1.20%, or 1.10%, or 1.00%, or 0.90%, or 0.80%, or 0.70%, or 0.60%, or 0.50%, or 0.40%, or 0.30%.In one embodiment, the mass fraction of at least one alloying element chosen from: Zn and Li is greater than or equal to 500 ppm, or 600 ppm, or 700 ppm, or 800 ppm, or 900 ppm, or 0.10%, or 0.11%, or 0.12%, or 0.13%, or 0.14%, or 0.15%, or 0.16%, or 0.17%, or 0.18%, or 0.19%, or 0.20%.

[0125] The elements Zn and Li can increase the mechanical strength of the alloy by solid solution. However, these elements are sensitive to evaporation during laser melting, which can lead to the formation of fumes and instabilities of the melt pools. Excessive addition of these elements can significantly lower the electrical conductivity. Thus, according to one embodiment, the addition of these elements is preferably avoided.

[0126] According to one variant, Zn may be absent from the aluminum alloy, i.e. possibly present only as an impurity, in a mass fraction of less than 0.05%, preferably less than 0.03%.

[0127] Co, La, Ce, mischmetal, W, Ta, Mo, Nb, Nd, Y, Tm, Lu, Yb, Sr, Ba, Sb, Bi, Ca, P, B, In and / or Sn:

[0128] According to the present invention, at least one alloying element chosen from: Co, La, Ce, mischmetal, W, Ta, Mo, Nb, Nd, Y, Tm, Lu, Yb, Sr, Ba, Sb, Bi, Ca, P, B, In and Sn, may be present in the aluminum alloy in a mass fraction less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, more preferably less than or equal to 0.30%, even more preferably less than or equal to 0.10% each, and less than or equal to 2.00%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30% in total.According to a variant, at least one alloying element chosen from: Co, La, Ce, mischmetal, W, Ta, Mo and Nb, Nd, Y, Tm, Lu, Yb, Sr, Ba, Sb, Bi, Ca, P, B, In and Sn may be present in the aluminum alloy in a mass fraction greater than 100 ppm, or greater than 300 ppm, or greater than 500 ppm each and / or in total. In one embodiment, the mass fraction of at least one alloying element selected from: Co, La, Ce, mischmetal, W, Ta, Mo, Nb, Nd, Y, Tm, Lu, Yb, Sr, Ba, Sb, Bi, Ca, P, B, In and Sn is less than or equal to 2.00%, or 1.90%, or 1.80%, or 1.70%, or 1.60%, or 1.50%, or 1.40%, or 1.30%, or 1.20%, or 1.10%, or 1.00%, or 0.90%, or 0.80%, or 0.70%, or 0.60, or 0.50%, or 0.40%, or 0.30% each and / or in total, or less than or equal to 0.20% or 0.10% each.In one embodiment, the mass fraction of at least one alloying element selected from: Co, La, Ce, mischmetal, W, Ta, Mo, Nb, Nd, Y, Tm, Lu, Yb, Sr, Ba, Sb, Bi, Ca, P, B, In and Sn is greater than or equal to 100 ppm, or 200 ppm or 300 ppm or 400 ppm or 500 ppm each and / or in total.

[0129] These elements can increase the mechanical resistance of the alloy by solid solution and / or by precipitates or dispersoids which can form during the manufacture of the part or during post-manufacturing heat treatments.

[0130] The addition of Ca may be of interest, particularly to limit the evaporation of Mg and to limit its oxidation on the surface of the liquid bath during the atomization step and during the laser fusion step on the powder bed.

[0131] According to one variant, B may be absent from the aluminum alloy, i.e. possibly present only as an impurity, in a mass fraction of less than 0.05%, preferably less than 0.03%.

[0132] The process may include, following the formation of the layers, i.e. following the formation of the final part, the application of at least one heat treatment. This treatment is also called post-manufacturing heat treatment or post-treatment. The post-manufacturing heat treatment may be or include tempering or annealing. It may also include solution treatment and quenching, although these are preferred. It may also include hot isostatic pressing.

[0133] According to a first variant, in order to favor the mechanical properties, the post-manufacturing heat treatment can be carried out:

[0134] - at a temperature T' above 400°C, in which case the duration of the post-manufacturing heat treatment is from 0.1 h to 50 h, preferably from 0.1 h to 10 h;

[0135] - or at a temperature T' between 300°C and 400°C, in which case the duration of the post-manufacturing heat treatment is between 0.1 h and 200 h.

[0136] According to a second variant, in order to favor the thermal or electrical conduction properties, the post-manufacturing heat treatment can be carried out at a temperature T' greater than or equal to 350°C or 400°C for a duration of 0.1 h to 200 h, so as to obtain optimal thermal or electrical conductivity.

[0137] According to another variant, two-stage post-manufacturing heat treatments can maximize electrical conductivity. These treatments consist of first performing a first stage at a temperature T'1 greater than 450°C for a duration of 0.1 h to 100 h, followed by a second stage at a temperature T'2 between 300°C and 450°C for a duration of 0.1 h to 200 h. According to another variant, two-stage post-manufacturing heat treatments can maximize electrical conductivity and / or hardness. These treatments consist of first performing a first stage at a temperature T'1 less than 380°C for a duration of 0.1 h to 200 h, followed by a second stage at a temperature T'2 between 380°C and 450°C for a duration of 0.1 h to 200 h.

[0138] According to another variant, three-stage post-manufacturing heat treatments can maximize electrical conductivity and / or hardness. These treatments consist of first performing a first stage at a temperature T'1 between 250°C and 450°C for a duration of 0.1 h to 200 h, followed by a second stage at a temperature T'2 above 450°C for a duration of 0.1 h to 100 h, followed by a third stage at a temperature T'3 between 250°C and 450°C for a duration of 0.1 h to 200 h.

[0139] Multi-level treatments with a number of levels greater than 3 can also be considered.

[0140] According to one embodiment, the method may comprise hot isostatic pressing (HIP). The HIP treatment may in particular improve the elongation properties and the fatigue properties. The hot isostatic pressing may be carried out before, after or instead of the post-manufacturing heat treatment. Advantageously, the hot isostatic pressing is carried out at a temperature of 250°C to 500°C and preferably 300°C to 450°C, at a pressure of 500 to 3000 bars and for a duration of 0.5 to 100 hours.

[0141] For some compositions and for some types of parts, delamination cracks may appear in areas of the part with high stress concentrations during post-manufacturing heat treatment of parts, when the latter is carried out in a standard furnace. The use of CIC treatment can prevent the appearance of these cracks.

[0142] Once the parts are loaded into a CIC furnace, applying pressure before the furnace starts heating can be advantageous to avoid delamination cracking. For example, the pressure can be increased to a value of 1500 to 3000 bar before heating starts.

[0143] According to an advantageous embodiment, the method does not include quenching following the formation of the layers, i.e. following the formation of the final part, or following the post-manufacturing heat treatment. Thus, preferably, the method does not include solution treatment steps followed by quenching.

[0144] The use of post-manufacturing heat treatment, with manufacturing carried out using an additive manufacturing process, can create stress-relieving conditions that eliminate residual stresses and precipitate hardening phases. This is also referred to as thermal stress relief. The inventors observed that it was preferable for the set temperature T' of the post-manufacturing heat treatment to be between 300°C and 500°C.

[0145] The possible heat treatment and / or hot isostatic pressing makes it possible in particular to increase the hardness or elastic limit and the electrical conductivity of the product obtained. It should be noted, however, that, generally, the higher the temperature, the more conductivity (electrical or thermal) is favored to the detriment of mechanical resistance.

[0146] According to one embodiment, in addition to the temperature T' of the post-manufacturing heat treatment, the temperature rise, initiating the post-manufacturing heat treatment, is preferably as rapid as possible. For example, during the temperature rise, the temperature rise rate AT' (usually designated by those skilled in the art as "heating rate" in °C per minute or in °C per second) is preferably greater than 5°C per minute or greater than 10°C per minute, or even preferably greater than 20°C per minute and more advantageously greater than 40°C per minute, and more advantageously greater than 100°C per minute. By temperature rise, we mean the temperature rise to which the part is subjected during the post-manufacturing heat treatment.It seems optimal that the temperature rise is instantaneous, that is to say that the manufactured part is subjected, from the start of the post-manufacturing heat treatment, to the set temperature T' of the post-manufacturing heat treatment. An instantaneous temperature rise can be obtained by placing the manufactured part in a hot furnace, already brought to the set temperature T', or by a rapid heating means such as a fluidized bed or molten salt bath. The temperature rise can also be ensured by induction heating.

[0147] For the same temperature rise outside the part, the temperature variation inside the part depends in particular on the heating medium (liquid or air or inert gas) as well as the shape of the part. In particular, the temperature in the thickness or at the surface of the part can be different. This is the reason why the temperature rise mentioned above corresponds to the temperature outside the part. The combination of a preheating temperature T, a post-manufacturing heat treatment temperature T' and a temperature rise rate AT', during the post-manufacturing heat treatment temperature rise, in the aforementioned value ranges, makes it possible to obtain parts with good resistance to thermal cracking.

[0148] According to another embodiment, suitable for structurally hardened alloys, solution treatment can be carried out followed by quenching and tempering of the formed part and / or hot isostatic pressing. In this case, hot isostatic pressing can advantageously replace solution treatment.

[0149] However, the method according to the invention is advantageous because it preferably does not require solution treatment followed by quenching. Solution treatment can have a detrimental effect on mechanical strength in certain cases by contributing to a coarsening of the dispersoids or fine intermetallic phases. Preferably, the method according to the present invention does not involve solution treatment and / or quenching following the formation of the layers, i.e. following the formation of the final part, or following the post-manufacturing heat treatment.

[0150] According to one embodiment, the method according to the present invention further optionally comprises a machining treatment, and / or a chemical, electrochemical or mechanical surface treatment, and / or a tribofinishing. These treatments can be carried out in particular to reduce roughness and / or improve corrosion resistance and / or improve resistance to the initiation of fatigue cracks.

[0151] Optionally, it is possible to carry out mechanical deformation of the part, for example after additive manufacturing and / or before heat treatment.

[0152] Although described in connection with a powder bed laser fusion type additive manufacturing method, the method can be applied to other additive manufacturing methods such as wire arc additive manufacturing (Wire plus Arc Additive Manufacturing), mentioned in connection with the prior art. Figure 2 represents such an alternative. An energy source 31, in this case a torch, forms an electric arc 32. In this device, the torch 31 is held by a welding robot 33. The part 20 to be manufactured is arranged on a support 10. In this example, the manufactured part is a wall extending along a transverse axis Z perpendicular to an XY plane defined by the support 10. Under the effect of the electric arc 32, a filler wire 35 melts to form a weld bead. The welding robot is controlled by a digital model M. It is moved so as to form different layers 20i...20 n, stacked on top of each other, forming the wall 20, each layer corresponding to a weld bead. Each layer 20i...20 n extends in the XY plane, according to a pattern defined by the digital model M.

[0153] The diameter of the filler wire is preferably less than 3 mm. It may be between 0.5 mm and 3 mm and is preferably between 0.5 mm and 2 mm, or even between 1 mm and 2 mm. It is, for example, 1.2 mm. Other methods are also conceivable, for example, and in a non-limiting manner:

[0154] - selective laser sintering;

[0155] - direct metal laser sintering;

[0156] - selective heat sintering;

[0157] - electron beam melting;

[0158] - laser melting deposition;

[0159] - direct energy deposition;

[0160] - direct metal deposition;

[0161] - direct laser deposition;

[0162] - Laser Deposition Technology;

[0163] - laser net shaping engineering;

[0164] - laser cladding technology;

[0165] - Laser Freeform Manufacturing Technology;

[0166] - laser metal deposition;

[0167] - cold spray (Cold Spray Consolidation);

[0168] - additive manufacturing by friction (Additive Friction Stir);

[0169] - spark plasma sintering or flash sintering (Field Assisted Sintering Technology or spark plasma sintering); or

[0170] - Inertia Rotary Friction Welding.

[0171] The solutions according to the present invention are particularly suitable for the cold spray process, in particular because of the low hardness of the powder, which facilitates deposition. The part can then be hardened by a hardening annealing (post-heat treatment).

[0172] The solutions according to the present invention are particularly suitable for applications in the electrical, electronic and heat exchanger fields.

[0173] The invention will be explained in more detail in the examples below, which are given for illustrative and non-limiting purposes.

[0174] Experimental examples

[0175] Example 1

[0176] A study was conducted on 5 alloys (4, 5, 6, 7 and 8). The compositions, determined by ICP (Induced Coupled Plasma) in mass % are shown in Table 1.

[0177] These five alloys were obtained in powder form for a laser powder bed fusion process using gas jet atomization (N2). The particle size of the different powders was mainly 3 pm to 120 pm, D10 was 26.8 to 28.4 pm, D50 was 41.4 to 44.3 pm and D90 was 61.1 to 64.9 pm.

[0178] [Table 1]

[0179] Using an EOSM290 type laser powder bed fusion machine (EOS supplier), cracking specimens were produced from the 5 alloys (4, 5, 6, 7 and 8) in order to study their sensitivity to cracking.

[0180] A cracking specimen, the model of which used in the examples is shown in Figure 3, has a particular geometry with two critical sites conducive to crack initiation.

[0181] The specimens were printed according to 3 different parameter sets Pl, P2 and P3. The main parameters used for each parameter set were: laser power in W; scanning speed in mm / s; vector deviation in mm; layer thickness in μm and platen temperature in °C. They are described in Table 2 below.

[0182] The EOSM290 machine used allows the build plate to be heated by heating elements up to a temperature of 200°C. The cracking specimens were printed using this machine with a plate temperature of approximately 100°C. In all cases, the specimens underwent a 2-hour post-manufacturing stress-relieving heat treatment at 300°C with a furnace at a temperature of approximately 25°C and a heating rate of approximately 5°C / min.

[0183] Once the heat treatment was carried out, the specimens were coated with a resin (10% Aradur® +90% Araldite®) and polished on the face indicated in Figure 3 (Reference 1) by different Buelher abrasive papers (from P80 to P1200) then different DP-Dur Struers polishing cloths (from 6 to 1 pm) and finally a SUPRA Presi finishing cloth.

[0184] The presence or absence of cracks was checked using an optical microscope with a magnification of X100. The results are summarized in Table 3 below. [Table 2]

[0185] The results in Table 3 above show that:

[0186] - For all sets of parameters tested, alloys 4, 7 and 8 (Iron content less than or equal to 1%) do not show any cracking.

[0187] - For all sets of parameters tested, alloy 5 (Iron content equal to 2.00% and Zirconium content equal to 1.20%) and alloy 6 (Iron content equal to 1.90% and Zirconium content equal to 0.98%) both exhibit cracking.

[0188] - For the Al-Fe-Mg-Zr alloy system studied, the present results seem to demonstrate that too high an iron content would be responsible for cracking. Indeed, samples with an iron content greater than or equal to 1.9% are sensitive to cracking. Despite the lower zirconium content of alloy 6, it also exhibits cracking. The decrease in zirconium content did not compensate for the harmful effect of the high iron content.

[0189] In a second step, the effect of iron on the mechanical properties of Al-Fe-Mg-Zr systems was studied. Cylindrical samples vertical to the build direction (Z direction) were printed from alloys 4, 7 and 8 which did not show any cracking in Table 1 above. The printing was carried out using the same EOSM290 machine. The parameter set used for printing these specimens was set P2, described above in Table 2. The purpose of these specimens is to determine the tensile mechanical properties of the 3 alloys 4, 7 and 8. The samples had a diameter of 11 mm and a height of 46 mm. A part of the samples was kept in the as-manufactured state (without additional heat treatment). A second part underwent a post-manufacturing heat treatment of 1 hour at 400°C with direct heating at 400°C.And a third part underwent a post-manufacturing heat treatment of 4 hours at 400°C with direct firing at 400°C.

[0190] The cylindrical samples were then machined to obtain tensile specimens with the following characteristics, as described in Table 4 below and Figure 4.

[0191] [Table 4]

[0192] In Table 4 above and Figure 4, 0 represents the diameter of the central part of the specimen; M the width of the two ends of the specimen; LT the total length of the specimen; R the radius of curvature between the central part and the ends of the specimen; Le the length of the central part of the specimen and F the length of the two ends of the specimen.

[0193] The specimens were then tested in tension at room temperature (25°C) according to standard NF EN ISO 6892-1 (2009-10). The results of these tensile tests are presented in Table 5 below.

[0194] [Table 5]

[0195] According to the results in Table 5 above:

[0196] Regarding the Rp0.2 measurements:

[0197] - In the as-manufactured state, i.e. without post-manufacturing heat treatment, Tl alloys 4, 7 and 8 had an RpO.2 of 221.0 MPa; 213.0 MPa and 195.2 MPa respectively.

[0198] - After post-manufacturing heat treatment at 400°C for 1 hour, alloys 4, 7 and 8 exhibited an Rp0.2 of 391.7 MPa; 365.1 MPa and 333.9 MPa respectively.

[0199] - After post-manufacturing heat treatment at 400°C for 4 hours, alloys 4, 7 and 8 exhibited an Rp0.2 of 394.3 MPa; 371.9 MPa and 340.3 MPa respectively.

[0200] - In the as-manufactured state, all the alloys therefore had a yield strength of less than 221 MPa. This low yield strength in the as-manufactured state can help limit the level of residual stresses in the as-manufactured state, which would be beneficial for the processability of the alloy by limiting its sensitivity to cracking.

[0201] - For the three alloys, the post-manufacturing heat treatment of lh at 400°C allowed an increase in Rp0.2 of respectively 170.7 MPa; 152.1 MPa and 138.8 MPa for alloys 4, 7 and 8.

[0202] - For the three alloys, the post-manufacturing heat treatment at 4h at 400°C allowed an increase in Rp0.2 of respectively 173.36 MPa; 158.90 MPa and 145.10 MPa for alloys 4, 7 and 8.

[0203] - Compared to the 1h heat treatment at 400°C, the 4h heat treatment at 400°C allowed a slight improvement in Rp0.2, with a difference ranging from +3 to +7 MPa.

[0204] These results made it possible to obtain a linear regression of Rp0.2 as a function of the mass content of Iron (%Fe) as illustrated in Figure 5. The results of these regressions are as follows:

[0205] - Rp0.2 (Raw) = 32.5 x %Fe + 190.4 (R 2 = 0.89)

[0206] - Rp0.2 (lh at 400) = 74.5 x %Fe + 319.4 (R 2 = 0.97)

[0207] - Rp0.2 (4h at 400) = 69.2 x %Fe + 327.8 (R 2 = 0.95)

[0208] These results highlighted the positive effect of the iron content, which appears to moderately improve the properties of parts described as "as manufactured", but greatly improve the mechanical properties of parts in service at 25°C after post-manufacturing heat treatment at 400°C lasting, for example, 1 hour or 4 hours.

[0209] Concerning the elongations measured during these tests:

[0210] - In the as-manufactured state, alloys 4, 7 and 8 exhibited an elongation at break of 22.9, 24.0 and 25.5% respectively.

[0211] - After post-manufacturing heat treatment at 400°C for 1 hour, alloys 4, 7 and 8 showed an elongation at break of 13.5, 14.6 and 16.2% respectively.

[0212] - After post-manufacturing heat treatment at 400°C for 4 hours, alloys 4, 7 and 8 exhibited an elongation at break of 13.9, 14.3 and 17.7% respectively. - In the as-manufactured state, all the alloys therefore exhibited an elongation at break greater than or equal to 22%.

[0213] - For the three alloys, the post-manufacturing heat treatment at 400°C for 1 hour induced a decrease in elongation of 9.42, 9.5 and 9.3% respectively for alloys 4, 7 and 8.

[0214] - For the three alloys, the post-manufacturing heat treatment at 4h at 400°C induced a decrease in elongation of 9.1, 9.9 and 7.8% respectively for alloys 4, 7 and 8.

[0215] Previous results have shown a negative effect of Fe content on elongation in the as-manufactured state and after a post-manufacturing heat treatment of 1 hour or 4 hours at 400°C.

[0216] All the results of this example showed that increasing the Fe content can improve the yield strength Rp0.2 at 25°C, after a post-manufacturing heat treatment of 1 hour at 400°C or 4 hours at 400°C. However, the Iron content must be limited to less than 1.90% to limit the sensitivity to cracking of the parts, and maintain a suitable elongation.

[0217] Example 2

[0218] A study was conducted on 10 alloys (1, 3, 13, 14, 113, 21, 22, 23, 24, 25 and 26). The compositions, determined by ICP (Induced Coupled Plasma) in mass % are indicated in Table 6 below. Alloys 1, 3, 13, 14 and 113 are counter-examples. Alloys 21 to 26 are examples according to the present invention.

[0219] These ten alloys were obtained in powder form for a laser powder bed fusion process using gas jet atomization (N2). The particle size was mainly 3 pm to 120 pm, D10 was 21.5 to 31.8 pm, D50 was 48.5 to 55.3 pm and D90 was 81.4 to 95.5 pm.

[0220] [Table 6] First, crack specimens similar to those in Example 1 were printed according to parameter set P2, described above in Table 2.

[0221] Once printed, these specimens underwent a post-manufacturing heat treatment of 2 hours at 300°C (2h300°C) with a furnace at a temperature of approximately 25°C and a temperature rise rate of approximately 5°C / min.

[0222] Once the heat treatment was carried out, the specimens were coated with a resin (10% Aradur® + 90% Araldite®) and polished on the face indicated in Figure 3 (Reference 1) by different Buelher abrasive papers (from P80 to P1200), then different DP-Dur Struers polishing cloths (from 6pm to lpm) and finally a SUPRA Presi finishing cloth.

[0223] The presence or absence of cracks was checked using an optical microscope with a magnification of X100. The results are summarized in Table 7 below.

[0224] [Table 7]

[0225] The results in Table 7 above show, for the geometry of the cracking parts tested, that alloys 1, 3, 13, 14 and 113, which do not contain magnesium, exhibit cracks. While alloys 21, 22, 23, 24, 25 and 26, which have a magnesium content of around 3.00%, do not exhibit cracks.

[0226] Cylindrical samples vertical to the build direction (Z direction) were printed from the 10 alloys (1, 3, 13, 14, 113, 21, 22, 23, 24, 25 and 26) described in Table 6 above. Printing was carried out using the same EOSM290 machine. The parameter set used for printing these specimens is the P2 set, described in Table 2 above. The purpose of these samples is to determine the mechanical characteristics in tension. These samples had a diameter of 11 mm and a height of 46 mm. A part of the samples was kept in the as-manufactured state (without additional heat treatment). A second part underwent a post-manufacturing heat treatment of 1 hour at 400°C with direct firing at 400°C. And a third part underwent a post-manufacturing heat treatment of 4 hours at 400°C with direct firing at 400°C.

[0227] The cylindrical samples were then machined to obtain tensile specimens with the characteristics as described in Table 4 above and Figure 4.

[0228] The specimens were then tested in tension at room temperature (25°C) according to standard NF EN ISO 6892-1 (2009-10). The main results are presented in Table 8 below.

[0229] [Table 8]

[0230] Regarding the Rp0.2 measurements for alloys 1, 3, 13, 14 and 113, which do not contain magnesium:

[0231] - In the as-manufactured state, alloys 1, 3, 13, 14 and 113 presented respectively an Rp0.2 of 176.2 MPa; 123.0 MPa; 139.1 MPa; 143.6 MPa and 153.4 MPa.

[0232] - After a post-manufacturing heat treatment of 1 h at 400°C, alloys 1, 3, 13, 14 and 113, presented respectively an Rp0.2 of 320.5 MPa; 281.1 MPa; 305.9 MPa; 311.2 MPa and

[0233] 313.9 MPa.

[0234] - After a post-manufacturing heat treatment of 4 hours at 400°C, alloys 1, 3, 13, 14 and 113, presented respectively an Rp0.2 of 304.5 MPa; 289.3 MPa; 305.1 MPa; 295.9 MPa and 301.3 MPa.

[0235] - For these five alloys, the post-manufacturing heat treatment at 400°C for 1 hour allowed an increase in Rp0.2 of 144.3 MPa; 158.1 MPa; 166.8 MPa; 167.6 MPa and 160.6 MPa respectively.

[0236] - For these five alloys, the post-manufacturing heat treatment at 4h at 400°C allowed an increase in Rp0.2 of respectively 128.3 MPa; 166.3 MPa; 165.9 MPa; 152.3 MPa and

[0237] 147.9 MPa.

[0238] - Compared to the 1h heat treatment at 400, the 4-hour post-manufacturing heat treatment at 400°C induced a variation of Rp0.2 between -8.15 and +16 MPa.

[0239] Regarding the Rp0.2 measurements for alloys 21, 22, 23, 24, 25 and 26, which have a magnesium content of 3.00 to 3.30%

[0240] - In the as-manufactured state, alloys 21, 22, 23, 24, 25 and 26 presented respectively an Rp0.2 of 307.9 MPa; 256.2 MPa; 262.8 MPa; 283.7 MPa; 291.6 MPa and 212 MPa.

[0241] - After post-manufacturing heat treatment at 400°C for 1 hour, alloys 21, 22, 23, 24 and 25, respectively presented an Rp0.2 of 446.1 MPa; 404.6 MPa; 417.2 MPa; 438.2 MPa and 420.2 MPa.

[0242] - After post-manufacturing heat treatment at 400°C for 4 hours, alloys 21, 22, 23, 24 and 25 and 26 exhibited respectively an Rp0.2 of 440.1 MPa; 408.3 MPa; 424.1 MPa; 454.2 MPa; 444.2 MPa and 386.2 MPa.

[0243] - For alloys 21, 22, 23, 24 and 25, the post-manufacturing heat treatment of 1 h at 400°C allowed an increase in RpO,2 of respectively 138.2 MPa; 148.4 MPa; 154.7 MPa; 154.5 MPa and 152.6 MPa.

[0244] - For alloys 21, 22, 23, 24, 25 and 26, the post-manufacturing heat treatment of 4 hours at 400°C allowed an increase in Rp0.2 of respectively 132.2 MPa; 152.1 MPa; 161.3 MPa; 170.5 MPa, 128.6 MPa and 174.2 MPa.

[0245] - Compared to the 1h heat treatment at 400°C, the 4h post-manufacturing heat treatment at 400°C induced a variation of Rp0.2 between -16.0 and +24.0 MPa for alloys 21, 22, 23, 24 and 25.

[0246] The difference in Rp0.2, comparing two by two alloys 21 and 14; 22 and 3; 23 and 13 (very similar chemical compositions except for the magnesium content), is respectively:

[0247] As manufactured, 164.3 MPa; 133.2 MPa; 123.7 MPa.

[0248] - After post-manufacturing heat treatment of 1h at 400°C, 134.9 MPa; 123.5 MPa; 111.7 MPa.

[0249] - After a post-manufacturing heat treatment of 4 hours at 400°C, of ​​144.2 MPa; 119.0 MPa; 119.0 MPa.

[0250] The results of example 2 highlight a double beneficial effect of the addition of Mg on the alloys tested:

[0251] - It improves processability by removing sensitivity to cracking;

[0252] - It improves the mechanical properties of parts in service at 25°C after post-manufacturing heat treatment, for example 1h or 4h at 400°C.

[0253] Example 3

[0254] In this example, we compared the tensile mechanical properties of alloys 4, 7, 21, 22, 23, 24, 25 and 26 in order to quantify the effect of the addition of Mn, Cr or V on the mechanical performance of Al-Fe-Mg-Zr alloys. The chemical compositions of the alloys and the techniques used to obtain them have already been explained in examples 1 and 2, as well as in Tables 1 and 6 above. Table 9 below summarizes the mechanical properties obtained. The results come from the same machined cylindrical specimens, as described in Table 4 above and Figure 4 and tested in tension at room temperature (25°C) according to standard NF EN ISO 6892-1 (2009-10). [Table 9]

[0255] The results in Table 9 above show that:

[0256] The difference in RpO.2 between alloy 4 containing no Mn (composition defined in Table 1 above) and alloy 23 containing 1% Mn (composition defined in Table 6 above) is respectively:

[0257] - 41.8 MPa in the raw state of manufacture;

[0258] - 25.9 MPa after post-manufacturing heat treatment of 1 hour at 400°C;

[0259] - 29.8 MPa after a 4-hour post-manufacturing heat treatment at 400°C. This result shows a beneficial effect of the addition of Mn on increasing the Rp0.2 of parts in service at 25°C, made from alloys of the Al-Fe-Mg-Zr system. The same conclusion can be drawn when comparing alloy 7 with alloy 21 or alloy 22 (compositions defined in Table 6 above).

[0260] The difference in RpO.2 between alloy 22 containing 1% Mn (composition defined in Table 6 above) and alloy 21 containing 2% Mn (composition defined in Table 6 above) is respectively:

[0261] - 51.7 MPa in the raw state of manufacture;

[0262] - 41.5 MPa after post-manufacturing heat treatment of 1 hour at 400°C;

[0263] - 31.8 MPa after a 4-hour post-manufacturing heat treatment at 400°C.

[0264] This result shows that increasing the mass content of Mn from 1 to 2% has a beneficial effect on increasing the Rp0.2 of parts in service at 25°C, made from alloys of the Al-Fe-Mg-Zr system.

[0265] The difference in Rp0.2 between alloy 4 containing no Cr (composition defined in Table 1 above) and alloy 24 containing 1% Cr (composition defined in Table 6 above) is respectively:

[0266] 62.7 MPa in the as-manufactured state;

[0267] - 46.5 MPa after post-manufacturing heat treatment of 1 hour at 400°C;

[0268] - 59.5 MPa after a 4-hour post-manufacturing heat treatment at 400°C.

[0269] This result shows a beneficial effect of the addition of Cr on the increase of Rp0.2 of parts in service at 25°C, from alloys of the Al-Fe-Mg-Zr system. The conclusion can be the same by comparing alloy 7 (composition defined in Table 1 above) with alloy 25 (composition defined in Table 6 above).

[0270] The difference in Rp0.2 between alloy 7 containing no V (composition defined in Table 1 above) and alloy 26 containing 0.48% V (composition defined in Table 6 above), is respectively:

[0271] -1 MPa in the raw state of manufacture;

[0272] - 14.3 MPa after a 4-hour post-manufacturing heat treatment at 400°C.

[0273] This result shows a beneficial effect of the addition of V on the increase of Rp0.2 of parts in service at 25°C, from alloys of the Al-Fe-Mg-Zr system.

Claims

CLAIMS 1. Method for manufacturing a part (20) comprising a formation of successive metal layers (20i...20 n ), superimposed on each other, each layer being formed by the deposition of a filler metal (15, 35), the filler metal being subjected to an energy input so as to melt and to constitute, by solidifying, said layer, the method being characterized in that the filler metal (15, 35) is an aluminum alloy comprising the following alloying elements (% by weight): - at least one alloying element chosen from: Zr, Hf, Sc and Er, according to a mass fraction of 0.40 to 1.60%, preferably 0.50 to 1.50%, preferably 0.60 to 1.45%, preferably 0.7 to 1.40%, preferably 0.80 to 1.40%, preferably 0.85 to 1.35% each and / or in total; - Fe, in a mass fraction of 0.03 to 1.85%, preferably 0.05 to 1.85%, preferably 0.10 to 1.85%, preferably 0.15 to 1.80%, preferably 0.20 to 1.70%, preferably 0.30 to 1.60%, preferably 0.40 to 1.50%, preferably 0.50 to 1.50%, preferably 0.60 to 1.50%, preferably 0.70 to 1.50%, preferably 0.80 to 1.50%; - Mg, in a mass fraction of 2.50 to 3.95%, preferably 2.60 to 3.90%, preferably 2.70 to 3.80%, preferably 2.70 to 3.70%, preferably 2.70 to 3.60%, preferably 2.80 to 3.60%, preferably 2.80 to 3.50%, preferably 2.90 to 3.40 0 z / o , . - at least one alloying element chosen from Cr, V and Ti, according to a mass fraction greater than or equal to 0.10%, preferably greater than or equal to 0.20%, preferably greater than or equal to 0.30%, preferably greater than or equal to 0.40%, preferably greater than or equal to 0.50%, preferably from 0.50 to 3.00%, preferably from 0.60 to 2.90%, preferably from 0.70 to 2.80%, preferably from 0.80 to 2.70%, preferably from 0.80 to 2.60%, preferably from 0.80 to 2.50%, preferably from 0.85 to 2.45%, preferably from 0.90 to 2.40%, each and / or in total; - optionally Mn, according to a mass fraction greater than or equal to 0.10%, preferably greater than or equal to 0.20%, preferably greater than or equal to 0.30%, preferably greater than or equal to 0.40%, preferably greater than or equal to 0.50%, preferably from 0.50 to 3.00%, preferably from 0.60 to 2.90%, preferably from 0.70 to 2.80%, preferably from 0.80 to 2.70%, preferably from 0.80 to 2.60%, preferably from 0.80 to 2.50%, preferably from 0.85 to 2.45%, preferably from 0.90 to 2.40%, - - optionally Ni, according to a mass fraction less than or equal to 3.00%, of preferably less than or equal to 2.50%, preferably less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%; - optionally at least one alloying element chosen from: Cu and Ag, according to a mass fraction of 0.05 to 2.00%, preferably 0.10 to 2.00%, preferably 0.10 to 1.60%, preferably 0.10 to 1.00%, preferably 0.10 to 0.70% for Cu; according to a mass fraction of 0.05 to 3.00%, preferably 0.10 to 3.00%, preferably 0.10 to 2.00%, preferably 0.10 to 1.60%, preferably 0.10 to 1.00%, preferably 0.10 to 0.70% for Ag and / or in total; - optionally If, according to a mass fraction less than or equal to 3.00%, preferably less than or equal to 2.50%, preferably less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.20%; - optionally one element from Zn and Li, according to a mass fraction less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30% each and / or in total; - optionally at least one element chosen from: Co, La, Ce, mischmetal, W, Ta, Mo and Nb, Nd, Y, Tm, Lu, Yb, Sr, Ba, Sb, Bi, Ca, P, B, In and Sn, according to a mass fraction less than or equal to 2.00%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30%, preferably less than or equal to 0.10% each, and less than or equal to 2.00%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30% in total; - impurities: < 0.05% individually, and in total < 0.15%; remainder aluminum.

2. Method according to claim 1, characterized in that the aluminum alloy necessarily comprises at least one alloying element chosen from: Mn, Cr, V, and Ti, according to the mass fractions as described in claim 1.

3. A method according to claim 1 or 2, wherein the aluminum alloy comprises, preferably consists of: 0.80 to 1.40% of at least one alloying element selected from: Zr, Hf, Sc and Er, preferably Zr, each and / or in total; 0.20 to 1.50%, preferably 0.20 to 0.70% of Fe; 2.70 to 3.50% Mg; 0.30 to 2.40%, or alternatively 0.20 to 0.7 ... at least one alloying element selected from: Cr, V, Ti, each and / or in total; optionally 0.30 to 2.40%, or alternatively 0.20 to 0.70% of Mn; optionally up to 0.50%, preferably up to 0.20% of Si; preferably remaining aluminum and impurities.

4. A method according to any preceding claim, wherein the mass fraction of aluminum is less than 97%.

5. Method according to any one of the preceding claims, comprising, following the formation of the layers (20i...20 n ), that is, following the formation of the final part, an application of a post-manufacturing heat treatment, preferably tempering or annealing.

6. Method according to any one of the preceding claims, not involving solution treatment and / or quenching following the formation of the layers, i.e. following the formation of the final part, or following the post-manufacturing heat treatment.

7. Method according to any one of the preceding claims, characterized in that it is carried out at a preheating temperature T of up to 500°C.

8. A method according to any one of the preceding claims, in which the filler metal takes the form of a powder (15), the exposure of which to a beam of light (12) or charged particles results in localized melting followed by solidification, so as to form a solid layer (20i...20 n ).

9. A method according to any one of claims 1 to 7, in which the filler metal is derived from a filler wire (35), the exposure of which to a heat source (32) results in localized melting followed by solidification, so as to form a solid layer (20i...20 n ).

10. Metal part obtained by a process which is the subject of any one of the preceding claims.

11. Powder, intended to be used as a filler material in an additive manufacturing process, characterized in that it consists of an aluminum alloy, comprising the following alloying elements (% by weight): - at least one alloying element chosen from: Zr, Hf, Sc and Er, according to a mass fraction of 0.40 to 1.60%, preferably 0.50 to 1.50%, preferably 0.60 to 1.45%, preferably 0.7 to 1.40%, preferably 0.80 to 1.40%, preferably 0.85 to 1.35% each and / or in total; - Fe, in a mass fraction of 0.03 to 1.85%, preferably 0.05 to 1.85%, preferably 0.10 to 1.85%, preferably 0.15 to 1.80%, preferably 0.20 to 1.70%, preferably 0.30 to 1.60%, preferably 0.40 to 1.50%, preferably 0.50 to 1.50%, preferably from 0.60 to 1.50%, preferably from 0.70 to 1.50%, preferably from 0.80 to 1.50%; - Mg, according to a mass fraction of 2.50 to 3.95%, preferably 2.60 to 3.90%, preferably 2.70 to 3.80%, preferably 2.70 to 3.70%, preferably 2.70 to 3.60%, preferably 2.80 to 3.60%, preferably 2.80 to 3.50%, preferably 2.90 to 3.40%; - at least one alloying element chosen from Cr, V and Ti, according to a mass fraction greater than or equal to 0.10%, preferably greater than or equal to 0.20%, preferably greater than or equal to 0.30%, preferably greater than or equal to 0.40%, preferably greater than or equal to 0.50%, preferably from 0.50 to 3.00%, preferably from 0.60 to 2.90%, preferably from 0.70 to 2.80%, preferably from 0.80 to 2.70%, preferably from 0.80 to 2.60%, preferably from 0.80 to 2.50%, preferably from 0.85 to 2.45%, preferably from 0.90 to 2.40%, each and / or in total; - optionally Mn, according to a mass fraction greater than or equal to 0.10%, preferably greater than or equal to 0.20%, preferably greater than or equal to 0.30%, preferably greater than or equal to 0.40%, preferably greater than or equal to 0.50%, preferably from 0.50 to 3.00%, preferably from 0.60 to 2.90%, preferably from 0.70 to 2.80%, preferably from 0.80 to 2.70%, preferably from 0.80 to 2.60%, preferably from 0.80 to 2.50%, preferably from 0.85 to 2.45%, preferably from 0.90 to 2.40%, - - optionally Ni, according to a mass fraction less than or equal to 3.00%, preferably less than or equal to 2.50%, preferably less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%; - optionally at least one alloying element chosen from: Cu and Ag, according to a mass fraction of 0.05 to 2.00%, preferably 0.10 to 2.00%, preferably 0.10 to 1.60%, preferably 0.10 to 1.00%, preferably 0.10 to 0.70% for Cu; according to a mass fraction of 0.05 to 3.00%, preferably 0.10 to 3.00%, preferably 0.10 to 2.00%, preferably 0.10 to 1.60%, preferably 0.10 to 1.00%, preferably 0.10 to 0.70% for Ag and / or in total; - optionally If, according to a mass fraction less than or equal to 3.00%, preferably less than or equal to 2.50%, preferably less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, of preferably less than or equal to 0.50%, preferably less than or equal to 0.20%; - optionally one element from Zn and Li, according to a mass fraction less than or equal to 2.00%, preferably less than or equal to 1.50%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30% each and / or in total; - optionally at least one element chosen from: Co, La, Ce, mischmetal, W, Ta, Mo and Nb, Nd, Y, Tm, Lu, Yb, Sr, Ba, Sb, Bi, Ca, P, B, In and Sn, according to a mass fraction less than or equal to 2.00%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30%, preferably less than or equal to 0.10% each, and less than or equal to 2.00%, preferably less than or equal to 1.00%, preferably less than or equal to 0.50%, preferably less than or equal to 0.30% in total; - impurities: < 0.05% individually, and in total < 0.15%; remainder aluminum.

12. Use of a powder according to claim 11, in a manufacturing process chosen from: electron beam melting, cold spraying, laser fusion deposition, friction additive manufacturing, plasma spark sintering or rotary friction welding, preferably cold spraying.

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