Aluminum alloy electric arc additive manufacturing process

Abstract

The invention discloses an aluminum alloy electric arc additive manufacturing process, which relates to the technical field of electric arc additive manufacturing, and comprises the following steps: S1, gradient smelting of an aluminum alloy; s2, preparing an aluminum alloy wire material; s3, carrying out model design and slicing; s4, preparing materials and equipment; s5, pretreating the substrate; s6, additive manufacturing is conducted; and S7, heat treatment. The aluminum alloy electric arc additive manufacturing process is high in effectiveness and reliability, and a manufactured component is good in mechanical property and low in porosity.

Description

Technical Field

[0001] The present invention relates to the technical field of arc additive manufacturing, and in particular to an aluminum alloy arc additive manufacturing process. Background Art

[0002] Aluminum alloys are widely used in aerospace, automobile manufacturing, shipbuilding and other fields due to their outstanding advantages such as low density, high strength, good corrosion resistance and good processing performance. However, traditional aluminum alloy manufacturing processes, such as casting, forging and machining, have many disadvantages. The casting process easily causes defects such as pores and shrinkage in aluminum alloys, resulting in reduced material properties; the forging process has high requirements for equipment, high mold costs, and it is difficult to manufacture components with complex shapes; during the machining process, a large amount of material is cut and removed, which not only causes material waste, but also increases production costs. It is in this situation that aluminum alloy arc additive manufacturing technology came into being, and its appearance has attracted widespread attention in the industry.

[0003] Arc additive manufacturing is an advanced digital manufacturing technology that uses the principle of layer-by-layer cladding, arcs generated by welding machines such as MIG welding, tungsten inert gas welding and plasma welding power as heat sources, and gradually forms metal parts from wires, surfaces and bodies according to three-dimensional digital models under the control of software programs by adding wires. Compared with laser and electron beam additive technologies, arc additive manufacturing has the advantages of high forming efficiency, low equipment cost and high material utilization, and is particularly suitable for the manufacture of large-sized aluminum alloy components. However, in the additive manufacturing process of aluminum alloys, the molten pool temperature is difficult to control accurately, which can easily lead to molten pool fluctuations, and then produce defects such as pores, cracks, and unfused parts; on the other hand, multiple thermal cycles in the arc additive manufacturing process will make the microstructure of the aluminum alloy coarse, resulting in anisotropy of material properties, which seriously limits the application of aluminum alloy arc additive manufacturing components in high-end fields.

[0004] In order to solve the above technical problems, the Chinese invention patent with the authorization announcement number CN116140755B discloses a method for arc additive manufacturing of high-strength Al-Mg alloy parts, which adopts a molten inert gas (MIG) additive manufacturing system, uses high-magnesium welding wire (Mg 5.5-6.8wt%, Zr≤0.1wt%) as wire material, adopts a single-pass swinging method to reciprocate layer-by-layer deposition, and adjusts the welding process parameters to obtain a high-strength Al-Mg aluminum alloy part with excellent forming, with a tensile strength of up to 365.0MPa and an elongation of 25.5%, which has an excellent combination of strength and plasticity. However, the mechanical properties of the parts made by the arc additive manufacturing process still need to be further improved, and the porosity needs to be further reduced.

[0005] It can be seen that it is particularly important to develop an arc additive manufacturing process for aluminum alloys with good mechanical properties and low porosity. Summary of the invention

[0006] The purpose of the present invention is to overcome the shortcomings of the prior art and provide an aluminum alloy arc additive manufacturing process with good mechanical properties and low porosity, and the process has high effectiveness and reliability.

[0007] To achieve the above object, the technical solution adopted by the present invention is: an aluminum alloy arc additive manufacturing process, comprising the following steps:

[0008] Step S1, gradient smelting of aluminum alloy: the ingredients are prepared according to the chemical composition formula of the aluminum alloy wire; pure aluminum ingots are laid on the bottom of the crucible, and other raw materials are evenly laid, and pre-melted by electromagnetic suspension. After the alloy is melted, the temperature is adjusted to 695-705°C and kept for 1-2 hours to promote uniform alloying; then, refining, slagging, modification, refinement, standing, and casting are carried out in sequence to obtain an ingot; during casting, the embryo pulling speed is dynamically adjusted according to the solidification process;

[0009] Step S2, preparation of aluminum alloy wire: subjecting the ingot obtained in step S1 to homogenization heat treatment, followed by hot extrusion, intermediate annealing treatment, and drawing to obtain a Φ1.2 mm coiled wire;

[0010] Step S3, model design and slicing: Use SolidWorks software to build a cuboid model with a size of 200 mm × 100 mm × 50 mm, use Cura slicing software to perform slicing, set the layer thickness to 0.5 mm, and generate the corresponding G code;

[0011] Step S4, material and equipment preparation: select the Φ1.2 mm coil wire prepared in step S2 as the raw material, and prepare the metal arc welding equipment and argon gas with a purity of ≥99.99%;

[0012] Step S5, substrate pretreatment: select an aluminum alloy substrate with a thickness of 10 mm, use sandpaper to grind the surface of the substrate to remove the oxide film and impurities on the surface; then, clean the surface of the substrate with acetone, and then put it into a drying oven and dry it at 120° C. for 30 minutes to ensure that the surface of the substrate is clean and dry;

[0013] Step S6, additive manufacturing: Additive manufacturing process: fix the pre-treated substrate on the workbench and start the GMAW equipment; stack the aluminum alloy wire layer by layer according to the preset G code path, and pause for 5-10 seconds after each layer is stacked;

[0014] Step S7, heat treatment: After the additive manufacturing is completed, the component is subjected to stress relief annealing and aging strengthening treatment.

[0015] Preferably, the chemical composition of the aluminum alloy wire in step S1 is as follows by mass percentage: silicon 6.5-7.5%, magnesium 0.45-0.65%, titanium 0.12-0.18%, antimony 0.02-0.06%, zinc 0.05-0.1%, copper 0.05-0.1%, manganese 0.05-0.1%, iron ≤0.1%, and the remainder is Al and other inevitable impurities.

[0016] Preferably, the titanium is added in two forms, wherein the mass added in the form of Al-Ti master alloy does not exceed 80% of the total titanium addition, and the remaining titanium is added in the form of Al-Ti-CB refiner during the refinement treatment stage.

[0017] Preferably, the refining and slagging in step S1 also includes a sampling and analysis step before the refining and slagging, and the composition of the alloy melt is adjusted according to the analysis results.

[0018] Preferably, the temperature of the refining and slagging in step S1 is controlled at 710-720° C., the refining time is 10-15 min, and after the refining is completed, the slag adhered to the inner wall of the crucible and the slag on the surface of the melt are removed.

[0019] Preferably, the modification treatment in step S1 is specifically as follows: adjusting the temperature of the melt to 710-725° C., injecting the composite modifier using a rotary spraying technique, with a rotation speed of 200-400 rpm, injecting the composite modifier mixed with argon into the melt, and enhancing the dispersion through the Coriolis effect, and the modification treatment time is 10-20 min.

[0020] Preferably, the composite modifier is a Mg-Sr composite modifier, and the addition amount is 0.02-0.05% of the total mass of the melt.

[0021] Preferably, the refinement treatment in step S1 is specifically as follows: raising the temperature to 730-745° C., using a porous manifold with a porosity of 60-80% to spray the Al-Ti-BC refiner along the direction of the melt depth, and stirring for 5-8 minutes.

[0022] Preferably, the Al-Ti-BC refiner is AlTi 5 BC.

[0023] Preferably, the standing time in step S1 is 15-20 minutes, and the slag on the surface of the melt is scraped off after standing.

[0024] Preferably, the casting temperature in step S1 is 730-740°C, the initial casting speed is 0.8-0.9 m / h, the speed is increased to 1.1-1.3 m / h after the molten pool is stabilized, and the speed is 0.6-0.7 m / h at the end of casting.

[0025] Preferably, the homogenization heat treatment in step S2 is carried out at a temperature of 455-485° C., with a holding time of 22-33 hours, followed by air cooling after exiting the furnace.

[0026] Preferably, the extrusion ratio of the hot extrusion in step S2 is (40-70):1, the extrusion speed is 2-4 mm / s, and the extrusion temperature is 420-460°C.

[0027] Preferably, the temperature of the intermediate annealing treatment in step S2 is 310-360° C., and the holding time is 1-2 h.

[0028] Preferably, the welding current of the GMAW equipment in step S6 is 180-220A, the welding voltage is 20-24V, the wire feeding speed is 6-8m / min, and the argon gas flow rate is 15-20L / min.

[0029] Preferably, the stress annealing treatment in step S7 is specifically as follows: placing the component in a heat treatment furnace, heating it to 350-400° C. at a heating rate of 5° C. / min, keeping it at that temperature for 2-3 hours, and then cooling it to room temperature in the furnace.

[0030] Preferably, the aging strengthening treatment in step S7 is specifically as follows: placing the component in a heat treatment furnace at a temperature of 460°C to 540°C for 3 to 4 hours, placing it in water for quenching treatment after the insulation is completed, and further placing the quenched component in a heat treatment furnace at a temperature of 130°C to 170°C for 9 hours to 18 hours.

[0031] Due to the application of the above technical solution, the present invention has the following beneficial effects:

[0032] (1) The aluminum alloy arc additive manufacturing process disclosed in the present invention is simple and easy to operate, has high manufacturing efficiency and finished product qualification rate, has low dependence on equipment, is easy for large-scale industrial production, and has high promotion and application value.

[0033] (2) In the aluminum alloy arc additive manufacturing process disclosed in the present invention, the chemical composition of the aluminum alloy wire is as follows in terms of mass percentage: silicon 6.5-7.5%, magnesium 0.45-0.65%, titanium 0.12-0.18%, antimony 0.02-0.06%, zinc 0.05-0.1%, copper 0.05-0.1%, manganese 0.05-0.1%, iron ≤0.1%, and the balance is Al and other unavoidable impurities. On the basis of the composition formula of ZL114A aluminum alloy, by optimizing the types and dosage ratios of alloy components, especially the ratio of silicon to magnesium, the brittleness problem of traditional ZL114A aluminum alloy is overcome, and the ductility, crack resistance and fracture toughness of additively manufactured structural parts are improved; specifically, the dosage of Si, Mg and Ti main alloying elements is optimized, the beneficial effects of Zn, Cu and Mn impurity elements on the alloy are fully utilized, and Sb high-efficiency modifier is introduced to regulate the organization, which can ensure that the manufactured components have excellent tensile properties, high yield strength and outstanding elongation. Be in traditional ZL114A aluminum alloy is not added, which avoids the generation of toxic dust under the action of electric arc to harm the health of operators, and also avoids defects such as thermal cracks in the additive process that may cause performance degradation. In ZL114A alloy without Be, high magnesium content will promote the formation of coarse Fe-containing impurity phases and increase the overall volume fraction, reducing the alloy performance. The present invention avoids the negative impact of magnesium on the alloy embrittlement effect by precisely controlling the magnesium content within the range of 0.45%-0.65%, while ensuring the molding quality of the alloy during arc additive manufacturing; the addition of Sb, in coordination with other components, can fully improve the morphology of eutectic silicon and reduce the porosity of additively manufactured structural parts; the present invention improves the strength, plasticity and elongation of additively manufactured structural parts by adding appropriate amounts of Mn, Cu and Zn elements. In the national standard of ZL114A alloy, Mn, Cu and Zn are controlled as impurity elements. By reasonably controlling the amount of these impurity elements and utilizing the beneficial effects of "impurity" elements on the performance of additively manufactured structural parts, higher comprehensive mechanical properties are obtained.

[0034] (3) The aluminum alloy arc additive manufacturing process disclosed in the present invention adds Al-Ti-CB refiner, which can effectively reduce the alloy's resistance to TiAl 3 Reliance on refinement reduces excess Ti, reduces the tendency of alloy "poisoning", and avoids coarse α-Al grains and abnormal structures. Aiming at the problems of uncontrollable oxidation and burning loss, uneven distribution of modifiers, and insufficient melt cleanliness of cast aluminum alloys manufactured by traditional smelting processes, the present invention proposes a raw material trial production method of gradient smelting + dynamic embryo drawing, which makes the active element burning rate low, the melt uniformity high, and the grain refinement obvious, thereby effectively reducing the porosity and crack sensitivity of the additive structure and improving its mechanical properties.

[0035] (4) The aluminum alloy arc additive manufacturing process disclosed in the present invention effectively reduces the generation of defects such as pores and cracks by optimizing the alloy composition and combining reasonable process parameter control, refines the microstructure of the aluminum alloy, and improves the density and quality of the components; through the reasonable selection of process parameters, the microstructure of the aluminum alloy components is made more uniform, the anisotropy of the material properties is significantly improved, and the comprehensive performance of the components is improved. The arc additive manufacturing technology itself has the characteristics of high forming efficiency and high material utilization rate. Combined with the process parameters of the present invention, it further improves production efficiency and reduces production costs.

[0036] (5) The aluminum alloy arc additive manufacturing process disclosed in the present invention performs stress relief annealing and aging strengthening treatment on the component after the additive manufacturing is completed, which can effectively eliminate the residual stress inside the component, stabilize the component size, and improve its mechanical properties. DETAILED DESCRIPTION

[0037] The following description is used to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are only examples, and those skilled in the art may think of other obvious variations.

[0038] Embodiment 1: An aluminum alloy arc additive manufacturing process comprises the following steps:

[0039] Step S1, gradient smelting of aluminum alloy: the ingredients are prepared according to the chemical composition formula of the aluminum alloy wire; pure aluminum ingots are laid on the bottom of the crucible, and other raw materials are evenly laid, and pre-melted by electromagnetic suspension. After the alloy is melted, the temperature is adjusted to 695°C and kept for 1 hour to promote uniform alloying; then, refining, slagging, modification, refinement, standing, and casting are carried out in sequence to obtain an ingot; during casting, the embryo pulling speed is dynamically adjusted according to the solidification process;

[0040] Step S2, preparation of aluminum alloy wire: subjecting the ingot obtained in step S1 to homogenization heat treatment, followed by hot extrusion, intermediate annealing treatment, and drawing to obtain a Φ1.2 mm coiled wire;

[0041] Step S3, model design and slicing: Use SolidWorks software to build a cuboid model with a size of 200 mm × 100 mm × 50 mm, use Cura slicing software to perform slicing, set the layer thickness to 0.5 mm, and generate the corresponding G code;

[0042] Step S4, material and equipment preparation: select the Φ1.2 mm coil wire prepared in step S2 as the raw material, and prepare the metal arc welding equipment and argon gas with a purity of ≥99.99%;

[0043] Step S5, substrate pretreatment: select an aluminum alloy substrate with a thickness of 10 mm, use sandpaper to grind the surface of the substrate to remove the oxide film and impurities on the surface; then, clean the surface of the substrate with acetone, and then put it into a drying oven and dry it at 120° C. for 30 minutes to ensure that the surface of the substrate is clean and dry;

[0044] Step S6, additive manufacturing: Additive manufacturing process: fix the pre-treated substrate on the workbench and start the GMAW equipment; stack the aluminum alloy wire layer by layer according to the preset G code path, and pause for 5 seconds after each layer is stacked;

[0045] Step S7, heat treatment: After the additive manufacturing is completed, the component is subjected to stress relief annealing and aging strengthening treatment.

[0046] The chemical composition of the aluminum alloy wire in step S1 is as follows by mass percentage: silicon 6.5%, magnesium 0.45%, titanium 0.12%, antimony 0.02%, zinc 0.05%, copper 0.05%, manganese 0.05%, iron ≤0.1%, and the balance is Al and other inevitable impurities; the titanium is added in two forms, of which the mass added in the form of Al-Ti master alloy does not exceed 80% of the total titanium addition, and the remaining titanium is added in the form of Al-Ti-CB refiner during the refinement treatment stage.

[0047] The refining and slagging in step S1 also includes a sampling and analysis step before the refining and slagging, and the composition of the alloy melt is adjusted according to the analysis results; the temperature control of the refining and slagging in step S1 is 710°C, the refining time is 10 minutes, and after the refining is completed, the slag adhered to the inner wall of the crucible and the slag on the surface of the melt are removed; the modification treatment in step S1 is specifically: the melt is temperature adjusted to 710°C, the composite modifier is injected by rotary blowing technology, the rotation speed is 200rpm, argon gas is used to mix the composite modifier and inject it into the melt, and the dispersion is enhanced by the Coriolis effect, and the modification treatment time is 10 minutes; the composite modifier is Mg-Sr composite modifier, and the addition amount is 0.02% of the total mass of the melt; the refinement treatment in step S1 is specifically: the temperature is raised to 730°C, and the Al-Ti-BC refiner is sprayed along the depth direction of the melt using a porous diverter with a porosity of 60%, and stirred for 5 minutes; the Al-Ti-BC refiner is AlTi 5 BC; the standing time in step S1 is 15 minutes, and the slag on the surface of the melt is removed after standing; the casting temperature in step S1 is 730°C, the initial casting speed is 0.8m / h, and the speed is increased to 1.1m / h after the melt pool stabilizes. At the end of casting, the speed is 0.6m / h.

[0048] The temperature of the homogenization heat treatment in step S2 is 455°C, the holding time is 22h, and the furnace is air-cooled; the extrusion ratio of the hot extrusion in step S2 is 50:1, the extrusion speed is 2mm / s, and the extrusion temperature is 420°C; the temperature of the intermediate annealing treatment in step S2 is 310°C, and the holding time is 1h; the welding current of the GMAW equipment in step S6 is 180A, the welding voltage is 20V, the wire feeding speed is 6m / min, and the argon gas flow rate is 15L / min; the stress annealing treatment in step S7 is specifically: placing the component in a heat treatment furnace, heating to 350°C at a heating rate of 5°C / min, holding for 2h, and then cooling to room temperature with the furnace; the aging strengthening treatment in step S7 is specifically: placing the component in a heat treatment furnace at a temperature of 460°C, holding for 3h, placing it in water for quenching after the holding is completed, and continuing to place the quenched component in a heat treatment furnace at a temperature of 130°C for 9h.

[0049] Embodiment 2: An aluminum alloy arc additive manufacturing process comprises the following steps:

[0050] Step S1, gradient smelting of aluminum alloy: the ingredients are prepared according to the chemical composition formula of the aluminum alloy wire; pure aluminum ingots are laid on the bottom of the crucible, and other raw materials are evenly laid, and pre-melted by electromagnetic suspension. After the alloy is melted, the temperature is adjusted to 698°C and kept warm for 1.2 hours to promote uniform alloying; then, refining, slagging, modification, refinement, standing, and casting are carried out in sequence to obtain an ingot; during casting, the embryo pulling speed is dynamically adjusted according to the solidification process;

[0051] Step S2, preparation of aluminum alloy wire: subjecting the ingot obtained in step S1 to homogenization heat treatment, followed by hot extrusion, intermediate annealing treatment, and drawing to obtain a Φ1.2 mm coiled wire;

[0052] Step S3, model design and slicing: Use SolidWorks software to build a cuboid model with a size of 200 mm × 100 mm × 50 mm, use Cura slicing software to perform slicing, set the layer thickness to 0.5 mm, and generate the corresponding G code;

[0053] Step S4, material and equipment preparation: select the Φ1.2 mm coil wire prepared in step S2 as the raw material, and prepare the metal arc welding equipment and argon gas with a purity of ≥99.99%;

[0054] Step S5, substrate pretreatment: select an aluminum alloy substrate with a thickness of 10 mm, use sandpaper to grind the surface of the substrate to remove the oxide film and impurities on the surface; then, clean the surface of the substrate with acetone, and then put it into a drying oven and dry it at 120° C. for 30 minutes to ensure that the surface of the substrate is clean and dry;

[0055] Step S6, additive manufacturing: additive manufacturing process: fix the pre-treated substrate on the workbench and start the GMAW equipment; stack the aluminum alloy wire layer by layer according to the preset G code path, and pause for 6 seconds after each layer is stacked;

[0056] Step S7, heat treatment: After the additive manufacturing is completed, the component is subjected to stress relief annealing and aging strengthening treatment.

[0057] The chemical composition of the aluminum alloy wire in step S1 is as follows by mass percentage: silicon 6.7%, magnesium 0.5%, titanium 0.14%, antimony 0.03%, zinc 0.06%, copper 0.07%, manganese 0.06%, iron ≤0.1%, and the remainder is Al and other inevitable impurities.

[0058] The titanium is added in two forms, wherein the mass added in the form of Al-Ti master alloy does not exceed 80% of the total titanium addition, and the remaining titanium is added in the form of Al-Ti-CB refiner during the refinement treatment stage; before the refining and slagging in step S1, a sampling and analysis step is also included, and the composition of the alloy melt is adjusted according to the analysis result; the temperature control of the refining and slagging in step S1 is 713°C, the refining time is 12 minutes, and after the refining is completed, the slag adhered to the inner wall of the crucible and the slag on the surface of the melt are removed.

[0059] The modification treatment in step S1 is specifically as follows: adjusting the temperature of the melt to 715°C, injecting a composite modifier using a rotary injection technique, the rotation speed is 250rpm, using argon gas mixed with the composite modifier to inject into the melt, and strengthening the dispersion through the Coriolis effect, and the modification treatment time is 12min; the composite modifier is a Mg-Sr composite modifier, and the addition amount is 0.03% of the total mass of the melt; the refinement treatment in step S1 is specifically as follows: raising the temperature to 735°C, using a porous diverter with a porosity of 65% to spray the Al-Ti-BC refiner along the depth direction of the melt, and stirring for 6min; the Al-Ti-BC refiner is AlTi 5 BC.

[0060] The standing time described in step S1 is 16 minutes, and the slag on the surface of the melt is scraped off after standing; the casting temperature described in step S1 is 733°C, the initial casting speed is 0.83m / h, the speed is increased to 1.15m / h after the molten pool is stable, and the speed is 0.63m / h at the end of casting; the temperature of the homogenization heat treatment described in step S2 is 465°C, the holding time is 25h, and the furnace is air-cooled; the extrusion ratio of the hot extrusion described in step S2 is 50:1, the extrusion speed is 2.5mm / s, and the extrusion temperature is 435°C; the temperature of the intermediate annealing treatment described in step S2 is 330°C, and the holding time is 1.3h.

[0061] The welding current of the GMAW equipment in step S6 is 190A, the welding voltage is 21V, the wire feeding speed is 6.5m / min, and the argon gas flow rate is 17L / min; the stress annealing treatment in step S7 is specifically: placing the component in a heat treatment furnace, heating it to 370°C at a heating rate of 5°C / min, keeping it warm for 2.3h, and then cooling it to room temperature with the furnace; the aging strengthening treatment in step S7 is specifically: placing the component in a heat treatment furnace at a temperature of 480°C, keeping it warm for 3.3h, and after the insulation is completed, placing it in water for quenching treatment, and continuing to place the quenched component in a heat treatment furnace at a temperature of 145°C for 11h.

[0062] Embodiment 3: An aluminum alloy arc additive manufacturing process comprises the following steps:

[0063] Step S1, gradient smelting of aluminum alloy: the ingredients are prepared according to the chemical composition formula of the aluminum alloy wire; pure aluminum ingots are laid on the bottom of the crucible, and other raw materials are evenly laid, and pre-melted by electromagnetic suspension. After the alloy is melted, the temperature is adjusted to 700°C and kept for 1.5 hours to promote uniform alloying; then, refining, slagging, modification, refinement, standing, and casting are carried out in sequence to obtain an ingot; during casting, the embryo pulling speed is dynamically adjusted according to the solidification process;

[0064] Step S2, preparation of aluminum alloy wire: subjecting the ingot obtained in step S1 to homogenization heat treatment, followed by hot extrusion, intermediate annealing treatment, and drawing to obtain a Φ1.2 mm coiled wire;

[0065] Step S3, model design and slicing: Use SolidWorks software to build a cuboid model with a size of 200 mm × 100 mm × 50 mm, use Cura slicing software to perform slicing, set the layer thickness to 0.5 mm, and generate the corresponding G code;

[0066] Step S4, material and equipment preparation: select the Φ1.2 mm coil wire prepared in step S2 as the raw material, and prepare the metal arc welding equipment and argon gas with a purity of ≥99.99%;

[0067] Step S5, substrate pretreatment: select an aluminum alloy substrate with a thickness of 10 mm, use sandpaper to grind the surface of the substrate to remove the oxide film and impurities on the surface; then, clean the surface of the substrate with acetone, and then put it into a drying oven and dry it at 120° C. for 30 minutes to ensure that the surface of the substrate is clean and dry;

[0068] Step S6, additive manufacturing: additive manufacturing process: fix the pre-treated substrate on the workbench and start the GMAW equipment; according to the preset G code path, stack the aluminum alloy wire layer by layer, and pause for 7.5 seconds after each layer is stacked;

[0069] Step S7, heat treatment: After the additive manufacturing is completed, the component is subjected to stress relief annealing and aging strengthening treatment.

[0070] Preferably, the chemical composition of the aluminum alloy wire in step S1 is as follows in mass percentage: silicon 7%, magnesium 0.55%, titanium 0.15%, antimony 0.04%, zinc 0.07%, copper 0.07%, manganese 0.08%, iron ≤0.1%, and the remainder is Al and other inevitable impurities; the titanium is added in two forms, of which the mass added in the form of Al-Ti master alloy does not exceed 80% of the total titanium addition, and the remaining titanium is added in the form of Al-Ti-CB refiner during the refinement treatment stage.

[0071] The refining and slagging in step S1 also includes a sampling and analysis step before the refining and slagging, and the composition of the alloy melt is adjusted according to the analysis results; the temperature control of the refining and slagging in step S1 is 715°C, the refining time is 13min, and the slag adhered to the inner wall of the crucible and the slag on the surface of the melt are removed after the refining is completed; the modification treatment in step S1 is specifically: the melt is temperature adjusted to 718°C, the composite modifier is injected by rotary blowing technology, the rotation speed is 300rpm, argon gas is used to mix the composite modifier and inject it into the melt, and the dispersion is enhanced by the Coriolis effect, and the modification treatment time is 15min; the composite modifier is Mg-Sr composite modifier, and the addition amount is 0.035% of the total mass of the melt; the refinement treatment in step S1 is specifically: the temperature is raised to 738°C, and the Al-Ti-BC refiner is sprayed along the depth direction of the melt using a porous diverter with a porosity of 70%, and stirred for 6.5min; the Al-Ti-BC refiner is AlTi 5 BC; the standing time in step S1 is 17 minutes, and the slag on the surface of the melt is removed after standing; the casting temperature in step S1 is 735°C, the initial casting speed is 0.85m / h, and the speed is increased to 1.2m / h after the molten pool stabilizes. At the end of casting, the speed is 0.65m / h.

[0072] The temperature of the homogenization heat treatment in step S2 is 470°C, the holding time is 28h, and the furnace is air-cooled; the extrusion ratio of the hot extrusion in step S2 is 50:1, the extrusion speed is 3mm / s, and the extrusion temperature is 440°C; the temperature of the intermediate annealing treatment in step S2 is 340°C, and the holding time is 1.5h; the welding current of the GMAW equipment in step S6 is 200A, the welding voltage is 22V, the wire feeding speed is 7m / min, and the argon gas flow rate is 18L / m in; the stress annealing treatment described in step S7 is specifically as follows: placing the component in a heat treatment furnace, heating it to 380°C at a heating rate of 5°C / min, keeping it warm for 2.5 hours, and then cooling it to room temperature with the furnace; the aging strengthening treatment described in step S7 is specifically as follows: placing the component in a heat treatment furnace at a temperature of 500°C, keeping it warm for 3.5 hours, placing it in water for quenching treatment after the insulation is completed, and continuing to place the quenched component in a heat treatment furnace at a temperature of 150°C for 12 hours.

[0073] Embodiment 4: An aluminum alloy arc additive manufacturing process comprises the following steps:

[0074] Step S1, gradient smelting of aluminum alloy: the ingredients are prepared according to the chemical composition formula of the aluminum alloy wire; pure aluminum ingots are laid on the bottom of the crucible, and other raw materials are evenly laid, and pre-melted by electromagnetic suspension. After the alloy is melted, the temperature is adjusted to 703°C and kept for 1.8 hours to promote uniform alloying; then, refining, slagging, modification, refinement, standing, and casting are carried out in sequence to obtain an ingot; during casting, the embryo pulling speed is dynamically adjusted according to the solidification process;

[0075] Step S2, preparation of aluminum alloy wire: subjecting the ingot obtained in step S1 to homogenization heat treatment, followed by hot extrusion, intermediate annealing treatment, and drawing to obtain a Φ1.2 mm coiled wire;

[0076] Step S3, model design and slicing: Use SolidWorks software to build a cuboid model with a size of 200 mm × 100 mm × 50 mm, use Cura slicing software to perform slicing, set the layer thickness to 0.5 mm, and generate the corresponding G code;

[0077] Step S4, material and equipment preparation: select the Φ1.2 mm coil wire prepared in step S2 as the raw material, and prepare the metal arc welding equipment and argon gas with a purity of ≥99.99%;

[0078] Step S5, substrate pretreatment: select an aluminum alloy substrate with a thickness of 10 mm, use sandpaper to grind the surface of the substrate to remove the oxide film and impurities on the surface; then, clean the surface of the substrate with acetone, and then put it into a drying oven and dry it at 120° C. for 30 minutes to ensure that the surface of the substrate is clean and dry;

[0079] Step S6, additive manufacturing: additive manufacturing process: fix the pre-treated substrate on the workbench and start the GMAW equipment; stack the aluminum alloy wire layer by layer according to the preset G code path, and pause for 9 seconds after each layer is stacked;

[0080] Step S7, heat treatment: After the additive manufacturing is completed, the component is subjected to stress relief annealing and aging strengthening treatment.

[0081] The chemical composition of the aluminum alloy wire in step S1 is as follows by mass percentage: silicon 7.3%, magnesium 0.6%, titanium 0.17%, antimony 0.05%, zinc 0.09%, copper 0.09%, manganese 0.09%, iron ≤0.1%, and the balance is Al and other inevitable impurities; the titanium is added in two forms, wherein the mass added in the form of Al-Ti master alloy does not exceed 80% of the total titanium addition, and the remaining titanium is added in the form of Al-Ti-CB refiner during the refinement treatment stage; before the refining and slagging in step S1, a sampling and analysis step is also included, and the composition of the alloy melt is adjusted according to the analysis results; the temperature control of the refining and slagging in step S1 is 718°C, and the refining time is 14min After the refining is completed, the slag adhered to the inner wall of the crucible and the slag on the surface of the melt are removed; the modification treatment in step S1 is specifically as follows: the melt is temperature adjusted to 723°C, a composite modifier is injected by rotary blowing technology, the rotation speed is 350rpm, argon is used to mix the composite modifier and inject it into the melt, and the dispersion is enhanced by the Coriolis effect, and the modification treatment time is 18min; the composite modifier is Mg-Sr composite modifier, and the addition amount is 0.04% of the total mass of the melt; the refinement treatment in step S1 is specifically as follows: the temperature is raised to 743°C, and a porous diverter with a porosity of 75% is used to spray the Al-Ti-BC refiner along the depth direction of the melt, and stirred for 7.5min; the Al-Ti-BC refiner is AlTi 5 BC; the standing time in step S1 is 19 minutes, and the slag on the surface of the melt is removed after standing; the casting temperature in step S1 is 738°C, the initial casting speed is 0.88m / h, and the speed is increased to 1.25m / h after the molten pool stabilizes. At the end of casting, the speed is 0.68m / h.

[0082] The temperature of the homogenization heat treatment in step S2 is 480°C, the holding time is 32h, and the furnace is air-cooled; the extrusion ratio of the hot extrusion in step S2 is 50:1, the extrusion speed is 3.5mm / s, and the extrusion temperature is 450°C; the temperature of the intermediate annealing treatment in step S2 is 350°C, and the holding time is 1.8h; the welding current of the GMAW equipment in step S6 is 210A, the welding voltage is 23V, the wire feeding speed is 7.5m / min, and the argon gas flow rate is 19L / min; the stress annealing treatment described in step S7 is specifically: placing the component in a heat treatment furnace, heating it to 390°C at a heating rate of 5°C / min, keeping it warm for 2.8h, and then cooling it to room temperature with the furnace; the aging strengthening treatment described in step S7 is specifically: placing the component in a heat treatment furnace at a temperature of 530°C, keeping it warm for 3.8h, placing it in water for quenching treatment after the insulation is completed, and continuing to place the quenched component in a heat treatment furnace at a temperature of 165°C for 16h.

[0083] Embodiment 5: An aluminum alloy arc additive manufacturing process comprises the following steps:

[0084] Step S1, gradient smelting of aluminum alloy: the ingredients are prepared according to the chemical composition formula of the aluminum alloy wire; pure aluminum ingots are laid on the bottom of the crucible, and other raw materials are evenly laid, and pre-melted by electromagnetic suspension. After the alloy is melted, the temperature is adjusted to 705°C and kept for 2 hours to promote uniform alloying; then, refining, slagging, modification, refinement, standing, and casting are carried out in sequence to obtain an ingot; during casting, the embryo pulling speed is dynamically adjusted according to the solidification process;

[0085] Step S2, preparation of aluminum alloy wire: subjecting the ingot obtained in step S1 to homogenization heat treatment, followed by hot extrusion, intermediate annealing treatment, and drawing to obtain a Φ1.2 mm coiled wire;

[0086] Step S3, model design and slicing: Use SolidWorks software to build a cuboid model with a size of 200 mm × 100 mm × 50 mm, use Cura slicing software to perform slicing, set the layer thickness to 0.5 mm, and generate the corresponding G code;

[0087] Step S4, material and equipment preparation: select the Φ1.2 mm coil wire prepared in step S2 as the raw material, and prepare the metal arc welding equipment and argon gas with a purity of ≥99.99%;

[0088] Step S5, substrate pretreatment: select an aluminum alloy substrate with a thickness of 10 mm, use sandpaper to grind the surface of the substrate to remove the oxide film and impurities on the surface; then, clean the surface of the substrate with acetone, and then put it into a drying oven and dry it at 120° C. for 30 minutes to ensure that the surface of the substrate is clean and dry;

[0089] Step S6, additive manufacturing: additive manufacturing process: fix the pre-treated substrate on the workbench and start the GMAW equipment; stack the aluminum alloy wire layer by layer according to the preset G code path, and pause for 10 seconds after each layer is stacked;

[0090] Step S7, heat treatment: After the additive manufacturing is completed, the component is subjected to stress relief annealing and aging strengthening treatment.

[0091] The chemical composition of the aluminum alloy wire in step S1 is as follows in mass percentage: silicon 7.5%, magnesium 0.65%, titanium 0.18%, antimony 0.06%, zinc 0.1%, copper 0.1%, manganese 0.1%, iron ≤0.1%, and the balance is Al and other inevitable impurities; the titanium is added in two forms, wherein the mass added in the form of Al-Ti master alloy does not exceed 80% of the total titanium addition, and the remaining titanium is added in the form of Al-Ti-CB refiner during the refinement treatment stage; before the refining and slagging in step S1, a sampling and analysis step is also included, and the composition of the alloy melt is adjusted according to the analysis results; the temperature control of the refining and slagging in step S1 is 720°C, and the refining time is 15min After refining, the slag adhered to the inner wall of the crucible and the slag on the surface of the melt are removed; the modification treatment in step S1 is specifically as follows: the melt is temperature adjusted to 725°C, a composite modifier is injected by rotary blowing technology, the rotation speed is 400rpm, argon gas is used to mix the composite modifier and inject it into the melt, and the dispersion is enhanced by the Coriolis effect, and the modification treatment time is 20min; the composite modifier is Mg-Sr composite modifier, and the addition amount is 0.05% of the total mass of the melt; the refinement treatment in step S1 is specifically as follows: the temperature is raised to 745°C, and a porous diverter with a porosity of 80% is used to spray the Al-Ti-BC refiner along the depth direction of the melt, and stirred for 8min; the Al-Ti-BC refiner is AlTi 5 BC; the standing time in step S1 is 20 minutes, and the slag on the surface of the melt is removed after standing; the casting temperature in step S1 is 740°C, the initial casting speed is 0.9m / h, and the speed is increased to 1.3m / h after the molten pool stabilizes. At the end of casting, the speed is 0.7m / h.

[0092] The temperature of the homogenization heat treatment in step S2 is 485°C, the holding time is 33h, and the furnace is air-cooled; the extrusion ratio of the hot extrusion in step S2 is 50:1, the extrusion speed is 4mm / s, and the extrusion temperature is 460°C; the temperature of the intermediate annealing treatment in step S2 is 360°C, and the holding time is 2h; the welding current of the GMAW equipment in step S6 is 220A, the welding voltage is 24V, the wire feeding speed is 8m / min, and the argon gas flow rate is 20L / min; the stress annealing treatment in step S7 is specifically: placing the component in a heat treatment furnace, heating to 400°C at a heating rate of 5°C / min, holding for 3h, and then cooling to room temperature with the furnace; the aging strengthening treatment in step S7 is specifically: placing the component in a heat treatment furnace at a temperature of 540°C, holding for 4h, placing it in water for quenching after the holding is completed, and continuing to place the quenched component in a heat treatment furnace at a temperature of 170°C for 18h.

[0093] Comparative Example 1: An aluminum alloy arc additive manufacturing process is basically the same as Example 1, except that no antimony is added and there is no refinement step.

[0094] Comparative Example 2: An aluminum alloy arc additive manufacturing process is basically the same as Example 1, except that there is no modification step, and the billet pulling speed is not dynamically adjusted according to the solidification process during casting, but is fixed at 0.8m / h.

[0095] In order to further illustrate the beneficial technical effects of the aluminum alloy arc additive manufacturing process involved in each embodiment of the present invention, the components made by the aluminum alloy arc additive manufacturing process involved in Examples 1-5 and Comparative Examples 1-2 were subjected to relevant performance tests. The test results are shown in Table 1. The test method is as follows: According to GB / T 39254-2020 "General Rules for Mechanical Performance Evaluation of Additively Manufactured Metal Parts", standard tensile specimens were processed, and with reference to GB / T 228.1-2021 "Metallic Material Tensile Test Part 1: Room Temperature Test Method", tensile tests were carried out on a universal material testing machine to determine the mechanical properties of the components. Image ProPlus 6.0 software was used to assist in the microscopic analysis of the porosity of the components, and the average porosity and average pore diameter were statistically analyzed.

[0096]

[0097] As can be seen from Table 1, the components made by the aluminum alloy arc additive manufacturing process involved in the embodiment of the present invention have better mechanical properties and lower porosity and pore size than the comparative example products; the combination of antimony, refinement treatment steps, modification treatment steps, and dynamically adjusting the billet pulling speed according to the solidification process during casting is beneficial to improving the above properties. Through the optimization of the above manufacturing process and component formula, the performance of the traditional ZL114A aluminum alloy is significantly improved, and its application range is broadened.

[0098] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with this technology to understand the contents of the present invention and implement them accordingly. They cannot be used to limit the protection scope of the present invention. All equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. An aluminum alloy arc additive manufacturing process, characterized in that: The steps include: Step S1, preparing materials according to the chemical composition formula of aluminum alloy wire; using pure aluminum ingot to lay the bottom of the crucible, and evenly laying other raw materials, pre-melting by electromagnetic suspension, after the alloy is melted, adjusting the temperature to 695-705℃ and keeping it for 1-2h to promote uniform alloying; then refining, slagging, modification, refinement, standing, and casting are carried out in sequence to obtain an ingot; during casting, the pulling speed is dynamically adjusted according to the solidification process; Step S2, subjecting the ingot obtained in step S1 to homogenization heat treatment, followed by hot extrusion, intermediate annealing treatment, and drawing, to obtain a Φ1.2 mm specification coiled wire; Step S3, using SolidWorks software to build a cuboid model with a size of 200 mm × 100 mm × 50 mm, using Cura slicing software to perform slicing, setting the layer thickness to 0.5 mm, and generating the corresponding G code; Step S4, selecting the Φ1.2 mm coil wire prepared in step S2 as a raw material, and preparing metal arc welding equipment and argon gas with a purity of ≥99.99%; Step S5, selecting an aluminum alloy substrate with a thickness of 10 mm, and using sandpaper to grind the surface of the substrate to remove the oxide film and impurities on the surface; then, cleaning the surface of the substrate with acetone, and then putting it into a drying oven, and drying it at 120° C. for 30 minutes to ensure that the surface of the substrate is clean and dry; Step S6, additive manufacturing process: fix the pre-treated substrate on the workbench and start the GMAW equipment; stack the aluminum alloy wire layer by layer according to the preset G code path, and pause for 5-10 seconds after each layer is stacked; Step S7: After the additive manufacturing is completed, the component is subjected to stress relief annealing and aging strengthening treatment.

2. The aluminum alloy arc additive manufacturing process according to claim 1, characterized in that: The chemical composition of the aluminum alloy wire in step S1 is as follows by mass percentage: silicon 6.5-7.5%, magnesium 0.45-0.65%, titanium 0.12-0.18%, antimony 0.02-0.06%, zinc 0.05-0.1%, copper 0.05-0.1%, manganese 0.05-0.1%, iron ≤0.1%, and the balance is Al and other inevitable impurities; the titanium is added in two forms, of which the mass added in the form of Al-Ti master alloy does not exceed 80% of the total titanium addition, and the remaining titanium is added in the form of Al-Ti-CB refiner during the refinement treatment stage.

3. The aluminum alloy arc additive manufacturing process according to claim 1, characterized in that: The refining and slagging in step S1 also includes a sampling and analysis step before the refining and slagging, and the composition of the alloy melt is adjusted according to the analysis results; the temperature of the refining and slagging in step S1 is controlled at 710-720°C, the refining time is 10-15min, and after the refining is completed, the slag adhered to the inner wall of the crucible and the slag on the surface of the melt are removed.

4. The aluminum alloy arc additive manufacturing process according to claim 1, characterized in that: The modification treatment in step S1 is specifically as follows: adjusting the temperature of the melt to 710-725° C., injecting a composite modifier using a rotary spraying technique, the rotation speed is 200-400 rpm, using argon gas mixed with the composite modifier to inject into the melt, and strengthening the dispersion through the Coriolis effect, and the modification treatment time is 10-20 minutes; the composite modifier is a Mg-Sr composite modifier, and the addition amount is 0.02-0.05% of the total mass of the melt.

5. The aluminum alloy arc additive manufacturing process according to claim 1, characterized in that: The refinement treatment in step S1 is specifically as follows: raising the temperature to 730-745°C, using a porous manifold with a porosity of 60-80% to spray the Al-Ti-BC refiner along the direction of the melt depth, and stirring for 5-8 minutes; the Al-Ti-BC refiner is AlTi5BC.

6. The aluminum alloy arc additive manufacturing process according to claim 1, characterized in that: The standing time in step S1 is 15-20 minutes, and the slag on the surface of the melt is scraped off after standing; the casting temperature in step S1 is 730-740°C, the initial casting speed is 0.8-0.9m / h, and the speed is increased to 1.1-1.3m / h after the molten pool is stable. At the end of casting, the speed is 0.6-0.7m / h.

7. The aluminum alloy arc additive manufacturing process according to claim 1, characterized in that: The temperature of the homogenization heat treatment in step S2 is 455-485°C, the holding time is 22-33h, and the furnace is air-cooled; the extrusion ratio of the hot extrusion in step S2 is (40-70):1, the extrusion speed is 2-4mm / s, and the extrusion temperature is 420-460°C; the temperature of the intermediate annealing treatment in step S2 is 310-360°C, and the holding time is 1-2h.

8. The aluminum alloy arc additive manufacturing process according to claim 1, characterized in that: The welding current of the GMAW equipment in step S6 is 180-220A, the welding voltage is 20-24V, the wire feeding speed is 6-8m / min, and the argon gas flow rate is 15-20L / min.

9. The aluminum alloy arc additive manufacturing process according to claim 1, characterized in that: The stress annealing treatment in step S7 is specifically as follows: placing the component in a heat treatment furnace, heating it to 350-400° C. at a heating rate of 5° C. / min, keeping it at that temperature for 2-3 hours, and then cooling it to room temperature in the furnace.

10. The aluminum alloy arc additive manufacturing process according to claim 1, characterized in that: The aging strengthening treatment in step S7 is specifically as follows: placing the component in a heat treatment furnace at a temperature of 460°C to 540°C for 3 to 4 hours, placing it in water for quenching after the insulation is completed, and further placing the quenched component in a heat treatment furnace at a temperature of 130°C to 170°C for 9 hours to 18 hours.

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