Heat-treatment-free die-casting aluminum alloy material, preparation method and die casting manufacturing method

Abstract

The invention provides a heat treatment-free die-casting aluminum alloy material, a preparation method and a die casting manufacturing method, and belongs to the technical field of aluminum alloy materials and casting, the die-casting aluminum alloy material comprises the following components in percentage by mass: 0.02 to 3.5 percent of Cu, 0.02 to 3.5 percent of Zn, 0.5 to 4.5 percent of Si, 1.0 to 9.0 percent of Mg, less than or equal to 0.3 percent of Fe, 0.001 to 0.06 percent of In, 0.001 to 0.06 percent of Ga, 0.04 to 0.7 percent of Mn, 0.005 to 0.35 percent of V, 0.005 to 0.35 percent of Mo, 0.02 to 0.4 percent of Zr, 0.004 to 0.07 percent of B, 0.04 to 0.7 percent of Cr, 0.02 to 0.4 percent of Ti, 0.0002 to 0.003 percent of Be, 0.02 to 0.5 percent of Sc, 0.02 to 0.5 percent of Gd, 0.02 to 0.5 percent of Dy, less than or equal the total amount of impurity elements is less than or equal to 0.20%. A component manufactured through remelting and high-pressure die casting of the die-casting aluminum alloy material has the yield strength not lower than 285 MPa, the tensile strength not lower than 340 MPa and the percentage elongation after fracture not lower than 7.0%, has excellent die-casting formability and can meet the requirement of high-pressure die-casting production of an integrated frame for a new material.

Description

Technical Field

[0001] The present invention relates to the field of aluminum alloy materials and casting technology, and in particular to a heat treatment-free die-casting aluminum alloy material and a preparation method, and a die-casting manufacturing method. Background Art

[0002] There are many parts in the car with complex shapes and large variations in wall thickness. Although high-pressure die casting can obtain aluminum alloy workpieces close to the final shape and size, the existing die-cast aluminum alloy materials used for high-pressure die casting are not strong in the casting state, and they all need to go through a series of heat treatments to improve their comprehensive performance to meet the performance requirements of the parts. Usually, aluminum alloy parts need to undergo heat treatment processes such as solution treatment and artificial aging. Among them, solution treatment is a process in which the workpiece is heated to a high temperature in a high-temperature heating furnace and kept warm for a certain period of time, and then taken out and water-cooled to room temperature; then artificial aging treatment is obtained. The complex-shaped aluminum alloy die-castings formed by high-pressure die casting are very likely to produce strong deformation after solution treatment, and the shape and size need to be corrected. The subsequent artificial aging time is long, and the die-cast aluminum alloy workpieces that have been heat-treated have a high scrap rate, a long production cycle, and high costs.

[0003] The die-cast aluminum alloy materials currently used are Al-Si aluminum alloys, and the commonly used grades are ADC12, A380, 46500, etc. This type of die-cast aluminum alloy usually has a certain strength in the die-cast state without heat treatment, but generally has poor plasticity, resulting in poor dynamic mechanical properties, low impact toughness and fracture toughness, and it is difficult to meet the development requirements of the automotive industry for the comprehensive performance of heat-free aluminum alloy die-casting parts. Therefore, there is an urgent need for a die-cast aluminum alloy material that has high strength and toughness without heat treatment and good die-casting formability to meet the development needs of integrated forming of complex-shaped automotive parts. Summary of the invention

[0004] The purpose of the present invention is to provide a heat-treatment-free die-casting aluminum alloy material and preparation method, and a die-casting manufacturing method, so as to solve the technical problem of poor plasticity of existing heat-treatment-free aluminum alloy die-castings. The present invention reasonably optimizes the alloying elements of the aluminum alloy and adds an appropriate amount of rare earth elements for micro-alloying, so that higher strength and plasticity can be obtained without heat treatment, and it is suitable for the production of complex automotive parts.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is as follows:

[0006] A heat treatment-free die-casting aluminum alloy material, comprising the following components in mass percentage: Cu: 0.02-3.5%, Zn: 0.02-3.5%, Si: 0.5-4.5%, Mg: 1.0-9.0%, Fe≤0.3%, In: 0.001-0.06%, Ga: 0.001-0.06%, Mn: 0.04-0.7%, V: 0.005-0.35%, Mo: 0.005-0 .35%, Zr: 0.02~0.4%, B: 0.004~0.07%, Cr: 0.04~0.7%, Ti: 0.02~0.4%, Be: 0.0002~0.003%, Sc: 0.02~0.5%, Gd: 0.02~0.5%, Dy: 0.02~0.5%, other unavoidable single impurity elements ≤0.04%, the total amount of impurity elements ≤0.20%, the balance is aluminum.

[0007] Furthermore, the die-casting aluminum alloy material includes the following components in mass percentage: including the following components in mass percentage: Cu: 0.1-3.0%, Zn: 0.1-3.0%, Si: 1.0-4.0%, Mg: 2.0-8.5%, Fe≤0.20%, In: 0.004-0.05%, Ga: 0.004-0.05%, Mn: 0.05-0.65%, V: 0.035-0.255%, Mo: 0.02 ~0.255%, Zr: 0.04~0.30%, B: 0.005~0.04%, Cr: 0.15~0.55%, Ti: 0.035~0.155%, Be: 0.0004~0.002%, Sc: 0.04~0.4%, Gd: 0.04~0.4%, Dy: 0.04~0.4%, other unavoidable single impurity elements ≤0.035%, the total amount of impurity elements ≤0.155%, the balance is aluminum.

[0008] The present invention also provides a method for preparing a heat-treatment-free die-cast aluminum alloy material, which comprises subjecting aluminum ingots, metallic silicon, magnesium ingots, electrolytic copper, zinc ingots, aluminum-manganese master alloys, aluminum-chromium master alloys, aluminum-titanium-boron master alloys, aluminum-vanadium master alloys, aluminum-molybdenum master alloys, aluminum-zirconium master alloys, gallium-indium alloys, aluminum-beryllium master alloys, aluminum-scandium master alloys, aluminum-gadolinium master alloys, and aluminum-dysprosium master alloys to smelting, refining, and casting processes to obtain the die-cast aluminum alloy material.

[0009] Furthermore, the gallium-indium alloy is made by smelting and casting metal gallium and metal indium with a purity of not less than 3N, and its content ratio is configured according to the required content, with a gallium content of 30-60% and an indium content of 40-70%; wherein the contents of scandium, gadolinium and dysprosium in the aluminum-scandium master alloy, the aluminum-gadolinium master alloy and the aluminum-dysprosium master alloy are 1.95-2.10%, 9.5-10.5% and 4.8-5.2% respectively, and the content ratio of the three elements of scandium, gadolinium and dysprosium in the die-cast aluminum alloy material is (1-2):(2-4):(1-5).

[0010] The present invention also provides a method for preparing a heat treatment-free die-casting aluminum alloy material, which specifically comprises the following steps:

[0011] Step A, configuring the required raw materials according to the composition of the die-casting aluminum alloy material: magnesium ingot, electrolytic copper, zinc ingot, aluminum ingot, metallic silicon, aluminum-manganese master alloy, aluminum-molybdenum master alloy, aluminum-zirconium master alloy, aluminum-chromium master alloy, aluminum-titanium-boron master alloy, aluminum-beryllium master alloy, aluminum-scandium master alloy, aluminum-gadolinium master alloy, aluminum-dysprosium master alloy, aluminum-vanadium master alloy, and gallium-indium alloy;

[0012] Step B, the first batch of furnace materials: electrolytic copper, zinc ingot, aluminum ingot, metal silicon, aluminum vanadium master alloy, aluminum chromium master alloy, aluminum molybdenum master alloy, aluminum manganese master alloy, aluminum zirconium master alloy are charged into a smelting furnace, heated and melted, and kept warm for the first stage of smelting, and mechanical stirring is applied to the melt during the heat preservation smelting to make each furnace material evenly dispersed; after the first batch of furnace materials are melted and stirred evenly, the second batch of furnace materials: aluminum beryllium master alloy, aluminum scandium master alloy, aluminum gadolinium master alloy, aluminum dysprosium master alloy are added for the second stage of smelting, and mechanical stirring is applied to the melt during the heat preservation smelting to make each furnace material evenly dispersed; after the second batch of furnace materials are melted and stirred evenly, the third batch of furnace materials: gallium indium alloy and magnesium ingot are added for the third stage of smelting, and mechanical stirring is applied to the melt during the heat preservation smelting to make each furnace material evenly dispersed; then a small amount of sample is taken from the high temperature aluminum alloy melt for chemical composition analysis, if the composition is deviated, the composition is adjusted and sampled again for analysis until all elements reach the expected index;

[0013] Step C, refining the aluminum alloy melt in the smelting furnace, then removing the slag in the furnace, sampling and analyzing again after refining, if the composition is still within the expected index range, then proceed to the next process without processing; if the composition deviates, adjust the composition and sample and analyze again, and perform secondary refining and slag removal until all elements reach the expected index before proceeding to the next process;

[0014] Step D, releasing the aluminum alloy melt from the bottom of the furnace for casting, adding aluminum-titanium-boron intermediate alloy wire to the aluminum alloy melt after it enters the flow channel for grain refinement, and after double-stage filtration, the aluminum alloy melt enters the automatic casting machine for casting to obtain a die-cast aluminum alloy ingot.

[0015] Furthermore, in step B, the first stage insulation melting temperature is 750-850°C, the second stage insulation melting temperature is 730-790°C, and the third stage insulation melting temperature is 710-770°C.

[0016] Furthermore, in step C, the mixed gas used in the first refining treatment is prepared by mixing high-purity argon, high-purity nitrogen and high-purity chlorine, wherein 99.99% high-purity argon accounts for 28%, 99.99% high-purity nitrogen accounts for 70%, and 99.99% high-purity chlorine accounts for 2%, and the first refining treatment time is 20 to 70 minutes; the temperature and gas of the secondary refining treatment are the same as those of the first refining treatment, and the secondary refining treatment time is 10 to 35 minutes.

[0017] Furthermore, in step D, the first filter plate of the double-stage filtration is 50-70 mesh, and the second filter plate is 70-90 mesh; the temperature of the aluminum alloy melt above the casting mold is maintained in the range of 630-730°C.

[0018] The invention also provides application of the die-casting aluminum alloy material in die-casting products.

[0019] The present invention also provides a method for manufacturing a die casting, comprising the following steps:

[0020] Step a, remelting and stirring the obtained die-cast aluminum alloy ingot;

[0021] Step b, refining the alloy melt using a mixed gas, followed by slagging and standing to keep warm;

[0022] Step c: using a robotic arm to transfer a certain amount of the melt to a cold chamber die casting machine, die casting it, and obtaining a die casting after cooling.

[0023] Furthermore, in step a, the remelting temperature is 710-770°C; in step b, the refining temperature is 700-740°C, the refining time is 8-35 minutes, and the mixed gas used for the refining treatment is made by mixing high-purity argon, high-purity nitrogen and high-purity chlorine, of which 99.99% high-purity argon accounts for 28%, 99.99% high-purity nitrogen accounts for 70%, and 99.99% high-purity chlorine accounts for 2%; the insulation temperature is 670-730°C.

[0024] Furthermore, in step c, die casting refers to high-pressure die casting. During the die casting process, the first-stage injection speed is 0.15-0.55 m / s, the second-stage injection speed is 1-6 m / s, the third-stage injection speed is 4-21 m / s, the die casting pressure is 55-105 MPa, and the pressure is maintained for 25-95 seconds.

[0025] Rare earth elements Sc, Gd, and Dy have the function of "fixing hydrogen" in aluminum alloys, which is mainly manifested in two aspects. First, rare earth elements are more active and have a greater affinity with H. They can form stable compounds with hydrogen and convert free hydrogen into a compound state. On the other hand, some rare earth-containing intermetallic compounds can chemically adsorb part of the hydrogen and convert free hydrogen into an adsorbed state. The above two functions of rare earth elements can effectively reduce the free hydrogen content in the aluminum alloy melt, thereby inhibiting the precipitation of hydrogen elements and the formation of hydrogen gas during the solidification process, reducing the possibility of hydrogen gas escaping in the cast state, and reducing the cast porosity of the alloy. These rare earth hydrides can be separated from the melt by standing or other means. This behavior is usually called "fixing hydrogen". Rare earth elements can react with Al2O3 inclusions in the aluminum alloy melt to form a certain RE-Al-O multi-phase material. These materials have a higher density than the aluminum melt. Standing can make them sink to the bottom of the crucible to achieve inclusion separation. Rare earth elements can form a class of intermetallic compounds in aluminum alloy systems, such as Al3Sc, Al3Gd, and Al3Dy, which have the characteristics of high melting point and high thermal stability. These intermetallic compounds can serve as the nucleation core of α-Al during the solidification process of aluminum alloy, promoting the nucleation rate of α-Al grains. Rare earth elements will transfer from the solid phase to the liquid phase during the solidification process of the alloy, and enrich on the surface of the Mg2Si phase produced by the eutectic reaction, changing the surface energy state of the Mg2Si phase, reducing its tendency to grow preferentially, thereby improving and refining the morphology of the Mg2Si phase produced by the eutectic reaction, and finally manifesting as a modification of the eutectic structure. Rare earth elements can effectively change the crystallization kinetics of the Fe-rich phase during the solidification process of aluminum alloy, thereby transforming it from a needle-like shape to a smaller fishbone shape, a Chinese character shape, or a short rod shape, thereby improving the plasticity of the alloy.

[0026] Ga and In elements can be enriched on the surface of Mg2Si phase during solidification, changing its surface energy state and the preferred orientation state of Mg2Si phase crystallization, thus playing a metamorphic role.

[0027] The solid solubility of Cu and Zn elements in α-Al is relatively high, which can produce a more obvious solid solution strengthening effect and improve the strength of the alloy.

[0028] The aluminum alloy material of the present invention has a high Mg content. Since the oxide film produced by the Mg element is not dense and cannot protect the surface of the melt, a trace amount of Be element is added during the smelting process of the aluminum alloy with a high Mg content to supplement the cracks in the MgO film, so that a relatively dense oxide film is formed on the surface of the aluminum alloy melt, thereby reducing the burnout of the Mg element in the aluminum alloy melt and controlling the hydrogen content of the melt.

[0029] Mn, Cr, V, Mo, Zr, etc. are all transition metal elements, and their roles in the present invention are mainly divided into two categories. The first category is Mn and Cr elements. On the one hand, Mn elements have a certain solid solution strengthening effect; on the other hand, Mn and Cr elements can change the morphology of the Fe-rich phase, while reducing the size of the Fe-rich phase, improving the plasticity of the aluminum alloy material; on the third hand, the fine intermediate phase formed by Mn, Cr elements and Si and Fe elements has a higher melting point, and under a certain range of high temperature conditions, the diffusion coefficients of Mn and Cr in the aluminum alloy matrix can still be maintained at a lower level, which can improve the high temperature resistance of the aluminum alloy. V, Mo, Zr elements and Al elements can form a complex intermediate phase, and are first precipitated during the casting solidification process, providing crystal nuclei for the formation of aluminum alloy grains, and have the effect of refining aluminum alloy grains; at the same time, the complex intermediate phase formed by V, Mo, Zr and Al has a higher melting point and its diffusion coefficient in the aluminum alloy is lower, so that the intermediate phase formed has a higher thermal stability, improving the high temperature resistance of the aluminum alloy material.

[0030] Ti and B elements are added simultaneously through aluminum-titanium-boron master alloy. Aluminum-titanium-boron is a commonly used grain refiner for aluminum alloys. It is added in the runner after the furnace and before casting to further refine the grain size of the aluminum alloy.

[0031] The present invention has the following beneficial effects due to the adoption of the above technical solution:

[0032] 1. The present invention utilizes the eutectic reaction characteristics of Si, Mg and Al elements within a certain content range, so that the alloy undergoes a eutectic reaction of L→α-Al+Mg2Si during solidification, so that the alloy has good fluidity and casting formability, and is suitable for die-casting production of workpieces with complex shapes.

[0033] 2. The present invention utilizes the effects of high melting point transition metal elements Mn, Cr, V, Mo, and Zr on grain refinement and improved thermal stability, so that the alloy material not only has good room temperature performance, but also can serve for a long time at a certain temperature.

[0034] 3. The present invention comprehensively utilizes rare earth elements, Ga, In, Sr elements and Al-Ti-B to modify and refine grains and eutectic structures, improve and refine the alloy microstructure, and make it have higher strength and plasticity in the die-cast state. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, preferred embodiments are given below to further describe the present invention in detail. However, it should be noted that many details listed in the specification are only for the purpose of enabling the reader to have a thorough understanding of one or more aspects of the present invention, and these aspects of the present invention can be implemented even without these specific details.

[0036] Example 1

[0037] A heat treatment-free die-casting aluminum alloy material, the composition and mass percentage of which are: Si: 1.6%, Mg: 4.1%, Cu: 0.62%, Zn: 0.43%, Fe: 0.13%, Mn: 0.30%, Cr: 0.25%, Ti: 0.08%, V: 0.11%, Mo: 0.10%, Zr: 0.10%, In: 0.008%, Ga: 0.007%, B: 0.01%, Be: 0.0010%, Sc: 0.06%, Gd: 0.12%, Dy: 0.16%, other unavoidable single impurity elements ≤ 0.03%, the total amount of impurity elements ≤ 0.15%, and the balance is aluminum. Among them, the Ga element accounts for 46.7% of the gallium-indium alloy, and the In element accounts for about 53.3%; the ratio of Sc, Gd, and Dy elements is 1.5:3:4.

[0038] A method for preparing a heat treatment-free die-casting aluminum alloy material comprises the following steps:

[0039] Step A, configuring the required raw materials according to the composition of the die-casting aluminum alloy material: magnesium ingot, electrolytic copper, zinc ingot, aluminum ingot, metallic silicon, aluminum-manganese master alloy, aluminum-molybdenum master alloy, aluminum-zirconium master alloy, aluminum-chromium master alloy, aluminum-titanium-boron master alloy, aluminum-beryllium master alloy, aluminum-scandium master alloy, aluminum-gadolinium master alloy, aluminum-dysprosium master alloy, aluminum-vanadium master alloy, and gallium-indium alloy;

[0040] Step B, the first batch of furnace materials: electrolytic copper, zinc ingot, aluminum ingot, metal silicon, aluminum vanadium master alloy, aluminum chromium master alloy, aluminum molybdenum master alloy, aluminum manganese master alloy, aluminum zirconium master alloy are charged into a smelting furnace, heated and melted, and the first stage smelting is performed at 780°C, and mechanical stirring is applied to the melt during the heat preservation smelting to uniformly disperse the alloy elements; the above furnace materials are melted and stirred uniformly, and the temperature is lowered to 760°C, and then the second batch of furnace materials: aluminum beryllium master alloy, aluminum scandium master alloy, aluminum gadolinium master alloy, aluminum dysprosium master alloy are added. , after being completely melted, it is kept at 760℃ for smelting and mechanically stirred to evenly disperse the alloy elements; the above-mentioned charge is melted and stirred evenly, and then the temperature is lowered to 740℃, and the third batch of charge is added: magnesium ingot and gallium-indium alloy. After being completely melted, it is kept at 715℃~745℃ for smelting and mechanically stirred to evenly disperse the alloy elements; then a small amount of sample is taken from the high-temperature aluminum alloy melt and solidified for chemical composition analysis. If there is a deviation in the composition, the composition is adjusted and sampled again for analysis until all elements reach the expected indicators;

[0041] Step C, using a mixed gas of 99.99% high-purity argon accounting for 28%, 99.99% high-purity nitrogen accounting for 70%, and 99.99% high-purity chlorine accounting for 2% to perform a refining treatment on the aluminum alloy melt in the furnace, the treatment time is 50 minutes, and then the slag in the furnace is fished out, and after the refining is completed, sampling and analysis are performed again. If the composition is still within the expected index range, no treatment is required to enter the next process; if the composition deviates, the composition is adjusted and sampling and analysis are performed again, and secondary refining and slag removal are performed until all elements reach the expected index before entering the next process;

[0042] Step D, when the temperature of the aluminum alloy melt in the smelting furnace reaches 710-725°C, the aluminum alloy melt is released from the bottom of the furnace for casting, and when the aluminum alloy melt enters the flow channel, aluminum-titanium-boron intermediate alloy wire is added thereto for grain refinement. The aluminum alloy melt is filtered through a first-stage filter plate with 60 mesh and a second-stage filter plate with 80 mesh, and then enters an automatic casting machine for casting to obtain a die-cast aluminum alloy ingot. The temperature of the aluminum alloy melt above the casting mold is 695°C, and alloy ingots of die-cast aluminum alloy material are obtained, and each alloy ingot weighs about 5 kg.

[0043] The high pressure die casting process of die casting parts is as follows:

[0044] Step a, remelting the obtained die-cast aluminum alloy ingot at 740° C. and stirring to make the alloy elements dispersed evenly;

[0045] Step b, when the temperature of the aluminum alloy melt drops to 720°C, the alloy melt is refined using a mixed gas consisting of 28% of 99.99% high-purity argon, 70% of 99.99% high-purity nitrogen, and 2% of 99.99% high-purity chlorine. The refining lasts for 15 minutes, followed by slagging and keeping the temperature at 685°C for insulation in preparation for high-pressure die casting. During the entire high-pressure die casting process, the aluminum alloy melt in the furnace is required to be maintained at 685-695°C;

[0046] Step c, using an automatic soup taking robot arm to transfer a certain amount of alloy melt from the melting furnace to the barrel of the cold chamber die casting machine for high-pressure die casting. During the die casting process, the first-stage injection speed is 0.25m / s, the second-stage injection speed is 2.5m / s, and the third-stage injection speed is 8.0m / s. The die casting pressure is 85MPa. After holding the pressure for 45 seconds, the workpiece is taken out of the die casting machine mold using a robot arm, and the die casting is obtained after cooling.

[0047] Example 2

[0048] A heat treatment-free die-casting aluminum alloy material, the composition and mass percentage of which are: Si: 3.1%, Mg: 4.1%, Cu: 1.3%, Zn: 0.83%, Fe: 0.10%, Mn: 0.36%, Cr: 0.17%, Ti: 0.10%, V: 0.16%, Mo: 0.20%, Zr: 0.13%, In: 0.01%, Ga: 0.008%, B: 0.02%, Be: 0.0006%, Sc: 0.11%, Gd: 0.22%, Dy: 0.15%, other unavoidable single impurity elements ≤ 0.03%, the total amount of impurity elements ≤ 0.15%, and the balance is aluminum. Among them, the Ga element accounts for 45.5% of the gallium-indium alloy, and the In element accounts for about 55.5%; the ratio of Sc, Gd, and Dy elements is 1.5:3:4.

[0049] A method for preparing a heat treatment-free die-casting aluminum alloy material comprises the following steps:

[0050] Step A, configuring the required raw materials according to the composition of the die-casting aluminum alloy material: magnesium ingot, electrolytic copper, zinc ingot, aluminum ingot, metallic silicon, aluminum-manganese master alloy, aluminum-molybdenum master alloy, aluminum-zirconium master alloy, aluminum-chromium master alloy, aluminum-titanium-boron master alloy, aluminum-beryllium master alloy, aluminum-scandium master alloy, aluminum-gadolinium master alloy, aluminum-dysprosium master alloy, aluminum-vanadium master alloy, and gallium-indium alloy;

[0051] Step B, the first batch of furnace materials: electrolytic copper, zinc ingot, aluminum ingot, metal silicon, aluminum vanadium master alloy, aluminum chromium master alloy, aluminum molybdenum master alloy, aluminum manganese master alloy, aluminum zirconium master alloy are charged into a smelting furnace, heated and melted, and the first stage smelting is performed at 780°C, and mechanical stirring is applied to the melt during the heat preservation smelting to uniformly disperse the alloy elements; the above furnace materials are melted and stirred uniformly, and the temperature is lowered to 760°C, and then the second batch of furnace materials: aluminum beryllium master alloy, aluminum scandium master alloy, aluminum gadolinium master alloy, aluminum dysprosium master alloy are added. , after being completely melted, it is kept at 760℃ for smelting and mechanically stirred to evenly disperse the alloy elements; the above-mentioned charge is melted and stirred evenly, and then the temperature is lowered to 740℃, and the third batch of charge is added: magnesium ingot and gallium-indium alloy. After being completely melted, it is kept at 715℃~745℃ for smelting and mechanically stirred to evenly disperse the alloy elements; then a small amount of sample is taken from the high-temperature aluminum alloy melt and solidified for chemical composition analysis. If there is a deviation in the composition, the composition is adjusted and sampled again for analysis until all elements reach the expected indicators;

[0052] Step C, using a mixed gas of 99.99% high-purity argon accounting for 28%, 99.99% high-purity nitrogen accounting for 70%, and 99.99% high-purity chlorine accounting for 2% to perform a refining treatment on the aluminum alloy melt in the furnace, the treatment time is 50 minutes, and then the slag in the furnace is fished out, and after the refining is completed, sampling and analysis are performed again. If the composition is still within the expected index range, no treatment is required to enter the next process; if the composition deviates, the composition is adjusted and sampling and analysis are performed again, and secondary refining and slag removal are performed until all elements reach the expected index before entering the next process;

[0053] Step D, when the temperature of the aluminum alloy melt in the smelting furnace reaches 710-725°C, the aluminum alloy melt is released from the bottom of the furnace for casting, and when the aluminum alloy melt enters the flow channel, aluminum-titanium-boron intermediate alloy wire is added thereto for grain refinement. The aluminum alloy melt is filtered through a first-stage filter plate with 60 mesh and a second-stage filter plate with 80 mesh, and then enters an automatic casting machine for casting to obtain a die-cast aluminum alloy ingot. The temperature of the aluminum alloy melt above the casting mold is 695°C, and alloy ingots of die-cast aluminum alloy material are obtained, and each alloy ingot weighs about 5 kg.

[0054] The high pressure die casting process of die casting parts is as follows:

[0055] Step a, remelting the obtained die-cast aluminum alloy ingot at 735° C. and stirring to make the alloy elements dispersed evenly;

[0056] Step b, when the temperature of the aluminum alloy melt drops to 720°C, the alloy melt is refined using a mixed gas consisting of 28% of 99.99% high-purity argon, 70% of 99.99% high-purity nitrogen, and 2% of 99.99% high-purity chlorine. The refining lasts for 20 minutes, followed by slagging and keeping the temperature at 700°C for insulation in preparation for high-pressure die casting. During the entire high-pressure die casting process, the aluminum alloy melt in the furnace is required to be maintained at 700°C;

[0057] Step c, using an automatic soup taking robot arm to transfer a certain amount of alloy melt from the melting furnace to the barrel of the cold chamber die casting machine for high-pressure die casting. During the die casting process, the first-stage injection speed is 0.30m / s, the second-stage injection speed is 3.0m / s, and the third-stage injection speed is 10.0m / s. The die casting pressure is 75MPa. After holding the pressure for 80 seconds, the workpiece is taken out of the die casting machine mold using a robot arm, and the die casting is obtained after cooling.

[0058] Example 3

[0059] A heat treatment-free die-casting aluminum alloy material, the composition and mass percentage of which are: Si: 2.8%, Mg: 7.2%, Cu: 0.65%, Zn: 1.24%, Fe: 0.09%, Mn: 0.33%, Cr: 0.21%, Ti: 0.12%, V: 0.23%, Mo: 0.19%, Zr: 0.16%, In: 0.02%, Ga: 0.03%, B: 0.024%, Be: 0.0014%, Sc: 0.13%, Gd: 0.23%, Dy: 0.07%, other unavoidable single impurity elements ≤ 0.03%, the total amount of impurity elements ≤ 0.15%, and the balance is aluminum. Among them, the Ga element accounts for 60% of the gallium-indium alloy, and the In element accounts for about 40%; the ratio of Sc, Gd, and Dy elements is 1.8:3.3:1.

[0060] A method for preparing a heat treatment-free die-casting aluminum alloy material comprises the following steps:

[0061] Step A, configuring the required raw materials according to the composition of the die-casting aluminum alloy material: magnesium ingot, electrolytic copper, zinc ingot, aluminum ingot, metallic silicon, aluminum-manganese master alloy, aluminum-molybdenum master alloy, aluminum-zirconium master alloy, aluminum-chromium master alloy, aluminum-titanium-boron master alloy, aluminum-beryllium master alloy, aluminum-scandium master alloy, aluminum-gadolinium master alloy, aluminum-dysprosium master alloy, aluminum-vanadium master alloy, and gallium-indium alloy;

[0062] Step B, the first batch of furnace materials: electrolytic copper, zinc ingot, aluminum ingot, metal silicon, aluminum vanadium master alloy, aluminum chromium master alloy, aluminum molybdenum master alloy, aluminum manganese master alloy, aluminum zirconium master alloy are charged into a smelting furnace, heated and melted, and the first stage smelting is carried out at 790° C. During the heat preservation smelting, mechanical stirring is applied to the melt to uniformly disperse the alloy elements; the above furnace materials are melted and stirred uniformly, and then the temperature is lowered to 750° C., and the second batch of furnace materials: aluminum beryllium master alloy, aluminum scandium master alloy, aluminum gadolinium master alloy, aluminum dysprosium master alloy are added. , after being completely melted, they are kept at 750℃ for smelting and mechanically stirred to evenly disperse the alloy elements; the above-mentioned charge is melted and stirred evenly, and then the temperature is lowered to 740℃, and then the third batch of charge is added: magnesium ingot and gallium-indium alloy. After being completely melted, they are kept at 725℃~745℃ for smelting and mechanically stirred to evenly disperse the alloy elements; then a small amount of sample is taken from the high-temperature aluminum alloy melt and solidified for chemical composition analysis. If there is a deviation in the composition, the composition is adjusted and sampled again for analysis until all elements reach the expected indicators;

[0063] Step C, using a mixed gas of 99.99% high-purity argon accounting for 28%, 99.99% high-purity nitrogen accounting for 70%, and 99.99% high-purity chlorine accounting for 2% to perform a refining treatment on the aluminum alloy melt in the furnace, the treatment time is 60 minutes, and then the slag in the furnace is fished out, and after the refining is completed, sampling and analysis are performed again. If the composition is still within the expected index range, no treatment is required to enter the next process; if the composition deviates, the composition is adjusted and sampling and analysis are performed again, and secondary refining and slag removal treatment are performed until all elements reach the expected index before entering the next process;

[0064] Step D, when the temperature of the aluminum alloy melt in the smelting furnace reaches 710-725°C, the aluminum alloy melt is released from the bottom of the furnace for casting, and when the aluminum alloy melt enters the flow channel, aluminum-titanium-boron intermediate alloy wire is added thereto for grain refinement. The aluminum alloy melt is filtered through a first-stage filter plate with 60 mesh and a second-stage filter plate with 80 mesh, and then enters an automatic casting machine for casting to obtain a die-cast aluminum alloy ingot. The temperature of the aluminum alloy melt above the casting mold is 705°C, and an alloy ingot of die-cast aluminum alloy material is obtained, and each alloy ingot weighs about 5 kg.

[0065] The high pressure die casting process of die casting parts is as follows:

[0066] Step a, remelting the obtained die-cast aluminum alloy ingot at 745° C. and stirring to make the alloy elements dispersed evenly;

[0067] Step b, when the temperature of the aluminum alloy melt drops to 730°C, the alloy melt is refined using a mixed gas consisting of 28% of 99.99% high-purity argon, 70% of 99.99% high-purity nitrogen, and 2% of 99.99% high-purity chlorine. The refining lasts for 20 minutes, followed by slagging and keeping the temperature at 685°C for insulation in preparation for high-pressure die casting. The aluminum alloy melt in the furnace is required to be maintained at 685°C during the entire high-pressure die casting process;

[0068] Step c, using an automatic soup taking robot arm to transfer a certain amount of alloy melt from the melting furnace to the barrel of the cold chamber die casting machine for high-pressure die casting. During the die casting process, the first-stage injection speed is 0.40m / s, the second-stage injection speed is 4.0m / s, and the third-stage injection speed is 15.0m / s. The die casting pressure is 95MPa. After holding the pressure for 90 seconds, the workpiece is taken out of the die casting machine mold using a robot arm, and the die casting is obtained after cooling.

[0069] Example 4

[0070] A heat treatment-free die-casting aluminum alloy material, the composition and mass percentage of which are: Si: 2.0%, Mg: 5.0%, Cu: 0.75%, Zn: 0.5%, Fe: 0.11%, Mn: 0.34%, Cr: 0.24%, Ti: 0.09%, V: 0.15%, Mo: 0.14%, Zr: 0.14%, In: 0.015%, Ga: 0.05%, B: 0.015%, Be: 0.0012%, Sc: 0.08%, Gd: 0.15%, Dy: 0.10%, other unavoidable single impurity elements ≤ 0.03%, the total amount of impurity elements ≤ 0.15%, and the balance is aluminum. Among them, the Ga element accounts for 60% of the gallium-indium alloy, and the In element accounts for about 40%; the ratio of Sc, Gd, and Dy elements is 1.6:3.1:2.

[0071] A method for preparing a heat treatment-free die-casting aluminum alloy material comprises the following steps:

[0072] Step A, configuring the required raw materials according to the composition of the die-casting aluminum alloy material: magnesium ingot, electrolytic copper, zinc ingot, aluminum ingot, metallic silicon, aluminum-manganese master alloy, aluminum-molybdenum master alloy, aluminum-zirconium master alloy, aluminum-chromium master alloy, aluminum-titanium-boron master alloy, aluminum-beryllium master alloy, aluminum-scandium master alloy, aluminum-gadolinium master alloy, aluminum-dysprosium master alloy, aluminum-vanadium master alloy, and gallium-indium alloy;

[0073] Step B, the first batch of furnace materials: electrolytic copper, zinc ingot, aluminum ingot, metal silicon, aluminum vanadium master alloy, aluminum chromium master alloy, aluminum molybdenum master alloy, aluminum manganese master alloy, aluminum zirconium master alloy are charged into a smelting furnace, heated and melted, and the first stage smelting is carried out at 790° C. During the heat preservation smelting, mechanical stirring is applied to the melt to uniformly disperse the alloy elements; the above furnace materials are melted and stirred uniformly, and then the temperature is lowered to 750° C., and the second batch of furnace materials: aluminum beryllium master alloy, aluminum scandium master alloy, aluminum gadolinium master alloy, aluminum dysprosium master alloy are added. , after being completely melted, they are kept at 750℃ for smelting and mechanically stirred to evenly disperse the alloy elements; the above-mentioned furnace materials are melted and stirred evenly, and then the temperature is lowered to 740℃, and the third batch of furnace materials: magnesium ingots and gallium-indium alloys are added. After being completely melted, they are kept at 735℃~745℃ for smelting and mechanically stirred to evenly disperse the alloy elements; then a small amount of samples are taken from the high-temperature aluminum alloy melt and solidified for chemical composition analysis. If there is a deviation in the composition, the composition is adjusted and sampled again for analysis until all elements reach the expected indicators;

[0074] Step C, using a mixed gas of 99.99% high-purity argon accounting for 28%, 99.99% high-purity nitrogen accounting for 70%, and 99.99% high-purity chlorine accounting for 2% to perform a refining treatment on the aluminum alloy melt in the furnace, the treatment time is 60 minutes, and then the slag in the furnace is fished out, and after the refining is completed, sampling and analysis are performed again. If the composition is still within the expected index range, no treatment is required to enter the next process; if the composition deviates, the composition is adjusted and sampling and analysis are performed again, and secondary refining and slag removal treatment are performed until all elements reach the expected index before entering the next process;

[0075] Step D, when the temperature of the aluminum alloy melt in the smelting furnace reaches 715-725°C, the aluminum alloy melt is released from the bottom of the furnace for casting, and when the aluminum alloy melt enters the flow channel, aluminum-titanium-boron intermediate alloy wire is added thereto for grain refinement. The aluminum alloy melt is filtered through a first-stage filter plate with 60 mesh and a second-stage filter plate with 80 mesh, and then enters an automatic casting machine for casting to obtain a die-cast aluminum alloy ingot. The temperature of the aluminum alloy melt above the casting mold is 705°C, and an alloy ingot of die-cast aluminum alloy material is obtained, and each alloy ingot weighs about 5 kg.

[0076] The high pressure die casting process of die casting parts is as follows:

[0077] Step a, remelting the obtained die-cast aluminum alloy ingot at 745° C. and stirring to uniformly disperse the alloy elements;

[0078] Step b, when the temperature of the aluminum alloy melt drops to 730°C, the alloy melt is refined using a mixed gas consisting of 28% of 99.99% high-purity argon, 70% of 99.99% high-purity nitrogen, and 2% of 99.99% high-purity chlorine. The refining lasts for 20 minutes, followed by slagging and keeping the temperature at 685°C for insulation in preparation for high-pressure die casting. The aluminum alloy melt in the furnace is required to be maintained at 685°C during the entire high-pressure die casting process;

[0079] Step c, using an automatic soup taking robot arm to transfer a certain amount of alloy melt from the melting furnace to the barrel of the cold chamber die casting machine for high-pressure die casting. During the die casting process, the first-stage injection speed is 0.40m / s, the second-stage injection speed is 4.0m / s, and the third-stage injection speed is 15.0m / s. The die casting pressure is 95MPa. After holding the pressure for 90 seconds, the workpiece is taken out of the die casting machine mold using a robot arm, and the die casting is obtained after cooling.

[0080] Example 5

[0081] A heat treatment-free die-casting aluminum alloy material, the composition and mass percentage of which are: Si: 2.4%, Mg: 6.2%, Cu: 0.85%, Zn: 0.9%, Fe: 0.12%, Mn: 0.35%, Cr: 0.19%, Ti: 0.11%, V: 0.20%, Mo: 0.16%, Zr: 0.15%, In: 0.18%, Ga: 0.06%, B: 0.018%, Be: 0.0013%, Sc: 0.10%, Gd: 0.20%, Dy: 0.08%, other unavoidable single impurity elements ≤ 0.03%, the total amount of impurity elements ≤ 0.15%, and the balance is aluminum. Among them, the Ga element accounts for 60% of the gallium-indium alloy, and the In element accounts for about 40%; the ratio of Sc, Gd, and Dy elements is 1.7:3.2:3.

[0082] A method for preparing a heat treatment-free die-casting aluminum alloy material comprises the following steps:

[0083] Step A, configuring the required raw materials according to the composition of the die-casting aluminum alloy material: magnesium ingot, electrolytic copper, zinc ingot, aluminum ingot, metallic silicon, aluminum-manganese master alloy, aluminum-molybdenum master alloy, aluminum-zirconium master alloy, aluminum-chromium master alloy, aluminum-titanium-boron master alloy, aluminum-beryllium master alloy, aluminum-scandium master alloy, aluminum-gadolinium master alloy, aluminum-dysprosium master alloy, aluminum-vanadium master alloy, and gallium-indium alloy;

[0084] Step B, the first batch of furnace materials: electrolytic copper, zinc ingot, aluminum ingot, metal silicon, aluminum vanadium master alloy, aluminum chromium master alloy, aluminum molybdenum master alloy, aluminum manganese master alloy, aluminum zirconium master alloy are charged into a smelting furnace, heated and melted, and the first stage smelting is carried out at 790° C. During the heat preservation smelting, mechanical stirring is applied to the melt to uniformly disperse the alloy elements; the above furnace materials are melted and stirred uniformly, and then the temperature is lowered to 750° C., and the second batch of furnace materials: aluminum beryllium master alloy, aluminum scandium master alloy, aluminum gadolinium master alloy, aluminum dysprosium master alloy are added. , after being completely melted, they are kept at 750℃ for smelting and mechanically stirred to evenly disperse the alloy elements; the above-mentioned furnace materials are melted and stirred evenly, and then the temperature is lowered to 740℃, and the third batch of furnace materials: magnesium ingots and gallium-indium alloys are added. After being completely melted, they are kept at 725℃~740℃ for smelting and mechanically stirred to evenly disperse the alloy elements; then a small amount of samples are taken from the high-temperature aluminum alloy melt and solidified for chemical composition analysis. If there is a deviation in the composition, the composition is adjusted and sampled again for analysis until all elements reach the expected indicators;

[0085] Step C, using a mixed gas of 99.99% high-purity argon accounting for 28%, 99.99% high-purity nitrogen accounting for 70%, and 99.99% high-purity chlorine accounting for 2% to perform a refining treatment on the aluminum alloy melt in the furnace, the treatment time is 60 minutes, and then the slag in the furnace is fished out, and after the refining is completed, sampling and analysis are performed again. If the composition is still within the expected index range, no treatment is required to enter the next process; if the composition deviates, the composition is adjusted and sampling and analysis are performed again, and secondary refining and slag removal treatment are performed until all elements reach the expected index before entering the next process;

[0086] Step D, when the temperature of the aluminum alloy melt in the smelting furnace reaches 710-720°C, the aluminum alloy melt is released from the bottom of the furnace for casting, and when the aluminum alloy melt enters the flow channel, aluminum-titanium-boron intermediate alloy wire is added thereto for grain refinement. The aluminum alloy melt is filtered through a first-stage filter plate with 60 mesh and a second-stage filter plate with 80 mesh, and then enters an automatic casting machine for casting to obtain a die-cast aluminum alloy ingot. The temperature of the aluminum alloy melt above the casting mold is 705°C, and alloy ingots of die-cast aluminum alloy material are obtained, and each alloy ingot weighs about 5 kg.

[0087] The high pressure die casting process of die casting parts is as follows:

[0088] Step a, remelting the obtained die-cast aluminum alloy ingot at 745° C. and stirring to uniformly disperse the alloy elements;

[0089] Step b, when the temperature of the aluminum alloy melt drops to 730°C, the alloy melt is refined using a mixed gas consisting of 28% of 99.99% high-purity argon, 70% of 99.99% high-purity nitrogen, and 2% of 99.99% high-purity chlorine. The refining lasts for 20 minutes, followed by slagging and keeping the temperature at 685°C for insulation in preparation for high-pressure die casting. The aluminum alloy melt in the furnace is required to be maintained at 685°C during the entire high-pressure die casting process;

[0090] Step c, using an automatic soup taking robot arm to transfer a certain amount of alloy melt from the melting furnace to the barrel of the cold chamber die casting machine for high-pressure die casting. During the die casting process, the first-stage injection speed is 0.40m / s, the second-stage injection speed is 4.0m / s, and the third-stage injection speed is 15.0m / s. The die casting pressure is 95MPa. After holding the pressure for 90 seconds, the workpiece is taken out of the die casting machine mold using a robot arm, and the die casting is obtained after cooling.

[0091] Comparative Example 1

[0092] The die castings produced by ADC12 alloy are compared. The mass percentage of ADC12 alloy composition is: Si: 11.2%, Mg: 0.19%, Cu: 2.0%, Mn: 0.42%, Zn: 0.66%, Ti: 0.13%, Fe: 0.87%, other unavoidable single impurity elements ≤ 0.03%, the total amount of impurity elements ≤ 0.15%, and the balance is aluminum. The die casting temperature of ADC12 alloy is 660℃, the first stage injection speed is 0.4m / s, the second stage injection speed is 4.5m / s, the third stage injection speed is 15.0m / s, the die casting pressure is 80MPa, and the die casting is obtained after cooling.

[0093] Comparative Example 2

[0094] The die castings produced by A380 alloy are compared. The mass percentage of the A380 alloy composition is: Si: 8.0%, Mg: 0.09%, Cu: 3.4%, Mn: 0.40%, Ni: 0.36%, Zn: 1.8%, Ti: 0.08%, Fe: 1.04%, other unavoidable single impurity elements ≤ 0.03%, the total amount of impurity elements ≤ 0.15%, and the balance is aluminum. The die casting temperature of A380 alloy is 670℃, the first stage injection speed is 0.4m / s, the second stage injection speed is 4.0m / s, the third stage injection speed is 15.0m / s, the die casting pressure is 80MPa, and the die casting workpiece is obtained after cooling.

[0095] Performance Testing

[0096] The die castings prepared in the above Examples 1-5 and the die castings prepared in Comparative Examples 1 and 2 were tested as follows:

[0097] 1. Mechanical properties test

[0098] The die castings prepared in Examples 1-5 and Comparative Examples 1 and 2 were sampled and tested for mechanical properties to examine their yield strength, tensile strength, and elongation after fracture. The results are shown in Table 1:

[0099] Table 1 Mechanical properties test results

[0100] Alloy Material Yield Strength Tensile strength(MPa) Elongation after break (%) Example 1 286 346 9.9 Example 2 293 353 8.8 Example 3 304 356 8.6 Example 4 290 348 9.5 Example 5 298 350 8.7 ADC12 alloy 234 276 2.0 A380 Alloy 241 334 1.8

[0101] It can be seen from Tables 1-3 that the mechanical properties and plasticity of the die castings obtained in Examples 1-5 of the present invention are better than those of the die castings prepared using ADC12 and A380 alloys, and have excellent performance.

[0102] Rare earth elements scandium (Sc), gadolinium (Gd), and dysprosium (Dy) have many beneficial effects in aluminum alloys, such as melt purification, grain refinement, eutectic structure modification, plasticity improvement, and strength enhancement. They are one of the important ways to develop new aluminum alloy materials.

[0103] In view of the shortcomings of the current die-cast aluminum alloy material performance and the lack of high-strength and toughness heat-treatment-free die-cast aluminum alloy materials, the present invention uses rare earth micro-alloying as a way to develop a heat-treatment-free die-cast aluminum alloy material with high strength and toughness to meet the development needs of the automotive industry.

[0104] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A heat treatment-free die-casting aluminum alloy material, characterized in that: The composition includes the following mass percentages: Cu: 0.02-3.5%, Zn: 0.02-3.5%, Si: 0.5-4.5%, Mg: 1.0-9.0%, Fe≤0.3%, In: 0.001-0.06%, Ga: 0.001-0.06%, Mn: 0.04-0.7%, V: 0.005-0.35%, Mo: 0.005-0.35%, Zr : 0.02~0.4%, B: 0.004~0.07%, Cr: 0.04~0.7%, Ti: 0.02~0.4%, Be: 0.0002~0.003%, Sc: 0.02~0.5%, Gd: 0.02~0.5%, Dy: 0.02~0.5%, other unavoidable single impurity elements ≤0.04%, the total amount of impurity elements ≤0.20%, the balance is aluminum.

2. The heat treatment-free die-casting aluminum alloy material according to claim 1, characterized in that: The invention comprises the following components in mass percentage: Cu: 0.1-3.0%, Zn: 0.1-3.0%, Si: 1.0-4.0%, Mg: 2.0-8.5%, Fe≤0.20%, In: 0.004-0.05%, Ga: 0.004-0.05%, Mn: 0.05-0.65%, V: 0.035-0.255%, Mo: 0.02-0.255%, Zr:

0. 04~0.30%, B: 0.005~0.04%, Cr: 0.15~0.55%, Ti: 0.035~0.155%, Be: 0.0004~0.002%, Sc: 0.04~0.4%, Gd: 0.04~0.4%, Dy: 0.04~0.4%, other unavoidable single impurity elements ≤0.035%, the total amount of impurity elements ≤0.155%, the balance is aluminum.

3. The method for preparing a heat treatment-free die-casting aluminum alloy material according to claim 1 or 2, characterized in that: The following steps are involved: Step A, configuring the required raw materials according to the composition of the die-casting aluminum alloy material: magnesium ingot, electrolytic copper, zinc ingot, aluminum ingot, metallic silicon, aluminum-manganese master alloy, aluminum-molybdenum master alloy, aluminum-zirconium master alloy, aluminum-chromium master alloy, aluminum-titanium-boron master alloy, aluminum-beryllium master alloy, aluminum-scandium master alloy, aluminum-gadolinium master alloy, aluminum-dysprosium master alloy, aluminum-vanadium master alloy, and gallium-indium alloy; Step B, loading the first batch of furnace materials: electrolytic copper, zinc ingot, aluminum ingot, metallic silicon, aluminum-vanadium master alloy, aluminum-chromium master alloy, aluminum-molybdenum master alloy, aluminum-manganese master alloy, and aluminum-zirconium master alloy into a smelting furnace, heating and melting, and keeping warm for the first stage of smelting, and applying mechanical stirring to the melt during the heat preservation smelting to make the various furnace materials evenly dispersed; after the first batch of furnace materials are melted and stirred evenly, adding the second batch of furnace materials: aluminum-beryllium master alloy, aluminum-scandium master alloy, aluminum-gadolinium master alloy, and aluminum-dysprosium master alloy for the second stage of smelting, and applying mechanical stirring to the melt during the heat preservation smelting to make the various furnace materials evenly dispersed; after the second batch of furnace materials are melted and stirred evenly, adding the third batch of furnace materials: gallium-indium alloy and magnesium ingot for the third stage of smelting, and applying mechanical stirring to the melt during the heat preservation smelting to make the various furnace materials evenly dispersed; Then, a small amount of sample is taken from the high-temperature aluminum alloy melt for chemical composition analysis. If the composition is deviated, the composition is adjusted and sampled again for analysis until all elements reach the expected indicators. Step C, refining the aluminum alloy melt in the smelting furnace, then removing the slag in the furnace, sampling and analyzing again after refining, if the composition is still within the expected index range, then proceed to the next process without processing; if the composition deviates, adjust the composition and sample and analyze again, and perform secondary refining and slag removal until all elements reach the expected index before proceeding to the next process; Step D, releasing the aluminum alloy melt from the bottom of the furnace for casting, adding aluminum-titanium-boron intermediate alloy wire to the aluminum alloy melt after it enters the flow channel for grain refinement, and after double-stage filtration, the aluminum alloy melt enters the automatic casting machine for casting to obtain a die-cast aluminum alloy ingot.

4. The method for preparing a heat treatment-free die-casting aluminum alloy material according to claim 3, characterized in that: In step B, the first stage heat preservation and melting temperature is 750-850°C, the second stage heat preservation and melting temperature is 730-790°C, and the third stage heat preservation and melting temperature is 710-770°C.

5. The method for preparing a heat treatment-free die-casting aluminum alloy material according to claim 3, characterized in that: In step C, the mixed gas used in the first refining treatment is prepared by mixing high-purity argon, high-purity nitrogen and high-purity chlorine, wherein 99.99% high-purity argon accounts for 28%, 99.99% high-purity nitrogen accounts for 70%, and 99.99% high-purity chlorine accounts for 2%. The first refining treatment time is 20 to 70 minutes; the temperature and gas of the second refining treatment are the same as those of the first refining treatment, and the second refining treatment time is 10 to 35 minutes.

6. The method for preparing a heat treatment-free die-casting aluminum alloy material according to claim 3, characterized in that: In step D, the first filter plate of the double-stage filtration is 50-70 mesh, and the second filter plate is 70-90 mesh; the temperature of the aluminum alloy melt above the casting mold is maintained in the range of 630-730°C.

7. Use of the die-casting aluminum alloy material according to claim 1 or 2 in die-casting products.

8. A method for manufacturing a die casting according to claim 7, characterized in that: The following steps are involved: Step a, remelting and stirring the die-cast aluminum alloy ingot obtained in claim 3; Step b, refining the alloy melt using a mixed gas, followed by slagging and standing to keep warm; Step c: using a robotic arm to transfer a certain amount of the melt to a cold chamber die casting machine, die casting it, and obtaining a die casting after cooling.

9. The method for manufacturing a die casting according to claim 8, characterized in that: In step a, the remelting temperature is 710-770°C; in step b, the refining temperature is 700-740°C, the refining time is 8-35 minutes, and the mixed gas used for the refining process is made by mixing high-purity argon, high-purity nitrogen and high-purity chlorine, of which 99.99% high-purity argon accounts for 28%, 99.99% high-purity nitrogen accounts for 70%, and 99.99% high-purity chlorine accounts for 2%; the insulation temperature is 670-730°C.

10. The method for manufacturing a die casting according to claim 8, characterized in that: In step c, die casting refers to high pressure die casting, and the first stage injection speed during the die casting process is 0.15 to 0.55 m / s, and the second stage injection speed is 0.15 to 0.55 m / s. The first stage injection speed is 1~6m / s, the third stage injection speed is 4~21m / s, and the die casting pressure is 55~105MPa. Maintain pressure for 25 to 95 seconds.