Heat-treatment-free ZL101A aluminum alloy and preparation method thereof

Abstract

The invention provides a heat treatment-free ZL101A aluminum alloy and a preparation method thereof. The heat-treatment-free ZL101A aluminum alloy is prepared from the following components in percentage by mass: 6.5 to 7.5 percent of Si element, 0.2 to 0.4 percent of Mg element, 0.05 to 0.9 percent of Sc element, 0.05 to 0.9 percent of Er element, 0.1 to 0.2 percent of Ti element, less than or equal to 0.1 percent of Mn element, less than or equal to 0.2 percent of Fe element, less than or equal to 0.2 percent of Cu element and the balance of Al element, wherein reinforcing particles are further added into the heat treatment-free ZL101A aluminum alloy, and the mass ratio of the reinforcing particles in the heat treatment-free ZL101A aluminum alloy is 0.1%-3%. According to the heat-treatment-free ZL101A aluminum alloy, the mechanical property of the heat-treatment-free ZL101A aluminum alloy is improved, and the strength and toughness of the heat-treatment-free ZL101A aluminum alloy in a cast state are improved.

Description

Technical Field

[0001] The invention relates to the technical field of alloy casting, and in particular to a heat treatment-free ZL101A aluminum alloy and a preparation method thereof. Background Art

[0002] ZL101A is a typical cast aluminum alloy with the advantages of good fluidity, high casting strength, heat treatment strengthening, low thermal cracking tendency, low thermal expansion coefficient, good wear resistance and corrosion resistance. It is widely used in rail transportation, aerospace and other fields. In recent years, new energy vehicles and other industrial fields have put forward higher requirements on the comprehensive mechanical properties of ZL101A. In order to break through the tensile limit of traditional ZL101A materials and broaden its application prospects as structural components, people have adopted a variety of means such as microalloying, particle reinforcement, and heat treatment strengthening to further improve its comprehensive mechanical properties.

[0003] However, the microalloying and particle reinforcement heat treatment in the prior art have limited effect on improving the mechanical properties of ZL101A material.

[0004] Although heat treatment strengthening can further improve the mechanical properties of aluminum alloys. However, for large thin-walled parts, deformation may occur during the heat treatment process, resulting in the scrapping of parts. Generally, it is improved by means of shape correction tooling. If the performance of aluminum alloy in the cast state can meet the use requirements, subsequent heat treatment is not necessary, reducing the process. Therefore, the development of high-strength and tough aluminum alloys without heat treatment has broad application prospects. Summary of the invention

[0005] The main purpose of the present invention is to provide a heat-treatment-free ZL101A aluminum alloy and a preparation method thereof, so as to solve the problems in the prior art that the casting method of the ZL101A aluminum alloy is difficult to avoid heat treatment and the mechanical properties of the obtained ZL101A aluminum alloy are poor.

[0006] To achieve the above-mentioned purpose, according to one aspect of the present invention, a heat-treatment-free ZL101A aluminum alloy is provided. The heat-treatment-free ZL101A aluminum alloy comprises, in terms of mass percentage, 6.5% to 7.5% of Si element, 0.2% to 0.4% of Mg element, 0.05% to 0.9% of Sc element, 0.05% to 0.9% of Er element, 0.1% to 0.2% of Ti element, ≤0.1% of Mn element, ≤0.2% of Fe element, ≤0.2% of Cu element, and the rest is Al element; wherein, reinforcing particles are further added to the heat-treatment-free ZL101A aluminum alloy, and the mass proportion of the reinforcing particles in the heat-treatment-free ZL101A aluminum alloy is 0.1% to 3%.

[0007] Furthermore, the mass ratio of the Sc element and the Er element is 1:1 to 2:1, and / or the reinforcing particles are selected from any one or more of TiC, SiC, B4C, ZrB2, TiB2, TiN, BN, SiO2 and Al2O3.

[0008] Furthermore, the texture of the heat-treatment-free ZL101A aluminum alloy includes primary aluminum, eutectic silicon, iron-containing phase and aluminum-scandium-erbium multi-phase, and the average grain size of the heat-treatment-free ZL101A aluminum alloy is 30 to 100 microns.

[0009] Furthermore, the heat treatment-free ZL101A aluminum alloy comprises Al3Sc phase and Al3(Sc, Er) phase, the mass content of the Al3Sc phase is 0.3% to 1%, and the mass ratio of the Al3Sc phase to the Al3(Sc, Er) phase is 1:2 to 2:1.

[0010] According to another aspect of the present invention, there is provided a method for preparing the aforementioned heat-treatment-free ZL101A aluminum alloy, the preparation method comprising: step S1, preparing the ingredients according to the composition of the alloy in claim 1, melting, insulating and refining the ingredients in sequence to obtain a refined melt; step S2, strengthening the refined melt with reinforcing particles to obtain a strengthened melt; step S3, modifying, refining and pouring the strengthened melt in sequence to obtain a heat-treatment-free ZL101A aluminum alloy.

[0011] Furthermore, in the above step S1, the melting temperature is 680-740°C; and / or the insulation temperature is 680-720°C, and the insulation time is 1-2h.

[0012] Furthermore, in the above step S1, a refining agent is added and argon is introduced during the refining process, the refining agent is hexachloroethane, and the mass proportion of hexachloroethane in the heat-treatment-free ZL101A aluminum alloy is 0.5% to 2%; and / or the argon is introduced for 10 to 40 minutes.

[0013] Furthermore, in the above step S2, the temperature of the alloy melt during the strengthening treatment is 750-800°C, and / or the insulation time of the alloy melt during the strengthening treatment is 10-60min; and / or the mass proportion of the reinforced particles in the heat-free ZL101A aluminum alloy is 0.1%-3%, and / or the particle size of the reinforced particles is 0.5μm-5μm.

[0014] Furthermore, in the above step S3, an intermediate alloy Al-10Sr is added during the modification process, and the mass proportion of the intermediate alloy Al-10Sr in the heat-free ZL101A aluminum alloy is 0.01% to 0.06%; and / or, an Al-5Ti-B refiner is added during the refinement process, and the insulation time is maintained for 10min to 30min, and the mass proportion of the Al-5Ti-B refiner in the heat-free ZL101A aluminum alloy is 0.1% to 2%.

[0015] Furthermore, in the above step S3, the pouring temperature is 680°C to 710°C.

[0016] Applying the technical solution of the present invention, the present application improves the mechanical properties of the heat-free ZL101A aluminum alloy by adding Sc elements, Er elements and TiN reinforcing particles in the heat-free ZL101A aluminum alloy, and improves the strength and toughness of the heat-free ZL101A aluminum alloy in the cast state. Specifically, on the one hand, due to the addition of Sc elements and Er elements, Al3Sc and Al3 (Sc, Er) reinforcing phases are generated in the casting, which can not only be used as nucleation particles to promote primary α-Al nucleation, but also hinder dislocation movement, thereby improving the yield strength and tensile strength of the alloy. On the other hand, the addition of reinforcing particles further improves the microstructure of the heat-free ZL101A aluminum alloy, improves the fine grain strengthening effect and dislocation strengthening effect of the heat-free ZL101A aluminum alloy, and the reinforcing particles as a part of the alloy can also bear the load when the alloy is loaded, further producing a strengthening effect. In addition, the addition of reinforcing particles will change the stress field of the surrounding matrix, which can promote the precipitation of the precipitated phase, and further improve the strength and toughness of the heat-free ZL101A alloy. Through the synergistic effect of the above two aspects, the heat-treatment-free ZL101A alloy obtains higher mechanical properties in the cast state. At the same time, under the premise of meeting the performance indicators, heat treatment is not required, thereby broadening the application range of the heat-treatment-free ZL101A aluminum alloy. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0018] Figure 1 The microstructure of the heat-free ZL101A aluminum alloy in the as-cast state in Example 1 of the present application is shown;

[0019] Figure 2 The stress-strain curve of the heat-treatment-free ZL101A aluminum alloy in the cast state in Example 1 of the present application is shown. DETAILED DESCRIPTION

[0020] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0021] As analyzed in the background technology of this application, there are problems in the prior art that the casting method of ZL101A aluminum alloy is difficult to avoid heat treatment and the mechanical properties of the obtained ZL101A aluminum alloy are poor. In order to solve the above problems, this application provides a heat treatment-free ZL101A aluminum alloy and a preparation method thereof.

[0022] In a typical embodiment of the present application, a heat-treatment-free ZL101A aluminum alloy is provided. The heat-treatment-free ZL101A aluminum alloy comprises, in terms of mass percentage, 6.5% to 7.5% Si element, 0.2% to 0.4% Mg element, 0.05% to 0.9% Sc element, 0.05% to 0.9% Er element, 0.1% to 0.2% Ti element, ≤0.1% Mn element, ≤0.2% Fe element, ≤0.2% Cu element, and the rest is Al element; wherein, the heat-treatment-free ZL101A aluminum alloy is further added with reinforcing particles, and the mass proportion of the reinforcing particles in the heat-treatment-free ZL101A aluminum alloy is 0.1%-3%.

[0023] The present application improves the mechanical properties of the heat-free ZL101A aluminum alloy by adding Sc elements, Er elements and TiN strengthening particles in the heat-free ZL101A aluminum alloy, and improves the strength and toughness of the heat-free ZL101A aluminum alloy in the cast state. Specifically, on the one hand, due to the addition of Sc elements and Er elements, Al3Sc and Al3 (Sc, Er) strengthening phases are produced in the casting, which can not only be used as nucleation particles to promote primary α-Al nucleation, but also hinder dislocation movement, thereby improving the yield strength and tensile strength of the alloy. On the other hand, the addition of strengthening particles further improves the microstructure of the heat-free ZL101A aluminum alloy, improves the fine grain strengthening effect and dislocation strengthening effect of the heat-free ZL101A aluminum alloy, and the strengthening particles can also bear the load when the alloy is loaded as a part of the alloy, further producing a strengthening effect, in addition, the addition of strengthening particles will change the stress field of the surrounding matrix, can promote the precipitation of the precipitated phase, and further improve the strength and toughness of the heat-free ZL101A alloy. Through the synergistic effect of the above two aspects, the heat-treatment-free ZL101A alloy obtains higher mechanical properties in the cast state. At the same time, under the premise of meeting the performance indicators, heat treatment is not required, thereby broadening the application range of the heat-treatment-free ZL101A aluminum alloy.

[0024] In one embodiment of the present application, the mass ratio of the Sc element to the Er element is 1:1 to 2:1, and / or the reinforcing particles are selected from any one or more of TiC, SiC, B4C, ZrB2, TiB2, TiN, BN, SiO2 and Al2O3.

[0025] It is preferred to control the mass ratio of Sc element and Er element within the above range, which is conducive to improving the synergistic effect of the two, thereby promoting the generation of Al3Sc and Al3(Sc, Er) strengthening phases in the casting, thereby promoting the nucleation of primary α-Al, and at the same time hindering dislocation movement, thereby improving the yield strength and tensile strength of the alloy. By controlling the type of reinforcing particles within the above range, the microstructure of the heat-free ZL101A aluminum alloy is improved, the fine grain strengthening effect and dislocation strengthening effect of the heat-free ZL101A aluminum alloy are improved, and at the same time, fine-tuning can be performed according to specific performance requirements, such as improving wear resistance, thermal stability or corrosion resistance, thereby broadening the application range of the heat-free ZL101A aluminum alloy.

[0026] In one embodiment of the present application, the texture of the heat-treatment-free ZL101A aluminum alloy includes primary aluminum, eutectic silicon, iron-containing phase and aluminum-scandium-erbium multiphase, and / or the average grain size of the heat-treatment-free ZL101A aluminum alloy is 30 to 100 microns.

[0027] It is preferred to control the texture types and volume percentages of different textures in the heat-treatment-free ZL101A aluminum alloy within the above range, which can achieve the optimization of the microstructure in the heat-treatment-free ZL101A aluminum alloy, thereby helping to improve the mechanical properties and processing properties of the heat-treatment-free ZL101A aluminum alloy. In addition, the presence of specific textures is conducive to improving the strength, plasticity and anisotropy of the heat-treatment-free ZL101A aluminum alloy, so that it has more balanced performance in different directions, thereby improving the application range of the heat-treatment-free ZL101A aluminum alloy. It is preferred to control the average grain size of the heat-treatment-free ZL101A aluminum alloy within the above range, which helps to further enhance the performance of the heat-treatment-free ZL101A aluminum alloy.

[0028] In one embodiment of the present application, the above-mentioned heat treatment-free ZL101A aluminum alloy includes Al3Sc phase and Al3(Sc, Er) phase, the mass content of Al3Sc phase is 0.3% to 1%, and the mass ratio of Al3Sc phase to Al3(Sc, Er) phase is 1:2 to 2:1.

[0029] It is preferred to control the mass of the Al3Sc phase and the mass ratio of the Al3Sc phase to the Al3(Sc, Er) phase within the above range, which is beneficial to promoting the nucleation of primary α-Al and hindering the dislocation movement, thereby improving the strengthening efficiency and plasticity of the heat-treatment-free ZL101A aluminum alloy, while also reducing the use of the Sc element and reducing costs.

[0030] In another typical embodiment of the present application, a method for preparing the above-mentioned heat treatment-free ZL101A aluminum alloy is provided, and the preparation method comprises: step S1, completing the ingredients according to the composition of the above-mentioned heat treatment-free ZL101A aluminum alloy, melting, insulating and refining the ingredients in sequence to obtain a refined melt; step S2, strengthening the refined melt with reinforcing particles to obtain a strengthened melt; step S3, metamorphosing, refining and pouring the strengthened melt in sequence to obtain a heat treatment-free ZL101A aluminum alloy.

[0031] The preparation method of the present application ensures that the heat-treatment-free ZL101A aluminum alloy material has excellent microstructure and mechanical properties by strictly controlling the conditions of melting, heat preservation, refining, adding reinforcing particles, modification and refinement, and pouring. By optimizing the entire process flow, especially through strengthening treatment and refinement treatment, the heat-treatment-free ZL101A aluminum alloy can achieve high strength and high toughness in the cast state, avoiding subsequent heat treatment, that is, avoiding the risk of deformation caused by subsequent heat treatment, and reducing manufacturing costs.

[0032] In one embodiment of the present application, in the above step S1, the melting temperature is 680-740° C.; and / or the insulation temperature is 680-720° C., and the insulation time is 1-2 hours.

[0033] It is preferred to control the melting temperature and the holding temperature within the above ranges to ensure good dissolution and uniform distribution of elements in the heat-free ZL101A aluminum alloy, and avoid volatilization of elements and degradation of material properties in the heat-free ZL101A aluminum alloy due to excessively high temperatures. At the same time, by controlling the holding time within the above range, the heat-free ZL101A aluminum alloy is kept in a molten state for a sufficiently long time, which is more conducive to promoting uniform diffusion of elements in the heat-free ZL101A aluminum alloy, and preventing oxidation and gas absorption problems caused by too long a holding time.

[0034] In one embodiment of the present application, in the above step S1, a refining agent is added and argon is introduced during the refining process, the refining agent is hexachloroethane, the mass proportion of hexachloroethane in the heat-treatment-free ZL101A aluminum alloy is 0.5% to 2%, and / or the argon is introduced for 10 to 40 minutes.

[0035] Hexachloroethane is mainly used for degassing and slag removal through chemical reactions during the refining process. It can wet and partially dissolve the oxides in suspension in the metal liquid during the refining process. As the bubbles rise, it has a good degassing and refining effect. Argon not only transmits hexachloroethane during the refining process, but also forms a stable gas protection layer to reduce the contact between the metal and the air and prevent the occurrence of oxidation reactions. In the present application, by controlling the mass of hexachloroethane within the above range, it is beneficial to remove the gas and inclusions in the alloy, thereby improving the purity of the alloy. By controlling the introduction time of argon within the above range, it is beneficial to ensure the refining effect and avoid excessive consumption of materials and waste of time.

[0036] In one embodiment of the present application, in the above step S2, the temperature of the alloy melt during the strengthening treatment is 750-800°C, and / or the insulation time of the alloy melt during the strengthening treatment is 10-60min; and / or the mass proportion of the reinforced particles in the heat-free ZL101A aluminum alloy is 0.1%-3%, and / or the particle size of the reinforced particles is 0.5μm-5μm.

[0037] It is preferred to control the conditions during the strengthening treatment within the above range, which is beneficial to improving the good bonding between the reinforcing particles and the alloy melt and improving the interface bonding strength of the composite material. At the same time, it is also beneficial to the uniform distribution of the reinforcing particles, reducing the risk of reinforcing particle agglomeration and formation of large particles, and improving the stability of the alloy performance.

[0038] In one embodiment of the present application, an intermediate alloy Al-10Sr is added during the above-mentioned modification process, and the mass proportion of the intermediate alloy Al-10Sr in the heat-free ZL101A aluminum alloy is 0.01% to 0.06%; and / or, an Al-5Ti-B refiner is added during the refinement process, and the mass proportion of the Al-5Ti-B refiner in the heat-free ZL101A aluminum alloy is 0.1% to 2%.

[0039] The present application adds the intermediate alloy Al-10Sr during the process of modification, which is beneficial to improve the eutectic structure of the heat-free ZL101A aluminum alloy, reduce the coarsening and splitting effect of the eutectic silicon phase, and improve the mechanical properties of the heat-free ZL101A aluminum alloy. By adding the Al-5Ti-B refiner during the refinement process, it is beneficial to promote the refinement of α-Al grains and improve the strength and plasticity of the heat-free ZL101A aluminum alloy. By controlling the ratio of the intermediate alloy Al-10Sr and the Al-5Ti-B refiner within the above range, it is beneficial to improve the full precipitation and refinement effect of Al3Sc and Al3 (Sc, Er) phases, thereby improving the comprehensive performance of the heat-free ZL101A aluminum alloy.

[0040] In one embodiment of the present application, in the above step S3, the pouring temperature is 680°C to 710°C.

[0041] It is preferred to control the pouring temperature within the above range, which is beneficial to improving the good filling of the heat-treated ZL101A aluminum alloy in the mold, reducing the risk of shrinkage cavities, cold shuts and pores, and is also beneficial to grain refinement and improving the dimensional accuracy and surface quality of the casting.

[0042] The beneficial effects of the present application will be further illustrated below in conjunction with embodiments.

[0043] Example 1

[0044] The ingredients are prepared according to the mass percentage of the elements in the heat-treatment-free ZL101A aluminum alloy, wherein the heat-treatment-free ZL101A aluminum alloy includes 6.5% Si element, 0.2% Mg element, 0.3% Sc element, 0.2% Er element, 0.1% Ti element, 0.005% Mn element, 0.02% Fe element, 0.005% Cu element, and the rest is Al element.

[0045] The preparation method comprises the following steps:

[0046] (1) Melting: The ingredients are prepared according to the above alloy composition design and melted at 720°C to obtain completely molten aluminum liquid;

[0047] (2) Insulation: Insulate the completely molten aluminum liquid at a temperature of 680°C for 1 hour;

[0048] (3) Refining: The aluminum liquid after heat preservation is refined by first adding 1% hexachloroethane (C2Cl6) for refining, and then passing argon gas through the melt for 30 minutes;

[0049] (4) Adding reinforcing particles: adjusting the melt temperature after refining to 800°C, adding reinforcing particles TiN to the refined melt for strengthening treatment, the mass of the reinforcing particles TiN added accounts for 0.5% of the mass of the ZL101A aluminum alloy batch, the particle size of the reinforcing particles TiN is 2 μm, and the holding time of the heat-free ZL101A aluminum alloy melt during the strengthening treatment is 40 min;

[0050] (5) Modification and refinement: adding 0.04% by weight of Al-10Sr master alloy in the heat-free ZL101A aluminum alloy and 0.5% by weight of Al-5Ti-B refiner in the heat-free ZL101A aluminum alloy to the melt in step (4);

[0051] (6) Pouring: The melt prepared in step (5) is poured into a mold at 700° C. to obtain a heat-treatment-free ZL101A aluminum alloy, the microstructure of which in the as-cast state is as follows: Figure 1 As shown in the figure, the stress-strain curve under cast state is as follows Figure 2 shown.

[0052] Example 2

[0053] The difference from Example 1 is that the ingredients are prepared according to the mass percentage of the elements in the heat-treatment-free ZL101A aluminum alloy, wherein the heat-treatment-free ZL101A aluminum alloy includes 7.5% Si element, 0.3% Mg element, 0.9% Sc element, 0.9% Er element, 0.2% Ti element, 0.08% Mn element, 0.08% Fe element, 0.18% Cu element, and the rest is Al element, and finally the heat-treatment-free ZL101A aluminum alloy is obtained.

[0054] Example 3

[0055] The difference from Example 1 is that the contents of Sc and Er are 0.33% and 0.17% respectively, and finally a heat-treatment-free ZL101A aluminum alloy is obtained.

[0056] Example 4

[0057] The difference from Example 1 is that the contents of Sc element and Er element are 0.25% and 0.25% respectively, and finally a heat treatment-free ZL101A aluminum alloy is obtained.

[0058] Example 5

[0059] The difference from Example 1 is that the reinforcing particles are TiB2, and finally a heat-treatment-free ZL101A aluminum alloy is obtained.

[0060] Example 6

[0061] The difference from Example 1 is that the mass of the reinforcing particles TiN accounts for 0.1% of the mass of the heat-treatment-free ZL101A aluminum alloy ingredients, and finally the heat-treatment-free ZL101A aluminum alloy is obtained.

[0062] Example 7

[0063] The difference from Example 1 is that the mass of the reinforcing particles TiN accounts for 3% of the mass of the heat-treatment-free ZL101A aluminum alloy ingredients, and finally the heat-treatment-free ZL101A aluminum alloy is obtained.

[0064] Example 8

[0065] The difference from Example 1 is that the melting temperature is 740° C., the holding temperature is 720° C., the holding time is 2 h, and finally the heat-treatment-free ZL101A aluminum alloy is obtained.

[0066] Example 9

[0067] The difference from Example 1 is that the mass proportion of hexachloroethane in the heat-treatment-free ZL101A aluminum alloy is 2%, the introduction time of argon gas is 40 minutes, and finally the heat-treatment-free ZL101A aluminum alloy is obtained.

[0068] Example 10

[0069] The difference from Example 1 is that (5) modification and refinement: adding 0.06% by mass of Al-10Sr master alloy in the heat-free ZL101A aluminum alloy and 2% by mass of Al-5Ti-B refiner in the heat-free ZL101A aluminum alloy to the melt in step (4);

[0070] (6) Pouring: The melt prepared in step (5) is poured into a mold at 680° C. to obtain a heat-treatment-free ZL101A aluminum alloy.

[0071] Comparative Example 1

[0072] The difference from Example 1 is that no reinforcing particles are added, and finally a heat-treatment-free ZL101A aluminum alloy is obtained.

[0073] Comparative Example 2

[0074] The difference from Example 1 is that the ingredients are prepared according to the mass percentage of the elements in the heat-treatment-free ZL101A aluminum alloy, wherein the heat-treatment-free ZL101A aluminum alloy includes 7.0% Si element, 0.2% Mg element, 0.01% Sc element, 0.01% Er element, 0.15% Ti element, 0.1% Mn element, 0.1% Fe element, 0.2% Cu element, and the rest is Al element, and finally the heat-treatment-free ZL101A aluminum alloy is obtained.

[0075] Comparative Example 3

[0076] The difference from Example 1 is that the ingredients are prepared according to the mass percentage of the elements in the heat-treatment-free ZL101A aluminum alloy, wherein the heat-treatment-free ZL101A aluminum alloy includes 7.0% Si element, 0.2% Mg element, 0.02% Sc element, 0.02% Er element, 0.15% Ti element, 0.1% Mn element, 0.1% Fe element, 0.2% Cu element, and the rest is Al element, and finally the heat-treatment-free ZL101A aluminum alloy is obtained.

[0077] The heat-treatment-free ZL101A aluminum alloys obtained in the above examples and comparative examples were subjected to the following performance tests, and the test results are listed in Table 1.

[0078] Test of average grain size of heat-treatment-free ZL101A aluminum alloy: GB / T 6394.

[0079] Test of texture of heat-treatment-free ZL101A aluminum alloy: GB / T 1173-2013.

[0080] Test of yield strength, tensile strength and elongation of ZL101A aluminum alloy without heat treatment at room temperature: GB / T228.1-2021. Test of mass content of Al3Sc phase and mass content of Al3(Sc, Er) phase: GB / T 20975.

[0081] Table 1

[0082]

[0083]

[0084] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0085] The present application improves the mechanical properties of the heat-free ZL101A aluminum alloy by adding Sc elements, Er elements and TiN strengthening particles in the heat-free ZL101A aluminum alloy, and improves the strength and toughness of the heat-free ZL101A aluminum alloy in the cast state. Specifically, on the one hand, due to the addition of Sc elements and Er elements, Al3Sc and Al3 (Sc, Er) strengthening phases are produced in the casting, which can not only be used as nucleation particles to promote primary α-Al nucleation, but also hinder dislocation movement, thereby improving the yield strength and tensile strength of the alloy. On the other hand, the addition of strengthening particles further improves the microstructure of the heat-free ZL101A aluminum alloy, improves the fine grain strengthening effect and dislocation strengthening effect of the heat-free ZL101A aluminum alloy, and the strengthening particles can also bear the load when the alloy is loaded as a part of the alloy, further producing a strengthening effect, in addition, the addition of strengthening particles will change the stress field of the surrounding matrix, can promote the precipitation of the precipitated phase, and further improve the strength and toughness of the heat-free ZL101A alloy. Through the synergistic effect of the above two aspects, the heat-treatment-free ZL101A alloy obtains higher mechanical properties in the cast state. At the same time, under the premise of meeting the performance indicators, heat treatment is not required, thereby broadening the application scope of the heat-treatment-free ZL101A aluminum alloy.

[0086] The above are only embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A heat-treatment-free ZL101A aluminum alloy, characterized in that: In terms of mass percentage, the heat-treatment-free ZL101A aluminum alloy includes: 6.5% to 7.5% of Si element, 0.2% to 0.4% of Mg element, 0.05% to 0.9% of Sc element, 0.05% to 0.9% of Er element, 0.1% to 0.2% of Ti element, ≤0.1% of Mn element, ≤0.2% of Fe element, ≤0.2% of Cu element, and the rest is Al element; wherein, reinforcing particles are also added to the heat-treatment-free ZL101A aluminum alloy, and the mass proportion of the reinforcing particles in the heat-treatment-free ZL101A aluminum alloy is 0.1% to 3%.

2. The heat treatment-free ZL101A aluminum alloy according to claim 1, characterized in that: The mass ratio of the Sc element to the Er element is 1:1 to 2:1, and / or the reinforcing particles are selected from any one or more of TiC, SiC, B4C, ZrB2, TiB2, TiN, BN, SiO2 and Al2O3.

3. The heat treatment-free ZL101A aluminum alloy according to claim 1 or 2, characterized in that: The texture of the heat-treatment-free ZL101A aluminum alloy includes primary aluminum, eutectic silicon, iron-containing phase and aluminum-scandium-erbium multi-phase, and / or the average grain size of the heat-treatment-free ZL101A aluminum alloy is 30 to 100 microns.

4. The heat-treatment-free ZL101A aluminum alloy according to any one of claims 1 to 3, characterized in that: The heat treatment-free ZL101A aluminum alloy comprises an Al3Sc phase and an Al3(Sc, Er) phase, the mass content of the Al3Sc phase is 0.3% to 1%, and the mass ratio of the Al3Sc phase to the Al3(Sc, Er) phase is 1:2 to 2:

1.

5. A method for preparing the heat-treatment-free ZL101A aluminum alloy according to any one of claims 1 to 4, characterized in that: The preparation method comprises: Step S1, preparing ingredients according to the alloy composition in claim 1, melting, keeping warm and refining the ingredients in sequence to obtain a refined melt; Step S2, strengthening the refined melt with strengthening particles to obtain a strengthened melt; Step S3, sequentially modifying, refining and pouring the strengthened melt to obtain the heat treatment-free ZL101A aluminum alloy.

6. The preparation method according to claim 5, characterized in that: In the step S1, the melting temperature is 680-740° C.; and / or the insulation temperature is 680-720° C., and the insulation time is 1-2 hours.

7. The preparation method according to claim 5 or 6, characterized in that: In the step S1, a refining agent is added and argon is introduced during the refining process, wherein the refining agent is hexachloroethane, and the mass proportion of hexachloroethane in the heat-treatment-free ZL101A aluminum alloy is 0.5% to 2%; and / or the argon is introduced for 10 to 40 minutes.

8. The preparation method according to any one of claims 5 to 7, characterized in that: In the step S2, the temperature of the alloy melt during the strengthening treatment is 750-800°C, and / or the insulation time of the alloy melt during the strengthening treatment is 10-60 min; and / or the mass proportion of the reinforced particles in the heat-treatment-free ZL101A aluminum alloy is 0.1%-3%, and / or the particle size of the reinforced particles is 0.5μm-5μm.

9. The preparation method according to any one of claims 5 to 8, characterized in that: In the step S3, an intermediate alloy Al-10Sr is added during the modification process, and the mass proportion of the intermediate alloy Al-10Sr in the heat-free ZL101A aluminum alloy is 0.01% to 0.06%; and / or, an Al-5Ti-B refiner is added during the refinement process, and the insulation time is maintained for 10 minutes to 30 minutes, and the mass proportion of the Al-5Ti-B refiner in the heat-free ZL101A aluminum alloy is 0.1% to 2%.

10. The preparation method according to any one of claims 5 to 9, characterized in that: In the step S3, the pouring temperature is 680°C to 710°C.

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