TiB₂ Particle Reinforced Heat-Resistant Aluminum Alloy Powder for Electron Beam Additive Manufacturing

Abstract

The present invention provides a titanium diboride particle-reinforced heat-resistant aluminum alloy powder for electron beam additive manufacturing. The chemical composition of the aluminum alloy powder includes, by mass percentage, Cu: 1.8-2.7%, Ni: 0.8-1.4%, Mg: 0-1.8%, Fe: 0.1-1.4%, TiB2 particles 0.1-10%, and the balance is aluminum. The main steps of its preparation method are: melting of the particle-reinforced aluminum alloy preform ingot and gas atomization forming of the particle-reinforced aluminum alloy powder. The block formed by electron beam additive manufacturing using the titanium diboride particle-reinforced heat-resistant aluminum alloy powder of the present invention has no cracks, and the microstructure is uniform and the grains are fine. After heat treatment, the obtained tensile strength is 320 MPa, and the elongation is greater than 10%, which is better than the average level of the mechanical properties of electron beam additive manufacturing aluminum alloys.

Description

Technical Field

[0001] The present invention belongs to the technical field of metal materials. Specifically, it relates to titanium diboride particle-reinforced heat-resistant aluminum alloy powder for electron beam additive manufacturing, and particularly to a particle-reinforced heat-resistant aluminum alloy powder for electron beam additive manufacturing and a preparation method thereof. Background Art

[0002] The additive manufacturing of aluminum alloys combines the advantages of material lightweight and rapid forming of complex-shaped components, and has great application prospects in key fields such as national defense, aerospace, and transportation. At present, the main technology used in the additive manufacturing of aluminum alloys is laser additive manufacturing. However, except for a few alloys such as Al-Si alloys, most aluminum alloys are prone to thermal cracking and porosity during laser additive manufacturing, and their printability is poor. In recent years, electron beam additive manufacturing technology has begun to be applied to aluminum alloys. Using an electron beam as an energy source, the pre-placed powder is heated by high-speed scanning under vacuum protection to achieve additive manufacturing. Compared with the laser energy source, using an electron beam has the advantages of high energy absorption rate; reducing oxidation and porosity, and high forming density; low residual stress, reducing print cracking, etc., which can solve the problem of poor printability of most aluminum alloys. Currently, it has been applied to the additive manufacturing of aluminum alloys such as AlSi10Mg and 2024. Nevertheless, the processing temperature during electron beam additive manufacturing is high (300 - 500 °C), resulting in the aluminum alloy being in a high-temperature thermal exposure state for a long time during the forming process, making the grain structure of the formed material coarse, with grain sizes in the tens to hundreds of micrometers, seriously affecting its mechanical properties. The tensile strength is usually lower than 300 MPa, showing a significant gap compared with the components formed by laser additive manufacturing; and there is obvious non-uniformity in the microstructure and strength along the printing height direction of the formed material due to different thermal exposure times. It is difficult to meet the service requirements. The reason for the above problems is that the eutectic phases (such as Si phase, Al-Cu phase) of the above aluminum alloys have poor heat resistance and coarsen under high-temperature thermal exposure. The coarsened eutectic phase cannot inhibit the growth of grains, resulting in coarse grains, thereby reducing the strength of the material. This severely restricts the application of aluminum alloys manufactured by electron beam additive manufacturing in industrial production. Therefore, it is of great significance to develop heat-resistant aluminum alloy powder suitable for electron beam additive manufacturing and obtain high-strength aluminum alloys manufactured by electron beam additive manufacturing. Summary of the Invention

[0003] To solve the above problems, the purpose of the present invention is to provide a titanium diboride particle-reinforced heat-resistant aluminum alloy powder for electron beam additive manufacturing.

[0004] The purpose of the present invention is achieved by the following technical solutions:

[0005] A titanium diboride particle-reinforced heat-resistant aluminum alloy powder, the chemical composition of the aluminum alloy powder includes, by mass percentage, Cu: 1.8 - 2.7%, Ni: 0.8 - 1.4%, Mg: 0 - 1.8%, Fe: 0.1 - 1.4%, TiB₂ particles 0.1 - 10%, and the balance is aluminum.

[0006] To further increase the content of the high-temperature strengthening phase Al9FeNi and reduce the hot cracking sensitivity of the alloy, preferably, by mass percentage, the content of Fe in the aluminum alloy powder is 0.3 - 0.9%, the content of Ni is 1.2 - 1.4%, and the content of Mg is 0 - 0.8%.

[0007] The preparation method of the titanium diboride particle-reinforced heat-resistant aluminum alloy powder comprises the following steps:

[0008] A. Select raw materials, calculate and weigh the amounts of various raw materials according to the predetermined alloy composition, and melt-cast the raw materials to obtain a preform ingot.

[0009] B. Prepare the titanium diboride particle-reinforced aluminum alloy powder by gas atomization of the alloy ingot or alloy rod.

[0010] The specific steps of step A are as follows:

[0011] A1. Melt Al, Al-TiB₂, Al-Cu master alloy, Al-Ni master alloy, and Al-Fe master alloy at 600°C - 1000°C, and then raise the temperature to 850 ± 5°C and hold for 15 - 30 min.

[0012] A2. Cool the melt to 680 ± 5°C, add Mg to the melt, and let it stand for 3 - 4 min to completely melt Mg.

[0013] A3. Raise the temperature of the melt to 760 ± 5°C, add a refining agent and refine for 5 - 10 min, and remove the surface scum; after refining, add a covering agent and degas in vacuum for 10 - 15 min, and remove the surface scum again. When the melt temperature is adjusted to 740 ± 5°C, cast and air-cool to obtain a preform ingot.

[0014] The refining agent in step A3 is selected from the JZJ type harmless aluminum alloy refining agent. Other commonly used refining agents in the energy field can also be used.

[0015] The covering agent in step A3 is selected from the JZF-03 type covering agent. Other commonly used covering agents in the energy field can also be used.

[0016] The specific steps of step B are as follows:

[0017] B1. Place the preform ingot into the melting chamber of the gas atomization equipment, and use nitrogen to displace the air in the melting chamber.

[0018] B2. Heat to 800°C to 1000°C to completely melt the preform ingot, and hold at the melting temperature for 5 min to 120 min;

[0019] B3. Let the melted preform ingot melt flow out from the nozzle of the gas atomization equipment, break into tiny droplets under the impact of high-speed nitrogen, and solidify into powder. After collection and vacuum packaging, the finished product of titanium diboride particle-reinforced aluminum alloy powder is obtained.

[0020] As another embodiment of the present invention, the powder preparation method includes the following steps:

[0021] (1) Add pure Al, high-purity Al-TiB2 master alloy, Al-Cu intermediate alloy block, Al-Ni intermediate alloy block, and Al-Fe intermediate alloy block into a crucible and place it in a resistance furnace for heating. Completely melt them at a melting temperature of 600 - 1000°C. Then hold at 850 ± 5°C for 15 min. After holding, remove the surface scum.

[0022] (2) Cool the melt to 680 ± 5°C, quickly press a pure Mg block into the melt with a graphite rod and let it stand for 3 min to completely melt the Mg block.

[0023] (3) Heat the melt to 760 ± 5°C, add a refining agent and refine for 5 min, then remove the surface scum. After refining, sprinkle a covering agent and conduct vacuum degassing for 10 min, then remove the surface scum again. When measuring the melt temperature at 740 ± 5°C, cast and air-cool to obtain a preform ingot.

[0024] (4) After placing the preform ingot obtained in step (3) into a crucible in the melting chamber of the gas atomization equipment, replace the air in the melting chamber with nitrogen;

[0025] (5) Through electromagnetic induction heating, completely melt the preform ingot and hold at the melting temperature for 5 min to 120 min to completely melt the ingot, and the melting temperature is 800°C to 1000°C;

[0026] (6) Let the melted preform ingot melt flow out from the nozzle, break into tiny droplets under the impact of high-speed nitrogen, and solidify into powder. After collection and vacuum packaging, the finished product of titanium diboride particle-reinforced aluminum alloy powder is obtained.

[0027] The present invention also provides an electron beam additive manufacturing method, and the manufacturing method includes the following steps:

[0028] Manufacture a block by additive manufacturing of the titanium diboride particle-reinforced aluminum alloy powder through an electron beam selective melting process.

[0029] The voltage used in electron beam additive manufacturing is 60 kV, the scanning beam current is 4.5 - 5.5 mA, the scanning speed is 0.8 - 1.6 m / s, the scanning mode is layer-by-layer scanning with a 90-degree rotation, and the TiB2 / Al-Cu-Mg-Fe-Ni bulk material is prepared.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) Based on the Al-Cu-Mg series heat-treatable aluminum alloy, and adding Fe and Ni alloying elements at the same time, the Al9FeNi high-temperature thermally stable phase is formed in the aluminum alloy, effectively suppressing the coarsening of the eutectic phase caused by high-temperature processing in electron beam additive manufacturing, thereby improving the heat resistance of the aluminum alloy matrix. And the strength of the printed and formed material can be further improved by subsequent heat treatment strengthening;

[0032] (2) The TiB2 particles introduced by in-situ melting are small in size, uniformly distributed, and tightly combined with the aluminum matrix, having a significant particle strengthening effect. And the TiB2 particles, as heterogeneous nucleating agents, refine the grains. On the one hand, it reduces the hot cracking sensitivity of the aluminum alloy during rapid solidification in additive manufacturing, improves the additive manufacturing formability of the aluminum alloy, and eliminates the anisotropy of the structure and properties. On the other hand, it achieves the effect of fine grain strengthening. At the same time, the TiB2 particles located at the grain boundaries and the thermally stable eutectic phases such as Al9FeNi jointly pin the grain boundaries, inhibiting the growth of grains under high-temperature processing conditions in electron beam additive manufacturing.

[0033] (3) The preparation method of the TiB2 / Al-Cu-Mg-Fe-Ni powder of the present invention is simple, the process is mature, Fe and Ni added are common alloying elements, the cost is low, and large-scale industrial production can be realized.

[0034] (4) The TiB2 / Al-Cu-Mg-Fe-Ni powder of the present invention can be used for electron beam additive manufacturing within a wide composition range and electron beam selective melting processing parameter window, and has good printing and forming performance. Description of the Drawings

[0035] By reading the detailed description of the non-limiting embodiments with reference to the following drawings, other features, purposes and advantages of the present invention will become more obvious:

[0036] Figure 1 Typical particle morphology and typical microstructure of the TiB2 / Al-Cu-Mg-Fe-Ni powder in Example 1;

[0037] Figure 2 Typical microstructure of the as-printed TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 1;

[0038] Figure 3Typical grain structure of as-built TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 1

[0039] Figure 4 Typical tensile curves of as-built TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 1 and heat-treated TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 2

[0040] Figure 5 Typical tensile curves of as-built TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 3 and heat-treated TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 4

[0041] Figure 6 Typical tensile curves of as-built TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 5 and heat-treated TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 6

[0042] Figure 7 Variation trend diagram of Al9FeNi phase fraction with Fe and Ni contents

[0043] Figure 8 Variation trend diagram of hot cracking sensitivity factor with Mg and Cu contents

[0044] Figure 9 Printed block samples of Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3 Detailed implementation manners

[0045] The present invention will be described in detail below with reference to the embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several adjustments and improvements can still be made. These all belong to the protection scope of the present invention.

[0046] Preparation of titanium diboride particle-reinforced heat-resistant aluminum alloy powder for electron beam additive manufacturing in Example 1

[0047] 1. Composition design

[0048] A alloy design strategy is proposed to increase the content of the Al9FeNi high-temperature strengthening phase while reducing the hot cracking sensitivity. Under the guidance of this strategy, a variation trend diagram of the Al9FeNi phase fraction with Fe and Ni contents ( Figure 7 ) and a variation trend diagram of the hot cracking sensitivity factor with Mg and Cu contents ( Figure 8), thereby optimizing the design to have a Fe content of 0.3 - 0.9 wt.%, a Ni content of 1.2 - 1.4 wt.%, and a Mg content of 0 - 0.8 wt.%.

[0049] 2. Preparation of Titanium Diboride Particle Reinforced Heat-Resistant Aluminum Alloy (TiB2 / Al-Cu-Mg-Fe-Ni) Powder

[0050] A titanium diboride particle reinforced heat-resistant aluminum alloy powder for electron beam additive manufacturing, wherein the chemical composition of the aluminum alloy in the powder is w(Cu)=2.60%, w(Ni)=1.12%, w(Mg)=1.60%, w(Fe)=0.63%, the mass fraction of TiB2 is 5.5 wt%, and the balance is aluminum.

[0051] The preparation method of the powder includes the following steps:

[0052] (1) Melting of TiB2 / Al-Cu-Mg-Fe-Ni Alloy Ingot:

[0053] a. Add pure Al, Al-TiB2 high-purity master alloy, Al-Cu intermediate alloy block, Al-Ni intermediate alloy block, and Al-Fe intermediate alloy block into a crucible and place it in a resistance furnace for heating. Completely melt it at a melting temperature of 800 °C. Then keep it warm at 850 °C for 15 min; after keeping warm, remove the surface scum.

[0054] b. Cool the melt to 680 °C, quickly press a pure Mg block into the melt with a graphite rod and let it stand for 3 min to completely melt the Mg block.

[0055] c. Heat the melt to 760 °C, add a refining agent and refine for 5 min, then remove the surface scum. After the refining is completed, sprinkle a covering agent and perform vacuum degassing for 10 min, then remove the surface scum again. When measuring the melt temperature at 740 °C, cast and air-cool to obtain an ingot.

[0056] (2) Gas Atomization Forming of TiB2 / Al-Cu-Mg-Fe-Ni Powder:

[0057] a. After putting the obtained TiB2 / Al-Cu-Mg-Fe-Ni ingot into the crucible in the melting chamber of the gas atomization equipment, replace the air in the melting chamber with nitrogen;

[0058] b. Through electromagnetic induction heating, the target temperature is 800 °C; keep it warm for 30 min to completely melt the ingot;

[0059] c. The melt flows out of the nozzle, flows along the nozzle under the action of gravity, and is broken into droplets of different sizes by the impact of rapidly moving atomizing nitrogen. The droplets solidify into powder during the falling process, and the falling powder is collected at the bottom of the cavity and vacuum packaged.

[0060] The typical morphology and typical microstructure of the TiB2 / Al-Cu-Mg-Fe-Ni powder prepared in this example are as Figure 1 shown; the powder particle size is 53 - 105 μm, and the sphericity is high. There are TiB2 particles in the powder.

[0061] 3. Electron beam additive manufacturing of TiB2 / Al-Cu-Mg-Fe-Ni bulk

[0062] Using the TiB2 / Al-Cu-Mg-Fe-Ni powder prepared in Step 1, a bulk is obtained by electron beam selective melting additive manufacturing. The acceleration voltage used in electron beam additive manufacturing is 60 kV, the scanning beam current size is 5.1 mA, the scanning speed is 1.4 m / s, and the scanning method is layer-by-layer scanning with a 90-degree rotation.

[0063] No cracks are generated in the prepared TiB2 / Al-Cu-Mg-Fe-Ni bulk, and the existence of a large number of pores is not observed. Its typical microscopic solidification structure is as Figure 2 shown, and TiB2 particles and eutectic phases are uniformly distributed throughout the printed bulk. The typical grain structure is as Figure 3 shown, the average grain size is less than 10 μm, which is 4 - 6 times smaller than the grain size of aluminum alloys manufactured by electron beam additive manufacturing in the industry. The as-printed TiB2 / Al-Cu-Mg-Fe-Ni bulk is uniaxially tensioned on a tensile testing machine (Zwick / Roell) according to the GB / T228.1-2010 standard using a -3 s -1 strain rate, and its tensile strength is measured to be 256 MPa, the yield strength is 135 MPa, and the elongation is 15.6%.

[0064] Example 2

[0065] The material composition in this example is the same as that in Example 1, and the powder preparation method is basically the same as that in Example 1.

[0066] The difference is that in experimental step 2, the as-printed TiB2 / Al-Cu-Mg-Fe-Ni bulk is solution-treated at 530 °C for 2 h, quenched in room temperature water at 25 °C, and then aged at 190 °C for 12 h. Its tensile strength is measured to be 320 MPa, the yield strength is 192 MPa, and the elongation is 11.3%.

[0067] Figure 4Typical tensile curves of the as-built TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 1 and the heat-treated TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 2;

[0068] Example 3

[0069] A titanium diboride particle-reinforced heat-resistant aluminum alloy powder for electron beam additive manufacturing, wherein the chemical composition of the aluminum alloy in the powder is w(Cu)=2.46%, w(Ni)=1.09%, w(Mg)=1.48%, w(Fe)=0.63%, the mass fraction of TiB2 is 4.6wt%, and the balance is aluminum.

[0070] The powder preparation method is basically the same as that in Example 1.

[0071] The difference is that: in experimental step 2, the scanning beam current used in electron beam additive manufacturing is 4.5 mA, and the scanning speed is 1 m / s. The measured tensile strength is 188 MPa, the yield strength is 85 MPa, and the elongation is 10.2%.

[0072] Example 4

[0073] The material composition in this example is the same as that in Example 3, and the powder preparation method is basically the same as that in Example 1.

[0074] The difference is that: in experimental step 2, the scanning beam current used in electron beam additive manufacturing is 4.5 mA, the scanning speed is 1 m / s, and the as-built TiB2 / Al-Cu-Mg-Fe-Ni block is solution-treated at 530 °C for 2 h, quenched in room temperature water at 25 °C, and then aged at 190 °C for 12 h. The measured tensile strength is 258 MPa, the yield strength is 130 MPa, and the elongation is 13.0%.

[0075] Figure 5 Typical tensile curves of the as-built TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 3 and the heat-treated TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 4.

[0076] Example 5

[0077] A titanium diboride particle-reinforced heat-resistant aluminum alloy powder for electron beam additive manufacturing, wherein the chemical composition of the aluminum alloy in the powder is w(Cu)=2.43%, w(Ni)=1.08%, w(Mg)=1.61%, w(Fe)=0.63%, the mass fraction of TiB2 is 4.9wt%, and the balance is aluminum.

[0078] The powder preparation method is basically the same as that in Example 1.

[0079] The difference lies in that: in experimental step 2, the scanning beam current used in electron beam additive manufacturing is 4.8 mA, and the scanning speed is 1.2 m / s. The measured tensile strength is 198 MPa, the yield strength is 97 MPa, and the elongation is 10.0%.

[0080] Example 6

[0081] This example has the same material composition as that described in Example 5, and the powder preparation method is basically the same as that of Example 1.

[0082] The difference lies in that: in experimental step 2, the scanning beam current used in electron beam additive manufacturing is 4.8 mA, the scanning speed is 1.2 m / s, and the as-printed TiB2 / Al-Cu-Mg-Fe-Ni bulk material is solution-treated at 530 °C for 2 h, quenched in room temperature water at 25 °C, and then aged at 190 °C for 12 h. The measured tensile strength is 287 MPa, the yield strength is 174 MPa, and the elongation is 13.8%.

[0083] Figure 6 are the typical tensile curves of the as-printed TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 5 and the heat-treated TiB2 / Al-Cu-Mg-Fe-Ni alloy in Example 6;

[0084] Example 7

[0085] A titanium diboride particle-reinforced heat-resistant aluminum alloy powder for electron beam additive manufacturing, wherein the chemical composition of the aluminum alloy powder is w(Cu)=1.86%, w(Ni)=1.25%, w(Mg)=0.78%, w(Fe)=0.88%, the mass fraction of TiB2 is 1 wt%, and the balance is aluminum.

[0086] The powder preparation method is basically the same as that of Example 1. The measured tensile strength in the as-printed state is 242 MPa, the yield strength is 115 MPa, and the elongation is 18.2%.

[0087] Example 8

[0088] The difference from Example 7 is that the chemical composition of the aluminum alloy powder is w(Cu)=2.30%, w(Ni)=1.36%, w(Mg)=0.5%, w(Fe)=0.78%, the mass fraction of TiB2 is 0.1 wt%, and the balance is aluminum.

[0089] The measured tensile strength in the as-printed state is 238 MPa, the yield strength is 109 MPa, and the elongation is 19.0%.

[0090] Example 9

[0091] It is different from Example 7 in that the chemical composition of the aluminum alloy powder is w(Cu)=1.81%, w(Ni)=1.21%, w(Mg)=0.3%, w(Fe)=0.35%, the mass fraction of TiB2 is 9.5 wt%, and the balance is aluminum.

[0092] The experimental steps 1 and 2 are the same as those in Example 1. The measured tensile strength of the as-printed state is 268 MPa, the yield strength is 144 MPa, and the elongation is 7.5%.

[0093] Comparative Example 1

[0094] The difference between Comparative Example 1 and Example 1 is that TiB2 is not added to the alloy components.

[0095] The chemical composition of the aluminum alloy in the powder is w(Cu)=2.62%, w(Ni)=1.12%, w(Mg)=1.68%, w(Fe)=0.63%, but TiB2 is not added, and the balance is aluminum.

[0096] Due to the lack of TiB2 particles for grain refinement, a large number of holes and depressions appear in the electron beam additive manufacturing formed samples, and it is impossible to print out formed bulk samples.

[0097] Comparative Example 2

[0098] This comparative example has the same alloy composition as that described in Example 1, and the powder preparation method is basically the same as that in Example 1.

[0099] The difference is that: in experimental step 2, the scanning beam current used in electron beam additive manufacturing is 5.9 mA, which is greater than the scanning beam current value within the protection scope of this application, and serious bulging appears on the surface of the printed bulk sample, and precise 3D printing forming cannot be achieved.

[0100] Comparative Example 3

[0101] This comparative example has the same material composition as that described in Example 1, and the powder preparation method is basically the same as that in Example 1.

[0102] The difference is that: in experimental step 2, the scanning beam current used in electron beam additive manufacturing is 3.6 mA, which is less than the scanning beam current value within the protection scope of this application, and obvious depression appears on the surface of the printed bulk sample, and precise 3D printing forming cannot be achieved.

[0103] Figure 9 Diagrams of the printed bulk samples in Example 1, Comparative Example 1, Comparative Example 2, and Comparative Example 3.

[0104] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various deformations or modifications within the scope of the claims, which does not affect the essence of the present invention.

Claims

1. An electron beam additive manufacturing method, characterized in that, The preparation method includes the following steps: Additively manufacture a block by electron beam selective melting process using titanium diboride particle reinforced aluminum alloy powder; Including Cu: 1.86%, Ni: 1.25%, Mg: 0.78%, Fe: 0.88%, TiB2 particles 1%, and the balance is aluminum; Or, including Cu: 2.30%, Ni: 1.36%, Mg: 0.5%, Fe: 0.788%, TiB2 particles 0.1%, and the balance is aluminum; The voltage used in electron beam additive manufacturing is 60 kV, the scanning beam current is 4.5 - 5.5 mA, the scanning speed is 0.8 - 1.6 m / s, and the scanning method is layer-by-layer scanning with a 90-degree rotation to prepare TiB2 / Al-Cu-Mg-Fe-Ni blocks.

2. The preparation method according to claim 1, characterized in that, The preparation method of the titanium diboride particle reinforced aluminum alloy powder includes the following steps: A. Select raw materials, calculate and weigh the amounts of various raw materials according to the predetermined alloy composition, and melt-cast the raw materials to obtain a preform ingot; B. Prepare the titanium diboride particle reinforced aluminum alloy powder by gas atomization of the preform ingot.

3. The preparation method according to claim 2, characterized in that, characterized in that, The specific steps of step A include the following steps: A1. Melt Al, Al-TiB2, Al-Cu master alloy, Al-Ni master alloy, and Al-Fe master alloy at 600 °C - 1000 °C, and then heat up to 850 ± 5 °C and hold for 15 - 30 min; A2. Cool the melt to 680 ± 5 °C, add Mg to the melt and let it stand for 3 - 4 min to completely melt Mg; A3. Heat the melt to 760 ± 5 °C, add a refining agent and refine for 5 - 10 min, and remove the surface scum; after refining, add a covering agent and degas under vacuum for 10 - 15 min, and remove the surface scum again. When the melt temperature is adjusted to 740 ± 5 °C, cast and air-cool to obtain a preform ingot.

4. The preparation method according to claim 3, characterized in that, The refining agent in step A3 is selected from JZJ type harmless aluminum alloy refining agent.

5. The preparation method according to claim 3, characterized in that, The covering agent in step A3 is selected from JZF-03 type covering agent.

6. The preparation method according to claim 2, characterized in that, The specific steps of step B include the following steps: B1. Place the preform ingot into the melting chamber of the gas atomization equipment, and use nitrogen to displace the air in the melting chamber; B2. Heat to 800 °C - 1000 °C to completely melt the preform ingot, and hold at the melting temperature for 5 min - 120 min; B3. Let the melted preform ingot melt flow out from the nozzle of the gas atomization equipment, break into tiny droplets under the impact of high-speed nitrogen, and solidify into powder. After collection and vacuum packaging, the finished product of titanium diboride particle reinforced aluminum alloy powder is obtained.

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