A method for producing an aluminum-silicon alloy forging

Abstract

The application provides a preparation method of high-performance aluminum-silicon alloy forgings, comprising the following steps: high-energy ball milling of aluminum powder and silicon powder to obtain high-activity ultra-fine aluminum-silicon mixed powder; isostatic pressing of the obtained mixed powder to obtain a preform; preheating of the preform and then forging sintering to obtain high-performance aluminum-silicon alloy forgings. The application completes the rapid sintering of high-activity ultra-fine aluminum-silicon alloy powder under pressure, the deformation, flow and mold filling process of metal fluid, and simultaneously realizes the sintering of the powder and the forging deformation of the sintered body, so that high-density and high-mechanical-property aluminum-silicon alloy forgings are finally obtained.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of aluminum-silicon alloy, and particularly relates to a preparation method of high-performance aluminum-silicon alloy forgings. BACKGROUND

[0002] Aluminum-silicon alloy is a kind of aluminum alloy with aluminum and silicon as main components, and generally contains about 12.6 wt.% of silicon, a small amount of magnesium and copper as reinforcing components. The aluminum-silicon alloy has the advantages of light weight, good heat conduction performance, low expansion coefficient, certain strength, hardness and corrosion resistance, and has become one of the materials for heat-resistant and wear-resistant components such as engine pistons.

[0003] Casting is the main method for preparing aluminum-silicon alloy, and is also the method for preparing the most varieties of aluminum-silicon alloy with the widest application. Since the aluminum-silicon alloy is a typical eutectic alloy, only when the aluminum-silicon eutectic point (the silicon content is 12.6 wt.%) is reached, the cast aluminum-silicon alloy has a relatively fine eutectic structure and ideal mechanical properties. When the hypoeutectic composition (the silicon content is less than 12.6 wt.%), the cast aluminum-silicon alloy has coarse α(Al) phase structure inside; when the hypereutectic composition (the silicon content is greater than 12.6 wt.%), the cast aluminum-silicon alloy has coarse β(Si) phase structure inside, and the coarse α(Al) and β(Si) will significantly reduce the mechanical properties. Therefore, when preparing the cast aluminum-silicon alloy, the silicon content is limited in a very small range of about 12.6 wt.%, and grain refiners and modifiers need to be added during preparation to significantly refine and modify the microstructure, so as to obtain ideal mechanical properties.

[0004] The rapid solidification powder metallurgy process is an advanced method for preparing aluminum-silicon alloy. In the process of rapid cooling of alloy from high-temperature liquid phase to solid phase (quenching rate 100 K / s), many physical transport phenomena are inhibited, so that the solidification of aluminum-silicon alloy deviates from the equilibrium phase diagram, and micron and submicron fine microstructure is obtained, so that the aluminum-silicon alloy has excellent mechanical properties. The rapid solidification powder metallurgy process has a significant advantage, especially in the preparation of hypereutectic composition alloy. However, the high preparation cost limits the wide application of the technology.

[0005] How to optimize the preparation method to obtain high-performance aluminum-silicon alloy has become a hot spot in the field. SUMMARY

[0006] Therefore, the purpose of the present application is to provide a preparation method of high-performance aluminum-silicon alloy forgings. The aluminum-silicon alloy forgings prepared by the method have good performance.

[0007] The present application provides a preparation method of high-performance aluminum-silicon alloy forgings, comprising:

[0008] The aluminum powder and the silicon powder are subjected to high-energy ball milling to obtain a mixed powder;

[0009] The mixed powder is subjected to isostatic pressing to obtain a preform;

[0010] The preform is subjected to preheating and then to forging sintering to obtain a high-performance aluminum-silicon alloy forging.

[0011] In the embodiments of the present application, the mixed powder can be an ultrafine and high-activity mixed powder; the average grain size of the mixed powder can be selected from 180-400 nm, such as 200 nm, 250 nm, 300 nm, 350 nm; the time of high-energy ball milling can be selected from 28-35 h, such as 30 h, 32 h; a control agent can be added during the high-energy ball milling, the control agent can be selected from ethanol; the control agent also includes acetone; the volume ratio of ethanol and acetone can be selected from (0.8-1.2):1, such as 1:1; the amount of the control agent added can be selected from 28-48 microliters of the control agent per gram of the mixed powder, such as 30 microliters, 32 microliters, 35 microliters, 40 microliters, 45 microliters; the ball-to-material ratio during the high-energy ball milling can be selected from (10-12):1, such as 11:1.

[0012] In the embodiments of the present application, the components of the mixed powder can be:

[0013] 12-25 wt% of silicon;

[0014] The balance is aluminum.

[0015] In the embodiments of the present application, the mass content of silicon can be selected from 15%, 18%, 20%, 22%.

[0016] In the embodiments of the present application, the isostatic pressing can be cold isostatic pressing; the pressure of the isostatic pressing can be selected from 200-300 MPa, such as 210 MPa, 230 MPa, 240 MPa, 250 MPa, 270 MPa; the time of the isostatic pressing can be selected from 2-5 min, such as 3 min, 4 min.

[0017] In the embodiments of the present application, the density of the preform can be selected from 65-75%, such as 68%, 70%, 72%.

[0018] In the embodiments of the present application, the temperature of the preheating can be selected from 600-640℃, such as 610℃, 620℃, 630℃; the time of the preheating can be selected from 2-5 min, such as 3 min, 4 min.

[0019] In the embodiments of the present application, the forging sintering can be performed in a forging die; the temperature of the forging die during the forging sintering can be selected from 320-360℃, such as 330℃, 340℃, 350℃.

[0020] In the embodiments of the present application, the method for forging sintering can comprise:

[0021] The first-stage pressing is followed by the second-stage pressing.

[0022] In the embodiments of the present application, the temperature for forging sintering is consistent with the temperature of the forging die described in the above technical solution; the first-stage pressing is preliminary forging, and the second-stage pressing is finish forging.

[0023] In the embodiments of the present application, the speed of the first-stage pressing can be selected from 0.5-0.6 mm, such as 0.55 mm; the pressure of the first-stage pressing can be selected from 150-250 tons, such as 180-220 tons, 200 tons; and the forging pressure ratio of the first-stage pressing can be selected from (1-3):1, such as (1.5-2.5):1, (1.8-2.2):1, 2:1.

[0024] In the embodiments of the present application, the first-stage pressing is switched to the second-stage pressing when the cross-sectional area of the forged piece obtained by the first-stage pressing reaches 1.8-2.2 times, such as 2 times, of the cross-sectional area of the pre-obtained forged piece.

[0025] In the embodiments of the present application, the speed of the second-stage pressing can be selected from 10-12 mm / s, such as 11 mm / s; the pressure of the second-stage pressing can be selected from 200-300 tons, such as 220-205 tons, 240 tons; and the forging pressure ratio of the second-stage pressing can be selected from (1-1.5):1, such as 1.2:1.

[0026] In the embodiments of the present application, the sintering forging technology can obtain a supersaturated solid solution structure and a fine, little-segregation or non-segregation microstructure similar to a rapid solidification state. However, due to the serious oxidation phenomenon in the preparation process of aluminum-silicon alloy, the sintering forging technology has not been reported to be applied in aluminum-silicon alloy, especially in aluminum-silicon alloy. The sintering forging technology can obtain a microstructure similar to a rapid solidification state. After the sintering forging process is optimized and applied in the preparation of hypereutectic aluminum-silicon alloy, the alloy performance (strength, high-temperature resistance, heat resistance, wear resistance, etc.) can be greatly improved, which has important significance for promoting the large-scale application and industrialization of aluminum-silicon forgings.

[0027] The present application adopts sintering forging process to prepare high-performance aluminum-silicon alloy forgings. First, superfine aluminum-silicon alloy powder with clean surface and high activity is prepared; then, rapid sintering and forging of the superfine aluminum-silicon alloy powder is realized through sintering forging technology. The present application adopts high-energy ball milling technology to prepare superfine aluminum-silicon alloy powder with clean surface and high activity by adjusting ball milling powder preparation process and process control agent. Due to the effect of the process control agent, the activity and cleanliness of the superfine aluminum-silicon alloy powder surface can be temporarily protected, which solves the technical problems of preparation, storage and transportation of superfine and high-activity aluminum-silicon alloy powder in air environment, and provides basic conditions for the next step of rapid sintering and forging deformation. The present application realizes rapid sintering of the superfine aluminum-silicon alloy powder under pressure, metal fluid deformation, flow and mold filling process through sintering forging technology, synchronously realizes powder sintering and sintering body forging deformation, and finally obtains aluminum-silicon alloy forgings with high density and high mechanical properties. The process is simple and efficient, as shown in Figure 2

[0028] In the prior art, powder forging products must be pre-sintered for a long time before subsequent forging, and the process is relatively complicated, as shown in Figure 1 The present application realizes preparation of high-activity and superfine aluminum-silicon alloy powder through high-energy ball milling technology, and obtains aluminum-silicon alloy forgings with high mechanical properties through sintering forging technology. BRIEF DESCRIPTION OF DRAWINGS

[0029] Figure 1 The process flow chart of powder forging in the prior art is shown in

[0030] Figure 2 The process flow chart of sintering forging in the embodiment of the present application is shown in

[0031] Figure 3 The cross-sectional SEM image of the aluminum-silicon forging prepared in Example 1 of the present application is shown in

[0032] Figure 4 is the cross-sectional SEM image of the aluminum body of the aluminum-silicon forging prepared in Example 1 of the present application. DETAILED DESCRIPTION

[0033] The technical solutions in the embodiments of the present application will be described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0034] Example 1

[0035] ​Put 250 g of mixed powder into a ball mill tank, wherein the silicon powder accounts for 12 wt.%, the aluminum powder accounts for 88 wt.%, the ball-to-material ratio is 10:1, add 12 ml of ethanol as a process control agent, and after high-energy ball milling for 35 hours, high-activity powder is obtained;

[0036] Cold isostatic pressing is performed on the high-activity powder, the pressure is 220 MPa, and the pressure holding time is 2 minutes, to obtain a preform;

[0037] The preform is preheated in a high-temperature furnace, the preheating temperature is 600℃, and the preheating time is 5 minutes. The preform is taken out and placed in a 320℃ forging die for forging sintering. One-stage pressing and two-stage pressing are performed in turn. The one-stage pressing speed is 0.5 mm / s; the pressure is 200 tons; the forging pressure ratio is 2:1. When the cross-sectional area of the forged product after one-stage pressing is 2 times the cross-sectional area of the pre-obtained forged product, two-stage pressing is performed. The two-stage pressing speed is 10 mm / s; the pressure is 250 tons; the forging pressure ratio is 1.2:1, and the forged product is obtained.

[0038] The forged product prepared in Example 1 is sampled, polished, and tested. The performance of the forged product is shown in Table 1, the microstructure is shown in Figure 3 and Figure 4 , Figure 3 which is a microstructure diagram of the fracture of the aluminum-silicon forged product after forging sintering. It can be seen that the silicon particles are uniformly distributed, and the average particle size is less than 20 microns; Figure 4 which is a microstructure diagram of the cross section of the matrix aluminum in the aluminum-silicon forged product. It can be seen that there are fine structures smaller than 1 micron inside the matrix aluminum.

[0039] The product prepared in Example 1 is sampled, polished, and tested. The tensile test is tested according to GB / T 228.1-2010 "Metallic Materials Tensile Test Part 1: Room Temperature Test Method", the hardness test is tested according to GB231-84 "Metallic Brinell Hardness Test Method", the tensile-compressive fatigue strength test is tested according to GB / T 3075-2021 "Metallic Material Fatigue Test Axial Force Control Method", and the test results are shown in Table 1.

[0040] Example 2

[0041] Put 250 g of mixed powder into a ball mill tank, wherein the silicon powder accounts for 12 wt.%, the aluminum powder accounts for 88 wt.%, the ball-to-material ratio is 10:1, add 12 ml of ethanol as a process control agent, and after high-energy ball milling for 35 hours, high-activity powder is obtained;

[0042] Cold isostatic pressing is performed on the high-activity powder, the pressure is 220 MPa, and the pressure holding time is 2 minutes, to obtain a preform;

[0043] The preform is preheated in a high-temperature furnace, the preheating temperature is 630℃, the preheating time is 3 minutes, the preform is taken out and placed in a forging die of 330℃, the preform is powder forged and sintered, one-stage pressing and two-stage pressing are sequentially performed, the one-stage pressing speed is 0.6 mm / s; the pressure is 200 tons; the forging pressure ratio is 2:1; when the cross-sectional area of the forged product obtained by one-stage pressing is twice the cross-sectional area of the pre-obtained forged product, two-stage pressing is performed, the two-stage pressing speed is 10 mm / s; the pressure is 240 tons; the forging pressure ratio is 1.2:1, and the forged product is obtained.

[0044] According to the method of Example 1, the performance of the forged product prepared in Example 2 is detected, and the detection results are shown in Table 1.

[0045] Example 3

[0046] 250g of mixed powder is placed in a ball milling tank, wherein the silicon powder accounts for 18 wt.%, the aluminum powder accounts for 82 wt.%, the ball-to-material ratio is 10:1, 8ml of ethanol is added as a process control agent, and after high-energy ball milling for 30 hours, high-activity powder is obtained;

[0047] The high-activity powder is cold isostatic pressed to obtain a preform, the pressure is 240 MPa, and the pressure holding time is 3 minutes.

[0048] The preform is preheated in a high-temperature furnace, the preheating temperature is 640℃, the preheating time is 4 minutes, the preform is taken out and placed in a forging die of 340℃, the preform is powder forged and sintered, one-stage pressing and two-stage pressing are sequentially performed, the one-stage pressing speed is 0.5 mm / s; the pressure is 200 tons; the forging pressure ratio is 2:1; when the cross-sectional area of the forged product obtained by one-stage pressing is twice the cross-sectional area of the pre-obtained forged product, two-stage pressing is performed, the two-stage pressing speed is 12 mm / s; the pressure is 240 tons; the forging pressure ratio is 1.2:1, and the forged product is obtained.

[0049] According to the method of Example 1, the performance of the forged product prepared in Example 3 is detected, and the detection results are shown in Table 1.

[0050] Example 4

[0051] 250g of mixed powder is placed in a ball milling tank, wherein the silicon powder accounts for 20 wt.%, the aluminum powder accounts for 80 wt.%, the ball-to-material ratio is 10:1, 7ml of ethanol is added as a process control agent, and after high-energy ball milling for 28 hours, high-activity powder is obtained;

[0052] The high-activity powder is cold isostatic pressed to obtain a preform, the pressure is 250 MPa, and the pressure holding time is 3 minutes.

[0053] The preform is preheated in a high-temperature furnace, the preheating temperature is 640℃, the preheating time is 2 minutes, the preform is taken out and placed in a forging die at 350℃, the preform is powder forged and sintered, one-stage pressing and two-stage pressing are sequentially performed, the one-stage pressing speed is 0.5 mm / s; the pressure is 200 tons; the forging pressure ratio is 2:1; the one-stage pressing is performed to 2 times of the cross-sectional area of the pre-obtained forging, the two-stage pressing is performed, the two-stage pressing speed is 11 mm / s; the pressure is 240 tons; the forging pressure ratio is 1.2:1, and the forging product is obtained.

[0054] According to the method of Example 1, the performance of the forging product prepared in Example 4 is detected, and the detection results are shown in Table 1.

[0055] Example 5

[0056] 250g of mixed powder is placed in a ball milling tank, wherein the silicon powder accounts for 25 wt.%, the aluminum powder accounts for 75 wt.%, the ball-to-material ratio is 12:1, 4ml of ethanol and 4ml of acetone are added as process control agents, and after high-energy ball milling for 28 hours, high-activity powder is obtained;

[0057] The high-activity powder is cold isostatic pressed to obtain a preform, the pressure is 250 MPa, and the pressure holding time is 3 minutes;

[0058] The preform is preheated in a high-temperature furnace, the preheating temperature is 640℃, the preheating time is 5 minutes, the preform is taken out and placed in a forging die at 360℃, the preform is powder forged and sintered, one-stage pressing and two-stage pressing are sequentially performed, the one-stage pressing speed is 0.5 mm / s; the pressure is 200 tons; the forging pressure ratio is 2:1; the one-stage pressing is performed to 2 times of the cross-sectional area of the pre-obtained forging, the two-stage pressing is performed, the two-stage pressing speed is 10 mm / s; the pressure is 230 tons; the forging pressure ratio is 1.2:1, and the forging product is obtained.

[0059] According to the method of Example 1, the performance of the forging product prepared in Example 5 is detected, and the detection results are shown in Table 1.

[0060] Example 6

[0061] 250g of mixed powder is placed in a ball milling tank, wherein the silicon powder accounts for 25 wt.%, the aluminum powder accounts for 75 wt.%, the ball-to-material ratio is 12:1, 4ml of ethanol and 4ml of acetone are added as process control agents, and after high-energy ball milling for 28 hours, high-activity powder is obtained;

[0062] The high-activity powder is cold isostatic pressed to obtain a preform, the pressure is 250 MPa, and the pressure holding time is 3 minutes;

[0063] The preform is preheated in a high-temperature furnace, the preheating temperature is 600℃, the preheating time is 3 minutes, the preform is taken out and put into a forging die at 340℃, the preform is powder forged and sintered, one-stage pressing and two-stage pressing are sequentially performed, the one-stage pressing speed is 0.5mm / s; the pressure is 200 tons; the forging pressure ratio is 2:1; when the cross-sectional area of the forged product is 2 times the cross-sectional area of the pre-obtained forged product, two-stage pressing is performed, the two-stage pressing speed is 10mm / s; the pressure is 250 tons; the forging pressure ratio is 1.2:1, and the forged product is obtained.

[0064] The performance of the forged product prepared in Example 6 is detected according to the method of Example 1, and the detection results are shown in Table 1.

[0065] Example 7

[0066] 250g of mixed powder is put into a ball milling tank, wherein the silicon powder accounts for 15 wt.%, the aluminum powder accounts for 85 wt.%, the ball-to-material ratio is 12:1, 10ml of ethanol is added as a process control agent, and high-energy ball milling is performed for 50 hours to obtain high-activity powder;

[0067] The high-activity powder is cold isostatic pressed to obtain a preform, and the pressure is 230MPa and the pressure holding time is 2 minutes;

[0068] The preform is preheated in a high-temperature furnace, the preheating temperature is 630℃, the preheating time is 3 minutes, the preform is taken out and put into a forging die at 330℃, the preform is powder forged and sintered, one-stage pressing and two-stage pressing are sequentially performed, the one-stage pressing speed is 0.5mm / s; the pressure is 200 tons; the forging pressure ratio is 2:1; when the cross-sectional area of the forged product is 2 times the cross-sectional area of the pre-obtained forged product, two-stage pressing is performed, the two-stage pressing speed is 10mm / s; the pressure is 240 tons; the forging pressure ratio is 1.2:1, and the forged product is obtained.

[0069] The performance of the forged product prepared in Example 7 is detected according to the method of Example 1, and the detection results are shown in Table 1.

[0070] Example 8

[0071] 250g of mixed powder is put into a ball milling tank, wherein the silicon powder accounts for 20 wt.%, the aluminum powder accounts for 80 wt.%, the ball-to-material ratio is 12:1, 7ml of ethanol is added as a process control agent, and high-energy ball milling is performed for 38 hours to obtain high-activity powder;

[0072] The high-activity powder is cold isostatic pressed to obtain a preform, and the pressure is 240MPa and the pressure holding time is 3 minutes;

[0073] The preform is preheated in a high-temperature furnace, the preheating temperature is 500 DEG C, the preheating time is 3 minutes, the preform is taken out and put into a 340 DEG C forging die, the preform is powder forged and sintered, one-stage pressing and second-stage pressing are carried out in turn, the one-stage pressing speed is 0.5 mm / s, the pressure is 100 tons, the forging pressure ratio is 2:1, when the cross-sectional area of the forging part is 2 times the cross-sectional area of the pre-obtained forging part, the second-stage pressing is carried out, the second-stage pressing speed is 10 mm / s, the pressure is 120 tons, and the forging pressure ratio is 1.2:1, thereby obtaining the forging product.

[0074] According to the method of example 1, the performance of the forging product prepared in example 8 is detected, and the detection results are shown in table 1.

[0075] Table 1: performance detection results of the silicon-aluminum alloy forging product prepared in example

[0076] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Tensile strength (MPa) 473 482 492 505 496 221 241 258 Hardness (HB) 162 160 161 160 162 68 70 67 10 7 Tensile fatigue strength (MPa) 95 95 80 85 80 47 43 44 High temperature strength (350°C) (MPa) 210 215 215 216 215 90 92 92

[0077] As shown in table 1, examples 1-5 add process control agents in the preparation process, and the high-energy ball milling time, the forging sintering temperature and the pressure are controlled, so that the key mechanical properties such as the tensile strength and the hardness of the prepared product are very excellent. In example 6, the process control agent is added improperly, the mechanical alloying degree of the powder in the ball milling process is poor, which leads to a large decline in the mechanical properties. In example 7, the high-energy ball milling time is not properly controlled, which leads to excessive forging of the powder, the powder particles grow up too early, and the mechanical properties decline significantly. In example 8, the sintering temperature and the pressure are not properly controlled, which leads to poor microstructure combination and poor density of the powder, and the mechanical properties are greatly reduced. In addition, through experimental research, it is found that the key parameters (the amount of the control agent, the ball milling time, the temperature and the pressure of the forging sintering) in the application can significantly improve the key mechanical properties of Al-Si alloys with different component contents, and the method provided by the application has universality in the Al-Si alloy system and has great potential and value.

[0078] The application adopts a one-step process of "forging sintering" under pressure to replace the multi-step process in the existing powder forging process, as shown in Figure 1 and Figure 2 Compared with the prior art, the application utilizes the high-energy dry ball milling process, and under the collision action of the high-energy grinding ball medium, the aluminum and silicon ComponentThe repeated cold welding and breaking between the powders form refined composite particles, and the gaseous molecules of the added process control agent are wrapped on the surface of the superfine and high-activity powders to play the role of blocking oxygen and protecting the surface activity; then the powders are press-formed by isostatic pressing to obtain a uniform compact with a density of about 70%; then the compact is preheated to release the gas wrapped on the surface of the particles and expose the superfine and high-activity surface again; then the powders with high-activity surface in the compact are rapidly sintered by pressure sintering and forging process to realize effective bonding between the particles, and finally the forged piece with a specific shape is formed through the solute deformation, flow and mold filling process, so that the aluminum-silicon alloy forged piece with fine and uniform microstructure is prepared, thereby the strength and high-temperature resistance of the forged piece are significantly improved.

[0079] The preparation method provided by the application can realize rapid sintering and forging deformation under pressure simultaneously, and the high mechanical properties of the forged piece can be realized without separate powder metallurgy sintering process, separate forging process and subsequent solid solution, aging and other heat treatment processes; the application is suitable for preparing hypereutectic aluminum-silicon alloy (the silicon content is 12-25wt.%); the main reason for the performance improvement of the aluminum-silicon alloy prepared by the application is microstructure strengthening, and no other alloying elements need to be added for reinforcement, so that the alloy has higher high-temperature strength and heat resistance; and the whole preparation process of the application can be carried out in air atmosphere; the application has the advantages of simple process, convenient operation and few steps, and is suitable for large-scale industrial production of aluminum-silicon alloy forgings. The application realizes the synchronous completion of powder metallurgy sintering and forging of aluminum-silicon alloy under pressure through a simple technique, and obtains aluminum-silicon alloy forged piece products with fine microstructure and high mechanical properties.

[0080] The preparation method provided by the application can realize rapid sintering and forging deformation under pressure simultaneously, and the high mechanical properties of the forged piece can be realized without separate powder metallurgy sintering process, separate forging process and subsequent solid solution, aging and other heat treatment processes; the application is suitable for preparing hypereutectic aluminum-silicon alloy (the silicon content is 12-25wt.%); the main reason for the performance improvement of the aluminum-silicon alloy prepared by the application is microstructure strengthening, and no other alloying elements need to be added for reinforcement, so that the alloy has higher high-temperature strength and heat resistance; and the whole preparation process of the application can be carried out in air atmosphere; the application has the advantages of simple process, convenient operation and few steps, and is suitable for large-scale industrial production of aluminum-silicon alloy forgings. The application realizes the synchronous completion of powder metallurgy sintering and forging of aluminum-silicon alloy under pressure through a simple technique, and obtains aluminum-silicon alloy forged piece products with fine microstructure and high mechanical properties.

[0081] While the application has been described and illustrated with reference to specific embodiments thereof, those skilled in the art will appreciate that various adaptations, changes, modifications, substitutions, developments, improvements, and permutations can be made in the specific embodiments described without departing from the true spirit and scope of the application as defined by the appended claims. All such modifications are intended to be within the scope of the claims. Although methods disclosed herein have been described with reference to particular operations performed in a particular order, it will be understood that these operations can be combined, sub-divided, or re-ordered to form equivalent methods without departing from the teachings of the present application. Accordingly, unless specifically indicated herein, the order and grouping of operations are not a limitation of this application.

Claims

1.A method for preparing a hypereutectic Al-Si alloy forging, comprising: high-energy ball-milling aluminum powder and silicon powder to obtain a mixed powder; the mixed powder comprises: 12-25 wt% silicon; and the balance aluminum; adding a control agent during the high-energy ball-milling process; the amount of the control agent added is 28-48 microliters per gram of the mixed powder; the high-energy ball-milling time is selected from 28-35 hours; isostatic pressing the mixed powder to obtain a preform; preheating the preform and then performing forging sintering to obtain a high-performance Al-Si alloy forging; the forging sintering is performed in a forging die, and the temperature of the forging die during the forging sintering is selected from 320-360℃; the forging sintering process comprises a first pressing stage and a second pressing stage; the first pressing stage speed is selected from 0.5-0.6 mm / s; and the second pressing stage speed is selected from 10-12 mm / s. the control agent is selected from ethanol; the ball-to-powder ratio during the high-energy ball-milling process is selected from (10-12) : 1; the average grain size of the mixed powder is selected from 180-400 nm; the isostatic pressing pressure is selected from 200-300 MPa; the isostatic pressing time is selected from 2-5 minutes; the preheating temperature is selected from 600-640℃; and the preheating time is selected from 2-5 minutes. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ 2. The production method according to claim 1, characterized by, ​ 3. The preparation method according to claim 1, characterized in that, ​ 4. The method of claim 1, wherein, ​ 5. The preparation method according to claim 1, characterized in that, ​ 6. The method of claim 1, wherein, ​ 7. The preparation method according to claim 1, characterized in that, ​ 8. The method of claim 1, wherein, ​

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