A high-toughness aluminum alloy material and a method for manufacturing the same

Abstract

The application discloses a high-toughness aluminum alloy material and relates to the technical field of alloys. When the high-toughness aluminum alloy material is prepared, a toughening phase is obtained by depositing a TiB2-HfC gradient transition layer on the surface of a silicon carbide fiber, then, an AlMgB14-TiO2 nano composite phase is used as a nano phase, finally, the toughening phase, the nano phase and aluminum alloy powder are mixed, and the aluminum alloy is prepared by using an interlaminar laying mode. The high-toughness aluminum alloy material prepared by the application has good mechanical properties.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of alloy, in particular to a high-toughness aluminum alloy material and a preparation method thereof. BACKGROUND

[0002] Aluminum alloy has become an important lightweight material in automobile manufacturing industry due to its small density, good plasticity and good specific strength, and is widely used in manufacturing automobile frame structural parts, suspension systems and the like. However, with the development of society, the requirements of users for the aluminum material of automobile lightweight are also higher and higher, and the aluminum material needs to have certain strength and good plasticity. However, in the actual extrusion process, the aluminum alloy often has low hardness, and the mechanical properties after natural aging or artificial aging cannot meet the standard. When used in load-bearing structure, the strength thereof cannot meet the design requirements of automobile load strength, which may cause structural deformation. The strength performance of the traditional high-toughness aluminum alloy material needs to be improved, which limits its more extensive application. SUMMARY

[0003] The present application aims to provide a high-toughness aluminum alloy material and a preparation method and application thereof, so as to solve the problems in the prior art.

[0004] In order to solve the above technical problems, the present application provides the following technical scheme:

[0005] A preparation method of a high-toughness aluminum alloy material, comprising the following steps:

[0006] (1) Preparation of toughening phase: forming a TiB2-HfC gradient transition layer on the surface of silicon carbide fiber to obtain the toughening phase in three stages;

[0007] (2) Preparation of nano phase: mixing Al powder, Mg powder and B powder and heat treating to obtain AlMgB 14 ceramic powder; mixing AlMgB 14 ceramic powder and TiO2 nanoparticles and ball milling to obtain the nano phase;

[0008] (3) Mixing: uniformly mixing and ball milling the toughening phase, the nano phase and the aluminum alloy powder to obtain a mixed material A; uniformly mixing the nano phase and the aluminum alloy powder to obtain a mixed material B;

[0009] (4) Cold pressing forming: loading the mixed material and the aluminum alloy powder into a mold in a layer-by-layer laying manner, and pressing into a green body;

[0010] (5) Vacuum hot pressing sintering: placing the green body in a high-temperature resistance furnace, heating to 550-575℃, and heat treating at 45MPa for 120-130min to obtain an alloy precursor;

[0011] (6) T6 heat treatment: after solution treatment at 515℃ for 2 hours, water quenching and aging at 190℃ for 8 hours, high toughness aluminum alloy material is obtained.

[0012] As an optimization, the preparation method of the toughening phase in step (1) is as follows: after annealing silicon carbide fibers in an Ar atmosphere at 900°C for 30-40 min, the fibers are placed in a chemical vapor deposition reactor and evacuated to 10°C. -3 Pa, Ar gas is introduced for protection, the temperature is raised to 1000℃, and H2 is introduced for 10 min to reduce the surface of silicon carbide fiber; TiB2-HfC gradient transition layer is formed by chemical deposition on the surface of silicon carbide fiber in three stages.

[0013] First stage of deposition:

[0014] Temperature 1050℃, pressure 1.0 kPa, time 30 min;

[0015] Gas composition: TiCl4, 5% B2H6 / H2 mixture, H2, Ar;

[0016] Second stage of deposition:

[0017] Temperature 1010℃, pressure 1.2 kPa, time 40 min

[0018] The gas composition for the first 20 minutes was: TiCl4, 5% B2H6 / H2 mixture, H2, CH4, HfCl4, and Ar;

[0019] The gas composition for the last 20 minutes was HfCl4, CH4, and H2;

[0020] Third stage of deposition:

[0021] Temperature 1150℃, pressure 1.5 kPa, time 30 min;

[0022] The gas composition at this stage is: HfCl4, CH4, H2, and Ar.

[0023] As an optimization, the preparation method of the nanophase in step (2) is as follows: Al powder, Mg powder and B powder are mixed, heated to 950℃, heat-treated for 1 hour, and then heated to 1200℃ for 4 hours to obtain AlMgB. 14 ceramic powder, AlMgB 14 Ceramic powder, TiO2 nanoparticles, and anhydrous ethanol were added to a planetary ball mill at a ball-to-particle ratio of 10:1. The mixture was ball-milled at 300 rpm for 4 hours and then sintered at 900-1000℃ and 30-40 MPa for 1-2 hours to obtain a nanophase.

[0024] As optimization, the molar ratio of the alloy powder Al powder, Mg powder, B powder in step (2) is 1:1:(14-14.5); the particle size of the TiO2 is 50 nm, and the addition amount is 10%-15% of the total mass of the Al powder, Mg powder, and B powder; the addition amount of the anhydrous ethanol is 0.4-0.5 times the total mass of the ceramic powder and TiO2 nanoparticles. 14 The ceramic powder, TiO2 nanoparticles total mass is 0.4-0.5 times.

[0025] As optimization, the preparation method of the mixed material A in step (3) is: taking by weight percentage, toughening phase 15%-20%, nano phase 10%-12%, aluminum alloy powder 68%-75%; mixing the toughening phase, nano phase, and aluminum alloy powder, adding to the ball mill for ball milling, to obtain the mixed material A.

[0026] As optimization, the preparation method of the mixed material B in step (3) is: taking by weight percentage, nano phase 5%-10%, aluminum alloy powder 90%-95%; mixing the nano phase and aluminum alloy powder, adding to the ball mill for ball milling, to obtain the mixed material B.

[0027] As optimization, the ball milling conditions of the ball mill are: the ball-to-material ratio is (8-10):1, the rotation speed is 150-180 rpm, and the ball milling time is 2-3 h.

[0028] As optimization, the preparation method of the green body in step (4) is: the mixed powder is loaded into the mold by the layer-by-layer laying method, and laid according to the following steps:

[0029] a. Laying a 0.5 mm thick pure aluminum alloy powder layer at the bottom of the mold;

[0030] b. Laying a 0.3 mm thick mixed material A layer (fiber orientation parallel to the X axis);

[0031] c. Laying a 0.1 mm thick mixed material B layer;

[0032] d. Laying a 0.3 mm thick mixed material A layer (fiber orientation parallel to the Y axis);

[0033] e. Laying a 0.1 mm thick mixed material B layer;

[0034] f. Repeating steps b-e until the mold is full;

[0035] g. Laying a 0.5 mm thick aluminum alloy powder layer on the top layer;

[0036] Pressing into a green body under a pressure of 600 MPa for 15-20 min.

[0037] As optimization, the silicon carbide fiber in step (1) is a 15-17 μm fiber.

[0038] The application further provides the high-toughness aluminum alloy material prepared by the method.

[0039] Compared with the prior art, the application has the following beneficial effects:

[0040] The TiB2-HfC gradient transition layer constructed at the fiber interface of the application can eliminate the thermal stress mutation between silicon carbide and metal, form a double chemical anchoring of B-Si / Al-O covalent bond and nano transition phase at the molecular level, and improve the interface bonding strength.

[0041] AlMgB 14 The toughening mechanism of the TiO2 nano composite ceramic phase presents a multi-stage response characteristic: the ball milling process in-situ embeds TiO2 nano islands in the grain boundary, and the TiO2 nano islands form a semi-coherent interface and become an energy trap for dislocation movement. 14 When loaded, the high-hardness AlMgB 14 The skeleton forces the crack to bypass, and the local shear strain field induced by the TiO2 particles activates the aluminum lattice distortion, so that the crack tip continuously consumes kinetic energy.

[0042] The interlaminar placement architecture constructs a three-dimensional toughening skeleton, and the orthogonally arranged silicon carbide fiber layers form a spatial defense network: the crack is first forced to turn and expand along the X-direction fiber, and when it penetrates the mixed B layer, the nano phase triggers micro-plastic deformation to form the first energy consumption barrier; when the crack continues to invade the vertical Y-direction fiber layer, the crack path is again forced to deflect 90°; this periodic orthogonal turning structure makes the crack kinetic energy decay, and the nano phase composite matrix in the mixed B layer plays a key role - it not only buffers the stress interference between adjacent fiber layers, but also delays the interface debonding through nano particle bridging; and the surface pure aluminum layer absorbs residual energy through large-scale plastic deformation in the final fracture stage.

[0043] The synergistic effect of the three forms a full-scale protection system: the gradient layer resolves the interface stress concentration and inhibits crack initiation from the source; the nano phase lays a micro-obstacle network in the matrix to collapse the crack propagation energy; the orthogonal layers convert the straight-line expanding crack into a zigzag energy-consuming path; and the surface pure aluminum layer finally completes the energy dissipation closed loop, so that the material can still maintain structural integrity under extreme working conditions such as ultra-low temperature impact and high-cycle fatigue. DETAILED DESCRIPTION

[0044] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments of the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort belong to the scope of the present application.

[0045] In the following examples and comparative examples, the sccm is a unit of gas flow; 5% in the 5% B2H6 / H2 mixed gas refers to a volume ratio, that is, the mixed gas is composed of 5% B2H6 and 95% H2; the particle size of the TiO2 is 50 nm; the aluminum alloy powder is AA2024 aluminum alloy powder; the particle size of the Al powder is 200 mesh, the particle size of the Mg powder is 300 mesh, and the particle size of the B powder is 500 mesh.

[0046] Example 1

[0047] A high-toughness aluminum alloy material, and a preparation method of the material is as follows:

[0048] (1) Preparation of toughening phase: 15 μm silicon carbide fibers are cleaned by ultrasonic washing with acetone and dried, then annealed at 900°C for 40 min in an Ar atmosphere, and then placed in a chemical vapor deposition reactor, vacuumed to 10 -3 Pa, Ar gas is introduced for protection (200 sccm), the temperature is increased to 1000°C at a rate of 10°C / min, and the surface of the silicon carbide fibers is activated by reducing H2 (200 sccm) for 10 min; a TiB2-HfC gradient transition layer is formed on the surface of the silicon carbide fibers in three stages by chemical deposition;

[0049] First stage deposition:

[0050] Temperature 1050°C, pressure 1.0 kPa, time 30 min

[0051] Gas composition: TiCl4 (20 sccm carried by Ar carrier gas), 5% B2H6 / H2 mixed gas (10 sccm), H2 (300 sccm, reducing agent), Ar (170 sccm, diluent gas)

[0052] Second stage deposition:

[0053] Temperature 1010°C, pressure 1.2 kPa, time 40 min

[0054] Gas composition in the first 20 min: TiCl4 (10 sccm), 5% B2H6 / H2 mixed gas (5 sccm), H2 (300 sccm, reducing agent), CH4 (15 sccm, carbon source), HfCl4 (10 sccm, evaporator temperature 80°C), Ar (170 sccm, diluent gas)

[0055] The gas composition in the last 20 min is HfCl4 (flow rate of 20 seem, evaporator temperature of 80 DEG C), CH4 (30 seem, carbon source), H2 (300 seem, reducing agent);

[0056] The third stage deposition:

[0057] Temperature 1150 DEG C, pressure 1.5 kPa, time 30 min;

[0058] The gas composition in this stage is HfCl4 (15 seem, evaporator temperature of 80 DEG C), CH4 (30 seem, carbon source), H2 (300 seem, reducing agent), Ar (155 seem, dilution gas)

[0059] After the deposition is completed, the TiCl4 and B2H6 / H2 mixed gas is stopped. The reactor temperature is lowered to 200 DEG C at a rate of 5 DEG C / min under the protection of H2 (100 seem) and Ar (200 seem);

[0060] (2) Preparation of nano-phase: Al powder, Mg powder and B powder are weighed according to the molar ratio of 1:1:14, and TiO2 nanoparticles are weighed, and the addition amount is 10% of the total mass of Al powder, Mg powder and B powder;

[0061] The Al powder, Mg powder and B powder are mixed, heated to 950 DEG C at a heating rate of 10 DEG C / min, heat treated for 1 h, and then heated to 1200 DEG C at a heating rate of 5 DEG C / min, heat treated for 4 h to obtain AlMgB14 ceramic powder. The AlMgB 14 The ceramic powder, TiO2 nanoparticles and anhydrous ethanol are placed in a planetary ball mill, the ball-to-material ratio is 10:1, and the uniform mixed powder is obtained by ball milling at 300 rpm for 4 h. After vacuum drying, the nano-phase is obtained by sintering at 1000 DEG C and 40 MPa for 2 h. The addition amount of anhydrous ethanol is 0.4 times the total mass of the ceramic powder and TiO2 nanoparticles; 14 The addition amount of anhydrous ethanol is 0.4 times the total mass of the ceramic powder and TiO2 nanoparticles;

[0062] (3) Mixing: the toughening phase is 15%, the nano-phase is 10%, and the aluminum alloy powder is 75% by weight percentage; the toughening phase, the nano-phase and the aluminum alloy powder are uniformly mixed and added to the ball mill to obtain a mixed material A; the nano-phase is 5% and the aluminum alloy powder is 95% by weight percentage; the nano-phase and the aluminum alloy powder are uniformly mixed and added to the ball mill to obtain a mixed material B; the ball-to-material ratio is 8:1, the rotation speed is 180 rpm, and the ball milling time is 3 h;

[0063] (4) Cold pressing: the mixed powder is loaded into the mold by the interlaminar laying method, and the following steps are laid:

[0064] a. Poured 0.5 mm thick pure aluminum alloy powder layer on the bottom of the mold;

[0065] b. Poured 0.3 mm thick layer of mixture A (fiber orientation parallel to X axis);

[0066] c. Poured 0.1 mm thick layer of mixture B;

[0067] d. Poured 0.3 mm thick layer of mixture A (fiber orientation parallel to Y axis);

[0068] e. Poured 0.1 mm thick layer of mixture B;

[0069] f. Repeated steps b-e until the mold was full;

[0070] g. Poured 0.5 mm thick aluminum alloy powder layer on the top;

[0071] Pressed into a billet under 600 MPa pressure for 20 min.

[0072] (5) Vacuum hot-pressing sintering: placed the billet in a high-temperature resistance furnace, heated to 575°C at a heating rate of 15°C / min, and treated at 45 MPa for 130 min to obtain an alloy precursor;

[0073] (6) T6 heat treatment: solution treated at 515°C for 2 h, water quenched, and aged at 190°C for 8 h to obtain a high-toughness aluminum alloy material.

[0074] Example 2:

[0075] A high-toughness aluminum alloy material, the preparation method of which is as follows:

[0076] (1) Preparation of toughening phase: after 17 μm silicon carbide fibers were cleaned with acetone by ultrasonic and dried, annealed at 900°C for 35 min in an Ar atmosphere, and placed in a chemical vapor deposition reactor, vacuumed to 10 -3 Pa, Ar protective gas (200 sccm) was introduced, heated to 1000°C at a rate of 10°C / min, and H2 (200 sccm) was introduced to reduce the surface of the silicon carbide fibers for 10 min to activate them; a TiB2-HfC gradient transition layer was formed on the surface of the silicon carbide fibers by chemical deposition in three stages;

[0077] First stage deposition:

[0078] Temperature 1050°C, pressure 1.0 kPa, time 30 min;

[0079] Gas composition: TiCl4 (20 sccm carried by Ar), 5% B2H6 / H2 mixture (10 sccm), H2 (300 sccm, reducing agent), Ar (170 sccm, dilution gas);

[0080] Second stage deposition:

[0081] Temperature 1010℃, pressure 1.2 kPa, time 40 min

[0082] Gas composition for the first 20 min: TiCl4 (10 sccm), 5% B2H6 / H2 mixture (5 sccm), H2 (300 sccm, reducing agent), CH4 (15 sccm, carbon source), HfCl4 (10 sccm, evaporator temperature 80℃), Ar (170 sccm, dilution gas);

[0083] Gas composition for the last 20 min: HfCl4 (flow rate 20 sccm, evaporator temperature 80℃), CH4 (30 sccm, carbon source), H2 (300 sccm, reducing agent);

[0084] Third stage deposition:

[0085] Temperature 1150℃, pressure 1.5 kPa, time 30 min;

[0086] Gas composition for this stage: HfCl4 (15 sccm, evaporator temperature 80℃), CH4 (gas flow rate 30 sccm, carbon source), H2 (300 sccm, reducing agent), Ar (155 sccm, dilution gas)

[0087] After deposition, stop feeding TiCl4 and B2H6 / H2 mixture, under the protection of H2 (100 sccm) and Ar (200 sccm), reduce the reactor temperature to 200℃ at a rate of 5℃ / min;

[0088] (2) Preparation of nanophase: Al powder, Mg powder and B powder are weighed according to the molar ratio of 1:1:14.3, and TiO2 nanoparticles are weighed, the particle size of TiO2 is 50 nm, and the addition amount is 12% of the total mass of Al powder, Mg powder and B powder;

[0089] Mix Al powder, Mg powder and B powder, heat to 950℃ at a rate of 10℃ / min, heat treat for 1h, heat to 1200℃ at a rate of 5℃ / min, heat treat for 4h to obtain AlMgB14 ceramic powder, and then heat treat the AlMgB 14Ceramic powder, TiO2 nanoparticles, anhydrous ethanol were placed in a planetary ball mill, the ball-to-powder ratio was 10:1, and the uniform mixed powder was obtained by ball milling at 300 rpm for 4 h. After vacuum drying, the nanophase was obtained by sintering at 950℃ under 35 MPa for 1.5 h. The addition amount of anhydrous ethanol was 0.45 times the total mass of ceramic powder and TiO2 nanoparticles. 14 Ceramic powder, TiO2 nanoparticles, anhydrous ethanol were placed in a planetary ball mill, the ball-to-powder ratio was 10:1, and the uniform mixed powder was obtained by ball milling at 300 rpm for 4 h. After vacuum drying, the nanophase was obtained by sintering at 950℃ under 35 MPa for 1.5 h. The addition amount of anhydrous ethanol was 0.45 times the total mass of ceramic powder and TiO2 nanoparticles.

[0090] (3) Mixing: according to the weight percentage, 17% of toughening phase, 11% of nanophase, and 72% of aluminum alloy powder were weighed and mixed uniformly, and then added to the ball mill to obtain mixed material A; according to the weight percentage, 7% of nanophase and 93% of aluminum alloy powder were weighed and mixed uniformly, and then added to the ball mill to obtain mixed material B; the ball-to-powder ratio was 9:1, the rotation speed was 170 rpm, and the ball milling time was 2.5 h;

[0091] (4) Cold pressing forming: the mixed powder was loaded into the mold by using the layer-by-layer laying method, and the following steps were followed:

[0092] a. A 0.5 mm thick pure aluminum alloy powder layer was laid on the bottom of the mold;

[0093] b. A 0.3 mm thick mixed material A layer (fiber orientation parallel to X axis) was laid;

[0094] c. A 0.1 mm thick mixed material B layer was laid;

[0095] d. A 0.3 mm thick mixed material A layer (fiber orientation parallel to Y axis) was laid;

[0096] e. A 0.1 mm thick mixed material B layer was laid;

[0097] f. Steps b-e were repeated until the mold was full;

[0098] g. A 0.5 mm thick aluminum alloy powder layer was laid on the top;

[0099] The green body was pressed under a pressure of 600 MPa for 17 min;

[0100] (5) Vacuum hot pressing sintering: the green body was placed in a high-temperature resistance furnace, heated to 560℃ at a heating rate of 15℃ / min, and treated at 45 MPa for 125 min to obtain an alloy precursor;

[0101] (6) T6 heat treatment: after solution treatment at 515℃ for 2 h and water quenching, high-toughness aluminum alloy material was obtained by aging at 190℃ for 8 h.

[0102] Example 3:

[0103] A high-toughness aluminum alloy material, the preparation method of which is as follows:

[0104] (1) Preparation of toughening phase: 18 μm silicon carbide fibers were cleaned by ultrasonic in acetone and dried, then annealed at 900 ℃ for 30 min in Ar atmosphere, and placed in a chemical vapor deposition reactor, vacuumed to 10 -3 Pa, Ar protection gas (200 sccm) was introduced, and the temperature was raised to 1000 ℃ at a rate of 10 ℃ / min, and the surface of the silicon carbide fibers was activated by reduction with H2 (200 sccm) for 10 min; a TiB2-HfC gradient transition layer was formed on the surface of the silicon carbide fibers by chemical deposition in three stages;

[0105] First stage deposition:

[0106] Temperature 1050 ℃, pressure 1.0 kPa, time 30 min;

[0107] Gas composition: TiCl4 (20 sccm carried by Ar carrier gas), 5% B2H6 / H2 mixed gas (10 sccm), H2 (300 sccm, reducing agent), Ar (170 sccm, diluent gas);

[0108] Second stage deposition:

[0109] Temperature 1010 ℃, pressure 1.2 kPa, time 40 min

[0110] Gas composition in the first 20 min: TiCl4 (10 sccm), 5% B2H6 / H2 mixed gas (5 sccm), H2 (300 sccm, reducing agent), CH4 (15 sccm, carbon source), HfCl4 (10 sccm, evaporator temperature 80 ℃), Ar (170 sccm, diluent gas);

[0111] Gas composition in the last 20 min: HfCl4 (flow rate 20 sccm, evaporator temperature 80 ℃), CH4 (30 sccm, carbon source), H2 (300 sccm, reducing agent);

[0112] Third stage deposition:

[0113] Temperature 1150 ℃, pressure 1.5 kPa, time 30 min;

[0114] Gas composition in this stage: HfCl4 (15 sccm, evaporator temperature 80 ℃), CH4 (gas flow rate 30 sccm, carbon source), H2 (300 sccm, reducing agent), Ar (155 sccm, diluent gas)

[0115] After the deposition is completed, stop the TiCl4 and B2H6 / H2 mixed gas, and lower the reactor temperature to 200℃ at a rate of 5℃ / min under the protection of H2 (100 sccm) and Ar (200 sccm);

[0116] (2) Preparation of the nano-phase: Al powder, Mg powder, and B powder are weighed according to a molar ratio of 1:1:14.5, and TiO2 nanoparticles are weighed, the particle size of TiO2 is 50 nm, and the addition amount is 15% of the total mass of the Al powder, Mg powder, and B powder;

[0117] The Al powder, Mg powder, and B powder are mixed, heated to 950℃ at a heating rate of 10℃ / min, heat treated for 1h, and then heated to 1200℃ at a heating rate of 5℃ / min for heat treatment for 4h to obtain AlMgB14 ceramic powder. The AlMgB 14 The ceramic powder, TiO2 nanoparticles, and anhydrous ethanol are placed in a planetary ball mill, the ball-to-material ratio is 10:1, and the uniform mixed powder is obtained by ball milling at 300 rpm for 4h. After vacuum drying, the nano-phase is obtained by sintering at 900℃ and 30 MPa for 1h. The addition amount of anhydrous ethanol is 0.5 times the total mass of the ceramic powder and TiO2 nanoparticles; 14 The addition amount of anhydrous ethanol is 0.5 times the total mass of the ceramic powder and TiO2 nanoparticles;

[0118] (3) Mixing: the toughening phase is 20%, the nano-phase is 12%, and the aluminum alloy powder is 68% according to the weight percentage; the toughening phase, the nano-phase, and the AA2024 aluminum alloy powder are uniformly mixed and added to the ball mill to obtain a mixed material A; the nano-phase is 10%, and the aluminum alloy powder is 90% according to the weight percentage; the nano-phase and the aluminum alloy powder are uniformly mixed and added to the ball mill to obtain a mixed material B; the ball-to-material ratio is 10:1, the rotation speed is 150 rpm, and the ball milling time is 2h;

[0119] (4) Cold pressing forming: the mixed powder is loaded into the mold by the interlaminar laying method, and the following steps are laid:

[0120] a. A 0.5 mm thick pure aluminum alloy powder layer is laid on the bottom of the mold;

[0121] b. A 0.3 mm thick mixed material A layer (fiber orientation parallel to the X axis) is laid;

[0122] c. A 0.1 mm thick mixed material B layer is laid;

[0123] d. A 0.3 mm thick mixed material A layer (fiber orientation parallel to the Y axis) is laid;

[0124] e. A 0.1 mm thick mixed material B layer is laid;

[0125] f. Steps b-e are repeated until the mold is full;

[0126] g. Top layer of 0.5 mm thick aluminum alloy powder layer;

[0127] Compacting into a blank under 600 MPa pressure for 15 min;

[0128] (5) Vacuum hot-pressing sintering: placing the blank in a high-temperature resistance furnace, heating to 550℃ at a heating rate of 15℃ / min, and treating at 45 MPa for 120 min to obtain an alloy precursor;

[0129] (6) T6 heat treatment: solid solution at 515℃ for 2 h, water quenching, and aging at 190℃ for 8 h to obtain a high-toughness aluminum alloy material.

[0130] Comparative Example 1:

[0131] The preparation method of the high-toughness aluminum alloy material of Comparative Example 1 differs from that of Example 2 in that the silicon carbide fibers are not modified; specifically, step (1) is not included; step (3) is modified as follows: weighing by percentage by weight, 17% silicon carbide fibers, 11% nano-phase, and 70% aluminum alloy powder; mixing the silicon carbide fibers, nano-phase, and aluminum alloy powder, and adding them to a ball mill to obtain a mixture A; weighing by percentage by weight, 7% nano-phase and 93% aluminum alloy powder; mixing the nano-phase and aluminum alloy powder, and adding them to a ball mill to obtain a mixture B; the ball-to-material ratio is 9:1, the rotation speed is 170 rpm, and the ball milling time is 2.5 h.

[0132] Comparative Example 2:

[0133] The preparation method of the high-toughness aluminum alloy material of Comparative Example 2 differs from that of Example 2 in that it does not include a nano-phase; specifically, step (2) is not included, and step (3) is modified as follows: mixing: weighing by percentage by weight, 17% toughening phase and 93% aluminum alloy powder; mixing the toughening phase and aluminum alloy powder, and adding them to a ball mill to obtain a mixture A; weighing by percentage by weight, 100% aluminum alloy powder, and adding it to a ball mill to obtain a mixture B; the ball-to-material ratio is 9:1, the rotation speed is 170 rpm, and the ball milling time is 2.5 h.

[0134] Comparative Example 3:

[0135] The preparation method of the high-toughness aluminum alloy material of Comparative Example 3 differs from that of Example 2 in that the layer-by-layer deposition method is different; specifically, step (4) is modified as follows: cold pressing: the mixed powder is loaded into a mold using a layer-by-layer deposition method, and is deposited according to the following steps:

[0136] a. Bottom layer of 0.5 mm thick pure aluminum alloy powder layer;

[0137] b. Layer of 0.3 mm thick mixture A;

[0138] c. Lay a 0.1 mm thick layer of mixture B;

[0139] d. Lay a 0.3 mm thick layer of mixture A;

[0140] e. Lay a 0.1 mm thick layer of mixture B;

[0141] f. Repeat steps b-e until the mold is full;

[0142] g. Top layer of 0.5 mm thick aluminum alloy powder layer;

[0143] Pressing into a blank under a pressure of 600 MPa for 17 min.

[0144] Test Example:

[0145] Mechanical property test method: tensile strength and elongation are used to evaluate the mechanical properties of the prepared high-toughness aluminum alloy material, and the specific test method is as follows: mechanical property test is carried out according to GB / T 228.1-2021, the length of the sample is 140 mm, the width is 18 mm, the gauge length is 50 mm, the thickness is 3 mm, the tensile speed is 3 mm / min, and the tensile strength, yield strength and elongation are tested, 5 samples are tested in each group to take the average value and record. The results are shown in Table 1:

[0146]

[0147] From the comparison of the experimental data of examples 1-3 and comparative examples 1-2 in table 1, it can be found that the high-toughness aluminum alloy material prepared by the present application has good tensile strength and elongation.

[0148] The mechanical properties of examples 1-3 are better than those of the comparative examples, which shows that the high-toughness aluminum alloy material prepared by the present application has good tensile strength and elongation. 14 The toughening mechanism of the TiO2 nano-composite ceramic phase presents a multi-level response characteristic: the ball milling process in-situ embeds TiO2 nano-islands in the grain boundaries, forming a semi-coherent interface and becoming an energy trap for dislocation movement; under load, the high-hardness AlMgB 14 The high-hardness AlMgB 14 The skeleton forces the crack to bypass, while the local shear strain field induced by the TiO2 particles activates the aluminum lattice distortion, making the crack tip continuously consume kinetic energy.

[0149] The interlaminar placement architecture builds a three-dimensional toughening framework, and the orthogonally arranged silicon carbide fiber layers form a spatial defense network: the crack is first forced to turn and expand along the X-direction fiber, and when it penetrates the B layer, the nano-phase triggers micro-plastic deformation to form the first energy dissipation barrier; when the crack continues to invade the vertical Y-direction fiber layer, the crack path is again forced to deflect 90°; this periodic orthogonal turning structure makes the crack kinetic energy decay, and the nano-phase composite matrix in the B layer plays a key role: it not only buffers the stress interference between adjacent fiber layers, but also delays the interface debonding through nano-particle bridging; and the surface pure aluminum layer then accommodates residual energy through large-scale plastic deformation in the final fracture stage.

[0150] The synergistic effect of the three forms a full-scale protection system: the gradient layer resolves the interface stress concentration, inhibiting crack initiation from the source; the nano-phase sets up a micro-obstacle network in the matrix, breaking down the crack propagation kinetic energy; the orthogonal placement turns the linearly expanding crack into a zigzag energy-consuming path; and the surface pure aluminum layer finally completes the energy dissipation closed loop, enabling the material to maintain structural integrity under extreme working conditions such as ultra-low temperature impact and high-cycle fatigue.

[0151] It is apparent for those skilled in the art that the present application is not limited to the details of the foregoing exemplary embodiments, and can be implemented in other concrete forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be considered in all respects as illustrative and not restrictive, and the scope of the present application is defined by the appended claims rather than the above description, and it is intended to embrace all changes falling within the meaning and scope of the equivalent elements of the claims. Any mark in the claims should not be considered as limiting the involved claims.

Claims

1. A method for preparing a high-toughness aluminum alloy material, comprising the following steps: (1) Preparation of toughening phase: forming a TiB2-HfC gradient transition layer on the surface of silicon carbide fibers to obtain a toughening phase in three stages; (2) Preparation of nanophase: Al powder, Mg powder, B powder are mixed and heat treated to obtain AlMgB 14 ceramic powder; AlMgB 14 ceramic powder, TiO2 nanoparticles are mixed and ball milled to obtain nanophase; (3) Mixing: uniformly mixing the toughening phase, nano-phase and aluminum alloy powder to obtain a mixture A; uniformly mixing the nano-phase and aluminum alloy powder to obtain a mixture B; (4) Cold pressing: filling the mixture and aluminum alloy powder into a mold by using the layer-by-layer laying method to press a blank; The preparation method of the blank is as follows: filling the mixed powder into a mold by using the layer-by-layer laying method, and laying according to the following steps: a. Laying a 0.5 mm thick pure aluminum alloy powder layer on the bottom of the mold; b. Laying a 0.3 mm thick mixture A layer, with the fiber orientation parallel to the X axis; c. Laying a 0.1 mm thick mixture B layer; d. Laying a 0.3 mm thick mixture A layer, with the fiber orientation parallel to the Y axis; e. Laying a 0.1 mm thick mixture B layer; f. Repeating steps b-e until the mold is full; g. Laying a 0.5 mm thick aluminum alloy powder layer on the top layer; Pressing the blank under a pressure of 600 MPa for 15-20 min; (5) Vacuum hot pressing and sintering: placing the blank in a high-temperature resistance furnace, heating to 550-575℃, and treating under a pressure of 45 MPa for 120-130 min to obtain an alloy precursor; (6) T6 heat treatment: water quenching after solid solution at 515℃ for 2 h, and aging at 190℃ for 8 h to obtain a high-toughness aluminum alloy material.

2. The method of making a high toughness aluminum alloy material of claim 1, wherein, The preparation method of the toughening phase in step (1) is as follows: after the silicon carbide fiber is annealed at 900 DEG C for 30-40 min in Ar atmosphere, it is placed in a chemical vapor deposition reactor, vacuumed to 10 -3 Pa, Ar gas is introduced for protection, and the temperature is raised to 1000 DEG C, H2 is introduced for 10 min to reduce the surface of the silicon carbide fiber; the TiB2-HfC gradient transition layer is formed on the surface of the silicon carbide fiber in three stages by chemical deposition; First stage deposition: Temperature 1050℃, pressure 1.0 kPa, time 30 min; Gas Composition: TiCl4, 5% B2H6 / H2 mixed gas, H2 gas, Ar gas; Second stage deposition: Temperature 1010℃, pressure 1.2 kPa, time 40 min Gas composition in the first 20 min: TiCl4, 5% B2H6 / H2 mixed gas, H2, CH4, HfCl4, Ar; Gas composition in the last 20 min: HfCl4, CH4, H2; Third stage deposition: Temperature 1150℃, pressure 1.5 kPa, time 30 min; Gas composition in this stage: HfCl4, CH4, H2, Ar.

3. The method of making a high toughness aluminum alloy material of claim 1, wherein, The preparation method of the nanophase in step (2) is: mixing Al powder, Mg powder and B powder, heating to 950°C, heat treating for 1 h, heating to 1200°C, heat treating for 4 h to obtain AlMgB 14 ceramic powder, TiO2nanoparticles, anhydrous ethanol are added into a planetary ball mill, the ball-to-material ratio is 10:1, ball milling is performed at 300 rpm for 4 h, sintering is performed at 900-1000°C and 30-40 MPa for 1-2 h to obtain the nanophase. 14 ceramic powder, TiO2nanoparticles, anhydrous ethanol are added into a planetary ball mill, the ball-to-material ratio is 10:1, ball milling is performed at 300 rpm for 4 h, sintering is performed at 900-1000°C and 30-40 MPa for 1-2 h to obtain the nanophase.

4. The method of making a high toughness aluminum alloy material of claim 3, wherein, The molar ratio of the alloy powder Al powder, Mg powder, B powder in step (2) is 1:1:(14-14.5); the TiO2 addition amount is 10%-15% of the total mass of Al powder, Mg powder, B powder; the addition amount of anhydrous ethanol is 0.4-0.5 times of the total mass of AlMgB 14 The total mass of ceramic powder, TiO2 nanoparticles is 0.4-0.5 times.

5. The method of making a high toughness aluminum alloy material of claim 1, wherein, The preparation method of the mixture A in step (3) is as follows: weighing the toughening phase 15%-20%, the nano-phase 10%-12% and the aluminum alloy powder 68%-75% by weight percentage; uniformly mixing the toughening phase, the nano-phase and the aluminum alloy powder, and adding them into a ball mill for ball milling to obtain the mixture A.

6. The method of making a high toughness aluminum alloy material of claim 1, wherein, The preparation method of the mixture B in step (3) is as follows: weighing the nano-phase 5%-10% and the aluminum alloy powder 90%-95% by weight percentage; uniformly mixing the nano-phase and the aluminum alloy powder, and adding them into a ball mill for ball milling to obtain the mixture B.

7. The method of making a high toughness aluminum alloy material of either of claims 5 or 6, wherein, The ball milling conditions of the ball mill are as follows: ball-to-material ratio (8-10):1, rotation speed 150-180 rpm, and ball milling time 2-3 h.

8. The method of producing a high toughness aluminum alloy material according to claim 1, characterized by, The silicon carbide fibers in step (1) are 15-18 μm fibers.

9. A high-toughness aluminum alloy material prepared by the method according to claim 1.

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