High-strength aluminum material and process for producing the same

Abstract

The application discloses high-strength aluminum material, comprising the following components in percentage by mass: Ce 0.7-1.1%, La 0.8-1.2%, Cu 0.2-0.25%, Mg 0.018-0.036%, Ag 0.012-0.018%, Si 0.12-0.16%, Cr 0.08-0.12%, Ti 0.05-0.08%, Zr 0.02-0.06%, Sc 0.002-0.004%, and the balance of Al and inevitable impurities. The application discloses high-strength aluminum material and a manufacturing method thereof, and the obtained aluminum alloy has high strength and good fracture toughness.

Description

Technical Field

[0001] The present invention relates to the technical field of aluminum alloys, and in particular to a high-strength aluminum material and a preparation process thereof. Background Art

[0002] Aluminum alloys, while boasting excellent properties such as high strength, high elastic modulus, high toughness, high hardenability, and excellent corrosion resistance, have found widespread application in the automotive, shipbuilding, and aerospace industries. However, with the continuous advancement of technology, the performance of traditional metal alloys alone is no longer sufficient to meet the demands of today's high-tech products. Microalloying can imbue alloy systems with new potential and fundamentally eliminate certain performance deficiencies. The addition of small or even trace amounts of certain elements to aluminum alloys can significantly affect their microstructure and properties. Summary of the Invention

[0003] In view of this, an object of the present invention is to provide a high-strength aluminum material and a method for manufacturing the same, wherein the obtained aluminum alloy has high strength and good fracture toughness.

[0004] In order to achieve the above object, the present invention provides the following technical solutions:

[0005] A high-strength aluminum material comprises the following components in percentage by mass: Ce 0.7-1.1%, La 0.8-1.2%, Cu 0.2-0.25%, Mg 0.018-0.036%, Ag 0.012-0.018%, Si 0.12-0.16%, Cr 0.08-0.12%, Ti 0.05-0.08%, Zr 0.02-0.06%, Sc 0.002-0.004%, and the balance being Al and unavoidable impurities.

[0006] Preferably, the steel comprises the following components in percentage by mass: Ce 1.1%, La 1.2%, Cu 0.25%, Mg 0.036%, Ag 0.018%, Si 0.16%, Cr 0.12%, Ti 0.08%, Zr 0.06%, Sc 0.004%, and the balance is Al and unavoidable impurities.

[0007] A process for preparing a high-strength aluminum material comprises the following steps:

[0008] The high-strength aluminum material is obtained by sequentially subjecting raw materials composed of pure aluminum and aluminum master alloy with corresponding mass percentages to smelting and casting, homogenization treatment, solid solution treatment and aging treatment.

[0009] Preferably, the specific method of smelting and casting is: first add pure aluminum and Al-TiC, Al-Sc-Zr master alloys into a preheated crucible, heat to 800-850°C for smelting, and after completely melting into molten metal, add Al-Si, Al-Ce, Al-La, Al-Cu, Al-Mg, Al-Ag, Al-Cr master alloys, stir, and after all melted, let it stand and keep warm for 20-30 minutes, remove the slag and cast to obtain an aluminum alloy billet.

[0010] Preferably, the homogenization treatment is a heating-cooling homogenization treatment process.

[0011] Preferably, the heating-cooling homogenization process is specifically as follows:

[0012] The temperature of the heating homogenization treatment is raised to 470-500°C and the holding time is 12h;

[0013] The temperature for cooling and homogenizing treatment is 450-460°C, and the holding time is 12h.

[0014] Preferably, the solution treatment process is specifically as follows: heating the ionic molten salt to 460-480° C. and keeping the temperature for 1 hour.

[0015] Preferably, the ionic molten salt includes silver nitrate, copper nitrate, magnesium nitrate, magnesium pyrophosphate and silicic acid.

[0016] Preferably, the weight ratio of the silver nitrate, copper nitrate, magnesium nitrate, magnesium pyrophosphate and silicic acid is 5:5:5:2:1.

[0017] Preferably, the aging treatment is a three-stage aging treatment: 120°C / 6h+140°C / 6h+120°C / 3h, that is, the temperature of the first-stage aging treatment is 120°C, and the holding time is 6h; the temperature of the second-stage aging treatment is 140°C, and the holding time is 6h; the temperature of the third-stage aging treatment is 120°C, and the holding time is 3h.

[0018] The nanoparticles of the present invention are uniformly dispersed in the matrix alloy. When the composite material is deformed, the nanoparticles can effectively hinder the movement of dislocations in the matrix, the size of α-Al dendrites is significantly refined, and the morphology is continuously transformed into equiaxed crystals. The nano-TiC particles play the role of a heterogeneous core in the matrix alloy and play a role in grain refinement during the solidification of the composite material, so that the grains present an equiaxed crystal shape. The increase in angular grain boundaries is accompanied by an increase in recrystallized grains, thereby improving the mechanical properties of the composite material. The heating-cooling homogenization treatment and the aging treatment enable the Sc and Zr atoms in the alloy to be fully precipitated, and the formed precipitated phase is coherent with the matrix alloy, thereby significantly improving the hardness of the alloy.

[0019] In addition, with the addition of the Al-TiC and Al-Sc-Zr master alloys of the present invention, TiC can pin subgrains during the aging treatment process, while Sc and Zr can further prevent static recrystallization of the alloy, hindering dynamic recovery while stabilizing the substructure, reducing the fraction of high-angle grain boundaries in the composite material, forming dislocation walls, and thereby improving the tensile strength and elongation of the composite material. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work are within the scope of protection of the present invention. In addition, it is specifically stated that the raw materials and equipment of the present invention can be obtained from commercial sources and are not listed one by one.

[0021] Example 1

[0022] A high-strength aluminum material comprises the following components by mass percentage: Ce 1.1%, La 1.2%, Cu 0.25%, Mg 0.036%, Ag 0.018%, Si 0.16%, Cr 0.12%, Ti 0.08%, Zr 0.06%, Sc 0.004%, with the balance being Al and unavoidable impurities.

[0023] A process for preparing a high-strength aluminum material comprises the following steps:

[0024] The raw materials composed of pure aluminum and aluminum master alloy with corresponding mass percentage are sequentially subjected to melting and casting, heating-cooling homogenization treatment, solid solution treatment and three-stage aging treatment to obtain high-strength aluminum materials.

[0025] Among them, the specific method of melting and casting is: first add pure aluminum and Al-TiC, Al-Sc-Zr master alloys into a preheated crucible, heat to 800-850℃ for melting, and after completely melting into molten metal, add Al-Si, Al-Ce, Al-La, Al-Cu, Al-Mg, Al-Ag, Al-Cr master alloys, stir, and after all melted, let it stand and keep warm for 30 minutes, remove the slag and cast to obtain aluminum alloy billets.

[0026] The specific heating-cooling homogenization process is as follows:

[0027] The temperature of the heating homogenization treatment is raised to 500°C and the holding time is 12 hours; the temperature of the cooling homogenization treatment is 460°C and the holding time is 12 hours.

[0028] The specific solution treatment process is as follows: heating the ionic molten salt to 480°C and keeping the temperature for 1 hour.

[0029] The ionic molten salt includes silver nitrate, copper nitrate, magnesium nitrate, magnesium pyrophosphate and silicic acid, and the weight ratio of silver nitrate, copper nitrate, magnesium nitrate, magnesium pyrophosphate and silicic acid is 5:5:5:2:1.

[0030] Among them, the three-level aging treatment is: 120℃ / 6h+140℃ / 6h+120℃ / 3h, that is, the temperature of the first-level aging treatment is 120℃, and the holding time is 6h; the temperature of the second-level aging treatment is 140℃, and the holding time is 6h; the temperature of the third-level aging treatment is 120℃, and the holding time is 3h.

[0031] Example 2

[0032] A high-strength aluminum material comprises the following components in percentage by mass: 0.7% Ce, 0.8% La, 0.2% Cu, 0.018% Mg, 0.012% Ag, 0.12% Si, 0.08% Cr, 0.05% Ti, 0.02% Zr, 0.002% Sc, and the balance being Al and unavoidable impurities.

[0033] A process for preparing a high-strength aluminum material comprises the following steps:

[0034] The raw materials composed of pure aluminum and aluminum master alloy with corresponding mass percentage are sequentially subjected to melting and casting, heating-cooling homogenization treatment, solid solution treatment and three-stage aging treatment to obtain high-strength aluminum materials.

[0035] Among them, the specific method of melting and casting is: first add pure aluminum and Al-TiC, Al-Sc-Zr master alloys into a preheated crucible, heat to 800-850℃ for melting, and after completely melting into molten metal, add Al-Si, Al-Ce, Al-La, Al-Cu, Al-Mg, Al-Ag, Al-Cr master alloys, stir, and after all melted, let it stand and keep warm for 20-30 minutes, remove the slag and cast to obtain aluminum alloy billets.

[0036] The specific heating-cooling homogenization process is as follows:

[0037] The temperature of the heating homogenization treatment is raised to 470°C and the holding time is 12 hours; the temperature of the cooling homogenization treatment is 450°C and the holding time is 12 hours.

[0038] The specific solution treatment process is as follows: heating the ionic molten salt to 460°C and keeping the temperature for 1 hour.

[0039] The ionic molten salt includes silver nitrate, copper nitrate, magnesium nitrate, magnesium pyrophosphate and silicic acid, and the weight ratio of silver nitrate, copper nitrate, magnesium nitrate, magnesium pyrophosphate and silicic acid is 5:5:5:2:1.

[0040] Among them, the three-level aging treatment is: 120℃ / 6h+140℃ / 6h+120℃ / 3h, that is, the temperature of the first-level aging treatment is 120℃, and the holding time is 6h; the temperature of the second-level aging treatment is 140℃, and the holding time is 6h; the temperature of the third-level aging treatment is 120℃, and the holding time is 3h.

[0041] Example 3

[0042] A high-strength aluminum material comprises the following components in percentage by mass: Ce 0.8%, La 1.0%, Cu 0.22%, Mg 0.028%, Ag 0.016%, Si 0.15%, Cr 0.1%, Ti 0.06%, Zr 0.04%, Sc 0.003%, and the balance being Al and unavoidable impurities.

[0043] A process for preparing a high-strength aluminum material comprises the following steps:

[0044] The raw materials composed of pure aluminum and aluminum master alloy with corresponding mass percentage are sequentially subjected to melting and casting, heating-cooling homogenization treatment, solid solution treatment and three-stage aging treatment to obtain high-strength aluminum materials.

[0045] Among them, the specific method of melting and casting is: first add pure aluminum and Al-TiC, Al-Sc-Zr master alloys into a preheated crucible, heat to 820℃ for melting, and after completely melting into molten metal, add Al-Si, Al-Ce, Al-La, Al-Cu, Al-Mg, Al-Ag, Al-Cr master alloys, stir, and after all melted, let it stand and keep warm for 25 minutes, remove the slag and cast to obtain aluminum alloy billets.

[0046] The specific heating-cooling homogenization process is as follows:

[0047] The temperature of the heating homogenization treatment is raised to 480°C and the holding time is 12 hours; the temperature of the cooling homogenization treatment is 455°C and the holding time is 12 hours.

[0048] The specific solution treatment process is as follows: heating the ionic molten salt to 470°C and keeping the temperature for 1 hour.

[0049] The ionic molten salt includes silver nitrate, copper nitrate, magnesium nitrate, magnesium pyrophosphate and silicic acid, and the weight ratio of silver nitrate, copper nitrate, magnesium nitrate, magnesium pyrophosphate and silicic acid is 5:5:5:2:1.

[0050] Among them, the three-level aging treatment is: 120℃ / 6h+140℃ / 6h+120℃ / 3h, that is, the temperature of the first-level aging treatment is 120℃, and the holding time is 6h; the temperature of the second-level aging treatment is 140℃, and the holding time is 6h; the temperature of the third-level aging treatment is 120℃, and the holding time is 3h.

[0051] Comparative Example 1

[0052] The component quality and preparation process of Comparative Example 1 are basically the same as those of Example 1, except that Al-TiC and Al-Sc-Zr master alloys are not used. Specifically:

[0053] A high-strength aluminum material comprises the following components by mass percentage: Ce 1.1%, La 1.2%, Cu 0.25%, Mg 0.036%, Ag 0.018%, Si 0.16%, Cr 0.12%, and the balance being Al and unavoidable impurities.

[0054] A process for preparing a high-strength aluminum material comprises the following steps:

[0055] The raw materials composed of pure aluminum and aluminum master alloy with corresponding mass percentage are sequentially subjected to melting and casting, heating-cooling homogenization treatment, solid solution treatment and three-stage aging treatment to obtain high-strength aluminum materials.

[0056] Among them, the specific method of melting and casting is: first add pure aluminum, Al-Si, Al-Ce, Al-La, Al-Cu, Al-Mg, Al-Ag, and Al-Cr intermediate alloys, stir, and after all are melted, let it stand and keep warm for 30 minutes, remove the slag and cast to obtain aluminum alloy billets.

[0057] The specific heating-cooling homogenization process is as follows:

[0058] The temperature of the heating homogenization treatment is raised to 500°C and the holding time is 12 hours; the temperature of the cooling homogenization treatment is 460°C and the holding time is 12 hours.

[0059] The specific solution treatment process is as follows: heating the ionic molten salt to 480°C and keeping the temperature for 1 hour.

[0060] The ionic molten salt includes silver nitrate, copper nitrate, magnesium nitrate, magnesium pyrophosphate and silicic acid, and the weight ratio of silver nitrate, copper nitrate, magnesium nitrate, magnesium pyrophosphate and silicic acid is 5:5:5:2:1.

[0061] Among them, the three-level aging treatment is: 120℃ / 6h+140℃ / 6h+120℃ / 3h, that is, the temperature of the first-level aging treatment is 120℃, and the holding time is 6h; the temperature of the second-level aging treatment is 140℃, and the holding time is 6h; the temperature of the third-level aging treatment is 120℃, and the holding time is 3h.

[0062] The hardness, yield strength, tensile strength and elongation of the aluminum alloy samples obtained in Examples 1-3 and Comparative Example 1 were tested.

[0063] Hardness Test: Aluminum alloy samples obtained in Examples 1-3 and Comparative Example 1 were cut into 10 mm × 10 mm × 5 mm squares. These were then smoothed using coarse and then fine sandpaper until they reached the grit of 1500# metallographic sandpaper. The samples were then polished with diamond polishing compound, rinsed, and air-dried for later use. Hardness testing was performed using an HV-1000 microhardness tester.

[0064] Yield strength, tensile strength and elongation tests:

[0065] The dimensions of the room-temperature tensile specimens were designed in accordance with the national standard GB / T228.1-2010. The tensile performance tests were conducted on an INSPEK-Table100 electronic universal tensile testing machine. The actual dimensions of each specimen were precisely determined before the tensile test. The aluminum alloy tensile rate was 3 mm / min, and the tensile test data was automatically collected to determine the alloy's yield strength, tensile strength, and elongation.

[0066] The results are shown in Table 1.

[0067] Table 1

[0068] Test items Example 1 Example 2 Example 3 Comparative Example 1 Hardness (HV) 187.4 185.2 190.1 124.3 Yield strength (MPa) 365.2 321.7 352.6 223.8 Tensile strength (MPa) 369.3 358.4 356.8 204.5 Elongation (%) 5.8 5.8 5.1 4.2

[0069] As can be seen from the above table, the hardness, yield strength, tensile strength and elongation of Examples 1-3 are all improved compared with Comparative Example 1.

[0070] The above description of the disclosed embodiments is intended to enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A process for preparing high-strength aluminum material, characterized in that: The method comprises the following steps: sequentially subjecting raw materials composed of pure aluminum and aluminum master alloy with corresponding mass percentages to smelting and casting, homogenization treatment, solution treatment and aging treatment to obtain the high-strength aluminum material; The specific method of the smelting and casting is as follows: first, pure aluminum and Al-TiC and Al-Sc-Zr master alloys are added to a preheated crucible, heated to 800-850° C. for smelting, and after completely melting into molten metal, Al-Si, Al-Ce, Al-La, Al-Cu, Al-Mg, Al-Ag, and Al-Cr master alloys are added and stirred. After all are melted, the master alloys are allowed to stand and heat for 20-30 minutes, slag is removed, and casting is performed to obtain an aluminum alloy billet; The homogenization treatment is a heating-cooling homogenization treatment process; The high-strength aluminum material includes the following components in percentage by mass: Ce 0.7-1.1%, La 0.8-1.2%, Cu 0.2-0.25%, Mg 0.018-0.036%, Ag 0.012-0.018%, Si 0.12-0.16%, Cr 0.08-0.12%, Ti 0.05-0.08%, Zr 0.02-0.06%, Sc 0.002-0.004%, and the balance is Al and unavoidable impurities.

2. The process for preparing a high-strength aluminum material according to claim 1, wherein: The high-strength aluminum material includes the following components in percentage by mass: Ce 1.1%, La 1.2%, Cu 0.25%, Mg 0.036%, Ag 0.018%, Si 0.16%, Cr 0.12%, Ti 0.08%, Zr 0.06%, Sc 0.004%, and the balance is Al and unavoidable impurities.

3. The process for preparing the high-strength aluminum material according to claim 1, wherein: The heating-cooling homogenization process is specifically as follows: The temperature of the heating homogenization treatment is raised to 470-500℃ and the holding time is 12h; The temperature for the cooling and homogenization treatment is 450-460°C, and the holding time is 12 hours.