Rare earth-containing high-strength high-toughness 6063 aluminum alloy material and preparation method thereof

Abstract

The invention discloses a rare earth element-containing high-strength and high-toughness 6063 aluminum alloy material and a preparation method thereof, and relates to the technical field of preparation and processing of nonferrous metal materials, and the aluminum alloy material comprises the following components in percentage by weight: 0.2-0.6% of silicon, 0.45-0.9% of magnesium, less than 0.35% of iron, and less than 0.1% of other impurity elements (Cu, Ti, Zr, Cr and the like). The content of rare earth is 0.1%-0.2%, and the balance is Al. Alloy raw materials are prepared according to the component requirements of the 6063 aluminum alloy; melting an aluminum ingot; adding magnesium, silicon and other elements, and fully stirring the melt to obtain a 6063 aluminum alloy melt; the aluminum alloy melt is purified; adding rare earth into the alloy melt, fully stirring and preserving heat; cooling and solidifying the alloy melt through a crystallizer to obtain an aluminum alloy cast ingot; the aluminum alloy cast ingot is subjected to homogenization treatment; carrying out solid solution and quenching treatment on the homogenized aluminum alloy; and the quenched alloy is subjected to aging treatment. The 6063 aluminum alloy material prepared by the preparation method disclosed by the invention has relatively high strength and elongation.

Description

Technical Field

[0001] The present invention relates to a rare earth-containing high-strength and high-toughness 6063 aluminum alloy material and a preparation method thereof, belonging to the technical field of preparation and processing of non-ferrous metal materials. Background Art

[0002] As an important lightweight industrial aluminum profile material, high-strength and high-toughness aluminum alloys are increasingly widely used in industries such as automobiles, aerospace, rail transit, and high-end equipment.

[0003] As an important lightweight industrial aluminum profile material, high-strength and high-toughness aluminum alloys are increasingly widely used in industries such as automobiles, aerospace, rail transit, and high-end equipment. The 6-series aluminum alloy is the most important wrought alloy in wrought aluminum alloys and belongs to the Al-Mg-Si system. Now, a high-strength and high-toughness 6063 aluminum alloy material and a preparation method thereof are provided, which can meet its application in fields such as automobiles, aerospace, rail transit, and high-end equipment.

[0004] Based on this, now a rare earth-containing high-strength and high-toughness 6063 aluminum alloy material and a preparation method thereof are provided, which can solve the problems of insufficient strength and toughness of existing 6063 aluminum alloys. Summary of the Invention

[0005] The purpose of the present invention is to provide a rare earth-containing high-strength and high-toughness 6063 aluminum alloy material and a preparation method thereof to meet the needs of the national economy and national defense for high-strength and high-toughness 6063 aluminum alloy materials. This alloy has excellent mechanical properties such as high strength and high toughness compared with the existing 6063 aluminum alloy.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] A rare earth-containing high-strength and high-toughness 6063 aluminum alloy material, by weight percentage, the aluminum alloy material includes the following components: 0.2 - 0.6% of silicon, 0.45 - 0.9% of magnesium, iron less than 0.35%, and the remaining impurity elements (such as Cu, Ti, Zr, Cr, etc.) are all less than 0.1%. The rare earth content is 0.1% - 0.2%, and the balance is Al.

[0008] The preparation method of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material includes the following steps:

[0009] Step 1: Prepare alloy raw materials according to the composition requirements of 6063 aluminum alloy, put pure aluminum into a melting furnace to melt, and adjust the melt temperature to 730°C - 760°C;

[0010] Step 2: Add magnesium and silicon elements to the melt in Step 1 in the form of pure magnesium or Al-Mg master alloy, and pure silicon or Al-Si master alloy, stir the alloy melt to obtain 6063 aluminum alloy melt, and add purification materials to the 6063 aluminum alloy melt for purification treatment;

[0011] Step 3: Adjust the temperature of the 6063 aluminum alloy melt to 680°C - 710°C, add rare earth (Ce, Pr, Gd) elements or Al-(Ce, Pr, Gd) master alloy to the 6063 aluminum alloy melt, stir and keep the temperature of the 6063 aluminum alloy melt to ensure the uniformity of its components, and cool and solidify the 6063 aluminum alloy melt through a mold to obtain an aluminum alloy ingot;

[0012] Step 4: Homogenize the 6063 aluminum alloy ingot, heat it to 555°C - 565°C, keep it warm for 6 - 10 hours, cool it to room temperature by air cooling after taking it out of the furnace and then by water cooling;

[0013] Step 5: Solution treat the 6063 aluminum alloy ingot, heat, keep it warm and then quench it to room temperature by water cooling. After quenching, heat and keep the temperature of the 6063 aluminum alloy ingot and then carry out aging treatment, and cool it to room temperature with the furnace.

[0014] Based on the above technical solutions, the present invention also provides the following alternative technical solutions:

[0015] In an alternative solution: Before adding the rare earth (Ce, Pr, Gd) elements to the aluminum alloy melt, the hydrogen content in the aluminum alloy melt is below 0.15 ml / 100gAl.

[0016] In an alternative solution: Add rare earth (Ce, Sr, Sc) elements to the aluminum alloy melt in the form of high-purity rare earth (Ce, Pr, Gd) or Al-(Ce, Pr, Gd) master alloy.

[0017] In an alternative solution: The purification material consists of a refining agent and high-purity nitrogen.

[0018] In an alternative solution: This material has high strength and good elongation, its tensile strength ≥ 350 MPa, and elongation ≥ 8%.

[0019] In an alternative solution: When the 6063 aluminum alloy profile is solution treated, the heating temperature is 530°C - 550°C, and the quenching and heat preservation duration of the 6063 aluminum alloy profile is 3 - 5 hours.

[0020] In an alternative solution: When the 6063 aluminum alloy profile is aged, the heating temperature is 180°C - 200°C, and the aging treatment heat preservation duration of the 6063 aluminum alloy profile is 8 - 12 hours.

[0021] The advantages of the present invention compared with the prior art are as follows:

[0022] In the 6063 aluminum alloy of the present invention, by adding rare earths (Ce, Pr, Gd), after the addition of rare earths (Ce, Pr, Gd), the size of the iron-rich precipitation phase in the alloy can be significantly reduced, thereby improving the elongation of the alloy; after the addition of rare earths (Ce, Pr, Gd), the nucleation rate of α-Al can be increased, thus playing a role in refining the grains; after the addition of rare earths (Ce, Pr, Gd), the number density of the (Mg, Si) precipitation phase in the alloy can be greatly increased and its size can be reduced, thereby improving the strength and toughness of the alloy; the 6063 aluminum alloy material prepared by the present invention has excellent mechanical properties, with high strength and good elongation, its tensile strength ≥ 350 MPa, elongation ≥ 8%, and this high-strength and high-toughness aluminum alloy material has great application prospects in the fields of aerospace and transportation. Specific embodiments

[0023] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0024] In the embodiments of the present invention, a rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is composed of the following elements by weight percentage: 0.2 - 0.6% of silicon, 0.45 - 0.9% of magnesium, iron less than 0.35%, and the remaining impurity elements (such as Cu, Ti, Zr, Cr, etc.) are all less than 0.1%. The rare earth content is 0.1% - 0.2%, and the balance is Al.

[0025] The preparation method of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is as follows: Prepare alloy raw materials according to the composition requirements of 6063 aluminum alloy; Put pure aluminum into a melting furnace to melt, and adjust the melt temperature to 740°C - 760°C; Add elements such as magnesium and silicon to the melt in the form of pure magnesium or Al-Mg master alloy, and pure silicon or Al-Si master alloy, and stir the alloy melt to obtain 6063 aluminum alloy melt; Pass a refining agent (such as a mixture of calcium sulfate, sodium chloride, magnesium fluoride and graphite, etc.) and high-purity nitrogen (volume purity 99.999%) into the melt for purification treatment; Adjust the alloy melt temperature to 690°C - 710°C, and add (Ce, Pr, Gd) elements to the melt in the form of high-purity rare earth (Ce, Pr, Gd) (purity ≥ 99.5wt%) or Al-(Ce, Pr, Gd) master alloy, and stir and keep the alloy melt warm to ensure the uniformity of its components; Cool and solidify the alloy melt through a crystallizer to obtain an aluminum alloy ingot; Homogenize the aluminum alloy ingot, heat it to 555°C - 565°C, keep it warm for 6 - 10 hours, and cool it to room temperature by air cooling and then water mist cooling after taking it out of the furnace; Solution treat the aluminum alloy ingot, heat it to 530°C - 550°C, keep it warm for 3 - 5 hours and then perform water quenching to room temperature; Heat the quenched alloy to 180°C - 200°C and keep it warm for 8 - 12 hours for aging treatment, and cool it to room temperature with the furnace.

[0026] Example 1

[0027] In this example, by weight percentage, the formula ratio of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is as follows: magnesium 0.6%, silicon 0.6%, rare earth (Ce, Pr, Gd) 0.12%, and the balance is Al. 0.2% silicon, 0.9% magnesium, 0.32% iron, and the remaining impurity elements (such as Cu, Ti, Zr, Cr, etc.) 0.08%. The rare earth content is 0.12%, and the balance is Al.

[0028] In this example, the preparation method of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is as follows:

[0029] Step 1: Prepare alloy raw materials according to the above composition requirements;

[0030] Step 2: Put pure aluminum into a melting furnace to melt, and adjust the melt temperature to 730°C;

[0031] Step 3: Add elements such as magnesium and silicon to the melt in the form of Al-Mg master alloy and Al-Si master alloy, and stir the alloy melt to obtain 6063 aluminum alloy melt;

[0032] Step 4: Pass a refining agent and high-purity nitrogen into the melt for purification treatment;

[0033] Step 5: Adjust the temperature of the alloy melt to 680 °C, add (Ce, Pr, Gd) elements to the melt in the form of high-purity rare earths (Ce, Pr, Gd) or Al-(Ce, Pr, Gd) master alloys, and stir and keep the alloy melt warm to ensure the uniformity of its components;

[0034] Step 6: Cool and solidify the alloy melt through a crystallizer to obtain an aluminum alloy ingot;

[0035] Step 7: Homogenize the alloy ingot, heat it to 555 °C, keep it warm for 6 hours, air-cool it after taking it out of the furnace, and then water-cool it to room temperature;

[0036] Step 8: Solution-treat the alloy ingot, heat it to 530 °C, keep it warm for 3 hours, and then water-quench it to room temperature;

[0037] Step 9: Heat the quenched alloy to 180 °C, keep it warm for 8 hours for aging treatment, and cool it to room temperature with the furnace;

[0038] During the aluminum alloy melting process, control the hydrogen content in the aluminum alloy melt. Before adding rare earth metals to the aluminum alloy melt, the hydrogen content in the aluminum alloy melt is 0.15 ml / 100 g Al.

[0039] In this embodiment, the tensile strength of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is 358 MPa, and the elongation is 8.7%.

[0040] Example 2

[0041] In this embodiment, by weight percentage, 0.6% silicon, 0.45% magnesium, 0.30% iron, and the remaining impurity elements (Cu, Ti, Zr, Cr, etc.) 0.09%. The rare earth content is 0.2%, and the balance is Al.

[0042] In this embodiment, the preparation method of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is as follows:

[0043] Step 1: Prepare alloy raw materials according to the above composition requirements;

[0044] Step 2: Put pure aluminum into a melting furnace to melt it, and adjust the melt temperature to 760 °C;

[0045] Step 3: Add elements such as magnesium and silicon to the melt in the form of Al-Mg master alloy and Al-Si master alloy, and stir the alloy melt to obtain 6063 aluminum alloy melt;

[0046] Step 4: Pass a refining agent and high-purity nitrogen into the melt for purification treatment;

[0047] Step 5: Adjust the temperature of the alloy melt to 710 °C, add (Ce, Pr, Gd) elements into the melt in the form of high-purity rare earth (Ce, Pr, Gd) or Al-(Ce, Pr, Gd) master alloy, and stir and keep the alloy melt warm to ensure the uniformity of its components;

[0048] Step 6: Cool and solidify the alloy melt through a crystallizer to obtain an aluminum alloy ingot;

[0049] Step 7: Homogenize the alloy ingot, heat it to 560 °C, keep it warm for 10 hours, and then cool it to room temperature by air cooling after taking it out of the furnace and then water cooling;

[0050] Step 8: Solution-treat the alloy ingot, heat it to 540 °C, keep it warm for 4 hours, and then water quench it to room temperature;

[0051] Step 9: Solutionize the quenched alloy, heat it to 190 °C, keep it warm for 12 hours for aging treatment, and then cool it to room temperature with the furnace;

[0052] During the aluminum alloy melting process, control the hydrogen content in the aluminum alloy melt. Before adding rare earth metals into the aluminum alloy melt, the hydrogen content in the aluminum alloy melt is 0.15 ml / 100 g Al.

[0053] In this embodiment, the tensile strength of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is 365 MPa, and the elongation is 9.1%.

[0054] Example 3

[0055] In this embodiment, by weight percentage, the formula ratio of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is as follows: 0.4% silicon, 0.7% magnesium, 0.34% iron, and the remaining impurity elements (Cu, Ti, Zr, Cr, etc.) 0.07%. The rare earth content is 0.15%, and the balance is Al.

[0056] In this embodiment, the preparation method of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is as follows:

[0057] Step 1: Prepare alloy raw materials according to the above composition requirements;

[0058] Step 2: Put pure aluminum into a melting furnace to melt it, and adjust the temperature of the melt to 730 °C;

[0059] Step 3: Add elements such as magnesium and silicon into the melt in the form of Al-Mg master alloy and Al-Si master alloy, and stir the alloy melt to obtain a 6063 aluminum alloy melt;

[0060] Step 4: Pass a refining agent and high-purity nitrogen into the melt for purification treatment;

[0061] Step 5: Adjust the temperature of the alloy melt to 710 °C, add (Ce, Pr, Gd) elements to the melt in the form of high-purity rare earths (Ce, Pr, Gd) or Al(Ce, Pr, Gd) master alloys, and stir and hold the alloy melt to ensure the uniformity of its components;

[0062] Step 6: Cool and solidify the alloy melt through a crystallizer to obtain an aluminum alloy ingot;

[0063] Step 7: Homogenize the alloy ingot, heat it to 565 °C, hold it for 8 hours, and cool it to room temperature by air cooling after taking it out of the furnace and then water cooling;

[0064] Step 8: Solution treat the alloy ingot, heat it to 550 °C, hold it for 5 hours, and then water quench it to room temperature;

[0065] Step 9: Solutionize the quenched alloy, heat it to 200 °C, hold it for 10 hours for aging treatment, and cool it to room temperature with the furnace;

[0066] During the melting process of the aluminum alloy, control the hydrogen content in the aluminum alloy melt. Before adding rare earth metals to the aluminum alloy melt, the hydrogen content in the aluminum alloy melt is 0.15 ml / 100 g Al.

[0067] In this embodiment, the tensile strength of the high-strength 6063 aluminum alloy material is 350 MPa, and the elongation is 8%.

[0068] Comparative Example

[0069] In this embodiment, by weight percentage, the formula ratio of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is as follows: 0.4% silicon, 0.7% magnesium, 0.34% iron, the remaining impurity elements (Cu, Ti, Zr, Cr, etc.) 0.07%, and the balance is Al.

[0070] In this embodiment, the preparation method of the rare earth-containing high-strength and high-toughness 6063 aluminum alloy material is as follows:

[0071] Step 1: Prepare alloy raw materials according to the above composition requirements;

[0072] Step 2: Put pure aluminum into a melting furnace to melt it, and adjust the melt temperature to 730 °C;

[0073] Step 3: Add elements such as magnesium and silicon to the melt in the form of Al-Mg master alloy and Al-Si master alloy, and stir the alloy melt to obtain a 6063 aluminum alloy melt;

[0074] Step 4: Pass a refining agent and high-purity nitrogen into the melt for purification treatment;

[0075] Step 5: Cool and solidify the alloy melt through a crystallizer to obtain an aluminum alloy ingot;

[0076] Step 7: Homogenize the alloy ingot by heating it to 565°C, holding for 8 hours, cooling it in air after taking it out of the furnace, and then water-cooling it to room temperature.

[0077] Step 8: Solution-treat the alloy ingot by heating it to 550°C, holding for 5 hours, and then water-quenching it to room temperature.

[0078] Step 9: Age the quenched alloy by heating it to 200°C, holding for 10 hours for aging treatment, and then cooling it to room temperature in the furnace.

[0079] During the melting process of the aluminum alloy, control the hydrogen content in the aluminum alloy melt. Before adding the rare earth metal to the aluminum alloy melt, the hydrogen content in the aluminum alloy melt is 0.15 ml / 100 g Al.

[0080] In this embodiment, the tensile strength of the high-strength 6063 aluminum alloy material is 329 MPa, and the elongation is 7.2%.

[0081] Rare earths (Ce, Pr, Gd) are added to the 6063 aluminum alloy of the present invention, and the alloy properties can be improved in the following aspects: 1. After adding rare earths (Ce, Pr, Gd), the size of the iron-rich precipitation phase in the alloy can be significantly reduced, thereby improving the elongation of the alloy; 2. After adding rare earths (Ce, Pr, Gd), the nucleation rate of α-Al can be increased, thereby playing a role in refining the grains; 3. After adding rare earths (Ce, Pr, Gd), the number density of the (Mg, Si) precipitation phase in the alloy can be greatly increased and its size can be reduced, thereby improving the strength of the alloy.

[0082] The above is only the specific embodiment of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed in the present application, and all should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A rare earth-containing high-strength and high-toughness 6063 aluminum alloy material, characterized in that, By weight percentage, 0.2 - 0.6% of silicon, 0.45 - 0.9% of magnesium, iron less than 0.35%, and the remaining impurity elements (such as Cu, Ti, Zr, Cr, etc.) are all less than 0.1%. The rare earth content is 0.1% - 0.2%, and the balance is Al.

2. A preparation method of the high-strength and high-toughness 6063 aluminum alloy material according to claim 1, characterized in that, It includes the following steps: Step 1: Prepare alloy raw materials according to the composition requirements of 6063 aluminum alloy. Put pure aluminum into a melting furnace to melt, and adjust the melt temperature to 730°C - 760°C; Step 2: Add magnesium and silicon elements to the melt in Step 1 in the form of pure magnesium or Al-Mg master alloy, pure silicon or Al-Si master alloy, and stir the alloy melt to obtain 6063 aluminum alloy melt, and add a purification material to the 6063 aluminum alloy melt for purification treatment; Step 3: Adjust the temperature of the 6063 aluminum alloy melt to 680°C - 710°C, add rare earth elements of (Ce, Pr, Gd) or Al-(Ce, Pr, Gd) master alloy to the 6063 aluminum alloy melt, and stir and keep warm the 6063 aluminum alloy melt to ensure its components are uniform, and make the 6063 aluminum alloy melt achieve cooling and solidification through a mold to obtain an aluminum alloy ingot; Step 4: Perform homogenization treatment on the 6063 aluminum alloy ingot, heat it to 555°C - 565°C, keep warm for 6 - 10 hours, and cool it to room temperature by air cooling after taking it out of the furnace and then water cooling; Step 5: Subject the homogenized 6063 aluminum alloy to solution treatment, keep warm and then water quench it to room temperature. Heat and keep warm the quenched 6063 aluminum alloy profile and then perform aging treatment, and cool it to room temperature with the furnace.

3. The preparation method of a rare earth-containing high-strength and high-toughness 6063 aluminum alloy material according to claim 2, characterized in that, Before adding the rare earth elements of (Ce, Pr, Gd) or Al-(Ce, Pr, Gd) master alloy to the aluminum alloy melt, the hydrogen content in the aluminum alloy melt is below 0.15 ml / 100gAl.

4. The preparation method of a rare earth-containing high-strength and high-toughness 6063 aluminum alloy material according to claim 2, characterized in that, Add rare earth elements of (Ce, Pr, Gd) to the aluminum alloy melt in the form of high-purity rare earth (Ce, Pr, Gd) or Al-(Ce, Pr, Gd) master alloy.

5. The preparation method of a rare earth-containing high-strength and high-toughness 6063 aluminum alloy material according to claim 2, wherein, The purification material consists of a refining agent and high-purity nitrogen.

6. The preparation method of a rare-earth-containing high-strength and high-toughness 6063 aluminum alloy material according to claim 2, characterized in that, When the 6063 aluminum alloy profile is solution-treated, the heating temperature is 530°C - 550°C, and the quenching holding time of the 6063 aluminum alloy is 3 - 5 hours.

7. The preparation method of a rare earth-containing high-strength and high-toughness 6063 aluminum alloy material according to claim 2, wherein, When the 6063 aluminum alloy profile is aged, the heating temperature is 180°C - 200°C, and the aging holding time of the 6063 aluminum alloy profile is 8 - 12 hours.