Preparation method of high-strength aluminum alloy material for cross coupling of refrigeration equipment

Abstract

The invention discloses a preparation method of a high-strength aluminum alloy material for a cross coupling of refrigeration equipment. The method comprises the following steps that (1) a B390 aluminum ingot is put into a smelting furnace and heated to 580-600 DEG C, a low-temperature slag remover is added, and impurities on the upper layer are removed; (2) continuing to heat until the temperature of the molten aluminum is 750-780 DEG C, adding a high-temperature deslagging agent, and removing upper-layer impurities; (3) refining, degassing and controlling the hydrogen content after high-temperature treatment; and 4) adding an aluminum-strontium alterant accounting for 0.1-0.15% of the weight of the formed new ingot, refining primary silicon from a block shape to fine particles, and enabling the internal structure of the product to be more compact, thereby achieving the effect of improving the performance. By controlling the chemical components and the internal grain structure, the mechanical property of the B390 material is improved, and the wear resistance and fatigue resistance of the product are greatly improved, so that the service life of the whole refrigeration equipment is prolonged.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy materials, and more specifically to a method for preparing high-strength aluminum alloy materials for cross couplings in refrigeration equipment. Background Technology

[0002] As a key connecting component in the transmission system of refrigeration equipment, the cross coupling is subjected to alternating loads and high-frequency micro-amplitude movements over a long period of time. Its performance directly affects the overall operating efficiency and service life of the machine. Currently, the industry generally uses aluminum alloy materials to manufacture cross couplings. Although this has the advantage of lightweighting, it faces the following prominent problems in actual working conditions: 1. Insufficient wear resistance: When refrigeration equipment is running, the coupling works continuously under limited lubrication conditions. Traditional aluminum alloy materials have low surface hardness, making them prone to abrasive and adhesive wear, leading to increased clearance, decreased transmission accuracy, and consequently, vibration and noise. 2. Inadequate fatigue resistance: Under long-term cyclic stress, fatigue cracks are prone to develop in the stress concentration areas of the coupling. Existing aluminum alloy materials have limited fatigue strength, making it difficult to meet the long service life requirements of high-reliability refrigeration equipment. Summary of the Invention

[0003] To extend the service life of refrigeration equipment and improve the wear resistance and fatigue resistance of its cross coupling components, this invention provides a method for preparing high-strength aluminum alloy material for cross couplings in refrigeration equipment.

[0004] The technical solution adopted in this invention is as follows:

[0005] A method for preparing high-strength aluminum alloy material for cross couplings in refrigeration equipment includes the following steps:

[0006] 1) Put B390 aluminum ingots into a melting furnace, heat to 580-600℃, add low-temperature slag remover, stir thoroughly for 3-5 minutes, let stand for 10-15 minutes after stirring, and then remove the impurities on the upper layer.

[0007] 2) Continue heating until the aluminum liquid temperature reaches 750-780℃, add high-temperature slag remover, stir thoroughly for 3-5 minutes, let stand for 10-15 minutes after stirring, and then remove the upper layer of impurities;

[0008] 3) After the aluminum liquid completes the slag removal operation, it is refined and degassed while controlling the hydrogen content;

[0009] 4) After degassing, let stand for 8-10 minutes, add 0.1-0.15% of the weight of the new ingot as an aluminum-strontium alloy modifier, and stir slowly and evenly for 5-8 minutes. After stirring, let stand for 15-20 minutes to refine the primary silicon from blocky to fine particles, making the internal structure of the product denser and thus improving its performance.

[0010] Furthermore, the low-temperature slag remover mentioned in step 1) is an L-type low-temperature slag remover.

[0011] Further, the amount of the low-temperature slag remover mentioned in step 1) is 0.2-0.5% of the weight of B390 aluminum ingot.

[0012] Furthermore, the high-temperature slag remover mentioned in step 2) is an H-type high-temperature slag remover.

[0013] Further, the amount of the high-temperature slag remover mentioned in step 2) is 0.3-0.5% of the weight of B390 aluminum ingot.

[0014] Furthermore, the degassing time in step 3) is 20-25 minutes.

[0015] Furthermore, the hydrogen content in step 3) is controlled to be ≤0.8%.

[0016] Further, the aluminum-strontium alloy modifier mentioned in step 4) is Al-10Sr.

[0017] The aluminum melt obtained by the method of this invention is produced by high-pressure casting and spot cooling with a mold. The resulting cross-shaped product undergoes T5 heat treatment, which forms fine reinforcing phases inside the product, significantly improving the material's strength, hardness, and wear resistance. The mechanical properties of the product meet the following requirements: 1) Tensile strength: ≥330MPa; 2) Yield strength: ≥260MPa; 3) Hardness: ≥80HRB.

[0018] This invention improves the mechanical properties of B390 material by controlling its chemical composition and internal grain structure, significantly enhancing the wear resistance and fatigue resistance of the product, thereby extending the service life of the entire refrigeration equipment. This has earned high recognition and approval from overseas customers. This invention fundamentally solves the industry pain point of insufficient wear resistance and fatigue resistance in traditional aluminum alloy couplings, providing material assurance for the long-life design of highly reliable refrigeration equipment, and possesses significant technical and economic value. Detailed Implementation

[0019] In the following examples, the low-temperature slag remover is an L-type low-temperature slag remover (a commercially available product purchased from Zhangjiagang Solvent Factory No. 2, brand name L-type slag remover).

[0020] The high-temperature slag remover is a type H high-temperature slag remover (commercially available product, purchased from Zhangjiagang Solvent Factory No. 2, brand name: type H slag remover).

[0021] The modifier for aluminum-strontium alloys is Al-10Sr.

[0022] Example 1

[0023] A method for preparing high-strength aluminum alloy material for cross couplings in refrigeration equipment includes the following steps:

[0024] 1) Put B390 aluminum ingots into a smelting furnace, heat to 590℃, add 0.22% of the weight of B390 aluminum ingots of low-temperature slag remover, stir thoroughly for 3.5 minutes, let stand for 10 minutes, and then remove the impurities on the upper layer.

[0025] 2) Continue heating until the aluminum liquid temperature reaches 765℃, add 0.3% of the weight of B390 aluminum ingot with high-temperature slag remover, stir thoroughly for 3 minutes, let stand for 10 minutes, and then remove the upper layer of impurities.

[0026] 3) After the aluminum liquid completes the slag removal operation, it is refined and degassed (degassed for 20 minutes) and the hydrogen content is controlled.

[0027] 4) Add 0.125% of the weight of the newly formed ingot with aluminum-strontium alloy modifier, stir slowly and evenly for 5 minutes, and let stand for 15 minutes after stirring to refine the primary silicon from block to fine particles, making the internal structure of the product more compact, thereby improving its performance.

[0028] 5) The composition and hydrogen content of the molten aluminum after the above steps were tested, as shown in Table 1:

[0029] Table 1 Results of aluminum liquid composition determination

[0030]

[0031] Note: By controlling the Si and Mg content in the treated aluminum liquid to a slightly lower level and the Mn content to below 0.4%, the goal of improving strength, increasing toughness, and reducing brittleness can be achieved.

[0032] 6) The molten aluminum obtained in step 4) is produced by high-pressure casting and spot cooling with a mold. The resulting cross-shaped product undergoes T5 heat treatment, which forms fine reinforcing phases inside the product, significantly improving the material's strength, hardness, and wear resistance. The measured product performance is as follows:

[0033] (1) Tensile strength: 345.53 MPa;

[0034] (2) Yield strength: 296.34 MPa;

[0035] (3) Hardness: 90.7HRB.

[0036] Example 2

[0037] A method for preparing high-strength aluminum alloy material for cross couplings in refrigeration equipment includes the following steps:

[0038] 1) Put B390 aluminum ingots into a melting furnace, heat to 580℃, add 0.38% of the weight of B390 aluminum ingots of low-temperature slag remover, stir thoroughly for 4 minutes, let stand for 12 minutes, and then remove the impurities on the upper layer.

[0039] 2) Continue heating until the aluminum liquid temperature reaches 750℃, add 0.4% of the weight of B390 aluminum ingot with high-temperature slag remover, stir thoroughly for 4 minutes, let stand for 10 minutes, and then remove the upper layer of impurities.

[0040] 3) After the aluminum liquid completes the slag removal operation, it is refined and degassed (degassed for 21 minutes) and the hydrogen content is controlled to be 0.45%;

[0041] 4) Add 0.10% of the weight of the newly formed ingot with aluminum strontium modifier, stir slowly and evenly for 6 minutes, and let stand for 17 minutes after stirring to refine the primary silicon from block to fine particles, making the internal structure of the product more compact and thus improving its performance.

[0042] The molten aluminum obtained in step 4) is produced by high-pressure casting and spot cooling with a mold. The resulting cross-shaped product undergoes T5 heat treatment, which forms fine reinforcing phases within the product, significantly improving its strength, hardness, and wear resistance. The measured product performance is as follows:

[0043] (1) Tensile strength: 338.21 MPa;

[0044] (2) Yield strength: 285.37 MPa;

[0045] (3) Hardness: 89.3 HRB.

[0046] Example 3

[0047] A method for preparing high-strength aluminum alloy material for cross couplings in refrigeration equipment includes the following steps:

[0048] 1) Put B390 aluminum ingots into a melting furnace, heat to 600℃, add 0.5% of the weight of B390 aluminum ingots of low-temperature slag remover, stir thoroughly for 4 minutes, let stand for 12 minutes, and then remove the impurities on the upper layer.

[0049] 2) Continue heating until the aluminum liquid temperature reaches 780℃, add 0.5% of the weight of B390 aluminum ingot with high-temperature slag remover, stir thoroughly for 4 minutes, let stand for 10 minutes, and then remove the upper layer of impurities.

[0050] 3) After the aluminum liquid completes the slag removal operation, it is refined and degassed (degassed for 23 minutes) and the hydrogen content is controlled to be 0.66%;

[0051] 4) Add 0.15% of the weight of the newly formed ingot as an aluminum-strontium modifier, stir slowly and evenly for 8 minutes, and let stand for 20 minutes after stirring to refine the primary silicon from block to fine particles, making the internal structure of the product more compact and thus improving its performance.

[0052] The molten aluminum obtained in step 4) is produced by high-pressure casting and spot cooling with a mold. The resulting cross-shaped product undergoes T5 heat treatment, which forms fine reinforcing phases within the product, significantly improving its strength, hardness, and wear resistance. The measured product performance is as follows:

[0053] (1) Tensile strength: 346.86 MPa;

[0054] (2) Yield strength: 298.29 MPa;

[0055] (3) Hardness: 91.0 HRB.

Claims

1. A method for preparing high-strength aluminum alloy material for cross-type couplings in refrigeration equipment, characterized in that, Includes the following steps: 1) Put B390 aluminum ingots into a melting furnace, heat to 580-600℃, add low-temperature slag remover, stir thoroughly for 3-5 minutes, let stand for 10-15 minutes after stirring, and then remove the impurities on the upper layer. 2) Continue heating until the aluminum liquid temperature reaches 750-780℃, add high-temperature slag remover, stir thoroughly for 3-5 minutes, let stand for 10-15 minutes after stirring, and then remove the upper layer of impurities; 3) After the aluminum liquid completes the slag removal operation, it is refined and degassed while controlling the hydrogen content; 4) After degassing, let stand for 8-10 minutes, add 0.1-0.15% of the weight of the new ingot as aluminum-strontium alloy modifier, stir slowly and evenly for 5-8 minutes, and let stand for 15-20 minutes after stirring.

2. The method for preparing a high-strength aluminum alloy material for a cross-shaped coupling in refrigeration equipment according to claim 1, characterized in that, Step 1) The low-temperature slag remover mentioned is an L-type low-temperature slag remover.

3. The method for preparing a high-strength aluminum alloy material for a cross-shaped coupling in refrigeration equipment according to claim 1, characterized in that, The amount of the low-temperature slag remover mentioned in step 1) is 0.2-0.5% of the weight of B390 aluminum ingot.

4. The method for preparing a high-strength aluminum alloy material for a cross-shaped coupling in refrigeration equipment according to claim 1, characterized in that, The high-temperature slag remover mentioned in step 2) is an H-type high-temperature slag remover.

5. The method for preparing a high-strength aluminum alloy material for a cross-shaped coupling in refrigeration equipment according to claim 1, characterized in that, The amount of high-temperature slag remover used in step 2) is 0.3-0.5% of the weight of B390 aluminum ingot.

6. The method for preparing a high-strength aluminum alloy material for a cross-shaped coupling in refrigeration equipment according to claim 1, characterized in that, The degassing time in step 3) is 20-25 minutes.

7. The method for preparing a high-strength aluminum alloy material for a cross-shaped coupling in refrigeration equipment according to claim 1, characterized in that, The hydrogen content mentioned in step 3) is controlled to be ≤0.8%.

8. The method for preparing a high-strength aluminum alloy material for a cross-shaped coupling in refrigeration equipment according to claim 1, characterized in that, The aluminum-strontium alloy modifier mentioned in step 4) is Al-10Sr.

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