A homogenization heat treatment method for ultra-large 2219 aluminum alloy round ingots

Abstract

This invention provides a homogenization heat treatment method for 2219 aluminum alloy round ingots, comprising the following steps. This invention utilizes a slow heating method at the melting temperature of the low-melting-point eutectic phase to fully leverage the effect of temperature on the dissolution of the eutectic phase. This ensures that the aluminum alloy ingot does not overheat, resulting in more complete dissolution of the low-melting-point eutectic phase, reducing casting internal stress, lowering the risk of cracking in large-sized ingots due to uneven internal and external heating, and eliminating the formation of coarse θ(Al₂Cu) and T(CuMn₂Al) particles during non-equilibrium solidification in semi-continuous casting. 12 This provides high-quality raw materials for subsequent forging, rolling, and other processing methods. Furthermore, the process is simple and clear, highly controllable, and easily executable on-site, making it suitable for promotion and application in industrial-scale production.

Description

Technical Field

[0001] This invention belongs to the field of homogenization heat treatment technology for ultra-large 2219 aluminum alloy round ingots, and relates to a homogenization heat treatment method for 2219 aluminum alloy round ingots, particularly a homogenization heat treatment method for ultra-large 2219 aluminum alloy round ingots. Background Technology

[0002] With the rapid development of the aerospace industry in recent years, the increasing use of large-scale integral structures in aerospace and other fields has become an inevitable trend. The preparation of these materials relies heavily on large-scale, high-quality aluminum alloy ingots. Taking the 2219 alloy φ1420mm*3000 specification as an example, due to the large size of this alloy product, the ingot stress is greater, and traditional homogenization processes are insufficient to eliminate casting internal stress, leading to cracks at the head and tail. This results in a low yield and supply difficulties for this specification. 2219 aluminum alloy belongs to the Al-Cu-Mn alloy category. When the copper content is 6.0%–6.5%, this type of alloy has a high recrystallization temperature and good heat resistance. However, during the semi-continuous casting process, non-equilibrium solidification forms coarse θ(Al2Cu) and T(CuMn2Al) ingots. 12 Cracking during the homogenization process can severely impact subsequent processing. While existing technologies have been studied, such as patent CN111270116 which describes a method for preparing ultra-large Al-Cu-Mg alloy ingots through melting and casting, the homogenization process is not described. Therefore, preventing ingot cracking during homogenization is currently the primary problem to be solved.

[0003] Therefore, how to provide a more suitable homogenization heat treatment method for ultra-large 2219 aluminum alloy round ingots to solve the problem of cracking that easily occurs during the homogenization process of existing large and ultra-large 2219 aluminum alloy round ingots is one of the urgent problems to be solved in this field. Summary of the Invention

[0004] In view of this, the technical problem to be solved by the present invention is to provide a homogenization heat treatment method for 2219 aluminum alloy round ingots, particularly a homogenization heat treatment method for ultra-large 2219 aluminum alloy round ingots. The homogenization heat treatment method provided by the present invention reduces casting internal stress, reduces the risk of cracking of large ingots due to uneven internal and external heating, and the process is simple and clear, highly controllable, and highly feasible on site, making it suitable for promotion and application in industrial-scale production.

[0005] This invention provides a homogenization heat treatment method for 2219 aluminum alloy round ingots, comprising the following steps:

[0006] 1) Multiple temperature measuring devices are set at different positions of aluminum alloy round ingots to obtain 2219 aluminum alloy round ingots to be homogenized and heat-treated.

[0007] 2) The 2219 aluminum alloy round ingot to be homogenized and heat-treated obtained in the above steps is placed in a heat treatment furnace for homogenization heat treatment and cooling process to obtain the 2219 aluminum alloy round ingot after homogenization heat treatment.

[0008] The homogenization heat treatment process includes the following steps:

[0009] 21) Set the first heating temperature on the heat treatment furnace. When the temperature measuring device reaches the first stage heat preservation temperature, adjust the first heating temperature previously set on the heat treatment furnace to the first stage heat preservation temperature, and then carry out the first stage heat preservation.

[0010] 22) Set a second heating temperature on the heat treatment furnace. When the temperature measuring device reaches the second stage holding temperature, adjust the previously set second heating temperature on the heat treatment furnace to the second stage holding temperature, and then carry out the second stage holding.

[0011] 23) Set the third heating temperature on the heat treatment furnace. When the temperature measuring device reaches the third stage heat preservation temperature, adjust the previously set third heating temperature on the heat treatment furnace to the third stage heat preservation temperature, and then carry out the third stage heat preservation.

[0012] 24) Set the fourth heating temperature on the heat treatment furnace. When the temperature measuring device reaches the fourth stage holding temperature, adjust the previously set fourth heating temperature on the heat treatment furnace to the fourth stage holding temperature, and then carry out the fourth stage holding.

[0013] Preferably, the 2219 aluminum alloy round ingot is an extra-large 2219 aluminum alloy round ingot;

[0014] The diameter of the 2219 aluminum alloy round ingot is φ630~φ1420;

[0015] The 2219 aluminum alloy comprises, by composition:

[0016] Si: 0.05%;

[0017] Fe: 0.10%–0.18%;

[0018] Cu: 5.90%–6.40%;

[0019] Mn: 0.25%–0.35%;

[0020] Mg: 0.015%;

[0021] Zn: 0.05%;

[0022] Ti: 0.02%–0.08%;

[0023] Zr: 0.11%–0.14%;

[0024] V: 0.06%~0.08%;

[0025] Al of the margin;

[0026] The insulation temperature of the first stage, the second stage, the third stage, and the fourth stage increases sequentially.

[0027] Preferably, the temperature measuring device includes a thermocouple;

[0028] The number of the plurality of temperature measuring devices includes 4 to 8;

[0029] The setting method includes remote setting;

[0030] The round ingot includes a cylindrical ingot;

[0031] The length of the round ingot is 6000-7000 mm.

[0032] Preferably, the two ends of the circular ingot along its length are the gate end and the lead end, respectively;

[0033] The temperature measuring device is located at the gate end of the round ingot, with two devices facing each other along the diameter of the circular cross-section of the round ingot.

[0034] The temperature measuring device is located at the tip of the round ingot, with two devices facing each other along the diameter of the round ingot's circular cross-section.

[0035] The angle between the line connecting the two temperature measuring devices at the gate end and the line connecting the two temperature measuring devices at the lead end is 0° to 90°.

[0036] Preferably, in step 21), when the temperature value measured by any one of the multiple temperature measuring devices reaches the lower limit of the first stage heat preservation temperature, the previously set first heating temperature is reduced to the first stage heat preservation temperature.

[0037] In step 21), when all the temperature values ​​measured by the multiple temperature measuring devices reach the lower limit of the first stage heat preservation temperature, the heat preservation time of the first stage heat preservation is calculated.

[0038] In step 22), when the temperature value measured by any one of the multiple temperature measuring devices reaches the lower limit of the second stage heat preservation temperature, the previously set second heating temperature is reduced to the second stage heat preservation temperature.

[0039] In step 22), when all the temperature values ​​measured by the multiple temperature measuring devices reach the lower limit of the second-stage heat preservation temperature, the heat preservation time of the second stage heat preservation is calculated.

[0040] Preferably, in step 23), when the temperature value measured by any one of the multiple temperature measuring devices reaches the lower limit of the third stage heat preservation temperature, the previously set third heating temperature is reduced to the third stage heat preservation temperature.

[0041] In step 23), when all the temperature values ​​measured by the multiple temperature measuring devices reach the lower limit of the third-stage heat preservation temperature, the heat preservation time of the third stage heat preservation is calculated.

[0042] In step 24), when the temperature value measured by any one of the multiple temperature measuring devices reaches the lower limit of the fourth stage heat preservation temperature, the previously set fourth heating temperature is reduced to the fourth stage heat preservation temperature.

[0043] In step 24), when all the temperature values ​​measured by the multiple temperature measuring devices reach the lower limit of the fourth stage insulation temperature, the insulation time of the fourth stage insulation begins to be calculated.

[0044] Preferably, the insulation temperature in the first stage is 435–445°C;

[0045] The initial heat preservation time is 7.6–8.4 hours.

[0046] The first heating temperature is 30°C higher than the first stage heat preservation temperature;

[0047] The second stage insulation temperature is 475–485℃;

[0048] The second stage of heat preservation lasts for 3.6–4.4 hours;

[0049] The second heating temperature is 30°C higher than the second stage heat preservation temperature.

[0050] Preferably, the third stage insulation temperature is 527–533°C;

[0051] The third stage of heat preservation lasts for 9.6–10.4 hours;

[0052] The third heating temperature is 10°C higher than the third stage heat preservation temperature.

[0053] Preferably, the fourth stage insulation temperature is 530–536°C;

[0054] The fourth stage of heat preservation time is 29.6–30.4 h or 37.6–38.4 h;

[0055] The fourth heating temperature is 2°C higher than the fourth stage heat preservation temperature;

[0056] When the diameter of the 2219 aluminum alloy round ingot is φ630~φ830, the holding time in the fourth stage is 29.6~30.4h;

[0057] When the diameter of the 2219 aluminum alloy round ingot is φ830~φ1420, the heat preservation time in the fourth stage is 37.6~38.4h.

[0058] Preferably, the time interval between the homogenization heat treatment and the cooling process is less than or equal to 15 seconds;

[0059] The cooling process specifically includes sequential air cooling, mist cooling, and water cooling;

[0060] The air cooling time is 55–65 minutes;

[0061] The time for fog cooling is 55–65 minutes;

[0062] The temperature of the cooled round ingot is less than or equal to 50°C.

[0063] This invention provides a homogenization heat treatment method for 2219 aluminum alloy round ingots, comprising the following steps: First, multiple temperature measuring devices are set at different positions on the aluminum alloy round ingot to obtain the 2219 aluminum alloy round ingot to be homogenized heat treatment; then, the 2219 aluminum alloy round ingot to be homogenized heat treatment obtained in the above steps is placed in a heat treatment furnace for homogenization heat treatment and cooling processes to obtain a homogenized heat treatment 2219 aluminum alloy round ingot; the homogenization heat treatment process includes the following steps: 21) A first heating temperature is set on the heat treatment furnace; when the temperature measuring devices reach the first stage holding temperature, the previously set first heating temperature on the heat treatment furnace is adjusted to the first stage holding temperature, then... The process involves several steps: 1) First-stage heat treatment; 22) Setting a second heating temperature on the heat treatment furnace; 3) Adjusting the previously set second heating temperature on the heat treatment furnace to the second-stage heat treatment temperature when the temperature measuring device reaches the third-stage heat treatment temperature; 4) Setting a fourth heating temperature on the heat treatment furnace; 5) Adjusting the previously set fourth heating temperature on the heat treatment furnace to the fourth-stage heat treatment temperature when the temperature measuring device reaches the fourth-stage heat treatment temperature; and 6) Performing the fourth-stage heat treatment. Compared with existing technologies, this invention creatively provides a homogenization heat treatment method for 2219 aluminum alloy round ingots with specific steps and a specific control process. This invention fully utilizes the effect of temperature on the re-dissolution of the eutectic phase by slowly heating it at the melting temperature of the low-melting-point eutectic phase. This ensures that the aluminum alloy ingot does not overheat, resulting in more complete re-dissolution of the low-melting-point eutectic phase, reducing casting internal stress, lowering the risk of cracking in large-sized ingots due to uneven internal and external heating, and eliminating the formation of coarse θ(Al₂Cu) and T(CuMn₂Al) particles during non-equilibrium solidification in semi-continuous casting. 12 This provides high-quality raw materials for subsequent forging, rolling, and other processing methods. Furthermore, the process is simple and clear, highly controllable, and easily executable on-site, making it suitable for promotion and application in industrial-scale production. Attached Figure Description

[0064] Figure 1 A photograph of the actual installation of the thermocouple on the extra-large 2219 aluminum alloy round ingot provided for this invention.

[0065] Figure 2 A schematic diagram of the thermocouple setup provided by the present invention;

[0066] Figure 3 Metallographic image of an extra-large 2219 aluminum alloy round ingot before homogenization;

[0067] Figure 4Metallographic image of an extra-large 2219 aluminum alloy round ingot after undergoing conventional homogenization process;

[0068] Figure 5 Metallographic image of an extra-large 2219 aluminum alloy round ingot after applying the homogenization process of this invention;

[0069] Figure 6 This is a metallographic image of an ultra-large 2219 aluminum alloy round ingot after homogenization heat treatment according to Embodiment 1 of the present invention. Detailed Implementation

[0070] To further understand the present invention, preferred embodiments of the present invention are described below in conjunction with examples. However, it should be understood that these descriptions are only for further illustrating the features and advantages of the present invention, and not for limiting the scope of the claims.

[0071] There are no particular restrictions on the source of any raw materials used in this invention; they can be purchased from the market or prepared using conventional methods known to those skilled in the art.

[0072] There are no particular restrictions on the purity of any of the raw materials used in this invention. However, this invention preferably uses industrial-grade pure materials or materials with the purity requirements commonly used in the preparation of 2219 aluminum alloy.

[0073] All raw materials of this invention are conventional in the field, and each brand name and abbreviation is clear and distinct in its relevant application. Those skilled in the art can purchase them from the market or prepare them by conventional methods based on the brand name, abbreviation and corresponding application.

[0074] The processes used in this invention are all commonly referred to in the field. The specific steps and conventional parameters of each abbreviation are clear and well-defined in their respective fields. Those skilled in the art can implement them using conventional methods based on the abbreviations.

[0075] This invention provides a homogenization heat treatment method for 2219 aluminum alloy round ingots, comprising the following steps:

[0076] 1) Multiple temperature measuring devices are set at different positions of aluminum alloy round ingots to obtain 2219 aluminum alloy round ingots to be homogenized and heat-treated.

[0077] 2) The 2219 aluminum alloy round ingot to be homogenized and heat-treated obtained in the above steps is placed in a heat treatment furnace for homogenization heat treatment and cooling process to obtain the 2219 aluminum alloy round ingot after homogenization heat treatment.

[0078] The homogenization heat treatment process includes the following steps:

[0079] 21) Set the first heating temperature on the heat treatment furnace. When the temperature measuring device reaches the first stage heat preservation temperature, adjust the first heating temperature previously set on the heat treatment furnace to the first stage heat preservation temperature, and then carry out the first stage heat preservation.

[0080] 22) Set a second heating temperature on the heat treatment furnace. When the temperature measuring device reaches the second stage holding temperature, adjust the previously set second heating temperature on the heat treatment furnace to the second stage holding temperature, and then carry out the second stage holding.

[0081] 23) Set the third heating temperature on the heat treatment furnace. When the temperature measuring device reaches the third stage heat preservation temperature, adjust the previously set third heating temperature on the heat treatment furnace to the third stage heat preservation temperature, and then carry out the third stage heat preservation.

[0082] 24) Set the fourth heating temperature on the heat treatment furnace. When the temperature measuring device reaches the fourth stage holding temperature, adjust the previously set fourth heating temperature on the heat treatment furnace to the fourth stage holding temperature, and then carry out the fourth stage holding.

[0083] In this invention, the insulation temperature of the first stage, the insulation temperature of the second stage, the insulation temperature of the third stage, and the insulation temperature of the fourth stage are preferably increased sequentially.

[0084] The present invention first sets multiple temperature measuring devices at different positions of aluminum alloy round ingots to obtain 2219 aluminum alloy round ingots to be homogenized by heat treatment.

[0085] In this invention, the 2219 aluminum alloy round ingot is preferably an extra-large 2219 aluminum alloy round ingot.

[0086] In this invention, the diameter of the 2219 aluminum alloy round ingot is preferably φ630~φ1420, more preferably φ730~φ1320, more preferably φ830~φ1220, and even more preferably φ930~φ1120.

[0087] In this invention, the 2219 aluminum alloy preferably comprises, by composition:

[0088] Si: 0.05%;

[0089] Fe: 0.10%–0.18%;

[0090] Cu: 5.90%–6.40%;

[0091] Mn: 0.25%–0.35%;

[0092] Mg: 0.015%;

[0093] Zn: 0.05%;

[0094] Ti: 0.02%–0.08%;

[0095] Zr: 0.11%–0.14%;

[0096] V: 0.06%~0.08%;

[0097] Al is the margin.

[0098] In this invention, in the 2219 aluminum alloy, the individual impurity is preferably less than or equal to 0.05%, and the total amount of impurities is preferably less than or equal to 0.15%.

[0099] In this invention, the amount of Si added is preferably 0.05%.

[0100] In this invention, the amount of Fe added is preferably 0.10% to 0.18%, more preferably 0.11% to 0.17%, more preferably 0.12% to 0.16%, and even more preferably 0.13% to 0.15%.

[0101] In this invention, the amount of Cu added is preferably 5.90% to 6.40%, more preferably 6.00% to 6.30%, and even more preferably 6.10% to 6.20%.

[0102] In this invention, the amount of Mn added is preferably 0.25% to 0.35%, more preferably 0.27% to 0.33%, and even more preferably 0.29% to 0.31%.

[0103] In this invention, the amount of Mg added is preferably 0.015%.

[0104] In this invention, the amount of Zn added is preferably 0.05%.

[0105] In this invention, the amount of Ti added is preferably 0.02% to 0.08%, more preferably 0.03% to 0.07%, and even more preferably 0.04% to 0.06%.

[0106] In this invention, the amount of Zr added is preferably 0.11% to 0.14%, more preferably 0.115% to 0.135%, and even more preferably 0.12% to 0.13%.

[0107] In this invention, the amount of V added is preferably 0.06% to 0.08%, more preferably 0.064% to 0.076%, and even more preferably 0.068% to 0.072%.

[0108] The present invention further places the 2219 aluminum alloy round ingot to be homogenized heat treatment obtained in the above steps into a heat treatment furnace for homogenization heat treatment and cooling process, and then obtains the 2219 aluminum alloy round ingot after homogenization heat treatment.

[0109] In this invention, the homogenization heat treatment process preferably includes the following steps:

[0110] 21) Set the first heating temperature on the heat treatment furnace. When the temperature measuring device reaches the first stage heat preservation temperature, adjust the first heating temperature previously set on the heat treatment furnace to the first stage heat preservation temperature, and then carry out the first stage heat preservation.

[0111] 22) Set a second heating temperature on the heat treatment furnace. When the temperature measuring device reaches the second stage holding temperature, adjust the previously set second heating temperature on the heat treatment furnace to the second stage holding temperature, and then carry out the second stage holding.

[0112] 23) Set the third heating temperature on the heat treatment furnace. When the temperature measuring device reaches the third stage heat preservation temperature, adjust the previously set third heating temperature on the heat treatment furnace to the third stage heat preservation temperature, and then carry out the third stage heat preservation.

[0113] 24) Set the fourth heating temperature on the heat treatment furnace. When the temperature measuring device reaches the fourth stage holding temperature, adjust the previously set fourth heating temperature on the heat treatment furnace to the fourth stage holding temperature, and then carry out the fourth stage holding.

[0114] The present invention first sets a first heating temperature on the heat treatment furnace. When the temperature measuring device reaches the first stage heat preservation temperature, the first heating temperature previously set on the heat treatment furnace is adjusted to the first stage heat preservation temperature, and then the first stage heat preservation is performed.

[0115] In this invention, in step 21), when the temperature value of any one of the multiple temperature measuring devices reaches the lower limit of the first stage heat preservation temperature, it is preferable to reduce the previously set first heating temperature to the first stage heat preservation temperature.

[0116] In this invention, in step 21), when all the temperature values ​​measured by the multiple temperature measuring devices reach the lower limit of the first stage heat preservation temperature, it is preferable to start calculating the heat preservation time of the first stage heat preservation.

[0117] In this invention, the heat preservation temperature of the first stage is preferably 435-445℃, more preferably 437-443℃, and even more preferably 439-441℃.

[0118] In this invention, the heat preservation time in the first stage is preferably 7.6 to 8.4 hours, more preferably 7.7 to 8.3 hours, more preferably 7.8 to 8.2 hours, and even more preferably 7.9 to 8.1 hours.

[0119] In this invention, the first heating temperature is preferably increased by 30°C compared to the first stage heat preservation temperature.

[0120] The present invention then sets a second heating temperature on the heat treatment furnace. When the temperature measuring device reaches the second stage holding temperature, the previously set second heating temperature on the heat treatment furnace is adjusted to the second stage holding temperature, and then the second stage holding is performed.

[0121] In this invention, in step 22), when the temperature value of any one of the multiple temperature measuring devices reaches the lower limit of the second stage heat preservation temperature, it is preferable to reduce the previously set second heating temperature to the second stage heat preservation temperature.

[0122] In this invention, in step 22), when all the temperature values ​​measured by the multiple temperature measuring devices reach the lower limit of the second-stage heat preservation temperature, it is preferable to start calculating the heat preservation time of the second-stage heat preservation.

[0123] In this invention, the second stage heat preservation temperature is preferably 475-485℃, more preferably 477-483℃, and even more preferably 479-481℃.

[0124] In this invention, the heat preservation time in the second stage is preferably 3.6 to 4.4 hours, more preferably 3.7 to 4.3 hours, more preferably 3.8 to 4.2 hours, and even more preferably 3.9 to 4.1 hours.

[0125] In this invention, the second heating temperature is preferably increased by 30°C in the second stage of heat preservation.

[0126] The present invention further sets a third heating temperature on the heat treatment furnace. When the temperature measuring device reaches the third stage heat preservation temperature, the previously set third heating temperature on the heat treatment furnace is adjusted to the third stage heat preservation temperature, and then the third stage heat preservation is carried out.

[0127] In this invention, in step 23), when the temperature value of any one of the multiple temperature measuring devices reaches the lower limit of the third stage heat preservation temperature, it is preferable to lower the previously set third heating temperature to the third stage heat preservation temperature.

[0128] In this invention, in step 23), when all the temperature values ​​measured by the multiple temperature measuring devices reach the lower limit of the third-stage heat preservation temperature, it is preferable to start calculating the heat preservation time of the third-stage heat preservation.

[0129] In this invention, the third stage heat preservation temperature is preferably 527-533℃, more preferably 528-532℃, and even more preferably 529-531℃.

[0130] In this invention, the heat preservation time in the third stage is preferably 9.6 to 10.4 hours, more preferably 9.7 to 10.3 hours, more preferably 9.8 to 10.2 hours, and even more preferably 9.9 to 10.1 hours.

[0131] In this invention, the third heating temperature is preferably increased by 10°C in the third stage heat preservation temperature.

[0132] Finally, the invention sets a fourth heating temperature on the heat treatment furnace. When the temperature measuring device reaches the fourth stage holding temperature, the previously set fourth heating temperature on the heat treatment furnace is adjusted to the fourth stage holding temperature, and then the fourth stage holding is performed.

[0133] In this invention, in step 24), when the temperature value of any one of the multiple temperature measuring devices reaches the lower limit of the fourth stage heat preservation temperature, it is preferable to reduce the previously set fourth heating temperature to the fourth stage heat preservation temperature.

[0134] In this invention, in step 24), when all the temperature values ​​measured by the multiple temperature measuring devices reach the lower limit of the fourth stage heat preservation temperature, it is preferable to start calculating the heat preservation time of the fourth stage heat preservation.

[0135] In this invention, the fourth stage heat preservation temperature is preferably 530-536℃, more preferably 531-535℃, and even more preferably 532-534℃.

[0136] In this invention, the heat preservation time in the fourth stage is preferably 29.6–30.4 h or 37.6–38.4 h, more preferably 29.7–30.3 h or 37.7–38.3 h, more preferably 29.8–30.2 h or 37.6–38.2 h, more preferably 29.9–30.2 h or 37.8–38.2 h, and even more preferably 30.0–30.1 h or 37.9–38.1 h.

[0137] In this invention, the fourth heating temperature is preferably increased by 2°C compared to the fourth stage heat preservation temperature.

[0138] In this invention, when the diameter of the 2219 aluminum alloy round ingot is φ630~φ830, the holding time in the fourth stage is preferably 29.6~30.4h, more preferably 29.7~30.3h, more preferably 29.8~30.2h, and even more preferably 29.9~30.1h.

[0139] In this invention, when the diameter of the 2219 aluminum alloy round ingot is φ830~φ1420, the preferred holding time for the fourth stage is 37.6~38.4h, more preferably 37.7~38.3h, 37.8~38.2h, or 37.9~38.1h. Specifically, the holding time is 30h for 630~830mm ingots and 38h for ingots larger than 830mm ingots.

[0140] In this invention, the temperature measuring device preferably includes a thermocouple.

[0141] In this invention, the number of the plurality of temperature measuring devices preferably includes 4 to 8, more preferably 5 to 7.

[0142] In this invention, the preferred method of setting the device includes remote setting.

[0143] In this invention, the round ingot preferably includes a cylindrical ingot.

[0144] In this invention, the length of the round ingot is preferably 6000-7000 mm, more preferably 6200-6800 mm, and most preferably 6400-6600 mm.

[0145] In this invention, the two ends of the round ingot along its length are preferably the gating end and the lead end, respectively.

[0146] In this invention, the temperature measuring device is preferably located at the gate end of the round ingot, with two devices facing each other along the diameter direction of the circular cross-section of the round ingot.

[0147] In this invention, the preferred temperature measuring device is located at the tip of the round ingot, with two devices facing each other along the diameter of the round ingot's circular cross-section.

[0148] Specifically, a diameter is drilled at the thermocouple installation location (the ingot lead end and the gate end). Insert and secure the thermocouple through a round hole with a depth of ≥30mm.

[0149] See Figure 1 , Figure 1 A photograph of the actual installation of the thermocouple on the extra-large 2219 aluminum alloy round ingot provided for this invention.

[0150] In this invention, the angle between the line connecting the two temperature measuring devices at the gate end and the line connecting the two temperature measuring devices at the lead end is preferably 0° to 90°, more preferably 20° to 70°, and even more preferably 40° to 50°.

[0151] In this invention, the interval between the homogenization heat treatment and the cooling process is preferably less than or equal to 15 seconds, more preferably less than or equal to 14 seconds, and more preferably less than or equal to 13 seconds.

[0152] In this invention, the cooling process preferably includes sequentially performing air cooling, mist cooling, and water cooling.

[0153] In this invention, the air cooling time is preferably 55-65 min, more preferably 57-63 min, and even more preferably 59-61 min.

[0154] In this invention, the fog cooling time is preferably 55-65 min, more preferably 57-63 min, and even more preferably 59-61 min.

[0155] In this invention, the preferred water cooling time is water cooling to room temperature.

[0156] In this invention, the temperature of the cooled round ingot is preferably less than or equal to 50°C, more preferably less than or equal to 45°C, and even more preferably less than or equal to 40°C.

[0157] In this invention, the apparatus for homogenization heat treatment is preferably a homogenization heat treatment furnace, specifically a 50-ton aluminum ingot homogenizing furnace (designed and configured according to the requirements of Class I furnace and Type A instrumentation in AMS2750E, capable of meeting the performance test requirements such as TUS and SAT in relevant AMS2750E standards). This 50-ton aluminum ingot homogenizing furnace can be manufactured by Suzhou Xinchangguang Thermal Energy Technology Co., Ltd.

[0158] In this invention, the cooling device is preferably a 50-ton cooling furnace, specifically a 50-ton cooling furnace produced by Suzhou Xinchang Photovoltaic Thermal Energy Technology Co., Ltd.

[0159] This invention provides a complete and detailed overall technical solution to ensure the stability and controllability of the homogenization heat treatment process for 2219 aluminum alloy round ingots, further improving the overall effect of homogenization heat treatment for 2219 aluminum alloy round ingots. Specifically, the homogenization heat treatment method for ultra-large 2219 aluminum alloy round ingots may include the following:

[0160] (1) Heating is performed using material temperature; the thermocouple is set up as follows: Figure 2 As shown.

[0161] See Figure 2 , Figure 2 This is a schematic diagram of the thermocouple setup provided by the present invention.

[0162] (2) Heat equalization is carried out by differential heating, and four-stage heat equalization is used.

[0163] Specifically, when the temperature reading of a thermocouple reaches the lower limit of the insulation temperature, the furnace gas temperature must be adjusted to the insulation temperature.

[0164] Specifically, the insulation program can only be started and the insulation time can only be calculated when the temperature readings of the four thermocouples reach the lower limit of the insulation temperature.

[0165] Specifically, after the homogenization is complete, the ingot is transferred to the cooling furnace using an ingot transfer trolley. The maximum allowable transfer time is 15 seconds.

[0166] Specifically, the cooling process is as follows: first, strong air cooling for 60 minutes, then mist cooling for 60 minutes, and finally water cooling until the ingot temperature drops below 50°C.

[0167] Specifically, the difference between different specifications of this 2219 alloy lies in the different heat preservation times for the four levels: 38 hours for φ830 and 30 hours for φ630~830.

[0168] See Figure 3 , Figure 3 Metallographic image of an extra-large 2219 aluminum alloy round ingot before homogenization.

[0169] See Figure 4 , Figure 4 Metallographic image of an extra-large 2219 aluminum alloy round ingot after undergoing conventional homogenization process.

[0170] See Figure 5 , Figure 5 Metallographic image of an extra-large 2219 aluminum alloy round ingot after applying the homogenization process of this invention.

[0171] Depend on Figures 3-5 It can be seen that before homogenization, there are a large number of low-melting-point eutectic phases; while after homogenization by the general method, low-melting-point eutectic phases still exist; after homogenization using the present invention, the low-melting-point eutectic phases are more fully dissolved.

[0172] The present invention provides a homogenization heat treatment method for ultra-large 2219 aluminum alloy round ingots. This method involves specific steps and controlled processes for homogenizing 2219 aluminum alloy round ingots. By slowly heating at the melting temperature of the low-melting-point eutectic phase, the invention fully utilizes the effect of temperature on the dissolution of the eutectic phase. This ensures that the aluminum alloy ingot does not overheat, resulting in more complete dissolution of the low-melting-point eutectic phase, reducing casting internal stress, lowering the risk of cracking in large ingots due to uneven internal and external heating, and eliminating the formation of coarse θ(Al₂Cu) and T(CuMn₂Al) particles during non-equilibrium solidification in semi-continuous casting. 12 This provides high-quality raw materials for subsequent forging, rolling, and other processing methods. Furthermore, the process is simple and clear, highly controllable, and easily executable on-site, making it suitable for promotion and application in industrial-scale production.

[0173] To further illustrate the present invention, the following describes in detail a homogenization heat treatment method for 2219 aluminum alloy round ingots provided by the present invention with reference to embodiments. However, it should be understood that these embodiments are implemented under the premise of the technical solution of the present invention, and detailed implementation methods and specific operation processes are given only to further illustrate the features and advantages of the present invention, and are not intended to limit the scope of the claims of the present invention. The scope of protection of the present invention is not limited to the following embodiments.

[0174] Example 1

[0175] use Figure 1 and Figure 2 Thermocouple settings in the system.

[0176] The specification of the 2219 aluminum alloy round ingot is φ1420mm.

[0177] The main chemical composition of 2219 aluminum alloy round ingots is shown in Table 1.

[0178] See Table 1, which shows the main chemical composition of the 2219 aluminum alloy round ingot provided by this invention.

[0179] Table 1

[0180]

[0181] The 2219 aluminum alloy round ingots were placed in a heat treatment furnace for homogenization heat treatment. The homogenization was carried out by differential heating, using a four-stage homogenization process.

[0182] ① When starting to heat up, the furnace gas temperature is set to 470℃. When all the thermocouples reach 435℃, the temperature is maintained at 440℃ for 8 hours. ② The furnace gas temperature is set to 510℃ for heating. When all the thermocouples reach 475℃, the temperature is changed to 480℃ for 4 hours. ③ The furnace gas temperature is set to 540℃ for heating. When all the thermocouples reach 527℃, the temperature is changed to 530℃ for 10 hours. ④ The furnace gas temperature is set to 535℃ for heating. When all the thermocouples reach 530℃, the temperature is changed to 533℃ for 38 hours.

[0183] See Table 2, which describes the specific heat treatment process for the four-stage homogenization provided in Embodiment 1 of the present invention.

[0184] Table 2

[0185]

[0186] After homogenization is complete, the ingot is transferred to the cooling furnace using an ingot transfer trolley. The maximum allowable transfer time is 15 seconds.

[0187] Cooling process: First, use strong air cooling for 60 minutes, then mist cooling for 60 minutes, and finally water cooling for 30 minutes to cool the ingot down to below 50°C.

[0188] The ultra-large 2219 aluminum alloy round ingot prepared by homogenization and heat treatment in Example 1 of the present invention was characterized.

[0189] See Figure 6 , Figure 6 This is a metallographic image of an ultra-large 2219 aluminum alloy round ingot after homogenization heat treatment according to Embodiment 1 of the present invention.

[0190] Metallographic results (2219 alloy - φ1420mm) show that after etching, the sample was observed at 200x magnification, and the microstructure showed no overheating, with a grain size of 170um.

[0191] The above provides a detailed description of a homogenization heat treatment method for ultra-large 2219 aluminum alloy round ingots provided by this invention. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the above embodiments are merely for the purpose of helping to understand the method and core ideas of this invention, including the best mode, and also to enable any person skilled in the art to practice this invention, including manufacturing and using any device or system, and implementing any combined method. It should be noted that for those skilled in the art, several improvements and modifications can be made to this invention without departing from the principles of this invention, and these improvements and modifications also fall within the protection scope of the claims of this invention. The scope of protection of this patent is defined by the claims and may include other embodiments that can be conceived by those skilled in the art. If these other embodiments have structural elements that are not different from the textual description of the claims, or if they include equivalent structural elements that are not substantially different from the textual description of the claims, then these other embodiments should also be included within the scope of the claims.

Claims

1. A method of homogenizing heat treatment of a 2219 aluminum alloy round ingot, characterized by, The method comprises the following steps: 1) setting multiple temperature measuring devices at different positions of an aluminum alloy round ingot to obtain a 2219 aluminum alloy round ingot to be homogenized; 2) placing the 2219 aluminum alloy round ingot to be homogenized obtained in the above step into a heat treatment furnace to perform a homogenization heat treatment and a cooling process, and obtaining a 2219 aluminum alloy round ingot after homogenization heat treatment; The homogenization heat treatment process comprises the following steps: 21) setting a first heating temperature on the heat treatment furnace, adjusting the first heating temperature previously set on the heat treatment furnace to a first stage holding temperature when the temperature measuring device reaches the first stage holding temperature, and then performing first stage holding; The first stage holding temperature is 435-445℃; The first stage holding time is 7.6-8.4h; The first heating temperature is 30℃ higher than the first stage holding temperature; 22) setting a second heating temperature on the heat treatment furnace, adjusting the second heating temperature previously set on the heat treatment furnace to a second stage holding temperature when the temperature measuring device reaches the second stage holding temperature, and then performing second stage holding; The second stage holding temperature is 475-485℃; The second stage holding time is 3.6-4.4h; The second heating temperature is 30℃ higher than the second stage holding temperature; 23) setting a third heating temperature on the heat treatment furnace, adjusting the third heating temperature previously set on the heat treatment furnace to a third stage holding temperature when the temperature measuring device reaches the third stage holding temperature, and then performing third stage holding; The third stage holding temperature is 527-533℃; The third stage holding time is 9.6-10.4h; The third heating temperature is 10℃ higher than the third stage holding temperature; 24) setting a fourth heating temperature on the heat treatment furnace, adjusting the fourth heating temperature previously set on the heat treatment furnace to a fourth stage holding temperature when the temperature measuring device reaches the fourth stage holding temperature, and then performing fourth stage holding; The fourth stage holding temperature is 530-536℃; The fourth stage holding time is 29.6-30.4h or 37.6-38.4h; The fourth heating temperature is 2℃ higher than the fourth stage holding temperature.

2. The homogenization heat treatment method according to claim 1, characterized by, The 2219 aluminum alloy round ingot is a super-large specification 2219 aluminum alloy round ingot; The diameter of the 2219 aluminum alloy round ingot is φ630-φ1420; The 2219 aluminum alloy comprises the following components: Si: 0.05%; Fe: 0.10%-0.18%; Cu: 5.90%-6.40%; Mn: 0.25%-0.35%; Mg: 0.015%; Zn: 0.05%; Ti: 0.02%-0.08%; Zr： 0.11%~0.14%； V： 0.06%~0.08%； balance Al; The first stage holding temperature, the second stage holding temperature, the third stage holding temperature and the fourth stage holding temperature increase in turn.

3. The homogenization heat treatment method according to claim 1, characterized by, The temperature measuring device comprises a thermocouple; The number of the multiple temperature measuring devices comprises 4-8; The setting mode comprises remote setting; The round ingot comprises a cylindrical ingot; The length of the round ingot is 6000-7000 mm.

4. The homogenization heat treatment method according to claim 3, characterized by, The two ends of the length direction of the round ingot are a gate end and a head end respectively; The temperature measuring device is arranged at the gate end of the round ingot, and two temperature measuring devices are arranged in the round ingot in a diametrically opposite contact manner along the diameter direction of the circular cross section of the round ingot; The temperature measuring device is arranged at the head end of the round ingot, and two temperature measuring devices are arranged in the round ingot in a diametrically opposite contact manner along the diameter direction of the circular cross section of the round ingot; The included angle between the connecting line of the two temperature measuring devices arranged at the gate end and the connecting line of the two temperature measuring devices arranged at the head end is 0-90°.

5. The homogenization heat treatment method according to claim 1, characterized by, In the step 21), when the temperature measuring value of any one of the multiple temperature measuring devices reaches the lower limit of the first stage holding temperature, the previously set first heating temperature is reduced to the first stage holding temperature; In the step 21), when the temperature measuring values of all the multiple temperature measuring devices reach the lower limit of the first stage holding temperature, the holding time of the first stage holding is started to be calculated.

6. The homogenization heat treatment method according to claim 1, characterized by, In the step 22), when the temperature measuring value of any one of the multiple temperature measuring devices reaches the lower limit of the second stage holding temperature, the previously set second heating temperature is reduced to the second stage holding temperature; In the step 22), when the temperature measuring values of all the multiple temperature measuring devices reach the lower limit of the second stage holding temperature, the holding time of the second stage holding is started to be calculated.

7. The homogenization heat treatment method according to claim 1, characterized by, In the step 23), when the temperature measuring value of any one of the multiple temperature measuring devices reaches the lower limit of the third stage holding temperature, the previously set third heating temperature is reduced to the third stage holding temperature; In the step 23), when the temperature measuring values of all the multiple temperature measuring devices reach the lower limit of the third stage holding temperature, the holding time of the third stage holding is started to be calculated.

8. The homogenization heat treatment method according to claim 1, characterized by, In the step 24), when the temperature measuring value of any one of the multiple temperature measuring devices reaches the lower limit of the fourth stage holding temperature, the previously set fourth heating temperature is reduced to the fourth stage holding temperature; In the step 24), when the temperature measuring values of all the multiple temperature measuring devices reach the lower limit of the fourth stage holding temperature, the holding time of the fourth stage holding is started to be calculated.

9. The homogenization heat treatment method according to claim 1, characterized by, When the diameter of the 2219 aluminum alloy round ingot is φ630-φ830, the time of the fourth stage holding is 29.6-30.4 h; When the diameter of the 2219 aluminum alloy round ingot is φ830-φ1420, the time of the fourth stage holding is 37.6-38.4 h.

10. The homogenization heat treatment method according to claim 1, characterized by, The interval time between the homogenization heat treatment and the cooling process is less than or equal to 15 seconds; The cooling process specifically includes sequentially performing air cooling, fog cooling and water cooling; The time of the air cooling is 55-65 min; The time of the fog cooling is 55-65 min; The temperature of the cooled round ingot is less than or equal to 50℃.

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