A graded extrusion processing method with segmented temperature setting

Abstract

This invention provides a staged extrusion processing method with segmented temperature settings. The method involves segmenting and coordinating the temperatures of the extruder's insulation cylinder, cast rod, die, and extrusion speed. In the initial stage, low-speed extrusion is performed while maintaining high temperatures in the insulation cylinder, cast rod, and die. In the subsequent stage, high-speed extrusion is performed while maintaining low temperatures in these three stages, achieving a constant-temperature extrusion process with a stable extrusion outlet temperature throughout the entire process. This extrusion method, by segmenting and coordinating the temperatures of the extruder's insulation cylinder, cast rod, die, and extrusion speed, significantly improves the material's mechanical properties, quality stability, and production efficiency. It features low cost, reliable and easily controllable process, and low equipment requirements, making it suitable for the mass production of complex thin-walled aluminum alloy profiles.

Description

Technical Field

[0001] This invention relates to the field of aluminum alloy profile processing technology, and in particular to a graded extrusion processing method with segmented temperature settings, especially a method for extruding complex thin-walled aluminum alloy profiles. Background Technology

[0002] Aluminum alloys are formed by adding one or more metallic elements to aluminum. They not only possess the characteristics of pure aluminum, such as low density, corrosion resistance, and strong castability, but also exhibit significantly increased strength and hardness compared to pure aluminum. Besides solid solution strengthening, some aluminum alloys can also be strengthened by heat treatment. After heat treatment, they possess moderate strength, high impact toughness, and are notch-insensitive. The tensile strength of some aluminum alloys can exceed 600 MPa, and their specific strength (strength to density ratio) surpasses that of certain alloy steels. Based on these excellent material properties, aluminum alloys are widely used as structural materials in construction, transportation, and sports, especially in the transportation industry. For example, in high-speed trains, subway trains, double-decker trains, and passenger and freight vehicles, complex thin-walled, hollow, large aluminum alloy panel profiles are needed to replace steel in mechanical parts, achieving lightweighting of transportation vehicles.

[0003] Currently, in the extrusion process of complex thin-walled aluminum alloy profiles, the extrusion temperature (insulation cylinder temperature, casting rod temperature and die temperature) and extrusion speed of the extruder are mostly set to the same working mode in the front and back sections. This can easily cause extrusion cracks on the profile surface, significantly reduce the mechanical properties of the profile, destroy the structural continuity, and result in poor material properties and unreliable product quality due to the extrusion temperature and speed. In addition, the production efficiency is low. Summary of the Invention

[0004] Based on this, the present invention provides a staged extrusion processing method with segmented temperature settings to improve the material mechanical properties, product quality and production efficiency of extrusion processing of thin-walled aluminum alloy profiles.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows: a staged extrusion processing method with segmented temperature settings, wherein the temperature of the insulation cylinder, the temperature of the casting rod, the temperature of the die, and the extrusion speed of the extruder are set and matched in segments: in the first stage of extrusion processing, a low-speed extrusion processing is configured under the condition of maintaining a high temperature of the insulation cylinder, the high temperature of the casting rod, and the high temperature of the die; in the second stage of extrusion processing, a high-speed extrusion processing is configured under the condition of maintaining a low temperature of the insulation cylinder, the low temperature of the casting rod, and the low temperature of the die, thereby achieving constant-temperature extrusion processing with a stable extrusion outlet temperature throughout the entire extrusion process.

[0006] Furthermore, the extrusion process also includes performing a graded aging treatment on the formed complex thin-walled aluminum alloy profile, first at high temperature for a short time and then at low temperature for a long time. Through the graded aging treatment, the mechanical properties of the profile are improved, so that the material properties of the profile are effectively guaranteed.

[0007] Furthermore, the graded aging process includes at least two aging processes, wherein the first aging temperature is higher than the second aging temperature and the first aging time is shorter than the second aging time.

[0008] Furthermore, the extrusion processing method also includes heating the mold in the initial stage of extrusion and then cooling the mold to avoid the mold temperature being too high in the later stage, which would affect product quality, mold service life, etc.

[0009] Furthermore, the temperature of the insulation cylinder is set in segments, and the temperature of the insulation cylinder is set to decrease linearly along the processing direction of the extruder, so that the temperature of the insulation cylinder changes stably.

[0010] Furthermore, the heating temperature of the casting rod is set in segments, and the heating temperature of the casting rod is set to decrease linearly along the processing direction of the extruder, so that the temperature of the casting rod changes stably.

[0011] Furthermore, the extrusion speed is set in segments, and the extrusion speed is set to increase linearly along the processing direction of the extruder, so that the extrusion speed changes stably.

[0012] Furthermore, depending on the material of the casting rod and / or the cross-sectional shape and area of ​​the complex thin-walled aluminum alloy profile, different insulation cylinder temperatures, casting rod heating temperatures, mold temperatures, and extrusion speeds are set in stages.

[0013] Furthermore, the extrusion processing method includes the following steps:

[0014] S10. In the pre-extrusion stage, under the conditions of maintaining high temperatures in the insulation cylinder, casting rod, and die, low-speed extrusion is configured.

[0015] S20. In the later stage of extrusion processing, high-speed extrusion processing is configured under the conditions of keeping the temperature of the insulation cylinder, the temperature of the casting rod, and the temperature of the die low;

[0016] S30. First-level aging treatment, set high aging temperature and short aging time;

[0017] S40. Second season time-sensitive processing: set low time-sensitive temperature and long time-sensitive period.

[0018] Furthermore, various process parameters such as extrusion temperature, extrusion speed, and aging treatment are set in stages, including: Staged temperature settings for the insulation cylinder: the front section temperature is set to 440–460℃, and the rear section temperature is set to 410–430℃; Staged temperature settings for the casting rod: the front section temperature is set to 525–555℃, and the rear section temperature is set to 495–525℃; Staged temperature settings for the die: the die temperature in the initial stage of extrusion is set to 470–490℃, and the die temperature in the stable stage of extrusion is set to 450–490℃. 470℃; Extrusion speed parameters are set in segments: the extrusion speed in the front section is set to 2.0~4.0mm / s, and the extrusion speed in the rear section is set to 4.0~6.0mm / s; Extrusion outlet temperature parameters are set: the extrusion outlet temperature is stabilized at 535~565℃; Aging process parameters are set in stages, first high temperature and short time, then low temperature and long time: the first stage aging temperature is set to 170~200℃, and the aging time is set to 1~4h; the second stage aging temperature is set to 140~180℃, and the aging time is set to 3~16h.

[0019] The technical advantages of the staged extrusion processing method with segmented temperature settings provided by this invention are at least reflected in the following aspects:

[0020] By segmenting and coordinating the temperature of the extruder's insulation cylinder, the heating temperature of the cast rod, and the extrusion speed, constant-temperature, high-speed extrusion is achieved in the extrusion process of complex thin-walled aluminum alloy profiles. This results in significant improvements in the dimensional accuracy, strength, toughness, corrosion resistance, and other mechanical properties of the produced profiles. During the extrusion process:

[0021] At the front end of the extruder, due to the high temperature of the insulation cylinder, the high temperature of the cast rod, the high temperature of the die, and the low extrusion speed, the cast rod becomes softer and has lower deformation resistance, making it easier to deform. At this time, the extrusion forming performance is greatly improved, the extrusion production efficiency is significantly improved, and the problem of excessive die stress and severe wear is avoided.

[0022] In the rear section of the extruder, based on the large amount of heat generated inside the profile due to the rapid extrusion at the front end, the temperature of the insulation cylinder, the temperature of the casting rod, and the temperature of the die are low in the rear section of the extrusion. The extrusion speed is high, which ensures that the temperature of the extrusion outlet is relatively stable throughout the entire extrusion process, avoiding the problem of cracks on the surface of the profile caused by excessive temperature. Attached Figure Description

[0023] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0024] Figure 1A flowchart illustrating an embodiment of a staged extrusion processing method with segmented temperature settings;

[0025] Figure 2 This is a flowchart illustrating an embodiment of a staged extrusion processing method with segmented temperature settings after setting process parameters. Detailed Implementation

[0026] To address the technical challenges in the extrusion processing of complex thin-walled aluminum alloy profiles, the inventors, drawing on long-term production practice and scientific research, discovered that existing extrusion technologies, operating with consistent extrusion temperature and speed at both the beginning and end of the process, suffer from several drawbacks. In the initial stage of the extrusion press, the low temperature and high speed result in insufficient heating of the cast rod, leading to high hardness and deformation resistance. This not only causes excessive stress on the die and severe wear but also results in low production efficiency. Moving from the beginning to the end of the press, as the extrusion process progresses, a large amount of heat accumulates inside the profile, causing the temperature in the deformation zone to rise. However, the extrusion speed in the later stage is too low, which is incompatible with the high profile temperatures, easily leading to extrusion cracks. Therefore, the rational setting and coordinated matching of extrusion temperature and speed at each stage of the extrusion process for complex thin-walled aluminum alloy profiles is crucial, significantly impacting the material's mechanical properties, quality stability, and production efficiency.

[0027] Based on the aforementioned production practices and scientific research, this invention provides a staged extrusion processing method with segmented temperature settings, particularly for the extrusion processing of complex thin-walled aluminum alloy profiles. The method involves segmenting and coordinating the temperatures of the extruder's insulation cylinder, casting rod, die, and extrusion speed: in the initial stage of extrusion, low-speed extrusion is performed while maintaining high temperatures for the insulation cylinder, casting rod, and die; in the later stage, high-speed extrusion is performed while maintaining low temperatures for the insulation cylinder, casting rod, and die. This achieves constant-temperature extrusion processing with stable extrusion outlet temperatures throughout the entire process, improving the material mechanical properties, quality, and production efficiency of complex thin-walled aluminum alloy profiles.

[0028] The specific embodiments of the present invention will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present invention, and not all embodiments. It should be noted that the following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use.

[0029] like Figure 1As shown in the embodiment of the graded extrusion processing method with segmented temperature settings provided by the present invention, the temperature of the insulation cylinder, the temperature of the cast rod, the temperature of the die, and the extrusion speed are set in segments. The temperature of the insulation cylinder, the temperature of the cast rod, and the temperature of the die are all set to be high in the first segment and low in the second segment, and the extrusion speed is set to be low in the first segment and high in the second segment. Furthermore, the insulation cylinder temperature, the temperature of the cast rod, the temperature of the die, and the extrusion speed of the extruder are coordinated and matched to achieve constant temperature extrusion processing with stable extrusion outlet temperature throughout the entire extrusion process: in the first segment, low-speed extrusion processing is configured under the condition of maintaining high insulation cylinder temperature, high cast rod temperature, and high die temperature; in the second segment, high-speed extrusion processing is configured under the condition of maintaining low insulation cylinder temperature, low cast rod temperature, and low die temperature.

[0030] The working principle and effect of this extrusion process for complex thin-walled aluminum alloy profiles:

[0031] In the extrusion stage, when the temperature of the insulation cylinder, the temperature of the cast rod, and the temperature of the die are all set at a high level, the cast rod becomes softer and easier to deform, and the extrudability of the cast rod is greatly improved. At this time, the extrusion speed is set at a low level, the deformation resistance is low, and the problem of excessive force on the die and rapid wear is avoided, which improves the effective service life of the die and significantly improves the production efficiency of extrusion processing.

[0032] In the later stages of extrusion, a large amount of heat is generated and the temperature rises due to rapid extrusion within the deformation zone. Therefore, the temperatures of the insulation cylinder, casting rod, and die in the later stages of extrusion are all set to be relatively low to avoid cracks on the profile surface caused by excessive temperature. At the same time, a higher extrusion speed is set to match the higher temperature of the casting rod, which improves the material mechanical properties and forming quality of the profile, and increases production efficiency.

[0033] like Figure 1 As shown, further, in some preferred embodiments, in order to improve the mechanical properties of the thin-walled aluminum alloy profile after extrusion forming, the extrusion processing method further includes performing a graded aging treatment on the formed complex thin-walled aluminum alloy profile, first at high temperature for a short time, and then at low temperature for a long time.

[0034] In specific implementation, the graded aging treatment includes at least two stages of aging treatment. The first stage aging temperature is higher than the second stage aging temperature, and the first stage aging time is shorter than the second stage aging time. In some specific embodiments, the aging process parameters are set in a graded manner, first at a high temperature for a short time and then at a low temperature for a long time: the first stage aging temperature is set to 170–200℃, and the aging time is set to 1–4 hours; the second stage aging temperature is set to 140–180℃, and the aging time is set to 3–16 hours.

[0035] Compared to existing single-temperature, single-time aging treatment technologies, complex thin-walled aluminum alloy profiles undergo a graded aging treatment consisting of a high-temperature short-time treatment followed by a low-temperature long-time treatment. This allows solute atoms to dissolve into the solid solution to the maximum extent possible without causing the alloy to melt, effectively improving the strength and toughness of the profiles and exhibiting better material mechanical properties.

[0036] In some preferred embodiments, to prevent the mold from overheating and wearing out too quickly, the extrusion process further includes heating the mold in the initial stage of extrusion and then cooling the mold to improve the effective service life of the mold.

[0037] In the specific implementation process, based on the segmented setting of the insulation cylinder temperature, the casting rod heating temperature, and the extrusion speed, the linear variation settings of the insulation cylinder temperature, the casting rod heating temperature, and the extrusion speed are implemented. Specifically, based on the segmented setting of the insulation cylinder temperature, the temperature of the insulation cylinder is set to decrease linearly along the processing direction of the extruder; based on the segmented setting of the casting rod heating temperature, the heating temperature of the casting rod is set to decrease linearly along the processing direction of the extruder; based on the segmented setting of the extrusion speed, the extrusion speed is set to increase linearly along the processing direction of the extruder.

[0038] The above implementation method, taking into account the extrusion molding characteristics of aluminum alloys, sets the temperature parameters of the insulation cylinder in segments. By setting the linear changes of the insulation cylinder temperature, the casting rod heating temperature and the extrusion speed, the extrusion process of thin-walled aluminum alloy profiles is kept stable.

[0039] Furthermore, based on the different materials of the casting rod and / or the different cross-sectional shapes and areas of complex thin-walled aluminum alloy profiles, different insulation cylinder temperatures, casting rod heating temperatures, die temperatures, and extrusion speeds are set in stages. In specific implementation, different insulation cylinder temperatures, casting rod heating temperatures, die temperatures, and extrusion speeds are set in stages according to the different contents of other metal elements in the aluminum alloy, so that the process parameters such as temperature and extrusion speed are matched with the material properties; similarly, based on the different cross-sectional shapes and areas of complex thin-walled aluminum alloy profiles, different insulation cylinder temperatures, casting rod heating temperatures, die temperatures, and extrusion speeds are set in stages to match the process parameters such as temperature and extrusion speed with the cross-sectional shape, thereby improving the production efficiency and product quality of complex thin-walled aluminum alloy profiles.

[0040] In the specific implementation process, the steps of using the provided staged extrusion processing method with segmented temperature settings include:

[0041] S10. In the pre-extrusion stage, under the conditions of maintaining high temperatures in the insulation cylinder, casting rod, and die, low-speed extrusion is configured.

[0042] S20. In the later stage of extrusion processing, high-speed extrusion processing is configured under the conditions of keeping the temperature of the insulation cylinder, the temperature of the casting rod, and the temperature of the die low;

[0043] S30. First-level aging treatment, set high aging temperature and short aging time;

[0044] S40. Second season time-sensitive processing: set low time-sensitive temperature and long time-sensitive period.

[0045] like Figure 2 As shown, in some embodiments, the parameters used in a staged extrusion process with segmented temperature settings are arranged according to the production sequence of the extrusion front end, extrusion back end, first-stage aging treatment, and second-stage aging treatment.

[0046] S10a. Pre-extrusion processing stage:

[0047] The temperature of the front section of the insulation cylinder is set to 440-460℃, and the temperature of the front section of the casting rod is set to 525-555℃; in the initial stage of extrusion, the die temperature is set to 470-490℃; the extrusion speed of the front section is set to 2.0-4.0 mm / s.

[0048] S20a. Post-extrusion processing stage:

[0049] The temperature of the rear section of the insulation cylinder is set to 410~430℃; the temperature of the rear section of the casting rod is set to 495~525℃; the temperature of the die in the extrusion stabilization stage is set to 450~470℃; and the extrusion speed in the rear section is set to 4.0~6.0mm / s.

[0050] S30a. First-level aging treatment:

[0051] The aging temperature is set to 170–200℃; the aging time is set to 1–4 hours.

[0052] S40a. Second-level aging treatment:

[0053] The aging temperature is set to 140–180℃; the aging time is set to 3–16 hours.

[0054] By segmenting and coordinating the temperature of the extruder's insulation cylinder, the heating temperature of the casting rod, and the extrusion speed, constant temperature and high speed extrusion is achieved in the extrusion processing of complex thin-walled aluminum alloy profiles. After graded aging treatment, the mechanical properties of the complex thin-walled aluminum alloy profiles produced are greatly improved, including dimensional accuracy, strength, toughness, and corrosion resistance.

[0055] In other embodiments, the extrusion processing parameters for complex thin-walled aluminum alloy profiles are set from the perspective of each component of the extruder as follows:

[0056] (1) Temperature segmentation parameters of the insulation cylinder:

[0057] The temperature of the front section of the insulation cylinder is set to 440-460℃, and the temperature of the rear section is set to 410-430℃.

[0058] (2) Casting rod temperature segmentation parameters:

[0059] The temperature of the front section of the casting rod is set to 525-555℃, and the temperature of the rear section is set to 495-525℃.

[0060] (3) Mold temperature parameters:

[0061] The die temperature is set to 470–490℃ during the initial stage of extrusion and 450–470℃ during the stable stage of extrusion.

[0062] (4) Extrusion speed segment parameters:

[0063] The extrusion speed of the extrusion section is set to 2.0–4.0 mm / s, and the extrusion speed of the extrusion front section is set to 4.0–6.0 mm / s;

[0064] (5) Extrusion outlet temperature parameters:

[0065] The extrusion outlet temperature is stabilized at 535–565℃;

[0066] (6) Staged aging process parameters: first high temperature for short time, then low temperature for long time.

[0067] The first stage of aging is carried out at a temperature of 170–200℃ for 1–4 hours, and the second stage of aging is carried out at a temperature of 140–180℃ for 3–16 hours.

[0068] The provided extrusion processing method is mainly applied to complex thin-walled aluminum alloy profiles. It significantly improves the formability, mechanical properties and production efficiency of aluminum alloy profiles, and improves the dimensional accuracy, tensile properties and fracture toughness of the profiles. It also effectively improves the extrusion efficiency, yield and stability of aluminum profiles.

[0069] The following describes the experimental verification of the extrusion processing method for complex thin-walled aluminum alloy profiles provided by this invention, using specific embodiments. Within the range of extrusion temperature, extrusion speed, and aging treatment parameters provided by this invention, multiple embodiments with combinations of these parameters were implemented. Actual production processing was conducted, and the mechanical properties of the profiles were tested to clearly demonstrate the effectiveness of the extrusion processing method provided by this invention.

[0070] Furthermore, experiments were conducted to verify the existing technology of constant extrusion temperature in the front and back sections and constant temperature aging treatment in a single time period, and the mechanical properties of the processed profiles were tested. The results were compared with the above embodiments to more clearly demonstrate the technical advantages of the method provided by the present invention over the prior art.

[0071] The following examples use commonly used 6082 aluminum profiles as the test material:

[0072] Example 1

[0073] The insulation cylinder's front section temperature is set to 450℃, and its rear section temperature to 420℃. The casting rod's front section temperature is set to 525℃, and its rear section temperature to 500℃. The die temperature during the initial extrusion stage is 480℃, and during the stable extrusion stage, the die temperature is 460℃. The extrusion speeds are 3.0 mm / s and 5.0 mm / s respectively. The extrusion outlet temperature is stabilized at 550℃. The first-stage aging temperature is 190℃, and the aging time is 2 hours. The second-stage aging temperature is 170℃, and the aging time is 8 hours.

[0074] Example 2

[0075] The insulation cylinder's front section temperature is set to 450℃, and the rear section temperature is set to 420℃. The casting rod's front section temperature is set to 540℃, and the rear section temperature is set to 515℃. The die temperature during the initial extrusion stage is 480℃, and the die temperature during the stable extrusion stage is 460℃. The extrusion speeds during the initial and final extrusion stages are 3.0 mm / s and 5.0 mm / s respectively. The extrusion outlet temperature is stabilized at 550℃. The first-stage aging temperature is 190℃, and the aging time is 2 hours. The second-stage aging temperature is 170℃, and the aging time is 8 hours.

[0076] Example 3

[0077] The insulation cylinder's front section temperature is set to 450℃, and the rear section temperature is set to 420℃. The casting rod's front section temperature is set to 550℃, and the rear section temperature is set to 525℃. The die temperature during the initial extrusion stage is 480℃, and the die temperature during the stable extrusion stage is 460℃. The extrusion speeds are 3.0 mm / s and 5.0 mm / s respectively. The extrusion outlet temperature is stabilized at 550℃. The first-stage aging temperature is 190℃, and the aging time is 2 hours. The second-stage aging temperature is 170℃, and the aging time is 8 hours.

[0078] Example 4

[0079] The insulated cylinder has a front-end temperature of 450℃ and a rear-end temperature of 420℃. The casting rod has a front-end temperature of 540℃ and a rear-end temperature of 515℃. The die temperature is 480℃ in the initial extrusion stage and 460℃ in the stable extrusion stage. The extrusion speed is 2.0 mm / s in the first stage and 4.0 mm / s in the second stage. The extrusion outlet temperature is stabilized at 550℃. The first-stage aging temperature is 190℃ for 2 hours, and the second-stage aging temperature is 170℃ for 8 hours.

[0080] Example 5

[0081] The insulated cylinder has a front-end temperature of 450℃ and a rear-end temperature of 420℃. The casting rod has a front-end temperature of 540℃ and a rear-end temperature of 515℃. The die temperature is 480℃ in the initial extrusion stage and 460℃ in the stable extrusion stage. The extrusion speed is 4.0 mm / s in the first stage and 6.0 mm / s in the second stage. The extrusion outlet temperature is stabilized at 550℃. The first-stage aging temperature is 190℃ for 2 hours, and the second-stage aging temperature is 170℃ for 8 hours.

[0082] Comparative Example 1

[0083] The insulation cylinder temperature was set at 420℃, the casting rod temperature at 530℃, the extrusion die temperature at 460℃, and the extrusion speed at 3.0 mm / s. The aging temperature was 170℃, and the aging time was 10 hours. This proportion was achieved using existing conventional technology.

[0084] Based on the experiments conducted in each embodiment, the mechanical properties of the extruded profiles were tested, and the results are summarized in Table 1.

[0085] Table 1 Performance Results Comparison Table

[0086]

[0087] Note: Mechanical property testing standard: GB / T 228 Metallic materials, tensile test at room temperature.

[0088] As can be seen from the test results in Table 1, compared with aluminum alloy sheets produced by conventional processes in the prior art, the aluminum alloy thin-walled profiles obtained using the extrusion processing method provided by this invention exhibit the following improvements: tensile strength increases from a maximum of 330 MPa to 390 MPa; yield strength increases from a maximum of 310 MPa to 370 MPa; elongation increases from a maximum of 10% to 14%; intergranular corrosion depth decreases from 161 μm to 82 μm; and flatness decreases from 0.4 mm / m to 0.1 mm / m. In other words, tensile strength increases by 20%, yield strength increases by 20%, intergranular corrosion depth decreases by 50%, and flatness improves by 75%. The above comparison demonstrates that the extrusion processing method for complex thin-walled aluminum alloy profiles of this invention significantly improves the strength, elongation, intergranular corrosion resistance, and flatness of the aluminum profiles, and also significantly increases the production efficiency of this extrusion processing method.

[0089] As can be seen from the above embodiments, the extrusion processing method for complex thin-walled aluminum alloy profiles provided by the present invention achieves high-efficiency production of aluminum profiles with high formability, high precision, high performance, high stability, and high consistency throughout the extrusion process through the coordinated matching of the temperature of the insulation cylinder, the temperature of the casting rod, the temperature of the die, and the extrusion speed. Furthermore, on-site production practice in the workshop shows that this method has technical advantages such as low cost, relatively reliable and easy-to-control process, and low equipment requirements, making it suitable for large-scale workshop production and possessing broad application prospects.

[0090] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A method for staged extrusion processing of complex thin-walled aluminum alloy profiles with segmented temperature settings, characterized in that: The extrusion press is configured with segmented settings and coordinated matching of the insulation cylinder temperature, casting rod temperature, die temperature, and extrusion speed: In the initial stage of extrusion, low-speed extrusion is configured while maintaining high temperatures in the insulation cylinder, casting rod, and die; in the later stage, high-speed extrusion is configured while maintaining low temperatures in the insulation cylinder, casting rod, and die; this achieves constant-temperature extrusion with a stable extrusion outlet temperature throughout the entire extrusion process. The extrusion method also includes a graded aging treatment of the formed complex thin-walled aluminum alloy profile, consisting of a high-temperature, short-time aging process followed by a low-temperature, long-time aging process. This graded aging treatment includes at least two stages, where the first stage aging temperature is higher than the second stage aging temperature, and the first stage aging time is shorter than the second stage aging time. And includes: The temperature parameters of the insulation cylinder are set in segments: the temperature of the front section of the insulation cylinder is set to 440~460℃, and the temperature of the rear section is set to 410~430℃. The temperature parameters for casting rods are set in segments: the temperature of the front segment of the casting rod is set to 525~555℃, and the temperature of the rear segment is set to 495~525℃. Die temperature parameters are set in segments: the die temperature is set to 470-490℃ during the initial stage of extrusion and 450-470℃ during the stable stage of extrusion. The extrusion speed parameters are set in segments: the extrusion speed in the front segment is set to 2.0–4.0 mm / s, and the extrusion speed in the rear segment is set to 4.0–6.0 mm / s. Extrusion outlet temperature parameter setting: The extrusion outlet temperature is stabilized at 535~565℃; The aging process parameters are set in stages: first, high temperature for short time, then low temperature for long time. The first stage aging temperature is set to 170-200℃, and the aging time is set to 1-4h. The second stage aging temperature is set to 140-180℃, and the aging time is set to 3-16h.

2. The method for graded extrusion processing of complex thin-walled aluminum alloy profiles with segmented temperature settings according to claim 1, characterized in that, The extrusion processing method further includes heating the die in the initial stage of extrusion and then cooling the die.

3. The method for graded extrusion processing of complex thin-walled aluminum alloy profiles with segmented temperature settings according to claim 1, characterized in that, The temperature of the insulation cylinder is set in segments, and the temperature of the insulation cylinder is set to decrease linearly along the processing direction of the extruder.

4. The method for graded extrusion processing of complex thin-walled aluminum alloy profiles with segmented temperature settings according to claim 1, characterized in that, The heating temperature of the casting rod is set in segments, and the heating temperature of the casting rod is set to decrease linearly along the processing direction of the extruder.

5. A staged extrusion processing method for complex thin-walled aluminum alloy profiles with segmented temperature settings according to claim 3 or 4, characterized in that, The extrusion speed is set in segments, and the extrusion speed is set to increase linearly along the processing direction of the extruder.

6. The method for graded extrusion processing of complex thin-walled aluminum alloy profiles with segmented temperature settings according to claim 1, characterized in that, Depending on the material of the casting rod and / or the cross-sectional shape and area of ​​the complex thin-walled aluminum alloy profile, different insulation cylinder temperatures, casting rod heating temperatures, mold temperatures, and extrusion speeds are set in stages.

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