Electromagnetic controlled quenching device and method for extruded-on-line quenching of aluminum alloy ring-shaped parts

Abstract

The application provides an electromagnetic regulation quenching device and method for extrusion-on-line quenching of an aluminum alloy ring-shaped piece, which is aimed at hollow thin-walled aluminum alloy extruded pieces, clearly defines the local micro-element eddy current action mechanism, adopts 7-16 Hz low-frequency pulse excitation, and the local micro-element eddy current can uniformly penetrate the entire thin-walled section, avoids the surface action defects caused by the high-frequency skin effect, realizes the organization homogenization, stress homogenization and thermal compensation global coverage, and adapts to the regulation and control requirements of asymmetric and open components; the first excitation coil realizes pre-extrusion temperature equalization, homogenization and stress elimination, and reduces the initial deformation from the source; the second excitation coil realizes vibration film breaking, water flow disturbance and enhanced cooling in the quenching section, breaks the steam film barrier, and improves the cooling rate and uniformity. In summary, the device and method provided by the application effectively solve the process problems of the thin-walled ring-shaped aluminum alloy piece, such as residual stress concentration after extrusion, large circumferential temperature difference, steam film barrier cooling in the quenching section and the like.

Description

Technical Field

[0001] This invention belongs to the field of aluminum alloy extrusion processing and online heat treatment technology, and particularly relates to an electromagnetically controlled quenching device and method for extruding and quenching aluminum alloy ring parts online. Background Technology

[0002] Hollow thin-walled aluminum alloy extrusions, with their advantages of lightweight, high specific strength, and corrosion resistance, are widely used in core fields such as aerospace, defense, rail transportation, and new energy vehicles. Currently, the mainstream manufacturing process adopts an integrated extrusion molding-online quenching process. However, this process faces many insurmountable technical challenges in actual production.

[0003] Firstly, after the hollow thin-walled aluminum alloy extrusion parts are extruded, the heat dissipation rate of each part is significantly different, the temperature gradient of the workpiece in the circumferential direction and the inner and outer walls is large, and the residual stress of extrusion is unevenly distributed, which can easily cause initial warping and deformation.

[0004] Secondly, for hollow thin-walled aluminum alloy extrusions, there is generally a certain distance from the extruder outlet to the quenching equipment inlet. During this process, the hollow thin-walled extrusions achieve high-temperature solid solution during extrusion, resulting in high outlet temperature. The distribution in the air can easily cause coarse recrystallization grains and uneven structure in the core.

[0005] Third, when high-temperature hollow thin-walled aluminum alloy extrusions enter the spray quenching section, their surfaces vaporize instantly upon contact with cooling water, forming a dense vapor film and attached bubbles. The vapor has an extremely low thermal conductivity, which prevents the cooling water from effectively contacting the workpiece substrate, resulting in insufficient cooling rate and uneven circumferential cooling. This further exacerbates the deformation of the extrusions and fails to meet the requirements of the solution quenching process.

[0006] Fourth, aluminum alloy extrusions in the quenching section are greatly affected by the quenching process, making them prone to warping and deformation, scratching and interference with the quenching equipment, dense arrangement of cooling media such as spray water and gas and pipelines, small space for quenching equipment, and vibration, which have a great impact on the extrusion forming quality. It is also difficult to control the steam film and attached bubbles during the quenching process.

[0007] The aforementioned difficulties have become technical problems limiting the quality improvement of the integrated extrusion molding-online quenching process and the extrusion manufacturing process of aluminum alloy ring parts of different systems. Summary of the Invention

[0008] To address the shortcomings and deficiencies of existing technologies, an electromagnetically controlled quenching device and method for extrusion-online quenching of aluminum alloy ring parts are provided. This method can solve process problems such as residual stress concentration, large circumferential temperature difference, and steam film blockage cooling in the quenching section after extrusion of hollow thin-walled aluminum alloy extrusion parts.

[0009] The present invention provides an electromagnetically controlled quenching device and method for extrusion-online quenching of aluminum alloy ring parts, comprising an electromagnetic control mechanism and an electromagnetic strengthening mechanism. The electromagnetic control mechanism is located between the discharge end of the extruder and the spray quenching zone, and the electromagnetic strengthening mechanism is located within the spray quenching zone. The extruded part passes through the inner cavities of the electromagnetic control mechanism and the electromagnetic strengthening mechanism and moves along the workpiece extrusion conveying direction. A certain air isolation gap is reserved between the inner cavities of the electromagnetic control mechanism and the electromagnetic strengthening mechanism and the extruded part. n sets of water nozzles are provided in front of the electromagnetic strengthening mechanism. After being energized, the electromagnetic control mechanism generates an axial alternating magnetic field, the direction of which is perpendicular to the workpiece extrusion conveying direction. The magnetic field lines are radially penetrating the thin-walled section, inducing local micro-element eddy currents in the continuous region of the conductor, thus achieving pre-electromagnetic control. After the electromagnetic strengthening structure is energized, it generates a radial alternating magnetic field, which penetrates the thin-walled section laterally. Without interfering with the spray cooling, it quickly punctures the steam film and attached bubbles, increasing the contact area with the extruded part, thereby achieving electromagnetic strengthening cooling. The electromagnetic control mechanism and the electromagnetic strengthening mechanism are respectively connected to the corresponding power supply unit. The power supply unit emits a low-frequency alternating rectangular pulse current to generate a stable axial alternating magnetic field and a radial alternating magnetic field, which work together to complete the electromagnetic control and quenching strengthening cooling. Where n=1, 2, 3...

[0010] As a further improvement to the above solution, the electromagnetic control mechanism includes a first radial pure aluminum shielding cylinder, both ends of which are fixed with a first pure aluminum end panel. A first radial silicon steel shielding cover is fitted inside the first radial pure aluminum shielding cylinder. A first insulating gasket is provided between the inner wall of the first radial pure aluminum shielding cylinder and the outer wall of the first radial silicon steel shielding cover. Both ends of the first radial silicon steel shielding cover are fixed with a first silicon steel annular plate. A first excitation coil is provided inside the first radial silicon steel shielding cover. The first excitation coil adopts a coaxial cylindrical solenoid structure. The outer wall of the spiral tube of the first excitation coil is fitted with a water-cooled heat insulation sleeve. Both the first pure aluminum end panel and the first silicon steel annular plate have a central opening structure.

[0011] As a further improvement to the above scheme, the electromagnetic strengthening structure includes a second radial pure aluminum shielding cylinder, with a second pure aluminum end panel fixed at both ends of the second radial pure aluminum shielding cylinder. A second radial silicon steel shielding cover is fitted inside the second radial pure aluminum shielding cylinder. A second insulating gasket is provided between the inner wall of the second radial pure aluminum shielding cylinder and the outer wall of the second radial silicon steel shielding cover. A second silicon steel annular plate is fixed at both ends of the second radial silicon steel shielding cover. A second excitation coil is provided inside the second radial silicon steel shielding cover. The second excitation coil adopts four sets of annular coils arranged axially. The four sets of annular coils are arranged at 90° intervals along the outer surface of the extruder, with the saddle-shaped annular surface of the annular coil parallel to the conveying axis of the extruder and having a gap with the outer surface of the extruder. A water-cooled heat insulation sleeve is provided on the outer surface of the annular coil. Both the second pure aluminum end panel and the second silicon steel annular plate have a central opening structure, and the inner hole of the second pure aluminum end panel is larger than the inner hole of the first silicon steel annular plate.

[0012] As a further improvement to the above scheme, the first excitation coil and the outer surface of the extrusion part are reserved with an air isolation gap of 80-120mm, the axial length is 300-450mm, and it is made of high temperature resistant glass fiber wrapped flat copper wire with a single layer of unidirectional dense winding, 34-42 turns, and the conductor cross-section specification is 14-18mm².

[0013] As a further improvement to the above scheme, an air isolation gap of 80-120mm is reserved between the second excitation coil and the outer surface of the extrusion piece, the axial length of a single ring coil is 150-200mm, the number of turns is 28-38, and the conductor cross-section is 12-16mm².

[0014] As a further improvement to the above scheme, the thickness of the first radial pure aluminum shielding cylinder and the second radial pure aluminum shielding cylinder is 10-20mm; the first radial silicon steel shielding cover and the second radial silicon steel shielding cover are both made of silicon steel sheets and have a total thickness of 0.35-0.5mm, with a magnetic permeability ≥10000.

[0015] As a further improvement to the above solution, a temperature control linkage unit is also included. The temperature control linkage unit includes a multi-point non-contact infrared thermometer and a PLC control cabinet. The multi-point non-contact infrared thermometers are all connected to the PLC control cabinet. The infrared thermometers cover the circumferential, major and minor axes, thin-walled and thick-ribbed parts of the extruded part, and collect temperature signals at each point in real time and transmit them to the PLC control cabinet. The PLC control cabinet is linked with the extruder, power supply unit, water pump and flow regulating valve in the spray quenching zone. Based on the real-time temperature gradient and workpiece deformation, it adjusts the excitation current, frequency and spray water pressure and flow rate in a closed loop to achieve precise control throughout the entire process.

[0016] A method for using an electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts includes the following steps:

[0017] S1. Extrusion molding: After heating the aluminum alloy ingot, it is extruded by an extruder to obtain a thin-walled extruded part with a wall thickness of 3-15mm. The extrusion discharge temperature is controlled to be no lower than the minimum solution temperature. The extruded part moves forward continuously, passes through the electromagnetic control mechanism, and then the traction machine pulls the aluminum profile.

[0018] S2. Electromagnetic control of the electromagnetic control mechanism: When the extruded part enters the inner cavity of the electromagnetic control mechanism, the power supply unit provides low-frequency pulse current to the electromagnetic control mechanism to generate an axial alternating magnetic field, forming local micro-element eddy currents inside the extruded part to complete the temperature uniformity, homogenization, stress relief and pre-conditioning.

[0019] S3. Electromagnetic strengthening quenching of electromagnetic strengthening structure: The extruded part enters the spray quenching zone. Water mist is sprayed from the nozzles in the spray quenching zone and enters the inner cavity of the electromagnetic strengthening structure. The power supply unit supplies low-frequency pulse current to the electromagnetic strengthening structure, generating a radial alternating magnetic field inside the extruded part. This rapidly pierces the steam film and attached bubbles, increasing the contact area with the extruded part to achieve enhanced cooling.

[0020] S4. Shaping and Aging: After quenching, the extruded parts are pulled, rounded, sawed, and aged to obtain the finished product.

[0021] As a further improvement to the above solution, the operating parameters of the power supply unit are: frequency 7-16Hz, current 220-380A, excitation voltage ≤60V, pulse duty cycle 30%-50%, corresponding to an electromagnetic skin depth of 38-58mm for high-temperature aluminum alloys, and suitable for extruded parts with a wall thickness of 3-15mm.

[0022] As a further improvement to the above scheme, when the electromagnetic control mechanism and electromagnetic reinforcement structure are working, the alternating electromagnetic volume force density generated inside the extruder ranges from 11 to 215 kN / m³.

[0023] The beneficial effects of this invention are:

[0024] Compared with the prior art, the electromagnetically controlled quenching device and method for extrusion-online quenching of aluminum alloy ring parts provided by the present invention has the following advantages:

[0025] 1. Suitable for hollow, thin-walled aluminum alloy extrusions, with a rational magnetic field layout.

[0026] For hollow thin-walled aluminum alloy extrusions, the mechanism of local micro-element eddy current action is clarified. The coaxial ring coil in the electromagnetic control mechanism covers the entire cross-section of the extrusion forming zone, realizing efficient electromagnetic control. The four sets of circumferentially distributed saddle-shaped coils in the electromagnetic strengthening mechanism completely solve the problems of deformation interference and spray obstruction. The dual-coil layout is suitable for various irregular thin-walled extrusions.

[0027] 2. Full-range vortex penetration ensures uniform and thorough control.

[0028] Employing 7-16Hz low-frequency pulse excitation, the electromagnetic skin depth is much greater than the wall thickness of the extruded part under high-temperature conditions. Local micro-element eddy currents can uniformly penetrate the entire thin-walled section, avoiding surface defects caused by high-frequency skin effect, achieving full coverage of homogeneous structure, stress homogenization, and thermal compensation, and adapting to the control requirements of asymmetric and open components.

[0029] 3. Dual-function synergy solves the core pain points of quenching.

[0030] The first excitation coil achieves pre-extrusion temperature equalization, homogenization, and stress relief, reducing initial deformation from the source; the second excitation coil achieves vibration-induced membrane breaking and water flow disturbance-enhanced cooling in the quenching section, breaking through the steam film barrier and improving the cooling rate and uniformity.

[0031] 4. Double-layer composite shielding eliminates potential equipment safety hazards.

[0032] The silicon steel shielding cover and pure aluminum shielding cylinder form a double-layer composite shielding structure. Combined with an 80-120mm air isolation gap, it forms a triple shielding system of "magnetic concentration-demagnetization-isolation". This effectively gathers and cancels the low-frequency alternating magnetic field, completely preventing magnetic field leakage from causing induction heating and magnetization failure of surrounding steel components, and ensuring the safe operation of the equipment.

[0033] In summary, the device and method provided by this invention effectively solve the process problems such as residual stress concentration, large circumferential temperature difference, and steam film blockage cooling in the quenching section after extrusion of hollow thin-walled aluminum alloy extrusion parts. Attached Figure Description

[0034] Figure 1 This is a schematic diagram of the electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts in this invention;

[0035] Figure 2 This is a cross-sectional schematic diagram of the electromagnetic control mechanism in this invention;

[0036] Figure 3 This is a schematic diagram of the first excitation coil in this invention;

[0037] Figure 4 This is a cross-sectional schematic diagram of the electromagnetic strengthening mechanism in this invention;

[0038] Figure 5 This is a schematic diagram of the second excitation coil in this invention;

[0039] Figure 6 This is a cross-sectional schematic diagram of the annular coil in this invention;

[0040] Figure 7 This is a flowchart of the operation of the temperature control linkage unit in this invention.

[0041] Wherein: 1-Extrusion press; 2-Electromagnetic control mechanism; 3-Water nozzle; 4-Extruded part; 5-Electromagnetic strengthening mechanism; 201-First pure aluminum end panel; 202-First radial pure aluminum shielding cylinder; 203-First insulating gasket; 204-First radial silicon steel shielding cover; 205-First excitation coil; 206-First silicon steel annular sheet; 207-Water-cooled heat insulation sleeve; 501-Second pure aluminum end panel; 502-Second radial pure aluminum shielding cylinder; 503-Second insulating gasket; 504-Second radial silicon steel shielding cover; 505-Second silicon steel annular sheet; 506-Second excitation coil; 507-Annular coil. Detailed Implementation

[0042] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings:

[0043] according to Figure 1 As shown, this invention provides an electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts. It includes an electromagnetic control mechanism 2 and an electromagnetic strengthening mechanism 5. The electromagnetic control mechanism 2 is located between the discharge end of the extruder 1 and the spray quenching area, while the electromagnetic strengthening mechanism 5 is located within the spray quenching area. The extruded part 4 from the extruder 1 passes through the inner cavities of the electromagnetic control mechanism 2 and the electromagnetic strengthening mechanism 5 and moves along the workpiece extrusion conveying direction. A certain air isolation gap is reserved between the inner cavities of the electromagnetic control mechanism 2 and the electromagnetic strengthening mechanism 5 and the extruded part 4. n sets of water nozzles 3 are provided in front of the electromagnetic strengthening mechanism 5. After being energized, the electromagnetic control mechanism 2 generates an axial alternating magnetic field, the direction of which is perpendicular to the workpiece extrusion conveying direction. The magnetic field lines are directed in the same direction, radially penetrating the thin-walled section and inducing local micro-element eddy currents in the continuous region of the conductor, thus achieving pre-electromagnetic control. After being energized, the electromagnetic strengthening structure 5 generates a radial alternating magnetic field, which transversely penetrates the thin-walled section. Without interfering with spray cooling, it rapidly punctures the steam film and attached bubbles, increasing the contact area with the extruded part 4, thereby achieving electromagnetic strengthening cooling. The electromagnetic control mechanism 2 and the electromagnetic strengthening mechanism 5 are respectively connected to their corresponding power supply units. The power supply units emit low-frequency alternating positive and negative rectangular pulse currents to generate stable axial and radial alternating magnetic fields, collaboratively completing electromagnetic control and quenching strengthening cooling; where n = 1, 2, 3… Where:

[0044] ①According to Figures 2-3As shown, the electromagnetic control mechanism 2 includes a first radial pure aluminum shielding cylinder 202. Both ends of the first radial pure aluminum shielding cylinder 202 are fixed with first pure aluminum end panels 201. A first radial silicon steel shielding cover 204 is fitted inside the first radial pure aluminum shielding cylinder 202. A first insulating gasket 203 is provided between the inner wall of the first radial pure aluminum shielding cylinder 202 and the outer wall of the first radial silicon steel shielding cover 204. Both ends of the first radial silicon steel shielding cover 204 are fixed with first silicon steel annular plates 206. A first... The first excitation coil 205 adopts a coaxial cylindrical solenoid structure. The outer wall of the spiral tube of the first excitation coil 205 is covered with a water-cooled heat insulation sleeve 207. The first pure aluminum end panel 201 and the first silicon steel annular plate 206 are both centrally opened structures. An air isolation gap of 80-120mm is reserved between the first excitation coil 205 and the outer surface of the extrusion part 4. The axial length is 300-450mm. It is made of high-temperature resistant glass fiber wrapped flat copper wire with a single layer of unidirectional dense winding, 34-42 turns, and the conductor cross-section specification is 14-18mm².

[0045] ②According to Figures 4-5 As shown, the electromagnetic strengthening structure 5 includes a second radial pure aluminum shielding cylinder 502. Both ends of the second radial pure aluminum shielding cylinder 502 are fixed with second pure aluminum end panels 501. A second radial silicon steel shielding cover 504 is fitted inside the second radial pure aluminum shielding cylinder 502. A second insulating gasket 503 is provided between the inner wall of the second radial pure aluminum shielding cylinder 502 and the outer wall of the second radial silicon steel shielding cover 504. Both ends of the second radial silicon steel shielding cover 504 are fixed with second silicon steel annular plates 505. A second excitation coil 506 is arranged inside the second radial silicon steel shielding cover 504. The second excitation coil 506 adopts four sets of annular coils 507 arranged axially. The ring coil 507 is arranged at 90° intervals along the outer surface of the extruder 4, with its saddle-shaped ring surface parallel to the conveying axis of the extruder 4 and with a gap from the outer surface of the extruder 4. The outer surface of the ring coil 507 is provided with a water-cooled heat insulation sleeve 207. The second pure aluminum end panel 501 and the second silicon steel ring plate 505 are both centrally opened structures, and the inner hole of the second pure aluminum end panel 501 is larger than the inner hole of the first silicon steel ring plate 206. The second excitation coil 506 and the outer surface of the extruder 4 are reserved with an air isolation gap of 80-120mm. The axial length of a single ring coil 507 is 150-200mm, the number of turns is 28-38, and the conductor cross-section is 12-16mm².

[0046] In addition, the thickness of the first radial pure aluminum shielding cylinder 202 and the second radial pure aluminum shielding cylinder 502 is 10-20mm; the first radial silicon steel shielding cover 204 and the second radial silicon steel shielding cover 504 are both made of silicon steel sheets and have a total thickness of 0.35-0.5mm, with a magnetic permeability ≥10000.

[0047] ③According to Figure 6 As shown, the device also includes a temperature control linkage unit, which includes a multi-point non-contact infrared thermometer and a PLC control cabinet. The multi-point non-contact infrared thermometers are all connected to the PLC control cabinet. The infrared thermometers cover the circumference, major and minor axes, thin walls and thick ribs of the extruded part 4, and collect temperature signals at each point in real time and transmit them to the PLC control cabinet. The PLC control cabinet is linked with the extruder 6, the power supply unit, the water pump and flow regulating valve in the spray quenching zone, and adjusts the excitation current, frequency and spray water pressure and flow rate in a closed loop according to the real-time temperature gradient and workpiece deformation to achieve precise control of the entire process.

[0048] A method for using an electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts includes the following steps:

[0049] S1. Extrusion molding: After heating the aluminum alloy ingot, it is extruded by the extruder 1 to obtain a thin-walled extruded part 4 with a wall thickness of 3-15mm. The extrusion discharge temperature is controlled not to be lower than the minimum solution temperature. The extruded part 4 moves forward continuously, passes through the electromagnetic control mechanism 2, and then the traction machine pulls the aluminum profile.

[0050] S2. Electromagnetic control of electromagnetic control mechanism 2: The extruded part 4 enters the inner cavity of electromagnetic control mechanism 2. The power supply unit provides low-frequency pulse current to electromagnetic control mechanism 2 to generate an axial alternating magnetic field, forming local micro-element eddy current inside the extruded part 4 to complete the temperature uniformity, homogenization, stress relief and pre-conditioning.

[0051] S3. Electromagnetic strengthening quenching of electromagnetic strengthening structure 5: The extruded part 4 enters the spray quenching zone. The water nozzle 3 in the spray quenching zone sprays water mist and enters the inner cavity of the electromagnetic strengthening structure 5 at the same time. The power supply unit sends a low-frequency pulse current to the electromagnetic strengthening structure 5, which generates a radial alternating magnetic field inside the extruded part 4, quickly piercing the steam film and attached bubbles to increase the contact area with the extruded part 4 and achieve strengthening cooling.

[0052] S4. Shaping and Aging: After quenching, the extruded part is pulled, rounded, sawed, and aged to obtain the finished product.

[0053] During the above operation, the operating parameters of the power supply unit are frequency 7-16Hz, current 220-380A, excitation voltage ≤60V, pulse duty cycle 30%-50%, corresponding to an electromagnetic skin depth of 38-58mm for high-temperature aluminum alloys, and suitable for extruded parts 4 with a wall thickness of 3-15mm; when the electromagnetic control mechanism 2 and the electromagnetic reinforcement structure 5 are working, the alternating electromagnetic volume force density generated inside the extruded part 4 ranges from 11 to 215kN / m³.

[0054] Example 1

[0055] This embodiment focuses on a 5mm thick 6005A upper-opening trapezoidal thin-walled aluminum alloy part, processed using an electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts. Specific parameters are as follows:

[0056] 1. Extrusion molding: The 6005A aluminum alloy ingot is heated to 475℃ and extruded to obtain extruded part 4, which is an open trapezoidal thin-walled part with a wall thickness of 5mm. The extrusion discharge temperature is 530℃, which is higher than the minimum solution temperature of 525℃ of the alloy. The conveying speed is 8m / min.

[0057] 2. Parameters of the first excitation coil 205 in the electromagnetic control mechanism 2: It adopts a coaxial cylindrical solenoid coil, with a gap of 15mm between it and the outer surface of the extrusion part 4, an axial length of 380mm, 38 turns, and a conductor cross-section of 16mm².

[0058] 3. Power supply unit parameters: excitation voltage 50V, operating frequency 7Hz, operating current 220A, pulse duty cycle 30%;

[0059] 4. Other parameters of the electromagnetic control mechanism 2 and electromagnetic reinforcement structure 5: The first radial silicon steel shield 204 and the second radial silicon steel shield 504 are both made of stacked silicon steel sheets and have a total thickness of 0.35mm. The thickness of the first radial pure aluminum shield cylinder 202 and the second radial pure aluminum shield cylinder 502 is 15mm. The air isolation gap is 100mm.

[0060] 5. Quenching process: Spray cooling rate of 350℃ / min, followed by T5 aging treatment.

[0061] This embodiment calculates the electromagnetic skin depth and electromagnetic volume force.

[0062] 1. Electromagnetic skin depth calculation

[0063] High temperature aluminum alloy resistivity Vacuum permeability angular frequency Electromagnetic skin depth formula:

[0064] ;

[0065] Substitute parameters: Calculated It has a workpiece wall thickness of much greater than 5mm, and the eddy current penetrates the entire domain.

[0066] 2. Calculation of Electromagnetic Volume Force

[0067] The fundamental source of the volume force in electromagnetic stirring is the Lorentz force. The formula for the volume force density under an alternating magnetic field is as follows:

[0068] ;

[0069] In the formula: This is the operating current. This refers to the pulse duty cycle.

[0070] Substitute parameters for calculation: , Calculated

[0071] .

[0072] Example 2

[0073] This embodiment focuses on the processing of a 12mm thick, round, thin-walled aluminum alloy part of type 6005A using an electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts. Specific parameters are as follows:

[0074] 1. Extrusion molding: The 6005A aluminum alloy ingot is heated to 485℃ and extruded to obtain extruded part 4, which is a round part with a wall thickness of 12mm. The extrusion discharge temperature is 535℃ and the conveying speed is 12m / min.

[0075] 2. Parameters of the second excitation coil 506 in the electromagnetic reinforcement structure 5: Four sets of ring coils 507 are arranged axially, each set of ring coils 507 has an axial length of 320mm, 32 turns, and a conductor cross-section of 14mm².

[0076] 3. Power supply unit parameters: excitation voltage 55V, operating frequency 16Hz, operating current 380A, pulse duty cycle 50%;

[0077] 4. Other parameters of the electromagnetic control mechanism 2 and electromagnetic reinforcement structure 5: The first radial silicon steel shield 204 and the second radial silicon steel shield 504 are both made of stacked silicon steel sheets and have a total thickness of 0.5mm. The thickness of the first radial pure aluminum shield cylinder 202 and the second radial pure aluminum shield cylinder 502 is 18mm. The air isolation gap is 110mm.

[0078] 5. Quenching process: Spray cooling rate 420℃ / min, followed by T6 aging treatment.

[0079] This embodiment calculates the electromagnetic skin depth and electromagnetic volume force.

[0080] 1. Electromagnetic skin depth calculation

[0081] Substitution The skin depth formula yields: For workpieces with a wall thickness greater than 12mm, eddy currents uniformly penetrate the cross-section.

[0082] 2. Calculation of Electromagnetic Volume Force

[0083] Substituting into the volumetric density formula:

[0084] ;

[0085] Example 3

[0086] This embodiment is for a 6005A asymmetric elliptical thin-walled aluminum alloy part with a wall thickness of 10mm. It is processed with median parameters, excitation voltage of 52V, working frequency of 12Hz, working current of 300A, and duty cycle of 40%. The other structural parameters are the same as those in embodiments 1 and 2. The calculated electromagnetic skin depth is ≈44.2mm and the electromagnetic volume force density is ≈86.37kN / m³.

[0087] Testing revealed that the aluminum alloy components processed according to the various embodiments of the present invention exhibited an extrusion residual stress relief rate of ≥65%, no steam film adhesion during quenching, a workpiece deformation rate of ≤1.2%, no induced heating or magnetization phenomena in the surrounding steel equipment, and sufficient solid solution of the 6005A aluminum alloy reinforcing phase, with mechanical properties meeting the requirements for aerospace-grade use.

[0088] The above embodiments are not limited to the technical solutions of the embodiments themselves, and the embodiments can be combined with each other to form new embodiments. The above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of the technical solutions of the present invention.

Claims

1. An electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts, characterized in that: It includes an electromagnetic control mechanism (2) and an electromagnetic strengthening mechanism (5). The electromagnetic control mechanism (2) is located between the discharge end of the extruder (1) and the spray quenching area. The electromagnetic strengthening mechanism (5) is located within the spray quenching area. The extruded part (4) from the extruder (1) passes through the inner cavity of the electromagnetic control mechanism (2) and the electromagnetic strengthening mechanism (5) and moves along the workpiece extrusion and conveying direction. A certain air isolation gap is reserved between the inner cavity of the electromagnetic control mechanism (2) and the electromagnetic strengthening mechanism (5) and the extruded part (4). n sets of water nozzles (3) are provided in front of the electromagnetic strengthening mechanism (5). After the electromagnetic control mechanism (2) is energized, it generates an axial alternating magnetic field. The direction of the magnetic field is the same as the workpiece extrusion and conveying direction. The magnetic field lines penetrate the thin-walled section radially, inducing local micro-element eddy currents in the continuous region of the conductor, thereby realizing pre-electromagnetic control; the electromagnetic strengthening structure (5) generates a radial alternating magnetic field after being energized. The magnetic field penetrates the thin-walled section laterally, and without interfering with the spray cooling, it quickly punctures the steam film and attached bubbles to increase the contact area with the extruded part (4), thereby realizing electromagnetic strengthening cooling; the electromagnetic control mechanism (2) and the electromagnetic strengthening mechanism (5) are respectively connected to the corresponding power supply unit. The power supply unit emits a low-frequency positive and negative alternating rectangular pulse current to generate a stable axial alternating magnetic field and a radial alternating magnetic field, which work together to complete the electromagnetic control and quenching strengthening cooling; where n=1, 2, 3...

2. The electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts according to claim 1, characterized in that: The electromagnetic control mechanism (2) includes a first radial pure aluminum shielding cylinder (202), with first pure aluminum end panels (201) fixed at both ends of the first radial pure aluminum shielding cylinder (202). A first radial silicon steel shielding cover (204) is fitted inside the first radial pure aluminum shielding cylinder (202). A first insulating gasket (203) is provided between the inner wall of the first radial pure aluminum shielding cylinder (202) and the outer wall of the first radial silicon steel shielding cover (204). Both ends are fixed with a first silicon steel annular plate (206), and the first radial silicon steel shield (204) is provided with a first excitation coil (205). The first excitation coil (205) is electrically connected to the power supply unit. The first excitation coil (205) adopts a coaxial cylindrical solenoid structure. The outer wall of the spiral tube of the first excitation coil (205) is covered with a water-cooled heat insulation sleeve (207). The first pure aluminum end panel (201) and the first silicon steel annular plate (206) are both centrally opened structures.

3. The electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts according to claim 2, characterized in that: The electromagnetic strengthening structure (5) includes a second radial pure aluminum shielding cylinder (502), with second pure aluminum end panels (501) fixed at both ends of the second radial pure aluminum shielding cylinder (502). A second radial silicon steel shielding cover (504) is fitted inside the second radial pure aluminum shielding cylinder (502). A second insulating gasket (503) is provided between the inner wall of the second radial pure aluminum shielding cylinder (502) and the outer wall of the second radial silicon steel shielding cover (504). A second silicon steel annular plate (505) is fixed at both ends of the second radial silicon steel shielding cover (504). A second excitation coil (506) is provided inside the second radial silicon steel shielding cover (504). The magnetic coil (506) is electrically connected to the power supply unit. The second excitation coil (506) adopts four sets of ring coils (507) arranged axially. The four sets of ring coils (507) are arranged at 90° intervals along the outer surface of the extruder (4) from top to bottom, left to right. The saddle-shaped ring surface of the ring coil (507) is parallel to the conveying axis of the extruder (4) and has a gap with the outer surface of the extruder (4). The outer surface of the ring coil (507) is provided with a water-cooled heat insulation sleeve (207). The second pure aluminum end panel (501) and the second silicon steel ring plate (505) are both centrally opened structures, and the inner hole of the second pure aluminum end panel (501) is larger than the inner hole of the first silicon steel ring plate (206).

4. The electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts according to claim 3, characterized in that: The first excitation coil (205) and the outer surface of the extrusion piece (4) have an air isolation gap of 80-120mm, an axial length of 300-450mm, and are made of high temperature resistant glass wire wrapped flat copper wire in a single layer in the same direction with 34-42 turns and a conductor cross-section of 14-18mm².

5. The electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts according to claim 4, characterized in that: The second excitation coil (506) and the outer surface of the extrusion piece (4) have an air isolation gap of 80-120mm. The axial length of the single ring coil (507) is 150-200mm, the number of turns is 28-38, and the conductor cross-section is 12-16mm².

6. The electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts according to claim 5, characterized in that: The thickness of the first radial pure aluminum shielding cylinder (202) and the second radial pure aluminum shielding cylinder (502) is 10-20mm; the first radial silicon steel shielding cover (204) and the second radial silicon steel shielding cover (504) are both made of stacked silicon steel sheets and have a total thickness of 0.35-0.5mm, with a magnetic permeability ≥10000.

7. The electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts according to claim 6, characterized in that: It also includes a temperature control linkage unit, which includes a multi-point non-contact infrared thermometer and a PLC control cabinet. The multi-point non-contact infrared thermometer is connected to the PLC control cabinet. The infrared thermometer covers the circumferential, long and short axis, thin wall and thick rib parts of the extruded part (4), and collects the temperature signal of each point in real time and transmits it to the PLC control cabinet. The PLC control cabinet is linked with the extruder (6), power supply unit, water pump and flow regulating valve in the spray quenching zone. According to the real-time temperature gradient and workpiece deformation, it adjusts the excitation current, frequency and spray water pressure and flow in a closed loop to achieve precise control of the whole process.

8. A method of using an electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts as described in claim 7, characterized in that, Includes the following steps: S1. Extrusion molding: After heating the aluminum alloy ingot, it is extruded by the extruder (1) to obtain a thin-walled extruded part (4) with a wall thickness of 3-15mm. The extrusion discharge temperature is controlled to be no lower than the minimum solid solution temperature. The extruded part (4) moves forward continuously, passes through the electromagnetic control mechanism (2), and then the traction machine pulls the aluminum profile. S2. Electromagnetic control of electromagnetic control mechanism (2): The extrusion part (4) enters the inner cavity of the electromagnetic control mechanism (2), and the power supply unit provides low-frequency pulse current to the electromagnetic control mechanism (2) to generate an axial alternating magnetic field, forming a local micro-element eddy current inside the extrusion part (4) to complete the temperature equalization, homogenization, stress relief and pre-conditioning. S3. Electromagnetic strengthening quenching of electromagnetic strengthening structure (5): The extruded part (4) enters the spray quenching zone. The water nozzle (3) in the spray quenching zone sprays water mist and enters the inner cavity of the electromagnetic strengthening structure (5). The power supply unit supplies low-frequency pulse current to the electromagnetic strengthening structure (5) to generate a radial alternating magnetic field inside the extruded part (4), which quickly pierces the steam film and attached bubbles to increase the contact area with the extruded part (4) to achieve enhanced cooling. S4. Shaping and aging: After quenching, the extruded parts (4) are pulled, rounded, sawed, and aged to obtain the finished product.

9. The method of using the electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts according to claim 8, characterized in that: The operating parameters of the power supply unit are frequency 7-16Hz, current 220-380A, excitation voltage ≤60V, pulse duty cycle 30%-50%, corresponding to an electromagnetic skin depth of 38-58mm for high-temperature aluminum alloys, and suitable for extruded parts with a wall thickness of 3-15mm (4).

10. The method of using the electromagnetically controlled quenching device for extrusion-online quenching of aluminum alloy ring parts according to claim 9, characterized in that: When the electromagnetic control mechanism (2) and the electromagnetic reinforcement structure (5) are working, the alternating electromagnetic volume force density generated inside the extruder (4) ranges from 11 to 215 kN / m³.

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