Electromagnetic indirect rapid heating device and method for thin-walled component of titanium alloy material

Abstract

The application relates to a kind of electromagnetic indirect rapid heating device and method of titanium alloy material thin-walled component, and belongs to the field of material heating device.The existing electromagnetic induction heating mode cannot realize the direct and rapid heating of titanium alloy material plate component.The electromagnetic indirect rapid heating device and method of titanium alloy material thin-walled component comprises the following steps: spraying boron nitride spray on the surface of plate blank;radiation heating block is heated by electromagnetic induction and maintained at a constant temperature;start chain motor, and place plate blank at the initial position on the chain outside the radiation heating block during the motor intermittent time;send plate blank into the radiation heating block during the motor conveying stage;heat plate blank in the radiation heating block within the heating range during the next electrode intermittent time;send plate blank out of the radiation heating block during the motor conveying stage.The application can accurately and rapidly realize the purpose of rapidly heating titanium alloy material plate component by electromagnetic induction.

Description

Technical Field

[0001] This invention relates to a heating device and method for thin-walled components, and particularly to an electromagnetic indirect rapid heating device and method for thin-walled components made of titanium alloy. Background Technology

[0002] Titanium alloys, as a new type of lightweight and high-strength material, possess characteristics such as high strength, high toughness, corrosion resistance, excellent fatigue performance, excellent high-temperature mechanical properties, and high strength-to-weight ratio, and are widely used in the aerospace and defense fields. However, due to the high yield strength, low Young's modulus, and low room temperature elongation of titanium alloys, they are prone to cracking during plastic processing, and the formed components exhibit significant springback, making them extremely difficult to form.

[0003] Existing methods for forming thin-walled titanium alloy components mostly employ isothermal forming processes. This process requires heating the mold to the forming temperature. Since the mold's mass is much greater than that of the formed component, isothermal forming incurs significant heat consumption, mold costs, and time costs. To address this issue, the inventors proposed a novel non-equilibrium hot stamping process for titanium alloys. This process rapidly heats the material to form a non-equilibrium microstructure, ensuring the formability of the sheet metal during the hot stamping process and enabling the production application of titanium alloy hot stamping technology.

[0004] Existing rapid heating methods mostly employ electromagnetic induction heating, which is divided into two types: magnetic field parallel to the plate and magnetic field perpendicular to the plate. While a magnetic field perpendicular to the plate can achieve a high heating rate, the skin effect of electromagnetic induction makes it difficult to achieve the required temperature uniformity for hot stamping processes when rapidly heating thin-walled titanium alloy plates. When a magnetic field parallel to the plate acts on the titanium alloy plate, the plate thickness and the magnetic permeability of the titanium alloy limit the generation of strong eddy currents within the plate, thus failing to achieve the required heating rate. Increasing the power can improve the heating rate, but due to the low efficiency of electromagnetic induction heating, the increased heating rate will result in significant Joule heating, which will substantially increase the cost of the electromagnetic induction power supply and water-cooling pipes, thus restricting the application of electromagnetic heating in thin-walled titanium alloy plates.

[0005] To address the challenge of achieving rapid heating via electromagnetic induction heating, this application proposes a method and device for indirect rapid electromagnetic heating of thin-walled titanium alloy plates. This method utilizes electromagnetic induction to heat an annular radiant heating block that is prone to eddy current effects, and then uses the high-temperature heating block to achieve radiant heating of the titanium alloy plate, thus realizing indirect rapid electromagnetic induction heating of thin-walled titanium alloy plates. Summary of the Invention

[0006] The purpose of this invention is to solve the problem that existing electromagnetic induction heating methods cannot achieve direct and rapid heating of titanium alloy sheet components, and to propose an electromagnetic indirect rapid heating device and method for thin-walled titanium alloy components.

[0007] The above objectives are achieved through the following technical solutions:

[0008] An electromagnetic indirect rapid heating device for thin-walled titanium alloy components comprises a heating system, a conveying device, a high-frequency induction power supply, a heating device support, and a set of temperature sensors.

[0009] The heating device bracket is the supporting part of the entire equipment;

[0010] The high-frequency induction power supply is located at the bottom of the heating device bracket;

[0011] The heating system is positioned above the high-frequency induction power supply, and the interior of the heating system is hollow.

[0012] The conveying device is used to carry the sheet metal blank. The middle part of the conveying device is located inside the heating system, and both ends of the conveying device are located outside the heating system, with both ends mounted on the heating device support. Temperature sensors are installed on the heating system.

[0013] The heating system includes a radiant heating block, an insulation layer, and an electromagnetic induction coil;

[0014] The radiant heating block has a keyway-shaped cross-section and is a hollow block. The hollow part is used to accommodate the conveying device and the plate blank.

[0015] The insulation layer has a keyway-shaped cross-section and is a hollow block with a smooth inner surface.

[0016] The electromagnetic induction coil has a keyway-shaped cross-section. It is formed by arranging and winding electromagnetic coil wires. The two ends of the electromagnetic coil wires are connected to a high-frequency induction power source, and the outer surface of the electromagnetic coil wires has an insulating layer.

[0017] The radiant heating block is set inside the insulation layer, the insulation layer is set inside the electromagnetic induction coil, and there is a sandwich between the radiant heating block and the insulation layer. The temperature sensor is set on the surface of the radiant heating block in the sandwich. The cross-sectional direction and the length extension direction of the radiant heating block, the insulation layer and the electromagnetic induction coil are consistent.

[0018] Furthermore, the conveying device includes two chains and two hanging beams.

[0019] Two hanging beams are set parallel to each other on the same plane, with the two ends of the two hanging beams respectively set on the heating device bracket, and the two hanging beams are set on opposite sides of the radiant heating block along its length.

[0020] Two chains are set parallel to each other on the same plane, with each end of the chain rotatably mounted on the corresponding end of the hanging beam, and the central axis of the chain is perpendicular to the central axis of the hanging beam.

[0021] The chain is driven by a chain motor to rotate around the suspension beam; the chain is made of insulating and high-temperature resistant high-temperature ceramic.

[0022] The high-frequency induction power supply is connected to the electromagnetic induction coil.

[0023] The heating device bracket serves as the support for the entire equipment.

[0024] Furthermore, the electromagnetic coil wire is hollow inside, and the electromagnetic coil wire and the temperature control system constitute the water cooling system of the heating device.

[0025] Furthermore, the inner surface of the radiant heating block is rough;

[0026] The material used to manufacture the radiant heating block is a cobalt alloy.

[0027] Furthermore, the length of the temperature sensors arranged along the width direction of the sheet metal blank is denoted as D. A The length of the temperature sensors arranged along the length of the sheet material is denoted as D. L D A It is half the width of the sheet blank, i.e., A1 / 2; D L It is half the length of the sheet blank, i.e., L1 / 2.

[0028] A method for electromagnetic indirect rapid heating of thin-walled titanium alloy components, wherein the method employs electromagnetic induction to heat a radiant heating block, obtaining a high-temperature radiant heating block which is then used as a heat energy medium to radiate heat the titanium alloy material; wherein the radiant heating block can generate an eddy current effect; specifically implemented through the following steps:

[0029] Step 1: Spray coating the surface of the sheet material;

[0030] Boron nitride spray is applied to the surface of the sheet metal blank.

[0031] Step 2: Use electromagnetic induction to heat the radiant heating block and maintain it at a constant temperature;

[0032] Start the electromagnetic coil water cooling system installed inside the electromagnetic coil;

[0033] A high-frequency induction power supply is activated to provide high-frequency alternating current to the electromagnetic coil wires; and nine temperature sensors at different locations are used to detect the temperature of the radiant heating block. The length of the temperature sensors arranged along the width of the sheet material is denoted as D. AThe length of the temperature sensors arranged along the length of the sheet material is denoted as D. L D A It is half the width of the sheet blank, i.e., A1 / 2; D L It is half the length of the sheet blank, i.e., L1 / 2;

[0034] Heat the radiant heating block 2 to the set temperature T. 加热块 And during the heating process, the temperature of the measuring point where the temperature sensor 9 is located is maintained within 10% of the required temperature range;

[0035] Step 3: Rapidly heat the sheet material using radiation;

[0036] The chain motor is started, and during the intermittent intervals of the chain motor, the sheet metal blank is placed in its initial position on the chain outside the radiant heating block. Then, during the chain motor's conveying phase, the sheet metal blank is fed into the radiant heating block. Next, during the next intermittent interval of the chain motor, the sheet metal blank inside the radiant heating block is heated within the heating range. Finally, during the chain motor's conveying phase, the sheet metal blank is discharged from the radiant heating block.

[0037] The stage in which the sheet metal blank is placed in its initial position on the chain located outside the radiant heating block is denoted as t, which is the intermittent time of the motor. 间歇 The stage of feeding the sheet metal blank into or out of the radiant heating block is considered the motor transport time, denoted as t. 运送 The heating time, denoted as t, is defined as the period during which the sheet material within the radiant heating block heats up within the heating range. 加热 Motor intermittent time t 间歇 Heating time t of the board 加热 Similarly, the motor delivery time t 运送 For the accuracy range of heating time for the sheet metal (t) 精度范围 Half of;

[0038] The chain motor is an intermittent motor;

[0039] For different heating rate requirements, the following heating schemes are designed:

[0040] Temperature T of the heating block 加热块 Set to the upper limit of the plate temperature range, i.e., T. 目标 +θ, and maintain a constant temperature during the heating process through a temperature feedback system; motor intermittent time t 间歇 Obtained through the following formula:

[0041]

[0042]

[0043]

[0044] In the formula, σ0 is the blackbody radiation constant, with a value of 5.6697 × 10⁻⁶. -8 W / (m 2 ·K 4 );ε 板 The emissivity of the board blank is related to the board temperature, surface quality, and material; ε 加热块 The emissivity of the radiant heating block is determined by its temperature, surface quality, and material; C is the specific heat of the plate; ρ is the density of the plate; D is the thickness of the plate; T 加热块 The heating block is kept at a constant temperature; T 板材 (t=0) represents the initial temperature of the plate; T 板材 (t) represents the temperature of the material at time t; the shortest interval of the motor is the temperature at which the material reaches the lower limit of the heating requirement, i.e.:

[0045]

[0046]

[0047] Furthermore, when it is necessary to further reduce the minimum intermittent time t of the motor... 最短间歇 When this happens, the following scheme to shorten the heating time is implemented: specifically, the heating block temperature T is reduced. 加热块 The design temperature is set above the temperature range of the sheet metal blank, and is maintained at a constant temperature during the heating process through a temperature feedback system; new motor intermittent time t 间歇 Based on the shortest interval time, the delivery time of the new motor is new t 运送 New t with motor intermittent time 间歇 for:

[0048]

[0049]

[0050]

[0051]

[0052] Furthermore, during the spraying process on the surface of the sheet blank described in step one, black powder needs to be added to the boron nitride spray to further improve the blackness of the sheet blank; the black powder is selected from carbon powder or iron powder.

[0053] The beneficial effects of this invention are as follows:

[0054] This invention utilizes electromagnetic induction to heat a ring-shaped radiant heating block that easily generates eddy currents. The high-temperature heating block then radiates heat onto a titanium alloy sheet, achieving rapid indirect electromagnetic induction heating of thin-walled titanium alloy sheets. Furthermore, the surface roughness of the heating block can be adjusted to suit different titanium alloy materials. This invention can achieve rapid indirect electromagnetic induction heating of a TC4 sheet with a thickness of 2mm, a length of 300mm, a width of 200mm, and a surface emissivity of 0.2 from room temperature (20℃) to 900℃ within 60 seconds, with an accuracy controlled within ±5℃. Attached Figure Description

[0055] Figure 1 This is a schematic diagram of the overall structure of the heating equipment involved in the present invention;

[0056] Figure 2 This is a schematic diagram (partially cut open) of the heating system involved in the present invention;

[0057] Figure 3 This is a schematic diagram of temperature control of a radiant heating block according to the present invention.

[0058] Figure 4 This is a schematic cross-sectional view of the plate blank as described in the present invention when it is located inside the heating system;

[0059] Figure 5 This is a schematic cross-sectional view of the electromagnetic induction coil involved in the present invention;

[0060] Figure 6 This is a schematic diagram showing the length dimensions of the sheet metal blank and heating system involved in the present invention.

[0061] Figure 7 This is a schematic diagram of the overall structure of the heating device with a heat-insulating cover involved in the present invention;

[0062] In the diagram, 1-plate blank; 2-radiant heating block; 3-insulation layer; 4-electromagnetic coil wire; 5-insulation layer; 6-conveying device; 61-hanging beam; 62-chain; 7-high frequency AC power supply; 8-heating device bracket; 9-temperature sensor; 10-insulation cover. Detailed Implementation

[0063] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Specific implementation method one:

[0065] This embodiment provides an electromagnetic indirect rapid heating device for thin-walled titanium alloy components, such as... Figure 1 As shown, its components include a heating system, a conveying device 6, a high-frequency induction power supply 7, a heating device support 8, and a set of temperature sensors 9.

[0066] The heating device bracket 8 is the supporting part of the entire equipment;

[0067] The high-frequency induction power supply 7 is located at the bottom of the heating device bracket 8;

[0068] The heating system is positioned above the high-frequency induction power supply 7, and the interior of the heating system is hollow.

[0069] The conveying device 6 is used to carry the sheet metal blank 1. The middle part of the conveying device 6 is located inside the heating system, and both ends of the conveying device 6 are located outside the heating system, and both ends of the conveying device 6 are mounted on the heating device bracket 8; temperature sensors 9 are arranged in a dot matrix on the heating system; wherein,

[0070] like Figure 2 As shown, the heating system includes a radiant heating block 2, an insulation layer 3, and an electromagnetic induction coil;

[0071] The radiant heating block 2 has a keyway-shaped cross-section and is a hollow block. The hollow part is used to accommodate the conveying device 6 and the plate blank 1.

[0072] The insulation layer 3 has a keyway-shaped cross-section and is a hollow block. Its inner surface is smooth to reduce radiative heat exchange with the radiant heating block 2. The insulation layer 3 is made of insulating material. Figure 1 In the diagram, D3 represents the thickness of the insulation layer 3, and D4 represents the distance between the insulation layer 3 and the radiant heating block 2.

[0073] The dimensions of the heating system are designed as follows: Figure 6 As shown, let L1 be the length of the billet, L2 be the length of the radiant heating block 2, and L3 be the length of the insulation layer 3. The selection of the length L2 of the radiant heating block 2 is related to the internal space height H of the radiant heating block 2, and the relationship is as follows:

[0074] L2 = L1 + N × H, 2 ≤ N ≤ 6

[0075] The length L3 of the insulation layer 3 is related to the thickness D3 of the insulation layer 3 and the distance D4 between the insulation layer 3 and the radiant heating block 2, and the relationship is as follows:

[0076] L3 = L2 + 2 × (D3 + D4);

[0077] The electromagnetic induction coil has a keyway-shaped cross-section. The electromagnetic induction coil is formed by arranging and winding electromagnetic coil wires 4. The two ends of the electromagnetic coil wires 4 are connected to a high-frequency induction power supply 7. The outer surface of the electromagnetic coil wires 4 is covered with an insulating layer 5.

[0078] The radiant heating block 2 is disposed inside the insulation layer 3, the insulation layer 3 is disposed inside the electromagnetic induction coil, there is a sandwich between the radiant heating block 2 and the insulation layer 3, and the temperature sensor 9 is disposed on the surface of the radiant heating block 2 in the sandwich and located on the upper surface of the radiant heating block 2; the cross-sectional direction and the length extension direction of the radiant heating block 2, the insulation layer 3 and the electromagnetic induction coil are consistent.

[0079] The electromagnetic coil wire 4 is hollow inside. The electromagnetic coil wire 4 and the temperature control system together form a water-cooling system for the heating device, reducing heat accumulation in the electromagnetic induction coil during energization. The electromagnetic coil wire 4 is made of copper.

[0080] Figure 5 In this context, R1 is the inner radius of the electromagnetic coil wire 4 of the electromagnetic induction coil, R2 is the outer radius of the electromagnetic coil wire 4 of the electromagnetic induction coil, and R3 is the outer radius of the insulation layer 5 of the electromagnetic induction coil.

[0081] By rationally coordinating the electromagnetic coil wire 4 with the radiant heating block 2, the electromagnetic induction efficiency is improved, solving the problem of energy utilization rate of titanium alloy materials using electromagnetic heating. This enables indirect electromagnetic induction rapid heating of titanium alloy plates, resulting in faster heating speed and higher temperature uniformity, thus achieving better material microstructure control.

[0082] The conveying device 6 includes two chains 61 and two hanging beams 62.

[0083] Two hanging beams 62 are arranged in parallel on the same plane. The two ends of the two hanging beams 62 are respectively set on the heating device bracket 8. The two hanging beams 62 are respectively set on opposite sides of the radiant heating block 2 in the length direction.

[0084] Two chains 61 are set parallel to each other on the same plane, and the two ends of each chain 61 are rotatably set on the corresponding end of the hanging beam 62. The central axis of the chain 61 is perpendicular to the central axis of the hanging beam 62.

[0085] The chain 61 is driven by a chain motor to rotate around the hanging beam 62, so that the chain 61 can move inside the radiant heating block 2, so as to transfer the plate blank 1 carried on the chain 61 into the radiant heating block 2 or to remove the chain 61 from the radiant heating block 2.

[0086] The chain 61 is made of insulating and high-temperature resistant high-temperature ceramic.

[0087] The high-frequency induction power supply 7 is connected to the electromagnetic induction coil, and the high-frequency induction power supply 7 is located at the bottom of the heating device bracket 8.

[0088] The heating device bracket 8 serves as the support for the entire equipment; an insulation cover 10 is also installed on the top of the heating device bracket 8. Specific Implementation Method Two:

[0090] Unlike the first embodiment, the inner surface of the radiant heating block 2 in the electromagnetic indirect rapid heating device for thin-walled titanium alloy components in this embodiment is rough (e.g., a frosted surface) to improve the ambient blackness of radiant heat transfer, and the outer surface of the radiant heating block 2 is smooth to reduce heat loss from the radiant heating block 2.

[0091] like Figure 4 As shown, A1 is the width of the sheet blank 1, D1 is the thickness of the sheet blank 1; A2 is the width of the straight edge area of ​​the radiant heating block 2 or the distance between the centers of the two sides; H is the internal height of the keyway-shaped radiant heating block 2; D2 is the thickness of the radiant heating block 2; Radiant block design method: 1. The width A2 of the straight edge area of ​​the radiant heating block 2 is not less than the maximum width A1 of the sheet blank 1; 2. The height H of the radiant heating block 2 is 0.1 to 0.5 times the width A2 of the straight edge area of ​​the radiant heating block 2; 3. The thickness D2 of the radiant heating block 2 is between 5mm and 20mm.

[0092] The material used to manufacture the radiant heating block 2 is a cobalt alloy;

[0093] When the forming temperature of the sheet is below 700℃, iron is selected as the material for induction heating of the radiant heating block 2; when the forming temperature of the sheet is above 700℃, cobalt is selected as the material for induction heating of the radiant heating block 2 to prevent excessively high temperatures from reducing or eliminating the paramagnetism of the material. Specific implementation method three:

[0095] Unlike Specific Embodiment Two, in this embodiment, the temperature sensor 9 of the electromagnetic indirect rapid heating device for thin-walled titanium alloy components is arranged along the width direction of the sheet metal blank 1, with the length denoted as D. A The length of the temperature sensors 9 arranged along the length of the sheet metal blank 1 is denoted as D. L D A It is half the width of plate blank 1, i.e., A1 / 2; D L It is half the length of the sheet blank 1, i.e., L1 / 2. Specific implementation method four:

[0097] Unlike the third embodiment, in this embodiment, the thickness D3 of the insulation layer 3 of the thin-walled titanium alloy component electromagnetic indirect rapid heating device is in the range of 10mm to 50mm; and the distance D4 between the insulation layer 3 and the radiant heating block 2 is in the range of 2mm to 10mm. Specific implementation method five:

[0099] This embodiment discloses an electromagnetic indirect rapid heating method for thin-walled titanium alloy components. The method employs electromagnetic induction to heat a radiant heating block, obtaining a high-temperature radiant heating block which serves as the heat energy medium. This heat energy medium is then used to radiate heat the titanium alloy material. The radiant heating block generates an eddy current effect. A ring-shaped material is used as the energy medium to more efficiently convert the energy of the electromagnetic coil into the internal energy of the ring-shaped material. This energy is then conducted to the thin-walled titanium alloy component via radiative heat transfer. This method solves the problem of low electromagnetic heating energy conversion rate caused by the low impedance of the electromagnetic coil due to the difficulty in generating an eddy current effect in thin-walled titanium alloy components. Specifically, this is achieved through the following steps:

[0100] Step 1: Spray coating the surface of the sheet blank 1;

[0101] Step 2: Use electromagnetic induction to heat the radiant heating block 2 and maintain it at a constant temperature;

[0102] Start the electromagnetic coil water cooling system installed inside the electromagnetic coil;

[0103] The high-frequency induction power supply 7 is activated to supply high-frequency alternating current to the electromagnetic coil wire 4; and the temperature of the radiant heating block 2 is detected using nine temperature sensors 9 at different locations, such as... Figure 3 As shown, the length of the temperature sensor 9 arranged along the width direction of the plate blank 1 is denoted as D. A The length of the temperature sensors 9 arranged along the length of the sheet metal blank 1 is denoted as D. L D A It is half the width of plate blank 1, i.e., A1 / 2; D L It is half the length of the sheet blank 1, i.e., L1 / 2;

[0104] Heat the radiant heating block 2 to the set temperature T. 加热块 And during the heating process, the temperature of the measuring point where the temperature sensor 9 is located is maintained within 10% of the required temperature range;

[0105] The temperature sensor 9 achieves temperature control through various existing automatic temperature control systems, and takes the average temperature of the measurement points where the temperature sensor 9 is located. After all the temperature measurement points reach 90% of the set temperature, the power is reduced until all the temperature measurement points enter the set temperature range.

[0106] Step 3: Perform rapid radiant heating on the sheet blank 1;

[0107] The chain motor is started, and during the intermittent interval of the chain motor, the sheet metal blank 1 is placed in its initial position on the chain 61 located outside the radiant heating block 2; then, during the motor transport phase of the chain motor, the sheet metal blank 1 is fed into the radiant heating block 2; then, during the next electrode intermittent interval of the chain motor, the sheet metal blank 1 inside the radiant heating block 2 is heated within the heating range; then, during the motor transport phase of the chain motor, the sheet metal blank 1 is discharged from the radiant heating block 2; wherein,

[0108] The initial position of the sheet metal blank 1 on the chain 61 located outside the radiant heating block 2 is denoted as t, which is the motor intermittent time. 间歇 The stage in which the sheet material 1 is fed into or out of the radiant heating block 2 is taken as the motor transport time and denoted as t. 运送 The period during which the sheet material 1 within the radiant heating block 2 heats up within the heating range is defined as the sheet material heating time, denoted as t. 加热 Motor intermittent time t 间歇 Heating time t of the board 加热 Similarly, the motor delivery time t 运送 For the accuracy range of heating time for the sheet metal (t) 精度范围 Half of the heating time of the board t 加热 and the accuracy range of heating time for the sheet metal (t) 精度范围 Provided based on the heating scheme adopted;

[0109] The chain motor is an intermittent motor;

[0110] For different heating rate requirements, the following heating schemes are designed:

[0111] Temperature T of the heating block 加热块 Set to the upper limit of the plate temperature range, i.e., T. 目标 +θ, and maintain a constant temperature during the heating process through a temperature feedback system; this scheme has no specific requirements for the motor's operating time, the shorter the motor's operating time, the better; motor intermittent time t 间歇 Obtained through the following formula:

[0112]

[0113]

[0114]

[0115] In the formula, σ0 is the blackbody radiation constant, with a value of 5.6697 × 10⁻⁶. -8 W / (m 2 ·K4 );ε 板 The emissivity of the board blank 1 is related to the board temperature, surface quality, and material of the board; ε 加热块 The emissivity of the radiant heating block is 2, and its value depends on the temperature, surface quality, and material of the heating block; C is the specific heat of the plate; ρ is the density of the plate; D is the thickness of the plate; T 加热块 The heating block is kept at a constant temperature; T 板材 (t=0) represents the initial temperature of the plate; T 板材 (t) represents the temperature of the material at time t; the shortest interval of the motor is the temperature at which the material reaches the lower limit of the heating requirement, i.e.:

[0116]

[0117] Specific implementation method six:

[0119] Unlike Specific Embodiment Five, this embodiment provides an electromagnetic indirect rapid heating method for thin-walled titanium alloy components, which further includes the following steps:

[0120] When it is necessary to further reduce the minimum interval time t of the motor. 最短间歇 When this happens, the following scheme to shorten the heating time is implemented: specifically, the heating block temperature T is reduced. 加热块 The design temperature is set to be higher than the temperature range of the sheet metal blank, and a temperature feedback system is used to maintain a constant temperature during the heating process. In this scheme, the feeding and unloading time of the sheet metal affects the temperature accuracy, therefore, there are certain requirements for the motor's operating time and motor intermittent time. The new motor intermittent time is t. 间歇 Based on the shortest interval time, the delivery time of the new motor is new t 运送 With the new motor interval time new t 间歇 for:

[0121]

[0122]

[0123]

[0124]

[0125] This invention utilizes thermal radiation to transfer heat. Based on the different heating rates of different material parameters (caused by the differences in density and specific heat of different materials), different surface roughnesses of the radiant heating blocks 2 are selected for radiant heat transfer. Therefore, the method of this invention is applicable to the heating of all titanium alloy materials. Specific implementation method seven:

[0127] Unlike specific embodiments five or six, in the process of spraying the surface of the plate blank 1 in step one of the electromagnetic indirect rapid heating method for thin-walled titanium alloy components in this embodiment, black powder is added to the boron nitride spray to make its blackness reach 0.98, so as to further improve the blackness of the plate blank 1; the black powder is selected from carbon powder or iron powder, wherein carbon powder is suitable for vacuum environment, and iron powder is suitable for normal conditions.

[0128] Example 1 describes an electromagnetic indirect rapid heating method for thin-walled titanium alloy components.

[0129] A rapid indirect electromagnetic induction heating method based on radiative heat transfer was developed to heat a TC4 plate with a thickness of 2mm, a length of 300mm, a width of 200mm, and a surface emissivity of approximately 1 from room temperature (20℃) to 900℃ within 60 seconds, with an accuracy controlled within ±5℃. The method is implemented according to the following device design and heating process:

[0130] The device is designed as follows:

[0131] For the plate material that requires rapid heating, the heating block is selected in the shape of a keyway, which consists of two straight edges parallel to the plate material and two semicircles on the side. The plate width A1 is 200mm; the width of the straight edge area of ​​the heating block A2 is 200mm; the height of the heating block H is 60mm; the plate thickness D1 is 2mm; and the heating block thickness D2 is 10mm.

[0132] Before starting the rapid heating device, the surface of the sheet blank is first treated with a surface spraying treatment. The main purpose of the spraying is to improve the blackness of the sheet and accelerate the heat exchange rate. This step can be combined with surface treatments in other processes to achieve the effects of rapid heat transfer, anti-oxidation, and lubrication during forming. Typically, boron nitride spray is applied to the surface of sheet blank 1, at which point the blackness of sheet blank 1 reaches 0.95.

[0133] The blackness of the sheet blank 1 is 1.

[0134] The thickness of the insulation layer 3, D3, is 20mm, and the distance between the insulation layer 3 and the heating block, D4, is 5mm.

[0135] The inner radius R1 of the electromagnetic coil is 3mm, the outer radius R2 of the electromagnetic coil is 4mm, and the outer radius R3 of the electromagnetic coil insulation layer is 5mm.

[0136] The length L1 of the plate blank 1 is 300mm, the length L2 of the radiant heating block is 420mm, and the length L3 of the insulation layer is 470mm.

[0137] Assemble the heating system described above, and design the conveyor chain, high-frequency AC power supply, heating device bracket, and protective shell according to the actual dimensions of the heating coil. The conveyor chain is made of ceramic; the high-frequency AC power supply is a low-voltage, high-current power supply with a current frequency of 1–100 kHz. Before operation, the frequency at which the impedance is highest is used for testing, and this highest impedance is used as the operating frequency for heating.

[0138] The heating process is as follows:

[0139] Before starting the rapid heating device, spray the surface of the plate with boron nitride spray containing black powder.

[0140] The water cooling system of the electromagnetic coil is started. The water flow rate is determined by the ambient temperature and the Joule heat of the electromagnetic coil. A feedback system is usually used to adjust and determine it to ensure that the water temperature is always kept below 50°C.

[0141] The electromagnetic coil power supply is activated, and high-frequency alternating current is applied. Nine temperature sensors at different locations are used to detect the temperature of the heating block. The width of each temperature sensor is spaced D... A The distance D along the length of the temperature sensor is 200mm. L The measurement point is 300mm. When the temperature accuracy at the above measurement point reaches ±0.5℃, the billet can be rapidly heated by radiation.

[0142] The conveyor chain motor is started, and the sheet material is placed in the initial position during the intermittent phase of the conveyor chain. Using Scheme 1, the shortest heating time is calculated to be 57 seconds, which meets the heating requirements. Therefore, Scheme 1 is adopted for temperature control, and the motor intermittent time t... 间歇 It takes 57.0 seconds.

[0143] The above steps can achieve rapid heating of a TC4 board with a thickness of 2mm, a length of 300mm, a width of 200mm, and a surface emissivity of 0.2 from room temperature (20℃) to 900℃ within 60s, with an accuracy controlled within ±5℃, using indirect electromagnetic induction based on radiative heat transfer.

[0144] Example 2:

[0145] This embodiment provides an electromagnetic indirect rapid heating method for thin-walled titanium alloy components. Unlike Embodiment 1, the heating block thickness D2 in the heating device is 20mm. Otherwise, it is the same as Specific Embodiment 1, in order to achieve higher temperature precision control and thus realize the heating of temperature-sensitive metals.

[0146] Example 3:

[0147] This embodiment of the electromagnetic indirect rapid heating method for thin-walled titanium alloy components differs from Embodiment 1 in that the insulation layer thickness D3 in the heating device is 50mm, while the rest is the same as in Specific Embodiment 1, in order to meet the requirements of higher energy utilization and high-efficiency heating of metals, thereby achieving the requirements of green and environmentally friendly practices.

[0148] Example 4:

[0149] This embodiment of the electromagnetic indirect rapid heating method for thin-walled titanium alloy components differs from Embodiment 1 in that: a support strip is added to the conveyor chain in the heating equipment, and the motor intermittent time in step four is 114.0s. The rest is the same as in Specific Embodiment 1, in order to meet higher high-temperature billet precision and thus achieve the forming of high-precision components.

[0150] Example 5:

[0151] This embodiment of the electromagnetic indirect rapid heating method for thin-walled titanium alloy components differs from Embodiment 1 in that the heating block temperature is set to 950°C, the motor travel time is 0.67s, the motor intermittent time is 32.5s, and other aspects are the same as in Specific Embodiment 1, in order to meet the requirements of higher heating rate and thus achieve better material microstructure control.

[0152] Example 6:

[0153] This embodiment of the electromagnetic indirect rapid heating method for thin-walled titanium alloy components differs from Embodiment 1 in that the heating block temperature is set to 1100℃, the motor transport time is 0.07s, the motor intermittent time is 18.4s, and the rest is the same as in Specific Embodiment 1, in order to meet the requirements of extremely high heating rate and thereby achieve extreme material microstructure control.

[0154] The embodiments disclosed herein are preferred embodiments, but are not limited thereto. Those skilled in the art can readily grasp the spirit of the present invention based on the above embodiments and make different extensions and variations, but as long as they do not depart from the spirit of the present invention, they are all within the protection scope of the present invention.

Claims

1. An electromagnetic indirect rapid heating device for thin-walled titanium alloy components, characterized in that: Its components include a heating system, a conveying device (6), a high-frequency induction power supply (7), a heating device support (8), and a set of temperature sensors (9). The heating system is located above the heating device support (8), and the interior of the heating system is hollow; The conveying device (6) is used to carry the sheet metal blank (1). The middle part of the conveying device (6) is located inside the heating system, and the two ends of the conveying device (6) are located outside the heating system. The two ends of the conveying device (6) are mounted on the heating device support. The temperature sensor (9) is installed on the heating system. The heating system includes a radiant heating block (2), an insulation layer (3), and an electromagnetic induction coil; The radiant heating block (2) has a keyway-shaped cross-section and is a hollow block. The hollow part is used to accommodate the conveying device (6) and the plate blank (1). The thermal insulation layer (3) has a keyway-shaped cross-section and is a hollow block with a smooth inner surface. The electromagnetic induction coil has a keyway-shaped cross-section. The electromagnetic induction coil is formed by arranging and winding electromagnetic coil wires (4). The two ends of the electromagnetic coil wires (4) are connected to a high-frequency induction power supply (7). The outer surface of the electromagnetic coil wires (4) has an insulating layer (5). The radiant heating block (2) is set inside the insulation layer (3), the insulation layer (3) is set inside the electromagnetic induction coil, there is a sandwich between the radiant heating block (2) and the insulation layer (3), and the temperature sensor (9) is set on the surface of the radiant heating block (2) in the sandwich; the cross-sectional direction and the length extension direction of the radiant heating block (2), the insulation layer (3) and the electromagnetic induction coil are consistent; The conveying device (6) includes two chains (61) and a hanging beam (62). Two hanging beams (62) are set parallel to each other on the same plane. The two ends of the two hanging beams (62) are respectively set on the heating device bracket (8). The two hanging beams (62) are respectively set on opposite sides of the radiant heating block (2) in the length direction. Two chains (61) are set parallel to each other on the same plane. The two ends of each chain (61) are rotatably set on the corresponding end of the hanging beam (62). The central axis of the chain (61) is perpendicular to the central axis of the hanging beam (62). The chain (61) is driven by a chain motor to rotate around the hanging beam (62); the chain (61) is made of insulating and high-temperature resistant high-temperature ceramic. The high-frequency induction power supply (7) is connected to the electromagnetic induction coil; The heating device bracket (8) is the supporting part of the entire equipment.

2. The electromagnetic indirect rapid heating device for thin-walled titanium alloy components according to claim 1, characterized in that: The inner surface of the radiant heating block (2) is rough, and the outer surface of the radiant heating block (2) is smooth; The material used to make the radiant heating block (2) is a cobalt alloy.

3. An electromagnetic indirect rapid heating device for thin-walled titanium alloy components according to claim 1 or 2, characterized in that: The length of the temperature sensor (9) arranged along the width direction of the plate blank (1) is denoted as D. A The length of the temperature sensor (9) arranged along the length of the plate blank (1) is denoted as D. L D A The width of the sheet blank (1) is half, i.e., A1 / 2; D L It is half the length of the sheet blank (1), i.e., L1 / 2.

4. A heating method using the electromagnetic indirect rapid heating device for thin-walled titanium alloy components according to any one of claims 1-3, characterized in that: The aforementioned electromagnetic indirect rapid heating method uses electromagnetic induction to heat a radiant heating block, obtaining a high-temperature radiant heating block which is then used as a heat energy medium to radiate heat the titanium alloy material. The radiant heating block can generate an eddy current effect. This is achieved through the following steps: Step 1: Spray coating the surface of the sheet blank (1); Boron nitride spray is applied to the surface of the sheet blank (1); Step 2: Use electromagnetic induction to heat the radiant heating block (2) and maintain it at a constant temperature; Start the electromagnetic coil water cooling system installed inside the electromagnetic coil; The high-frequency induction power supply (7) is activated to supply high-frequency alternating current to the electromagnetic coil wire (4); and the temperature of the radiant heating block (2) is detected by nine temperature sensors (9) at different locations. The length of the temperature sensors (9) arranged along the width direction of the plate blank (1) is denoted as D. A The length of the temperature sensor (9) arranged along the length of the plate blank (1) is denoted as D. L D A The width of the sheet blank (1) is half, i.e., A1 / 2; D L It is half the length of the sheet blank (1), i.e., L1 / 2; Heat the radiant heating block (2) to the set temperature. And during the heating process, the temperature of the measuring point where the temperature sensor (9) is located is kept within 10% of the required temperature range; Step 3: Radiation-induced rapid heating of the sheet material (1); The chain motor is started, and during the intermittent time of the chain motor, the sheet metal blank (1) is placed in an initial position on the chain (61) located outside the radiant heating block (2); then, during the motor transport phase of the chain motor, the sheet metal blank (1) is fed into the radiant heating block (2); then, during the next intermittent time of the chain motor, the sheet metal blank (1) inside the radiant heating block (2) is heated within the heating range; then, during the motor transport phase of the chain motor, the sheet metal blank (1) is sent out of the radiant heating block (2); wherein, The initial position of the sheet metal blank (1) on the chain (61) located outside the radiant heating block (2) is denoted as the motor intermittent time. The stage in which the sheet blank (1) is fed into or out of the radiant heating block (2) is taken as the motor transport time and expressed as follows: The stage during which the sheet material (1) within the radiant heating block (2) heats up within the heating range is taken as the sheet heating time, and is expressed as: Motor intermittent time Heating time of the board Similarly, the motor delivery time For the accuracy range of heating time of the sheet material Half of; The chain motor is an intermittent motor; For different heating rate requirements, the following heating schemes are designed: Temperature of the heating block Set to the upper limit of the board temperature range, i.e. The system maintains a constant temperature during the heating process via a temperature feedback system; motor intermittent time. Obtained through the following formula: ； ； In the formula, Let be the blackbody radiation constant, with a value of . ; The value of the blackness of the board blank (1) is related to the board temperature, board surface quality and board material; The emissivity of the radiant heating block (2) is related to the temperature of the heating block, the surface quality of the heating block, and the material of the heating block; C Specific heat of the sheet metal; ρ This refers to the density of the board material. D The thickness of the sheet material; Maintain a constant temperature for the heating block; The initial temperature of the board material; For the board material t The temperature at any given moment; the shortest interval between motor cycles is the temperature at which the material reaches the lower limit of the required heating temperature, i.e.: ; 。 5. The electromagnetic indirect rapid heating method for thin-walled titanium alloy components according to claim 4, characterized in that: The heating method further includes the following steps: when it is necessary to further reduce the shortest interval time of the motor. At that time, the following scheme to shorten the heating time will be implemented: specifically, the temperature of the heating block will be reduced. The design temperature is set to be higher than the temperature range of the sheet metal blank (1), and is maintained at a constant temperature through a temperature feedback system during the heating process; new motor intermittent time. Based on the shortest interval time, the delivery time of the new motor is new. With the new motor interval time for: ; ; ; 。 6. A method for electromagnetic indirect rapid heating of thin-walled titanium alloy components according to claim 4 or 5, characterized in that: In the process of spraying the surface of the board blank (1) as described in step one, black powder needs to be added to the boron nitride spray to further improve the blackness of the board blank (1). The black powder is selected from graphite powder, carbon powder, or iron powder.

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