Multifunctional simulation plate thermoforming test device

Abstract

The invention relates to a multifunctional simulation plate hot forming test device in the technical field of metal plate hot stamping. The multifunctional simulation plate hot forming test device comprises a working and rapid heating device, a loading device with a replaceable die, a clamping device, a stretching system, a lubrication temperature measuring device, a PLC control system, a data acquisition system and the like. The rapid heating device, the lubricating temperature measuring device, the loading device with the replaceable die and the stretching system are sequentially connected and installed on the workbench, the clamping device is installed on a sliding table of the stretching system, the hydraulic system provides accurate pressure for the device, and the whole device is controlled and supervised through the PLC control system. According to the invention, the sheet metal is heated in a contact heating mode through the rapid heating device, different dies are used in cooperation with the loading device capable of replacing the dies, the processes of forming, stretching, friction and the like of hot stamping of the sheet metal are simulated, and then different high-temperature performances of the sheet metal are researched.

Description

Technical Field

[0001] The invention relates to the technical field of metal sheet hot stamping, in particular to a multifunctional simulated sheet hot forming test device. Background Art

[0002] In the hot stamping process, it is necessary to study many high-temperature properties of the sheet metal, such as high-temperature tensile tests, high-temperature friction tests, high-temperature forming tests, and high-temperature deep drawing tests. This is to explore the sheet metal's stress-strain curve, friction coefficient, resilience, and forming limit at high temperatures. High-temperature performance affects whether qualified products can be produced, whether the product will wrinkle or crack, and will affect the product's rebound prediction. As a device used in hot stamping research, high-temperature testing machines that simulate sheet metal hot stamping are constantly expanding in variety and function.

[0003] At present, there are few studies on high-temperature testing machines that simulate the rapid heating of sheet metal during hot stamping in China. They have the following common disadvantages: First, most heating methods use furnace heating. For aluminum alloy hot stamping technology, contact heating is used in actual production. Because aluminum alloy has low heating efficiency under the heating method of thermal radiation, high-efficiency production cannot be achieved; second, the module of the high-temperature testing machine is single, and the research on the high-temperature performance of the sheet metal is single, and it is impossible to achieve research on different high-temperature properties by changing the mold.

[0004] An existing plate-belt high-temperature friction and wear testing machine was applied for by Shanghai University, with patent publication number CN105510166A. The testing machine is mainly composed of a heating furnace, a loading device and a stretching device. The stretching device is composed of a ball screw and a motor. The loading device is located between the heating furnace and the stretching device, and the motor is connected to the ball screw through a coupling. Its structure is significantly different from that of the present invention; a stamping friction and wear testing machine with patent publication number CN117969238A has expandable functions and the mold can be heated to meet the requirements of both cold mold and cold plate and hot mold and cold plate processes. Its structure is significantly different from that of the present invention; a heatable metal plate friction coefficient testing device and method with patent publication number CN111487186A measures the friction coefficient between the mold and the part during hot forming of metal sheet metal by heating the specimen in a heating furnace and independently heating the mold. Its structure is significantly different from that of the present invention.

[0005] Therefore, the existing high-temperature testing machines for simulating sheet metal hot stamping need to improve the heating method and experimental research performance diversity, as well as the stretching method and pressure loading method. To this end, we propose a multifunctional simulated sheet metal hot forming test device. Summary of the Invention

[0006] In view of the defects existing in the prior art, the purpose of the present invention is to achieve the above purpose. The technical solution adopted by the present invention is: to make technical improvements to the high-temperature testing machine that simulates hot stamping of sheet metal, mainly to improve the heating method and its temperature control method to achieve a rapid heating method that conforms to actual production; to improve the stretching method and pressure loading method to achieve high-speed sliding and large-load pressurization, etc.; to improve the single module of the high-temperature testing machine, and to achieve research on different high-temperature performance by replacing the mold, etc.

[0007] The technical solution of the present invention is:

[0008] A multifunctional simulated sheet metal hot forming test device comprises a working and rapid heating device, a loading device for a replaceable die, a clamping device, a stretching system, a lubrication and temperature measuring device, a PLC control system, a data acquisition system, etc.; the rapid heating device, the lubrication and temperature measuring device, the loading device for the replaceable die, and the stretching system are sequentially connected and installed on a workbench, the clamping device is installed on a slide of the stretching system, the hydraulic system provides accurate pressure to the device, and the entire device is controlled and supervised by a PLC control system, etc.; the present invention heats the sheet metal by a contact heating method through a rapid heating device, uses different dies in conjunction with the loading device for the replaceable die, simulates the forming, stretching, friction and other processes of hot stamping of the sheet metal, and further studies the different high-temperature properties of the sheet metal.

[0009] In a further technical solution, the rapid heating device includes a hydraulic support, a detachable sheet heating mold, a heating system, a temperature measuring system and an automatic lifting device.

[0010] The hydraulic support includes a mold mounting upper plate and a lower plate, a heating pressure cylinder mounting plate, a column, a linear bearing, etc., and is used to install different heating molds and connect the hydraulic cylinder and the heating mold;

[0011] The detachable sheet heating mold includes an upper mold plate and a lower mold plate, upper and lower heating blocks, upper and lower pressure-resistant insulation plates, guide pins and sleeves, limit pins, positioning plates, insulation cotton, etc. Different heating molds can achieve rapid heating of different sheet materials;

[0012] The heating system includes a heating rod, a temperature controller, a solid-state relay, etc., which are used to heat the mold to a specified temperature;

[0013] The temperature measurement system includes a thermocouple, a temperature controller, a paperless recorder, etc., which detects the temperature of the heating mold and the temperature of the sheet;

[0014] The automatic lifting device includes an ejector pin, an ejector plate, a stepper motor, a screw rod set, etc., which is used to lift the sheet metal after heating to facilitate subsequent transfer of the sheet metal;

[0015] In a further technical solution, the loading device of the replaceable mold includes a loading bracket, a replaceable mold, a pressure sensor, etc.; the loading bracket is equipped with a loading hydraulic cylinder, and the hydraulic cylinder connecting rod is equipped with a replaceable upper mold, which is pressed together with the replaceable lower mold by the downward pressure of the hydraulic cylinder. The replaceable lower mold is connected to the pressure sensor to measure the pressure value; by replacing different molds, the different high-temperature properties of the sheet metal are experimentally studied.

[0016] In a further technical solution, the clamping device includes a clamping platform, a vertical vise and a tension sensor; the clamping platform is installed on the slide of the stretching system, a slide rail slider device is installed on the platform, the vertical vise is installed on the slider, and the tension sensor is connected to one side of the vertical vise to measure the tension value applied to the vise; by clamping a section of the sheet material, the sheet material can be stretched, slid, transferred, etc.

[0017] In a further technical solution, the stretching system includes a slide, a linear motion mechanism, and a servo motor;

[0018] The linear motion mechanism includes a reducer, a linear slide block, a gear rack, a frame, etc., and its function is to enable the sheet to slide or stretch at a certain speed, and to transfer to a specified position, etc.;

[0019] In a further technical solution, the lubrication temperature measuring device includes a lubrication system and an infrared temperature measuring system;

[0020] The lubrication system consists of a metal spray head, a solenoid valve, a pressure regulating filter and an oil tank. The spray head is installed on a metal bracket and uses compressed air to atomize the lubricating oil and spray it on the surface of the sheet metal, which can simulate the process of spraying lubricating oil on the sheet metal in actual production.

[0021] The infrared temperature measurement system consists of an infrared temperature probe, a transmitter and a paperless recorder. The infrared temperature probe is installed after the lubrication system and before the loading device of the replaceable mold, and is used to measure the temperature of the sheet metal after spraying lubricating oil.

[0022] In a further technical solution, the hydraulic loading system includes hydraulic pressurization of the rapid heating device, hydraulic loading of the loading device of the replaceable mold, and a hydraulic station containing a solenoid valve, a proportional valve, a pressure holding valve, an oil tank, an explosion-proof motor, etc. The hydraulic station is controlled by a PLC to accurately provide the set pressure to the rapid heating device, the loading device, etc.

[0023] In a further technical solution, the PLC control system includes control of the hydraulic system, control of the heating system, control of the stretching system and a data acquisition system;

[0024] The control of the hydraulic system includes the heating pressure cylinder providing a stable holding pressure to the contact-type rapid heating device, the loading pressure cylinder providing a stable and accurate loading pressure to the friction device, and controlling the holding time, pressing down and lifting of each pressure cylinder;

[0025] The control of the heating system includes a temperature controller controlling the heating rod through a solid-state relay so that the heating mold reaches a preset temperature and remains constant;

[0026] The control of the stretching system includes PLC controlling the servo electric cylinder to achieve a specified speed and a specified displacement stroke through a servo driver;

[0027] The data acquisition system includes the heating temperature rise curve of the heating block and the sheet material through the thermocouple, the actual temperature curve of the sheet material after lubrication collected by the infrared temperature measuring probe, and the actual force curve of the pressure and tension exerted on the sheet material collected by the pressure sensor and the tension sensor.

[0028] In a further technical solution, a test method of the multifunctional simulated sheet metal hot forming test device includes the following steps:

[0029] Step 1: Determine the type of experiment to be performed and install different molds in the loading device of the replaceable mold according to the needs, such as friction molds, U-shaped molds, cylindrical stretching molds, etc.

[0030] Step 2: Start the test, plug in the power, open the computer software, and reset and calibrate the initial position of the slide on the interface.

[0031] Step 3: Pass the sheet through the loading device of the replaceable mold. After determining the installation position of the sheet using the positioning plate on the contact rapid heating device, use the upper limit slot on the clamping device to determine the installation position of the other end of the sheet, and use a vertical vise to clamp the sheet.

[0032] Step 4: Open the software operation interface. Open different operation interfaces according to different experiments. For example, for friction experiments, input the test parameters, including heating mold temperature, heating and holding time, heating and holding pressure, loading pressure, and stretching sliding speed. These five parameters can be adjusted within a range.

[0033] Step 5: Start the equipment, the heating rod heats the heating mold to the corresponding temperature, and the temperature control system detects and maintains the temperature; then the hydraulic system pressurizes the sheet metal according to the specified heating and holding pressure, and after the preset holding time is reached, the mold is released, and then the automatic lifting device lifts the sheet metal;

[0034] Step 6: The movement sequence is different for different experiments. For the friction experiment, the hydraulic system pressurizes the friction die pair according to the specified loading and holding pressure, and finally starts the servo electric cylinder to pull the sheet metal for a unidirectional sliding friction test until the stroke ends. For the forming experiment, the stretching device is first started to transfer the heated sheet metal to the forming die. After positioning, the hydraulic system pressurizes the forming die pair according to the specified loading and holding pressure to form the sheet metal.

[0035] Step 7: Open the data acquisition interface. The data acquisition system can collect the heating curves of the heating block and the sheet through the thermocouple, the actual temperature curve of the sheet after lubrication through the infrared temperature probe, the actual force curve (Ft) of the tension on the sheet through the tension sensor, and the actual force curve (Pt) of the pressure on the sheet through the pressure sensor.

[0036] Step 8: After the test is completed, the loading hydraulic cylinder is lifted, the heating mold stops heating, the lifting device is reset, the fan is turned on for heat dissipation, the temperature drops to room temperature, the sheet metal is removed, and the equipment is turned off.

[0037] The beneficial effects of the present invention are:

[0038] Compared with the existing technology, this application uses a rapid heating device to heat the sheet material using contact heating, and uses different molds in conjunction with a loading device with replaceable molds to simulate the forming, stretching, friction and other processes of hot stamping of the sheet material, thereby studying the different high-temperature properties of the sheet material. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 1 is a schematic diagram of the overall structure of an embodiment of the present invention;

[0040] Figure 2 In the embodiment of the present invention Figure 1 A schematic diagram of the front structure of FIG.

[0041] Figure 3 1 is a schematic structural diagram of a rapid heating device according to an embodiment of the present invention;

[0042] Figure 4 1 is a schematic structural diagram of a lubrication temperature measuring device according to an embodiment of the present invention;

[0043] Figure 5 1 is a schematic structural diagram of a loading device for a replaceable mold according to an embodiment of the present invention;

[0044] Figure 6 1 is a schematic front view of the structure of different replaceable molds according to an embodiment of the present invention;

[0045] Figure 7 It is a schematic structural diagram of the clamping device and the stretching system according to an embodiment of the present invention.

[0046] Description of reference numerals:

[0047] 100. Rapid heating device; 110. Hydraulic support; 120. Removable sheet heating mold; 130. Automatic lifting device; 200. Loading device for replaceable mold; 210. Loading support; 220. Replaceable mold; 300. Clamping device; 400. Stretching system; 410. Linear motion mechanism; 420. Servo motor; 500. Hydraulic loading system; 510. Heating pressure cylinder; 520. Loading pressure cylinder; 600. Lubrication and temperature measuring device; 610. Lubrication system; 620. Infrared temperature measuring system. DETAILED DESCRIPTION

[0048] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0049] Example:

[0050] like Figure 1-Figure 7 As shown, a multifunctional simulated sheet metal hot forming test device includes a working, rapid heating device 100, a loading device 200 with a replaceable mold, a clamping device 300, a stretching system 400, a lubrication and temperature measuring device 600, a PLC control system, a data acquisition system, etc.; the rapid heating device, the lubrication and temperature measuring device 600, the loading device 200 with a replaceable mold and the stretching system 400 are sequentially connected and installed on the workbench, the clamping device 300 is installed on the slide of the stretching system 400, the hydraulic system 500 provides accurate pressure to the device, and the entire device is controlled and supervised using a PLC control system.

[0051] In another embodiment, the rapid heating device 100 includes a hydraulic support 110, a detachable sheet heating mold 120, a heating system, a temperature measuring system, and an automatic lifting device 130.

[0052] The hydraulic support 110 includes an intermediate mold mounting upper plate for mounting the upper mold of the heating mold, and six linear bearings mounted on the upper plate to facilitate the plate to drive the upper mold of the heating mold to move up and down to complete the mold opening and closing movements; a lower mold mounting lower plate for mounting the lower mold of the heating mold, and two uppermost heating pressure cylinder mounting plates. Columns pass through the upper and lower plates and are fixed by locking nuts. The upper and lower plates have grooves on all four sides for mounting mica plates and insulating glass, sealing the mold inside the support and isolating it from the outside world, thereby reducing heat loss and the impact of heat on the surrounding environment.

[0053] The upper heating block of the detachable sheet heating mold 120 is connected to the upper template through the upper pressure-resistant insulation board. Similarly, the lower heating block is connected to the lower template through the lower pressure-resistant insulation board. The heating block is surrounded by insulation cotton to wrap it. The pressure-resistant insulation board plays the role of bearing the pressure of the heating block and isolating the heat transfer between the heating block and the template. Like the insulation cotton, it plays the role of heat insulation and heat preservation to reduce heat loss. The guide pillars and guide sleeves, and the limit pillars are installed at the four corners of the upper and lower templates. The guide pillars and guide sleeves can position the opening and closing movement of the mold to make it open and close accurately. The limit pillars play the role of protecting the mold when it is unloaded. The positioning plate is installed in the middle of the lower template to position the installed sheet.

[0054] The heating system includes a heating rod, a temperature controller, a solid-state relay, etc. The heating rod is embedded in the upper and lower heating blocks. The solid-state relay and the temperature controller are used to control the heating of the heating rod, thereby heating the heating block of the heating mold to a specified temperature.

[0055] The temperature measurement system includes a thermocouple, a temperature controller, a paperless recorder, etc. The thermocouples are embedded in the upper and lower heating blocks and connected to the paperless recorder through the temperature controller to detect the heating temperature rise curve of the heating mold and the heating temperature rise curve of the sheet metal;

[0056] The automatic lifting device 130 includes a high-temperature ejector mounted on an ejector mounting plate, which is fixed to nuts on two sets of linear lead screws. The lead screws are driven by two stepper motors to rotate, causing the nuts to rise, thereby pulling the ejector mounting plate upward. After the mold is opened, the ejector is driven by the stepper motor to automatically lift the sheet metal as the ejector mounting plate rises. This is used to lift the sheet metal after heating, facilitating subsequent transfer of the sheet metal.

[0057] In another embodiment, a loading device 200 for a replaceable mold includes a loading bracket 210, a replaceable mold 220, a pressure sensor, etc.; the loading bracket is equipped with a loading hydraulic cylinder, and the hydraulic cylinder connecting rod is equipped with a replaceable upper mold, which is pressed together with the replaceable lower mold by the downward pressure of the hydraulic cylinder, and the replaceable lower mold is connected to the pressure sensor to measure the pressure value; by replacing different molds, experiments are conducted on the different high-temperature properties of the sheet material.

[0058] In another embodiment, the clamping device 300 includes a clamping platform, a vertical vise and a tension sensor, etc.; the clamping platform is installed on the slide of the stretching system 400, and a slide rail slider device is installed on the platform. The vertical vise is installed on the slider, and the tension sensor is connected to one side of the vertical vise to measure the tension value applied to the vise; so that a section of the sheet material is clamped, the sheet material can be stretched, slid, transferred, etc.

[0059] In another embodiment, the stretching system 400 includes a slide, a linear motion mechanism 410 and a servo motor 420;

[0060] The linear motion mechanism 410 includes a speed reducer, a linear slide block, a gear rack, a frame, etc. The sheet material is passed through the linear structure, and the clamping device mounted on the linear slide block is clamped and bound to the linear mechanism. The sheet material can be dragged by the linear mechanism, and the speed of the servo motor is then controlled. The speed reducer, gear rack combination drives the clamping device to move linearly, and the sheet material can be dragged to move at a set speed for friction. The function is to enable the sheet material to slide or stretch at a certain speed, and to be transferred to a specified position, etc.

[0061] In another embodiment, the lubrication temperature measurement device 600 includes a lubrication system and an infrared temperature measurement system;

[0062] The lubrication system 610 includes a metal spray head and an integrated high-pressure air station (not shown) with hydraulic components. The spray head is mounted on a metal bracket and connected to the integrated high-pressure air station with hydraulic components via an air pipe. The compressed air is used to atomize the lubricating oil and spray it onto the surface of the sheet metal. This allows the degree of lubrication of the sheet metal by different high-temperature lubricants to be studied, that is, the sheet metal friction coefficient under different lubricants.

[0063] The infrared temperature measurement system 620 consists of an infrared temperature measurement probe, a transmitter and a paperless recorder. The infrared temperature measurement probe is installed on the same metal bracket, after the lubrication system and before the loading device. The probe is connected to the paperless recorder through the transmitter to collect the temperature curve of the sheet metal, which is used for spraying the sheet metal with forming lubricating oil and detecting the actual temperature before friction.

[0064] In another embodiment, the hydraulic loading system 500 includes hydraulic pressurization of a rapid heating device, hydraulic loading of a loading device for a replaceable mold, and an integrated hydraulic station containing hydraulic components. The hydraulic station is controlled by a PLC to accurately provide a set pressure to the rapid heating device, the loading device, etc.

[0065] In another embodiment, the PLC control system includes a hydraulic system control, a heating system control, a stretching system control, and a data acquisition system;

[0066] The control of the hydraulic system includes the heating pressure cylinder 510 providing a stable holding pressure to the contact-type rapid heating device, the loading pressure cylinder 520 consisting of two upper and lower friction heads, providing a stable and accurate loading pressure to the friction device, and controlling the holding time, pressing down and lifting of each pressure cylinder.

[0067] The control of the heating system includes a temperature controller controlling the heating rod through a solid-state relay so that the heating mold reaches a preset temperature and remains constant;

[0068] The control of the stretching system includes PLC controlling the servo electric cylinder to achieve a specified speed and a specified displacement stroke through a servo driver;

[0069] The data acquisition system includes the heating temperature rise curve of the heating block and the sheet material through the thermocouple, the actual temperature curve of the sheet material after lubrication collected by the infrared temperature measuring probe, and the actual force curve of the pressure and tension exerted on the sheet material collected by the pressure sensor and the tension sensor.

[0070] The test method of the multifunctional simulated sheet metal hot forming test device includes the following steps:

[0071] Step 1: Determine the type of experiment to be performed and install different molds in the loading device of the replaceable mold according to the needs, such as friction molds, U-shaped molds, cylindrical stretching molds, etc.

[0072] Step 2: Start the test, plug in the power, open the computer software, and reset and calibrate the initial position of the slide on the interface.

[0073] Step 3: Pass the sheet through the loading device of the replaceable mold. After determining the installation position of the sheet using the positioning plate on the contact rapid heating device, use the upper limit slot on the clamping device to determine the installation position of the other end of the sheet, and use a vertical vise to clamp the sheet.

[0074] Step 4: Open the software operation interface. Open different operation interfaces according to different experiments. For example, for friction experiments, input the test parameters, including heating mold temperature, heating and holding time, heating and holding pressure, loading pressure, and stretching sliding speed. These five parameters can be adjusted within a range.

[0075] Step 5: Start the equipment, the heating rod heats the heating mold to the corresponding temperature, and the temperature control system detects and maintains the temperature; then the hydraulic system pressurizes the sheet metal according to the specified heating and holding pressure, and after the preset holding time is reached, the mold is released, and then the automatic lifting device lifts the sheet metal;

[0076] Step 6: The movement sequence is different for different experiments. For the friction experiment, the hydraulic system pressurizes the friction die pair according to the specified loading and holding pressure, and finally starts the servo electric cylinder to pull the sheet metal for a unidirectional sliding friction test until the stroke ends. For the forming experiment, the stretching device is first started to transfer the heated sheet metal to the forming die. After positioning, the hydraulic system pressurizes the forming die pair according to the specified loading and holding pressure to form the sheet metal.

[0077] Step 7: Open the data acquisition interface. The data acquisition system can collect the heating curves of the heating block and the sheet through the thermocouple, the actual temperature curve of the sheet after lubrication through the infrared temperature probe, the actual force curve (Ft) of the tension on the sheet through the tension sensor, and the actual force curve (Pt) of the pressure on the sheet through the pressure sensor.

[0078] Step 8: After the test is completed, the loading hydraulic cylinder is lifted, the heating mold stops heating, the lifting device is reset, the fan is turned on for heat dissipation, the temperature drops to room temperature, the sheet metal is removed, and the equipment is turned off.

[0079] The above embodiments merely represent specific implementations of the present invention. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention.

Claims

1. A multifunctional simulated sheet metal hot forming test device is characterized by: The invention comprises a working and rapid heating device (100), a loading device (200) for a replaceable mold, a clamping device (300), a stretching system (400), a lubricating and temperature measuring device (600), a PLC control system, a data acquisition system, etc.; the rapid heating device, the lubricating and temperature measuring device (600), the loading device (200) for the replaceable mold, and the stretching system (400) are sequentially connected and installed on a workbench, the clamping device (300) is installed on a slide of the stretching system (400), the hydraulic system (500) provides accurate pressure to the device, and the entire device is controlled and supervised by a PLC control system.

2. A multifunctional simulated sheet metal hot forming test device as claimed in claim 1, characterized in that: The rapid heating device (100) includes a hydraulic support (110), a detachable sheet heating mold (120), a heating system, a temperature measuring system, and an automatic lifting device (130). The hydraulic support (110) comprises a mold mounting upper plate and a lower plate, a heating pressure cylinder mounting plate, a column, a linear bearing, etc. The detachable sheet heating mold (120) comprises an upper mold plate and a lower mold plate, upper and lower heating blocks, upper and lower pressure-resistant insulation plates, guide pillars and guide sleeves, limit pillars, positioning plates, insulation cotton, etc. The heating system includes a heating rod, a temperature controller, a solid-state relay, etc., which are used to heat the mold to a specified temperature; The temperature measurement system includes a thermocouple, a temperature controller, a paperless recorder, etc., which detects the temperature of the heating mold and the temperature of the sheet; The automatic lifting device (130) comprises a thimble, a thimble plate, a stepping motor, a screw rod set, etc., and is used to lift the sheet material after heating.

3. The multifunctional simulated sheet metal hot forming test device according to claim 1 is characterized in that: The loading device (200) of the replaceable mold comprises a loading bracket (210), a replaceable mold (220), a pressure sensor, etc. The loading bracket is equipped with a loading hydraulic cylinder, the hydraulic cylinder connecting rod is equipped with the replaceable upper mold, and the replaceable upper mold is pressed together with the replaceable lower mold by the downward pressure of the hydraulic cylinder. The replaceable lower mold is connected to the pressure sensor to measure the pressure value.

4. The multifunctional simulated sheet metal hot forming test device according to claim 1, characterized in that: The clamping device (300) includes a clamping platform, a vertical vise, and a tension sensor. The clamping platform is installed on a slide of the stretching system (400). A slide rail and slider device is installed on the platform. The vertical vise is installed on the slider. The tension sensor is connected to one side of the vertical vise to measure the tension value applied to the vise.

5. The multifunctional simulated sheet metal hot forming test device according to claim 1, characterized in that: A stretching system (400) includes a slide, a linear motion mechanism (410), and a servo motor (420); The linear motion mechanism (410) includes a reducer, a linear slide block, a gear rack, a frame, etc.

6. The multifunctional simulated sheet metal hot forming test device according to claim 1, characterized in that: A lubrication and temperature measurement device (600), comprising a lubrication system and an infrared temperature measurement system; The lubrication system (610) comprises a metal spray head, a solenoid valve, a pressure regulating filter and an oil tank. The spray head is mounted on a metal bracket and uses compressed air to atomize lubricating oil and spray it on the surface of the sheet material, which can simulate the process of spraying lubricating oil on the sheet material in actual production. The infrared temperature measurement system (620) consists of an infrared temperature measurement probe, a transmitter and a paperless recorder. The infrared temperature measurement probe is installed after the lubrication system and before the loading device of the replaceable mold, and is used to measure the temperature of the sheet metal after the lubricating oil is sprayed.

7. The multifunctional simulated sheet metal hot forming test device according to claim 1, characterized in that: The hydraulic loading system (500) includes hydraulic pressurization of a rapid heating device, hydraulic loading of a loading device for a replaceable mold, and a hydraulic station including a solenoid valve, a proportional valve, a pressure-maintaining valve, an oil tank, an explosion-proof motor, etc. The hydraulic station is controlled by a PLC to accurately provide a set pressure to the rapid heating device, the loading device, etc.

8. The multifunctional simulated sheet metal hot forming test device according to claim 1, characterized in that: The PLC control system includes the control of the hydraulic system, the control of the heating system, the control of the stretching system and the data acquisition system; The control of the hydraulic system includes the heating pressure cylinder (510) providing a stable holding pressure to the contact-type rapid heating device, the loading pressure cylinder (520) providing a stable and accurate loading pressure to the friction device, and controlling the holding time, pressing down, and lifting of each pressure cylinder. The control of the heating system includes a temperature controller controlling the heating rod through a solid-state relay so that the heating mold reaches a preset temperature and remains constant; The control of the stretching system includes PLC controlling the servo electric cylinder to achieve a specified speed and a specified displacement stroke through a servo driver; The data acquisition system includes the heating temperature rise curve of the heating block and the sheet material through the thermocouple, the actual temperature curve of the sheet material after lubrication collected by the infrared temperature measuring probe, and the actual force curve of the pressure and tension exerted on the sheet material collected by the pressure sensor and the tension sensor.

9. A test method using the multifunctional simulated sheet metal hot forming test device according to any one of claims 1 to 8, characterized in that: The steps include: Step 1: Determine the type of experiment to be performed and install different molds in the loading device of the replaceable mold according to the needs, such as friction molds, U-shaped molds, cylindrical stretching molds, etc. Step 2: Start the test, plug in the power, open the computer software, and reset and calibrate the initial position of the slide on the interface. Step 3: Pass the sheet through the loading device of the replaceable mold. After determining the installation position of the sheet using the positioning plate on the contact rapid heating device, use the upper limit slot on the clamping device to determine the installation position of the other end of the sheet, and use a vertical vise to clamp the sheet. Step 4: Open the software operation interface. Open different operation interfaces according to different experiments. For example, for friction experiments, input the test parameters, including heating mold temperature, heating and holding time, heating and holding pressure, loading pressure, and stretching sliding speed. These five parameters can be adjusted within a range. Step 5: Start the equipment, the heating rod heats the heating mold to the corresponding temperature, and the temperature control system detects and maintains the temperature; then the hydraulic system pressurizes the sheet metal according to the specified heating and holding pressure, and after the preset holding time is reached, the mold is released, and then the automatic lifting device lifts the sheet metal; Step 6: The movement sequence is different for different experiments. For the friction experiment, the hydraulic system pressurizes the friction die pair according to the specified loading and holding pressure, and finally starts the servo electric cylinder to pull the sheet metal for a unidirectional sliding friction test until the stroke ends. For the forming experiment, the stretching device is first started to transfer the heated sheet metal to the forming die. After positioning, the hydraulic system pressurizes the forming die pair according to the specified loading and holding pressure to form the sheet metal. Step 7: Open the data acquisition interface. The data acquisition system can collect the heating curves of the heating block and the sheet through the thermocouple, the actual temperature curve of the sheet after lubrication through the infrared temperature probe, the actual force curve (Ft) of the tension on the sheet through the tension sensor, and the actual force curve (Pt) of the pressure on the sheet through the pressure sensor. Step 8: After the test is completed, the loading hydraulic cylinder is lifted, the heating mold stops heating, the lifting device is reset, the fan is turned on for heat dissipation, the temperature drops to room temperature, the sheet metal is removed, and the equipment is turned off.

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