Super martensitic stainless steel heat treatment vacuum furnace for automobile fasteners

Abstract

The invention relates to the technical field of heat treatment equipment, in particular to a super martensitic stainless steel heat treatment vacuum furnace for automobile fasteners, which comprises a furnace body, a rotating column is vertically and rotatably mounted in the furnace body, a driving motor is fixedly mounted at the upper end of the furnace body, and a placing disc is fixedly mounted on the rotating column. A placing disc is arranged in the furnace body, a plurality of rotating holes are formed in the placing disc, rotating shafts are vertically and rotatably mounted in the rotating holes, rotating discs are fixedly mounted at the upper ends of the rotating shafts, a clamping assembly is arranged on a rotating column, and a rotating assembly is arranged in the furnace body. The rotating column and the driving motor can drive the fastener to rotate in the furnace body, and meanwhile, the rotating shaft and the rotating assembly are matched to drive the fastener to rotate, so that the fastener receives heat radiation uniformly in all directions, performance difference caused by uneven local heating is avoided, stress balance of all parts is guaranteed, and the service life of the fastener is prolonged. And the quality and the reliability of the fastener are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of heat treatment equipment, and in particular to a vacuum furnace for heat treating super martensitic stainless steel for automotive fasteners. Background Art

[0002] Automotive fasteners are crucial for the safe and stable operation of automobiles. Super martensitic stainless steel is widely used in the manufacture of automotive fasteners due to its good strength, toughness, and corrosion resistance. However, its heat treatment process has a crucial impact on performance, especially the precise control of the heating and cooling processes.

[0003] When the existing heat treatment vacuum furnace processes super martensitic stainless steel for automotive fasteners, the heating uniformity is poor. For fasteners in the same batch, different parts will be in different temperature fields, resulting in performance differences in different parts due to uneven heating, causing uneven stress distribution in each part and affecting the product quality and reliability. Summary of the Invention

[0004] The purpose of the present invention is to solve the following disadvantages in the prior art: when the existing heat treatment vacuum furnace processes super martensitic stainless steel for automotive fasteners, the heating uniformity is poor. For fasteners in the same batch, different parts will be in different temperature fields, resulting in performance differences in different parts due to uneven heating, causing uneven stress distribution in each part and affecting the product quality and reliability. Thus, a vacuum furnace for heat treating super martensitic stainless steel for automotive fasteners is proposed.

[0005] In order to achieve the above purpose, the present invention adopts the following technical scheme: A vacuum furnace for heat treating super martensitic stainless steel for automotive fasteners, including a furnace body and a furnace door rotatably installed on the furnace body. A plurality of heating modules are equidistantly installed on the inner circumference of the furnace body, and a vacuum pump is fixedly installed on the furnace body. A rotating column is vertically rotatably installed in the furnace body, a driving motor is fixedly installed at the upper end of the furnace body, the upper end of the rotating column passes through the furnace body and is fixedly connected to the output end of the driving motor. A placing plate is fixedly installed on the rotating column, a plurality of rotating holes are opened on the placing plate, and a rotating shaft is vertically rotatably installed in each of the plurality of rotating holes. A rotating disk is fixedly installed at the upper end of each of the plurality of rotating shafts. A plurality of clamping assemblies for clamping fasteners are provided on the rotating column, and a rotating assembly for simultaneously driving a plurality of rotating shafts to rotate is provided in the furnace body.

[0006] As a preferred solution, the clamping assembly includes a bracket horizontally fixedly installed on the rotating column, a threaded rod, an adjusting block fixedly installed at the upper end of the threaded rod, and a positioning disk rotatably installed at the lower end of the threaded rod. A threaded hole is opened on the bracket, and the threaded rod is vertically threadedly inserted into the threaded hole. The positioning disk is located directly above the rotating disk.

[0007] As a preferred solution, the rotating assembly includes a main gear fixedly installed in the furnace body through a support rod and a plurality of driven gears respectively fixedly installed at the lower ends of a plurality of rotating shafts, and the plurality of driven gears are all meshed and connected with the main gear.

[0008] As a preferred solution, a plurality of mounting plates are vertically and fixedly installed in the furnace body, the heating module is fixedly installed on the mounting plates, the heating module is composed of a heating element and a temperature sensor, and the heating element is a high-performance resistance wire.

[0009] As a preferred solution, a reflector is fixedly installed on the mounting plate, the reflector is arranged in a horn shape, and the heating element is installed in the reflector.

[0010] As a preferred solution, cooling openings are symmetrically formed in the side surface of the furnace body, rectangular covers are fixedly installed on both of the two cooling openings, a moving plate is horizontally and slidably installed in the rectangular cover through a sliding assembly, a cooling assembly for cooling fasteners is arranged on the moving plate, moving openings are formed at both the upper and lower ends of the moving plate, slide rails are horizontally and slidably installed in both of the two moving openings, the two slide rails are horizontally and fixedly installed on the inner sides of the upper and lower parts of the rectangular cover, a mounting hole is formed in the moving plate, the cold air assembly includes a storage tank fixedly installed on the furnace body, a pressure pump fixedly installed at the lower end of the storage tank, a conveying pipeline installed at one end of the pressure pump, and a jetting component for jetting cooling gas arranged in the mounting hole, and the jetting component is installed in the mounting hole.

[0011] As a preferred solution, the jetting component includes a rectangular plate fixedly installed in the mounting hole and a plurality of gas nozzles installed on the side surface of the rectangular plate, a cavity is formed inside the rectangular plate, the plurality of gas nozzles are all communicated with the cavity, and the end of the conveying pipeline away from the pressure pump is fixedly connected with the rectangular plate and communicated with the cavity.

[0012] As a preferred solution, partition plates are symmetrically and rotatably installed at the positions of the cooling openings inside the furnace body, and a transmission assembly for driving the two partition plates to rotate simultaneously is arranged on the moving plate.

[0013] As a preferred solution, the transmission assembly includes a top rod horizontally and fixedly installed on the side surface of the moving plate and two support rods rotatably installed at one end of the top rod, and the ends of the two support rods away from the top rod are respectively hinged to the two partition plates.

[0014] As a preferred solution, magnetic blocks are symmetrically fixedly installed on the side of the moving plate away from the furnace body, metal blocks are symmetrically fixedly installed at one end of the rectangular cover, and the two metal blocks are respectively magnetically connected with the two magnetic blocks.

[0015] Compared with the prior art, the beneficial effects of the present invention are: 1. The automotive fasteners are clamped and fixed on the rotating disk by the clamping assembly. When heated by the heating module, the rotating column and the driving motor can drive the fasteners to rotate in the furnace body. At the same time, through the mutual cooperation of the rotating shaft and the rotating assembly, the fasteners are driven to rotate self, so that the fasteners can receive thermal radiation evenly in all directions, avoiding performance differences caused by uneven local heating, ensuring balanced stress in all parts, and effectively improving the quality and reliability of the fasteners.

[0016] 2. The reflector can efficiently reflect the radiant heat generated by the heating element to the central area of the furnace, reduce the heat dissipation to the furnace wall, accelerate the heating speed of the workpiece, and improve the heating uniformity at the same time.

[0017] 3. After the heat preservation of the fasteners is completed, nitrogen can be sprayed on the fasteners in the furnace body through the mutual cooperation of the moving plate, the storage tank, the pressure pump, the conveying pipeline and the jet component for cooling treatment to ensure that the fasteners obtain the ideal martensite structure and performance.

[0018] 4. When the temperature of the furnace body rises, the partition plate is in a closed state. The partition plate can effectively block the heat of the furnace body from entering the rectangular cover, avoiding too high temperature, affecting the use of the jet component and the later cooling effect.

[0019] 5. The vacuum pump can extract the air in the furnace body to keep the furnace body in a vacuum state. The stable vacuum environment effectively prevents the oxidation and decarburization of the fasteners and ensures the corrosion resistance and service life of the automotive fasteners. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a three-dimensional structural schematic diagram of a supermartensitic stainless steel heat treatment vacuum furnace for automotive fasteners proposed by the present invention; Figure 2 is a three-dimensional structural schematic diagram of the inner side of the furnace body; Figure 3 is a three-dimensional structural schematic diagram of the furnace body, the rectangular cover and the cooling assembly; Figure 4 is a three-dimensional structural schematic diagram of the rotating column, the placing disk, the rotating shaft, the rotating disk, the clamping assembly and the transmission assembly; Figure 5 is a three-dimensional structural schematic diagram of the heating module; Figure 6 is a three-dimensional structural schematic diagram of the rectangular cover, the moving plate, the rectangular plate and the partition plate; Figure 7 is Figure 6 the enlarged structural schematic diagram at A in Figure 8 is Figure 6 the enlarged structural schematic diagram at B in Figure 9Schematic diagram of the three-dimensional partial cross-sectional structure of the moving plate, rectangular plate and gas nozzle.

[0021] In the figure: 1 furnace body, 2 furnace door, 3 heating module, 4 vacuum pump, 5 rotating column, 6 drive motor, 7 placement plate, 8 rotating shaft, 9 rotating disk, 10 bracket, 11 threaded rod, 12 adjusting block, 13 positioning disk, 14 support rod, 15 main gear, 16 driven gear, 17 mounting plate, 18 reflector, 19 rectangular cover, 20 moving plate, 21 slide rail, 22 storage tank, 23 pressure pump, 24 rectangular plate, 25 gas nozzle, 26 partition plate, 27 ejector rod, 28 support rod, 29 magnetic block, 30 metal block, 31 conveying pipeline, 301 heating element, 302 temperature sensor. Specific implementation mode

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0023] Refer to Figures 1-9 , a super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners, including a furnace body 1 and a furnace door 2 rotatably installed on the furnace body 1. A plurality of groups of heating modules 3 are installed equidistantly on the inner circumference of the furnace body 1. A vacuum pump 4 is fixedly installed on the furnace body 1. The heating module 3 can increase the temperature inside the furnace body 1, and the vacuum pump 4 can extract the air inside the furnace body 1 to keep the furnace body 1 in a vacuum state. The furnace door 2 is tightly connected to the furnace body 1 by means of a sealing strip to ensure a stable vacuum environment inside the furnace. The stable vacuum environment effectively prevents the oxidation and decarburization of the fasteners and ensures the corrosion resistance and service life of the automotive fasteners.

[0024] A rotating column 5 is vertically rotatably installed inside the furnace body 1. A drive motor 6 is fixedly installed at the upper end of the furnace body 1. The upper end of the rotating column 5 passes through the furnace body 1 and is fixedly connected to the output end of the drive motor 6. A placement plate 7 is fixedly installed on the rotating column 5. A plurality of rotating holes are opened on the placement plate 7. A rotating shaft 8 is vertically rotatably installed in each of the plurality of rotating holes. A rotating disk 9 is fixedly installed at the upper end of each of the plurality of rotating shafts 8. A plurality of clamping assemblies for clamping fasteners are provided on the rotating column 5. A rotating assembly for simultaneously driving a plurality of rotating shafts 8 to rotate is provided inside the furnace body 1.

[0025] The rotating column 5 is rotatably installed in the middle part of the furnace body 1. A plurality of heating modules 3 are arranged around the rotating column 5. Before heat treatment of automotive fasteners, the fasteners are placed on the rotating disc 9, and then the fasteners are clamped and fixed on the rotating disc 9 by the clamping assembly. By driving the driving motor 6, the rotating column 5 can be driven to rotate. When the rotating column 5 rotates, it will drive a plurality of rotating discs 9 to rotate around the rotating column 5 through the placing disc 7. At the same time, a plurality of rotating shafts 8 can be driven to rotate simultaneously through the rotating assembly. When the rotating shafts 8 rotate, they will drive the fasteners to rotate around themselves through the rotating discs 9, so that the fasteners can uniformly receive heat radiation in all directions, avoiding performance differences caused by uneven local heating, ensuring balanced stress in each part, and effectively improving the quality and reliability of the fasteners.

[0026] The clamping assembly includes a bracket 10 horizontally and fixedly installed on the rotating column 5, a threaded rod 11, an adjusting block 12 fixedly installed at the upper end of the threaded rod 11, and a positioning disc 13 rotatably installed at the lower end of the threaded rod 11. A threaded hole is formed in the bracket 10, and the threaded rod 11 is vertically threadedly inserted into the threaded hole. The positioning disc 13 is located directly above the rotating disc 9. When fixing the fasteners, the fasteners are placed on the rotating disc 9, and then the adjusting block 12 is rotated to drive the threaded rod 11 to rotate. Under the action of the bracket 10, the threaded rod 11 drives the positioning disc 13 to move towards the rotating disc 9 until the positioning disc 13 contacts the fasteners, thereby clamping and fixing the fasteners between the rotating disc 9 and the positioning disc 13.

[0027] The rotating assembly includes a main gear 15 fixedly installed in the furnace body 1 through a support rod 14 and a plurality of driven gears 16 respectively fixedly installed at the lower ends of a plurality of rotating shafts 8. A plurality of driven gears 16 are all meshed with the main gear 15. When the rotating column 5 drives the placing disc 7 to rotate, it will drive a plurality of rotating shafts 8 to rotate around the rotating column 5, and at the same time drive a plurality of driven gears 16 to rotate around the main gear 15. Since the driven gears 16 are meshed with the main gear 15, the rotating shafts 8 will be driven to rotate on the placing disc 7 through the driven gears 16, and then the fasteners will be driven to rotate around themselves through the rotating discs 9.

[0028] A plurality of mounting plates 17 are vertically and fixedly installed in the furnace body 1, and the heating modules 3 are fixedly installed on the mounting plates 17. The heating module 3 is composed of a heating element 301 and a temperature sensor 302. The heating element 301 is a high-performance resistance wire. Both the heating element 301 and the temperature sensor 302 in the heating module 3 are controlled by the control system of the furnace body 1. The temperature sensor 302 monitors the temperature in real time and feeds it back to the control system. The control system accurately regulates the power of each module according to the preset heating curve to ensure that the temperature in the furnace rises evenly.

[0029] A reflector 18 is fixedly installed on the mounting plate 17. The reflector 18 is arranged in a horn shape. The heating element 301 is installed inside the reflector 18. The reflector 18 is made of a metal material with a high reflectivity, and its shape is carefully designed to efficiently reflect the radiant heat generated by the heating element 301 to the central area of the furnace, reduce the heat dissipation to the furnace wall, accelerate the workpiece heating rate, and improve the heating uniformity at the same time.

[0030] Cooling openings are symmetrically formed on one side of the furnace body 1. Rectangular covers 19 are fixedly installed on both of the two cooling openings. A moving plate 20 is horizontally slidably installed in the rectangular cover 19 through a sliding assembly. Moving openings are formed at both the upper and lower ends of the moving plate 20. Slide rails 21 are horizontally slidably installed in both of the two moving openings. The two slide rails 21 are horizontally fixedly installed on the upper and lower inner sides of the rectangular cover 19. A cooling assembly for cooling the fasteners is provided on the moving plate 20. An installation hole is formed in the moving plate 20. The cold air assembly includes a storage tank 22 fixedly installed on the furnace body 1, a pressure pump 23 fixedly installed at the lower end of the storage tank 22, a conveying pipeline 31 installed at one end of the pressure pump 23, and a jet component for jetting cooling gas arranged in the installation hole. The jet component is installed in the installation hole. The jet component includes a rectangular plate 24 fixedly installed in the installation hole and a plurality of gas nozzles 25 installed on the side surface of the rectangular plate 24. A cavity is formed inside the rectangular plate 24. The plurality of gas nozzles 25 are all communicated with the cavity. The end of the conveying pipeline 31 away from the pressure pump 23 is fixedly connected to the rectangular plate 24 and is communicated with the cavity.

[0031] When the temperature in the furnace reaches the preset heat preservation temperature, the control system keeps the power of the heating system unchanged, so that the fasteners are heat-preserved at this temperature for a certain period of time to ensure the tissue homogenization.

[0032] The storage tank 22 is filled with nitrogen. The moving plate 20 horizontally slides in the rectangular cover 19 through the two slide rails 21. The cavity formed in the rectangular plate 24 is communicated with the storage tank 22 through the conveying pipeline 31.

[0033] After the heat preservation is completed, move the moving plate 20 to move the plurality of gas nozzles 25 installed on the rectangular plate 24 towards the cooling opening direction, and then start the pressure pump 23 to convey the nitrogen in the storage tank 22 to the cavity through the conveying pipeline 31, and then spray it out through the plurality of gas nozzles 25 and enter the furnace body 1 through the cooling opening. During the rotation of the fasteners, the nitrogen is evenly sprayed on the fasteners to ensure that the fasteners obtain an ideal martensite structure and performance.

[0034] Inside the furnace body 1, partition plates 26 are symmetrically and rotatably installed at the cooling openings. A transmission assembly for driving the two partition plates 26 to rotate simultaneously is provided on the moving plate 20. The transmission assembly includes a push rod 27 horizontally and fixedly installed on the side of the moving plate 20 and two support rods 28 both rotatably installed at one end of the push rod 27. The ends of the two support rods 28 far from the push rod 27 are respectively hinged to the two partition plates 26.

[0035] The partition plates 26 are made of high-temperature resistant and high heat-resistant materials. The two partition plates 26 are rotatably installed at the cooling openings. During the heating process of the fasteners, the partition plates 26 are in a closed state, thus blocking the cooling openings. The gas nozzles 25 are isolated within the rectangular cover 19 through the partition plates 26. The partition plates 26 can effectively block the heat in the furnace body 1 from entering the rectangular cover 19, avoiding excessive temperature and affecting the use of the jet components and the subsequent cooling effect.

[0036] On the side of the moving plate 20 far from the furnace body 1, magnetic blocks 29 are symmetrically and fixedly installed. At one end of the rectangular cover 19, metal blocks 30 are symmetrically and fixedly installed. The two metal blocks 30 are respectively magnetically connected to the two magnetic blocks 29. When the two partition plates 26 are in a closed state, the two metal blocks 30 just come into contact with the two magnetic blocks 29 on the moving plate 20. Under the action of magnetic force, the movement of the moving plate 20 is avoided, thus ensuring that the cooling holes are in a closed state.

[0037] When cooling is required, a thrust is applied to the moving plate 20 to overcome the magnetic force between the magnetic blocks 29 and the metal blocks 30, thereby driving the moving plate 20 to move towards the cooling opening. At the same time, the push rod 27 installed on the rectangular plate 24 will drive the two partition plates 26 to rotate through the two support rods 28, thus opening the cooling holes, realizing the automatic rotation of the partition plates 26, and making the operation more convenient.

[0038] In the present invention, the rotating column 5 is rotatably installed in the middle part of the furnace body 1. Multiple groups of heating modules 3 are arranged around the rotating column 5. Before the heat treatment of automotive fasteners, the fasteners are placed on the rotating disk 9, and then the fasteners are clamped and fixed on the rotating disk 9 through the clamping assembly. By driving the driving motor 6, the rotating column 5 can be driven to rotate. When the rotating column 5 rotates, it will drive multiple rotating disks 9 to rotate around the rotating column 5 through the placing disk 7. At the same time, the rotating assembly can drive multiple rotating shafts 8 to rotate simultaneously. While rotating, the rotating shafts 8 will drive the fasteners to rotate around themselves through the rotating disks 9, enabling the fasteners to uniformly receive heat radiation in all directions, avoiding performance differences caused by uneven local heating, ensuring stress balance in each part, and effectively improving the quality and reliability of the fasteners.

[0039] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, making equivalent replacements or changes, should be covered within the protection scope of the present invention.

Claims

1. A super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners, comprising a furnace body (1) and a furnace door (2) rotatably mounted on the furnace body (1), characterized in that: A plurality of groups of heating modules (3) are equidistantly mounted on the inner circumference of the furnace body (1); a vacuum pump (4) is fixedly mounted on the furnace body (1); a rotating column (5) is vertically rotatably mounted in the furnace body (1); a driving motor (6) is fixedly mounted on the upper end of the furnace body (1); the upper end of the rotating column (5) passes through the furnace body (1) and is fixedly connected to the output end of the driving motor (6); a placement plate (7) is fixedly mounted on the rotating column (5); a plurality of rotating holes are provided on the placement plate (7); a plurality of rotating holes are vertically rotatably mounted with rotating shafts (8); a plurality of rotating shafts (8) are fixedly mounted with rotating disks (9) at their upper ends; a plurality of groups of clamping components for clamping fasteners are provided on the rotating column (5); and a rotating component for simultaneously driving the plurality of rotating shafts (8) to rotate is provided in the furnace body (1).

2. The super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners according to claim 1, characterized in that: The clamping assembly comprises a bracket (10) fixedly mounted horizontally on a rotating column (5), a threaded rod (11), an adjustment block (12) fixedly mounted on the upper end of the threaded rod (11), and a positioning plate (13) rotatably mounted on the lower end of the threaded rod (11); a threaded hole is provided on the bracket (10), the threaded rod (11) is vertically threadedly inserted into the threaded hole, and the positioning plate (13) is located directly above the rotating plate (9).

3. The super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners according to claim 1, characterized in that: The rotating assembly comprises a main gear (15) fixedly mounted in the furnace body (1) via a support rod (14) and a plurality of slave gears (16) respectively fixedly mounted on the lower ends of a plurality of rotating shafts (8), wherein the plurality of slave gears (16) are all meshedly connected with the main gear (15).

4. The super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners according to claim 1, characterized in that: A plurality of mounting plates (17) are vertically fixedly installed in the furnace body (1), the heating module (3) is fixedly installed on the mounting plate (17), the heating module (3) is composed of a heating element (301) and a temperature sensor (302), and the heating element (301) is a high-performance resistance wire.

5. The super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners according to claim 4, characterized in that: A reflective cover (18) is fixedly mounted on the mounting plate (17); the reflective cover (18) is arranged in a trumpet shape; and the heating element (301) is mounted inside the reflective cover (18).

6. The super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners according to claim 1, characterized in that: The furnace body (1) is symmetrically provided with cooling openings on the side, and a rectangular cover (19) is fixedly installed on the two cooling openings. A movable plate (20) is horizontally slidably installed in the rectangular cover (19) through a sliding assembly. A cooling assembly for cooling the fastener is provided on the movable plate (20). The movable plate (20) is provided with movable openings at both upper and lower ends, and slide rails (21) are horizontally slidably installed in the two movable openings. The two slide rails (21) are horizontally fixedly installed on the upper and lower inner sides of the rectangular cover (19). A mounting hole is provided on the movable plate (20). The cold air assembly comprises a storage tank (22) fixedly installed on the furnace body (1), a pressure pump (23) fixedly installed at the lower end of the storage tank (22), a delivery pipe (31) installed at one end of the pressure pump (23), and an injection component arranged in the installation hole for ejecting cooling gas. The injection component is installed in the installation hole.

7. The super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners according to claim 6, characterized in that: The jetting component comprises a rectangular plate (24) fixedly mounted in the mounting hole and a plurality of gas nozzles (25) mounted on the side of the rectangular plate (24); a cavity is provided inside the rectangular plate (24); the plurality of gas nozzles (25) are all connected to the cavity; and an end of the delivery pipe (31) away from the pressure pump (23) is fixedly connected to the rectangular plate (24) and is connected to the cavity.

8. The super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners according to claim 7, characterized in that: A partition plate (26) is symmetrically rotatably mounted inside the furnace body (1) at the cooling port, and a transmission assembly for driving the two partition plates (26) to rotate simultaneously is provided on the movable plate (20).

9. The super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners according to claim 6, characterized in that: The transmission assembly comprises a top rod (27) fixedly mounted horizontally on the side of the moving plate (20) and two support rods (28) rotatably mounted on one end of the top rod (27), and the ends of the two support rods (28) away from the top rod (27) are respectively hinged to the two partitions (26).

10. The super martensitic stainless steel heat treatment vacuum furnace for automotive fasteners according to claim 6, characterized in that: A magnetic block (29) is symmetrically fixedly mounted on one side of the movable plate (20) away from the furnace body (1), and a metal block (30) is symmetrically fixedly mounted on one end of the rectangular cover (19), and the two metal blocks (30) are magnetically connected to the two magnetic blocks (29) respectively.

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