Tension detection equipment for isothermal quenching nodular cast iron material and use method of tension detection equipment

Abstract

The invention belongs to the technical field of tensile testing, and particularly relates to tensile force detection equipment for an isothermal quenching nodular cast iron material and a using method thereof.The tensile force detection equipment comprises a thermal expansion type fastening clamping mechanism, a manual clamping and releasing assembly, an environment simulation mechanism and a rack assembly, and the rack assembly comprises a bottom plate, a frame type rack and a top plate; the frame type rack is arranged on the bottom plate, and the top plate is arranged on the frame type rack. The environment simulation mechanism is provided for the first time, and lifting avoidance of the induction heating assembly can be completed through stretching and retracting of the telescopic cylinder under the condition that an active driving device of the induction heating assembly is not designed; moreover, by utilizing the characteristic that the thermal expansion coefficients of a metal material and a silicon nitride ceramic material are different, the clamping slide block is automatically locked and unlocked on the workpiece to be tested by utilizing the heat during environment simulation, so that the structural design is simplified, and the operation control steps are reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of tensile testing, and specifically refers to a tensile testing device for isothermal quenching ductile iron material and a use method thereof. Background Art

[0002] Austempered ductile iron (ADI) has the advantages of low cost, good high-temperature stability, and high comprehensive performance. It is widely used in various high-temperature and high-corrosive working scenarios. For example, many parts in the engine will use austempered ductile iron. In the prior art, in order to evaluate the tensile properties of a material at high temperature, it is generally necessary to first test the tensile properties of the material at room temperature, and then correct the performance attenuation caused by high temperature through theoretical calculation, but the range of this correction value is relatively large. Taking austempered ductile iron (ADI) as an example, at an operating temperature of about 200 degrees, compared with room temperature, it is generally believed that the tensile performance is attenuated by 15%-25%, but such a large error range is unacceptable in many scenarios. Therefore, the most accurate way is to simulate the high-temperature environment in which the parts work normally, and perform a tensile test on the material sample at this temperature.

[0003] In addition, the traditional tensile testing device clamps the two ends of the specimen through a rotating locking fixture similar to a three-jaw chuck. If it is locked manually, the locking torque must be controlled more accurately. If it is too low, the locking will be loose, and if it is too high, it will cause damage to the specimen. Even when locked, the thermal expansion characteristics of the metal may cause the parts to loosen (when the metal ring parts are heated, the inner and outer diameters will increase). If it is locked automatically by a motor, the complexity of the structure will be greatly increased. In addition, whether the motor can work at high temperatures is also a problem that must be faced. Summary of the invention

[0004] In view of the above situation, in order to overcome the defects of the prior art, the present invention proposes a tension testing device for isothermal quenching ductile iron material and a method for using the same; on the one hand, the present invention first proposes an environmental simulation mechanism, which improves the accuracy of the test by simulating the working temperature, and at the same time, through the structural design of the lifting component and the top locking component, the induction heating component can be lifted and lowered by the extension and retraction of the telescopic cylinder without designing an active driving device for the induction heating component; Moreover, the present invention also creatively proposes a thermal expansion type fastening clamping mechanism, which utilizes the different thermal expansion coefficients of metal materials and silicon nitride ceramic materials and utilizes the heat during environmental simulation to automatically complete the locking and unlocking of the clamping slider on the workpiece to be tested, thereby simplifying the structural design and reducing the steps of operation control.

[0005] The technical solution adopted by the present invention is as follows: The present invention proposes a tensile testing device for isothermal quenching ductile iron materials, including a thermal expansion type fastening and clamping mechanism, a manual clamping and releasing component, an environmental simulation mechanism and a frame component, the frame component includes a bottom plate, a frame frame and a top plate, the frame frame is arranged on the bottom plate, and the top plate is arranged on the frame frame; the thermal expansion type fastening and clamping mechanism is arranged on the manual clamping and releasing component, the manual clamping and releasing component is arranged on the frame component and the environmental simulation mechanism, and the environmental simulation mechanism is arranged on the frame component.

[0006] Furthermore, the thermal expansion type fastening clamping mechanism includes a clamping shell component, a thermal expansion type anti-detachment fastening component and a rebound shrinkage clamping component. The clamping shell component is arranged on the manual clamping release component, the thermal expansion type anti-detachment fastening component is arranged in the clamping shell component, and the rebound shrinkage clamping component is arranged on the thermal expansion type anti-detachment fastening component.

[0007] The thermal expansion fastening clamping mechanism uses the heat inherent in the environmental simulation process, combined with the thermal expansion and contraction characteristics of the metal during heating, to automatically switch between the pre-clamping mode and the stable clamping mode. On the one hand, it can reduce the moving parts and steps required for manual operation or automatic locking, and reduce the complexity of the structure; on the other hand, compared with the traditional threaded tightening method, it can also reduce the wear rate of parts.

[0008] Among them, the thermal expansion type fastening clamping mechanism and the manual clamping and releasing assembly are symmetrically arranged in two groups, the clamping shell assembly includes a clamping base and a clamping sleeve, the clamping base is arranged on the manual clamping and releasing assembly, and the clamping sleeve is arranged on the clamping base.

[0009] Preferably, the thermal expansion anti-slip fastening assembly includes a sliding baffle, a clamping slider and an inner conical cone. The sliding baffle is snap-fitted and slidably arranged in the clamping sleeve. The sliding baffle is provided with sliding grooves evenly distributed in an annular shape. The clamping slider is provided with a sliding portion, and the sliding portion is snap-fitted and slidably arranged in the sliding groove. The outer conical surface of the clamping slider is provided with arc-shaped convex patterns in an array. The inner conical cone is fixedly connected to the inside of the clamping sleeve, and the inner conical surface of the inner conical cone is provided with annular grooves matching the arc-shaped convex patterns in an array.

[0010] Through the combination of the arc-shaped convex pattern and the annular groove, the clamping slider can form an interference fit with the inner conical cone after expansion, without longitudinal relative sliding due to the increase of the extrusion pressure between the two, thereby avoiding the impact on the clamping tightness during the increase of the extrusion pressure.

[0011] The two ends of the workpiece to be measured are clamped by a clamping slider; the clamping slider is made of a metal material that expands after being heated, and the inner conical frustum is made of Si3N4 silicon nitride ceramic material.

[0012] The clamping slider has a more obvious thermal expansion phenomenon after being heated, while the thermal expansion coefficient of the inner conical cone is much smaller. Therefore, when the ambient temperature increases, the clamping slider and the inner conical cone can be transformed from the original clearance fit to the interference fit, thereby achieving stable clamping of the workpiece to be measured; and after the temperature drops, the clamping slider and the inner conical cone can return to the clearance fit state; replacing the traditional mechanical locking mechanism with thermal expansion omits a large number of transmission mechanisms and simplifies the manual operation steps.

[0013] As a further preferred embodiment of the present invention, a polygonal boss is also provided at the center position of the sliding baffle, and the number of sides of the polygonal boss is equal to the number of sliding grooves. The rebound and contraction clamping assembly includes a synchronization dial and a support spring. The support spring is arranged between the side of the polygonal boss and the sliding portion. The synchronization dial is rotatably arranged on the sliding baffle, and the synchronization dial and the sliding baffle are connected by a torsion spring. The inner ring of the synchronization dial is evenly distributed with arc-shaped portions matching the sliding portion. Under the elastic force of the torsion spring, the synchronization dial has the function of pushing the clamping slider to synchronously contract through its own rotation.

[0014] Under the elastic force of the torsion spring, the synchronous dial always has a tendency to push the clamping slider inward. Through the supporting spring, each clamping slider can be tightly attached to the arc portion, thereby achieving the technical effect of synchronously controlling the contraction of the clamping slider.

[0015] Furthermore, the manual clamping release assembly includes a separation ring, a release lever, a fork, a micro-groove positioning spring and a mounting seat, the separation ring is fixedly connected to the clamping base, the release lever is arranged on the polygonal boss, the release lever is slidably arranged in the clamping base, the end of the release lever is provided with a lever boss, the fork is rotatably arranged on the outside of the clamping base, the micro-groove positioning spring is arranged between the clamping base and the polygonal boss, one of the mounting seats is arranged on the bottom plate, the other of the mounting seats is arranged on the lifting assembly, and the clamping base is arranged on the mounting seat.

[0016] By pressing the shift fork, each clamping slide block can be actively separated, thereby avoiding the phenomenon of local deformation and difficulty in removal caused by excessive squeezing force of the clamping slide block on the workpiece to be measured.

[0017] Furthermore, the environmental simulation mechanism includes an induction heating component, a lifting component and a top locking component, the induction heating component is slidably engaged on the lifting component, the lifting component is arranged on the top plate, and the top locking component is evenly distributed in a ring shape on the outside of the induction heating component.

[0018] Preferably, the lifting assembly comprises a telescopic cylinder, a vertical guide rod and an inner stop block, the telescopic cylinder is arranged on the top plate, the vertical guide rod is arranged on the top plate, and the inner stop block is arranged on the induction heating assembly.

[0019] As a further preferred embodiment of the present invention, the induction heating assembly includes a heat exchange sleeve, an upper thermal insulation layer and an induction coil. The outer ring of the heat exchange sleeve is evenly distributed with guide sleeves. The heat exchange sleeve is slidably mounted on the vertical guide rod through the engagement of the guide sleeves. The upper thermal insulation layer is arranged at the top of the heat exchange sleeve. The induction coil is arranged inside the heat exchange sleeve. The inner stopper is fixedly connected to the inner wall of the heat exchange sleeve.

[0020] The induction coil can heat the environment of the workpiece to be tested by induction heating, thereby simulating the working temperature of the workpiece to be tested. The heat exchange sleeve has the function of heat insulation during the heating process, and can be quickly cooled by the flow of internal medium during the cooling process.

[0021] Wherein, the top locking assembly includes an outer stopper, the outer stopper is fixed to the top end of the outer wall of the heat exchange sleeve, and the height of the inner stopper is lower than that of the outer stopper; a tension sensor is provided at the end of the telescopic cylinder.

[0022] The induction heating component can be pushed to the top by the retraction of the telescopic cylinder and maintained in position by the top locking component. When the fixation is completed and testing is required, it is only necessary to energize the electromagnet, and the induction heating component will fall under the action of its own weight and cover the workpiece to be tested inside itself.

[0023] Preferably, the top locking assembly also includes a telescopic bracket, a telescopic lock tongue, a lock tongue return spring and an electromagnet, the telescopic bracket is arranged on the top plate, the telescopic lock tongue is slidably arranged in the telescopic bracket, an armature is provided at the tail of the telescopic lock tongue, the lock tongue return spring is arranged between the telescopic lock tongue and the telescopic bracket, the electromagnet is arranged on the top plate, and the positions of the electromagnet and the armature correspond to each other.

[0024] The springs in the present solution all have high temperature resistance characteristics and will not have a significant impact on the compression rebound performance at the working temperature of the present invention.

[0025] The present invention also proposes a method for using a tensile force detection device for isothermal quenching ductile iron material, which specifically comprises the following steps: Step 1: Before clamping the workpiece to be tested, the induction heating component is fixed at the top by the top locking component, and then the two ends of the workpiece to be tested are clamped and fixed in turn, first clamping and fixing the lower end of the workpiece to be tested; Press the end of the shift fork toward the clamping base. When the shift fork pulls out the release lever, the sliding baffle and the clamping slider will gradually move toward the clamping base. When the slope at the end of the clamping slider contacts the slope at the edge of the separation retaining ring, the clamping slider will spread outward synchronously. During this process, the sliding part will rotate against the synchronous dial, and the torsion spring between the synchronous dial and the sliding baffle will accumulate elastic potential energy. Step 2: After the clamping slider is expanded, insert the bottom end of the workpiece to be measured between the clamping sliders, then release the shift fork, and the sliding baffle moves away from the separation ring under the elastic force of the mounting seat. When the separation ring and the clamping slider are separated, the synchronous dial will rotate to the limit position under the action of the torsion spring, and pre-clamp the workpiece to be measured through the clamping slider; Then the sliding baffle and the clamping slide block as a whole continue to move away from the clamping base until the arc-shaped convex pattern and the annular groove approach and form a clearance fit, but cannot continue to slide and engage with the next annular groove; Step 3: By extending and retracting the telescopic cylinder, the height of the thermal expansion type fastening clamping mechanism and the manual clamping and releasing assembly located above can be adjusted, thereby changing the relative position between them and the workpiece to be measured; following the same steps as above, the top of the workpiece to be measured can be pre-clamped; Step 4: After the clamping is completed, the electromagnet is energized to apply a pulling force to the armature to retract the telescopic bracket. After the outer stopper loses the limit of the telescopic lock tongue, the induction heating component will drop to the bottom along the vertical guide rod under the action of its own weight; The interior of the heat exchange sleeve is then heated by an induction coil to simulate the actual operating temperature of the material; Step 5: As the temperature rises, the clamping slider and the inner conical cone will change from a clearance fit to an interference fit. At the same time, the clamping slider will squeeze the workpiece under the reaction force of the inner conical cone, thereby increasing the clamping force on the workpiece; at the same time, the arc-shaped convex pattern and the annular groove are further engaged with each other, so that the clamping slider and the inner conical cone are locked by the cooperation of the convex platform and the groove, avoiding the longitudinal relative slip of the clamping slider and the inner conical cone when the interaction force increases; Step 5: When the temperature rises to a specified stable level, apply tension to the workpiece by retracting the telescopic cylinder until the workpiece is broken, and the test is completed; Step 6: After the detection is completed, the interior of the heat exchange sleeve is cooled down by circulating the cooling medium inside the heat exchange sleeve; then the telescopic cylinder is retracted to the top, and the sliding baffle can bring the heat exchange sleeve to the top through the internal stop block when rising, and maintain the position through the top locking assembly.

[0026] The beneficial effects achieved by the present invention using the above structure are as follows: (1) The thermal expansion clamping mechanism uses the heat generated during the environmental simulation process and combines the thermal expansion and contraction characteristics of the metal during heating to automatically switch between the pre-clamping mode and the stable clamping mode. On the one hand, it can reduce the number of moving parts and steps required for manual operation or automatic locking, thereby reducing the complexity of the structure. On the other hand, compared with the traditional threaded tightening method, it can also reduce the wear rate of parts.

[0027] (2) Through the combination of the arc-shaped convex pattern and the annular groove, the clamping slider can form an interference fit with the inner conical cone after expansion, and will not cause longitudinal relative sliding due to the increase of the extrusion pressure between the two, thereby avoiding the influence of the clamping tightness on the process of increasing the extrusion pressure.

[0028] (3) The clamping slider has a more obvious thermal expansion phenomenon after being heated, while the thermal expansion coefficient of the inner conical cone is much smaller. Therefore, when the ambient temperature increases, the clamping slider and the inner conical cone can change from the original clearance fit to the interference fit, thereby achieving stable clamping of the workpiece to be measured; and after the temperature drops, the clamping slider and the inner conical cone can return to the clearance fit state; replacing the traditional mechanical locking mechanism with thermal expansion omits a large number of transmission mechanisms and simplifies the manual operation steps.

[0029] (4) Under the elastic force of the torsion spring, the synchronous dial always has a tendency to push the clamping slider inward. Through the supporting spring, each clamping slider can be tightly attached to the arc portion, thereby achieving the technical effect of synchronously controlling the contraction of the clamping slider.

[0030] (5) By pressing the shift fork, the clamping slides can be actively separated, thereby avoiding the phenomenon of local deformation and difficulty in removal caused by excessive squeezing force of the clamping slide on the workpiece to be tested.

[0031] (6) The induction coil can heat the environment of the workpiece to be tested by induction heating, thereby simulating the working temperature of the workpiece to be tested. The heat exchange sleeve has the function of heat insulation during the heating process, and can be quickly cooled by the flow of internal medium during the cooling process.

[0032] (7) The induction heating component can be pushed to the top by the retraction of the telescopic cylinder and maintained in position by the top locking component. When the fixation is completed and testing is required, it is only necessary to energize the electromagnet, and the induction heating component will fall under the action of its own weight and cover the workpiece to be tested inside itself. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A three-dimensional diagram of a tensile force testing device for austempered ductile iron material proposed by the present invention; Figure 2This is a front view of a tensile force testing device for austempered ductile iron material proposed by the present invention; Figure 3 It is a left view of a tensile force testing device for austempered ductile iron material proposed by the present invention; Figure 4 A top view of a tensile force testing device for isothermal quenching ductile iron material proposed by the present invention; Figure 5 for Figure 2 A cross-sectional view along the cutting line AA; Figure 6 for Figure 3 A cross-sectional view along the cutting line BB; Figure 7 for Figure 5 A cross-sectional view along the cutting line CC; Figure 8 This is a schematic diagram of the explosion structure of a tensile testing device for isothermal quenching ductile iron material proposed by the present invention; Fig. 9 for Figure 5 A partial enlarged view of point Ⅰ in the middle; Fig.10 for Figure 6 A partial enlarged view of the middle II; Fig.11 for Figure 7 A partial enlarged view of the middle part III; Fig.12 for Figure 8 A partial enlarged view of the middle IV; Fig.13 for Figure 6 A partial enlarged view of point V in the middle; Fig.14 Schematic diagram of the positions of the clamping slider and the inner conical table at different temperatures.

[0034] Among them, 1. thermal expansion type fastening clamping mechanism, 2. manual clamping release component, 3. environmental simulation mechanism, 4. frame component, 5. clamping shell component, 6. thermal expansion type anti-slip fastening component, 7. rebound shrinkage clamping component, 8. clamping base, 9. clamping sleeve, 10. workpiece to be measured, 11. sliding baffle, 12. clamping slide block, 13. inner conical frustum, 14. synchronous dial, 15. top support spring, 16. slide groove, 17. polygonal boss, 18. arc convex pattern, 19. sliding part, 20. annular groove, 21. arc part, 22. separation retaining ring , 23. Release lever, 24. Fork, 25. Micro-groove positioning spring, 26. Mounting seat, 27. Lever boss, 28. Induction heating assembly, 29. Lifting assembly, 30. Top locking assembly, 31. Heat exchange sleeve, 32. Upper insulation layer, 33. Induction coil, 34. Telescopic cylinder, 35. Vertical guide rod, 36. Inner stopper, 37. Outer stopper, 38. Telescopic bracket, 39. Telescopic lock tongue, 40. Lock tongue reset spring, 41. Electromagnet, 42. Guide sleeve, 43. Armature, 44. Bottom plate, 45. Frame rack, 46. Top plate.

[0035] The accompanying drawings are used to provide further understanding of the present invention and constitute a part of the specification. They are used to explain the present invention together with the embodiments of the present invention and do not constitute a limitation of the present invention. DETAILED DESCRIPTION

[0036] The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0037] In the description of the present invention, it should be understood that terms such as “upper”, “lower”, “front”, “back”, “left”, “right”, “top”, “bottom”, “inside” and “outside” indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0038] like Figure 1 to Figure 13As shown, the present invention proposes a tension testing device for isothermal quenching ductile iron materials, including a thermal expansion type fastening and clamping mechanism 1, a manual clamping and releasing component 2, an environmental simulation mechanism 3 and a frame component 4, the frame component 4 includes a bottom plate 44, a frame frame 45 and a top plate 46, the frame frame 45 is arranged on the bottom plate 44, and the top plate 46 is arranged on the frame frame 45; the thermal expansion type fastening and clamping mechanism 1 is arranged on the manual clamping and releasing component 2, the manual clamping and releasing component 2 is arranged on the frame component 4 and the environmental simulation mechanism 3, and the environmental simulation mechanism 3 is arranged on the frame component 4.

[0039] The environmental simulation mechanism 3 includes an induction heating component 28, a lifting component 29 and a top locking component 30. The induction heating component 28 is slidably engaged on the lifting component 29, the lifting component 29 is arranged on the top plate 46, and the top locking component 30 is evenly distributed in a ring shape on the outside of the induction heating component 28.

[0040] The lifting assembly 29 includes a telescopic cylinder 34 , a vertical guide rod 35 and an inner stop block 36 . The telescopic cylinder 34 is disposed on the top plate 46 , the vertical guide rod 35 is disposed on the top plate 46 , and the inner stop block 36 is disposed on the induction heating assembly 28 .

[0041] The induction heating assembly 28 includes a heat exchange sleeve 31, an upper heat insulation layer 32 and an induction coil 33. The outer ring of the heat exchange sleeve 31 is evenly distributed with a guide sleeve 42. The heat exchange sleeve 31 is slidably engaged on the vertical guide rod 35 through the guide sleeve 42. The upper heat insulation layer 32 is arranged at the top of the heat exchange sleeve 31. The induction coil 33 is arranged inside the heat exchange sleeve 31, and the inner stop block 36 is fixed to the inner wall of the heat exchange sleeve 31.

[0042] The induction coil 33 can heat the environment of the workpiece 10 to be tested by induction heating, thereby simulating the working temperature of the workpiece 10 to be tested. The heat exchange sleeve 31 has a heat insulation effect during the heating process, and can be quickly cooled by the flow of internal medium during the cooling process.

[0043] The top locking assembly 30 includes an outer stopper 37 , which is fixed to the top of the outer wall of the heat exchange sleeve 31 . The height of the inner stopper 36 is lower than that of the outer stopper 37 . A tension sensor is provided at the end of the telescopic cylinder 34 .

[0044] The induction heating assembly 28 can be pushed to the top by the retraction of the telescopic cylinder 34 and maintained in position by the top locking assembly 30; when the fixation is completed and testing is required, it is only necessary to energize the electromagnet 41, and the induction heating assembly 28 will fall under the action of its own weight and cover the workpiece 10 to be tested inside itself.

[0045] The top locking assembly 30 also includes a telescopic bracket 38, a telescopic lock tongue 39, a lock tongue reset spring 40 and an electromagnet 41. The telescopic bracket 38 is arranged on the top plate 46, the telescopic lock tongue 39 is slidably arranged in the telescopic bracket 38, an armature 43 is provided at the tail of the telescopic lock tongue 39, the lock tongue reset spring 40 is arranged between the telescopic lock tongue 39 and the telescopic bracket 38, and the electromagnet 41 is arranged on the top plate 46, and the positions of the electromagnet 41 and the armature 43 correspond to each other.

[0046] The springs in the present solution all have high temperature resistance characteristics and will not have a significant impact on the compression rebound performance at the working temperature of the present invention.

[0047] The thermal expansion type fastening clamping mechanism 1 includes a clamping shell component 5, a thermal expansion type anti-detachment fastening component 6 and a rebound shrinkage clamping component 7. The clamping shell component 5 is arranged on the manual clamping and releasing component 2, the thermal expansion type anti-detachment fastening component 6 is arranged in the clamping shell component 5, and the rebound shrinkage clamping component 7 is arranged on the thermal expansion type anti-detachment fastening component 6.

[0048] The thermal expansion fastening clamping mechanism 1 utilizes the heat inherent in the environmental simulation process and combines the thermal expansion and contraction characteristics of the metal during heating to automatically switch between the pre-clamping mode and the stable clamping mode. On the one hand, it can reduce the moving parts and steps required for manual operation or automatic locking, and reduce the complexity of the structure; on the other hand, compared with the traditional threaded tightening and fixing method, it can also reduce the wear rate of parts.

[0049] The thermal expansion type fastening clamping mechanism 1 and the manual clamping and releasing assembly 2 are symmetrically arranged in two groups. The clamping shell assembly 5 includes a clamping base 8 and a clamping sleeve 9. The clamping base 8 is arranged on the manual clamping and releasing assembly 2, and the clamping sleeve 9 is arranged on the clamping base 8.

[0050] The thermal expansion anti-slip fastening assembly 6 includes a sliding baffle 11, a clamping slider 12 and an inner conical cone 13. The sliding baffle 11 is snap-fitted and slidably arranged in the clamping sleeve 9. The sliding baffle 11 is provided with a circular evenly distributed sliding groove 16. The clamping slider 12 is provided with a sliding portion 19. The sliding portion 19 is snap-fitted and slidably arranged in the sliding groove 16. The outer conical surface of the clamping slider 12 is provided with an array of arc-shaped convex patterns 18. The inner conical cone 13 is fixedly connected to the inside of the clamping sleeve 9. The inner conical surface of the inner conical cone 13 is provided with an array of annular grooves 20 matching the arc-shaped convex patterns 18.

[0051] Through the combination of the arcuate convex pattern 18 and the annular groove 20, the clamping slider 12 can form an interference fit with the inner conical cone 13 after expansion, without longitudinal relative sliding due to the increase of the extrusion pressure between the two, thereby avoiding the influence of the clamping tightness during the increase of the extrusion pressure.

[0052] The two ends of the workpiece 10 to be measured are clamped by a clamping slider 12; the clamping slider 12 is made of a metal material that expands after being heated, and the inner conical frustum 13 is made of Si3N4 silicon nitride ceramic material.

[0053] The clamping slider 12 has a more obvious thermal expansion phenomenon after being heated, while the thermal expansion coefficient of the inner conical cone 13 is much smaller. Therefore, when the ambient temperature increases, the clamping slider 12 and the inner conical cone 13 can be transformed from the original clearance fit to an interference fit, thereby achieving stable clamping of the workpiece 10 to be measured; and after the temperature drops, the clamping slider 12 and the inner conical cone 13 can be restored to the clearance fit state; the traditional mechanical locking mechanism is replaced by thermal expansion, which omits a large number of transmission mechanisms and simplifies the manual operation steps.

[0054] A polygonal boss 17 is also provided at the center position of the sliding baffle 11, and the number of sides of the polygonal boss 17 is equal to the number of sliding grooves 16. The rebound and contraction clamping assembly 7 includes a synchronous dial 14 and a support spring 15. The support spring 15 is arranged between the side of the polygonal boss 17 and the sliding portion 19. The synchronous dial 14 is rotatably arranged on the sliding baffle 11, and the synchronous dial 14 and the sliding baffle 11 are connected by a torsion spring; the inner ring of the synchronous dial 14 is evenly distributed with arc portions 21 matching the sliding portion 19. Under the elastic force of the torsion spring, the synchronous dial 14 has the function of pushing the clamping slider 12 to contract synchronously through its own rotation.

[0055] Under the elastic force of the torsion spring, the synchronous dial 14 always tends to push the clamping slider 12 inward. Through the supporting spring 15, each clamping slider 12 can be tightly attached to the arc portion 21, thereby achieving the technical effect of synchronously controlling the contraction of the clamping slider 12.

[0056] The manual clamping and releasing assembly 2 includes a separation ring 22, a release lever 23, a shift fork 24, a micro-groove positioning spring 25 and a mounting seat 26. The separation ring 22 is fixedly connected to the clamping base 8, the release lever 23 is arranged on the polygonal boss 17, the release lever 23 is slidably arranged in the clamping base 8, the end of the release lever 23 is provided with a lever boss 27, the shift fork 24 is rotatably arranged on the outside of the clamping base 8, the micro-groove positioning spring 25 is arranged between the clamping base 8 and the polygonal boss 17, one of the mounting seats 26 is arranged on the bottom plate 44, the other of the mounting seats 26 is arranged on the pulling assembly 29, and the clamping base 8 is arranged on the mounting seat 26.

[0057] By pressing the shift fork 24 , the clamping slide blocks 12 can be actively separated, thereby avoiding the phenomenon of local deformation and difficulty in removal caused by excessive squeezing force of the clamping slide blocks 12 on the workpiece 10 to be measured.

[0058] like Fig.14As shown, part (a) shows the relative position of the clamping slider 12 and the inner conical cone 13 in a clearance fit under normal temperature; part (b) shows the relative position of the clamping slider 12 and the inner conical cone 13 in an interference fit under high temperature, and the arc-shaped convex pattern 18 and the annular groove 20 are engaged with each other.

[0059] When used specifically, before clamping the workpiece 10 to be measured, the induction heating assembly 28 is fixed at the top by the top locking assembly 30, and then the two ends of the workpiece 10 to be measured are clamped and fixed in turn, and the lower end of the workpiece 10 to be measured is clamped and fixed first; The end of the shift fork 24 is pressed toward the clamping base 8. When the shift fork 24 pulls out the release lever 23, the sliding baffle 11 and the clamping slider 12 gradually approach the clamping base 8. When the slope at the end of the clamping slider 12 contacts the slope at the edge of the separation retaining ring 22, the clamping slider 12 will spread outward synchronously. During this process, the sliding portion 19 will rotate against the synchronous dial 14, and the torsion spring between the synchronous dial 14 and the sliding baffle 11 will accumulate elastic potential energy. After the clamping slide block 12 is expanded, the bottom end of the workpiece 10 to be measured is inserted between the clamping slide blocks 12, and then the shift fork 24 is released. The sliding baffle 11 moves away from the separation ring 22 under the elastic force of the mounting seat 26. When the separation ring 22 and the clamping slide block 12 are separated, the synchronous dial 14 rotates to the limit position under the action of the torsion spring. At this position, the clamping slide block 12 contacts the workpiece 10 to be measured and pre-clamps the workpiece 10 to be measured. Then the sliding baffle 11 and the clamping slide block 12 continue to move away from the clamping base 8 as a whole until the arc-shaped convex pattern 18 and the annular groove 20 approach and form a clearance fit, but cannot continue to slide and engage with the next annular groove 20; due to the difference in specifications of the diameters of the workpieces 10 to be measured, when clamping workpieces 10 to be measured with different diameters, although the relative heights of the clamping slide block 12 and the inner conical table 13 are different, they will stop at the position where the arc-shaped convex pattern 18 and the annular groove 20 form a clearance fit.

[0060] By extending and retracting the telescopic cylinder 34, the height of the thermal expansion type fastening clamping mechanism 1 and the manual clamping and releasing assembly 2 located above can be adjusted, thereby changing the relative position between them and the workpiece 10 to be measured; according to the same steps as above, the top of the workpiece 10 to be measured can be pre-clamped.

[0061] After the clamping is completed, the electromagnet 41 is energized to apply a pulling force to the armature 43, so that the telescopic bracket 38 retracts. After the outer stopper 37 loses the limit of the telescopic lock tongue 39, the induction heating assembly 28 will drop to the bottom along the vertical guide rod 35 under the action of its own weight; The interior of the heat exchange sleeve 31 is then heated by the induction coil 33 to simulate the actual working temperature of the material.

[0062] As the temperature rises, since the thermal expansion coefficient of the clamping slider 12 is much greater than that of the inner conical cone 13, the clamping slider 12 and the inner conical cone 13 will change from a clearance fit to an interference fit. At the same time, the clamping slider 12 will also squeeze the workpiece 10 to be measured under the reaction force of the inner conical cone 13, thereby increasing the clamping force on the workpiece 10 to be measured; at the same time, the arc-shaped convex pattern 18 and the annular groove 20 are further engaged with each other, so that the clamping slider 12 and the inner conical cone 13 are locked by the cooperation of the convex platform and the groove, so as to avoid the longitudinal relative slip of the clamping slider 12 and the inner conical cone 13 when the interaction force increases; At this point, the workpiece 10 to be measured is stably clamped.

[0063] When the temperature rises to a specified stable level, the telescopic cylinder 34 retracts to apply tension to the workpiece 10 until the workpiece 10 is broken, and the test is completed. At the same time, the tension sensor at the end of the telescopic cylinder 34 and other necessary sensors can monitor and feedback the measurement results.

[0064] After the detection is completed, the interior of the heat exchange sleeve 31 is cooled down by circulating the cooling medium inside the heat exchange sleeve 31; then the telescopic cylinder 34 is retracted to the top, and the sliding baffle 11 can bring the heat exchange sleeve 31 to the top through the internal stop block 36 when rising, and maintain the position through the top locking assembly 30.

[0065] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0066] The present invention and its embodiments are described above, and such description is not restrictive. The drawings show only one embodiment of the present invention, and the actual structure is not limited thereto. In short, if ordinary technicians in the field are inspired by it, without departing from the purpose of the invention, they can design a structure and embodiment similar to the technical solution without creativity, which should belong to the protection scope of the present invention.

Claims

1. A tensile testing device for isothermally quenched ductile iron material, comprising a frame assembly (4), the frame assembly (4) comprising a bottom plate (44), a frame frame (45) and a top plate (46), the frame frame (45) being arranged on the bottom plate (44), and the top plate (46) being arranged on the frame frame (45); characterized in that: It also comprises a thermal expansion type fastening and clamping mechanism (1), a manual clamping and releasing component (2) and an environmental simulation mechanism (3), wherein the thermal expansion type fastening and clamping mechanism (1) is arranged on the manual clamping and releasing component (2), the manual clamping and releasing component (2) is arranged on the frame component (4) and the environmental simulation mechanism (3), and the environmental simulation mechanism (3) is arranged on the frame component (4); The thermal expansion type fastening clamping mechanism (1) comprises a clamping shell component (5), a thermal expansion type anti-detachment fastening component (6) and a rebound shrinkage clamping component (7), wherein the clamping shell component (5) is arranged on the manual clamping release component (2), the thermal expansion type anti-detachment fastening component (6) is arranged in the clamping shell component (5), and the rebound shrinkage clamping component (7) is arranged on the thermal expansion type anti-detachment fastening component (6); The environmental simulation mechanism (3) comprises an induction heating component (28), a lifting component (29) and a top locking component (30); the induction heating component (28) is slidably mounted on the lifting component (29); the lifting component (29) is disposed on a top plate (46); and the top locking component (30) is evenly distributed in a ring shape on the outside of the induction heating component (28).

2. The tensile testing device for austempered ductile iron material according to claim 1, characterized in that: The thermal expansion type fastening clamping mechanism (1) and the manual clamping and releasing assembly (2) are symmetrically arranged in two groups, the clamping shell assembly (5) comprises a clamping base (8) and a clamping sleeve (9), the clamping base (8) is arranged on the manual clamping and releasing assembly (2), and the clamping sleeve (9) is arranged on the clamping base (8).

3. A tensile testing device for austempered ductile iron material according to claim 2, characterized in that: The thermal expansion type anti-slip fastening assembly (6) comprises a sliding baffle (11), a clamping slider (12) and an inner conical cone (13); the sliding baffle (11) is slidably engaged in the clamping sleeve (9); the sliding baffle (11) is evenly distributed with sliding grooves (16) in an annular manner; the clamping slider (12) is provided with a sliding portion (19); the sliding portion (19) is slidably engaged in the sliding grooves (16); the outer conical surface of the clamping slider (12) is provided with arcuate convex patterns (18) in an array; the inner conical cone (13) is fixedly connected to the inside of the clamping sleeve (9); the inner conical surface of the inner conical cone (13) is provided with annular grooves (20) matching the arcuate convex patterns (18) in an array.

4. A tensile testing device for austempered ductile iron material according to claim 3, characterized in that: The two ends of the workpiece (10) to be measured are clamped by a clamping slider (12); the clamping slider (12) is made of a metal material that expands after being heated, and the inner conical frustum (13) is made of Si3N4 silicon nitride ceramic material.

5. A tensile testing device for austempered ductile iron material according to claim 4, characterized in that: A polygonal boss (17) is also provided at the center of the sliding baffle (11), the number of sides of the polygonal boss (17) being equal to the number of the slide grooves (16); the rebound and contraction clamping assembly (7) comprises a synchronous dial (14) and a supporting spring (15), the supporting spring (15) being provided between the side of the polygonal boss (17) and the sliding portion (19); the synchronous dial (14) is rotatably provided on the sliding baffle (11), and the synchronous dial (14) and the sliding baffle (11) are connected via a torsion spring; the inner ring of the synchronous dial (14) is evenly distributed with arc portions (21) matching the sliding portion (19); under the elastic force of the torsion spring, the synchronous dial (14) has the function of pushing the clamping slider (12) to contract synchronously through its own rotation.

6. The tensile testing device for austempered ductile iron material according to claim 5, characterized in that: The manual clamping and releasing assembly (2) comprises a separation ring (22), a release lever (23), a shift fork (24), a micro-groove positioning spring (25) and a mounting seat (26); the separation ring (22) is fixedly connected to the clamping base (8); the release lever (23) is arranged on the polygonal boss (17); the release lever (23) is slidably arranged in the clamping base (8); a lever boss (27) is arranged at the end of the release lever (23); the shift fork (24) is rotatably arranged outside the clamping base (8); the micro-groove positioning spring (25) is arranged between the clamping base (8) and the polygonal boss (17); one of the mounting seats (26) is arranged on the bottom plate (44); the other of the mounting seats (26) is arranged on the lifting assembly (29); and the clamping base (8) is arranged on the mounting seat (26).

7. The tensile testing equipment for austempered ductile iron material according to claim 1, characterized in that: The lifting assembly (29) comprises a telescopic cylinder (34), a vertical guide rod (35) and an inner stopper (36); the telescopic cylinder (34) is arranged on a top plate (46); the vertical guide rod (35) is arranged on the top plate (46); and the inner stopper (36) is arranged on the induction heating assembly (28).

8. The tensile testing device for austempered ductile iron material according to claim 7, characterized in that: The induction heating assembly (28) comprises a heat exchange sleeve (31), an upper heat insulation layer (32) and an induction coil (33); a guide sleeve (42) is evenly distributed in an annular shape on the outside of the heat exchange sleeve (31); the heat exchange sleeve (31) is slidably mounted on a vertical guide rod (35) through the guide sleeve (42); the upper heat insulation layer (32) is disposed at the top of the heat exchange sleeve (31); the induction coil (33) is disposed inside the heat exchange sleeve (31); and the inner stopper (36) is fixedly connected to the inner wall of the heat exchange sleeve (31).

9. The tensile testing device for austempered ductile iron material according to claim 8, characterized in that: The top locking assembly (30) comprises an outer stopper (37), the outer stopper (37) being fixedly connected to the top end of the outer wall of the heat exchange sleeve (31), and the height of the inner stopper (36) being lower than the height of the outer stopper (37); a tension sensor is provided at the end of the telescopic cylinder (34); The top locking assembly (30) further comprises a telescopic bracket (38), a telescopic lock tongue (39), a lock tongue reset spring (40) and an electromagnet (41); the telescopic bracket (38) is arranged on the top plate (46); the telescopic lock tongue (39) is slidably arranged in the telescopic bracket (38); an armature (43) is arranged at the tail of the telescopic lock tongue (39); the lock tongue reset spring (40) is arranged between the telescopic lock tongue (39) and the telescopic bracket (38); the electromagnet (41) is arranged on the top plate (46); and the positions of the electromagnet (41) and the armature (43) correspond to each other.

10. The method for using the tension testing device for austempered ductile iron material according to any one of claims 6 and 9, characterized in that: The steps include: Step 1: Before clamping the workpiece (10) to be tested, the induction heating component (28) is fixed at the top by the top locking component (30), and then the two ends of the workpiece (10) to be tested are clamped and fixed in turn, firstly clamping and fixing the lower end of the workpiece (10) to be tested; The end of the shift fork (24) is pressed toward the clamping base (8). When the shift fork (24) pulls out the release lever (23), the sliding baffle (11) and the clamping slider (12) gradually move toward the clamping base (8). When the slope at the end of the clamping slider (12) contacts the slope at the edge of the separation retaining ring (22), the clamping slider (12) will spread outward synchronously. During this process, the sliding portion (19) rotates against the synchronous dial (14), and the torsion spring between the synchronous dial (14) and the sliding baffle (11) accumulates elastic potential energy. Step 2: After the clamping slide block (12) is expanded, the bottom end of the workpiece (10) to be measured is inserted between the clamping slide blocks (12), and then the shift fork (24) is released. The sliding baffle (11) moves away from the separation baffle ring (22) under the elastic force of the mounting seat (26). When the separation baffle ring (22) and the clamping slide block (12) are separated, the synchronous dial (14) rotates to the limit position under the action of the torsion spring, and pre-clamps the workpiece (10) to be measured through the clamping slide block (12); Then, the sliding baffle (11) and the clamping slide block (12) as a whole continue to move away from the clamping base (8) until the arc-shaped convex pattern (18) and the annular groove (20) approach and form a clearance fit, but cannot continue to slide and engage with the next annular groove (20); Step 3: By extending and retracting the telescopic cylinder (34), the height of the thermal expansion type fastening clamping mechanism (1) and the manual clamping and releasing assembly (2) located above can be adjusted, thereby changing the relative position between them and the workpiece to be measured (10); following the same steps as above, the top end of the workpiece to be measured (10) can be pre-clamped; Step 4: After the clamping is completed, the electromagnet (41) is energized to apply a pulling force to the armature (43), so that the telescopic bracket (38) retracts. After the outer stopper (37) loses the limit of the telescopic lock tongue (39), the induction heating component (28) will descend to the bottom along the vertical guide rod (35) under the action of its own weight; The interior of the heat exchange sleeve (31) is then heated by an induction coil (33) to simulate the actual working temperature of the material; Step 5: As the temperature rises, the clamping slider (12) and the inner conical cone (13) will change from a clearance fit to an interference fit, and at the same time, the clamping slider (12) will squeeze the workpiece (10) to be measured under the reaction force of the inner conical cone (13), thereby increasing the clamping force on the workpiece (10) to be measured; at the same time, the arc-shaped convex pattern (18) and the annular groove (20) are further engaged with each other, so that the clamping slider (12) and the inner conical cone (13) are locked by the cooperation of the convex platform and the groove, thereby preventing the clamping slider (12) and the inner conical cone (13) from generating longitudinal relative slip when the interaction force increases; Step 5: When the temperature rises to a specified stable temperature, a tensile force is applied to the workpiece (10) to be tested by retracting the telescopic cylinder (34) until the workpiece (10) to be tested is broken, and the test is completed; Step 6: After the detection is completed, the interior of the heat exchange sleeve (31) is cooled by circulating the cooling medium inside the heat exchange sleeve (31); then the telescopic cylinder (34) is retracted to the top end, and the sliding baffle (11) can bring the heat exchange sleeve (31) to the top end through the inner block (36) when rising, and maintain the position through the top locking assembly (30).

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