Sample vibration fatigue test device in high-temperature environment

Abstract

The invention discloses a test sample vibration fatigue test device in a high-temperature environment, and belongs to the field of material performance testing. The test sample vibration fatigue test device in the high-temperature environment comprises a frame; the vibration device is used for applying vibration acting force to the test sample in the test process; the high-temperature environment device comprises a cover body, a heating assembly and a fixed seat, and the fixed seat is fixedly arranged on the frame; the sample clamp is used for arranging a sample in the cavity, is detachably arranged in the high-temperature environment device and is connected with the vibration device; the lifting device is used for driving the cover body to be in contact with or away from the fixed seat; the water supply cooling device and the air supply device are respectively connected with the sample clamp. The test sample is fixed in the high-temperature environment device by the test sample clamp, and vibration acting force is applied to the test sample through the vibration device, so that the test sample is subjected to a fatigue test under the synergistic effect of high-frequency vibration and high temperature, and technical support is provided for material optimization design and safety analysis.

Description

Technical Field

[0001] The present invention relates to the field of material property testing, and particularly to a specimen vibration fatigue test device for high-temperature environments. Background Art

[0002] With the rapid development of technologies such as aerospace, hypersonic aircraft, and reusable launch vehicles, the power systems of aircraft (such as aeroengines, ramjets) and thermal protection structures face more severe challenges in extreme service environments. During high-speed flight or reentry into the atmosphere, the surfaces and key components of the aircraft need to withstand a high-temperature environment of 1300 - 1600 °C for a long time, and are superimposed with high-frequency vibration loads (usually in the frequency range of 1 - 10 kHz) caused by high-speed airflow, engine combustion oscillation, or mechanical transmission. Under this combined working condition, the material not only undergoes thermodynamic behaviors such as high-temperature oxidation, creep, and phase transformation, but also dynamic failure problems such as fatigue crack initiation and propagation, interface debonding, and coating spalling caused by high-frequency vibration, seriously threatening the reliability and life of the aircraft.

[0003] Currently, the performance testing of high-temperature resistant materials (such as ceramic matrix composites, ultra-high temperature ceramics, carbon / carbon composites, etc.) mostly focuses on the action of a single environmental factor. For example, traditional high-temperature mechanical testing equipment usually adopts static or quasi-static loading modes and cannot simulate the synergistic effect of high-frequency vibration and high temperature; while conventional vibration testing devices are limited by the temperature control accuracy of the heating system and the temperature resistance performance of the vibration exciter, and it is difficult to achieve stable high-frequency dynamic loading above 1300 °C. In addition, existing high-temperature vibration coupling testing technologies are mostly designed for low-frequency (<500 Hz) or medium-frequency (500 - 2000 Hz) ranges, and the maximum test temperature is usually lower than 1200 °C, and there is a significant gap between their test conditions and the actual service environment. This results in the inability to accurately evaluate the dynamic mechanical responses of materials in practical applications (such as high-temperature vibration fatigue life, damping characteristics, crack propagation rate, etc.), thereby affecting the material optimization design and safety analysis.

[0004] Based on this, there is an urgent need to develop a testing device applicable to the ultra-high temperature environment of 1300 - 1600 °C that can apply high-frequency vibration loads to accurately simulate the service behavior of aircraft materials under extreme multi-physical field coupling conditions. Summary of the Invention

[0005] In view of this, the present invention provides a specimen vibration fatigue test device for high-temperature environments, and the main purpose is to simulate the synergistic effect of high-frequency vibration and high temperature of materials, providing technical support for further optimization design and safety analysis.

[0006] To achieve the above purpose, the present invention provides the following technical solutions:

[0007] A vibration fatigue test device for specimens in a high-temperature environment, comprising:

[0008] A frame;

[0009] A vibration device, which is inside the frame and is used to apply a vibration force to the specimen during the test; the vibration device is one of a pneumatic shaker and an electromagnetic shaker;

[0010] A high-temperature environment device, which is on the frame; the high-temperature environment device includes a cover body, a heating component fixedly arranged inside the cover body, and a fixing seat movably connected to the cover body, and the fixing seat is fixedly arranged on the frame; when the cover body and the fixing seat are connected, a cavity is formed inside the cover body and the fixing seat; a clamp placement hole is vertically penetrated and opened at the central position of the fixing seat;

[0011] A specimen clamp, which is detachably arranged in the clamp placement hole and is connected to the vibration device, and the specimen clamp is used to place the specimen in the cavity; the specimen clamp corresponds to the vibration device and the high-temperature environment device up and down respectively;

[0012] A lifting device, which is arranged on the frame, and the lifting device is fixedly connected to the outer wall of the cover body, and the lifting device is used to drive the cover body to contact or move away from the fixing seat; and

[0013] A water supply cooling device and a gas supply device respectively connected to the specimen clamp.

[0014] According to the foregoing vibration fatigue test device for specimens in a high-temperature environment, the heating component includes:

[0015] A heating wire, which is arranged on the inner wall of the cover body;

[0016] A temperature sensor, which is arranged inside the cover body to detect the temperature of the cavity.

[0017] According to the foregoing vibration fatigue test device for specimens in a high-temperature environment, the lifting device includes:

[0018] A bracket, which is arranged on the frame;

[0019] A linear driving device, which is arranged on the bracket; and

[0020] A connecting component, part of which is fixedly connected to the output end of the linear driving device, and part of which is fixedly connected to the outside of the cover body;

[0021] A guiding component, part of whose components are arranged on the bracket and part of whose components are arranged on the connecting component;

[0022] The linear driving device drives the connecting component, and then the cover body contacts or moves away from the fixing seat.

[0023] Furthermore, the lifting device further includes:

[0024] The drag chain has one end provided on the connection component and the other end provided on the bracket.

[0025] Furthermore, the guiding component includes:

[0026] A slide rail vertically fixed on the bracket; and

[0027] A slider slidably connected to the slide rail, and the slider is fixedly connected to the connection component;

[0028] There are two sets of guiding components, respectively arranged on the left and right sides of the bracket.

[0029] Furthermore, the connection component includes:

[0030] A cover body support plate, which is circular ring-shaped, and the opening end face of the cover body is fixedly connected to the upper surface of the cover body support plate;

[0031] A connecting plate arranged on one side of the cover body support plate and perpendicular to the upper surface of the cover body support plate;

[0032] A sliding connecting plate, one side of which is fixedly connected to the connecting plate and the other side is fixedly connected to the slider; and

[0033] A linear drive connecting plate, which is an inverted L-shaped plate, including a horizontal part and a vertical part. The horizontal part is fixedly connected to the output end of the linear drive device, and the vertical part is fixedly connected to the top of the sliding connecting plate on the same side as the slider.

[0034] According to the foregoing specimen vibration fatigue test device for high-temperature environment, the specimen is a strip-shaped specimen or a spring-shaped specimen;

[0035] The specimen fixture includes:

[0036] A pipe body component, which includes an outer sleeve pipe and a central pipe. The central pipe is partially located inside the outer sleeve pipe and is coaxially arranged with the outer sleeve pipe; the tops of the outer sleeve pipe and the central pipe are flush, and the tops of both are connected by an upper end plate; the bottom end of the central pipe extends out of the outer sleeve pipe, and the bottom end of the outer sleeve pipe is connected to the outer side wall of the central pipe through a lower end plate; a sealing plate is arranged at the bottom end of the central pipe, and the top end of the central pipe is open; the space gap between the outer sleeve pipe and the central pipe is a condensation channel, and multiple water pipes are evenly arranged around the central axis in the condensation channel. The water pipes penetrate through the lower end plate and extend to the outside of the central pipe, and the water pipes are connected to the water supply and cooling device;

[0037] The pipe body cap has a cavity inside. The top end of the outer sleeve is sleeved inside the cavity. The pipe body cap is detachably connected to the outer sleeve. The top end surface of the cavity of the pipe body cap is spaced from the top end surface of the upper end plate. An opening is provided at the center of the upper end of the pipe body cap, which is communicated with the cavity. An unpenetrated cap sample placement groove is provided at the top of the upper end of the pipe body cap. The cap sample placement groove includes a cap long sample placement groove and a cap spring sample placement groove. A sleeve placement groove is provided at the top end of the cavity of the pipe body cap. An air vent is provided at the upper end of the pipe body cap, which is communicated with the cavity.

[0038] The top end cap is spaced above the pipe body cap. A penetrating top end cap opening is provided at the center of the top end cap. An unpenetrated end cap long sample placement groove is provided on the lower end surface of the top end cap. The two ends of the long strip sample are respectively in the cap long sample placement groove and the end cap long sample placement groove. One end of the spring sample is in the cap spring sample placement groove, and the other end of the spring sample abuts against the lower end surface of the top end cap.

[0039] The sleeve is arranged inside the central pipe and coaxially with the central pipe. The top end of the sleeve is an open end, and the open end abuts in the sleeve placement groove. A sleeve through hole is provided at the bottom end of the sleeve.

[0040] The connecting screw rod, the screw rod part of the connecting screw rod sequentially penetrates through the top end cap opening of the top end cap, the cap opening of the pipe body cap and the sleeve and continues to extend into the inner cavity of the central pipe. The connecting screw rod is in clearance fit with the cap opening and the sleeve through hole respectively. The top end part of the connecting screw rod abuts against the top surface of the top end cap.

[0041] The connecting nut is arranged at one end of the screw rod part far from the top end part.

[0042] The compensating spring, its upper end abuts against the bottom end of the sleeve, and its lower end abuts against the connecting nut.

[0043] The air inlet connecting piece is arranged on the side wall near the bottom end of the central pipe and is communicated with the central pipe. Part of the air inlet connecting piece is connected to the air supply device; and

[0044] The base, the sealing plate of the pipe body assembly is detachably connected to the base, and the bottom end surface of the base is connected to the vibration device.

[0045] Furthermore, an external thread is provided on the side wall of the top end of the outer sleeve, and an internal thread adapted to the external thread is provided on the side wall of the cavity of the pipe body cap;

[0046] The pipe body cap is threadedly connected to the outer sleeve.

[0047] Furthermore, the sample fixture further includes a fastening component for preventing the pipe body cap and the outer sleeve from loosening;

[0048] The fastening component includes an anti-rotation pin;

[0049] A first limiting hole communicating with the cavity is provided at the central position of the upper end of the pipe body cap, and an unpenetrating second limiting hole is provided on the upper end surface of the upper end plate. After the pipe body cap is connected to the outer sleeve, the first limiting hole and the second limiting hole correspond up and down, and the anti-rotation pin sequentially passes through the first limiting hole and the second limiting hole;

[0050] The fastening assembly further includes a fastening nut provided at the lower end of the pipe body cap and threadedly connected to the outer sleeve.

[0051] According to the foregoing specimen vibration fatigue test device in a high-temperature environment, the device further includes:

[0052] A control device, which is electrically connected to the vibration device, the heating assembly, the lifting device, the water supply and cooling device, and the gas supply device respectively.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] (1) A specimen vibration fatigue test device in a high-temperature environment provided by the present invention fixes the specimen inside the high-temperature environment device by the specimen fixture, and applies a vibration force to the specimen through the vibration device, so as to perform a fatigue test on the specimen under the synergistic effect of high-frequency vibration and high temperature. Compared with the prior art, the present invention improves the applicable range of the specimen vibration fatigue test device, and can perform specimen fatigue tests on specimens in a high-temperature, inert gas environment of up to 1300 °C to 1600 °C.

[0055] (2) The lifting device is used to drive the cover body to contact or move away from the fixed seat. The lifting device raises the cover body upward so that the cover body is in a position away from the fixed seat, which is convenient for placing the specimen fixture on the fixed seat; the lifting device moves the cover body downward so that the cover body is in contact with the fixed seat to form a cavity.

[0056] (3) A multi-directional stable connection system is formed in the specimen fixture to ensure the axial force stability of the specimen during the test. The shape and position matching between the end of the specimen and the differential placement groove; the transition fit between the open end of the sleeve and the sleeve placement groove; the pipe body assembly forms a rigid connection with the base through the sealing plate. Description of the Drawings

[0057] Figure 1 Isometric view of the specimen vibration fatigue test device in a high-temperature environment Figure 1 ;

[0058] Figure 2 Isometric view of the specimen vibration fatigue test device in a high-temperature environment Figure 2 ;

[0059] Figure 3 Is a cross-sectional view of the specimen vibration fatigue test device in a high-temperature environment;

[0060] Figure 4Stereogram of the connection state of the frame, vibration device and fixed seat;

[0061] Figure 5 Stereogram of the connection state of the vibration device and the specimen fixture;

[0062] Figure 6 Stereogram of the lifting device Figure 1 ;

[0063] Figure 7 Stereogram of the lifting device Figure 2 ;

[0064] Figure 8 Stereogram of the combined state of the guiding component and the connecting component of the lifting device;

[0065] Figure 9 Stereogram of the combined state of the specimen fixture and the strip-shaped specimen;

[0066] Figure 10 For Figure 9 Partial enlarged view at position A in ;

[0067] Figure 11 Partial stereogram of the combined state of the specimen fixture and the spring-shaped specimen;

[0068] Figure 12 Cross-sectional view of the combined state of the specimen fixture and the spring-shaped specimen;

[0069] Figure 13 For Figure 12 Partial enlarged view at position B in ;

[0070] Figure 14 Stereogram of the pipe body assembly;

[0071] Figure 15 Cross-sectional view of the pipe body assembly;

[0072] Figure 16 Stereogram of the pipe body cap;

[0073] Figure 17 Cross-sectional view of the pipe body cap;

[0074] Figure 18 Stereogram of the top cover;

[0075] Figure 19 Cross-sectional view of the top cover;

[0076] Figure 20 Cross-sectional view of the sleeve;

[0077] Figure 21 Front view of the connecting screw;

[0078] Figure 22It is a perspective view of the base.

[0079] Description of the reference numerals in the drawings:

[0080] 1. Frame; 11. Bottom plate; 12. Column; 13. Workbench;

[0081] 2. Vibration device;

[0082] 3. High-temperature environment device; 31. Cover; 32. Heating component; 33. Fixed seat; 34. Cavity; 35. Fixture placement hole; 321. Heating wire; 322. Temperature sensor;

[0083] 4. Specimen fixture; 41. Tube assembly; 42. Tube cap; 43. Top end cap; 44. Sleeve; 45. Connecting screw; 46. Connecting nut; 47. Compensation spring; 48. Intake connection; 49. Base; 411. Outer sleeve; 412. Central tube; 413. Upper end plate; 414. Lower end plate; 415. Sealing plate; 416. Condensation channel; 417. Water pipe; 421. Cavity; 422. Cap opening; 423. Cap specimen placement groove; 424. Sleeve placement groove; 425. Air outlet; 426. First limit hole; 431. Top end cap opening; 432. End cap long specimen placement groove; 441. Open end; 442. Sleeve through hole; 451. Screw part; 452. Top end part; 412a. Intake port; 413a. Second limit hole; 423a. Cap long specimen placement groove; 423b. Cap spring specimen placement groove; 4a. Anti-rotation pin; 4b. Fastening nut;

[0084] 5. Lifting device; 51. Bracket; 52. Guide component; 53. Linear drive device; 54. Connecting component; 55. Drag chain; 521. Slide rail; 522. Slide block; 541. Cover support plate; 542. Link plate; 543. Sliding connection plate; 544. Linear drive connection plate; 545. Rib plate connection plate; 546. Rib plate; 544a. Horizontal part; 544b. Vertical part;

[0085] 100. Long strip specimen;

[0086] 200. Spring-shaped specimen. Detailed implementation manners

[0087] To make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the drawings Figures 1 to 22 and specific embodiments.

[0088] An embodiment of the present invention provides a vibration fatigue test device for specimens in a high-temperature environment, comprising: a frame 1; a vibration device 2, which is inside the frame 1 and is used to apply a vibration force to the specimen during the test; a high-temperature environment device 3, which is on the frame 1 and is used to provide a high-temperature environment for the specimen; a specimen fixture 4, which is detachably arranged on the high-temperature environment device 3 and is connected to the vibration device 2. The specimen fixture 4 is used to place the specimen in the high-temperature environment device 3 and transfer the vibration of the vibration device 2 to the specimen; the specimen fixture 4 corresponds to the vibration device 2 and the high-temperature environment device 3 up and down; a lifting device 5, which is arranged on the frame 1 and is partially fixedly connected to the high-temperature environment device 3, and the lifting device 5 is used to drive the partial movement of the high-temperature environment device 3; a water supply cooling device (not shown in the figure), which is connected to the specimen fixture 4 and can prevent the inside of the specimen fixture 4 from getting too hot; and a gas supply device (not shown in the figure), which is connected to the specimen fixture 4 and is used to provide an inert gas environment for the specimen in the high-temperature environment.

[0089] The frame 1 includes a bottom plate 11, upright columns 12 and a workbench 13. The bottom plate 11 is arranged parallel to the workbench 13, and multiple upright columns 12 are arranged on the bottom plate 11 to support the workbench 13.

[0090] The vibration device 2 is one of a pneumatic exciter and an electromagnetic exciter and can provide a high-frequency vibration effect. The vibration frequency of the vibration device for the high-temperature vibration test of the specimen is 2 - 5000 Hz. The vibration device 2 is arranged between the bottom plate 11 and the workbench 13.

[0091] The high-temperature environment device 3 includes a cover 31, a heating component 32 fixedly arranged inside the cover 31, and a fixed seat 33 movably connected to the cover 31. The fixed seat 33 is fixedly arranged on the frame 1. Specifically, the fixed seat 33 is fixedly arranged on the workbench 13; when the cover 31 and the fixed seat 33 are connected, a cavity 34 is formed inside the cover 31 and the fixed seat 33, and the main function of the cavity 34 is to provide a high-temperature experimental environment for the specimen. A fixture placement hole 35 is vertically penetrated and opened at the central position of the fixed seat 33; the specimen fixture 4 is detachably arranged in the fixture placement hole 35. The heating component 32 includes a heating wire 321 and a temperature sensor 322. The heating wire 321 is arranged on the inner wall of the cover 31; the temperature sensor 322 is arranged inside the cover 31 to detect the temperature of the cavity 34. The test temperature range of the specimen is 1300 - 1550 °C. The cover 31 and the fixed seat 33 are made of high-temperature resistant materials, and the specific materials can be alumina or high-temperature resistant alloy materials.

[0092] The diameter of the side part of the fixed seat 33 gradually increases from top to bottom to form a stepped side wall, and the open end of the cover 31 has a stepped opening that cooperates with the stepped side wall. When the cover 31 is connected to the fixed seat 33, the contact surface is a bent surface, which can extend the path of external heat dissipation to reduce heat loss in the cavity 34. A high-temperature resistant sealing gasket is provided at the stepped opening of the open end of the cover 31 to improve the sealing effect of the cavity 34.

[0093] The structure of the lifting device 5 is as Figures 6 to 8 shown. The lifting device 5 includes: a bracket 51, a guiding component 52, a linear driving device 53, and a connecting component 54. The bracket 51 is arranged on the frame 1; the linear driving device 53 is arranged on the bracket 51; a part of the connecting component 54 is fixedly connected to the output end of the linear driving device 53, and a part of it is fixedly connected to the outside of the cover 31. Some components of the guiding component 52 are arranged on the bracket, and some components are arranged on the connecting component. The guiding component 52 is used for the connecting component 54 to move linearly stably.

[0094] The linear driving device 53 drives the connecting component 54, thereby making the cover 31 contact or move away from the fixed seat 33. The linear driving device 53 includes, but is not limited to, linear driving elements such as cylinders, oil cylinders, and electric push rods, as long as it can provide linear driving force. The lifting device 5 has two working states:

[0095] In the first working state, the lifting device 5 raises the cover 31 upward so that the cover 31 is in a position away from the fixed seat 33, which is convenient for placing the specimen fixture 4 on the fixed seat 33;

[0096] In the second working state, the lifting device 5 moves the cover 31 downward so that the cover 31 is in contact with the fixed seat 33 to form the cavity 34.

[0097] In some specific embodiments, the lifting device 5 further includes a drag chain 55. One end of the drag chain 55 is arranged on the connecting component 54, and the other end is arranged on the bracket 51.

[0098] Specifically, the guiding component 52 includes: a slide rail 521 and a slider 522. The slide rail 521 is vertically fixed on the bracket 51, and the slider 522 is fixedly connected to the connecting component 54; the slider ⑤22 is slidably connected to the slide rail 521; there are two groups of guiding components 52, which are respectively arranged on the left and right sides of the bracket 51. By providing two guiding components 52, the stability of linear motion is improved.

[0099] Specifically, the connecting component 54 includes: a cover body support plate 541, a connecting plate 542, a sliding connecting plate 543, and a linear drive connecting plate 544. The cover body support plate 541 is circular ring-shaped, and the opening end face of the cover body 31 is fixedly connected to the upper surface of the cover body support plate 541; the connecting plate 542 is arranged on one side of the cover body support plate 541 and perpendicular to the upper surface of the cover body support plate 541; one side of the sliding connecting plate 543 is fixedly connected to the connecting plate 542, and the other side is fixedly connected to the slider 522; and the linear drive connecting plate 544 is an inverted L-shaped plate, including a horizontal portion 544a and a vertical portion 544b. The horizontal portion 544a is fixedly connected to the output end of the linear drive device 53, and the vertical portion 544b is fixedly connected to the top of the sliding connecting plate 543 on the same side as the slider 522.

[0100] The connecting component 54 further includes: a rib plate connecting plate 545, which is fixedly arranged on the side surface of the connecting plate 542; and rib plates 546. There are two rib plates 546, which are respectively arranged on the left and right sides of the cover body 31. One end of the rib plate 546 is fixedly connected to the circumferential outer side surface of the cover body support plate 541, and the other end of the rib plate 546 is fixedly connected to the end of the rib plate connecting plate 545.

[0101] With the structural design of the lifting device 5, the cover body 31 can stably contact or move away from the fixed seat 33.

[0102] The specimen is a strip-shaped specimen 100 or a spring-shaped specimen 200.

[0103] The structure of the specimen fixture 4 is as Figures 9 to 13 shown. The specimen fixture 4 includes a tube body assembly 41, a tube body cap 42, a top cover 43, a sleeve 44, a connecting screw 45, a connecting nut 46, a compensating spring 47, an air inlet connecting piece 48, and a base 49. Specifically, the component structure and connection relationship of the specimen fixture 4 are described as follows:

[0104] The structure of the tube body assembly 41 is as Figure 14 and Figure 15As shown. The tube body assembly 41 includes an outer tube 411 and a central tube 412. The central tube 412 is partially located inside the outer tube 411 and is coaxially arranged with the outer tube 411. The tops of the outer tube 411 and the central tube 412 are flush, and the tops of both are connected by an upper end plate 413. The bottom end of the central tube 412 extends out of the outer tube 411, and the bottom end of the outer tube 411 is connected to the outer side wall of the central tube 412 through a lower end plate 414. A sealing plate 415 is provided at the bottom end of the central tube 412, and the top end of the central tube 412 is open. The space gap between the outer tube 411 and the central tube 412 is a condensation channel 416. A plurality of water pipes 417 are evenly arranged around the central axis in the condensation channel 416. The water pipes 417 penetrate through the lower end plate 414 and extend to the outside of the central tube 412. The water pipes 417 are connected to a water supply cooling device. One end of the water pipe 417 is communicated with the condensation channel 416, and the other end is communicated with the water supply cooling device (the water pipes 417 are divided into inlet pipes and outlet pipes according to the functions of water inlet and outlet, that is, the water pipes 417 arranged on the outer wall of the central tube 412 are divided into inlet pipes and outlet pipes, and they are divided into outlet pipes and inlet pipes according to their connection with the water inlet and outlet of the water supply cooling device. Those skilled in the art can understand that the specific implementation manners will not be elaborated too much).

[0105] The structure of the tube body cap 42 is as Figure 16 and Figure 17 shown. The inside of the tube body cap 42 is a cavity 421. The top end of the outer tube 411 is sleeved inside the cavity 421. The tube body cap 42 is detachably connected to the outer tube 411. The top end surface of the cavity 421 of the tube body cap 42 is spaced from the top end surface of the upper end plate 413. An opening 422 communicating with the cavity 421 is opened at the center position of the upper end of the tube body cap 42. An unpenetrated cap sample placement groove 423 is opened at the top of the upper end of the tube body cap 42. The cap sample placement groove 423 includes a cap long sample placement groove 423a and a cap spring sample placement groove 423b. The cap spring sample placement groove 423b is coaxially opened with the cap opening 422. The cap long sample placement grooves 423a are arranged at intervals along the circumferential direction. In this embodiment, 6 cap long sample placement grooves 423a are provided. The number of the cap long sample placement grooves 423a is not limited in this embodiment. A sleeve placement groove 424 is opened at the top end of the cavity 421 of the tube body cap 42. The sleeve placement groove 424 is coaxially opened with the cap opening 422. An air outlet 425 communicating with the cavity 421 is opened at the upper end of the tube body cap 42.

[0106] The structure of the top end cover 43 is as Figure 18 and Figure 19As shown in the figure. The top cover 43 is spaced above the tube cap 42. A through top cover opening 431 is provided at the center position of the top cover 43. An unthrough end cover long sample placement groove 432 is provided on the lower end surface of the top cover 43, and the end cover long sample placement grooves 432 are arranged at intervals along the circumferential direction; both ends of the long sample 100 are respectively in the cap long sample placement groove 423a and the end cover long sample placement groove 432, as Figure 10 shown; one end of the spring-like sample 200 is in the cap spring sample placement groove 423b, and the other end of the spring-like sample 200 abuts against the lower end surface of the top cover 43, as Figures 11 to 13 shown.

[0107] As Figure 13 shown, the sleeve 44 is arranged in the central tube 412 and is coaxially arranged with the central tube 412. The structure of the sleeve 44 is as Figure 20 shown. The top end of the sleeve 44 is an open end 441, and the open end 441 abuts against the sleeve placement groove 424. The open end 441 of the sleeve 44 and the cap sleeve placement groove 424 form a positioning fit; a sleeve through hole 442 is provided at the bottom end of the sleeve 44. The material of the sleeve 44 can be selected as a high-temperature resistant material. In order to reduce costs, the sleeve 44 can also be made of stainless steel. The length of the sleeve 44 is 40 cm to 60 cm.

[0108] As Figure 21 shown, the connecting screw 45 includes a screw part 451 and a top part 452. The top part 452 is the part at the top of the screw part 451 and is used to apply torque (such as tightening with a wrench). The structure of the top part 452 can include: hexagon head, round head, square head, internal hexagon head, etc. The screw part 451 sequentially passes through the top cover opening 431 of the top cover 43, the cap opening 422 of the tube cap 42, the open end 441 and the sleeve through hole 442 of the sleeve 44 and continues to extend into the inner cavity of the central tube 412; the connecting screw 45 is in clearance fit with the cap opening 422 and the sleeve through hole 442 respectively; the top part 452 abuts against the upper top surface of the top cover 43. The length of the screw part 451 is 140 cm to 170 cm.

[0109] The connecting nut 46 is arranged at one end of the screw part 451 away from the top part 452.

[0110] The upper end of the compensating spring 47 abuts against the bottom end of the sleeve 44, and the lower end abuts against the connecting nut 46. The connecting screw 45 - sleeve 44 - compensating spring 47 - connecting nut 46 form a prestress precise adjustment mechanism. By controlling the axial displacement of the connecting nut 46 to control the compression amount of the compensating spring 47, a precise prestress adjustment range of 5 - 10 N is achieved, which not only ensures the effective clamping of the sample but also avoids the plastic deformation of the spring-like sample 200.

[0111] The intake connection member 48 is provided on the side wall near the bottom end of the central tube 412 and communicates with the central tube 412. A part of the intake connection member 48 is connected to the gas supply device. An intake port 412a is provided on the side wall near the bottom end of the central tube 412, and the intake connection member 48 is disposed on the intake port 412a. The gas supply device includes a gas source, a gas flow meter, and a gas flow control valve that are connected in sequence by pipelines. The inert gas enters the central tube 412 from the intake connection member 48 and flows upward to the sleeve 44. Since the sleeve 44 and the connecting screw 45 are in clearance fit, the gas can enter the inside of the sleeve 44 from the sleeve through-hole 442 and enter the cavity 34 through the air outlet hole 425 of the tube body cap 42.

[0112] The structure of the base 49 is as Figure 22 shown. The sealing plate 415 of the tube body assembly 41 is detachably connected to the base 49, and the sealing plate 415 is threadedly connected or snap-connected to the base 49. The bottom end surface of the base 49 is connected to the vibration device 2. Threaded holes are provided along the circumference of the base 49, and corresponding threaded holes are also provided on the upper surface of the vibration device 2. The base 49 and the vibration device 2 are connected by studs. A water cooling cavity is also provided inside the base 49, and the water cooling cavity is connected to the water supply and cooling device, which can avoid the influence of part of the heat of the specimen fixture 4 on the vibration device 2.

[0113] The tube body cap 42 is detachably connected to the outer sleeve 411, specifically by snap connection, and the tube body cap 42 is connected to the outer sleeve 411 by a clamp; in this embodiment, the tube body cap 42 is threadedly connected to the outer sleeve 411. An external thread is provided on the side wall at the top end of the outer sleeve 411, and an internal thread adapted to the external thread is provided on the side wall of the cavity 421 of the tube body cap 42.

[0114] Furthermore, on the basis of the threaded connection between the tube body cap 42 and the outer sleeve 411, the specimen fixture 4 further includes a fastening assembly for preventing the tube body cap 42 from loosening from the outer sleeve 411; the fastening assembly includes an anti-rotation pin 4a. A first limit hole 426 communicating with the cavity 421 is provided at the center position of the upper end of the tube body cap 42, and an unpenetrated second limit hole 413a is provided on the upper end surface of the upper end plate 413. After the tube body cap 42 is connected to the outer sleeve 411, the first limit hole 426 and the second limit hole 413a are vertically corresponding, and the anti-rotation pin 4a passes through the first limit hole 426 and the second limit hole 413a in sequence. The anti-rotation pin 4a is made of a high-temperature resistant material. The specific material can be selected as silicon carbide material, with a length of 35 mm. The cross-section of the anti-rotation pin 4a can be circular or square, which is not limited in this embodiment. Preferably, it is circular. The circular anti-rotation pin 4a is convenient for processing and forming, and its diameter is 4 mm. The fastening assembly further includes a fastening nut 4b provided at the lower end of the tube body cap 42 and threadedly connected to the outer sleeve 411.

[0115] A water pipe 417 is provided in the specimen fixture 4. The water pipe 417 is connected to the water supply and cooling device, which can maintain a lower temperature inside the central pipe 412 and avoid affecting the performance of the compensation spring 47.

[0116] The pipe body cap 42, the top end cap 43 and the connecting screw 45 are made of high-temperature resistant materials, specifically, they can be made of silicon carbide materials. The outer sleeve 411 and the central pipe 412 can be made of stainless steel materials, which can reduce costs. The compensation spring 47 is a spring made of ordinary materials. The sleeve 44 extends the distance between the compensation spring 47 and the pipe body cap 42, which can reduce the influence of high temperature on the compensation spring 47.

[0117] The specimen vibration fatigue test device in a high-temperature environment further includes a control device (not shown in the figure). The control device is electrically connected to the vibration device 2, the heating assembly 32, the lifting device 5, the water supply and cooling device and the gas supply device respectively to realize the mechanical operation of the equipment. The control device is electrically connected to the vibration device 2 to control the start and stop of the vibration device 2 and adjust the vibration frequency of the vibration device 2. The control device is electrically connected to the heating wire 321 and the temperature sensor 322 of the heating assembly 32 respectively. When the temperature sensor 322 detects that the cavity 34 reaches the preset temperature, the control device controls the heating wire 321 to stop heating; when the temperature sensor 322 detects that the cavity 34 is lower than the preset temperature, the control device controls the heating wire 321 to heat until the temperature of the cavity 34 reaches the preset temperature. The control device is electrically connected to the linear drive device 53 of the lifting device 5, and the linear drive device 53 drives the connecting assembly 54 so that the cover body 31 contacts or separates from the fixed seat 33.

[0118] The usage method of the specimen fixture 4 is as follows:

[0119] Place one end of the specimen in the cap specimen placement groove 423, one end of the strip-shaped specimen 100 in the cap strip-shaped specimen placement groove 423a, and one end of the spring-shaped specimen 200 in the cap spring-shaped specimen placement groove 423b. Place the top cap 43 on the top end of the specimen. Among them, the top end of the strip-shaped specimen 100 is inserted into the end cap strip-shaped specimen placement groove 432, and the other end of the spring-shaped specimen 200 abuts against the lower end face of the top cap 43. This specimen fixture 4 can meet the tests of the strip-shaped specimen 100 and the spring-shaped specimen 200. When in use, only one type of specimen needs to be placed. After clamping the specimen between the tube body cap 42 and the top cap 43, the screw part 451 of the connecting screw 45 sequentially passes through the top cap opening 431 of the top cap 43 and the cap opening 422 of the tube body cap 42. The open end 441 of the sleeve 44 abuts against the sleeve placement groove 424 of the tube body cap 42. The screw part 451 extends out of the sleeve through hole 442. A compensation spring 47 is sleeved on the screw part 451 at the bottom end of the sleeve 44. A connecting nut 46 is screwed on the screw part 451 at the end of the compensation spring 47 away from the sleeve 44. By adjusting the position of the connecting nut 46 on the screw part 451, the pre-stress adjustment of the specimen by the specimen fixture 4 is realized. The pre-stress of the spring-shaped specimen 200 is in the range of 5 - 10 N. Too large pre-stress will damage the spring. After adjusting to the appropriate pre-stress, the tube body cap 42, the top cap 43, the sleeve 44, the connecting screw 45, the connecting nut 46 and the compensation spring 47 are integrally connected and fixed to the tube body assembly 41. Among them, the tube body cap 42 is connected to the outer sleeve tube 411. The sealing plate 415 of the tube body assembly 41 is connected to the base 49. In this way, the assembly of the specimen and the specimen fixture is completed.

[0120] After the bottom end face of the base 49 is connected to the vibration device 2, after the tube body assembly 41, the tube body cap 42, the top cap 43, the sleeve 44, the connecting screw 45, the connecting nut 46, the compensation spring 47 and the specimen are integrally connected, the tube body assembly 41 passes through the fixture placement hole 35, and the sealing plate 415 of the tube body assembly 41 is connected to the base 49. The air inlet connecting piece 48 is installed on the air inlet 412a.

[0121] A specimen vibration fatigue test device in a high-temperature environment provided by the present invention fixes the specimen inside the high-temperature environment device by a specimen fixture, and applies a vibration force to the specimen through the vibration device, so as to conduct a fatigue test on the specimen under the combined effect of high-frequency vibration and high temperature. Compared with the prior art, the present invention improves the application range of the specimen vibration fatigue test device and can conduct a specimen fatigue test on the specimen in a high-temperature, inert gas environment up to 1300 °C - 1600 °C.

[0122] The specimen fixture provided by the embodiment of the present invention has the following advantages:

[0123] (1)Modular multi-sample compatible structure: The sample fixture adopts a collaborative design of a split tube body cap and a top cap. The tube body cap is integrated with a differential sample placement structure, including a cap long sample placement groove that can accommodate long strip samples simultaneously and a cap spring sample placement groove adapted to spring-shaped samples; the top cap is correspondingly provided with an end cap long sample placement groove and a spring end abutting plane, and single-station compatible testing of long strip samples and spring-shaped samples is achieved through selective assembly.

[0124] (2)The connecting screw-sleeve-compensation spring-connecting nut forms a precise prestress adjustment mechanism. The compression amount of the compensation spring is controlled by the axial displacement of the connecting nut, achieving a precise prestress adjustment range of 5-10 N, which not only ensures effective clamping of the sample but also avoids plastic deformation of the spring-shaped sample.

[0125] (3)Multi-directional stable connection system: The geometric fit between the sample end and the differential placement groove; the transitional fit between the open end of the sleeve and the sleeve placement groove; the tube body assembly forms a rigid connection with the base through a sealing plate. These three aspects ensure the axial force stability of the sample during the test.

[0126] (4)Integrated assembly design: Each component is quickly assembled through a standardized interface.

[0127] Finally, it should be noted that the above-described embodiments are only specific implementation manners of the present invention, used to illustrate the technical solutions of the present invention, rather than limiting it. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: Any person skilled in the art within the technical scope disclosed by the present invention can still modify the technical solutions recorded in the foregoing embodiments, or can easily think of changes, or perform equivalent replacements for some of the technical features; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the protection scope of the present invention.

Claims

1. A specimen vibration fatigue test device for high-temperature environment, characterized in that Comprising: A frame; A vibration device, which is inside the frame and is used to apply a vibration force to the specimen during the test; The vibration device is one of a pneumatic shaker and an electromagnetic shaker; A high-temperature environment device, which is on the frame; The high-temperature environment device includes a cover body, a heating component fixedly arranged inside the cover body, and a fixing seat movably connected to the cover body. The fixing seat is fixedly arranged on the frame; when the cover body and the fixing seat are connected, a cavity is formed inside the cover body and the fixing seat; a clamp placement hole is vertically penetrated and opened at the central position of the fixing seat; A specimen clamp, which is detachably arranged in the clamp placement hole and is connected to the vibration device. The specimen clamp is used to place the specimen in the cavity; the specimen clamp corresponds to the vibration device and the high-temperature environment device vertically; A lifting device, which is arranged on the frame. The lifting device is fixedly connected to the outer wall of the cover body and is used to drive the cover body to contact or separate from the fixing seat; and A water supply cooling device and a gas supply device respectively connected to the specimen clamp.

2. The vibration fatigue test device for specimens in a high-temperature environment according to claim 1, wherein The heating component includes: Heating wires, which are arranged on the inner wall of the cover body; A temperature sensor, which is arranged inside the cover body to detect the temperature of the cavity.

3. The specimen vibration fatigue test device for high-temperature environment according to claim 1, wherein, The lifting device includes: A bracket, which is arranged on the frame; A linear driving device, which is arranged on the bracket; and A connecting component, a part of which is fixedly connected to the output end of the linear driving device, and a part of which is fixedly connected to the outside of the cover body; A guiding component, a part of whose components are arranged on the bracket and a part of whose components are arranged on the connecting component; The linear driving device drives the connecting component so that the cover body contacts or separates from the fixing seat.

4. The specimen vibration fatigue test device for high-temperature environment according to claim 3, characterized in that, The lifting device further includes: A drag chain, one end of which is arranged on the connecting component and the other end of which is arranged on the bracket.

5. The specimen vibration fatigue test device for high-temperature environment according to claim 3, wherein The guiding component includes: A slide rail, which is vertically fixedly arranged on the bracket; and A slider, which is slidably connected to the slide rail and is fixedly connected to the connecting component; There are two groups of guiding components, which are respectively arranged on the left and right sides of the bracket.

6. The specimen vibration fatigue test device for high-temperature environment according to claim 5, wherein, The connecting component includes: A cover body support plate, which is circular. The open end face of the cover body is fixedly connected to the upper surface of the cover body support plate; A connecting plate, which is arranged on one side of the cover body support plate and is perpendicular to the upper surface of the cover body support plate; A sliding connecting plate, one side of which is fixedly connected to the connecting plate and the other side of which is fixedly connected to the slider; and A linear driving connecting plate, which is an inverted L-shaped plate and includes a horizontal part and a vertical part. The horizontal part is fixedly connected to the output end of the linear driving device, and the vertical part is fixedly connected to the top of the sliding connecting plate on the same side as the slider.

7. The vibration fatigue test device for specimens in a high-temperature environment according to claim 1, characterized in that, The specimen is a strip-shaped specimen or a spring-shaped specimen; The specimen clamp includes: A pipe body component, which includes an outer sleeve pipe and a central pipe. The central pipe is partially located inside the outer sleeve pipe and is coaxially arranged with the outer sleeve pipe; the top ends of the outer sleeve pipe and the central pipe are flush, and the top ends of both are connected by an upper end plate; the bottom end of the central pipe extends out of the outer sleeve pipe, and the end of the outer sleeve pipe and the central pipe are hermetically connected. The top end of the central pipe is open; the bottom end of the central pipe is closed; the space gap between the outer sleeve pipe and the central pipe is a condensation channel, and multiple water pipes are uniformly arranged around the central axis in the condensation channel. The water pipes penetrate through the lower end plate and extend to the outside of the central pipe, and the water pipes are connected to the water supply cooling device; The tube body cap has a cavity inside. The top end of the outer sleeve is sleeved in the cavity. The tube body cap is detachably connected to the outer sleeve. The top end face of the cavity of the tube body cap is spaced from the top end face of the upper end plate. An opening is provided at the center of the upper end of the tube body cap and is communicated with the cavity. An unpenetrated cap specimen placement groove is provided at the top of the upper end of the tube body cap. The cap specimen placement groove includes a cap long specimen placement groove and a cap spring specimen placement groove. A sleeve placement groove is provided at the top end of the cavity of the tube body cap. An air vent is provided at the upper end of the tube body cap and is communicated with the cavity. The top end cap is spaced above the tube body cap. A penetrated top end cap opening is provided at the center of the top end cap. An unpenetrated end cap long specimen placement groove is provided on the lower end face of the top end cap. The two ends of the long strip specimen are respectively in the cap long specimen placement groove and the end cap long specimen placement groove. One end of the spring specimen is in the cap spring specimen placement groove, and the other end of the spring specimen abuts against the lower end face of the top end cap. The sleeve is arranged in the central tube and coaxially with the central tube. The top end of the sleeve is an open end, and the open end abuts in the sleeve placement groove. A sleeve through hole is provided at the bottom end of the sleeve. The connecting screw, the screw part of the connecting screw sequentially passes through the top end cap opening of the top end cap, the cap opening of the tube body cap and the sleeve and continues to extend into the inner cavity of the central tube. The connecting screw is in clearance fit with the cap opening and the sleeve through hole respectively. The top end part of the connecting screw abuts against the upper top face of the top end cap. The connecting nut is arranged at one end of the screw part far from the top end part. The compensating spring, its upper end abuts against the bottom end of the sleeve, and its lower end abuts against the connecting nut. The air inlet connecting piece is arranged on the side wall near the bottom end of the central tube and is communicated with the central tube. Part of the air inlet connecting piece is connected to the air supply device; and The base, the sealing plate of the tube body assembly is detachably connected to the base, and the bottom end face of the base is connected to the vibration device.

8. The vibration fatigue test device for specimens in a high-temperature environment according to claim 7, characterized in that, External threads are provided on the side wall of the top end of the outer sleeve, and internal threads adapted to the external threads are provided on the side wall of the cavity of the tube body cap. The tube body cap is threadedly connected to the outer sleeve.

9. The vibration fatigue test device for specimens in a high-temperature environment according to claim 8, characterized in that The specimen fixture further includes a fastening assembly for preventing the tube body cap and the outer sleeve from loosening. The fastening assembly includes an anti-rotation pin. A first limiting hole communicated with the cavity is provided at the center of the upper end of the tube body cap. An unpenetrated second limiting hole is provided on the upper end face of the upper end plate. After the tube body cap is connected to the outer sleeve, the first limiting hole and the second limiting hole are vertically corresponding, and the anti-rotation pin sequentially passes through the first limiting hole and the second limiting hole. The fastening assembly further includes a fastening nut arranged at the lower end of the tube body cap and threadedly connected to the outer sleeve.

10. The specimen vibration fatigue test device for high-temperature environment according to claim 1, characterized in that, It further includes: The control device is electrically connected to the vibration device, the heating assembly, the lifting device, the water supply and cooling device and the air supply device respectively.

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