Wide-spectrum large-load high-efficiency high-resolution in-situ fatigue three-dimensional imaging device and test method

Abstract

The invention belongs to the technical field of advanced material testing, and particularly relates to an in-situ fatigue three-dimensional imaging device with wide frequency spectrum, large load, high efficiency and high resolution and a testing method. The device mainly comprises an oil source, a controller, a computer, oil pipes, a data transmission line and a host, the host is arranged inside or outside the X-ray three-dimensional imaging instrument, the oil source conveys hydraulic oil to a static pressure actuator cylinder body of a static pressure actuator assembly on the host through the two sets of oil pipes, and the controller is connected with the computer through a line. And the controller controls the load and displacement of the host during the fatigue test through the data transmission line. The overall design overcomes the defects that an existing device is large in weight, large in size, narrow in frequency spectrum, small in load, low in efficiency, low in resolution ratio, poor in adaptability and the like, and eliminates adverse effects of an in-situ high-frequency fatigue experiment and an in-situ high-cycle fatigue experiment on an X-ray three-dimensional imaging instrument. And the convenience, usability and three-dimensional image quality of an in-situ fatigue three-dimensional imaging experiment are greatly improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of advanced material testing, and in particular relates to an in-situ fatigue three-dimensional imaging device and a testing method with wide spectrum, large load, high efficiency and high resolution. Background Art

[0002] Fatigue failure refers to the phenomenon that cracks propagate under cyclic loads and lead to failure of materials. It is one of the basic modes of material failure. Fatigue fracture occurs when there are many strain cycles, such as mechanical structures, high-speed rotating shafts, and automobile wheels. Once fatigue failure occurs in key materials and components, it will lead to major accidents such as train derailment, tower crane breakage, and plane crashes. Therefore, mastering the laws of fatigue crack nucleation and propagation and being able to predict fatigue life are of great significance to protecting national property and people's lives.

[0003] Traditional fatigue research methods mainly use large mechanical testing machines to load samples with cyclic loads. After unloading, fatigue cracks are observed using metallographic microscopes, scanning electron microscopes, etc. to obtain sample surface information, but it is impossible to study the inside of the sample. In recent years, combining in-situ fatigue devices and three-dimensional imaging devices (synchrotron radiation light source imaging beamlines, large industrial CT, etc.) to obtain internal sample information and conduct in-situ research has become a new direction in fatigue research.

[0004] However, the existing combination has many disadvantages. The existing in-situ fatigue devices generally have disadvantages such as heavy weight, large size, limited available frequency, and low load. As far as the three-dimensional imaging device is concerned, the machine time available at the synchrotron radiation light source imaging line station is limited, and it is generally difficult to apply for machine time. Even if the machine time is applied for, it is basically only one or two days. Such a short time is not enough for fatigue research. The resolution of large-scale industrial CT is very limited, generally in the order of hundreds of microns, and the slightly better ones are in the order of tens of microns. With such a low resolution, fatigue research cannot be carried out. In order to achieve high-resolution imaging for micron CT based on projection architecture, the sample must be close to the radiation source, but the existing in-situ fatigue device itself is large in size, and it is difficult to obtain high-resolution fatigue imaging results when combined with the micron CT based on projection architecture. Therefore, various combinations of existing in-situ fatigue devices and three-dimensional imaging devices cannot meet the increasing demand for fatigue research.

[0005] In summary, the existing in-situ fatigue three-dimensional imaging devices have the disadvantages of limited machine time, low resolution, narrow spectrum, low load, low efficiency, heavy weight and large size. It is urgent to develop a set of in-situ fatigue three-dimensional imaging devices that can achieve wide spectrum, large load, high efficiency and high resolution, and establish relevant testing methods to provide a new technical means for simultaneously obtaining surface information, internal information and evolution information in the material fatigue process, thereby helping to grasp the fatigue deformation and fracture mechanism, establish a fatigue life prediction model, and ensure the safety of key materials and components in important fields. Summary of the invention

[0006] The technical problem solved by the present invention is to provide an in-situ fatigue three-dimensional imaging device and testing method with a wide spectrum, large load, high efficiency and high resolution, so as to solve the problems of heavy weight, large size, low efficiency, low resolution, narrow spectrum and low load in the prior art, and provide a usable, easy-to-use and convenient technical means for studying the nucleation, extension and evolution of fatigue cracks.

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

[0008] A wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device, the device mainly comprises: an oil source, a controller, a computer, an oil pipe, a data transmission line, and a host. The host is arranged inside or outside an X-ray three-dimensional imaging instrument. The device is provided with two sets of oil pipes: an internal oil pipe and an external oil pipe. One end of the internal oil pipe is connected to the oil source, and the other end of the internal oil pipe is extended to the inside of the X-ray three-dimensional imaging instrument for use. One end of the external oil pipe is connected to the oil source, and the other end of the external oil pipe is used outside the X-ray three-dimensional imaging instrument. The oil source transports hydraulic oil to the static pressure actuator cylinder of the static pressure actuator assembly on the host through the two sets of oil pipes respectively; the device is provided with two sets of data transmission lines: an internal data transmission line and an external data transmission line. One end of the internal data transmission line is connected to the output end of the controller, and the other end of the internal data transmission line is extended to the inside of the X-ray three-dimensional imaging instrument and connected to the servo valve on the host. One end of the external data transmission line is connected to the output end of the controller, and the other end of the external data transmission line is connected to the servo valve on the host outside the X-ray three-dimensional imaging instrument. The controller is connected to the computer through a line, and the controller controls the load and displacement of the host during fatigue test through the data transmission line.

[0009] The wide-spectrum, large-load, high-efficiency, and high-resolution in-situ fatigue three-dimensional imaging device comprises a main body including a base, a bearing frame, a static pressure actuator assembly, a guide assembly, a lower clamp assembly, and an upper clamp assembly. The bottom of the bearing frame is detachably mounted on the base. The bearing frame is a split structure, including an upper bearing frame, a middle bearing frame, and a lower bearing frame. The upper bearing frame, the middle bearing frame, and the lower bearing frame are fixedly connected in sequence from top to bottom. The top of the upper bearing frame is connected to the upper clamp body of the upper clamp assembly by screws. The middle and lower parts of the upper bearing frame are bearing The bearing cylinder is connected to the middle bearing frame by fastening screws to ensure that the upper fixture assembly remains stationary during fatigue testing; the specimen is installed between the upper fixture body of the upper fixture assembly and the lower fixture body of the lower fixture assembly on the inner side of the bearing cylinder, and the guide assembly is installed on the inner side of the middle bearing frame of the bearing frame to ensure that the lower fixture assembly moves linearly relative to the upper fixture assembly. The lower bearing frame also serves as the static pressure actuator cylinder of the static pressure actuator assembly. The static pressure actuator assembly is used to drive the lower fixture assembly to perform fatigue dynamic motion. The fatigue frequency range is: 0.01Hz to 300Hz.

[0010] The wide-spectrum, large-load, high-efficiency, and high-resolution in-situ fatigue three-dimensional imaging device, the hydrostatic actuator assembly includes a piston rod, a hydrostatic actuator cylinder, a cylinder lower cylinder head, a cylinder upper cylinder head and a piston, the inner cavity of the hydrostatic actuator cylinder is equipped with a piston rod, a cylinder lower cylinder head, a cylinder upper cylinder head and a piston, the upper and lower parts of the piston rod are respectively penetrated through the cylinder upper cylinder head and the cylinder lower cylinder head and are slidably matched, and a piston is provided in the middle of the piston rod, which is slidably matched with the inner cavity of the hydrostatic actuator cylinder; the servo valve on the outer side of the lower bearing frame is communicated with the inner cavity of the hydrostatic actuator cylinder located above and below the piston through the internal oil inlet channel and the oil return channel of the lower bearing frame, respectively, so that the hydraulic oil is reciprocatedly fed and returned at the upper and lower ends of the piston to push the piston rod to move up and down.

[0011] The wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device, the guide assembly includes a sensor connecting plate, a guide rail connecting plate, a slider, a guide rail, a load sensor, and a transition plate. The sensor connecting plate is connected to the upper end of the piston rod, and the bottom and both sides of the guide rail connecting plate are respectively connected to the sensor connecting plate and the slider. The two guide rails are symmetrically installed on the inner side wall of the middle load-bearing frame. The two sides of the guide rail connecting plate correspond to the guide rails through the slider and are in sliding cooperation to ensure that the piston rod moves in a straight line during the up and down movement without rotation; the lower end of the load sensor is connected to the sensor connecting plate, and the upper end of the load sensor is connected to the transition plate.

[0012] The described wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device, the lower fixture assembly includes a lower fixture body, a lower gasket, a specimen lower pressure plate, and a lower clamping screw. The lower fixture assembly is installed on the transition plate of the guide assembly through the lower fixture body, and the lower part of the specimen is inserted into the lower fixture body. The lower gasket used for specimen adjustment is installed in the lower fixture body and is located on one side of the lower part of the specimen. A specimen lower pressure plate is arranged on the other side of the lower part of the specimen. The lower clamping screw passes through the specimen lower pressure plate to clamp and fix the lower part of the specimen; the upper fixture assembly includes an upper fixture body, an upper gasket, a specimen upper pressure plate, and an upper clamping screw. The upper fixture assembly is fixed to the upper load-bearing frame by screws, and the upper part of the specimen is inserted into the upper fixture body. The upper gasket is installed in the upper fixture body and is located on one side of the upper part of the specimen. A specimen upper pressure plate is arranged on the other side of the upper part of the specimen. The upper clamping screw passes through the specimen upper pressure plate to clamp and fix the upper part of the specimen.

[0013] The wide-spectrum, large-load, high-efficiency, and high-resolution in-situ fatigue three-dimensional imaging device has a top through hole on the top of the upper bearing frame, an upper through hole on the upper fixture body, and a lower through hole on the lower fixture body that are coaxially corresponding one to one, and a guide rod passes through the top through hole, the upper through hole, and the lower through hole in sequence; when in use, the upper bearing frame is removed independently as needed: first, the guide rod is inserted into the upper through hole, the lower through hole, and the top through hole to connect the lower fixture body and the upper fixture body; then, the fastening screws and screws are removed, and the upper bearing frame is removed.

[0014] The host specifications of the wide-spectrum, large-load, high-efficiency and high-resolution in-situ fatigue three-dimensional imaging device are as follows: outer diameter ≤100mm, height ≤240mm, weight ≤8kg; when the host is set outside the X-ray three-dimensional imaging instrument, the host is directly placed on the experimental platform through the base; when the host is set inside the X-ray three-dimensional imaging instrument, the host is fixedly installed on the turntable of the X-ray three-dimensional imaging instrument through the base.

[0015] The material of the bearing tube of the in-situ fatigue three-dimensional imaging device with wide spectrum, large load, high efficiency and high resolution is carbon fiber material, engineering plastic, organic glass or metal material.

[0016] The wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging test method comprises the following steps:

[0017] Step 1: Select the X-ray 3D imaging instrument according to your needs;

[0018] Step 2: Install the host on the turntable of the X-ray three-dimensional imaging instrument. The host is fixedly connected to the turntable through the base 1 with screws. The host is fixed with three locking screws at equal intervals in the circumferential direction, and the oil pipe and data transmission line inside the X-ray three-dimensional imaging instrument are connected;

[0019] Step 3: Start the controller, power on the oil source, press the reset button, and start the oil source;

[0020] Step 4: Before installing the specimen, move the piston rod of the static pressure actuator assembly upward until it approaches the upper limit position;

[0021] Step 5: First insert the guide rods into the upper through hole, the lower through hole and the top through hole, remove the upper bearing frame, put the upper gasket into the upper fixture body, put the lower gasket into the lower fixture body, put the fatigue specimen in, put both ends of the specimen completely into the upper fixture body and the lower fixture body, press them with the upper and lower specimen pressing plates respectively, and fix them with the upper and lower pressing screws;

[0022] Step 6: Install the upper bearing frame, fix it with screws and fastening screws, and pull out the guide rods;

[0023] Step 7: Use an X-ray three-dimensional imaging instrument to perform three-dimensional scanning, three-dimensional reconstruction and three-dimensional visualization on the sample to obtain the three-dimensional information of the sample before loading;

[0024] Step 8: In the in-situ test software interface of the computer, set the specimen shape, loading type, control direction, control method, number of cycles, and start the fatigue test;

[0025] Step 9: After the fatigue test reaches the target number of cycles, the fatigue test is paused or ended;

[0026] Step 10: Perform tensile load-keeping control on the sample, and use an X-ray three-dimensional imaging instrument to perform three-dimensional scanning, three-dimensional reconstruction, and three-dimensional visualization on the sample to obtain three-dimensional information of the sample at a specific number of fatigue loading cycles;

[0027] Step 11: After the scan is completed, continue the fatigue test and repeat steps 9 to 10 until the experimental purpose is achieved;

[0028] Step 12: After completing the experimental purpose, unload the force to zero, insert the guide rod, remove the screws and fastening screws, remove the upper load-bearing frame, remove the clamping screws and the specimen clamp, remove the specimen, and turn off the in-situ test software, computer, oil source and controller in turn.

[0029] The wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging test method selects the second test process according to the needs, including the following steps:

[0030] Step 13: Repeat steps 1 to 7;

[0031] Step 14: Turn off the oil source and controller, unplug the oil pipe and data cable inside the X-ray 3D imaging instrument, remove the host from the turntable, place the host on the experimental platform outside the X-ray 3D imaging instrument, and connect the oil pipe and data transmission cable outside the X-ray 3D imaging instrument;

[0032] Step 15: Start the controller and the oil source, repeat steps 8 to 9, unload the force to zero, turn off the oil source and the controller, and unplug the oil pipe and data transmission line outside the X-ray three-dimensional imaging instrument;

[0033] Step 16: Install the host after step 15 on the upper part of the turntable of the X-ray three-dimensional imaging instrument. The host is fixedly connected to the turntable through the base with screws. The host is fixed with three locking screws at equal intervals in the circumferential direction, and the oil pipe and data transmission line inside the X-ray three-dimensional imaging instrument are connected;

[0034] Step 17: Repeat step 10;

[0035] Step 18: Repeat steps 14 to 17 until the experimental purpose is completed, then repeat step 12.

[0036] The design concept of the present invention is:

[0037] In response to the fatigue research needs of mining and mastering internal information and evolution information, the present invention miniaturizes the traditional large-scale fatigue mechanical testing machine and integrates it with an X-ray three-dimensional imaging instrument. In view of the problems of existing devices such as large size, heavy weight, low efficiency, low resolution, poor adaptability, narrow spectrum, and low load, an in-situ fatigue three-dimensional imaging device and testing method with wide spectrum, large load, high efficiency and high resolution is invented, which provides convenient, fast and easy-to-use technical means for studying difficult scientific problems such as fatigue crack nucleation location, crack propagation mechanism, and fatigue model deviation from reality.

[0038] The advantages and beneficial effects of the present invention are:

[0039] 1. The sample stage of the X-ray 3D imaging instrument has a load limit, and the load limits of the sample stages of different X-ray 3D imaging instruments are also different, and some can only load 10kg. The main unit of the in-situ fatigue 3D imaging device of the present invention has a low weight and wide applicability, and can be used in a variety of X-ray 3D imaging instruments.

[0040] 2. The internal space of X-ray 3D imaging instruments is limited, and the light flux is inversely proportional to the distance. The shorter the distance between the ray source and the detector, the higher the light flux, the higher the imaging efficiency and image quality. Therefore, the smaller the host size, the better. The host outer diameter of the in-situ fatigue 3D imaging device of the present invention can be ≤100mm and the height ≤240mm. It has the smallest size and the highest integration among similar devices, which is very conducive to obtaining high-quality in-situ fatigue 3D imaging results.

[0041] 3. The influence of vibration is very large during fatigue experiments. The higher the frequency, the greater the vibration, which has an adverse effect on the sample stage and other components of the X-ray three-dimensional imaging instrument, and even accelerates its failure process. The in-situ fatigue three-dimensional imaging device of the present invention is equipped with two sets of oil pipes and two sets of data transmission lines. During high-frequency fatigue experiments, the experimental process of steps 13 to 18 can be adopted to avoid the influence of vibration caused by high frequency. In addition, for high-cycle fatigue and ultra-high-cycle fatigue, the experimental time may be several weeks or even months; the three-dimensional scanning task of the X-ray three-dimensional imaging instrument is generally heavy, and it is impossible to take out several weeks or even months to do a fatigue experiment; the in-situ fatigue three-dimensional imaging device of the present invention is equipped with two sets of oil pipes and two sets of data transmission lines. During high-cycle fatigue experiments, the experimental process of steps 13 to 18 can be adopted, and it can flexibly switch between ordinary three-dimensional imaging experiments and in-situ fatigue three-dimensional imaging experiments, which does not delay the normal experimental tasks of the X-ray three-dimensional imaging instrument and ensures the smooth progress of the in-situ fatigue three-dimensional imaging experiment.

[0042] 4. The fatigue frequency range of the in-situ fatigue three-dimensional imaging device of the present invention is 0.01 Hz to 300 Hz, and the maximum load is 15 kN, which can meet the fatigue research needs of various metals, ceramics, composite materials, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram of the overall structure of the in-situ fatigue three-dimensional imaging device according to an embodiment of the present invention.

[0044] Figure 2 It is a schematic diagram of the overall structure of the mainframe of the in-situ fatigue three-dimensional imaging device according to an embodiment of the present invention.

[0045] Figure 3 Schematic diagram of the structure of a static pressure actuator assembly according to an embodiment of the present invention.

[0046] Figure 4 It is a schematic diagram of the structure of the guide assembly according to an embodiment of the present invention.

[0047] Figure 5 Schematic diagram of the structure of the upper and lower clamp components according to an embodiment of the present invention.

[0048] Figure 6 Schematic diagram of the sample installation structure of an embodiment of the present invention.

[0049] In the figure, 1 is a base, 2 is a bearing frame (21 is a lower bearing frame, 22 is a middle bearing frame, 23 is an upper bearing frame, 24 is a bearing cylinder), 3 is a static pressure actuator assembly (31 is a piston rod, 32 is a lower cylinder head of a cylinder body, 33 is an upper cylinder head of a cylinder body, 34 is a piston), 4 is a guide assembly (41 is a sensor connecting plate, 42 is a guide rail connecting plate, 43 is a slider, 44 is a guide rail, 45 is a load sensor, 46 is a transition plate), 5 is a lower fixture assembly (51 is a lower fixture body, 52 is a lower gasket, 53 is a specimen lower pressure plate, 54 is a lower clamping screw), 6 is an upper fixture assembly (61 is an upper fixture body, 62 is an upper gasket, 63 is a specimen upper pressure plate, 64 is an upper clamping screw), 7 is a servo valve, 8 is a screw, 9 is a specimen, 10 is a fastening screw, 11 is a guide rod, 12 is an upper through hole, 13 is a lower through hole, and 14 is a top through hole. DETAILED DESCRIPTION

[0050] In order to make the technical problems, technical solutions and advantages to be solved by the present invention clearer, the following will be described in detail with reference to the accompanying drawings and specific embodiments. For the detailed description of these embodiments, it should be understood that those skilled in the art can practice through the present invention and can change and / or modify the illustrated examples by using other embodiments without departing from the spirit of the claims and the principles of the present invention. In addition, although the specific features of the present invention are disclosed in the embodiments, such specific features can be appropriately modified to achieve the functions of the present invention.

[0051] The invention provides an in-situ fatigue three-dimensional imaging device and a testing method with wide spectrum, large load, high efficiency and high resolution.

[0052] like Figure 1 As shown, a wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device, the overall structure of which includes an oil source, a controller, a computer, an oil pipe, a data transmission line, and a host. The host is arranged inside or outside the X-ray three-dimensional imaging instrument. The device is provided with two sets of oil pipes: an internal oil pipe and an external oil pipe. One end of the internal oil pipe is connected to the oil source, and the other end of the internal oil pipe is extended to the inside of the X-ray three-dimensional imaging instrument for use. One end of the external oil pipe is connected to the oil source, and the other end of the external oil pipe is used outside the X-ray three-dimensional imaging instrument. The oil source transports hydraulic oil to the static pressure actuator cylinder of the static pressure actuator assembly on the host through the two sets of oil pipes. The device is provided with two sets of data transmission lines: an internal data transmission line and an external data transmission line. One end of the internal data transmission line is connected to the output end of the controller, and the other end of the internal data transmission line is extended to the inside of the X-ray three-dimensional imaging instrument and connected to the servo valve on the host. One end of the external data transmission line is connected to the output end of the controller, and the other end of the external data transmission line is connected to the servo valve on the host outside the X-ray three-dimensional imaging instrument. The controller is connected to the computer through a line, and the controller controls the load and displacement of the host during fatigue test through the data transmission line.

[0053] like Figure 2 As shown, the overall structure of the mainframe of the in-situ fatigue three-dimensional imaging device includes a base 1, a bearing frame 2, a static pressure actuator assembly 3, a guide assembly 4, a lower clamp assembly 5, and an upper clamp assembly 6. The mainframe structure is very compact and highly integrated. The outer diameter of the mainframe can be ≤100mm, the height ≤240mm, and the weight is light ≤8kg.

[0054] like Figure 1 , Figure 2 and Figure 6 As shown, when the host is arranged outside the X-ray three-dimensional imaging instrument, the host is directly placed on the experimental platform through the base 1. When the host is arranged inside the X-ray three-dimensional imaging instrument, the host is fixedly installed on the turntable of the X-ray three-dimensional imaging instrument through the base 1, and the bottom of the bearing frame 2 is detachably installed with the base 1. The bearing frame 2 is a split structure, including an upper bearing frame 23, a middle bearing frame 22, and a lower bearing frame 21. The upper bearing frame 23, the middle bearing frame 22, and the lower bearing frame 21 are fixedly connected in sequence from top to bottom. The top of the upper bearing frame 23 is connected to the upper clamp body 61 of the upper clamp assembly 6 by screws 8, and the middle and lower parts of the upper bearing frame 23 are the bearing tube 24, which is connected to the middle bearing frame 22 by fastening screws 10 to ensure that the upper clamp assembly 6 is stationary during fatigue testing. The sample 9 is installed between the upper fixture body 61 and the lower fixture body 51 inside the bearing tube 24. The top through hole 14 opened on the top of the upper bearing frame 23, the upper through hole 12 opened on the upper fixture body 61, and the lower through hole 13 opened on the lower fixture body 51 are coaxially corresponding to each other. The guide rod 11 can pass through the top through hole 14, the upper through hole 12, and the lower through hole 13 in sequence. The upper bearing frame 23 can be removed independently. First, the guide rod 11 is inserted into the upper through hole 12, the lower through hole 13, and the top through hole 14, the lower fixture body 51 and the upper fixture body 61 are connected, and then the fastening screws 10 and the screws 8 are removed to remove the upper bearing frame 23. The material of the bearing tube 24 can be carbon fiber material, engineering plastics, organic glass, and metal material.

[0055] The static pressure actuator assembly 3 is used to drive the lower fixture assembly to perform fatigue dynamic motion, and the fatigue frequency range is: 0.01Hz to 300Hz. Figure 3As shown, the hydrostatic actuator assembly 3 includes a piston rod 31, a hydrostatic actuator cylinder, a lower cylinder head 32, an upper cylinder head 33 and a piston 34. The lower supporting frame 21 also serves as the hydrostatic actuator cylinder. The inner cavity of the hydrostatic actuator cylinder is equipped with the piston rod 31, the lower cylinder head 32, the upper cylinder head 33 and the piston 34. The upper and lower parts of the piston rod 31 are respectively penetrated through the upper cylinder head 33 and the lower cylinder head 32 of the cylinder and are slidably matched. The middle part of the piston rod 31 is provided with a piston 34 that is slidably matched with the inner cavity of the hydrostatic actuator cylinder. The servo valve 7 on the outer side of the lower supporting frame 21 is connected to the inner cavity of the hydrostatic actuator cylinder located above and below the piston 34 through the internal oil inlet channel and the return oil channel of the lower supporting frame 21, respectively, so that the hydraulic oil is reciprocated at the upper and lower ends of the piston 34 to push the piston rod to move up and down.

[0056] like Figure 4 As shown, the guide assembly 4 is installed on the inner side of the middle load-bearing frame 22 of the load-bearing frame 2, and includes a sensor connecting plate 41, a guide rail connecting plate 42, a slider 43, a guide rail 44, a load sensor 45, and a transition plate 46. The sensor connecting plate 41 is connected to the upper end of the piston rod 31, and the bottom and both sides of the guide rail connecting plate 42 are respectively connected to the sensor connecting plate 41 and the slider 43. The two guide rails 44 are symmetrically installed on the inner side wall of the middle load-bearing frame 22 of the load-bearing frame 2, and the two sides of the guide rail connecting plate 42 correspond to the guide rails 44 through the slider 43 and are in sliding cooperation, ensuring that the piston rod 31 moves in a straight line during the up and down movement without rotation; the lower end of the load sensor 45 is connected to the sensor connecting plate 41, and the upper end of the load sensor 45 is connected to the transition plate 46.

[0057] like Figure 2 , Figure 4 and Figure 5 As shown, the lower clamp assembly 5 includes a lower clamp body 51, a lower gasket 52, a sample lower pressure plate 53, and a lower clamping screw 54. The lower clamp assembly 5 is installed on the transition plate 46 of the guide assembly 4 through the lower clamp body 51. The lower part of the sample 9 is inserted into the lower clamp body 51. The lower gasket 52 used for adjusting the sample 9 is installed in the lower clamp body 51 and is located on one side of the lower part of the sample 9. The sample lower pressure plate 53 is set on the other side of the lower part of the sample 9. The lower clamping screw 54 passes through the sample lower pressure plate 53 to clamp and fix the lower part of the sample 9.

[0058] The upper clamp assembly 6 includes an upper clamp body 61, an upper gasket 62, a sample upper pressure plate 63, and an upper clamping screw 64. The upper clamp assembly 6 is fixed to the upper supporting frame 23 by screws 8. The upper part of the sample 9 is inserted into the upper clamp body 61. The upper gasket 62 is installed in the upper clamp body 61 and is located on one side of the upper part of the sample 9. The sample upper pressure plate 63 is set on the other side of the upper part of the sample 9. The upper clamping screw 64 passes through the sample upper pressure plate 63 to clamp and fix the upper part of the sample 9.

[0059] Below, the present invention is further described in detail by examples.

[0060] Embodiment 1:

[0061] like Figure 1 to Figure 6 As shown, in this embodiment, a test method of a wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device is as follows:

[0062] Step 1: Select the X-ray 3D imaging instrument XradiaVersaXRM-500 (produced by ZEISS, Germany) according to your needs;

[0063] Step 2: Install the host on the turntable of the X-ray three-dimensional imaging instrument. The host is fixedly connected to the turntable through the base 1 with screws. The host is fixed with three locking screws at equal intervals in the circumferential direction, and the oil pipe and data transmission line inside the X-ray three-dimensional imaging instrument are connected;

[0064] Step 3: Start the controller, power on the oil source, press the reset button, and start the oil source;

[0065] Step 4: Before installing the sample 9, move the piston rod 31 of the static pressure actuator assembly 3 upward until it approaches the upper limit position;

[0066] Step 5: First, insert the guide rod 11 into the upper through hole 12, the lower through hole 13 and the top through hole 14, remove the upper bearing frame 23, put the upper gasket 62 into the upper fixture body 61, put the lower gasket 52 into the lower fixture body 51, put the 0Cr18Ni9 steel fatigue specimen, put both ends of the specimen 9 completely into the upper fixture body 61 and the lower fixture body 51, press them with the specimen upper pressing plate 63 and the specimen lower pressing plate 53 respectively, and fix them with the upper clamping screw 64 and the lower clamping screw 54;

[0067] Step 6: Install the upper bearing frame 23, fix it with screws 8 and fastening screws 10, and pull out the guide rod 11;

[0068] Step 7: Use XradiaVersaXRM-500 to perform 3D scanning, 3D reconstruction, and 3D visualization on sample 9 to obtain 3D information of the sample before loading;

[0069] Step 8: In the in-situ test software interface of the computer, set the sample shape to plate, the loading type to cycle control, the loading frequency to 60Hz, the control mode to displacement control, the control direction to tension, and the number of cycles to 10. 5 Wait, start the experiment;

[0070] Step 9: Experiment reaches cycle number 10 3 When , pause the experiment;

[0071] Step 10: Perform 400N tensile load holding control on sample 9, and use Xradia VersaXRM-500 to perform 3D scanning, 3D reconstruction, and 3D visualization on the sample to obtain 3D information of the sample with a specific number of fatigue loading cycles;

[0072] Step 11: After the scanning is completed, the fatigue test is continued. When the next set number of cycles is reached, the test is paused and step 10 is repeated until the three-dimensional scanning of multiple specific cycle stages is completed to obtain the experimental results;

[0073] Step 12: After completing the experimental purpose, unload the force to zero, insert the guide rod 11, remove the screw 8 and the fastening screw 10, remove the upper supporting frame 23, remove the clamping screws (upper clamping screw 64 and lower clamping screw 54) and the sample pressing plate (sample upper pressing plate 63 and sample lower pressing plate 53), take out the sample 9, and turn off the software, computer, oil source and controller in turn.

[0074] Embodiment 2:

[0075] like Figure 1 to Figure 6 As shown, in this embodiment, a test method of a wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device is as follows:

[0076] Step 1: According to the requirements, select nanoVoxel-3000 (produced by Tianjin Sanying Precision Instrument Co., Ltd.) as the X-ray 3D imaging instrument;

[0077] Step 2: Install the host on the turntable of the X-ray three-dimensional imaging instrument. The host is fixedly connected to the turntable through the base 1 with screws. The host is fixed with three locking screws at equal intervals in the circumferential direction, and the oil pipe and data transmission line inside the X-ray three-dimensional imaging instrument are connected;

[0078] Step 3: Start the controller, power on the oil source, press the reset button, and start the oil source;

[0079] Step 4: Before installing the sample, move the piston rod 31 of the static pressure actuator assembly 3 upward until it approaches the upper limit position;

[0080] Step 5: first insert the guide rod 11 into the upper through hole 12, the lower through hole 13 and the top through hole 14, remove the upper bearing frame 23, put the upper gasket 62 into the upper fixture body 61, put the lower gasket 52 into the lower fixture body 51, put in the fatigue specimen of the single crystal high-temperature alloy DD33, put both ends of the specimen 9 completely into the upper fixture body 61 and the lower fixture body 51, press them with the specimen upper pressing plate 63 and the specimen lower pressing plate 53 respectively, and fix them with the upper clamping screw 64 and the lower clamping screw 54;

[0081] Step 6: Install the upper bearing frame 23, fix it with screws 8 and fastening screws 10, and pull out the guide rod 11;

[0082] Step 7: Use nanoVoxel-3000 to perform 3D scanning, 3D reconstruction and 3D visualization on the sample to obtain the 3D information of the sample before loading;

[0083] Step 8: Turn off the oil source and controller, unplug the oil pipe and data cable inside the X-ray 3D imaging instrument, remove the host from the turntable, place the host on the experimental platform outside the nanoVoxel-3000, connect the oil pipe and data transmission cable outside the X-ray 3D imaging instrument, and start the controller and oil source;

[0084] Step 9: In the in-situ test software interface of the computer, set the sample shape to plate, the loading type to cycle control, the loading frequency to 5 Hz, the control mode to displacement control, the control direction to tension, and the number of cycles to 10. 7 Wait, start the experiment;

[0085] Step 10: Experiment reaches cycle number 10 4 Finally, the experiment is ended, the force is unloaded to zero, the oil source and controller are turned off, and the oil pipe and data transmission line outside the X-ray three-dimensional imaging instrument are unplugged;

[0086] Step 11: Install the host after step 10 on the upper part of the turntable of the X-ray three-dimensional imaging instrument. The host is fixedly connected to the turntable through the base 1 with screws. The host is fixed with three locking screws at equal intervals in the circumferential direction, and the oil pipe and data transmission line inside the X-ray three-dimensional imaging instrument are connected;

[0087] Step 12: Perform 200N tensile load control on the sample, use nanoVoxel-3000 to perform 3D scanning, 3D reconstruction and 3D visualization on the sample, and obtain 3D information of the sample with a specific number of fatigue loading cycles;

[0088] Step 13: After the scan is completed, continue the fatigue test, repeat steps 8 to 9, and when the next set number of cycles is reached, end the test, unload the force to zero, turn off the oil source and controller, unplug the oil pipe and data transmission line outside the X-ray 3D imaging instrument, and repeat steps 11 to 12 until the 3D scan of multiple specific cycle stages is completed and the experimental results are obtained;

[0089] Step 14: After completing the experimental purpose, unload the force to zero, insert the guide rod 11, remove the screw 8 and the fastening screw 10, remove the upper supporting frame 23, remove the clamping screws (upper clamping screw 64 and lower clamping screw 54) and the sample pressing plate (sample upper pressing plate 63 and sample lower pressing plate 53), take out the sample, and turn off the software, computer, oil source and controller in turn.

[0090] The implementation results show that the overall design of the present invention overcomes the shortcomings of existing devices such as heavy weight, large size, narrow spectrum, small load, low efficiency, low resolution and poor adaptability, eliminates the adverse effects of in-situ high-frequency fatigue experiments and in-situ high-cycle fatigue experiments on X-ray three-dimensional imaging instruments, greatly improves the convenience, ease of use and three-dimensional image quality of in-situ fatigue three-dimensional imaging experiments, and can be widely used in a variety of X-ray three-dimensional imaging instruments and various types of metals, ceramics, plastics and composite materials. In-situ fatigue three-dimensional imaging research needs.

[0091] The above is a preferred embodiment of the present invention. It should be pointed out that all technicians in this technical field can make changes and / or modifications to the examples shown without departing from the principles of the present invention. These changes should also be regarded as the scope of protection of the present invention.

Claims

1. A wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device, characterized in that: The device mainly comprises: an oil source, a controller, a computer, an oil pipe, a data transmission line, and a host. The host is arranged inside or outside the X-ray three-dimensional imaging instrument. The device is provided with two sets of oil pipes: an internal oil pipe and an external oil pipe. One end of the internal oil pipe is connected to the oil source, and the other end of the internal oil pipe is extended to the inside of the X-ray three-dimensional imaging instrument for use. One end of the external oil pipe is connected to the oil source, and the other end of the external oil pipe is used outside the X-ray three-dimensional imaging instrument. The oil source transports hydraulic oil to the static pressure actuator cylinder of the static pressure actuator assembly on the host through the two sets of oil pipes respectively; the device is provided with two sets of data transmission lines: an internal data transmission line and an external data transmission line. One end of the internal data transmission line is connected to the output end of the controller, and the other end of the internal data transmission line is extended to the inside of the X-ray three-dimensional imaging instrument and connected to the servo valve on the host. One end of the external data transmission line is connected to the output end of the controller, and the other end of the external data transmission line is connected to the servo valve on the host outside the X-ray three-dimensional imaging instrument. The controller is connected to the computer through a line, and the controller controls the load and displacement of the host during fatigue test through the data transmission line.

2. The wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device according to claim 1 is characterized in that: The main machine includes a base, a load-bearing frame, a static pressure actuator assembly, a guide assembly, a lower clamp assembly, and an upper clamp assembly. The bottom of the load-bearing frame and the base can be detachably installed. The load-bearing frame is a split structure, including an upper load-bearing frame, a middle load-bearing frame, and a lower load-bearing frame. The upper load-bearing frame, the middle load-bearing frame, and the lower load-bearing frame are fixedly connected in sequence from top to bottom; the top of the upper load-bearing frame is connected to the upper clamp body of the upper clamp assembly by screws, and the middle and lower parts of the upper load-bearing frame are the load-bearing cylinders, which are connected to the middle parts by fastening screws. The load-bearing frame is connected to ensure that the upper fixture assembly remains stationary during the fatigue test; the specimen is installed between the upper fixture body of the upper fixture assembly and the lower fixture body of the lower fixture assembly on the inner side of the load-bearing cylinder, and the guide assembly is installed on the inner side of the middle load-bearing frame of the load-bearing frame to ensure that the lower fixture assembly moves linearly relative to the upper fixture assembly. The lower load-bearing frame also serves as the static pressure actuator cylinder of the static pressure actuator assembly. The static pressure actuator assembly is used to drive the lower fixture assembly to perform fatigue dynamic movement. The fatigue frequency range is: 0.01Hz to 300Hz.

3. The wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device according to claim 2 is characterized in that: The hydrostatic actuator assembly includes a piston rod, a hydrostatic actuator cylinder, a lower cylinder head, an upper cylinder head and a piston. The inner cavity of the hydrostatic actuator cylinder is equipped with a piston rod, a lower cylinder head, an upper cylinder head and a piston. The upper and lower parts of the piston rod are respectively penetrated through the upper cylinder head and the lower cylinder head of the cylinder and are slidably matched. The middle part of the piston rod is provided with a piston that is slidably matched with the inner cavity of the hydrostatic actuator cylinder. The servo valve on the outside of the lower supporting frame is connected to the inner cavity of the hydrostatic actuator cylinder located above and below the piston through the oil inlet channel and the oil return channel inside the lower supporting frame, respectively, so that the hydraulic oil is reciprocatedly supplied and returned at the upper and lower ends of the piston to push the piston rod up and down.

4. The wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device according to claim 2 is characterized in that: The guide assembly includes a sensor connecting plate, a guide rail connecting plate, a slider, a guide rail, a load sensor, and a transition plate. The sensor connecting plate is connected to the upper end of the piston rod. The bottom and both sides of the guide rail connecting plate are respectively connected to the sensor connecting plate and the slider. The two guide rails are symmetrically installed on the inner wall of the middle load-bearing frame. The two sides of the guide rail connecting plate correspond to the guide rails through the sliders and are in sliding cooperation to ensure that the piston rod moves in a straight line during the up and down movement without rotation; the lower end of the load sensor is connected to the sensor connecting plate, and the upper end of the load sensor is connected to the transition plate.

5. The wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device according to claim 2 is characterized in that: The lower clamp assembly includes a lower clamp body, a lower gasket, a specimen lower pressure plate, and a lower clamping screw. The lower clamp assembly is installed on the transition plate of the guide assembly through the lower clamp body. The lower part of the specimen is inserted into the lower clamp body. The lower gasket used for specimen adjustment is installed in the lower clamp body and is located on one side of the lower part of the specimen. A specimen lower pressure plate is arranged on the other side of the lower part of the specimen. The lower clamping screw passes through the specimen lower pressure plate to clamp and fix the lower part of the specimen. The upper clamp assembly includes an upper clamp body, an upper gasket, a specimen upper pressure plate, and an upper clamping screw. The upper clamp assembly is fixed to the upper bearing frame by screws. The upper part of the specimen is inserted into the upper clamp body. The upper gasket is installed in the upper clamp body and is located on one side of the upper part of the specimen. An specimen upper pressure plate is arranged on the other side of the upper part of the specimen. The upper clamping screw passes through the specimen upper pressure plate to clamp and fix the upper part of the specimen.

6. The wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device according to claim 2 is characterized in that: The top through hole opened on the top of the upper supporting frame, the upper through hole opened on the upper clamp body, and the lower through hole opened on the lower clamp body are coaxially corresponding to each other, and the guide rod passes through the top through hole, the upper through hole, and the lower through hole in sequence; when in use, the upper supporting frame is removed independently as needed: first, the guide rod is inserted into the upper through hole, the lower through hole and the top through hole to connect the lower clamp body and the upper clamp body; then, the fastening screws and screws are removed to remove the upper supporting frame.

7. The wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device according to claim 2 is characterized in that: The specifications of the host are as follows: outer diameter ≤100mm, height ≤240mm, weight ≤8kg; when the host is set outside the X-ray three-dimensional imaging instrument, the host is directly placed on the experimental platform through the base; when the host is set inside the X-ray three-dimensional imaging instrument, the host is fixedly installed on the turntable of the X-ray three-dimensional imaging instrument through the base.

8. The wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging device according to claim 2 is characterized in that: The material of the bearing tube is carbon fiber material, engineering plastic, organic glass or metal material.

9. The method for testing wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging according to any one of claims 1 to 8, characterized in that: The steps include: Step 1: Select the X-ray 3D imaging instrument according to your needs; Step 2: Install the host on the turntable of the X-ray three-dimensional imaging instrument. The host is fixedly connected to the turntable through the base 1 with screws. The host is fixed with three locking screws at equal intervals in the circumferential direction, and the oil pipe and data transmission line inside the X-ray three-dimensional imaging instrument are connected; Step 3: Start the controller, power on the oil source, press the reset button, and start the oil source; Step 4: Before installing the specimen, move the piston rod of the static pressure actuator assembly upward until it approaches the upper limit position; Step 5: First insert the guide rods into the upper through hole, the lower through hole and the top through hole, remove the upper bearing frame, put the upper gasket into the upper fixture body, put the lower gasket into the lower fixture body, put the fatigue specimen in, put both ends of the specimen completely into the upper fixture body and the lower fixture body, press them with the upper and lower specimen pressing plates respectively, and fix them with the upper and lower pressing screws; Step 6: Install the upper bearing frame, secure it with screws and fastening screws, and pull out the guide rods; Step 7: Use an X-ray three-dimensional imaging instrument to perform three-dimensional scanning, three-dimensional reconstruction, and three-dimensional visualization on the sample to obtain three-dimensional information of the sample before loading; Step 8: In the in-situ test software interface of the computer, set the specimen shape, loading type, control direction, control method, number of cycles, and start the fatigue test; Step 9: After the fatigue test reaches the target number of cycles, the fatigue test is paused or ended; Step 10: Perform tensile load-keeping control on the sample, and use an X-ray three-dimensional imaging instrument to perform three-dimensional scanning, three-dimensional reconstruction, and three-dimensional visualization on the sample to obtain three-dimensional information of the sample at a specific number of fatigue loading cycles; Step 11: After the scan is completed, continue the fatigue test and repeat steps 9 to 10 until the experimental purpose is achieved; Step 12: After completing the experimental purpose, unload the force to zero, insert the guide rod, remove the screws and fastening screws, remove the upper load-bearing frame, remove the clamping screws and the specimen clamp, remove the specimen, and turn off the in-situ test software, computer, oil source and controller in turn.

10. The method for testing wide spectrum, large load, high efficiency and high resolution in-situ fatigue three-dimensional imaging according to claim 9, characterized in that: Select the second test process according to your needs, including the following steps: Step 13: Repeat steps 1 to 7; Step 14: Turn off the oil source and controller, unplug the oil pipe and data cable inside the X-ray 3D imaging instrument, remove the host from the turntable, place the host on the experimental platform outside the X-ray 3D imaging instrument, and connect the oil pipe and data transmission cable outside the X-ray 3D imaging instrument; Step 15: Start the controller and the oil source, repeat steps 8 to 9, unload the force to zero, turn off the oil source and the controller, and unplug the oil pipe and data transmission line outside the X-ray three-dimensional imaging instrument; Step 16: Install the host after step 15 on the upper part of the turntable of the X-ray three-dimensional imaging instrument. The host is fixedly connected to the turntable through the base with screws. The host is fixed with three locking screws at equal intervals in the circumferential direction, and the oil pipe and data transmission line inside the X-ray three-dimensional imaging instrument are connected; Step 17: Repeat step 10; Step 18: Repeat steps 14 to 17 until the experimental purpose is completed, then repeat step 12.

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