In-situ mechanical testing device and testing method of nanoindentation system

Abstract

The present application relates to the technical field of rock mechanics test, and more particularly to a nanoindentation system in-situ mechanical test device and test method, the test device is installed on the test instrument base, comprising a test instrument base, a loading platform is installed on the test instrument base, the loading platform comprises an adjusting box, clamping assemblies are symmetrically arranged at the two ends of the adjusting box, a telescopic cylinder is connected between the adjusting box and the clamping assemblies, and side support assemblies are movably arranged on the two sides of the adjusting box; the clamping assembly comprises a clamping block, a locking sliding block is movably arranged at one end of the clamping block, and an adjusting sliding block is arranged at the other end of the clamping block, the adjusting sliding block is slidably connected or separated from the clamping block, a rotating pressing plate is rotatably arranged on the locking sliding block, the side support assembly further comprises an adjusting cylinder, and the telescopic end of the adjusting cylinder is slidably matched with the adjusting sliding block through an adjusting block; the test method is applied to the test device, a cuboid rock sample is clamped, a bidirectional compression force or a shear force or a tensile force is applied to the sample through the telescopic cylinder and the adjusting cylinder, and internal stress of the rock material is simulated.

Description

Technical Field

[0001] This invention relates to the field of rock mechanics testing technology, and in particular to an in-situ mechanical testing device and method for a nanoindentation system. Background Technology

[0002] Nanoindentation is a technique that uses a small load to press into the surface of a material and records the displacement of the indenter in real time to calculate the material's hardness, elastic modulus, nano-scratches, coefficient of friction, yield strength, and interfacial bonding force. Studying the microstructure, mineral composition, and micromechanical characteristics of rocks using nanoindentation is of great significance. In nanoindentation tests, rock samples are typically placed directly into the nanoindentation testing device for parameter measurement. The rock is not subjected to lateral loads. Most in-situ mechanical tests of rocks test their properties under in-situ conditions and stress. In the actual rock environment, the rock material contains tensile stress, compressive stress, or shear stress. Existing nanoindentation testing devices have limitations in in-situ mechanical testing of rocks. Summary of the Invention

[0003] The purpose of this invention is to provide an in-situ mechanical testing device and method for a nanoindentation system to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] An in-situ mechanical testing device for a nanoindentation system includes a testing instrument base, a loading stage, clamping components, and a side support assembly. The loading stage is mounted on the testing instrument base. The loading stage includes an adjustment box, with clamping components centrally symmetrically arranged at both ends. A telescopic cylinder connects the adjustment box and the clamping components. Both sides of the adjustment box are connected to gears on the side support assembly via racks. The clamping component includes a clamping block, with a locking slider slidably mounted at one end via a locking cylinder, and an adjusting slider at the other end. The adjusting slider is slidably connected to or separated from the clamping block. A rotating pressure plate is rotatably mounted on the locking slider. The side support assembly also includes an adjustment cylinder, with its telescopic end slidingly engaging with the adjusting slider via an adjustment block. A placement stage is connected to the center of the adjustment box via a lifting cylinder, and a sample is placed on the upper surface of the placement stage. The clamping blocks in the two clamping assemblies respectively abut against both ends of the sample.

[0006] Preferably, when the specimen is under tensile stress, the adjusting slider is slidably connected to the clamping plate, the rotating pressure plate is in a horizontal position, the two adjusting sliders are staggered, and the rotating pressure plate and the corresponding adjusting slider abut against the two side walls of the specimen and cooperate to clamp the specimen; when the specimen is under bidirectional compressive stress, the adjusting slider is separated from the clamping plate, the rotating pressure plate is in a vertical position, the two adjusting sliders are aligned, and the adjusting sliders abut against the two side walls of the specimen; when the specimen is under shear stress, the adjusting slider is separated from the clamping plate, the rotating pressure plate is in a vertical position, the two adjusting sliders are staggered, and the adjusting sliders in the two clamping assemblies abut against the two side walls of the specimen.

[0007] Preferably, the locking slider and the clamping block are fixedly connected by a sliding rod at the end. A locking cylinder is installed on the side of the clamping block away from the sample. The telescopic end of the locking cylinder is fixedly connected to the locking slider. The rotating pressure plate is adjusted by a worm gear mechanism to achieve parallel or perpendicular arrangement with the locking slider.

[0008] Preferably, a blind groove is provided in the middle of the bottom surface of the adjusting slider, and a moving groove is provided on the side of the adjusting slider away from the sample. The adjusting slider is slidably inserted into or separated from the mating block fixedly set at the bottom of the clamping block through the blind groove; the adjusting slider is slidably mated with the adjusting block through the moving groove.

[0009] Preferably, the side support assembly further includes a connecting block, racks are fixedly arranged on both sides of the adjustment box, a guide rail is fixedly arranged above the racks, a guide groove is provided on the side of the connecting block, the guide groove slides with the guide rail, and a gear is rotatably arranged on the connecting block, the gear meshing with the rack.

[0010] Preferably, an adjusting cylinder is installed on the connecting block, and a moving block is connected to the telescopic end of the adjusting cylinder. The moving block and the adjusting block are slidably connected, and the two sides of the moving block abut against the sides of the adjusting block through springs.

[0011] Preferably, the clamping assembly includes a fixed plate, the middle part of the clamping block is fixedly connected to the fixed plate via a mounting rod, the fixed plate is fixedly connected to the telescopic end of the telescopic cylinder, the fixed end of the telescopic cylinder is fixedly disposed at the end of the adjustment box, and two sliding rods are fixedly disposed in parallel inside the adjustment box, and the two sliding rods are slidably connected to the lower part of the fixed plate.

[0012] Preferably, the testing instrument base is equipped with a loading system and a moving system, the moving system is connected to a loading platform, the loading system is equipped with a pressure head, the sample is a cuboid rock sample, and a protective cover is provided outside the testing instrument base.

[0013] An in-situ mechanical testing method for a nanoindentation system, applied to the aforementioned in-situ mechanical testing apparatus for a nanoindentation system, includes the following steps:

[0014] S1: According to the size of the sample, adjust the extension end of the lifting cylinder to drive the placement platform to rise. After placing the sample on the surface of the placement platform, adjust the lifting cylinder in the opposite direction to lower the placement platform to the appropriate position.

[0015] S2: Adjust the connection or separation of the clamping block and the adjusting slider according to the test requirements. If the simulated sample is under bidirectional compression or shear stress, move the adjusting slider to separate from the clamping block; if the simulated sample is under tensile stress, adjust the adjusting slider to slide and the clamping block; adjust the telescopic cylinder to make the clamping block abut against the sample.

[0016] S3: Based on the in-situ mechanical test of the mechanical performance parameters of the simulated specimen under stress, the rotating pressure plate and the adjusting slider are adjusted to the corresponding positions respectively. When the simulated specimen is subjected to bidirectional compressive force, the adjusting cylinders in the two side support components are set opposite to each other. When the simulated specimen is subjected to shear force, the extrusion force applied to the specimen by the two adjusting cylinders is staggered. When the simulated specimen is subjected to tensile force, the adjusting cylinder is located at the end where the adjusting slider abuts against the specimen.

[0017] S4: Sealed protective cover, adjust the loading stage to make the sample correspond to the loading system, input the set parameters into the test instrument base, and plan the indentation dot matrix on the sample surface.

[0018] S5: The corresponding telescopic cylinder and adjusting cylinder are activated to apply compressive force, shear force or tensile force to the sample; the loading system is adjusted to dynamically load the sample according to the planned indentation lattice;

[0019] S6: After the test is completed, open the protective cover, unload the sample, and adjust the mechanical testing device to reset.

[0020] Compared with the prior art, the present invention has the following beneficial effects:

[0021] This invention provides an in-situ mechanical testing device for a nanoindentation system. An adjustment box is mounted on the base of the testing instrument. Both ends of the adjustment box are connected to clamping components via telescopic cylinders. Side support components are movably connected to both sides of the adjustment box. The clamping components include clamping blocks, with a locking slider movably mounted at one end and an adjusting slider at the other end. The adjusting slider is slidably connected to or separated from the clamping block. A rotating pressure plate is rotatably mounted on the locking slider. The side support components also include an adjusting cylinder. The telescopic end of the adjusting cylinder is slidably connected to the adjusting slider via an adjusting block. During the test, the telescopic cylinder and the adjusting cylinder can be adjusted to apply opposing compressive forces to the sample in two directions, causing compressive stress; or to apply staggered compressive forces to the sample, causing shear stress; or to apply tensile forces to the sample in one direction, causing tensile stress. This allows for comprehensive simulation of the in-situ state and stress conditions of rock materials, avoiding the need to replace the adjustment device during the test, reducing operational steps, and eliminating the need for recalibration.

[0022] This invention provides an in-situ mechanical testing method for a nanoindentation system, which is applied to an in-situ mechanical testing device for a nanoindentation system. According to the test requirements, cuboid rock samples of different sizes are selected for clamping. By adjusting the telescopic cylinder and the adjusting cylinder, bidirectional compressive force, shear force or tensile force is applied to the sample to simulate the real stress state inside the rock material, which further increases the accuracy of nanoindentation testing. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the connection structure of an in-situ mechanical testing device for a nanoindentation system according to an embodiment of the present invention;

[0024] Figure 2 This is a partial exploded structural diagram of the in-situ mechanical testing device for a nanoindentation system according to an embodiment of the present invention;

[0025] Figure 3 This is a schematic diagram of the clamping component connection structure in an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram of the side support component connection structure in an embodiment of the present invention;

[0027] Figure 5 for Figure 2 Enlarged view of region A in the middle;

[0028] Figure 6 This is a schematic diagram of the connection structure of the clamping component in an embodiment of the present invention;

[0029] Figure 7 This is a top-view schematic diagram of the connection structure when a sample is subjected to bidirectional compressive force according to an embodiment of the present invention.

[0030] Figure 8 This is a top-view schematic diagram of the connection structure when simulating a sample under shear force according to an embodiment of the present invention;

[0031] Figure 9 This is a top-view schematic diagram of the connection structure when simulating a sample under tensile force according to an embodiment of the present invention.

[0032] Figure label:

[0033] 1. Test instrument base; 11. Loading system; 12. Imaging system; 13. Moving system; 2. Loading platform; 21. Adjustment box; 211. Adjustment cavity; 22. Slide rod; 23. Rack; 24. Guide rail; 3. Clamping assembly; 31. Clamping block; 311. Matching rod; 312. Matching block; 313. Support plate; 32. Locking slider; 321. Boss; 322. Connecting platform; 33. Adjusting slider; 331. Blind groove; 332. Moving groove; 34. Rotating pressure plate; 35. Fixed plate; 36. Worm gear; 37. Worm wheel; 38. Locking cylinder; 4. Side support assembly; 41. Connecting block; 411. Guide groove; 42. Adjusting cylinder; 43. Moving block; 44. Gear; 45. Driving component; 46. Adjusting block; 461. Guide block; 47. Guide rod; 5. Sample; 6. Telescopic cylinder; 7. Placement platform; 8. Lifting cylinder. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] In the following description of the invention, it should be noted that the terms "upper," "lower," "left," "right," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation. The term "connection" simply indicates a connection between devices and has no special meaning.

[0036] Furthermore, the technical fields and installation methods involved in the embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0037] For specific implementation examples, please refer to: Figures 1-6An in-situ mechanical testing device for a nanoindentation system includes a testing instrument base 1, a loading stage 2, clamping components 3, side support components 4, a sample 5, a telescopic cylinder 6, a placement platform 7, and a lifting cylinder 8. The loading stage 2 is mounted on the testing instrument base 1. The loading stage 2 includes an adjustment box 21, with clamping components 3 centrally symmetrically arranged at both ends of the adjustment box 21. A telescopic cylinder 6 connects the adjustment box 21 and the clamping components 3. The two sides of the adjustment box 21 are respectively connected to gears 44 on the two side support components 4 via racks 23. The middle of the adjustment box 21 is connected to the placement platform 7 via the lifting cylinder 8. The sample 5 is placed on the upper surface of the placement stage 7; the clamping assembly 3 includes a clamping block 31, one end of which is movably provided with a locking slider 32 via a locking cylinder 38, and the other end of which is provided with an adjusting slider 33. The adjusting slider 33 is slidably connected to or separated from the clamping block 31. The side of the adjusting slider 33 away from the locking slider 32 is slidably connected to the adjusting block 46 in the side support assembly 4. The side support assembly 4 also includes a connecting block 41, on which an adjusting cylinder 42 is installed. A moving block 43 is fixedly provided at the telescopic end of the adjusting cylinder 42, and the moving block 43 is slidably engaged with the adjusting block 46.

[0038] The testing instrument base 1 is equipped with a loading system 11, an imaging system 12, a moving system 13, and a control system. The loading system 11 can apply a load, and a pressure head is provided at the bottom of the loading system 11. The height of the loading system 11 can be adjusted by moving the pressure head vertically. The testing instrument base 1 is equipped with a moving system 13, on which a loading platform 2 is mounted. The moving system 13 drives the loading platform 2 to move longitudinally or laterally on the horizontal plane. The moving system 13 can adopt a piezoelectric ceramic drive system or an air-bearing guide rail system to drive the loading platform 2 to move in the x and y directions. The specific moving system 13 is existing technology and will not be described in detail. The pressure head can be directly pressed into the surface of the sample 5. The sample 5 is a rectangular rock sample. Each test uses sample 5. The sizes of the specimens vary, and the size of the placement stage 7 can be different from that of the specimen 5. The mechanical properties of the specimen 5 are reflected by the indentation on its surface after the test. The imaging system 12 includes a camera and an optical microscope. Initial parameters such as maximum load, indentation depth, and loading rate are input to the control system. The loading system 11, the indenter action, and data acquisition are automatically controlled. The camera monitors the entire test process and can also capture images of the indentation point location and shape. The optical microscope can assist the indenter in accurately locating the indentation area. The optical microscope can also perform dynamic indentation morphology tracking, record the indentation formation process in real time, and measure the actual size of the indentation. The protective cover set on the outside of the test instrument base 1 is sealed during the test and opened after the test.

[0039] The clamping assembly 3 also includes a fixing plate 35. The side of the clamping block 31 away from the sample 5 is fixedly connected to the fixing plate 35 via a fixed mounting rod. A support plate 313 is vertically fixed on the side of the clamping block 31 facing the fixing plate 35, and the support plate 313 is located at the end of the clamping block 31. A mating rod 311 is fixedly installed on the end wall of the clamping block 31 with the support plate 313, and a mating block 312 is fixedly installed at the bottom of the other end of the clamping block 31. The mating block 312 is approximately L-shaped. A locking slider 32 is slidably installed on the mating rod 311. A boss 321 is provided on the side of the locking slider 32 facing the fixing plate 35, and a rotating pressure plate 34 is rotatably installed on the other side. The support plate 313 and the locking slider 32 are located at the same end of the clamping block 31. A locking cylinder 38 is installed on the support plate 313. The telescopic end of the locking cylinder 38 passes through the support plate 313 and is fixedly connected to the boss 321. The extension or retraction of the telescopic end of the locking cylinder 38 can adjust the locking slider 32 to move closer to or further away from the sample 5 along the axial direction of the mating rod 311. A connecting shaft is rotatably provided at the end of the locking slider 32 that is rotatably connected to the rotating pressure plate 34. A worm gear 37 and the rotating pressure plate 34 are fixedly sleeved on the connecting shaft. A connecting platform 322 is fixedly provided on the side of the locking slider 32 away from the boss 321. A worm 36 is rotatably provided on the connecting platform 322. The worm 36 is connected to the worm gear 37 through a transmission. The worm 36 is driven by a knob to drive the worm gear 37 to rotate, so that the rotating pressure plate 34 rotates to be parallel or perpendicular to the locking slider 32. The worm gear structure has a self-locking function to prevent the rotating pressure plate 34 from shifting after rotating to the set position.

[0040] When the simulated sample 5 is subjected to tensile force, the rotating pressure plate 34 is rotated to make it parallel to the locking slider 32, and the locking cylinder 38 is adjusted to drive the locking slider 32 and the rotating pressure plate 34 to approach the sample 5 until the side wall of the rotating pressure plate 34 contacts the side wall of the sample 5.

[0041] When the simulated sample 5 is subjected to bidirectional compressive or shear force, the rotating pressure plate 34 is adjusted to be perpendicular to the locking slider 32, and the locking slider 32 is adjusted to be located at the end of the mating rod 311. At this time, the locking slider 32 and the rotating pressure plate 34 do not affect the proximity of the adjusting slider 33 in their relative clamping assembly 3.

[0042] The adjustment slider 33 has a blind groove 331 in the middle of its bottom surface and a moving groove 332 on the side of the adjustment slider 33 away from the sample 5. The adjustment slider 33 is slidably inserted into or separated from the mating block 312 on the clamping block 31 through the blind groove 331. The moving groove 332 is slidably inserted into the adjustment block 46 in the side support assembly 4.

[0043] When the simulated sample 5 is subjected to bidirectional compressive force, the length of the sample 5 is greater than the length of the adjusting slider 33, and the width of the sample 5 is greater than the length of the clamping block 31. At this time, there is a gap between the side wall of the adjusting slider 33 facing the sample 5 and the mating block 312, so as to avoid direct collision between the adjusting slider 33 and the mating block 312 when the adjusting cylinder 42 applies the compressive force, which would cause damage. When the sample 5 is subjected to bidirectional pressure, it deforms, and the adjusting slider 33 and the two clamping blocks 31 have a displacement distance.

[0044] When the simulated sample 5 is subjected to shear force, the width of the sample 5 is greater than the length of the clamping block 31. The adjusting slider 33 is moved to separate it from the clamping block 31. The telescopic cylinder 6 and the adjusting cylinder 42 are adjusted to make the clamping block 31, the adjusting slider 33 and the sample 5 come into contact. When the sample 5 may deform under shear force, the adjusting slider 33 has a displacement distance.

[0045] The loading platform 2 also includes a slide rod 22. The adjustment box 21 has an adjustment cavity 211. The adjustment cavity 211 extends outward from both sides and passes through the mounting cavity. The mounting cavity and the adjustment cavity 211 are connected. The two slide rods 22 are fixedly installed on both sides inside the adjustment box 21. The two slide rods 22 are parallel and located below the placement platform 7. The slide rods 22 are slidably connected to the lower part of the clamping assembly 3. The two side walls of the adjustment box 21 are fixedly installed with racks 23. The racks 23 are fixedly installed on the upper part of the racks 23. The guide rails 24 are fixedly installed on the upper part of the racks 23.

[0046] The length of the adjusting slider 33 is greater than that of the locking slider 32. The lower part of the fixing plate 35 extends downward. Sliding holes are opened on both sides of the fixing plate 35. The two sliding holes are slidably engaged with the two sliding rods 22 respectively. The other side of the fixing plate 35 is fixedly connected to the telescopic end of the telescopic cylinder 6. The fixed end of the telescopic cylinder 6 is fixedly installed in the mounting cavity at the end of the adjusting box 21.

[0047] A guide groove 411 is fixedly provided on the side of the connecting block 41 away from the sample 5, and a vertical plate is fixedly provided on the other side. An adjusting cylinder 42 is installed on the vertical plate. The telescopic end of the adjusting cylinder 42 passes through the vertical plate and is fixedly connected to the moving block 43. The moving block 43 is slidably connected to the adjusting block 46. The two sides of the moving block 43 abut against the sides of the adjusting block 46 through springs. A guide rod 47 is fixedly provided in the middle of the moving block 43. The two ends of the guide rod 47 extend outward and pass through the adjusting block 46, and slide with the two sides of the adjusting block 46. A guide block 461 is fixedly provided on the side of the adjusting block 46 facing the adjusting slider 33. The guide block 461 slides with the moving groove 332 on the adjusting slider 33. When the connecting block 41 drives the adjusting block 46 to move at a certain speed and contact the end of the moving groove 332, the spring deforms and absorbs the impact force of the adjusting block 46 to avoid equipment damage.

[0048] A driving component 45 is fixedly provided at the end of the connecting block 41. The driving component 45 is connected to the gear 44 and drives the gear 44 to rotate. The rack 23 is meshed with the gear 44. The rotation of the gear 44 drives the connecting block 41 to move along the guide rail 24, thereby adjusting the relative position of the side support assembly 4 and the sample 5.

[0049] When the adjusting block 46 moves the adjusting slider 33, the rotating gear 44 drives the connecting block 41, adjusting cylinder 42, moving block 43 and adjusting block 46 to move along the moving groove 332 on the adjusting slider 33 to a position near the end, thereby moving the adjusting slider 33 and adjusting the relative displacement between the adjusting slider 33 and the clamping block 31.

[0050] When the clamping assembly 3 and the side support assembly 4 clamp the sample 5, the lifting cylinder 8 is adjusted to extend its telescopic end, causing the placement platform 7 to rise. After the sample 5 is placed on the surface of the placement platform 7, the lifting cylinder 8 is adjusted in the opposite direction to descend to a suitable position according to the size of the sample 5. According to the test requirements, the clamping block 31 and the adjusting slider 33 are first adjusted to connect or separate. If the sample 5 is subjected to bidirectional compressive force or shear force, the slider 33 is first adjusted to separate from the clamping block 31. If the sample 5 is subjected to tensile force, the clamping block 31 and the adjusting slider 33 are adjusted to slide together. Then the telescopic cylinder 6 and the adjusting cylinder 42 are adjusted to make the clamping block 31, the adjusting slider 33 and the sample 5 come into contact.

[0051] When the simulated specimen 5 is subjected to bidirectional compressive force, such as Figure 7 As shown, the rotating pressure plate 34 is located on the end of the mating rod 311 away from the sample 5, and the rotating pressure plate 34 is perpendicular to the locking slider 32. The adjusting slider 33 is separated from the clamping block 31. The two adjusting sliders 33 are moved to align, and the two adjusting sliders 33 and the two clamping blocks 31 are arranged in a rectangle. At this time, the axes of the two adjusting cylinders 42 are collinear. The telescopic cylinder 6 applies a squeezing force to the sample 5. At the same time, the adjusting cylinders 42 in the two side support assemblies 4 apply pressure to the sample 5.

[0052] When the simulated specimen 5 is subjected to shear force, such as Figure 8 As shown, the rotating pressure plate 34 is located on the end of the mating rod 311 away from the sample 5, and the rotating pressure plate 34 is set perpendicular to the locking slider 32. The adjusting slider 33 is separated from the clamping block 31. The two adjusting sliders 33 are moved to both sides of the sample 5 respectively, and the two adjusting sliders 33 are staggered. The two adjusting blocks 46 are adjusted to be located at both ends of the sample 5 and at equal distances from the center line of the sample 5, so that the pressure directions applied by the two adjusting cylinders 42 to the sample 5 are staggered. The extension of the telescopic cylinder 6 is adjusted to remain unchanged after reaching the set length. At least one adjusting cylinder 42 is adjusted to apply the extrusion force.

[0053] When the simulated specimen 5 is subjected to tensile force, such as Figure 9As shown, adjust the rotating pressure plate 34 to rotate until it is parallel to the locking slider 32, and adjust the locking slider 32 to approach the sample 5 until the rotating pressure plate 34 abuts against the sample 5; adjust the slider 33 to slide and connect with the clamping block 31, adjust the two adjusting sliders 33 so that their opposite ends are opposite to the rotating pressure plate 34, move the adjusting block 46 to the end of the adjusting slider 33 that abuts against the sample 5, and apply a set pressure to the sample 5 with the adjusting cylinder 42 and the locking cylinder 38 so that the locking slider 32 and the adjusting slider 33 cooperate to clamp the sample 5; the telescopic cylinder 6 applies a pulling force to the sample 5.

[0054] An in-situ mechanical testing method for a nanoindentation system, applied to an in-situ mechanical testing device for a nanoindentation system, includes the following steps:

[0055] S1: According to the size of the sample 5, adjust the extension end of the lifting cylinder 8 to drive the placement platform 7 to rise. After placing the sample 5 on the surface of the placement platform 7, adjust the lifting cylinder 8 in the opposite direction to lower the placement platform 7 to the appropriate position.

[0056] S2: According to the test requirements, adjust the connection or separation of the clamping block 31 and the adjusting slider 33. If the simulated sample 5 is subjected to bidirectional compressive force or shear force, move the adjusting slider 33 to separate from the clamping block 31; if the simulated sample 5 is subjected to tensile force, adjust the adjusting slider 33 to slide and connect with the clamping block 31; adjust the telescopic cylinder 6 to make the clamping block 31 abut against the sample 5.

[0057] S3: Based on the in-situ mechanical test of the mechanical performance parameters of the simulated specimen 5 under stress, the rotating pressure plate 34 and the adjusting slider 33 are adjusted to the corresponding positions respectively; when the simulated specimen 5 is subjected to bidirectional compressive force, the adjusting cylinders 42 in the two side support components 4 are set opposite to each other; when the simulated specimen 5 is subjected to shear force, the compressive force applied to the specimen 5 by the two adjusting cylinders 42 is staggered; when the simulated specimen 5 is subjected to tensile force, the adjusting cylinder 42 is located at the end where the adjusting slider 33 abuts against the specimen 5.

[0058] S31: When the simulated sample 5 is subjected to bidirectional compressive force, the rotating pressure plate 34 is in a vertical position on the end of the mating rod 311 away from the sample 5, and the two adjusting sliders 33 move to align and abut against the two sides of the sample 5 respectively.

[0059] S32: When the simulated sample 5 is subjected to shear force, the rotating pressure plate 34 is in a vertical position on the end of the mating rod 311 away from the sample 5. The two adjusting sliders 33 are staggered on both sides of the sample 5. The extension of the telescopic cylinder 6 is adjusted to a set length and then remains unchanged.

[0060] S33: When the simulated sample 5 is subjected to tensile force, the two adjusting sliders 33 are staggered on both sides of the sample 5, the rotating pressure plate 34 is in a horizontal state and the rotating pressure plate 34 abuts against the sample 5, and the adjusting slider 33 and the locking slider 32 cooperate to clamp the sample 5.

[0061] S4: Sealed protective cover, adjust loading stage 2 to make the sample correspond to loading system 11, input the set parameters into the test instrument base 1, and plan the indentation dot matrix on the surface of sample 5.

[0062] S5: The corresponding telescopic cylinder 6 and adjusting cylinder 42 are activated to apply compressive force, shear force or tensile force to the sample 5; the loading system 11 is adjusted to dynamically load the sample 5 according to the planned indentation grid.

[0063] S6: After the test is completed, open the protective cover, unload the sample 5, and adjust the mechanical testing device to reset.

Claims

1. An in-situ mechanical testing device for a nanoindentation system, characterized in that: The instrument includes a testing base, a loading stage, clamping components, and side support components. The loading stage is mounted on the testing base. The loading stage includes an adjustment box, with clamping components symmetrically arranged at both ends. A telescopic cylinder connects the adjustment box and the clamping components. Both sides of the adjustment box are connected to gears on the side support components via racks. Each clamping component includes a clamping block. One end of the clamping block has a locking slider slidably mounted via a locking cylinder, and the other end has an adjusting slider. The adjusting slider is slidably connected to or separated from the clamping block. A rotating pressure plate is rotatably mounted on the locking slider. The side support components also include an adjustment cylinder, with its telescopic end slidingly engaging with the adjusting slider via an adjustment block. A lifting cylinder connects the middle of the adjustment box to a placement stage, on which a sample is placed. The clamping blocks in the two clamping components abut against both ends of the sample. When the specimen is under tensile stress, the adjusting slider is slidably connected to the clamping plate, the rotating pressure plate is in a horizontal position, the two adjusting sliders are staggered, and the rotating pressure plate and the corresponding adjusting sliders abut against the two side walls of the specimen, thus clamping the specimen. When the specimen is under bidirectional compressive stress, the adjusting slider is separated from the clamping plate, the rotating pressure plate is in a vertical position, the two adjusting sliders are aligned, and the adjusting sliders abut against the two side walls of the specimen. When the specimen is under shear stress, the adjusting slider is separated from the clamping plate, the rotating pressure plate is in a vertical position, the two adjusting sliders are staggered, and the adjusting sliders in the two clamping assemblies abut against the two side walls of the specimen. The testing instrument base is equipped with a loading system and a moving system. The moving system is connected to a loading platform. The loading system is equipped with a pressure head. The sample is a rectangular rock sample. A protective cover is installed outside the testing instrument base.

2. The in-situ mechanical testing device for a nanoindentation system according to claim 1, characterized in that: The locking slider is slidably connected to the mating rod fixedly installed at the end of the clamping block. A locking cylinder is installed on the side of the clamping block away from the sample. The telescopic end of the locking cylinder is fixedly connected to the locking slider. The rotating pressure plate is adjusted by a worm gear mechanism to achieve parallel or perpendicular setting with the locking slider.

3. The in-situ mechanical testing device for a nanoindentation system according to claim 1, characterized in that: A blind groove is provided in the middle of the bottom surface of the adjusting slider, and a moving groove is provided on the side of the adjusting slider away from the sample. The adjusting slider slides into or separates from the mating block fixedly set at the bottom of the clamping block through the blind groove; the adjusting slider slides into the adjusting block through the moving groove.

4. The in-situ mechanical testing device for a nanoindentation system according to claim 1, characterized in that: The side support assembly also includes a connecting block, racks are fixedly installed on both sides of the adjustment box, a guide rail is fixedly installed above the racks, a guide groove is provided on the side of the connecting block, the guide groove slides with the guide rail, and a gear is rotatably installed on the connecting block, the gear meshes with the rack.

5. The in-situ mechanical testing device for a nanoindentation system according to claim 4, characterized in that: An adjusting cylinder is installed on the connecting block. A moving block is connected to the telescopic end of the adjusting cylinder. The moving block and the adjusting block are slidably connected. The two sides of the moving block abut against the sides of the adjusting block through springs.

6. The in-situ mechanical testing device for a nanoindentation system according to claim 5, characterized in that: The clamping assembly includes a fixed plate, and the middle part of the clamping block is fixedly connected to the fixed plate via a mounting rod. The fixed plate is fixedly connected to the telescopic end of the telescopic cylinder. The fixed end of the telescopic cylinder is fixedly installed at the end of the adjustment box. Two sliding rods are fixedly installed in parallel inside the adjustment box, and the two sliding rods are slidably connected to the lower part of the fixed plate.

7. An in-situ mechanical testing method for a nanoindentation system, applied to the in-situ mechanical testing apparatus for a nanoindentation system as described in any one of claims 1-6, characterized in that: Includes the following steps: S1: Prepare the test specimens required for the test. According to the size of the specimens, adjust the extension end of the lifting cylinder to drive the placement platform to rise. After placing the specimens on the surface of the placement platform, adjust the lifting cylinder in the opposite direction to lower the placement platform to the appropriate position. S2: Adjust the connection or separation of the clamping block and the adjusting slider according to the test requirements. If the simulated sample is under bidirectional compression or shear stress, move the adjusting slider to separate from the clamping block; if the simulated sample is under tensile stress, adjust the adjusting slider to slide and the clamping block; adjust the telescopic cylinder to make the clamping block abut against the sample. S3: Based on the in-situ mechanical test of the mechanical performance parameters of the simulated specimen under stress, adjust the rotating pressure plate and the adjusting slider to the corresponding positions respectively; when the simulated specimen is subjected to bidirectional compressive force, the adjusting cylinders in the two side support components are set opposite to each other; when the simulated specimen is subjected to shear force, the compressive force applied to the specimen by the two adjusting cylinders is staggered; when the simulated specimen is subjected to tensile force, the adjusting cylinder is located at the end where the adjusting slider abuts against the specimen. S4: Sealed protective cover, adjust the loading stage to make the sample correspond to the loading system, input the set parameters into the test instrument base, and plan the indentation dot matrix on the sample surface. S5: The corresponding telescopic cylinder and adjusting cylinder are activated to apply compressive force, shear force or tensile force to the sample; the loading system is adjusted to dynamically load the sample according to the planned indentation lattice; S6: After the test is completed, open the protective cover, unload the sample, and adjust the mechanical testing device to reset.

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