CN106526241A - In-situ loading device based on scanning electron microscope - Google Patents

Abstract

The invention discloses an in-situ loading device based on a scanning electron microscope, comprising: a test bench; a first clamping block, a second clamping block; a first connecting block, a second connecting block, the first connecting block and the first clamping block The holding block is arranged oppositely, the second connecting block is arranged opposite to the second clamping block; the piezoelectric ceramic group is arranged between the first connecting block and the first clamping block; the pressure sensor is arranged between the second connecting block and the second clamping block Between the second clamping blocks; screw transmission mechanism, which is used to make the first connecting block and the second connecting block move relatively, so that the first clamping block and the second clamping block clamp the test piece, and press The electro-ceramic combination and the pressure sensor measure the mechanical data of the test piece; the gearbox is connected with the screw drive mechanism and used to drive the screw drive mechanism; the actuator is used to drive the gearbox. Through the screw drive mechanism, the first clamping block and the second clamping block can quickly approach the test piece and load the test piece, thereby shortening the time for loading the test piece.

Description

SEM-based in-situ loading device

technical field

The invention relates to the technical field of electromechanical control, in particular to an in-situ loading device based on a scanning electron microscope.

Background technique

The macro damage of materials is often caused by the accumulation of micro failures. For example, the damage of metal polycrystalline materials often starts from grain boundary fracture. In addition, the research on the macro mechanical properties of macro materials has been relatively mature. At present, relevant scholars will research the field of view Gradually turned to the study of micro-scale mechanical properties of materials, which inevitably involves the problem of micro-deformation measurement. The key to realizing microscopic deformation measurement is to improve the spatial resolution and displacement sensitivity of measurement. In recent years, the development of high-resolution microscopy technology, especially the scanning electron microscope, has provided unprecedented development opportunities for micro-nano experimental mechanical measurement technology, and its spatial resolution is as high as nanometers. The use of scanning electron microscopy for mechanical property characterization requires the development of corresponding loading equipment.

However, the loading mechanism used to load the test piece in the prior art is a micro-feed loading mechanism, that is, the feeding speed is the same during the process of approaching and loading the test piece, and the speed is low, which will inevitably prolong the operation time of the loading test (A reasonable loading mechanism is to feed fast when approaching the specimen, and to feed slowly when loading the specimen).

Contents of the invention

In view of the above-mentioned technical problems existing in the prior art, the implementation of the present invention provides an in-situ loading device based on a scanning electron microscope that can solve one or more of the above-mentioned problems.

In order to solve the problems of the technologies described above, the technical solution adopted in the present invention is:

A scanning electron microscope-based in-situ loading device for loading a specimen, comprising:

Test Bench;

a first clamping block and a second clamping block; both are relatively arranged on the test bench for clamping the test piece;

a first connecting block and a second connecting block, the first connecting block is arranged opposite to the first clamping block, and the second connecting block is arranged opposite to the second clamping block;

a piezoelectric ceramic group disposed between the first connection block and the first clamping block;

a pressure sensor disposed between the second connection block and the second clamping block;

screw drive mechanism, which is used to make the first connecting block and the second connecting block move relatively, so that the first clamping block and the second clamping block clamp the test piece, and pass the pressure The electroceramic combination and the pressure sensor measure the mechanical data of the test piece;

A gearbox, which is connected to the screw drive mechanism and used to drive the screw drive mechanism;

an actuator for driving the gearbox.

Preferably, it also includes:

a sealed flange, in which data lines are housed, and the data lines are respectively electrically connected to the actuator, the piezoelectric ceramic group, and the pressure sensor;

a control box, which is electrically connected to the data line in the sealed flange, and is used to collect the physical and mechanical data of the actuator, the piezoelectric ceramic group and the pressure sensor;

A computer, which is electrically connected to the control box, is used to display the physical and mechanical data collected by the control box, and analyze the physical and mechanical data.

Preferably, a grating displacement meter is also included, the grating displacement meter is arranged on the test bench and extends along the clamping direction of the first clamping block and the second clamping block to detect the The amount of compression of the piece.

Preferably, the gearbox is connected to the screw drive mechanism through a coupling.

Preferably, the piezoelectric ceramic group is formed by splicing a plurality of piezoelectric ceramic blocks side by side, and the two sides of the piezoelectric ceramic group are respectively fixed by a first piezoelectric ceramic fixing device and a second piezoelectric ceramic fixing device.

Compared with the prior art, the beneficial effect of the in-situ loading device based on the scanning electron microscope of the present invention is: through the screw drive mechanism, the first clamping block and the second clamping block can quickly approach the test piece and carry out the test on the test piece. loading, thereby shortening the loading time of the specimen.

Description of drawings

FIG. 1 is a schematic structural view of an in-situ loading device based on a scanning electron microscope of the present invention.

Fig. 2 is a structural schematic diagram of the hydraulic servo mechanism of the in-situ loading device based on the scanning electron microscope of the present invention.

In the picture:

1-test bench 1; 2-actuator; 3-grating displacement meter; 4-gearbox; block; 10-coupling; 11-sealing flange; 12-control box; 13-computer; 14-pressure sensor; 15-piezoelectric ceramic group; 16-first clamping block; 17-second clamping Block; 18-test piece; 19-second servo cylinder; 20-second servo piston; 21-second chamber; 22-first chamber; 23-second servo spring; 24-first servo cylinder; 25 - first servo piston; 26 - rodless cavity; 27 - rod cavity; 28 - first servo spring; 29 - first servo piston rod.

detailed description

In order to enable those skilled in the art to better understand the technical solutions of the present invention, the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

The embodiment of the present invention discloses a scanning electron microscope-based in-situ loading device for loading a test piece 18. The in-situ loading device includes: a test bench 1, a first clamping block 16, a second clamping block 17, Piezoelectric ceramic group 15, pressure sensor 14, lead screw 7 transmission mechanism, gearbox 4, actuator 2, sealing flange 11, control box 12, computer 13 and grating displacement meter 3. The pressure test bench is used to carry and install the above-mentioned parts; the first clamping block 16 and the second clamping block 17 are relatively arranged on the test bench 1 for clamping the test piece 18; the first connecting block 9 and the first The clamping block 16 is arranged oppositely, and the second connecting block 8 is arranged opposite to the second clamping block 17; the piezoelectric ceramic group 15 is arranged between the first connecting block 9 and the first clamping block 16; the piezoelectric ceramic group 15 is arranged between the first connecting block 9 and the first clamping block 16; the transmission mechanism of the lead screw 7 is driven by the gearbox 4 to drive the relative movement of the first connecting block 9 and the second connecting block 8, and through the piezoelectric ceramic group 15 and the pressure sensor 14 to make the relative movement of the first clamping block 16 and the second clamping block 17 to clamp the test piece 18, the pressure of the test piece 18 is measured by the piezoelectric ceramic group 15 and the pressure sensor 14; the actuator 2 is used to drive the gearbox 4 to provide power and movement for loading; the grating displacement meter 3 is arranged on the test bench 1 and extends along the clamping direction of the first clamping block 16 and the second clamping block 17 to detect the test piece 18 compression. The sealing flange 11 accommodates data lines, and the data lines are respectively electrically connected to the actuator 2, the piezoelectric ceramic group 15 and the pressure sensor 14; the control box 12 is electrically connected to the data lines in the sealing flange 11 for Collect the physical and mechanical data of the actuator 2, the piezoelectric ceramic group 15 and the pressure sensor 14, such as the rotational speed of the actuator 2, the pressure and displacement data of the test piece 18; the computer 13 is electrically connected with the control box 12 for displaying Control the physical and mechanical data collected by the box 12, and analyze the physical and mechanical data. In this way, the first clamping block 16 and the second clamping block 17 can quickly approach the test piece 18 and load the test piece 18 through the screw drive mechanism, thereby shortening the time for loading the test piece 18 .

Preferably, the gearbox 4 is connected to the screw drive mechanism through a coupling 10 .

Preferably, the piezoelectric ceramic group 15 is formed by splicing a plurality of piezoelectric ceramic blocks side by side, and the two sides of the piezoelectric ceramic group 15 are respectively fixed by a first piezoelectric ceramic fixing device and a second piezoelectric ceramic fixing device.

The actuator 2 can be a motor with adjustable speed. When the motor drives the first connecting block 9 and the second connecting block 8 through the transmission mechanism of the gearbox 4 and the lead screw 7, to drive the first clamping block 16 and the second clamping block After the block 17 quickly approaches and touches the test piece 18 through the pressure sensor 14, the pressure sensor 14 controls the motor speed to decrease through the control box 12 to reduce the feed speed of the test piece 18, thereby realizing slow loading.

However, although the sensor can accurately measure the pressure of the test piece 18, and can feed back to the control box 12 in real time, the control of the control box 12 is not accurate when controlling the speed of the motor, that is, when the pressure sensor 14 measures The resulting pressure suddenly increases, indicating that when the motor speed is too high, the pressure is fed back to the control box 12, and the control box 12 can only control the reduction of the motor speed, but it cannot predict and calculate how fast the motor speed can be reduced to make the test piece 18 Uniform loading, often under the control of the control box 12, the motor speed decreases, so that the loading pressure of the test piece 18 is lower than the pressure required for uniform loading, so that the loading pressure fluctuates continuously.

In order to solve the above problems, the actuator 2 is preferably a variable displacement hydraulic motor, specifically, the screw 7 transmission mechanism includes a screw 7 and a screw body 5 for forming a screw transmission with the screw; the hydraulic motor and the first A hydraulic servo mechanism is arranged between the connecting block 9 and the second connecting block 8; one end of the lead screw 7 is installed on the output shaft of the gearbox 4, and the other end is installed on the bearing seat 6; the hydraulic servo mechanism includes a first servo cylinder 24 and the second servo cylinder 19, the first servo cylinder 24 is provided with a first servo piston 25, the first servo piston 25 is provided with a first servo piston rod 29, and the first servo piston rod 29 stretches out of the first servo cylinder 24 It is connected with the swash plate of the hydraulic motor to adjust the inclination angle of the swash plate. The first servo spring 28 is arranged in the rod chamber 27 of the first servo cylinder 24; the thread matrix 5 is arranged in the second servo cylinder 19, and the thread matrix 5 The two ends extend out of the second servo cylinder 19 respectively, and the outer periphery of the middle part of the silk matrix 5 forms a second servo piston 20 to divide the second servo cylinder 19 into a first chamber 22 and a second chamber 21. A second servo spring 23 is provided, and a thread hole is provided on the axial direction of the thread matrix 5 for threading the threaded screw 7, and the threaded screw 7 passes through the thread hole to form a screw transmission with the thread matrix 5; the first connecting block 9 and the second connection block 8 are respectively arranged on the cylinder bodies of two second servo cylinders 19; the first chamber 22 of the second servo cylinder 19 communicates with the rodless chamber 26 of the first servo cylinder 24, and the second servo cylinder 19 The second chamber 21 of the first servo cylinder 24 communicates with the rod cavity 27 of the first servo cylinder 24, and the telescopic action of the first servo piston rod 29 and the inclination angle of the swash plate of the hydraulic motor are set to: when the first servo piston rod 29 stretches out When the displacement increases, the inclination angle of the swash plate decreases, the displacement of the hydraulic motor decreases, and the reduction of the displacement of the hydraulic motor makes the motor speed decrease while the output torque remains unchanged. When the extension of the first servo piston rod 29 decreases Hours, the inclination angle of the swash plate increases, the displacement of the hydraulic motor increases, and the increase of the displacement of the hydraulic motor makes the rotational speed of the motor increase while the output torque remains unchanged. In this way, when the first clamping block 16 and the second clamping block 17 are in contact with the test piece 18, the first clamping block 16 and the second clamping block 17 pressurize the test piece 18, and the test piece 18 presses the first clamping block. The reaction force of the holding block 16 and the second clamping is transmitted to the second servo cylinder 19 through the first clamping block 16 and the second clamping block 17, the first connecting block 9 and the second connecting block 8, and the second servo cylinder The hydraulic oil pressure in the first chamber 22 in 19 rises, so that the hydraulic oil in the rodless chamber 26 of the first servo cylinder 24 rises, and the hydraulic oil in it pushes against the first servo piston 25 so that the first servo The protruding amount of the piston rod 29 increases, so that the inclination angle of the slope of the hydraulic motor is smaller, thereby reducing the displacement of the hydraulic motor and reducing the rotating speed. The torque of the hydraulic motor is constant) and the moving speeds of the first connecting block 9 and the second connecting block 8 and the first clamping block 16 and the second clamping block 17 are reduced, so that the first clamping block 16 and the second clamping block 17 The second clamping block 17 slowly and evenly pressurizes the test piece 18. When the hydraulic motor makes the moving speed of the first clamping block 16 and the second clamping block 17 too small and the pressure drops, the first chamber 22 And the pressure in the rodless chamber 26 becomes smaller, the protruding amount of the first servo piston rod 29 becomes smaller, and the displacement of the hydraulic motor begins to increase, thereby increasing the moving speed of the first clamping block 16 and the second clamping block 17 Large, so as to meet the conditions of slow and uniform pressure.

In this embodiment, the present invention uses the feedback of the hydraulic oil pressure in the hydraulic system to adjust the speed of the first clamping block 16 and the second clamping block 17 to achieve slow and uniform pressure, so that the accurate and true pressure of the test piece 18 can be obtained. mechanical data without prolonging the duration of the loading test.

The above embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and the protection scope of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent replacements to the present invention within the spirit and protection scope of the present invention, and such modifications or equivalent replacements should also be deemed to fall within the protection scope of the present invention.

Claims (5)

1. a kind of in-situ loading device based on scanning electron microscope, is used for loading test piece, is characterized in that, comprises: Test Bench; a first clamping block and a second clamping block; both are relatively arranged on the test bench for clamping the test piece; a first connecting block and a second connecting block, the first connecting block is arranged opposite to the first clamping block, and the second connecting block is arranged opposite to the second clamping block; a piezoelectric ceramic group disposed between the first connection block and the first clamping block; a pressure sensor disposed between the second connection block and the second clamping block; screw drive mechanism, which is used to make the first connecting block and the second connecting block move relatively, so that the first clamping block and the second clamping block clamp the test piece, and pass the pressure The electroceramic combination and the pressure sensor measure the mechanical data of the test piece; A gearbox, which is connected to the screw drive mechanism and used to drive the screw drive mechanism; an actuator for driving the gearbox. 2. The in-situ loading device based on the scanning electron microscope according to claim 1, further comprising: a sealed flange, in which data lines are housed, and the data lines are respectively electrically connected to the actuator, the piezoelectric ceramic group, and the pressure sensor; a control box, which is electrically connected to the data line in the sealed flange, and is used to collect the physical and mechanical data of the actuator, the piezoelectric ceramic group and the pressure sensor; A computer, which is electrically connected to the control box, is used to display the physical and mechanical data collected by the control box, and analyze the physical and mechanical data. 3. The in-situ loading device based on the scanning electron microscope according to claim 1, further comprising a grating displacement meter, the grating displacement meter is arranged on the test bench, and along the first clamping block and the clamping direction of the second clamping block are extended to detect the compression amount of the test piece. 4. The scanning electron microscope-based in-situ loading device according to claim 1, wherein the gearbox is connected to the screw drive mechanism through a coupling. 5. The in-situ loading device based on a scanning electron microscope according to claim 1, wherein the piezoelectric ceramic group is formed by splicing a plurality of piezoelectric ceramic blocks side by side, and the two sides of the piezoelectric ceramic group are respectively It is fixed by the first piezoelectric ceramic fixing device and the second piezoelectric ceramic fixing device.