CN109781760A - A miniature multifunctional in-situ test bench based on SEM electron microscope - Google Patents

Abstract

The invention discloses a kind of miniature multi-function in-situ test platform based on SEM Electronic Speculum, including bottom plate, and the motor, screw rod etc. in setting portion in the soleplate；Gear set is provided in gear-box, the output shaft of motor is connected with the input shaft of gear set, and the output shaft of gear set is connected with screw rod, and the thread rotary orientation on screw rod both sides is opposite；There are two sliding blocks for setting on sliding rail；Loading board and fixture post-erection plate are threadedly coupled with the middle part of screw rod before fixture, and loading board and fixture post-erection plate are individually fixed on two groups of sliding blocks before fixture, displacement sensor is additionally provided with before fixture in loading board, force snesor is additionally provided in rear slider fixed plate, displacement sensor movable shaft is contacted with force snesor, for measuring the relative displacement between front-slider fixed plate and rear slider fixed plate；When test, test specimen be arranged before fixture loading board and fixture post-erection plate, screw rod move when so that front-slider fixed plate and rear slider fixed plate it is close to each other perhaps separate achieve the purpose that test specimen load or unload.

Description

A miniature multifunctional in-situ test bench based on SEM electron microscope

technical field

The invention relates to a miniature multifunctional in-situ test bench based on an SEM electron microscope, which is suitable for a micro loading test in the SEM electron microscope, and includes loading methods such as tension, compression, three-point bending, four-point bending and shearing, etc. Observation and measurement of microscopic changes at the same position under loading mode.

Background technique

Scanning electron microscope (SEM) is a microscopic morphology observation method between transmission electron microscope and optical microscope, which can directly use the material properties of material surface materials for microscopic imaging. Moreover, the scanning electron microscope has a high magnification, which can be adjusted from 200,000 to 200,000 times; and has a large depth of field and a wide field of view, which can directly observe the fine structure of the uneven surface of various specimens.

Engineering structural materials will encounter a variety of mechanical environments during the service process, such as fatigue loading environment, force impact environment, bending loading environment and torsional shear loading environment, etc., and fully understand the mechanical properties of engineering structural materials in various mechanical environments. It is very important for structural safety life design and structural strength stiffness design. Therefore, the loading table must be used to simulate the mechanical environment of engineering structural materials in service and carry out mechanical experiments.

In summary, miniaturizing the loading device and integrating it into the SEM cavity to realize real-time observation of the microscopic changes on the surface of the engineering structural material under loading is of great help for understanding the properties of the material itself.

SUMMARY OF THE INVENTION

In order to solve the above problems, the present invention provides a miniature multifunctional in-situ test bench based on SEM electron microscope, which has the advantages of simulating various mechanical loading environments, large force loading range, adjustable loading speed, and can realize microscopic observation of the same position. With the characteristics of measurement, it can meet the real-time in-situ measurement of engineering structural materials under multiple loads.

The present invention adopts the following technical scheme to realize:

A miniature multifunctional in-situ test bench based on SEM electron microscope, comprising a base plate, an electron microscope fixing plate arranged at one end of the base plate, a gear box and a side plate of the gear box at the other end, and a motor, a slide rail group, and a copper plate arranged in the middle of the base plate. Nut, lead screw, slider and clamp set; of which,

The gear box is provided with a gear set, the output shaft of the motor is connected with the input shaft of the gear set, the output shaft of the gear set is connected with one end of the screw rod, and the other end of the screw rod is connected with the screw stopper set on the bottom plate near the electron microscope fixing plate The plate is flexibly connected, and the threads on both sides of the screw are in opposite directions;

The slide rail set includes two slide rails that are symmetrically arranged and parallel to the lead screw, and two sliders are arranged on the slide rails; the fixture set includes the test piece and the corresponding fixture front loading plate and fixture rear loading plate, and the fixture front loading plate and the rear mounting plate of the fixture are respectively connected with the middle part of the screw through the copper nut, and the front mounting plate of the fixture and the rear mounting plate of the fixture are respectively fixed on two sets of sliders, the front mounting plate of the fixture is also provided with a displacement sensor, the rear slider A force sensor is also arranged on the fixed plate, and the movable shaft of the displacement sensor is in contact with the force sensor to measure the relative displacement between the front slider fixed plate and the rear slider fixed plate;

During the test, the specimen is set on the front mounting plate of the fixture and the rear mounting plate of the fixture. When the screw moves, the front sliding block fixing plate and the rear sliding block fixing plate are close to or away from each other, so as to achieve the purpose of loading or unloading the specimen.

A further improvement of the present invention is that it also includes a sleeve, and the output shaft of the gear set is connected to one end of the screw rod through the sleeve.

A further improvement of the present invention is that the clamp group is a four-point bending clamp group, including a four-point bending clamp front mounting plate, a four-point bending clamp rear mounting plate, a four-point bending steel column and a four-point bending test piece; The number of steel columns is four. During the test, the four-point bending specimens are set between the front loading plate of the four-point bending fixture and the rear loading plate of the four-point bending fixture. Set on both sides of the four-point bending specimen.

A further improvement of the present invention lies in that the clamp group is a three-point bending clamp group, including a three-point bending clamp front mounting plate, a three-point bending clamp rear mounting plate, a three-point bending steel column and a three-point bending test piece; The number of steel columns is three. During the test, the three-point bending specimen is set between the front loading plate of the three-point bending fixture and the rear loading plate of the three-point bending fixture, and two of the three three-point bending steel columns are set at the three-point bending fixture. One side of the point bending specimen, and the third one is set on the other side of the three-point bending specimen.

A further improvement of the present invention lies in that the clamp group is a tension clamp group, including a tension clamp front plate, a tension clamp rear plate and a tension test piece; during the test, the tension test piece is arranged on the tension clamp front plate and the rear loading plate of the stretching fixture, and its two ends are respectively connected with the front loading plate of the stretching fixture and the rear loading plate of the stretching fixture.

A further improvement of the present invention lies in that the clamp group is a compression clamp group, including a compression clamp front mounting plate, a compression clamp rear mounting plate and a compression test piece; during the test, the compression test piece is arranged on the compression fixture front mounting plate and the compression fixture rear mounting plate between them, and respectively contact with the front loading plate of the compression fixture and the rear loading plate of the compression fixture.

A further improvement of the present invention is that the clamp group is a shear clamp group, including a shear clamp front plate, a shear clamp rear plate, a shear disc and a shear specimen; during the test, the shear specimen passes through the shear disc. Set between the front loading plate of the shearing fixture and the rear loading plate of the shearing fixture.

The present invention has following beneficial technical effect:

1. The structure size is small, the overall size is 164×82×32mm, which can not only meet the requirements of SEM electron microscope cavity use, but also meet the use requirements of other observation equipment such as transmission electron microscope, Raman spectrometer and X-ray diffractometer.

2. There are various loading methods. The present invention provides five types of fixtures, which can realize the loading of tension, compression, three-point bending, four-point bending and shearing, so it can simulate different mechanical environments, such as fatigue loading environment. , force impact environment, bending loading environment and torsional shear loading environment, etc., fully meet the requirements of engineering structural materials for experimental conditions under different service conditions.

3. The force loading range is large. The in-situ test bench provided by the present invention can meet the maximum axial force loading of 1000N. Compared with the force loading bench of the same size, its range is increased by at least 0.5 times.

Description of drawings

FIG. 1 is an overall view of the present invention.

Figure 2 is an overall view with the loading device and the force sensor removed.

FIG. 3 is an overall view of FIG. 2 with the gearbox removed.

Figure 4 is an overall view of the four-point bending clamp set.

Figure 5 is an overall view of the three-point bending clamp set.

Fig. 6 is an overall view of the tension jig set.

Figure 7 is an overall view of the compression clamp set.

Fig. 8 is an overall view of the shear jig set.

Reference numerals indicate:

1 is the bottom plate, 2 is the electron microscope fixing plate, 3 is the side plate of the gearbox, 4 is the gearbox, 5 is the motor, 6 is the displacement sensor, 7 is the force sensor, 8 is the slide rail group, 9 is the screw baffle, 10 11 is the rear mounting plate of the fixture, 12 is the steel column, 13 is the test piece, 14 is the front sliding block fixing plate, 15 is the rear sliding block fixing plate, 16 is the copper nut, 17 is the lead screw, 18 For the slider, 19 for the sleeve, 20 for the gear set.

Among them, there are five kinds of fixture groups, namely:

Four-point bending fixture group: 10-a is the four-point bending fixture front mounting plate, 11-a is the four-point bending fixture rear mounting plate, 12-a is the four-point bending steel column, and 13-a is the four-point bending specimen;

Three-point bending fixture group: 10-b is the front mounting plate of the three-point bending fixture, 11-b is the three-point bending fixture rear mounting plate, 12-b is the three-point bending steel column, and 13-b is the three-point bending specimen;

Tensile fixture group: 10-c is the front plate of the tensile fixture, 11-c is the rear plate of the tensile fixture, and 13-c is the tensile specimen;

Compression fixture group: 10-d is the front mounting plate of the compression fixture, 11-d is the rear mounting plate of the compression fixture, and 13-d is the compression specimen;

Shearing fixture group: 10-f is the front mounting plate of the shearing fixture, 11-f is the rear mounting plate of the shearing fixture, 12-f is the shearing disc, and 13-f is the shearing specimen.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and embodiments.

As shown in FIGS. 1 to 3 , a miniature multi-purpose in-situ test bench based on SEM electron microscope provided by the present invention includes a bottom plate 1, an electron microscope fixing plate 2, a gear box side plate 3, a gear box 4, a motor 5, a displacement Sensor 6, Force Sensor 7, Slide Rail Set 8, Screw Baffle 9, Fixture Front Mounting Plate 10, Fixture Back Mounting Plate 11, Steel Column 12, Specimen 13, Front Slider Fixing Plate 14, Rear Slider Fixing Plate 15. Copper nut 16, screw 17, slider 18, sleeve 19 and gear set 20.

The main body of the test bench is a frame composed of a bottom plate 1 , an electron microscope fixing plate 2 , a gear box side plate 3 and a gear box 4 , which are connected with each other by M3 screws. Moreover, the test bench can be fixed in the SEM electron microscope cavity through the electron microscope fixing plate 2 .

The main body of the test bench is made of 6061 aluminum plate.

The transmission mechanism of the test bench consists of a motor 5, a slide rail group 8, a front slider fixing plate 14, a rear slider fixing plate 15, a copper nut 16, a screw 17, a slider 18 and a gear group 20. The motor 5 is fixed to the gear on the side plate 3 of the box, and the motor shaft is connected with the gear set 20 to drive the gear set 20 to rotate. The gear set 20 is fixed on the gear box side plate 3 and the gear box 4 , and is driven by the motor 5 and then drives the screw rod 17 to rotate through the sleeve 19 . Both ends of the screw rod 17 are fixed on the screw baffle plate 9 and the gear box 4 through bearings, and the middle part of the screw rod 17 is respectively fixed on the front slider fixing plate 14 and the rear slider fixing plate 15 through copper nuts 16 . The front slider fixing plate 14 and the rear slider fixing plate 15 are respectively fixed on the two sets of sliders 18 to facilitate horizontal movement. The screw threads on both sides of the screw rod 17 are rotated in opposite directions. When the screw rod 17 moves, the front slider fixing plate 14 and the rear slider fixing plate 15 approach or move away from each other to achieve the purpose of loading or unloading.

The data acquisition module of the test bench includes a displacement sensor 6 and a force sensor 7 . The displacement sensor 6 is fixed to the front slider fixing plate 14 by M2 screws, and the movable shaft of the displacement sensor is in contact with the force sensor 7 to measure the relative displacement between the front slider fixing plate 14 and the rear slider fixing plate 15 . The force sensor 7 is fixed on the rear slider fixing plate 15. The principle of force measurement of the force sensor 7 is that the strain of the four resistance strain gauges constituting the Wheatstone bridge is proportional to the applied force. Through the displacement sensor 6 and the force sensor 7, the relationship between the load and the displacement of the test piece 13 can be obtained.

There are five types of fixture sets in the test bench, corresponding to five different loading methods: tension, compression, three-point bending, four-point bending and shearing. Each clamp group is fixed on the slider fixing plate by M3 or M4 screws. By selecting different fixture groups, different loading forms can be completed to suit different test requirements.

As shown in Figure 4, the fixture group is a four-point bending fixture group, including a four-point bending fixture front mounting plate 10-a, a four-point bending fixture rear mounting plate 11-a, a four-point bending steel column 12-a and a four-point bending fixture Specimen 13-a; wherein, the number of four-point bending steel columns 12-a is four. During the test, the four-point bending specimen 13-a is set on the front mounting plate 10-a of the four-point bending fixture and the four-point bending fixture Between the rear mounting plates 11-a, four four-point bending steel columns 12-a are arranged in groups of two, respectively, on both sides of the four-point bending test piece 13-a.

As shown in Figure 5, the fixture group is a three-point bending fixture group, including a three-point bending fixture front mounting plate 10-b, a three-point bending fixture rear mounting plate 11-b, a three-point bending steel column 12-b and a three-point bending fixture Specimen 13-b; among them, the number of three-point bending steel columns 12-b is three. During the test, the three-point bending specimen 13-b is set on the front loading plate 10-b of the three-point bending fixture and the three-point bending fixture Between the rear mounting plates 11-b, two of the three three-point bending steel columns 12-b are arranged on one side of the three-point bending specimen 13-b, and the third one is arranged on the other side of the three-point bending specimen 13-b. side.

As shown in Figure 6, the fixture group is a tensile fixture group, including a front loading plate 10-c of the tensile fixture, a rear loading plate 11-c of the tensile fixture, and a tensile specimen 13-c; during the test, the tensile specimen 13-c is arranged between the front loading board 10-c of the stretching fixture and the rear loading board 11-c of the stretching fixture, and its two ends are respectively connected to the front loading board 10-c of the stretching fixture and the rear loading board 11-c of the stretching fixture. -c is connected.

As shown in Fig. 7, the clamp group is a compression clamp group, including a compression clamp front mounting plate 10-d, a compression clamp rear mounting plate 11-d and a compression specimen 13-d; during the test, the compression specimen 13-d is set in the The compression fixture front mounting plate 10-d and the compression fixture rear mounting plate 11-d are in contact with the compression fixture front mounting plate 10-d and the compression fixture rear mounting plate 11-d, respectively.

As shown in Figure 8, the clamp group is a shearing clamp group, including a shearing fixture front mounting plate 10-f, a shearing fixture rear mounting plate 11-f, a shearing disc 12-f and a shearing specimen 13-f; During the test, the shearing specimen 13-f is set between the shearing fixture front mounting plate 10-f and the shearing fixture rear mounting plate 11-f through the shearing disc 12-f.

The using method of the present invention is as follows:

Step 1. Visually check whether the components of the test bench are in good condition, manually check whether the fixing of each component is loose, whether the electrical circuit is complete, and whether there is a short circuit or open circuit. If there are no problems, complete the device security check.

Step 2: Turn on the power of the test bench, start the motor, and observe whether the motor is in good condition and whether the displacement of the fixture group is linear. If it is in good condition, assemble the corresponding fixture group, control the motor to rotate, and make the loading table reach the state to be loaded.

Step 3: Clear the control device, place the test piece in the fixture group, control the motor, and make the fixture clamp the test piece. Then the test bench is placed in the SEM electron microscope cavity to complete the placement of the test bench.

Step 4: Start the test, load and unload the test piece through the control device, and observe the microscopic changes of the test piece through the electron microscope.

Step 5. After the test is completed, open the electron microscope cavity, take out the loading table, control the motor to unload, remove the test piece, and return the test table to its original position.

Claims (7)

1. A micro multifunctional in-situ test bed based on an SEM (scanning electron microscope) is characterized by comprising a bottom plate (1), an electron microscope fixing plate (2) arranged at one end of the bottom plate (1), a gear box (4) and a gear box side plate (3) arranged at the other end of the bottom plate, and a motor (5), a sliding rail group (8), a copper nut (16), a lead screw (17), a sliding block (18) and a clamp group which are arranged in the middle of the bottom plate (1); wherein,

a gear set (20) is arranged in the gear box (4), an output shaft of the motor (5) is connected with an input shaft of the gear set (20), an output shaft of the gear set (20) is connected with one end of a screw rod (17), the other end of the screw rod (17) is movably connected with a screw rod baffle plate (9) which is arranged on the bottom plate (1) and close to the electron microscope fixing plate (2), and the rotating directions of threads on two sides of the screw rod (17) are opposite;

the slide rail group (8) comprises two slide rails which are symmetrically arranged and parallel to the screw rod (17), and two slide blocks (18) are arranged on the slide rails; the fixture group comprises a test piece (13), a fixture front mounting plate (10) and a fixture rear mounting plate (11) which are matched for use, the fixture front mounting plate (10) and the fixture rear mounting plate (11) are respectively in threaded connection with the middle of a lead screw (17) through a copper nut (16), the fixture front mounting plate (10) and the fixture rear mounting plate (11) are respectively fixed on two groups of sliders (18), a displacement sensor (6) is further arranged on the fixture front mounting plate (10), a force sensor (7) is further arranged on a rear slider fixing plate (15), and a movable shaft of the displacement sensor is in contact with the force sensor (7) and is used for measuring relative displacement between the front slider fixing plate (14) and the rear slider fixing plate (15);

during the test, the test piece (13) is arranged on the front clamp mounting plate (10) and the rear clamp mounting plate (11), and when the screw rod (17) moves, the front slider fixing plate (14) and the rear slider fixing plate (15) are close to or far away from each other, so that the purpose of loading or unloading the test piece (13) is achieved.

2. The in-situ test bench for micro multifunction based on SEM electron microscope according to claim 1, further comprising a sleeve (19), wherein the output shaft of the gear set (20) is connected with one end of the screw rod (17) through the sleeve (19).

3. The SEM electron microscope-based miniature multifunctional in-situ test bed is characterized in that the fixture set is a four-point bending fixture set and comprises a four-point bending fixture front mounting plate (10-a), a four-point bending fixture rear mounting plate (11-a), four-point bending steel columns (12-a) and a four-point bending test piece (13-a); the four-point bending steel columns (12-a) are four in number, during testing, four-point bending test pieces (13-a) are arranged between a four-point bending clamp front mounting plate (10-a) and a four-point bending clamp rear mounting plate (11-a), and two of the four-point bending steel columns (12-a) are arranged on two sides of the four-point bending test pieces (13-a) in a group.

4. The in-situ test bench for micro multifunctional functions based on SEM electron microscope according to claim 1, wherein the fixture set is a three-point bending fixture set comprising a three-point bending fixture front mounting plate (10-b), a three-point bending fixture rear mounting plate (11-b), a three-point bending steel column (12-b) and a three-point bending test piece (13-b); the three-point bending test device comprises three-point bending steel columns (12-b), during test, three-point bending test pieces (13-b) are arranged between a front mounting plate (10-b) of a three-point bending clamp and a rear mounting plate (11-b) of the three-point bending clamp, two of the three-point bending steel columns (12-b) are arranged on one side of the three-point bending test pieces (13-b), and the third three-point bending steel columns are arranged on the other side of the three-point bending test pieces (13-b).

5. The in-situ test bench for micro multifunction based on SEM electron microscope according to claim 1, wherein the fixture set is a tensile fixture set, comprising a tensile fixture front mounting plate (10-c), a tensile fixture rear mounting plate (11-c) and a tensile test piece (13-c); during testing, the tensile test piece (13-c) is arranged between the front mounting plate (10-c) of the tensile clamp and the rear mounting plate (11-c) of the tensile clamp, and two ends of the tensile test piece are respectively connected with the front mounting plate (10-c) of the tensile clamp and the rear mounting plate (11-c) of the tensile clamp.

6. The SEM electron microscope-based miniature multifunctional in-situ test bed is characterized in that the clamp group is a compression clamp group and comprises a compression clamp front mounting plate (10-d), a compression clamp rear mounting plate (11-d) and a compression test piece (13-d); during testing, the compression test piece (13-d) is arranged between the compression clamp front mounting plate (10-d) and the compression clamp rear mounting plate (11-d) and is respectively contacted with the compression clamp front mounting plate (10-d) and the compression clamp rear mounting plate (11-d).

7. The SEM electron microscope-based miniature multifunctional in-situ test bed is characterized in that the clamp group is a shearing clamp group and comprises a shearing clamp front mounting plate (10-f), a shearing clamp rear mounting plate (11-f), a shearing disc (12-f) and a shearing test piece (13-f); during the test, the shearing test piece (13-f) is arranged between the front mounting plate (10-f) of the shearing clamp and the rear mounting plate (11-f) of the shearing clamp through the shearing disc (12-f).