CN103364281A - Material mechanical property in-situ three-point bending test platform with adjustable test environment temperature - Google Patents

Abstract

The invention relates to an in-situ three-point bending test platform for material mechanical properties with adjustable testing environment temperature, belonging to the field of in-situ mechanical property testing. It heats the test piece through the resistance wire, combined with the observation of the high-magnification solid-state CCD industrial imaging lens, it can dynamically monitor the change of the microstructure of the material under the action of bending load at different ambient temperatures, as well as the micromechanics of crack initiation and expansion. Behavior. The invention is mainly composed of a precision drive transmission unit, a detection unit, an imaging system unit, a temperature field control unit, and an auxiliary support unit. The advantages are: simple and compact structure, stable transmission, effective combination of temperature field and stress field, under the high-resolution imaging system, the microscopic deformation, damage and fracture process of materials can be observed in situ, in order to reveal the material under different temperature fields The mechanical properties and damage mechanism provide a new test method.

Description

In-situ three-point bending test platform for material mechanical properties with adjustable test environment temperature

technical field

The invention relates to the field of in-situ mechanical property testing, and relates to an in-situ three-point bending test platform for material mechanical properties with adjustable test environment temperature. In different temperature fields, the high-magnification solid-state CCD industrial imaging system can be used to dynamically observe the microstructure, lattice changes, crack initiation, expansion and fracture of the test material in real time. The mechanical property testing device provides a brand-new method for testing the mechanical properties of materials based on the temperature field.

Background technique

In-situ mechanical performance testing refers to the process of testing the mechanical properties of specimen materials at the micro/nano scale. Microscopic imaging systems such as atomic force microscopes, electron microscopes, and optical microscopes can be used to analyze the microscopic properties of materials under various loads. A mechanical testing method for real-time online observation of deformation, tissue morphology and crack damage. This technology can analyze the mechanical behavior and damage mechanism of various materials and their products under various loads from the microscopic level. In the category of many micro-nano mechanical performance tests, parameters such as elastic modulus, shear modulus, hardness, yield limit, and fracture limit are the most important test objects in the mechanical property test of micro-components. Various mechanical parameters have been produced for these mechanical properties. Test methods such as tension/compression, bending, shear, torsion, nanoindentation/scratch and tympanic membrane etc. Among them, the in-situ three-point bending test method can comprehensively reflect the mechanical properties of materials or products under bending conditions, and plays an important role in the testing process of various materials. It is mainly manifested in that the loading device is relatively simple, the processing technology requirements for the bending test piece are relatively low, and there are no problems such as harsh centering and clamping. The process obtains a more intuitive deformation effect.

With the rapid development of the modern aerospace industry and the rapid rise of new high-tech products such as aviation rockets, aviation missiles, and aviation aircraft, the research, development and testing technology of new high-temperature composite materials has attracted more and more attention in the fields of scientific research and industrial manufacturing. . Based on the urgent demand for high temperature in the aerospace industry, one of the new material explorations in the future is to use multi-particle beam physical vapor deposition or multi-particle evaporation technology to combine high-toughness, high-temperature oxidation-resistant materials and high-strength metal materials in different layers. The thickness ratio is made into multi-layer materials to obtain composite microlayer boards with the properties of two or more materials. This typical high-temperature intermetallic compound and other micro-layer plate composite materials have both the toughness of metal and the strength and chemical stability of ceramics, and can be used to replace high-temperature alloys such as high-temperature alloys as heat-resistant covers for aerospace vehicles. In recent years, the United States has made great progress in the research of two heat-resistant materials, the superalloy honeycomb composite structure and the soft alloy multi-wall structure. Body connection problem. Our country has also carried out a lot of research in related fields, so the development of new technologies for testing the mechanical properties of materials based on the temperature field has broad prospects.

At present, the relatively mature three-point bending test generally relies on large-scale bending testing machines to perform out-of-position testing on material specimens. During the bending loading process, the sample is loaded at a uniform rate according to the relevant standards, and the force signal and displacement are sent to the computer through the corresponding load displacement sensing unit to draw the load-deflection curve, combined with the material section properties to obtain the stress-deflection under load. strain curve. However, traditional bending testing machines are mostly aimed at large-scale test pieces at room temperature, and do not involve the study of the mechanical properties of samples in the micro-nano scale, nor do they consider the influence of the temperature field on material properties, and most of them belong to off-site tests. In situ observation to the corresponding microscopic imaging system. The current development of in-situ test devices mainly has the following characteristics: (1) In terms of the compatibility between the test device and the imaging system, due to the limited cavity space of scanning electron microscopes, transmission electron microscopes and atomic force microscopes, so far Most of the research is focused on the simple in-situ nano-tensile testing of extremely small structures such as nanotubes, nanowires, and thin-film materials based on the principles of micro/nano-electromechanical systems. In-depth research on in-situ micro/nano mechanical performance testing; (2) From the perspective of test accuracy, it mainly focuses on the research and development of the reliability and stability of the micro-drive system, the precise measurement method of the load displacement signal, and the processing and clamping of the sample , on the medium problem.

In view of the fact that my country's research on the mechanical properties of materials such as composite microlayer boards and thermal barrier coatings is still relatively backward. Therefore, it is of great significance to develop testing methods for the mechanical properties of materials in high temperature environments. By testing the mechanical properties of each component layer material in the microlayer board, it lays the foundation for the prediction of the performance of the microlayer board, the study of the deformation and failure mechanism. Based on this, on the basis of macroscopic tensile, bending and torsion and other material mechanical performance testing methods, combined with the concept of temperature field and in-situ testing, it has become a trend to develop traditional testing devices in the direction of miniaturization, precision and multifunctionality. a trend. The present invention just caters to the development requirements of the above material mechanical performance test, and develops a material in-situ three-point bending experimental device based on the temperature field.

Contents of the invention

The object of the present invention is to provide an in-situ three-point bending test platform for material mechanical properties with adjustable test environment temperature, which solves the above-mentioned problems in the prior art. The invention not only can meet the standard testing process of material mechanical properties, but also provides technical means for temperature field response of material mechanical properties in in-situ mechanical testing. It plays a pivotal role in advancing the performance in-situ testing technology of high-performance materials in high-temperature environments.

Above-mentioned purpose of the present invention is achieved through the following technical solutions:

In-situ three-point bending test platform for material mechanical properties with adjustable test environment temperature, including precision drive transmission unit, detection unit, imaging system unit, temperature field control unit, and auxiliary support unit, aiming at the microstructure of materials under different temperature fields In-situ real-time dynamic observation of appearance, lattice change, crack initiation and expansion, etc.;

The precision drive transmission unit is composed of a DC motor 3, a shaft 20, a worm 19 and a worm wheel 21, wherein the DC motor 3 is fastened on the frame 2 by screws II 18, the output shaft of the motor 3 is fixedly connected with the worm 19, and the worm wheel 21 decelerates and outputs the power to the shaft 20 to achieve a large deceleration and torque increase; the shaft 20 drives the gear II 33 to rotate, and the rotation motion is simultaneously transmitted to the gear I 35 through the meshing action of the gears, and the eccentric holes of the gears I, II 35, and 33 respectively pass through The pin shafts I, II36, 22 are connected with the connecting rods I, II37, 31; the other ends of the connecting rods I, II37, 31 are respectively connected with the sliders I, II23, 29 through the pin shafts III, IV32, 30; through this structure, the The rotary motion of the eccentric hole of the gear pair is converted into the linear motion of the sliders I, II23, 29; the sliders I, II23, 29 are guided by the slide rails I, II25, 28 respectively, and the V-shaped groove is used for guidance between them. Slide rails I, II 25, 28 are respectively fixed to the frame 2 by screws V27; the precision drive transmission unit is arranged in a completely symmetrical manner, and the rotary motion of gears I, II 35, 33 is cleverly converted into The linear motion of sliders Ⅰ, Ⅱ 23, 29, the output load is stable, reliable and symmetrically distributed;

The detection unit is composed of a force sensor 6, laser displacement sensors I, II 5, 8, wherein the two ends of the force sensor 6 are respectively fixedly connected with the indenter 7 and the frame 2 through connecting threads, and the laser displacement sensors I, II 5, 8 are connected with Frames 2 are fixedly connected by screws IV26; the force sensor 6, laser displacement sensors I, II5, and 8 respectively detect the change of load and displacement of the test piece 10 during the three-point bending deformation process;

The imaging system unit is mainly composed of a CCD industrial imaging lens 12, brackets I, II 15, 11, a swivel frame 14, a pressure plate 13 and 16 adjustment knobs, wherein the CCD industrial imaging lens 12 is fastened to the pressure plate 13 by screws VI34 It can rotate with the slewing frame 14; the brackets I, II 15, 11 and the frame 2 are fixed by screws Ⅲ 24 to support the CCD industrial imaging lens 12; the adjustment knob 16 can adjust the position of the CCD lens The imaging angle is adjusted; the imaging system unit utilizes the CCD imaging lens 12 to observe phenomena such as material microstructure morphology, lattice changes, crack initiation, and expansion;

Described temperature field control unit is mainly made up of heating resistance wire 9 and temperature controller 4, and wherein, temperature controller 4 is a voltage-adjustable switch, just can be convenient by controlling temperature controller 4 to the power supply voltage of heating resistance wire 9 The adjustment is to the heating temperature of test piece 10, to realize different heating temperatures;

The auxiliary support unit is mainly composed of a frame 2 and an upper cover 1, and the upper cover 1 and the frame 2 are fixedly connected by screws I17; the entire test platform is divided into two parts by the frame 2 and the upper cover 1. The relatively independent space can effectively avoid signal interference between the drive, control components and the detection unit, and protect the motor from the influence of the heating resistance wire.

The precision drive transmission unit subtly converts the rotational motion of the gears I, II 35, 33 into the linear motion of the sliders I, II 23, 29 through the classic crank-slider mechanism, and then pushes the test piece 10 to press the indenter 7, Deflection occurs; since the indenter 7 is fixed, the two ends of the test piece 10 move downward synchronously under the action of the sliders I, II 23, 29, which ensures that the height of the center point of the test piece 10 does not change, and is easy to realize In-situ observation; and the two crank-slider mechanisms are symmetrically arranged, leaving a large space in the central observation area of the test piece 10, which is convenient for applying a temperature field and an in-situ imaging lens.

The imaging system unit adopts a high-magnification solid-state CCD industrial imaging lens 12 and its adjustment mechanism, which can perform in-situ observations on the microstructure, lattice changes, crack initiation, and expansion of the material during the test; the rotation adjustment The knob 16 can adjust the field of view imaging angle of the CCD industrial imaging lens 12 to ensure a better imaging angle of view.

The temperature field control unit conducts contact heating on the test piece 10 through the heating resistance wire 9, and adjusts the power supply voltage to the heating resistance wire 9 through the temperature controller 5, and the test piece 10 will be at different temperatures under different power supply voltages. The heat balance can be reached, and then the variable temperature loading on the test piece 10 can be completed.

The frame 2 as a whole adopts a T-shaped structure, and the entire test platform is divided into two relatively independent spaces in combination with the upper cover plate 1, and the DC motor 3, the temperature controller 4, the force sensor 6, the laser displacement sensors I, II 5 , 8 are separated on both sides, avoiding the interference of the high current of the DC motor 3 and the temperature controller 4 on the force sensor 6, the small current of the laser displacement sensor I, II 5, and 8; it is also beneficial to the heating of the resistance wire 9 The heat is separated on the loading side to reduce the impact on the motor.

The two ends of the force sensor 6 are fixedly connected to the indenter 7 and the frame 2 respectively, and two laser displacement sensors I, II 5, and 8 are used to measure the downward displacement of the two ends of the test piece 10 respectively, and the two data are averaged, It can effectively reduce the problem of inaccurate winding test caused by the deflection of the test piece, and the test method can obtain better test results.

The beneficial effect of the present invention is that: the present invention is not limited to the traditional three-point bending mechanical performance test, and combines the original test means with the in-situ test technology, and can target materials under different temperature fields during the three-point bending process. In situ and real-time dynamic observation of microstructure morphology, lattice changes, crack initiation and expansion, etc. In terms of driving, a symmetrical gear arrangement is adopted to form a typical crank-slider mechanism to drive the bending indenters on both sides to realize the bending action. In this arrangement, the indenters on both sides are respectively driven by two sets of crank-slider mechanisms. A large space is reserved in the middle of the component to facilitate the application and control of the temperature field. In terms of overall structure, the test device has a compact structure, and the drive module, detection module and load temperature field module are distributed in different isolated spaces, which avoids mutual interference between signals between modules. In terms of applying the temperature field, the device adopts heating resistance wire contact heating, the structure is simple and convenient to control, and the temperature adjustment in a large range can be realized in combination with the principle of heat balance. The test device caters to the current development needs of material mechanical performance testing, and develops a material in-situ three-point bending mechanical testing platform based on the temperature field, which not only meets the standard material mechanical performance testing process, but also can It provides a technical means for the temperature field response of the mechanical properties of materials. At the same time, this test platform also has the advantages of simple and compact structure, stable transmission, combination of stress field and temperature field, etc., and has broad application prospects.

Description of drawings

The accompanying drawings described here are used to provide a further understanding of the present invention, and constitute a part of the application. The schematic examples and descriptions of the present invention are used to explain the present invention, and do not constitute improper limitations to the present invention.

Fig. 1 is the complete machine shaft side view of the present invention;

Fig. 2 is the left view of the present invention;

Fig. 3 is the front view of the present invention;

Fig. 4 is a partially enlarged (2:1) schematic diagram of the heating part of the test piece of the present invention.

In the figure: 1. Upper cover plate; 2. Rack; 3. DC motor; 4. Temperature controller; 5. Laser displacement sensor Ⅰ; 6. Force sensor; 7. Pressure head; 8. Laser displacement sensor Ⅱ; 9 .Heating resistance wire; 10. Specimen; 11. Bracket Ⅱ; 12. CCD industrial imaging lens; 13. Press plate; 14. Rotary frame; 15. Bracket Ⅰ; ;19. Worm; 20. Shaft; 21. Worm gear; 22. Pin II; 23. Slider I; 24. Screw III; 25. Slide rail I; 26. Screw IV; 27. Screw V; 28. Slide rail Ⅱ; 29. Slider Ⅱ; 30. Pin shaft Ⅳ; 31. Connecting rod Ⅱ; 32. Pin shaft Ⅲ; 33. Gear Ⅱ; 34. Screw Ⅵ; 35. Gear Ⅰ; 36 Pin shaft Ⅰ; 37. Connecting rod I.

Detailed ways

The detailed content of the present invention and its specific implementation will be further described below in conjunction with the accompanying drawings.

Referring to Figures 1 to 4, the in-situ three-point bending test platform for material mechanical properties with adjustable test environment temperature of the present invention includes a precision drive transmission unit, a detection unit, an imaging system unit, a temperature field control unit, and an auxiliary support unit , in-situ real-time dynamic observation of the microstructure morphology, lattice changes, crack initiation and expansion of materials under different temperature fields;

The precision drive transmission unit is composed of a DC motor 3, a shaft 20, a worm 19 and a worm wheel 21, wherein the DC motor 3 is fastened on the frame 2 by screws II 18, the output shaft of the motor 3 is fixedly connected with the worm 19, and the worm wheel 21 decelerates and outputs the power to the shaft 20 to achieve a large deceleration and torque increase; the shaft 20 drives the gear II 33 to rotate, and the rotation motion is simultaneously transmitted to the gear I 35 through the meshing action of the gears, and the eccentric holes of the gears I, II 35, and 33 respectively pass through The pin shafts I, II36, 22 are connected with the connecting rods I, II37, 31; the other ends of the connecting rods I, II37, 31 are respectively connected with the sliders I, II23, 29 through the pin shafts III, IV32, 30; through this structure, the The rotary motion of the eccentric hole of the gear pair is converted into the linear motion of the sliders I, II23, 29; the sliders I, II23, 29 are guided by the slide rails I, II25, 28 respectively, and the V-shaped groove is used for guidance between them. Slide rails I, II 25, 28 are respectively fixed to the frame 2 by screws V27; the precision drive transmission unit is arranged in a completely symmetrical manner, and the rotary motion of gears I, II 35, 33 is cleverly converted into The linear motion of sliders Ⅰ, Ⅱ 23, 29, the output load is stable, reliable and symmetrically distributed;

The detection unit is composed of a force sensor 6, laser displacement sensors I, II 5, 8, wherein the two ends of the force sensor 6 are respectively fixedly connected with the indenter 7 and the frame 2 through connecting threads, and the laser displacement sensors I, II 5, 8 are connected with Frames 2 are fixedly connected by screws IV26; the force sensor 6, laser displacement sensors I, II5, and 8 respectively detect the change of load and displacement of the test piece 10 during the three-point bending deformation process;

The imaging system unit is mainly composed of a CCD industrial imaging lens 12, brackets I, II 15, 11, a swivel frame 14, a pressure plate 13 and 16 adjustment knobs, wherein the CCD industrial imaging lens 12 is fastened to the pressure plate 13 by screws VI34 It can rotate with the slewing frame 14; the brackets I, II 15, 11 and the frame 2 are fixed by screws Ⅲ 24 to support the CCD industrial imaging lens 12; the adjustment knob 16 can adjust the position of the CCD lens The imaging angle is adjusted; the imaging system unit utilizes the CCD imaging lens 12 to observe phenomena such as material microstructure morphology, lattice changes, crack initiation, and expansion;

Described temperature field control unit is mainly made up of heating resistance wire 9 and temperature controller 4, and wherein, temperature controller 4 is a voltage-adjustable switch, just can be convenient by controlling temperature controller 4 to the power supply voltage of heating resistance wire 9 The adjustment is to the heating temperature of test piece 10, to realize different heating temperatures;

The auxiliary support unit is mainly composed of a frame 2 and an upper cover 1, and the upper cover 1 and the frame 2 are fixedly connected by screws I17; the entire test platform is divided into two parts by the frame 2 and the upper cover 1. The relatively independent space can effectively avoid signal interference between the drive, control components and the detection unit, and protect the motor from the influence of the heating resistance wire.

The precision drive transmission unit subtly converts the rotational motion of the gears I, II 35, 33 into the linear motion of the sliders I, II 23, 29 through the classic crank-slider mechanism, and then pushes the test piece 10 to press the indenter 7, Deflection occurs; since the indenter 7 is fixed, the two ends of the test piece 10 move downward synchronously under the action of the sliders I, II 23, 29, which ensures that the height of the center point of the test piece 10 does not change, and is easy to realize In-situ observation; and the two crank-slider mechanisms are symmetrically arranged, leaving a large space in the central observation area of the test piece 10, which is convenient for applying a temperature field and an in-situ imaging lens.

The imaging system unit adopts a high-magnification solid-state CCD industrial imaging lens 12 and its adjustment mechanism, which can perform in-situ observations on the microstructure, lattice changes, crack initiation, and expansion of the material during the test; the rotation adjustment The knob 16 can adjust the field of view imaging angle of the CCD industrial imaging lens 12 to ensure a better imaging angle of view.

The temperature field control unit conducts contact heating on the test piece 10 through the heating resistance wire 9, and adjusts the power supply voltage to the heating resistance wire 9 through the temperature controller 5, and the test piece 10 will be at different temperatures under different power supply voltages. The heat balance can be reached, and then the variable temperature loading on the test piece 10 can be completed.

The frame 2 as a whole adopts a T-shaped structure, and the entire test platform is divided into two relatively independent spaces in combination with the upper cover plate 1, and the DC motor 3, the temperature controller 4, the force sensor 6, the laser displacement sensors I, II 5 , 8 are separated on both sides, avoiding the interference of the high current of the DC motor 3 and the temperature controller 4 on the force sensor 6, the small current of the laser displacement sensor I, II 5, and 8; it is also beneficial to the heating of the resistance wire 9 The heat is separated on the loading side to reduce the impact on the motor.

The two ends of the force sensor 6 are fixedly connected to the indenter 7 and the frame 2 respectively, and two laser displacement sensors I, II 5, and 8 are used to measure the downward displacement of the two ends of the test piece 10 respectively, and the two data are averaged, It can effectively reduce the problem of inaccurate winding test caused by the deflection of the test piece, and the test method can obtain better test results.

The precision drive transmission unit is powered by a DC servo motor, which is decelerated and torque-increased through the deceleration of a precision worm gear with a large reduction ratio. The output power of the worm shaft adopts a typical crank-slider mechanism, which converts the rotational motion of the gear into the linear motion of the slider through the eccentric output hole, and then compresses the specimen to undergo deflection deformation. During the deformation process, the simultaneous pressing down of the indenters on both sides can ensure that the maximum deflection in the middle of the specimen does not move, and it is easy to realize in-situ observation. The detection unit includes a force sensor and a laser displacement sensor, which respectively detect the changes of the load and displacement of the test piece during the bending deformation process. The imaging system unit is composed of a CCD lens, a lens rotation adjustment mechanism and a bracket, which can observe the microstructure morphology, lattice change, crack initiation and expansion of the material in real time. The temperature field control unit is composed of a heating resistance wire and a temperature control switch. By adjusting the power supply voltage of the temperature control switch, different test temperatures can be provided for the test specimen.

Referring to shown in Fig. 1 to Fig. 4, concrete work process of the present invention is as follows:

Application of the temperature field and adjustment of the in-situ imaging system: before the experiment starts, turn on the temperature field control switch, and adjust the current in the heating resistance wire 9 by means of voltage control. When the heat lost to the surrounding environment reaches a dynamic balance, keep the heating voltage constant until the entire test process is completed. Loosen the screw Ⅵ34 of the pressure plate 13 before the experiment, adjust the distance between the lens and the specimen to obtain a clear image, during the test, under the support of the indenter 7, the center point of the specimen remains unchanged, adjust the adjustment knob 16 can realize the adjustment of small angle to get the best image effect.

The realization of three-point bending: firstly, the power is transmitted from the DC motor 3, which drives the worm 19 and the worm wheel 21 to achieve a large deceleration and torque increase. Secondly, the worm wheel 21 transmits the power to the gear I35, and at this time, the gear II33 meshing with the gear I35 rotates in the opposite direction. The rotational motion of the gears I, II35, 33 is transmitted to the sliders I, II23, 29 through the connecting rods I, II37, 31, and the sliders I, II23, 29 move linearly under the guidance of the slide rails I, II25, 28, The whole mechanism constitutes a pair of crank-slider mechanisms, which finally convert the rotational motion of the gears I, II 35, 33 into the linear motion of the sliders I, II 23, 29, and then push the test piece 10 to press the indenter 7, so that the test piece 10 generates Three-point bending deflection. During the test, the force sensor 6 and the laser displacement sensors Ⅰ, Ⅱ 5, and 8 amplify and sample the collected signals and send them to the processing computer to obtain various mechanical performance parameters of the material. At the same time, the CCD industrial imaging lens 12 collects The obtained microscopic deformation image information of the specimen is stored, and corresponding to the stress-strain curve of the specimen in real time, the in-situ mechanical test parameters of the material based on the pre-heating temperature field can be easily obtained.

The above descriptions are only preferred examples of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made to the present invention shall be included within the protection scope of the present invention.

Claims (6)

1. material mechanical performance original position three-point bending test platform that the test environment temperature is adjustable, it is characterized in that: comprise accurate gear unit, detecting unit, imaging system unit, Temperature Field Control unit, the supplemental support unit of driving, carry out in real time dynamic observation of original position for germinating, the expansion of material microstructure morphology, lattice variations, crackle under the different temperatures field action;

The described accurate gear unit that drives is comprised of direct current generator (3), axle (20), worm screw (19) and worm gear (21), wherein, direct current generator (3) is fastened on the frame (2) by screw II (18), the output shaft of motor (3) and worm screw (19) are connected, and slowing down through worm gear (21) outputs power on the axle (20); Axle (20) driven gear II (33) is rotated, engagement by gear will rotatablely move and pass to simultaneously gear I (35), and the eccentric orfice of gear I, II (35,33) links to each other with connecting rod I, II (37,31) by bearing pin I, II (36,22) respectively; The other end of connecting rod I, II (37,31) links to each other with slide block I, II (23,29) by bearing pin III, IV (32,30) respectively; Rotatablely moving of gear pair eccentric orfice is converted into the rectilinear motion of slide block I, II (23,29) by this structure; Slide block I, II (23,29) are led by slide rail I, II (25,28) respectively, adopt the V-type groove to lead between the two, and slide rail I, II (25,28) are fixed by screw V (27) respectively and between the frame (2); The described accurate gear unit that drives adopts the full symmetric mode to arrange, utilize slider-crank mechanism dexterously rotatablely moving of gear I, II (35,33) to be converted into the rectilinear motion of slide block I, II (23,29), output loads is stable, reliable and symmetrical;

Described detecting unit is made of power sensor (6), laser displacement sensor I, II (5,8), wherein, power sensor (6) two ends are fixedly connected with pressure head (7), frame (2) respectively by connecting thread, are fixedly connected with by screw IV (26) between laser displacement sensor I, II (5,8) and the frame (2); Described power sensor (6), laser displacement sensor I, II (5,8) detect respectively the variation of test specimen (10) load and displacement in the three-point bending deformation process;

Described imaging system unit mainly is made of CCD industry imaging lens (12), support I, II (15,11), reversing frame (14), pressing plate (13) and adjusting knob (16) part, wherein, CCD industry imaging lens (12) is fastened on it between pressing plate (13) and the reversing frame (14) by screw VI (34), can rotate with reversing frame (14); Fixing by screw III (24) between support I, II (15,11) and the frame (2), be used for supporting CCD industry imaging lens (12); Can regulate the imaging angle of CCD camera lens by adjusting knob (16); Described imaging system unit by using CCD imaging lens (12) can be observed germinating, the expansion of Fine Texture of Material pattern, lattice variations, crackle;

Described Temperature Field Control unit mainly is comprised of resistive heater (9) and temperature controller (4), wherein, temperature controller (4) is a switch that voltage is adjustable, just can regulate easily heating-up temperature to test specimen (10) for the supply voltage of resistive heater (9) by control temperature controller (4), to realize different heating-up temperatures;

Described supplemental support unit mainly is made of frame (2), upper cover plate (1), is fixedly connected with by screw I (17) between upper cover plate (1) and the frame (2); By frame (2) and upper cover plate (1) whole test platform is divided into two relatively independent spaces, avoids driving, the signal between control assembly and the detecting unit disturbs, the protection motor is not subjected to the impact of resistive heater.

2. the adjustable material mechanical performance original position three-point bending test platform of test environment temperature according to claim 1, it is characterized in that: the described accurate rectilinear motion that gear unit is converted into rotatablely moving of gear I, II (35,33) by slider-crank mechanism slide block I, II (23,29) that drives, and then promotion test specimen (10) is pressed to pressure head (7), the generation deflection deformation; Because pressure head (7) maintains static, test specimen (10) two ends move down under the effect of slide block I, II (23,29) synchronously, have guaranteed that the height of the central point of test specimen (10) does not change, and are convenient to realize home position observation; And two slider-crank mechanisms taking are arranged symmetrically with, and leave larger space in test specimen (10) observation area, center, are convenient to apply temperature field and in situ imaging camera lens.

3. the adjustable material mechanical performance original position three-point bending test platform of test environment temperature according to claim 1, it is characterized in that: described imaging system unit adopts the solid-state CCD industry imaging lens (12) of high multiple and adjusting mechanism thereof, can germinating, the expansion to Fine Texture of Material pattern, lattice variations, crackle carry out in-situ observation in test process; Rotate adjusting knob (16) and can regulate the view field imaging angle of CCD industry imaging lens (12), guarantee to have preferably imaging visual angle.

4. the adjustable material mechanical performance original position three-point bending test platform of test environment temperature according to claim 1, it is characterized in that: described Temperature Field Control unit carries out contact heating by resistive heater (9) to test specimen (10), by the supply voltage of temperature controller (5) adjusting to resistive heater (9), test specimen (10) can reach thermal equilibrium under the different supply voltages under different temperature, and then the alternating temperature of finishing test specimen (10) loads.

5. the adjustable material mechanical performance original position three-point bending test platform of test environment temperature according to claim 1, it is characterized in that: the T-shaped structure of the whole employing of described frame (2), in conjunction with upper cover plate (1) whole test platform is divided into two relatively independent spaces, with direct current generator (3), temperature controller (4) and power sensor (6), the laser displacement sensor I, II (5,8) separate in both sides, avoided the large electric current of direct current generator (3) and temperature controller (4) to power sensor (6), the laser displacement sensor I, II (5, the interference of Weak current 8); Also help simultaneously the heat of resistive heater (9) is separated loading a side, reduce the impact on motor.

6. the adjustable material mechanical performance original position three-point bending test platform of test environment temperature according to claim 1, it is characterized in that: described power sensor (6) two ends are fixedly connected with pressure head (7), frame (2) respectively, adopt two laser displacement sensor I, II (5,8) measure respectively test specimen (10) two ends to bottom offset, two paths of data is averaged.

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