Transmission electron microscope in-situ biaxial plane stress mechanical experiment platform

Abstract

The utility model relates to mechanics research equipment technical field especially relates to a kind of transmission electron microscope in situ biaxial plane stress mechanics experimental platform, it includes: drive base, horizontal drive rod, vertical drive rod and multiple hot drive beams.Horizontal drive rod is located on the horizontal direction of sample, and is connected with sample;Vertical drive rod is located on the vertical direction of sample, and is connected with sample;Multiple hot drive beams are located on drive base, and are connected with horizontal drive rod, vertical drive rod respectively, drive horizontal drive rod to move horizontally, drive vertical drive rod to move vertically.The utility model provides a kind of transmission electron microscope in situ biaxial plane stress mechanics experimental platform, adopts the space optimization design of cross layout, reduces multi-axis load crosstalk by physical isolation mechanics path;Adopt biaxial plane stress loading, can independently or cooperatively exert in-plane stress such as tension in vertical direction and horizontal direction to sample.

Description

Technical Field

[0001] This utility model relates to the field of mechanical research equipment technology, and in particular to an in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy. Background Technology

[0002] The mechanical properties of materials (such as impact resistance, fatigue performance, and plastic machinability) are key factors determining the engineering application value of structural materials. Developing novel high-performance materials requires in-depth understanding of the deformation mechanisms at the nanoscale, atomic, and even sub-angstrom scales. Transmission electron microscopy (TEM), with its high spatial resolution (up to 0.1 nm), has become a core tool for characterizing microstructures. However, traditional non-in-situ research methods require independent observation of samples at different deformation stages, which inevitably leads to the following problems: observation area shift, inconsistent partitioning due to multiple sampling, and inability to track the dynamic evolution of the same micro-region; distortion of the deformation mechanism, as microstructural relaxation after material unloading may mask the true deformation mechanism, leading to biased mechanism inferences. To overcome these limitations, researchers have developed an in-situ mechanical experimental platform for TEM. By integrating mechanical loading devices, with mainstream driving methods including electrostatic drive, shape memory alloy drive, piezoelectric drive, fluid drive, electromagnetic drive, and thermal drive, in-situ mechanical experiments and real-time observation of the same sample region can be achieved.

[0003] Current mainstream TEM in-situ mechanical platforms generally employ a uniaxial loading design: uniaxial tension / compression is achieved through a cantilever beam structure of a Micro-Electro-Mechanical Systems (MEMS) chip, or nanoindentation is performed using a first piezoelectric ceramic-driven probe. While such systems can provide sub-nanometer displacement resolution, they are limited by the confined space and mechanical degrees of freedom of the TEM sample cavity, making it impossible to simultaneously apply controllable loads in orthogonal directions, leading to the following key drawbacks: 1. Unable to simulate real multiaxial stress environment: Materials often bear biaxial plane stress in actual working conditions (such as thermal expansion mismatch of semiconductor devices, biaxial strain in the plane of two-dimensional materials), while uniaxial loading can only induce deformation in a single direction, which is difficult to reflect the microscopic mechanism under complex stress conditions. 2. Loading direction cannot be switched: The loading direction of existing MEMS chips is fixed by the prefabricated structure, and the axis of force application cannot be dynamically adjusted during the experiment. Utility Model Content

[0004] This invention provides an in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy, which solves the defect of traditional uniaxial loading systems in the prior art that cannot simulate real multiaxial stress environments.

[0005] This invention provides an in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy, comprising: Driven substrate; A horizontal drive rod is located in the horizontal direction of the sample and is connected to the sample. A vertical drive rod is located in the vertical direction of the sample and is connected to the sample; Multiple thermally driven beams are disposed on the driving base and connected to the horizontal driving rod and the vertical driving rod respectively. The thermally driven beams drive the horizontal driving rod to move horizontally and drive the vertical driving rod to move vertically based on the principle of thermal expansion.

[0006] According to the in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy provided by this utility model, multiple thermal drive beams are symmetrically arranged on both sides of each of the horizontal drive rods, and the thermal drive beams are inclinedly arranged between the drive base and the horizontal drive rod; multiple thermal drive beams are symmetrically arranged on both sides of each of the vertical drive rods, and the thermal drive beams are inclinedly arranged between the drive base and the vertical drive rod.

[0007] According to the in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy provided by this utility model, multiple thermally driven beams located on both sides of the same horizontal driving rod form a "V" shaped beam structure; multiple thermally driven beams located on both sides of the same vertical driving rod form a "V" shaped beam structure.

[0008] According to the transmission electron microscope in-situ biaxial plane stress mechanics experimental platform provided by this utility model, the horizontal drive rods are all located at the top or bottom of the drive base, and each has a first connecting block extending vertically at the end near the sample. The horizontal drive rods are connected to the sample through the first connecting block.

[0009] According to the in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy provided by this utility model, the vertical drive rods are all located at the top or bottom of the drive base, and each has a second connecting block extending vertically at the end near the sample. The vertical drive rods are connected to the sample through the second connecting block.

[0010] The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy provided by this utility model further includes: a mass block disposed on the driving substrate.

[0011] The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy provided by this utility model further includes: a sample platform located at the intersection of the extension direction of the horizontal drive rod and the extension direction of the vertical drive rod.

[0012] According to the in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy provided by this utility model, the thermally driven beam is provided with an electrical interface for connecting to a power source and for performing expansion and contraction movements based on the principle of thermal expansion.

[0013] According to the in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy provided by this utility model, the vertical drive rods are respectively located at the upper and lower ends of the sample.

[0014] According to the in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy provided by this utility model, the horizontal drive rods are respectively located at the left and right ends of the sample.

[0015] This invention provides an in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy, comprising: a driving base, a horizontal driving rod, a vertical driving rod, and multiple thermally driven beams. The horizontal driving rod is located in the horizontal direction of the sample and connected to the sample; the vertical driving rod is located in the vertical direction of the sample and connected to the sample; multiple thermally driven beams are disposed on the driving base and connected to the horizontal and vertical driving rods respectively. The thermally driven beams, based on the principle of thermal expansion, drive the horizontal driving rod to move horizontally and the vertical driving rod to move vertically. In this in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy, the driving base serves as the supporting structure for the thermally driven beams. The thermally driven beams drive the horizontal driving rod to move horizontally and the vertical driving rod to move vertically, thereby applying horizontal and vertical stresses to the sample. This invention employs a cross-shaped spatial optimization design, reducing multiaxial load crosstalk by physically isolating mechanical paths; and uses biaxial plane stress loading, which can independently or collaboratively apply in-plane stresses such as tension in the vertical and horizontal directions to the sample. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a front structural schematic diagram of the in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy provided by this utility model.

[0018] Figure 2 This is a schematic diagram of the back structure of the in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy provided by this utility model.

[0019] Figure label: 1: Drive base; 2: Horizontal drive rod; 3: Vertical drive rod; 4: Thermal drive beam; 5: First connecting block; 6: Mass block. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0021] In the description of this embodiment, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this embodiment and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this embodiment.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this embodiment, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0023] In this embodiment, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," "link," and "fix" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this embodiment based on the specific circumstances.

[0024] In this embodiment of the utility model, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0025] Analysis of existing technologies reveals the following pressing technical problems with current transmission electron microscopy (TEM) in-situ mechanical experimental platforms: 1. Lack of multiaxial stress simulation capability: Traditional uniaxial loading designs (such as MEMS cantilever beams or piezoelectric probes) cannot apply controllable loads in orthogonal directions simultaneously, which makes it impossible to observe the micro-deformation behavior of materials under biaxial plane stress (such as crack propagation path selection and dislocation slip system activation) in situ, which seriously restricts the mechanistic analysis of the material's real service performance (such as impact resistance and fatigue life).

[0026] 2. Rigid fixation of loading direction: Existing systems rely on prefabricated structures to fix the loading direction, and the axial direction of the force cannot be dynamically adjusted during the experiment, making it difficult to meet the research needs of multi-directional stress paths under complex working conditions.

[0027] Dual-axis loading implementation has the following bottlenecks: 1. Spatial conflict: The internal space of the TEM sample holder is insufficient, and the existing mechanical design is difficult to accommodate orthogonally arranged independent drive mechanisms (such as horizontal and vertical actuators). 2. Load crosstalk and the lack of physical decoupling mechanism in the multi-directional force transmission path lead to inaccurate positioning of stress measurement errors in each axis. 3. Biaxial loading causes sample drift, which disrupts the stability of electron beam focusing and renders atomic-scale dynamic observations ineffective.

[0028] The aforementioned shortcomings collectively render traditional platforms unable to meet the needs of studying the microscopic mechanisms of advanced structural materials (such as high-entropy alloys and nanolayered composite materials) under synergistic multiaxial stress. Therefore, developing an in-situ mechanical experimental platform capable of simultaneously applying independent and controllable biaxial plane stresses while being compatible with the spatial constraints of TEM chambers has become an urgent need for technological upgrading in this field.

[0029] The following is combined Figure 1 and Figure 2 This invention describes an in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy. The platform comprises: a driving base 1, a horizontal driving rod 2, a vertical driving rod 3, and multiple thermally driven beams 4.

[0030] The horizontal drive rod 2 is located in the horizontal direction of the sample and is connected to the sample; the vertical drive rod 3 is located in the vertical direction of the sample and is connected to the sample; multiple thermal drive beams 4 are set on the drive base 1 and are connected to the horizontal drive rod 2 and the vertical drive rod 3 respectively. The thermal drive beams 4 drive the horizontal drive rod 2 to move horizontally and drive the vertical drive rod 3 to move vertically based on the principle of thermal expansion.

[0031] Specifically, the driving base 1 serves as the support device in the entire device, and the fixed end of the thermal driving beam 4 is fixed on the driving base 1, thereby realizing the expansion and contraction of the movable end of the thermal driving beam 4 based on the principle of thermal expansion, which in turn drives the horizontal driving rod 2 to move horizontally and the vertical driving rod 3 to move vertically.

[0032] It should be understood that the horizontal drive rod 2 and the vertical drive rod 3 are equipped with independent power sources, that is, the horizontal drive rod 2 and the vertical drive rod 3 are equipped with independent thermal drive beams 4 for independent driving, and the horizontal drive rod 2 and the vertical drive rod 3 do not interfere with each other's movement.

[0033] The horizontal drive rods 2 are located on the left and right sides of the sample and are used to drive the sample to move horizontally. Multiple horizontal drive rods 2 constitute a horizontal actuator. The vertical drive rods 3 are located at the top and bottom ends of the sample and are used to drive the sample to move vertically. Multiple vertical drive rods 3 constitute a vertical actuator. The space optimization design with a cross-shaped layout reduces multiaxial load crosstalk by physically isolating the mechanical path. The biaxial plane stress loading can independently or collaboratively apply in-plane stresses such as tension in the vertical and horizontal directions to the sample.

[0034] This invention provides an in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy, comprising: a driving base 1, a horizontal driving rod 2, a vertical driving rod 3, and multiple thermally driven beams 4. The horizontal driving rod 2 is located in the horizontal direction of the sample and connected to the sample; the vertical driving rod 3 is located in the vertical direction of the sample and connected to the sample; the multiple thermally driven beams 4 are disposed on the driving base 1 and connected to the horizontal driving rod 2 and the vertical driving rod 3 respectively. Based on the principle of thermal expansion, the thermally driven beams 4 drive the horizontal driving rod 2 to move horizontally and the vertical driving rod 3 to move vertically. In this in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy, the driving base 1 serves as the supporting structure for the thermally driven beams 4. The thermally driven beams 4 drive the horizontal driving rod 2 to move horizontally and the vertical driving rod 3 to move vertically, thereby applying horizontal and vertical stresses to the sample. This invention adopts a cross-shaped spatial optimization design, reducing multiaxial load crosstalk by physically isolating the mechanical path; and employs biaxial plane stress loading, which can independently or collaboratively apply in-plane stresses such as tension in the vertical and horizontal directions to the sample.

[0035] In one embodiment of this utility model, multiple thermal drive beams 4 are symmetrically arranged on both sides of each horizontal drive rod 2, and the thermal drive beams 4 are inclinedly arranged between the drive base 1 and the horizontal drive rod 2; multiple thermal drive beams 4 are symmetrically arranged on both sides of each vertical drive rod 3, and the thermal drive beams 4 are inclinedly arranged between the drive base 1 and the vertical drive rod 3. In this embodiment, by arranging multiple thermal drive beams 4 on both sides of the horizontal drive rod 2 and the vertical drive rod 3, the driving of the horizontal drive rod 2 and the vertical drive rod 3 is precise. Specifically, multiple thermal drive beams 4 are arranged on the upper and lower sides of the horizontal drive rod 2, and the synchronous extension and retraction of the thermal drive beams 4 on the upper and lower sides ensures that the horizontal drive rod 2 does not shift vertically when moving horizontally; similarly, multiple thermal drive beams 4 are arranged on the left and right sides of the vertical drive rod 3, and the synchronous extension and retraction of the thermal drive beams 4 on the left and right sides ensures that the vertical drive rod 3 does not shift horizontally when moving vertically.

[0036] In one embodiment of this utility model, multiple thermally driven beams 4 located on both sides of the same horizontal drive rod 2 form a "V" shaped beam structure; multiple thermally driven beams 4 located on both sides of the same vertical drive rod 3 also form a "V" shaped beam structure. Figure 1 In the structure shown, multiple thermally driven beams 4 located on both sides of the horizontal drive rod 2 and the vertical drive rod 3 form a symmetrical "V"-shaped beam structure. That is, the thermally driven beams 4 are inclined and symmetrically arranged between the drive base 1 and the drive rod. Preferably, to ensure that the left horizontal drive rod 2 moves to the left after thermal expansion, the right horizontal drive rod 2 moves to the right after thermal expansion, the upper vertical drive rod 3 moves upward after thermal expansion, and the lower vertical drive rod 3 moves downward after thermal expansion, the protruding direction of each "V"-shaped beam structure is away from the direction of the sample.

[0037] In one embodiment of this utility model, the horizontal drive rods 2 are all located at the top or bottom of the drive base 1, and each has a first connecting block 5 extending vertically at the end near the sample. The horizontal drive rods 2 are connected to the sample through the first connecting block 5. Alternatively, the vertical drive rods 3 are all located at the top or bottom of the drive base 1, and each has a second connecting block extending vertically at the end near the sample. The vertical drive rods 3 are connected to the sample through the second connecting block. This embodiment provides two arrangement methods for the horizontal drive rods 2 and the vertical drive rods 3, that is, they are staggered in the height direction to ensure that the movement of the horizontal drive rods 2 and the vertical drive rods 3 is independent of each other and does not interfere with each other. Specifically, when the horizontal drive rods 2 are staggered at the top or bottom, a first connecting block 5 extending vertically is provided at the end near the sample, thereby avoiding the vertical drive rods 3 and used for connecting to the sample; when the vertical drive rods 3 are staggered at the top or bottom, a second connecting block is also provided, thereby avoiding the horizontal drive rods 2 and used for connecting to the sample.

[0038] In one embodiment of this invention, the in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy further includes a mass block 6, which is disposed on the driving base 1. Specifically, the mass block 6 is disposed at the bottom of the driving base 1, increasing the local mass near the driving rod structure and enhancing stability. In the dual-actuator, the inertial stabilization effect is achieved by increasing the local mass to suppress high-frequency vibrations.

[0039] In one embodiment of this invention, the in-situ biaxial planar stress mechanics experimental platform for transmission electron microscopy further includes a sample platform located at the intersection of the extension directions of the horizontal drive rod 2 and the vertical drive rod 3. Specifically, the horizontal drive rod 2 and the vertical drive rod 3 form a biaxial "+" shaped structure, and a sample platform for mounting the sample is set in the center of the biaxial "+" shaped structure.

[0040] In one embodiment of this utility model, the thermally driven beam 4 is provided with an electrical interface for connection to a power source, and performs telescoping motion based on the principle of thermal expansion. In this embodiment, a power source is inserted through the electrical interface, and the Joule heat converted by the power source is transferred to the thermally driven beam 4, thereby causing the thermally driven beam 4 to elongate. It can be understood that the thermally driven beam 4 refers to a beam structure in which the material expands or contracts due to temperature changes (such as heating or cooling), thereby generating deformation or stress. In this embodiment, the thermally driven beam 4 is heated to cause it to expand and elongate, thereby driving the drive rod to move in a specific direction.

[0041] In one embodiment of this invention, vertical drive rods 3 are respectively disposed at the upper and lower ends of the sample; horizontal drive rods 2 are respectively disposed at the left and right ends of the sample. In this embodiment, a vertical drive rod 3 is arranged at the upper and lower ends of the sample, and a horizontal drive rod 2 is respectively disposed at the left and right ends of the sample, thereby realizing a cross-shaped biaxial stress experimental platform.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A transmission electron microscope in-situ biaxial plane stress mechanics experimental platform, characterized in that, include: Driving substrate (1); A horizontal drive rod (2) is located in the horizontal direction of the sample and is connected to the sample; The vertical drive rod (3) is located in the vertical direction of the sample and is connected to the sample; Multiple thermally driven beams (4) are disposed on the driving base (1) and connected to the horizontal driving rod (2) and the vertical driving rod (3) respectively. The thermally driven beams (4) drive the horizontal driving rod (2) to move horizontally and drive the vertical driving rod (3) to move vertically based on the principle of thermal expansion.

2. The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy according to claim 1, characterized in that, Multiple thermal drive beams (4) are symmetrically arranged on both sides of each horizontal drive rod (2), and the thermal drive beams (4) are inclined between the drive base (1) and the horizontal drive rod (2); multiple thermal drive beams (4) are symmetrically arranged on both sides of each vertical drive rod (3), and the thermal drive beams (4) are inclined between the drive base (1) and the vertical drive rod (3).

3. The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy according to claim 2, characterized in that, Multiple thermal drive beams (4) located on both sides of the same horizontal drive rod (2) form a "V" shaped beam structure; multiple thermal drive beams (4) located on both sides of the same vertical drive rod (3) form a "V" shaped beam structure.

4. The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy according to claim 1, characterized in that, The horizontal drive rods (2) are all located at the top or bottom of the drive base (1), and each has a first connecting block (5) extending vertically at the end near the sample. The horizontal drive rods (2) are connected to the sample through the first connecting block (5).

5. The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy according to claim 1, characterized in that, The vertical drive rods (3) are all located at the top or bottom of the drive base (1), and each has a second connecting block extending vertically at the end near the sample. The vertical drive rods (3) are connected to the sample through the second connecting block.

6. The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy according to claim 1, characterized in that, Also includes: Mass block (6) is disposed on the driving base (1).

7. The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy according to claim 1, characterized in that, Also includes: The sample platform is located at the intersection of the extension direction of the horizontal drive rod (2) and the extension direction of the vertical drive rod (3).

8. The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy according to claim 1, characterized in that, The thermally driven beam (4) is equipped with an electrical interface for connecting to a power source and for performing expansion and contraction movements based on the principle of thermal expansion.

9. The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy according to any one of claims 1 to 8, characterized in that, The vertical drive rod (3) is located at the upper and lower ends of the sample, respectively.

10. The in-situ biaxial plane stress mechanics experimental platform for transmission electron microscopy according to any one of claims 1 to 8, characterized in that, The horizontal drive rod (2) is located at the left and right ends of the sample, respectively.

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