A device and method for in-situ bending of a transmission electron microscope
By designing a blocking component and a cantilever structure on the sample rod of a transmission electron microscope (TEM), and utilizing the dual tilting function of the TEM, a low-cost in-situ bending experiment was achieved. This solved the problems of high cost and poor applicability of existing devices, and improved the versatility and accuracy of the experiment.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- HEFEI INSTITUTE OF PHYSICAL SCIENCE CHINESE ACADEMY OF SCIENCES
- Filing Date
- 2023-06-30
- Publication Date
- 2026-06-12
AI Technical Summary
Existing in-situ mechanical loading devices for transmission electron microscopy are complex in structure, expensive, and have high requirements for sample shape and size, making them difficult to promote and apply, especially in high-value precision instruments such as focused ion beam electron microscopes.
Design an in-situ bending device for transmission electron microscopy, including a sample cell and a blocking assembly. Utilize the double tilting function of the transmission electron microscope sample rod, and design a cantilever structure on the sample through the blocking assembly to achieve controllable deformation of the sample. Combine the lever principle to conduct in-situ bending experiments.
It reduces research costs, improves the versatility and applicability of experiments, is applicable to different types of transmission electron microscopes, simplifies sample preparation procedures, and enhances the success rate and accuracy of in-situ experiments.
Smart Images
Figure CN117030490B_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of material structure analysis technology, and particularly relates to an apparatus and method for in-situ bending in transmission electron microscopy. Background Technology
[0002] The relationship between the deformation and fracture processes of metals and the mechanisms of microstructural transformation has long been a focus of academic and industrial attention. In practical engineering applications, cases of metal deformation failure due to uniaxial tension are relatively rare; many metal failures are caused by complex stress states, such as bending. Therefore, studying the mechanisms of metal bending fracture processes, especially the response of metal microstructures to applied loads during bending, is extremely important. To further analyze the evolution of the microstructure in the initial bending state of metals from a mechanistic perspective, researchers have leveraged the nanoscale resolution advantage of transmission electron microscopy (TEM) to construct an in-situ research method for real-time observation and analysis of the microstructure of bent samples from the micrometer to the nanometer scale using TEM.
[0003] Existing in-situ mechanical loading devices for transmission electron microscopy (TEM) require the manufacture of sample rods tailored to specific TEM models. These custom-designed sample rods are equipped with mechanical loading modules, enabling in-situ observation of the mechanical loading process. However, these devices are complex and expensive, and have strict requirements on sample shape and dimensions. For some special samples, high-value precision instruments such as focused ion beam microscopes are needed for sample preparation, hindering the widespread adoption of these devices and in-situ experimental techniques. Therefore, there is an urgent need for a device and method for in-situ bending in TEM to address these issues. Summary of the Invention
[0004] To overcome the shortcomings of the prior art, this invention provides an apparatus and method for in-situ bending testing using transmission electron microscopy. This invention enables in-situ bending testing at low cost and facilitates the promotion of related technologies and research.
[0005] To achieve one of the above objectives, the present invention adopts the following technical solution:
[0006] A device for in-situ bending of a transmission electron microscope includes a sample that can be fixed in a sample cell of a transmission electron microscope sample rod, and a blocking component for preventing the sample from tilting with the sample cell and causing deformation of the sample. The blocking component includes a clamping part and a blocking part, the clamping part being connected to the transmission electron microscope sample rod, and the blocking part abutting against the bent end of the sample.
[0007] Preferably, the sample is in the shape of a semi-circular piece, with the semi-circular edge of the sample being a fixed end and a curved end on the side of the sample close to the diameter of the semi-circle.
[0008] Preferably, the sample has a slit along the semicircular diameter direction, and the cantilever between the slit and the semicircular diameter of the sample is a curved end.
[0009] Preferably, the slit is set parallel to the semicircular diameter of the sample.
[0010] Preferably, the end of the bent end has a cut along its thickness direction, and the blocking part abuts against the side of the bent end away from the fixed end.
[0011] Preferably, a thin area is embedded inward at the root of the curved end.
[0012] Preferably, the thickness of the thin region is 100 nm.
[0013] Preferably, the sample has a diameter of 3 mm and a thickness of 100 μm.
[0014] Preferably, the clamping part is detachably connected to the transmission electron microscope sample rod.
[0015] To achieve the second objective mentioned above, the present invention provides a method for in-situ bending of a transmission electron microscope, comprising the following steps:
[0016] S1. Sample preparation: Cut the sample material into a semi-circular piece, cut a slit in the semi-circular sample to form a curved end, and use an ion thinning instrument to prepare a thin area on the outside of the curved end.
[0017] S2. Fix the prepared sample in the sample cell of the transmission electron microscope sample rod, then install the blocking component on the transmission electron microscope sample rod so that the blocking part of the blocking component abuts against the bent end of the sample, and finally start the transmission electron microscope sample rod.
[0018] The advantages of this invention are:
[0019] (1) This invention can use the original double tilting sample rod of the transmission electron microscope to conduct in-situ force experiments, without the need to design and manufacture a special mechanical research sample rod, which greatly reduces the construction cost of the research platform in related fields and is conducive to the promotion of related technologies and research.
[0020] (2) This invention can use the standard double tilting sample rod of a transmission electron microscope to realize in-situ bending loading real-time observation and research on specific regions of a special sample without the need for a special in-situ sample rod, and has wide applicability to different types of transmission electron microscopes; at the same time, the process of special sample preparation can be realized with the help of conventional sample preparation equipment of transmission electron microscope, which reduces the restrictions on the types of test materials, and is conducive to the promotion of this technology and the popularization of related in-situ electron microscope research.
[0021] (3) By redesigning the sample and specifications, the present invention designs a cantilever structure on the sample and uses the lever principle to apply controllable and continuous deformation to the microstructure of the sample, which helps to improve the success rate of in-situ experiments. It is also suitable for conventional sample preparation tools for transmission electron microscopy bulk samples, making the sample preparation process of the present invention more convenient and more versatile. This is conducive to the widespread dissemination of the experimental method and helps the development of the field of in-situ mechanical research of transmission electron microscopy at home and abroad.
[0022] (4) This invention utilizes the original double-tilted sample rod of the electron microscope to design an in-situ mechanical experimental method, which enables the sample to tilt in two orthogonal directions. This helps to select a specific crystal orientation of the sample for in-situ bending experiments, and helps to improve the accuracy of in-situ microstructure research. Attached Figure Description
[0023] Figure 1 This is a schematic diagram of the structure of the present invention.
[0024] Figure 2 This is a schematic diagram of the sample structure of the present invention.
[0025] Figure 3 This is a schematic diagram of the blocking component structure of the present invention.
[0026] Figure 4 This is a schematic diagram of the transmission electron microscope sample rod structure of the present invention.
[0027] Figure 5 This is a schematic diagram illustrating the principle of sample tilting in this invention.
[0028] The meanings of the symbols marked in the figure are as follows:
[0029] 1-Transmission electron microscope sample rod, 2-Sample cell, 3-Sample, 31-Bent end, 32-Gap, 33-Thin area, 4-Blocking assembly, 41-Clamping part, 42-Blocking part. Detailed Implementation
[0030] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.
[0031] like Figure 1-4 As shown, an apparatus for in-situ bending of a transmission electron microscope includes, in addition to the transmission electron microscope sample rod 1, a blocking assembly 4 and a specially designed sample 3.
[0032] like Figure 3As shown, the blocking component 4 is disposed on the transmission electron microscope sample rod 1 to block the movement of the sample 3, so that the sample 3 has a continuously adjustable stress state, and includes a clamping part 41 and a blocking part 42.
[0033] The clamping part 41 has an inverted "U" shaped structure, that is, it includes a horizontal section and two vertical sections. The two vertical sections are used to clamp and fix the blocking component 4 to the transmission electron microscope sample rod 1, and the distance between the two vertical sections and the horizontal section is adjustable, so as to facilitate the adaptation to different models of transmission electron microscope sample rods 1.
[0034] like Figure 4 As shown, sample 3 is a specially made sample 3, which can be prepared using traditional metal bulk transmission electron microscopy (TEM) sample equipment and methods. Specifically, it is a semi-circular sheet with a diameter conforming to the general dimensions of conventional TEM samples (3 mm in diameter) and can be placed in the sample cell 2 of the TEM sample rod 1. The semi-circular edge of the specially made sample 3 serves as a fixed end, allowing it to be fixed in the sample cell 2. A slit 32 is formed parallel to the semi-circular diameter of the specially made sample 3, and the cantilever between the slit 32 and the semi-circular diameter is a bent end 31. A thin region 33 is created on the outer side of the bent end 31 through grinding. A notch is provided at the top of the bent end 31, so that after the sample 3 is placed in the sample cell 2, a gap remains between the end of the bent end 31 and the inner wall of the sample cell 2, facilitating deformation of the bent end 31 when the sample 3 rotates.
[0035] A method for in-situ bending in transmission electron microscopy is as follows:
[0036] S1. Before the experiment, the in-situ experimental sample needs to be prepared: cut the sample material into slices, grind the sample into thin slices with sandpaper, with a thickness of about 100 micrometers, which can be adjusted according to the physical properties of the sample.
[0037] S2. Using conventional sample preparation punching machines or wire cutting machines for transmission electron microscopy, cut the sample sheet into a semi-circular special sample 3 with the same diameter as the standard sample for transmission electron microscopy (3mm); use a cutting machine to cut a slit 32 parallel to the diameter direction in the special sample 3 without penetrating the sample 3.
[0038] Specifically, the semi-circular end of the specially made sample 3 is the fixed end; the strip-shaped sample area between this gap 32 and the semi-circular diameter of the sample 3 forms a cantilever beam structure, which is the bent end 31;
[0039] S3. Fix the specially made sample 3 on the sample holder of the commercial ion thinning instrument, and place the outer side of the bent end 31 in the ion beam bombardment area of the thinning instrument for ion beam thinning, and prepare a thin region 33 on the outer side of the bent end 31.
[0040] Specifically, the thickness of thin region 33 is about 100 nm, which can be used to observe the microstructure of samples using transmission electron microscopy.
[0041] S4. Before the experiment, the special sample 3 needs to be placed in the sample cell 2 of the transmission electron microscope sample rod, and the cantilever beam structure on the special sample 3 is exposed in the central hole area of the sample cell 2. The clamping part 41 of the blocking component 4 is clamped on the frame of the transmission electron microscope sample rod 1, and the rod end of the blocking part 42 extends into the central hole area of the sample cell 2 and contacts the outside of the bent end 31 of the special sample 3.
[0042] Specifically, in sample cell 2, the angle between the bent end 31 of sample 3 and the axis of rotation of sample cell 2 is less than 90 degrees; the semi-circular arc of the fixed end is tightly attached to the circular inner wall of sample cell 2, and the fixed end of the special sample 3 is fixed between the locking nut and sample cell 2 by the locking nut on sample cell 2, while the bent end 31 of the special sample 3 is suspended in sample cell 2 (e.g., Figure 1 Then install the blocking assembly 4, insert the blocking part 42 on the blocking assembly 4 into the semi-circular gap outside the curved end 31 of the sample cell 2 and the special sample 3, so that the blocking part 42 of the blocking assembly 4 contacts the outside of the curved end 31 (the side away from the fixed end), while the clamping part 41 abuts against the outer edge area on both sides of the transmission electron microscope sample rod 1 and is mechanically fixed to the transmission electron microscope sample rod 1.
[0043] S5. During the experiment, the transmission electron microscope sample rod 1 is placed into the transmission electron microscope sample chamber according to the conventional transmission electron microscope sample loading procedure. By operating the electron microscope to control the tilting of the sample cell 2 on the sample rod, the sample cell 2 and the specially made sample 3 fixed in the cell are tilted synchronously, so as to realize the real-time electron microscope observation and study of the sample under test by continuous in-situ stress loading.
[0044] Specifically, during the tilting process of the specially designed sample 3, since the blocking component 4 is fixed to the sample rod frame and remains stationary, the outer side of the cantilever beam structure (bent end 31) on the sample 3 that is in contact with the blocking component 4 will be squeezed by the blocking component 4, causing the bent end 31 to bend towards the side with the gap 32, thereby generating deformation and stress on the cantilever beam structure of the sample 3. Since the sample cell 2 of the transmission electron microscope can be continuously tilted at small angles, the bending force applied to the sample cantilever beam structure by this method is also continuously adjustable. During the application of the bending force, the thin area 33 on the cantilever beam structure of the sample 3 can be observed with the help of the transmission electron microscope to obtain a real-time in-situ microstructure evolution image during the sample's deformation under stress.
[0045] Sample tilting principle as follows Figure 5As shown, O is the center point of the rotation axis of sample cell 2. Point A (arbitrary point) on the bent end 31 of the specially made sample 3 rotates to point B with sample cell 2 around O. It can be seen that the projection point of point B on OA is closer to point O than point A. Since the bent end 31 is in contact with the blocking part 42 of the blocking component 4, and the blocking part 42 is located in the central hole of sample cell 2 between the bent end 31 and the rotation axis, the blocking part 42 will prevent the projection point of any point on the bent end 31 in the OA plane from approaching the center O. As a result, the bent end 31 is subjected to a bending moment by the blocking part 42 of the blocking component 4 after rotation. The bending moment will cause stress to be generated on the bent end 31 and transmitted to the thin region 33. With the help of transmission electron microscopy, the real-time response of the microstructure of sample 3 to stress can be observed in the thin region 33, and the image acquisition system of transmission electron microscopy can be used to record it in real time, realizing the study of the in-situ bending experiment process of the sample in transmission electron microscopy. Since the sample cell 2 of the transmission electron microscopy sample rod 1 is controlled by a precision electromechanical system, it can complete continuous tilting.
[0046] Therefore, this invention, as a method for applying bending stress to a sample by utilizing the continuous tilting function of the sample rod of a transmission electron microscope, can also realize real-time electron microscopic observation and research of continuous in-situ stress loading on the sample under test.
[0047] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A device for in-situ bending in a transmission electron microscope, characterized in that: The sample (3) is fixed in the sample cell (2) of the transmission electron microscope sample rod (1) and a blocking component (4) for preventing the sample (3) from tilting with the sample cell (2) and causing the sample (3) to deform. The blocking component (4) includes a clamping part (41) and a blocking part (42). The clamping part (41) is connected to the transmission electron microscope sample rod (1) and the blocking part (42) abuts against the bent end (31) of the sample (3). The sample (3) is in the shape of a semi-circular piece. The semi-circular arc edge of the sample (3) is a fixed end, and the sample (3) has a curved end (31) on the side near the semi-circular diameter. The sample (3) has a slit (32) along the semicircular diameter direction, and the cantilever between the slit (32) and the semicircular diameter of the sample (3) is a curved end (31).
2. The device for in-situ bending of a transmission electron microscope according to claim 1, characterized in that: The slit (32) is set parallel to the semicircular diameter of the sample (3).
3. The device for in-situ bending of a transmission electron microscope according to claim 1, characterized in that: The end of the bent end (31) has a cut along its thickness direction, and the blocking part (42) abuts against the side of the bent end (31) away from the fixed end.
4. The device for in-situ bending of a transmission electron microscope according to claim 1, characterized in that: A thin area (33) is embedded inward at the root of the curved end (31).
5. The device for in-situ bending of a transmission electron microscope according to claim 4, characterized in that: The thickness of the thin region (33) is 100 nm.
6. The device for in-situ bending of a transmission electron microscope according to claim 1, characterized in that: The diameter of the sample (3) is 3 mm and the thickness of the sample (3) is 100 μm.
7. The device for in-situ bending of a transmission electron microscope according to claim 1, characterized in that: The clamping part (41) is detachably connected to the transmission electron microscope sample rod (1).
8. A method for preparing an apparatus for in-situ bending in transmission electron microscopy as described in any one of claims 1-7, characterized in that, Includes the following steps: S1. Sample preparation (3): Cut the sample (3) material into a semi-circular piece and form a curved end (31), and use an ion thinning instrument to prepare a thin area (33) on the outside of the curved end (31). S2. Fix the prepared sample (3) in the sample cell (2) of the transmission electron microscope sample rod (1), then install the blocking component (4) on the transmission electron microscope sample rod (1) so that the blocking part (42) of the blocking component (4) abuts against the bent end of the sample (3), and finally start the transmission electron microscope sample rod (1).