Multi-stage in-situ TEM stretching device and system based on mechanical driving

Abstract

The invention provides a multistage in-situ TEM stretching device and system based on mechanical driving, and relates to the field of micro-nano mechanical measurement methods. The multi-stage in-situ TEM stretching device comprises at least two stages of stretching parts, the multiple stages of stretching parts are connected in sequence, and the stretching part of the next stage is used for reducing the displacement loading amount transmitted by the stretching part of the previous stage. At least two stages of stretching parts with different displacement loading step size zooming amounts are combined, so that measuring personnel can accurately measure mechanical load information of the nanoscale test piece, an internal deformation mechanism of the nanoscale test piece is accurately analyzed, a large-range displacement loading range can be realized, and the measurement precision is improved. The device has the advantages of simple structure and high measurement precision. The stretching device is not only suitable for in-situ stretching measurement of metal, ceramic and other block materials, but also suitable for in-situ stretching test and characterization of mechanical properties of graphene, molybdenum disulfide, nanowires, nanotubes and other low-dimensional materials.

Description

Technical Field

[0001] The present invention relates to the field of micro-nanomechanical measurement methods, and in particular to a multi-stage in-situ TEM stretching device and system based on mechanical drive. Background Art

[0002] With the rapid development of micro-nanotechnology, nanoscale materials and structures have been rapidly developed in various fields, such as microelectronic devices, material synthesis, and microelectromechanical sensors. When the size of the material is reduced to the nanoscale, due to the increase in specific surface area, surface forces and electrostatic forces play a dominant role, resulting in some physical and chemical effects, which in turn cause some changes in the material structure, making the material properties at the nanoscale completely different from those at the macroscale. Therefore, it is very important to study the mechanical properties of these nanoscale materials and structures. However, whether in terms of size, function, or manipulation, clamping, and loading, for nanoscale research objects, macroscopic mechanical properties testing equipment and platforms, and traditional measurement methods cannot meet this demand. In-situ transmission electron microscopy provides a good platform for studying material properties. Through the interaction between the electron beam and the sample, the sample area can be magnified by a million times, thereby achieving atomic-scale resolution and fine observation of the test sample. The samples of the traditional Gatan654 in-situ stretching device are generally thinned in the central circular area of ​​the millimeter-scale specimen. The evolution process of the material in the central thin area is observed by stretching the macroscopic specimen. However, this stretching method leads to a complex stress state of the material in the thin area, making it difficult to accurately and quantitatively analyze the nanoscale deformation evolution mechanism of the material.

[0003] At present, the in-situ tensile loading of transmission electron microscopes is mainly carried out through piezoelectric drive loading and V-beam thermal drive loading. The piezoelectric drive method has high precision, but the driving displacement range is small, and the piezoelectric drive method requires the introduction of corresponding microelectronic circuits inside the loading rod, which further limits the universal application of this method in in-situ tensile loading. V-beam thermal drive loading is to make the V-beam expand by resistance heating, and then drive the intermediate mechanism connected to it to produce corresponding displacement. However, this solution requires the use of photolithography to make the corresponding V-shaped drive mechanism, and it is necessary to use ion implantation to introduce resistance to the V-beam. The process is complicated and has a certain service life limit. Therefore, this method is too complicated, resulting in it not being widely used. Summary of the invention

[0004] The present invention provides a multi-stage in-situ TEM stretching device based on mechanical drive, which is used to solve the problems of small displacement range, complex structure and small application range in the prior art.

[0005] The present invention provides a multi-stage in-situ TEM stretching device based on mechanical drive, comprising: At least two levels of tensile components, the displacement loading step scaling amount of the at least two levels of tensile components decreases as the level increases, the multiple levels of tensile components are connected in sequence, the tensile component of the latter level is used to reduce the displacement loading amount transmitted by the tensile component of the former level, and the tensile component of the highest level is connected to the tensile specimen.

[0006] According to the present invention, a multi-stage in-situ TEM stretching device based on mechanical drive is provided, and the stretching device comprises: A primary stretching component, wherein the primary stretching component is provided with a first connecting portion and a second connecting portion; A secondary tensile component is provided with a third connecting portion and a fourth connecting portion, the secondary tensile component is connected to the first connecting portion and the second connecting portion respectively, and the tensile specimen is connected to the third connecting portion and the fourth connecting portion respectively.

[0007] According to a multi-stage in-situ TEM stretching device based on mechanical drive provided by the present invention, the primary stretching component comprises: a first connection component; A second connecting component, the second connecting component is connected in series with the first connecting component, the rigidity of the second connecting component is greater than the rigidity of the first connecting component, and the first connecting part and the second connecting part are arranged on the second connecting component.

[0008] According to a mechanically driven multi-stage in-situ TEM stretching device provided by the present invention, the first connecting component comprises: A first connector body, wherein a first end of the first connector body is provided with a positioning portion, and a second end of the first connector body is provided with a first notch; a first intermediate connecting member, wherein a first end of the first intermediate connecting member is connected to the second connecting assembly, and a second end of the first intermediate connecting member is located in the first notch; A plurality of first connecting beams, a portion of the plurality of first connecting beams is located on one side of the first intermediate connecting member, the remaining portion of the plurality of first connecting beams is located on the other side of the first intermediate connecting member, and the second end of the first intermediate connecting member is connected to the side of the first notch through the first connecting beam.

[0009] According to a mechanically driven multi-stage in-situ TEM stretching device provided by the present invention, a plurality of the first connecting beams are symmetrically arranged in pairs on both sides of the first intermediate connecting member.

[0010] According to a mechanically driven multi-stage in-situ TEM stretching device provided by the present invention, the second connecting component comprises: A second connector body, a first end of the second connector body and a first end of the first intermediate connector; a positioning portion is provided at the second end of the second connector body, a hollow area is provided at the middle of the second connector body, the first connection portion and the second connection portion are spaced apart in the hollow area along the force direction of the second connector body, and are respectively connected to two opposite sides of the hollow area.

[0011] According to a mechanically driven multi-stage in-situ TEM stretching device provided by the present invention, the secondary stretching component comprises: A third connection component; a fourth connecting component, wherein the third connecting component and the fourth connecting component are arranged at intervals; A buffer component is connected to the third connecting component and the fourth connecting component.

[0012] According to a multi-stage in-situ TEM stretching device based on mechanical drive provided by the present invention, the buffer assembly includes a slot and a T-shaped protrusion, the T-shaped protrusion can be movably clamped in the slot, one of the slot and the T-shaped protrusion is connected to the third connecting assembly, and the other of the slot and the T-shaped protrusion is connected to the fourth connecting assembly.

[0013] According to a mechanically driven multi-stage in-situ TEM stretching device provided by the present invention, the third connecting component comprises: A third connecting member body, wherein a second notch is provided on a side of the third connecting member body close to the fourth connecting component; a second intermediate connecting member, wherein a first end of the second intermediate connecting member is connected to the T-shaped protrusion, and a second end of the second intermediate connecting member is located in the second notch; A plurality of second connecting beams, a portion of the plurality of second connecting beams is located on one side of the second intermediate connecting member, the remaining portion of the plurality of second connecting beams is located on the other side of the second intermediate connecting member, and the second end of the second intermediate connecting member is connected to the side of the second notch through the second connecting beam.

[0014] According to a mechanically driven multi-stage in-situ TEM stretching device provided by the present invention, a plurality of the second connecting beams are symmetrically arranged in pairs on both sides of the second intermediate connecting member.

[0015] According to a mechanically driven multi-stage in-situ TEM stretching device provided by the present invention, the fourth connecting component comprises: A fourth connecting member body, wherein a third notch is provided on a side of the fourth connecting member body close to the third connecting component; a first measuring connection member, the first measuring connection member is located in the third notch and connected to the side of the third notch through a plurality of third connecting beams; a first end of the first measuring connection member is connected to the slot; A second measuring connection piece, the second measuring connection piece is located on a side of the first measuring connection piece away from the card slot, the second measuring connection piece is arranged at an interval with the first measuring connection piece, and the second measuring connection piece is connected to the side of the third notch through a fourth connecting beam; the third connecting portion is arranged at an end of the first measuring connection piece close to the second measuring connection piece, and the fourth connecting portion is arranged at an end of the second measuring connection piece close to the first measuring connection piece.

[0016] According to a mechanically driven multi-stage in-situ TEM stretching device provided by the present invention, the plurality of third connecting beams are symmetrically arranged in pairs on both sides of the first measuring connecting member.

[0017] According to a mechanically driven multi-stage in-situ TEM stretching device provided by the present invention, the third connecting beams on the same side of the first measuring connecting member are parallel to each other.

[0018] According to a mechanically driven multi-stage in-situ TEM stretching device provided by the present invention, the first measurement connecting member and the second measurement connecting member are arranged on the same straight line with intervals along the force direction of the second connecting member body.

[0019] The present invention also provides a multi-stage in-situ TEM stretching system based on mechanical drive, comprising a loading rod and any one of the multi-stage in-situ TEM stretching devices based on mechanical drive described above.

[0020] The multi-stage in-situ TEM stretching device based on mechanical drive provided by the present invention is combined by using at least two stages of stretching components with different displacement loading step scaling amounts, so that measurement personnel can accurately measure the mechanical load information of nanoscale specimens, accurately analyze the internal deformation mechanism of nanoscale specimens, and can achieve a wide range of displacement loading ranges, with the advantages of simple structure and high measurement accuracy. The stretching device of the present invention is not only suitable for in-situ stretching measurement of bulk materials such as metals and ceramics, but also suitable for in-situ stretching testing and characterization of mechanical properties of low-dimensional materials such as graphene, molybdenum disulfide, nanowires, and nanotubes. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic structural diagram of a multi-stage in-situ TEM stretching device based on mechanical drive provided by the present invention.

[0023] Figure 2 It is a structural schematic diagram of the primary stretching component provided by the present invention.

[0024] Figure 3 It is a structural schematic diagram of the secondary stretching component provided by the present invention.

[0025] Figure 4 This is a scanning electron microscope image of the mechanically driven multi-stage in-situ TEM stretching device provided by the present invention.

[0026] Figure 5 It is a schematic diagram of the connection relationship between the third connecting portion, the fourth connecting portion and the tensile test piece provided by the present invention.

[0027] Figure 6 This is a physical picture of the Gatan 654 in-situ transmission loading rod provided by the present invention.

[0028] Figure 7 yes Figure 6 Schematic diagram of the local enlarged structure at point A in the middle.

[0029] Reference numerals: 100, primary stretching member; 110, first connecting portion; 120, second connecting portion; 130, first connecting member body; 140, positioning portion; 150, first intermediate connecting member; 160, first connecting beam; 170, second connecting member body; 180, intermediate connecting portion; 200, secondary stretching component; 210, third connecting part; 220, fourth connecting part; 230, buffer assembly; 231, slot; 232, T-shaped protrusion; 240, third connecting member body; 250, second intermediate connecting member; 260, second connecting beam; 270, fourth connecting member body; 280, first measuring connecting member; 281, third connecting beam; 290, second measuring connecting member; 291, fourth connecting beam; 300, Gatan654 in-situ transmission loading rod; 400. Tensile specimen. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In the description of the embodiments of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limitations on the embodiments of the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0032] In the description of the embodiments of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the embodiments of the present invention can be understood according to specific circumstances.

[0033] In the embodiments of the present invention, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "above" and "above" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature being "below", "below" and "below" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0034] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the embodiment of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0035] Combine the following Figures 1 to 7The specific structure and working principle of the multi-stage in-situ TEM stretching device based on mechanical drive of the present invention are described.

[0036] like Figure 1 As shown, the multi-stage in-situ TEM stretching device based on mechanical drive includes at least two stages of stretching components, and the displacement loading step scaling of the at least two stages of stretching components decreases as the level increases, that is, the displacement loading step scaling of the previous stage stretching component is greater than the displacement loading step scaling of the next stage stretching component. The multi-stage stretching components are connected in sequence, and the stretching component of the next stage is used to reduce the displacement loading amount transmitted by the stretching component of the previous stage, and the highest-level stretching component is connected to the stretching specimen 400.

[0037] It should be noted here that the use of "level" to limit the tensile components in the present invention is only to distinguish the different sizes of the displacement loading step scaling of each tensile component, and has no substantial meaning.

[0038] The multi-stage in-situ TEM stretching device based on mechanical drive provided by the present invention is combined by using at least two stages of stretching components with different displacement loading step scaling amounts, so that measurement personnel can accurately measure the mechanical load information of nanoscale specimens, accurately analyze the internal deformation mechanism of nanoscale specimens, and can achieve a wide range of displacement loading ranges, with the advantages of simple structure and high measurement accuracy. The stretching device of the present invention is not only suitable for in-situ stretching measurement of bulk materials such as metals and ceramics, but also suitable for in-situ stretching testing and characterization of mechanical properties of low-dimensional materials such as graphene, molybdenum disulfide, nanowires, and nanotubes.

[0039] In one embodiment of the present invention, Figure 1 and Figure 2 As shown, the stretching device includes a primary stretching component 100 and a secondary stretching component 200. The primary stretching component 100 is provided with a first connection portion 110 and a second connection portion 120; the secondary stretching component 200 is provided with a third connection portion 210 and a fourth connection portion 220. The secondary stretching component 200 is connected to the first connection portion 110 and the second connection portion 120 respectively, and the tensile specimen 400 is connected to the third connection portion 210 and the fourth connection portion 220 respectively. When the primary stretching component 100 is subjected to the displacement load applied by the loading device, the primary stretching component 100 is deformed within the elastic range after being subjected to the force, and the displacement load is reduced and transferred to the secondary stretching component 200. The secondary stretching component 200 is deformed within the elastic range after being subjected to the force, and the displacement load is reduced and transferred to the tensile specimen 400. Of course, the number of levels of the stretching component is not limited to two levels, and can also be three, four or more levels, which is determined according to the measurement accuracy requirements. The more the number of levels of the stretching component, the higher the measurement accuracy.

[0040] In one embodiment of the present invention, the primary tensile component 100 includes a first connecting component and a second connecting component, the second connecting component is connected in series with the first connecting component, the stiffness of the second connecting component is greater than the stiffness of the first connecting component, the first connecting part 110 and the second connecting part 120 are arranged on the second connecting component, and since the stiffness of the second connecting component is greater than the stiffness of the first connecting component, when subjected to a displacement load, the deformation amount of the second connecting component is smaller than the deformation amount of the first connecting component.

[0041] In one embodiment of the present invention, the first connection assembly includes a first connection member body 130, a first intermediate connection member 150 and a plurality of first connection beams 160. The first connection member body 130 mainly serves as a connection and is used to connect with the Gatan 654 in-situ transmission loading rod 300 through a positioning portion. The first end of the first connection member body 130 is provided with a positioning portion 140. In this embodiment, the positioning portion 140 of the first connection member body 130 is a circular threaded hole. Of course, it can also be a positioning protrusion or other positioning structure. During installation, the first connection member body 130 is installed on the Gatan 654 in-situ transmission loading rod 300 through the circular threaded hole. The second end of the first connection member body 130 is provided with a first notch to provide space for the first intermediate connection member 150 and the first connection beam 160.

[0042] The first end of the first intermediate connector 150 is connected to the second connecting assembly, and the second end of the first intermediate connector 150 is located in the first notch. The first intermediate connector 150 is a strip-shaped structure, and the first intermediate connector 150 is arranged along the force direction of the second connector body 170, that is, along Figure 2 The left and right direction settings in .

[0043] The first connection beam 160 is a strip-shaped structure or a sheet-shaped structure, and is used to connect the first intermediate connection member 150 and the first connection member body 130 together. A portion of the plurality of first connection beams 160 is located on one side of the first intermediate connection member 150, and the remaining portion of the plurality of first connection beams 160 is located on the other side of the first intermediate connection member 150. The second end of the first intermediate connection member 150 is connected to two side edges opposite to the first notch through the first connection beam 160. Since the first connection beam 160 has a relatively small rigidity, when subjected to a displacement load, the first connection beam 160 has a relatively large deformation amount.

[0044] In one embodiment of the present invention, a plurality of first connecting beams 160 are symmetrically arranged on both sides of the first intermediate connecting member 150. Specifically, Figure 2As shown, three first connecting beams 160 are arranged on one side of the first intermediate connecting member 150, and three first connecting beams 160 are arranged on the other side of the first intermediate connecting member 150. The three first connecting beams 160 on one side of the first intermediate connecting member 150 are symmetrically arranged with the three first connecting beams 160 on the other side of the first intermediate connecting member 150.

[0045] In one embodiment of the present invention, the second connecting component includes a second connecting member body 170, a first end of the second connecting member body 170 and a first end of the first intermediate connecting member 150, and a positioning portion 140 is provided at the second end of the second connecting member body 170. In this embodiment, the positioning portion 140 of the second connecting member body 170 is a circular threaded hole. Of course, it can also be a positioning protrusion or other positioning structure. During installation, the second connecting member body 170 is installed on the Gatan654 in-situ transmission loading rod 300 through the circular threaded hole.

[0046] A hollow area is provided in the middle of the second connector body 170, and the hollow area is a rectangular area. Of course, it can also be other shapes. By providing a hollow area in the middle of the second connector body 170, two intermediate connecting parts 180 with smaller widths are formed on both sides of the hollow area, and the rigidity of the intermediate connecting part 180 is greater than the rigidity of the first connecting beam 160. When subjected to a displacement load, the deformation amount of the intermediate connecting part 180 is small, thereby reducing the displacement load transmitted to the secondary tensile component 200. In this embodiment, two intermediate connecting parts 180 are provided, and the sizes of the two intermediate connecting parts 180 are equal and symmetrically arranged to facilitate subsequent calculations.

[0047] The first connection part 110 and the second connection part 120 are used to connect the secondary tensile component 200. The first connection part 110 and the second connection part 120 are arranged in the hollow area along the force direction of the second connecting member body 170 at intervals, and are respectively connected to the two opposite sides of the hollow area. During installation, high-strength glue is used to bond the secondary tensile component 200 to the first connection part 110 and the second connection part 120.

[0048] It should be noted here that, in this embodiment, the first connector body 130, the first intermediate connector 150, the first connecting beam 160, the second connector body 170, the first connecting portion 110 and the second connecting portion 120 are all integrated structures, not separate components, that is, the primary stretching component 100 is an integral structure, but is named separately for the convenience of describing the structure. The above components are formed by femtosecond laser processing and etching.

[0049] In a preferred embodiment of the present invention, in order to meet the specimen size requirements of the Gatan 654 in-situ transmission loading rod 300, the length of the primary tensile component 100 is 11.7 mm, the width of the primary tensile component 100 is 2.5 mm, and the thickness of the primary tensile component 100 is 100 μm. Figure 2 As shown, in this embodiment, the primary tensile component 100 is made of tungsten material with a thickness of 100 μm and is made by femtosecond laser etching. Circular threaded holes are set at both ends of the primary tensile component 100. The primary tensile component 100 is fixed to the front end of the Gatan654 in-situ transmission loading rod 300 through two circular threaded holes.

[0050] In one embodiment of the present invention, the secondary tensile component 200 includes a third connecting component, a fourth connecting component and a buffer component 230, and the third connecting component and the fourth connecting component are arranged at intervals along the length direction of the secondary tensile component 200. Of course, in some embodiments, the third connecting component and the fourth connecting component can also be connected by a connecting member with smaller rigidity, and the rigidity of the connecting member is smaller than the rigidity of the second connecting beam 260. The buffer component 230 is connected to the third connecting component and the fourth connecting component. By arranging the buffer component 230 between the third connecting component and the fourth connecting component, it can play a connecting role and a buffering role, so as to prevent the tensile specimen 400 from being damaged due to vibration before loading.

[0051] In one embodiment of the present invention, the buffer assembly 230 includes a slot 231 and a T-shaped protrusion 232. The cross section of the slot 231 is U-shaped, and of course, it can also be C-shaped or other shapes. The T-shaped protrusion 232 is movably clamped in the slot 231, one of the slot 231 and the T-shaped protrusion 232 is connected to the third connecting assembly, and the other of the slot 231 and the T-shaped protrusion 232 is connected to the fourth connecting assembly.

[0052] In one embodiment of the present invention, Figure 3 and Figure 4 As shown, the third connecting component includes a third connecting member body 240, a second intermediate connecting member 250 and a plurality of second connecting beams 260. A second notch is provided on one side of the third connecting member body 240 close to the fourth connecting member; the second intermediate connecting member 250 is a strip-shaped structure, and the second intermediate connecting member 250 is provided along the force direction of the second connecting member body 170, that is, along Figure 3 The first end of the second intermediate connector 250 is connected to the T-shaped protrusion 232, the second end of the second intermediate connector 250 is located in the second notch, and the second end of the second intermediate connector 250 is spaced a certain distance from the third connector body 240.

[0053] A portion of the plurality of second connecting beams 260 is located on one side of the second intermediate connecting member 250, and the remaining portion of the plurality of second connecting beams 260 is located on the other side of the second intermediate connecting member 250. The second end of the second intermediate connecting member 250 is connected to two side edges opposite to the second notch through the second connecting beam 260. The second intermediate connecting member 250 and the second connecting beam 260 cooperate to form a loading buffer beam, which can further prevent the tensile specimen 400 from being damaged due to vibration before loading.

[0054] In one embodiment of the present invention, a plurality of second connecting beams 260 are symmetrically arranged on both sides of the second intermediate connecting member 250. Specifically, Figure 3 As shown, two second connection beams 260 are provided on one side of the second intermediate connection member 250, and two second connection beams 260 are provided on the other side of the second intermediate connection member 250. The two second connection beams 260 on one side of the second intermediate connection member 250 are symmetrically arranged with the two second connection beams 260 on the other side of the second intermediate connection member 250. Of course, the number of the second connection beams 260 on each side of the second intermediate connection member 250 is not limited thereto, and is determined according to actual needs.

[0055] In one embodiment of the present invention, the fourth connection assembly includes a fourth connection member body 270, a first measurement connection member 280 and a second measurement connection member 290. A third notch is provided on one side of the fourth connection member body 270 close to the third connection assembly. The first measurement connection member 280 is a strip-shaped structure. The first measurement connection member 280 is provided along the force direction of the second connection member body 170, that is, along Figure 3 The first measuring connection member 280 is located in the third notch and is connected to two opposite sides of the third notch through a plurality of third connecting beams 281 . The first end of the first measuring connection member 280 is connected to the card slot 231 .

[0056] The second measuring connecting member 290 is in a strip-shaped structure. The second measuring connecting member 290 is arranged along the force direction of the second connecting member body 170, that is, along Figure 3 The second measuring connector 290 is located on the side of the first measuring connector 280 away from the card slot 231, and the second measuring connector 290 is arranged at intervals from the first measuring connector 280. Preferably, the width of the first measuring connector 280 is equal to the width of the second measuring connector 290, and the first measuring connector 280 and the second measuring connector 290 are arranged at intervals on the same straight line along the force direction of the second connector body 170. The second measuring connector 290 is connected to the two side edges opposite to the third notch through the fourth connecting beam 291; the third connecting portion 210 is arranged at one end of the first measuring connector 280 close to the second measuring connector 290, and the fourth connecting portion 220 is arranged at one end of the second measuring connector 290 close to the first measuring connector 280.

[0057] In one embodiment of the present invention, a plurality of third connecting beams 281 are symmetrically arranged on both sides of the first measuring connecting member 280. Two third connecting beams 281 are arranged on one side of the first measuring connecting member 280, and two third connecting beams 281 are arranged on the other side of the first measuring connecting member 280. The two third connecting beams 281 on one side of the first measuring connecting member 280 are symmetrically arranged with the two third connecting beams 281 on the other side of the first measuring connecting member 280. Of course, the number of the third connecting beams 281 on each side of the first measuring connecting member 280 is not limited thereto, and is determined according to actual needs. The third connecting beams 281 on the same side of the first measuring connecting member 280 are parallel to each other, and the length direction of the first measuring connecting member 280 is perpendicular to the length direction of the third connecting beams 281.

[0058] It should be noted here that, in this embodiment, the third connector body 240, the second intermediate connector 250, the second connecting beam 260, the fourth connector body 270, the third connecting beam 281, the fourth connecting beam 291, the first measuring connector 280 and the second measuring connector 290 are all integrated structures, not separate components, that is, the secondary tensile component 200 is an integral structure, but is named separately for the convenience of describing the structure. The above components are formed by femtosecond laser processing and etching.

[0059] In a preferred embodiment of the present invention, Figure 3 As shown, the fourth connecting beams 291 on both sides of the second measuring connecting member 290 are symmetrically arranged, and the fourth connecting beams 291 are in a strip or sheet structure. One end of the two fourth connecting beams 291 is connected to the two side edges opposite to the third notch, that is, Figure 3 The upper side and the lower side of the third notch are connected, and the other ends of the two fourth connecting beams 291 are connected to the two sides of the second measuring connecting member 290 respectively.

[0060] In one embodiment of the present invention, the secondary tensile component 200 is a mechanical load measuring device, the length of the secondary tensile component 200 is 300 μm, the width of the secondary tensile component 200 is 70 μm, the thickness of the secondary tensile component 200 is 10 μm, and the secondary tensile component 200 is processed by femtosecond laser etching. Figure 3 As shown, the secondary tensile component 200 consists of two parts, one part (the fourth connecting component) is the force measuring beam, and the other part (the third connecting component) is the stiffness reduction mechanism. By observing the deflection change of the measuring beam in situ, the mechanical load on the specimen can be calculated. The stiffness reduction mechanism further reduces the external loading displacement, so that the final specimen loading displacement reaches the nanometer level.

[0061] The present invention also provides a design method for a multi-stage in-situ TEM stretching device based on mechanical drive. In order to achieve quantitative in-situ stretching, it is necessary to first design the mechanical properties of each structure. The stiffness design method is introduced here, with stiffness design as an indicator and displacement loading accuracy as a goal for design. The minimum loading step of the Gatan654 in-situ transmission loading rod is 2μm. We cannot directly load the loading step onto the tensile specimen 400, so we need to scale the loading step through the multi-stage in-situ TEM stretching device designed above. All deformation structures work within the elastic range, so each structure of the multi-stage in-situ TEM stretching device is regarded as a spring structure with a certain stiffness. Adopt The first i The stiffness of a partial structure refers to the stiffness of the first intermediate connecting member 150 , the first connecting beam 160 or the intermediate connecting portion 180 . Indicates the first i The stiffness of the partial structure refers to the stiffness of the second connecting beam 260, the second intermediate connecting member 250, the first measuring connecting member 280, the third connecting beam 281, the second measuring connecting member 290 or the fourth connecting beam 291. From the above content, it can be seen that the elongation of the intermediate connecting portion 180 is the displacement load transmitted to the secondary tensile component 200. The intermediate connecting portion 180 of the primary tensile component 100 and the first connecting component are in a series structure, and the two intermediate connecting portions 180 are in a parallel structure. Therefore, the overall stiffness of the primary tensile component is calculated by the following formula (1).

[0062] (1) Overall load on primary tensile component The calculation is performed using the following formula (2).

[0063] (2) in, is the overall deformation of the primary tensile component 100.

[0064] Furthermore, the deformation of the parallel structure formed by the two intermediate connecting parts 180 is calculated using the following formula (3).

[0065] (3) Therefore, it can be seen from the above formula that the tensile displacement transmitted from the primary tensile component 100 to the secondary tensile component 200 is determined by the stiffness proportionality coefficient. The larger the stiffness proportionality coefficient, the smaller the transmitted displacement, so that the displacement loading accuracy of the multi-stage in-situ TEM tensile device is higher. According to the above formula, the corresponding stiffness proportional coefficient can be calculated, and the displacement loading step can be scaled to an accuracy of 10nm.

[0066] Next, the displacement scaling effect of the secondary tensile component is calculated. The displacement loading step length transmitted from the primary tensile component 100 to the secondary tensile component 200 is 10 nm. Then, the displacement loading amount finally transmitted to the tensile specimen 400 is calculated by the following formula (4).

[0067] (4) It can be seen from the above formula (4) that the displacement load finally transmitted to the tensile specimen 400 is also affected by the stiffness proportional coefficient of the secondary tensile component 200: In this embodiment, According to the above formula, the stiffness proportional coefficient can be calculated , the displacement loading step transferred to the tensile specimen 400 is scaled to 1.67 nm. Therefore, the displacement loading step of the multi-stage in-situ TEM tensile device can achieve a loading accuracy of 1.67 nm.

[0068] In order to prepare the in-situ transmission tensile specimen, different preparation and transfer methods of the tensile specimen 400 can be selected according to the characteristics of the tensile specimen. For general metal and ceramic block materials, the FIB sample preparation method is adopted to extract the corresponding micron-level sample from the block, and then the corresponding sample is locally thinned, and finally the sample is transferred between the third connecting part 210 and the fourth connecting part 220 by a high-precision manipulator, and the two ends of the sample are fixed to the third connecting part 210 and the fourth connecting part 220 respectively by FIB ion beam assisted deposition.

[0069] like Figure 5 As shown, for low-dimensional materials such as nanowires, a manipulator device is directly used to complete the transfer under an optical microscope, and the two ends of the nanowire are fixed to the third connecting part 210 and the fourth connecting part 220 by conductive silver glue or FIB ion beam assisted deposition.

[0070] like Figure 6 and Figure 7 As shown, after the in-situ tensile transmission specimen is transferred to the multi-stage in-situ TEM tensile device, the multi-stage in-situ TEM tensile device is loaded onto the Gatan654 in-situ transmission loading rod 300. During the loading process, the loading is performed by the motor drive device provided by the Gatan654. The minimum loading step length of the loading rod is 1 μm. After the multi-stage in-situ TEM tensile device is scaled, the step loading displacement of the tensile specimen 400 can be reduced to nanometer-level accuracy. By observing and recording the deflection change of the force beam, the load magnitude of the tensile specimen 400 can be measured.

[0071] The manufacturing method of the multi-stage in-situ TEM stretching device of the present invention is simple. The multi-stage loading structure design and the introduction of the buffer device have a good protective effect on the ultra-thin tensile specimen 400, and can realize quantitative in-situ tensile deformation testing and load measurement of nanoscale materials at room temperature, achieving a displacement loading step of the order of 1 nm, and is suitable for in-situ TEM stretching characterization of various nanomaterials.

[0072] The present invention also provides a multi-stage in-situ TEM stretching system based on mechanical drive, which includes a loading rod and the multi-stage in-situ TEM stretching device based on mechanical drive described in any one of the above embodiments.

[0073] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A multi-stage in-situ TEM stretching device based on mechanical drive, characterized in that: include: At least two levels of tensile components, the displacement loading step scaling amount of the at least two levels of tensile components decreases as the level increases, the multiple levels of tensile components are connected in sequence, the tensile components of the latter level are used to reduce the displacement loading amount transmitted by the tensile components of the former level, and the tensile components of the highest level are connected to the tensile specimen (400).

2. The mechanically driven multi-stage in-situ TEM stretching device according to claim 1, characterized in that: The stretching device comprises: A primary stretching component (100), wherein the primary stretching component (100) is provided with a first connecting portion (110) and a second connecting portion (120); A secondary tensile component (200), wherein the secondary tensile component (200) is provided with a third connecting portion (210) and a fourth connecting portion (220), the secondary tensile component (200) is connected to the first connecting portion (110) and the second connecting portion (120), respectively, and the tensile specimen (400) is connected to the third connecting portion (210) and the fourth connecting portion (220), respectively.

3. The mechanically driven multi-stage in-situ TEM stretching device according to claim 2, characterized in that: The primary stretching component (100) comprises: a first connection component; A second connecting component, the second connecting component is connected in series with the first connecting component, the rigidity of the second connecting component is greater than the rigidity of the first connecting component, and the first connecting portion (110) and the second connecting portion (120) are arranged on the second connecting component.

4. The mechanically driven multi-stage in-situ TEM stretching device according to claim 3, characterized in that: The first connection component comprises: A first connecting member body (130), wherein a first end of the first connecting member body (130) is provided with a positioning portion (140), and a second end of the first connecting member body (130) is provided with a first notch; a first intermediate connecting member (150), wherein a first end of the first intermediate connecting member (150) is connected to the second connecting assembly, and a second end of the first intermediate connecting member (150) is located in the first notch; A plurality of first connecting beams (160), a portion of the plurality of first connecting beams (160) being located on one side of the first intermediate connecting member (150), a remaining portion of the plurality of first connecting beams (160) being located on the other side of the first intermediate connecting member (150), and a second end of the first intermediate connecting member (150) being connected to a side edge of the first notch via the first connecting beam (160).

5. The mechanically driven multi-stage in-situ TEM stretching device according to claim 4, characterized in that: A plurality of the first connection beams (160) are symmetrically arranged in pairs on both sides of the first intermediate connection member (150).

6. The mechanically driven multi-stage in-situ TEM stretching device according to claim 4, characterized in that: The second connection component comprises: A second connector body (170), a first end of the second connector body (170) and a first end of the first intermediate connector (150); a positioning portion (140) is provided at the second end of the second connector body (170), a hollow area is provided in the middle of the second connector body (170), the first connector (110) and the second connector (120) are arranged in the hollow area at intervals along the force direction of the second connector body (170), and are respectively connected to two opposite sides of the hollow area.

7. The mechanically driven multi-stage in-situ TEM stretching device according to claim 6, characterized in that: The secondary stretching component (200) comprises: A third connection component; a fourth connecting component, wherein the third connecting component and the fourth connecting component are arranged at intervals; A buffer component (230), the buffer component (230) being connected to the third connecting component and the fourth connecting component.

8. The mechanically driven multi-stage in-situ TEM stretching device according to claim 7, characterized in that: The buffer assembly (230) comprises a slot (231) and a T-shaped protrusion (232); the T-shaped protrusion (232) is movably mounted in the slot (231); one of the slot (231) and the T-shaped protrusion (232) is connected to the third connection assembly; and the other of the slot (231) and the T-shaped protrusion (232) is connected to the fourth connection assembly.

9. The mechanically driven multi-stage in-situ TEM stretching device according to claim 8, characterized in that: The third connection component comprises: A third connecting member body (240), wherein a second notch is provided on a side of the third connecting member body (240) close to the fourth connecting component; a second intermediate connecting member (250), wherein a first end of the second intermediate connecting member (250) is connected to the T-shaped protrusion (232), and a second end of the second intermediate connecting member (250) is located in the second notch; A plurality of second connecting beams (260), a portion of the plurality of second connecting beams (260) being located on one side of the second intermediate connecting member (250), a remaining portion of the plurality of second connecting beams (260) being located on the other side of the second intermediate connecting member (250), and a second end of the second intermediate connecting member (250) being connected to a side edge of the second notch via the second connecting beam (260).

10. The mechanically driven multi-stage in-situ TEM stretching device according to claim 9, characterized in that: A plurality of the second connection beams (260) are symmetrically arranged in pairs on both sides of the second intermediate connection member (250).

11. The mechanically driven multi-stage in-situ TEM stretching device according to claim 8, characterized in that: The fourth connection component comprises: A fourth connecting member body (270), wherein a third notch is provided on a side of the fourth connecting member body (270) close to the third connecting component; a first measuring connection piece (280), the first measuring connection piece (280) being located in the third notch and connected to a side edge of the third notch via a plurality of third connection beams (281); a first end of the first measuring connection piece (280) being connected to the clamping slot (231); a second measuring connection piece (290), the second measuring connection piece (290) being located at a side of the first measuring connection piece (280) away from the clamping slot (231), the second measuring connection piece (290) being arranged at an interval from the first measuring connection piece (280), the second measuring connection piece (290) being connected to a side edge of the third notch via a fourth connecting beam (291); the third connecting portion (210) being arranged at an end of the first measuring connection piece (280) close to the second measuring connection piece (290), and the fourth connecting portion (220) being arranged at an end of the second measuring connection piece (290) close to the first measuring connection piece (280).

12. The mechanically driven multi-stage in-situ TEM stretching device according to claim 11, characterized in that: The plurality of third connection beams (281) are symmetrically arranged in pairs on both sides of the first measurement connection member (280).

13. The mechanically driven multi-stage in-situ TEM stretching device according to claim 12, characterized in that: The third connection beams (281) on the same side of the first measurement connection member (280) are parallel to each other.

14. The mechanically driven multi-stage in-situ TEM stretching device according to claim 11, characterized in that: The first measurement connection member (280) and the second measurement connection member (290) are arranged on the same straight line at intervals along the force direction of the second connection member body (170).

15. A multi-stage in-situ TEM stretching system based on mechanical drive, characterized in that: It comprises a loading rod and a mechanically driven multi-stage in-situ TEM stretching device as claimed in any one of claims 1 to 14.

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