In-situ stretching device monitoring system and method applied to field emission transmission electron microscope

Abstract

The invention discloses an in-situ stretching device monitoring system and method applied to a field emission transmission electron microscope, and relates to the technical field of electron microscopes, and the in-situ stretching device monitoring system comprises an integrated seat which comprises a heat conduction core body and a protection shell wrapping the heat conduction core body; the contact pin is inserted into the heat-conducting core body, and at least one end of the contact pin extends outside; the electric heating unit is arranged in the heat conduction core body; the detection part of the temperature-sensitive unit is inserted into the heat-conducting core body; the controller is electrically connected to the electric heating unit and the temperature-sensitive unit; the contact pin is sleeved with a protective sleeve, the end of the contact pin extends out of the protective sleeve, the protective sleeve is located outside the integrated base, and the end of the contact pin is used for making contact with a temperature-induced deformation structure of the in-situ stretching device. The controller is configured to obtain a target stretching amount of a user, and search a preset database to obtain a matched temperature rise control parameter; and the electric heating unit is controlled to work according to the temperature rise control parameter and is controlled to stop working according to a signal fed back by the temperature-sensitive unit. The in-situ stretching device has the effect of improving the control accuracy of the in-situ stretching device.

Description

Technical Field

[0001] This application relates to the field of electron microscopy technology, and in particular to an in-situ stretching device monitoring system and method for use in field emission transmission electron microscopes. Background Technology

[0002] A field emission transmission electron microscope (FET) is a high-resolution, high-magnification electron optical instrument that uses an electron beam with an extremely short wavelength as an illumination source and an electromagnetic lens to focus the image.

[0003] In use, the transmission electron microscope (TEM) sample holder is a small experimental stage for observing nanoscale samples. The sample is often thinned and placed at the front end of the sample holder. The sample holder enters the designated chamber, and after evacuation, a high-energy electron beam penetrates the sample and interacts with it. By collecting the information from the transmitted electrons, the corresponding sample morphology and crystal structure information can be obtained.

[0004] To study the dynamic structure of materials under different environments or working conditions, an in-situ tensile platform is needed to meet the requirements of tensile sample size, maximum sample load, tensile rate, and maximum tensile deformation, so as to achieve simultaneous research on microstructure observation and mechanical property testing under load.

[0005] To perform tensile actions, in-situ stretching stages require linear drive. Existing linear drive methods generally employ: threaded drives, such as lead screw drives; and electromagnetic drives, such as linear motors. Among these, electromagnetic drives are relatively unsuitable due to their field and range limitations, and the samples at the front end of the electron microscope sample rod are often very small. Therefore, lead screw drives are more commonly used. However, due to the material of the lead screw, in addition to being affected by temperature, long-term wear can also interfere with the micro-stretching action, affecting accuracy. To address this, designs utilizing thermal expansion and contraction characteristics for the drive power of in-situ stretching stages have been proposed. However, if this design directly controls the overall ambient temperature of the chamber, there are issues with vacuum conduction lag and regional temperature difference interference. Therefore, this application proposes a new technical solution. Summary of the Invention

[0006] To improve the control accuracy of in-situ stretching devices, this application provides an in-situ stretching device monitoring system and method for field emission transmission electron microscopy.

[0007] In a first aspect, this application provides a monitoring system for an in-situ stretching device used in a field emission transmission electron microscope, employing the following technical solution: A monitoring system for an in-situ stretching device used in a field emission transmission electron microscope includes: An integrated base, comprising a heat-conducting core and a protective shell encasing it; A contact pin is inserted into the heat-conducting core, with at least one end protruding outwards; The electric heating unit is built into the heat-conducting core; The temperature-sensitive unit, whose detection part is inserted into the heat-conducting core; and, The controller is electrically connected to the heating unit and the temperature-sensitive unit; The contact needle is fitted with a protective sleeve and its end extends out of the protective sleeve. The protective sleeve is located outside the integrated base. The end of the contact needle is used to contact the temperature-induced deformation structure of the in-situ stretching device. The controller is configured as follows: Obtain the user's target stretching amount and search the preset database to get the matching temperature control parameters; The heating unit is controlled to operate according to the heating control parameters, and the heating unit is controlled to stop operating according to the signal fed back by the temperature-sensitive unit.

[0008] Optionally, the protective sleeve is a hollow structure and is connected to two liquid flow pipes, at least one of the liquid flow pipes being connected to a liquid cooling source or a liquid cooling circulation mechanism controlled by a controller; The controller is configured as follows: If a new target stretching amount is obtained from the user, the liquid cooling source or liquid cooling circulation mechanism is turned on and the duration is the preset sufficient cooling duration. The liquid cooling source or liquid cooling circulation mechanism shall be shut down after sufficient cooling time. Based on the user's new target stretching amount, the matching temperature control parameters are obtained by searching the preset database; The heating unit is controlled to operate according to the heating control parameters, and the heating unit is controlled to stop operating according to the signal fed back by the temperature-sensitive unit.

[0009] Optionally, if the temperature-induced deformation structure of a certain in-situ tensioning device is constrained to a linear change, the linear plate includes multiple temperature-induced deformation segments, which are connected to each other at one end and have different materials / densities / purities. One end of the straight plate is provided with a multi-output heat source module for transferring heat to each temperature-induced deformation section. The controller is configured as follows: Receive user-uploaded data and store it in the database; wherein, the user-uploaded data includes at least the deformation rate of each temperature-induced deformation segment at multiple different temperatures when it is in contact with the initial standard temperature; If a user initiates a stretch rate performance test request, the target deformation rate is obtained; The database is searched based on the target deformation rate to obtain the matching temperature and temperature-induced deformation segment, and the corresponding multi-output heat source module is activated.

[0010] Optionally, the plurality of temperature-induced deformation segments are thermally connected, and the spacing between the plurality of temperature-induced deformation segments is 5-8 times the width of the temperature-induced deformation segments.

[0011] Optionally, the multi-output heat source module includes a partition plate, the partition plate having a dividing groove adapted to the temperature-induced deformation section, a temperature-induced deformation section being inserted into one heat insulation groove, and the end of the contact pin away from the integrated base extending into one end of the heat insulation groove.

[0012] Optionally, both ends of the contact pin extend out of the integrated seat; the multiple temperature-induced deformation segments are divided into groups of two, and the two temperature-induced deformation segments in the same group are taken from the same substrate; the two temperature-induced deformation segments in the same group are symmetrically distributed and are used to contact both ends of the same contact pin respectively.

[0013] Optionally, the controller is configured as follows: Define the threshold temperature for excessive thermal distortion; If a single active heating reaches the excessive heat distortion temperature threshold, then one instance of excessive use is defined and recorded. If the number of times of excessive use is counted exceeds the preset threshold for irreversible deformation risk, a replacement prompt for vulnerable parts will be output.

[0014] Secondly, this application provides a monitoring method for an in-situ tensile device, employing the following technical solution: A method for monitoring an in-situ stretching device includes in-situ stretching monitoring and control using a monitoring system for an in-situ stretching device applied to a field emission transmission electron microscope.

[0015] In summary, this application has the following beneficial technical effects: the temperature of the heating unit is more concentrated and can be directly transmitted to the temperature-induced deformation structure of the in-situ stretching device through the heat-conducting core and contact pin, resulting in a more timely and less susceptible to interference response to temperature-induced deformation; secondly, the temperature-sensitive unit is integrated near the heating unit and achieves contact through the heat-conducting core, resulting in a more timely and sensitive temperature sensing response, thereby improving the control accuracy of the in-situ stretching device. Attached Figure Description

[0016] Figure 1 This is an application diagram illustrating an embodiment of this application; Figure 2 This is a connection diagram of the controller in this application; Figure 3 This is a schematic diagram of the structure of the multi-output heat source module area of ​​this application.

[0017] Explanation of reference numerals in the attached diagram: 1. Integrated base; 2. Contact pin; 3. Heating unit; 4. Temperature-sensitive unit; 5. Controller; 6. Protective sleeve; 7. Multi-output heat source module; 71. Partition plate. Detailed Implementation

[0018] The following is in conjunction with the appendix Figures 1-3 This application will be described in further detail.

[0019] This application discloses a monitoring system for an in-situ stretching device used in a field emission transmission electron microscope.

[0020] Reference Figure 1 and Figure 2 The monitoring system for the in-situ stretching device used in a field emission transmission electron microscope includes: an integrated base 1, a controller 5, and a contact pin 2, an electrothermal unit 3, and a temperature-sensitive unit 4 installed on the integrated base 1.

[0021] Among them, the integrated base 1 is a composite structure, with a heat-conducting core inside and a protective shell covering the outside. The heat-conducting core can be made of a high thermal conductivity metal, such as copper or silver; the protective shell can be an insulating material or an insulating and heat-insulating material, such as ceramic; the protective shell should have pre-drilled holes to adapt to other structures.

[0022] The contact needle 2 is inserted into the heat-conducting core and at least one end protrudes outward; the contact needle 2 is fitted with a protective sleeve 6 and the end protrudes out of the protective sleeve 6, the protective sleeve 6 is located outside the integrated base 1; the end of the contact needle 2 is fixed to a structural piece for contacting the temperature-induced deformation structure of the in-situ stretching device.

[0023] In this embodiment, the temperature-induced deformation structure of the in-situ stretching device is as follows: a horizontally placed T-plate, which is used to contact the sample and can move laterally; plate A, which is located at the end of the T-plate and abuts against the end of the T-plate; plate B, which is the selected temperature-induced deformation structure, which fixes plate A; plate B is a long strip and is a vertically placed T-plate, with the end of plate B contacting the above-mentioned structural sheet.

[0024] The heating element 3 is built into the heat-conducting core and can be a high-resistance resistor or a PTC; it is important to note that it is insulated from the heat-conducting core. The temperature-sensitive element 4 is also built into the heat-conducting core and can be a thermistor or a temperature sensor.

[0025] The controller 5 is located outside the integrated base 1. It can be an independent control circuit board or it can directly use the original control system of the electron microscope. The controller 5 is electrically connected to the heating unit 3 and the temperature-sensitive unit 4, and is configured as follows: Obtain the user's target stretching amount and search the preset database to get the matching temperature control parameters; The heating unit 3 is controlled to work according to the heating control parameters, and the heating unit 3 is controlled to stop working according to the signal fed back by the temperature-sensitive unit 4.

[0026] Understandably, for the selected B plate mentioned above, the manufacturer should test it before leaving the factory and record the amount of movement (stretching) caused by its deformation at different temperatures, which drives the A plate to push the T plate, so that users can obtain the required stretching by controlling the temperature.

[0027] According to the above configuration, firstly, the temperature of the heating unit 3 is more concentrated and can be directly transmitted to the temperature-induced deformation structure of the in-situ stretching device through the heat-conducting core and contact pin 2, making the temperature-induced deformation response more timely and less susceptible to interference; secondly, the temperature-sensitive unit 4 is integrated near the heating unit 3 and achieves contact through the heat-conducting core, making the temperature sensing response more timely and sensitive, thereby improving the control accuracy of the in-situ stretching device.

[0028] In one embodiment of this application, the protective sleeve 6 serves two purposes: firstly, to reduce the probability of deformation of the excessively thin contact needle 2; and secondly, to enable more flexible and precise temperature control. It also sets the stage for the configuration of the other embodiments described below. Specifically: The protective sleeve 6 is a hollow structure and is connected to two liquid flow pipes. At least one liquid flow pipe is connected to a liquid cooling source or liquid cooling circulation mechanism controlled by the controller 5. The liquid cooling source is, for example, a water tank at a high position with a specified temperature. The liquid cooling circulation mechanism is, for example, a circulating pump connected to the coolant.

[0029] Based on this, controller 5 is configured as follows: If a new target stretching amount is obtained from the user (i.e., the user performs a new stretching control), the liquid cooling source or liquid cooling circulation mechanism is turned on and the duration is the preset sufficient cooling duration; the sufficient cooling duration refers to the preset duration that can fully ensure that the contact needle 2 and its contact structure are cooled to the specified temperature. The liquid cooling source or liquid cooling circulation mechanism is shut down after excessive cooling time; Based on the user's new target stretching amount, the matching temperature control parameters are obtained by searching the preset database; The heating unit 3 is controlled to work according to the heating control parameters, and the heating unit 3 is controlled to stop working according to the signal fed back by the temperature-sensitive unit 4.

[0030] As can be seen from the above, in this embodiment, firstly, the system will reset the relevant structure before each new stretching control is performed by the user to reduce the interference caused by the residual temperature rise from the previous time and improve the control accuracy; secondly, the user can independently perform relatively frequent differentiated stretching control without having to wait for the equipment to cool down naturally based on experience, so it is more flexible to use.

[0031] In one embodiment of this application, the system is applicable to the following situation: the temperature-induced deformation structure of an in-situ tensile device is constrained to a linear change, referred to as a linear plate. The linear plate includes multiple temperature-induced deformation segments, which are interconnected at one end and have different materials / densities / purities; for example: Instead of using plates A and B to push plate T, multiple parallel rectangular temperature-induced deformation segments are used, one end of which is fixed to a vertical end plate. The end plate can be made of the same material as plate T.

[0032] Meanwhile, one end of the linear plate is equipped with a multi-output heat source module 7 for transferring heat to each temperature-induced deformation segment; based on this, the controller 5 is configured as follows: Receive user-uploaded data and store it in the database; wherein, the user-uploaded data includes at least the deformation rate of each temperature-induced deformation segment at multiple different temperatures when it is in contact with the initial standard temperature; If a user initiates a stretch rate performance test request, the target deformation rate is obtained; The database is searched based on the target deformation rate to obtain the matching temperature and temperature-induced deformation segment, and the corresponding multi-output heat source module 7 is activated.

[0033] It is understandable that the aforementioned initial standard temperature can be achieved by using the active liquid cooling design of the protective sleeve 6; thus, users can not only perform various tests on tensile sample size and maximum tensile deformation, but also tests at different tensile rates. It is important to note that the above method does not simply use different heating rates to achieve different stretching amounts. Instead, it employs a specific linear plate and a multi-output heat source module 7 in conjunction with these components, utilizing the differences in temperature between different materials at the same and different temperatures. This is because: First, it is extremely difficult to precisely define the rate of temperature rise; Secondly, in the application scenarios of this system, the changes at the microscopic level are amplified and affected. For thermally deformable structures such as metals, rapid temperature rise and the high position of lattice dislocations can lead to differences in the amount of change, which can easily accumulate errors and interfere with the control accuracy.

[0034] In one embodiment of this application, the end plate that interconnects multiple temperature-induced deformation segments is a heat insulation plate; at the same time, the spacing between the multiple temperature-induced deformation segments is relatively large, such as 5-8 times the width of the temperature-induced deformation segments.

[0035] Based on the above settings, the impact of heat transfer caused by temperature-induced deformation can be reduced and the impact of heat transfer can be delayed, providing a more generous window for observation.

[0036] Furthermore, the multi-output heat source module 7 includes a partition plate 71, which has a partition groove adapted to the temperature-induced deformation section. One temperature-induced deformation section is embedded in one heat insulation groove. The partition plate 71 can be insulated with a material (such as ceramic) or filled with an inert gas for insulation. The end of the contact pin 2 away from the integrated base 1 extends into one end of the heat insulation groove for contacting the temperature-induced deformation section.

[0037] Based on the above settings, the effects of heat transfer between temperature-induced deformation sections can be further reduced.

[0038] In one embodiment of this application, both ends of the contact pin 2 extend out of the integrated base 1; Multiple temperature-induced deformation segments are divided into two groups. The two temperature-induced deformation segments in the same group are taken from the same substrate, which is equivalent to having the same material / density / purity. Two temperature-induced deformation segments of the same group are symmetrically distributed on the end plate and are used to contact the two ends of the same contact needle 2 respectively.

[0039] Based on the above settings, on the one hand, when the T-plate is pushed by the deformation of the temperature-induced deformation section, the force is relatively more uniform; on the other hand, the temperature-induced deformation sections in the same group coordinate with each other (similar to the averaging of momentum), and are less prone to failure than a single temperature-induced deformation section.

[0040] It should be noted that each of the above-mentioned integrated bases 1 has one contact pin 2 to prevent loss of control.

[0041] In another embodiment of this application, controller 5 is configured as follows: Define the threshold temperature for excessive thermal distortion; If a single active heating reaches the excessive heat distortion temperature threshold, then one instance of excessive use is defined and recorded. If the number of times of excessive use is counted exceeds the preset threshold for irreversible deformation risk, a replacement prompt for vulnerable parts will be output.

[0042] The reason for the above settings is that this system is dependent on the temperature-induced deformation structure. At lower temperatures, such as below 80°C, the temperature reduction has little impact on the material. However, if the system repeatedly enters high temperatures, such as several hundred degrees Celsius, and then actively cools down after heating due to the aforementioned settings, a quenching-like effect can be achieved, which will change the material properties. Therefore, this system counts the number of times the above behavior occurs and promptly reminds the user.

[0043] This application also discloses a method for monitoring an in-situ tensioning device.

[0044] The monitoring method for the in-situ stretching device uses a monitoring system for the in-situ stretching device applied to a field emission transmission electron microscope as described in any of the above embodiments to perform in-situ stretching monitoring and control.

[0045] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A monitoring system for an in-situ tensile device applied to a field emission transmission electron microscope, characterized by, The utility model relates to an integrated seat (1) including a heat-conducting core and a protective shell wrapped outside, a contact needle (2) inserted into the heat-conducting core and at least one end extending outside, an electric heating unit (3) built-in the heat-conducting core, a temperature-sensitive unit (4) with a detection part inserted into the heat-conducting core, and a controller (5) electrically connected to the electric heating unit (3) and the temperature-sensitive unit (4). The contact needle (2) is sleeved with a protective sleeve (6) and the end extends out of the protective sleeve (6), the protective sleeve (6) is located outside the integrated seat (1), and the end of the contact needle (2) is used for contacting a temperature-induced deformation structure of an in-situ stretching device. The controller (5) is configured to: obtain a target stretching amount of a user, and find matching temperature rising control parameters from a preset database; control the electric heating unit (3) to work according to the temperature rising control parameters, and control the electric heating unit (3) to stop working according to a signal fed back by the temperature-sensitive unit (4). The protective sleeve (6) is a hollow structure and is communicated with two liquid flow pipes, at least one of the liquid flow pipes is communicated with a liquid cooling source or a liquid cooling circulation mechanism controlled by the controller (5). The controller (5) is configured to: if a new target stretching amount of the user is obtained, control the liquid cooling source or the liquid cooling circulation mechanism to be turned on and the duration to be a preset cooling sufficient duration; the liquid cooling source or the liquid cooling circulation mechanism is turned off after the cooling sufficient duration; find matching temperature rising control parameters from the preset database according to the new target stretching amount of the user; control the electric heating unit (3) to work according to the temperature rising control parameters, and control the electric heating unit (3) to stop working according to a signal fed back by the temperature-sensitive unit (4).

2. The monitoring system for an in-situ tensile device applied to a field emission transmission electron microscope according to claim 1, characterized in that: If a temperature-induced deformation structure of an in-situ stretching device is constrained to be linearly changed, the linear plate includes a plurality of temperature-induced deformation segments, one end of the plurality of temperature-induced deformation segments is connected to each other and is different in material, density and purity. One end of the linear plate is provided with a multi-output heat source module (7) for respectively transmitting heat to each temperature-induced deformation segment. The controller (5) is configured to: receive user uploaded data and store it in a database; wherein the user uploaded data at least includes the deformation rate of each temperature-induced deformation segment when contacted at an initial standard temperature under a plurality of different temperatures; if the user initiates a stretching rate performance test request, a target deformation rate is obtained; according to the target deformation rate, the database is searched to obtain matching temperature, temperature-induced deformation segment, and the multi-output heat source module (7) is correspondingly controlled to work.

3. The monitoring system for an in-situ tensile device applied to a field emission transmission electron microscope according to claim 1, wherein: The plurality of temperature-induced deformation segments are heat-insulatedly connected, and the spacing of the plurality of temperature-induced deformation segments is 5-8 times the width of the temperature-induced deformation segment. The multi-output heat source module (7) includes a partition plate (71) provided with a partition groove matched with the temperature-induced deformation segment, one temperature-induced deformation segment is built-in one heat-insulated groove, and one end of the contact needle (2) away from the integrated seat (1) extends into one end of the heat-insulated groove. Both ends of the contact needle (2) extend out of the integrated seat (1); the plurality of temperature-induced deformation segments are divided into two groups, two temperature-induced deformation segments in the same group are taken from the same substrate; the two temperature-induced deformation segments in the same group are symmetrically distributed and respectively used for contacting both ends of the same contact needle (2). ​ ​ ​ 4. The monitoring system for an in-situ tensile device applied to a field emission transmission electron microscope according to claim 3, wherein: ​ 5. The monitoring system for an in-situ tensile device applied to a field emission transmission electron microscope according to claim 3, wherein: ​ 6. The monitoring system for an in-situ tensile device applied to a field emission transmission electron microscope according to claim 5, wherein: ​ 7. The monitoring system for an in-situ tensile device applied to a field emission transmission electron microscope according to claim 3, wherein: The controller (5) is configured to: define an over-heat deformation temperature threshold value; define an overuse number of times once the active heating reaches the over-heat deformation temperature threshold value, and count; if the counted overuse number of times exceeds a preset irreversible deformation risk threshold value, output a fragile part replacement prompt.

8. A method of monitoring an in-situ stretching apparatus, characterized by: Use the monitoring system of the in-situ tensile device applied to the field emission transmission electron microscope according to any one of claims 1-7 to perform in-situ tensile monitoring and control.

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