Material microscopic corrosion characterization method under comprehensive action of gas, electricity and force

Abstract

The invention relates to a material microscopic corrosion characterization method under the combined action of gas, electricity and force, a sealing chip with an observation window on the surface is used, an energizing electrode is arranged in a sealing cavity of the sealing chip, the energizing electrode comprises a fixed section and a suspended section suspended in the sealing cavity, and the fixed section and the suspended section are arranged on the surface of the sealing chip. The tail end of the suspended section is electrically connected with a sample; an electric control telescopic material layer is arranged on the surface of the electrified electrode and is connected with the signal control electrode; and a ventilation system is arranged in the sealing chip. When in use, the electrifying electrode, the signal control electrode and the ventilation system are started at the same time, and a transmission electron microscope is used for representing the dynamic microscopic corrosion process of a sample in the sealing cavity through the observation window under the simultaneous coupling action of gas, electricity and force. According to the method, the characterization capability of the in-situ transmission electron microscope is expanded, and the method can be applied to microcosmic corrosion evolution process characterization of an electrical material in a real and complex working environment.

Description

Technical Field

[0001] The invention belongs to the technical field of electron microscopes, and in particular relates to a material micro-corrosion characterization method under the comprehensive action of gas, electricity and force. Background Art

[0002] A transmission electron microscope (TEM) uses a high-energy electron beam accelerated by high voltage as an imaging light source, penetrating the sample to achieve microscopic imaging of samples at scales from atomic to micrometers. TEM-based characterization is an important materials characterization technique, and in situ characterization is a method that uses TEM to observe the structural evolution of a material sample at the atomic scale in real time during growth or chemical and physical reactions.

[0003] Material corrosion is widespread across various sectors of the national economy, such as electricity and energy. Economic losses and even safety incidents caused by material corrosion are common, making the study of material corrosion behavior of great significance. Traditional material characterization methods, such as optical microscopy, scanning electron microscopy, and X-ray analyzers, can typically only analyze changes in the micromorphology, structure, and composition of materials before and after corrosion failure under static conditions. Therefore, transmission electron microscopy is required for further analysis.

[0004] However, current in-situ transmission electron microscopy techniques cannot simultaneously apply multiple couplings, such as gas, electricity, and force, which are crucial when analyzing materials in electrical applications. For example, it's often easy to obtain clear results for materials like high-voltage transmission cables when subjected to stress, atmosphere, or current-carrying tests alone. However, when multiple couplings, such as gas, electricity, and force, are applied simultaneously, the corrosion rate can be accelerated compared to applying each action individually, and even new corrosion mechanisms can emerge. Therefore, it's necessary to observe the microscopic failure process in scenarios closer to actual use. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a method for characterizing material micro-corrosion under the combined action of gas, electricity and force, which is used to analyze the failure process and mechanism of materials in electrical-related fields under the combined action of gas, electricity and force simulating real complex working conditions.

[0006] The technical solution adopted by the present invention to solve its technical problems is: to provide a method for characterizing material micro-corrosion under the combined action of gas, electricity and force, using a sealed chip with an observation window on the surface, a top chip and a bottom chip provided in the sealed chip, the bottom chip including a silicon wafer substrate, two mutually perpendicular powered electrodes arranged in the sealed cavity of the sealed chip, the powered electrodes including a fixed section fixed on the silicon wafer substrate and a suspended section suspended in the sealed cavity, the end of the suspended section being electrically connected to the sample; the upper and lower surfaces of the powered electrode are respectively provided with an electrically controlled telescopic material layer, and the electrically controlled telescopic material layer is provided near one end of the silicon wafer substrate. There is a signal control electrode, and the signal control electrode is isolated from the powered electrode by an insulating film; the sealed chip is provided with a ventilation system connected to the internal sealed cavity, and the material micro-corrosion characterization method under the combined action of gas, electricity and force includes the following steps: simultaneously starting the powered electrode, the signal control electrode and the ventilation system, inputting gas into the sealed cavity through the ventilation system, applying an electrical signal to the sample through the powered electrode, controlling the expansion and contraction of the electrically controlled telescopic material layer through the signal control electrode to drive the sample to gradually deform, and using a transmission electron microscope through the observation window to characterize the dynamic micro-corrosion process of the sample in the sealed cavity under the simultaneous coupling of gas, electricity and force.

[0007] Preferably, the sample electrode is made of platinum or gold, has a thickness of 10 to 200 nm, and a length of the suspended segment is 5 to 20 μm.

[0008] Preferably, the electro-strictive material layer is made of piezoelectric ceramics or electrostrictive polymers.

[0009] Preferably, the insulating film is made of silicon dioxide, silicon nitride or aluminum oxide, and has a thickness of 10 to 1000 nm.

[0010] Preferably, an annular sealing rubber ring is provided around the circumference of the sealing cavity, and the sealing rubber ring is made of corrosion-resistant silicone rubber or perfluoroether rubber.

[0011] Preferably, the observation window is provided at the center of the top chip and the bottom chip, and its shape and size correspond to those of the sealed cavity.

[0012] Preferably, the observation window is made of a silicon nitride film with a thickness of 10 to 100 nm.

[0013] Preferably, the powered electrode and the signal control electrode are connected to an external electrical control device via wires passing through the transmission electron microscope sample holder.

[0014] Preferably, the electrical control device for the powered electrode is an electrochemical workstation, a constant voltage or constant current power supply; and the electrical control device for the signal control electrode is a multi-channel signal generator.

[0015] Preferably, the ventilation system includes an air inlet path and an air outlet path provided at both ends of the sealed cavity, the air inlet path and the air outlet path pass through the transmission electron microscope sample rod and are connected to an external gas supply device, and the external gas supply device is used to circulate water vapor, inert gas or corrosive gas into the sealed cavity.

[0016] The present invention achieves the simultaneous introduction of the gaseous environment within a sealed chip and external electrical and mechanical fields during transmission electron microscopy characterization. This allows for the simultaneous application of tensile or shear stresses, the introduction of various atmospheres, and the application of varying voltages or currents to electrical materials. This expands the characterization capabilities of in-situ transmission electron microscopy and can be applied to characterize the microscopic corrosion evolution of electrical materials in complex, realistic operating environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 A top view of a sealed chip bottom chip used for characterizing material micro-corrosion under the combined effects of gas, electricity, and force.

[0018] Figure 2 A top view of a sealed chip used for characterizing material micro-corrosion under the combined effects of gas, electricity, and force.

[0019] Figure 3 Schematic diagram of the sample holder structure for a transmission electron microscope.

[0020] Among them, 1-powered electrode; 2-electrically controlled telescopic material layer; 3-signal control electrode; 4-sample; 5-observation window; 6-chip wire; 7-through hole; 8-sealing rubber ring; 9-silicon wafer substrate; 10-transmission electron microscope sample rod; 11-sample rod wire; 12-air inlet path; 13-air outlet path.

[0021] The same reference numerals in the various drawings represent the same components. DETAILED DESCRIPTION

[0022] Below in conjunction with specific embodiment, further set forth the present invention.Should be understood that these embodiments are only used to illustrate the present invention and are not used in limiting the scope of the present invention.In addition, should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms fall equally within the scope limited by the appended claims of the application.

[0023] The present invention provides a method for characterizing material micro-corrosion under the combined action of gas, electricity and force, using a Figure 1 、 2The sealed chip shown has an observation window 5 on its surface, and a top chip and a bottom chip are provided inside the sealed chip. The bottom chip includes a silicon wafer substrate 9. Two mutually perpendicular powered electrodes 1 are arranged in the sealed cavity of the sealed chip. The powered electrode 1 includes a fixed section fixed on the silicon wafer substrate 9 and a suspended section suspended in the sealed cavity, and the end of the suspended section is electrically connected to the sample 4; the upper and lower surfaces of the powered electrode 1 are respectively provided with an electrically controlled telescopic material layer 2, and the end of the electrically controlled telescopic material layer 2 close to the silicon wafer substrate 9 is provided with a signal control electrode 3, and the signal control electrode 3 is connected to the powered electrode 1. They are isolated by an insulating film; a ventilation system connected to the internal sealed cavity is provided in the sealed chip, and the material micro-corrosion characterization method under the combined action of gas, electricity and force includes the following steps: simultaneously starting the powered electrode 1, the signal control electrode 3 and the ventilation system, inputting gas into the sealed cavity through the ventilation system, applying an electrical signal to the sample 4 through the powered electrode 1, and controlling the expansion and contraction of the electrically controlled telescopic material layer 2 through the signal control electrode 3 to drive the sample 4 to gradually deform, and using a transmission electron microscope through the observation window 5 to characterize the dynamic micro-corrosion process of the sample 4 in the sealed cavity under the simultaneous coupling of gas, electricity and force.

[0024] The electrode of the sample 4 is made of platinum or gold, with a thickness of 10 to 200 nm, and the length of the suspended section is 5 to 20 μm. The material of the electro-telescopic material layer 2 is piezoelectric ceramic or electrostrictive polymer. The material of the insulating film is silicon dioxide, silicon nitride or aluminum oxide, with a thickness of 10 to 1000 nm. An annular sealing rubber ring 8 is provided around the periphery of the sealed cavity, and the material of the sealing rubber ring 8 is corrosion-resistant silicone rubber or perfluoroether rubber. The observation window 5 is provided at the center of the top chip and the bottom chip, and its shape and size correspond to the sealed cavity. The material of the observation window 5 is a silicon nitride film with a thickness of 10 to 100 nm.

[0025] like Figure 3 As shown, the powered electrode 1 and signal control electrode 3 are connected to external electrical control equipment via wires passing through the transmission electron microscope sample holder 10. The electrical control equipment for the powered electrode 1 is an electrochemical workstation or a constant voltage or constant current power supply; the electrical control equipment for the signal control electrode 3 is a multi-channel signal generator. The ventilation system includes an inlet air path 12 and an outlet air path 13 located at both ends of the sealed chamber. These inlet air paths 12 and outlet air paths 13 pass through the transmission electron microscope sample holder 10 and are connected to an external gas supply device, which is used to circulate water vapor, inert gas, or corrosive gas into the sealed chamber.

[0026] The following detailed description of a specific embodiment illustrates the use of the present invention. The in-situ silicon sealing chip employed in the transmission electron microscope (TEM) of the present invention has a sealed cavity structure that maintains a high vacuum state within the TEM while introducing a gaseous environment for the sample 4. The sealing chip is 8 mm long and 5 mm wide, with an observation window 5 on its surface transparent to the electron beam. The sample 4 being characterized is located at the location of the observation window 5, which is a silicon nitride film 30 μm wide, 50 μm long, and 20 nm thick. The entire sealing chip consists of a top chip and a bottom chip, with a 300 nm thick silicone rubber sealing ring 8 between the top and bottom chips forming a sealed cavity. The observation windows 5 on the top and bottom chips are identical in size and position. A pair of mutually perpendicular electrodes 1 for the sample 4 are disposed on the silicon wafer substrate 9 of the bottom chip. The energized electrodes 1 are made of platinum, are 50 nm thick, and have a 15 μm overhang. One end of the powered electrode 1 is fixedly connected to the silicon wafer substrate 9 of the chip, and the other end of the powered electrode 1 is fixedly connected to the aluminum nanobelt sample 4 (100 nanometers long, 30 nanometers wide, and 15 nanometers thick) by focused ion beam (FIB) welding. The powered electrode 1 is a flat strip with the upper and lower surfaces suspended in the air; an electrically controlled telescopic material layer 2 based on piezoelectric ceramics is respectively provided on the upper and lower surfaces of the powered electrode 1, and the electrically controlled telescopic material layer 2 is connected to the signal control electrode 3; the signal control electrode 3 is isolated from the powered electrode 1 by a silicon dioxide insulating film with a thickness of 500 nanometers; the signal control electrode 3 is connected to an external electrical control device through the chip wire 6 and the sample rod wire 11 inside the transmission electron microscope sample rod 10. A ventilation system for gas transmission is provided at both ends of the sealed cavity of the sealed chip. The ventilation system includes an inlet air path 12 and an outlet air path 13 that pass through the silicon wafer substrate 9. Gas flows into the sealed cavity through one through-hole 7 through the inlet air path 12 and flows out from the other through-hole 7 through the outlet air path 13. At the same time, the through-hole 7 is connected to an external gas transmission device via a gas conduit of the sample holder 10 to achieve control of the atmosphere in the sealed cavity.

[0027] In order to realize the failure process of the tested aluminum nanobelt sample 4 under the conditions of stress, corrosion environment and electrical transport in a real complex environment, the tested sample 4 needs to be subjected to the simultaneous effects of the above three factors to accurately analyze the accelerated corrosion of the aluminum sample 4 and the detailed corrosion fracture path of the sample 4. The specific parameters are as follows: (1) 0.1 atmospheres of water vapor is introduced into the chip through the gas delivery system; (2) 10 microamperes of current is applied to the aluminum metal sample 4 using an electrochemical workstation; (3) an excitation signal is applied to the signal control electrode 33 through the electrochemical workstation to drive the piezoelectric ceramic expansion material 2 to undergo a 5 nanometer tensile deformation and generate tensile stress; (4) a transmission electron microscope is used to characterize the dynamic micro-corrosion process of the sample 4 at the chip window under the simultaneous coupling effects of 0.1 atmospheres of water vapor, 10 microamperes of current and tensile stress generated by 5 nanometers of tensile deformation.

Claims

1. A method for characterizing material micro-corrosion under the combined action of gas, electricity and force, characterized in that: A sealed chip with an observation window on its surface is used. The sealed chip is provided with a top chip and a bottom chip. The bottom chip includes a silicon wafer substrate. Two mutually perpendicular powered electrodes are arranged in the sealed cavity of the sealed chip. The powered electrodes include a fixed segment fixed to the silicon wafer substrate and a suspended segment suspended in the sealed cavity. The ends of the suspended segments are electrically connected to the sample. An electrically controlled telescopic material layer is provided on the upper and lower surfaces of the powered electrode, respectively. A signal control electrode is provided on one end of the electrically controlled telescopic material layer close to the silicon wafer substrate. The signal control electrode is isolated from the powered electrode by an insulating film. The sealing chip is provided with a ventilation system connected to the internal sealing cavity. The material micro-corrosion characterization method under the combined action of gas, electricity and force includes the following steps: Simultaneously start the energized electrode, signal control electrode and ventilation system. The gas is input into the sealed cavity through the ventilation system, the electrical signal is applied to the sample through the energized electrode, and the signal control electrode controls the expansion and contraction of the electrically controlled telescopic material layer to drive the sample to gradually deform. The dynamic micro-corrosion process of the sample in the sealed cavity under the simultaneous coupling of gas, electricity and force is characterized through the observation window using a transmission electron microscope.

2. The method for characterizing material micro-corrosion under the combined action of gas, electricity and force according to claim 1, characterized in that: The sample electrode is made of platinum or gold, has a thickness of 10 to 200 nm, and a length of the suspended section is 5 to 20 μm.

3. The method for characterizing material microcorrosion under the combined action of gas, electricity and force according to claim 1, characterized in that: The material of the electro-controlled telescopic material layer is piezoelectric ceramics or electrostrictive polymer.

4. The method for characterizing material microcorrosion under the combined action of gas, electricity and force according to claim 1, characterized in that: The insulating film is made of silicon dioxide, silicon nitride or aluminum oxide, and has a thickness of 10 to 1000 nm.

5. The method for characterizing material micro-corrosion under the combined action of gas, electricity and force according to claim 1, characterized in that: An annular sealing rubber ring is provided around the circumference of the sealing cavity, and the material of the sealing rubber ring is corrosion-resistant silicone rubber or perfluoroether rubber.

6. The method for characterizing material micro-corrosion under the combined action of gas, electricity and force according to claim 1, characterized in that: The observation window is arranged at the center of the top chip and the bottom chip, and its shape and size correspond to those of the sealed cavity.

7. The method for characterizing material microcorrosion under the combined action of gas, electricity and force according to claim 6, characterized in that: The observation window is made of a silicon nitride film with a thickness of 10 to 100 nm.

8. The method for characterizing material micro-corrosion under the combined action of gas, electricity and force according to claim 1, characterized in that: The power-on electrode and the signal control electrode are connected to an external electrical control device through wires passing through the transmission electron microscope sample rod.

9. The method for characterizing material micro-corrosion under the combined action of gas, electricity and force according to claim 8, characterized in that: The electrical control device of the energized electrode is an electrochemical workstation, a constant voltage or constant current power supply; the electrical control device of the signal control electrode is a multi-channel signal generator.

10. The method for characterizing material micro-corrosion under the combined action of gas, electricity and force according to claim 1, characterized in that: The ventilation system includes an air inlet path and an air outlet path provided at both ends of the sealed cavity. The air inlet path and the air outlet path pass through the transmission electron microscope sample holder and are connected to an external air supply device. The external air supply device is used to circulate water vapor, inert gas or corrosive gas into the sealed cavity.

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