A montmorillonite Young's modulus partition programmable regulation method

Abstract

This application provides a method for partitioned programmable control of the Young's modulus of montmorillonite, belonging to the field of laser-matter interaction. The system fixes montmorillonite on a stage and uses an ultrashort pulse laser to emit light, which is then focused onto the surface of the montmorillonite sample by passing it sequentially through a beam expander, a spatial modulator, a sampling mirror, a reflecting mirror, and a scanning galvanometer. The method controls the scanning galvanometer to perform a partitioned matrix scanning of the montmorillonite surface. Utilizing the ultrafast photon energy deposition induced by the ultrashort pulse laser, the photons induce strong multiphoton absorption and transient carrier excitation in the montmorillonite, resulting in nonlinear effects and a significant enhancement of the Young's modulus. The system and method for partitioned programmable control of the Young's modulus of montmorillonite in this application provide a reliable processing method for expanding the applications of montmorillonite.

Description

Technical Field

[0001] This application relates to the field of laser-matter interaction, and more specifically, to a method for partitioned programmable control of Young's modulus of montmorillonite. Background Technology

[0002] Montmorillonite is a layered hydrated aluminosilicate mineral and the most representative host phase in the bentonite system. Its wide distribution, clean and environmentally friendly nature, large reserves, and relatively low mining and processing costs give it a natural advantage and industrial feasibility in the development of low-cost, environmentally friendly functional materials. Montmorillonite consists of regularly stacked layered crystalline sheets with exchangeable cations (such as Na⁺, Ca²⁺, Li⁺, etc.) and a certain amount of interlayer bound water between the layers. This interlayer system exhibits a coupling system of ion-hydration structure and layer charge. The interlayer structure is mainly maintained by weak interactions: long-range forces dominated by Coulomb forces on one hand, and short-range forces mainly contributed by van der Waals forces on the other. The effective bond energy of the interlayer interactions is weak and easily dissociated. When subjected to external factors, its layered structure is prone to plastic deformation, resulting in a significant reduction in the impact toughness of montmorillonite, which greatly limits its applications.

[0003] Modifying montmorillonite to improve its Young's modulus helps expand its application areas. Modified montmorillonite can serve as a supercapacitor membrane framework, simultaneously endowing the framework with excellent impact toughness and load-bearing capacity, effectively resisting impact loads and meeting mechanical load support requirements. It can also be used as a high-strength nanosheet filler dispersed in a ceramic matrix; its layered structure can absorb thermal stress or improve impact toughness to a certain extent, making the ceramic less prone to cracking under extreme environments.

[0004] Currently, common methods for controlling the Young's modulus of montmorillonite include organic modification, inorganic modification, acid modification, composite modification, and heat treatment. These methods, on the one hand, are difficult to precisely control the degree of modification, easily leading to inhomogeneity in the crystal structure; on the other hand, they have requirements regarding sample shape, are sensitive to environmental conditions, have poor repeatability, and offer limited control over the Young's modulus of montmorillonite, typically increasing it by 10%-30%. Summary of the Invention

[0005] To address the aforementioned issues, this application proposes a method for partitioned programmable control of Young's modulus of montmorillonite. This method is characterized by its simplicity, repeatability, and lack of additional chemical additives, providing a new strategy for the development of low-cost and environmentally friendly functional materials.

[0006] According to a specific embodiment of this application, this application provides a method for partitioned programmable control of the Young's modulus of montmorillonite, comprising the following steps: S1, the pulsed laser emitted by the picosecond pulsed laser passes sequentially through a beam expander, a spatial light modulator, a sampling mirror, a first reflecting mirror, a second reflecting mirror, a third reflecting mirror, and a scanning galvanometer to irradiate montmorillonite. The montmorillonite is placed above the platform. The two beams split off by the sampling mirror are collected and recorded by an energy meter and a beam quality analyzer, respectively, to monitor the energy and spot size of the main optical path in real time. S2, the laser energy incident on the montmorillonite is controlled by a computer control system. E in Adjustments are made to perform partitioned matrix pulsed laser scanning of the montmorillonite with different energies, and the laser energy density irradiated onto the montmorillonite is obtained based on the laser spot area A irradiated onto the montmorillonite. F Laser energy density F = E in / A ; S3, control the laser parameters of the picosecond pulse laser so that the total energy inside the montmorillonite satisfies the following relationship: in, F It is energy density. t p Pulse width, It is the laser spot radius. t 0 The peak position of the first laser pulse, R a It is the material's reflectivity. , It is the penetration depth. E It is the Young's modulus of the material. v It is Poisson's ratio. π Pi G Electronic lattice coupling coefficient, t Time variable, c The speed of light in a vacuum x and y The coordinate components of the target point in the laser action plane relative to the center of the laser spot in two orthogonal directions are: x direction and y The directions are perpendicular to each other and lie within the plane of laser action. Coefficient of thermal expansion; S4. The scanning galvanometer is controlled by the computer control system to perform a partitioned matrix scan of the montmorillonite; the temperature of different regions of the montmorillonite is monitored in real time by a spot temperature analyzer to prevent the laser energy from being too high during the irradiation of the montmorillonite, which could cause irreversible damage to the crystal structure.

[0007] In some embodiments, the method further includes: The Young's modulus of the montmorillonite after picosecond pulsed laser scanning was measured using a synchronous nanoindentation apparatus.

[0008] In some embodiments, the pulse width of the picosecond pulsed laser is 10-15 ps; In some embodiments, the incident laser spot is adjusted by the spatial light modulator to be a Gaussian spot with a spatial Gaussian distribution.

[0009] In some embodiments, the wavelength of the laser emitted by the picosecond pulsed laser includes 355nm, 532nm and 1064nm, the repetition frequency is 50kHz to 400kHz and the scanning speed is 100mm / s to 800mm / s.

[0010] In some embodiments, a computer control system controls the scanning galvanometer to scan different regions of the montmorillonite along a preset moving trajectory.

[0011] In some embodiments, the scanning galvanometer is controlled by a computer control system to irradiate each region with the same energy of laser, or to perform laser scanning with different energies according to a preset target region.

[0012] In some embodiments, the preset movement trajectory is at least one of the following: cross scan, back-shaped scan, or zigzag scan.

[0013] In some embodiments, the first reflector, the second reflector, and the third reflector are 45-degree reflectors.

[0014] In some embodiments, after picosecond laser scanning, the Young's modulus of the montmorillonite increases from a maximum of 3.092 GPa to 42.481 GPa.

[0015] Compared with the prior art, the above-described solutions of this application have at least the following beneficial effects: The Young's modulus of montmorillonite after laser scanning is precisely measured using a nanoindenter. The measurement results are fed back to the laser source control system in real time. Based on this feedback data, the laser source dynamically adjusts its output laser parameters to ensure that the physical response of the material can be precisely controlled during laser irradiation. This adjustment process will continue until the system controls the Young's modulus of the material to achieve the predetermined target effect.

[0016] By employing a partitioned matrix scanning method and beam spot adjustment, precise energy distribution during laser irradiation can be achieved, ensuring uniform energy input to each region. In traditional laser processing, the non-uniformity of Gaussian energy distribution often leads to temperature gradients on or within the material surface. This spatial non-uniformity of heat deposition can cause thermal stress concentration, resulting in thermal cracking, deformation, or other unforeseen damage. With the partitioned matrix scanning method, each region can be scanned once or multiple times along a preset path, ensuring uniform laser energy coverage. Simultaneously, the intensity distribution characteristics of the Gaussian beam spot cause energy to gradually attenuate from the center to the edge, avoiding excessive energy concentration or uneven distribution. This optimization not only reduces unnecessary energy waste but also improves the effectiveness of each laser irradiation, allowing the laser energy to be more concentrated on the target area.

[0017] Picosecond lasers, due to their extremely short pulse width, can generate stronger nonlinear optical effects in the interaction between laser and matter. These effects can enhance the absorption rate of laser on the material surface, thereby improving the processing accuracy and efficiency. Furthermore, picosecond pulsed lasers can excite a rapid response in the electronic and phonon systems of montmorillonite, promoting the reconstruction of its microstructure and enhancing its performance. Pulsed lasers can provide finer spatial resolution and faster response times, avoiding the excessive heat accumulation and thermal diffusion generated during irradiation by continuous or long-pulse lasers.

[0018] This application presents a partitioned programmable control method for Young's modulus of montmorillonite, which has broad applicability and can adapt to montmorillonite samples of various shapes and sizes. Regardless of different geometries, sizes, or surface conditions, it can effectively and accurately control Young's modulus. This method fully considers the diversity of montmorillonite samples, ensuring efficient and precise control without imposing any additional restrictions on the shape and structure of the montmorillonite. Whether the montmorillonite sample is blocky, thin film, granular, or has other special forms, this system can flexibly handle it and adjust parameters according to the actual situation of the sample, achieving real-time monitoring and control of Young's modulus. Attached Figure Description

[0019] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application. It is obvious that the drawings described below are merely some embodiments of this application, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort. In the drawings: Figure 1 A flowchart illustrating a method for partitioned programmable control of Young's modulus of montmorillonite provided in some embodiments of this application; Figure 2 This is a schematic diagram of the method for partitioned programmable control of Young's modulus of montmorillon in this application. Figure 3 Schematic diagram of partitioned matrix scanning method and laser preset movement trajectory cross-fill, square-shaped fill, and zigzag fill; Figure 4 The images show the original montmorillonite from this application and the nanoindentation patterns of the montmorillonite obtained after scanning in this example.

[0020] Figure labeling: 1-Picosecond pulsed laser, 2-Beam expander, 3-Spatial modulator, 4-Sampling mirror, 5-First reflecting mirror, 6-Second reflecting mirror, 7-Third reflecting mirror, 8-Scanning galvanometer, 9-Montmorillonite, 10-Platform, 11-Nanoindenter, 12-Spot temperature analyzer, 13-Energy meter, 14-Beam quality analyzer, 15-Computer control system. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this application clearer, the application will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0022] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that an article or device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such an article or device. Without further limitation, an element defined by the phrase "comprising one" does not exclude the presence of other identical elements in the article or device that includes said element.

[0023] The following is in conjunction with the appendix Figure 1-4 Detailed description of optional embodiments of this application.

[0024] like Figure 1 As shown, this application provides a method for partitioned programmable control of Young's modulus of montmorillonite, comprising the following steps: S1, the pulsed laser emitted by the picosecond pulsed laser 1 passes sequentially through the beam expander 2, spatial light modulator 3, sampling mirror 4, first reflecting mirror 5, second reflecting mirror 6, third reflecting mirror 7 and scanning galvanometer 8 to irradiate montmorillonite 9. The montmorillonite 9 is placed above the platform 10. The two beams of light split off by the sampling mirror 4 are collected and recorded by the energy meter 13 and the beam quality analyzer 14, respectively, to monitor the energy and spot size of the main optical path in real time. S2, the laser energy incident on the montmorillonite 9 is controlled by the computer control system 15. E in Adjustments are made to perform partitioned matrix pulsed laser scanning of the montmorillonite 9 with different energies, and the laser energy density irradiated onto the montmorillonite 9 is obtained based on the spot area A irradiated onto the montmorillonite 9. F Laser energy density F = E in / A ; S3, control the laser parameters of the picosecond pulse laser so that the total energy inside the montmorillonite 9 satisfies the following relationship: in, F It is energy density. t p Pulse width, It is the laser spot radius. t 0 The peak position of the first laser pulse, R a It is the material's reflectivity. , It is the penetration depth. E It is the Young's modulus of the material. v It is Poisson's ratio. π Pi G Electronic lattice coupling coefficient, t Time variable, c The speed of light in a vacuum x and y The coordinate components of the target point in the laser action plane relative to the center of the laser spot in two orthogonal directions are: x direction and y The directions are perpendicular to each other and lie within the plane of laser action. Coefficient of thermal expansion; S4, the scanning galvanometer 8 is controlled by the computer control system 15 to perform a partitioned matrix scan on the montmorillonite 9; the temperature of different regions of the montmorillonite 9 is monitored in real time by the spot temperature analyzer 12 to prevent the laser energy from being too high during the irradiation of the montmorillonite, which could cause irreversible damage to the crystal structure.

[0025] Please see Figure 2The programmable control system for Young's modulus of montmorillonite includes a picosecond pulse laser 1, a beam expander 2, a spatial modulator 3, a sampling mirror 4, a first reflecting mirror 5, a second reflecting mirror 6, a third reflecting mirror 7, a scanning galvanometer 8, montmorillonite 9, a platform 10, a nanoindenter 11, a spot temperature analyzer 12, an energy meter 13, a beam quality analyzer 14, and a computer control system 15.

[0026] During system operation, the optical path is as follows: the picosecond pulse laser emitted by the picosecond pulse laser 1 illuminates the beam expander 2, passes through the spatial light modulator 3, and then illuminates the sampling mirror 4. The picosecond pulse laser is sampled, splitting the laser beam into two beams with identical characteristics to the first pulse laser. The output laser energy parameters and spot size of each pulse laser beam are monitored and recorded in real time by the energy meter 13 and the beam quality analyzer 14. The pulse laser is transmitted through the first reflecting mirror 5 to the second reflecting mirror 6, then illuminates the third reflecting mirror 7, and finally illuminates the scanning galvanometer 8, focusing it onto the montmorillonite 9. Finally, the spot temperature analyzer 12 monitors the temperature of different areas in real time to prevent excessive laser energy during montmorillonite irradiation, which could cause irreversible damage to the crystal structure.

[0027] Furthermore, after the montmorillonite is subjected to picosecond laser irradiation, the Young's modulus of the montmorillonite is measured using a nanoindenter 11.

[0028] The loading process involves applying a small, sharp tip, typically made of diamond, with known geometric and elastic properties (such as Poisson's ratio and Young's modulus) to the sample surface. During the indentation process, the applied load is simultaneously recorded. F ) and the resulting indentation depth ( h Analysis of the load-depth curves, particularly using the Oliver and Pharr methods, allows for the extraction of Young's modulus from the sample. This is used to calculate the reduced modulus. E r Contact stiffness S Defined as the slope of the initial portion of the unloading curve at the maximum indentation depth: (1) So E r It can be calculated as follows: (2) in, β A dimensionless correction factor representing the geometry of the indenter tip. A c This represents the projected contact area, which can be determined using an indenter area function calibrated on a standard material (e.g., fused silica). The contact area is defined as: (3) in C j (j=0, 1, 2) are constants determined based on the needle tip calibration results, parameters h c It is the depth of contact: (4) F max It is the maximum load. It is the geometric constant of the indenter.

[0029] To explain the elastic deformation that occurs in the non-rigid indenter and specimen, the Hertz contact theory of non-adhesive elastic contact is used to extract the Young's modulus of the sample: (5) in E and v These are the Young's modulus and Poisson's ratio of the sample. E i and ν i These are the same parameters for the indenter. For diamond indenters, E i and ν i The values ​​are 1141 GPa and 0.07, respectively, and the Poisson's ratio of montmorillonite is 0.36.

[0030] Furthermore, the pulse width of the picosecond pulsed laser is preferably 10-15 ps. When the above pulse width range is adopted, significant nonlinear effects such as multiphoton absorption and transient carrier excitation can be generated during the interaction between the laser and montmorillonite. At the same time, processing efficiency is taken into account while ensuring the single-pulse energy output capability, which is conducive to achieving stable control of the processing process and improving processing quality.

[0031] Furthermore, the spatial light modulator only needs to be able to adjust the incident laser spot to a Gaussian spot with a spatial Gaussian distribution.

[0032] Furthermore, the preferred wavelength of the laser emitted by the picosecond pulsed laser can be 355nm, 532nm, and 1064nm, the preferred repetition frequency is 50kHz to 400kHz, and the preferred scanning speed is 100mm / s to 800mm / s.

[0033] Furthermore, in this example, the energy meter is located in the optical path of the sampling laser beam output by the sampling mirror. The energy meter is used to collect and record the picosecond laser energy emitted by the picosecond pulse laser and monitor it in real time. The beam quality analyzer is set in the optical path of the laser beam sampled by the sampling mirror. The beam quality analyzer is used to monitor, collect, and record the size of the picosecond laser spot emitted by the picosecond pulse laser in real time. The spot temperature analyzer is used to monitor the temperature of the picosecond pulse laser modified area in real time to prevent the laser energy from being too high during the irradiation of montmorillonite, which could cause irreversible damage to the crystal structure.

[0034] Furthermore, the scanning galvanometer can be a commonly used scanning galvanometer in the field of optics, as long as it can control the trajectory of the first laser beam and enable the first laser beam to perform uniform scanning on the montmorillonite.

[0035] Furthermore, in this embodiment, the first reflector 5, the second reflector 6, and the third reflector 7 are 45-degree reflectors.

[0036] Furthermore, the sampling mirror is placed in the optical path of the picosecond laser to sample the laser beam. As long as it can be divided into a laser beam with exactly the same characteristics as the first pulse laser, the monitoring unit can monitor and record the parameters of the first laser beam in real time.

[0037] Please see Figure 3 In this embodiment, a partitioned matrix scanning strategy is used to scan the surface of the montmorillonite sample zone by zone. The laser beam movement trajectory of each zone is at least one of the following: cross-filling, zigzag filling, or Z-shaped filling.

[0038] In some embodiments, after scanning of montmorillonite 9, the Young's modulus of montmorillonite 9 is further measured using a nanoindenter 11.

[0039] The following describes the method and test data for partitioned programmable control of Young's modulus of montmorillonite provided in this application through specific embodiments: Example This embodiment of a method for partitioned programmable control of Young's modulus of montmorillonite includes: conducting montmorillonite irradiation experiments using a laser with an adjustable repetition frequency of 1-1000kHz, a pulse width of 10ps, a center wavelength of 355nm, a maximum single pulse energy of 30μJ, a beam expander, a Meadowlark Optics spatial light modulator, a sampling mirror, a reflector, a scanning galvanometer, a platform, a LabMax-TOP energy meter, an SP204 beam quality analyzer, a spot temperature analyzer, and a Hysitron TS 77 nanoindenter.

[0040] The picosecond pulsed laser emits ultraviolet laser light at a wavelength of 355nm, operates in pulsed mode, and has an output pulse width set to 10ps and a focal radius ω0 of 4.5μm (1 / e 2 ).

[0041] Montmorillonite is a calcium-based montmorillonite with a purity of 80%. During preparation, it is processed into a cylinder with a diameter of 18 mm and a thickness of 8 mm.

[0042] The energy meter collects, records, and monitors the picosecond laser energy emitted by the picosecond pulse laser in real time; the beam quality analyzer monitors, collects, and records the picosecond laser spot size emitted by the picosecond pulse laser in real time; when the output energy or spot size of the picosecond pulse laser does not meet the set value, the picosecond pulse laser is adjusted in time until both the output energy and spot size of the picosecond pulse laser meet the set value.

[0043] In this embodiment, after scanning the montmorillonite with a picosecond pulsed laser, a nanoindenter is used to test the Young's modulus of the montmorillonite after the picosecond pulsed laser treatment. Specifically, after laser scanning, the montmorillonite sample is first polished without damaging the integrity of the surface structure before nanoindentation. Before indentation, the sample surface is pre-screened by optical microscopy, and relatively flat and smooth areas are selected for indentation testing to reduce the interference of surface roughness and defects on the results. Five indentation points are tested for each sample. To avoid the interaction of plastic influence zones of adjacent indentations and to improve statistical representativeness, the center distance between adjacent indentation points is controlled to be no less than 30 μm. At the same time, areas with visible surface defects (such as cracks, contaminants, etc.) are avoided to ensure the resolvability of the load-displacement curve and the repeatability of the results. Considering that montmorillonite particles may cause indenter contamination or damage, after completing five indentations for each sample, four additional indentation point tests are performed on a calibration standard sample (fused silica) to verify the indenter status and calibration. If the test results of fused silica deviate from its expected mechanical parameters, it is determined that there may be indenter contamination, and the corresponding data of the sample are discarded; then the indenter is cleaned, inspected, and recalibrated before continuing subsequent tests. Young's modulus is obtained from the load-displacement curve based on the Oliver-Pharr method; indentation points showing obvious abnormal contact behavior or abnormal curve morphology are rejected.

[0044] Please see Figure 4 The load-displacement curve of the original montmorillonite and the method of Young's modulus control of montmorillonite in this embodiment are shown at 12 J / cm. 2Load-displacement curves of montmorillonite obtained after the lower treatment. The interlayer barrier of raw montmorillonite is relatively low, mainly composed of van der Waals forces, weak interactions between ions, and weak hydrogen bonds of water molecules. Under applied load, the hydrated layer is compressed, reducing the binding energy of ion-water clusters. Slippage, dislocation, or interlayer shear easily occurs between the layers, making it difficult for stress to be effectively transferred between crystal layers, resulting in significant local deformation and thus affecting the reduced modulus only. E r The maximum indentation depth was 3.541 GPa (Young's modulus E was 3.092 GPa). After treatment with a 12 J / cm² picosecond laser, the load-displacement curve showed a significant decrease in maximum indentation depth, while the unloading stiffness (S) significantly increased, resulting in a decrease in the reduced modulus. E r The thermal conductivity was increased to 46.813 GPa (Young's modulus E was 42.481 GPa). This was mainly due to the massive escape of adsorbed water from the interlayer caused by the instantaneous high-energy deposition of picosecond lasers, which prompted the re-coordination of Ca²⁺ ions towards the basal plane, forming translayer anchoring and new ionic cross-linking networks, thus inhibiting interlayer slip. At the same time, the shrinkage of interlayer spacing and the reorganization of interlayer barriers, accompanied by local reconstruction of the framework, promoted the formation of local interlayer collapse and local dense domains. These structural changes reduced plastic dissipation and improved elastic response.

[0045] This application proposes a novel system and method for precisely controlling the Young's modulus of montmorillonite without additives and with spatial selectivity, utilizing ultrashort pulse lasers. The proposed system and method leverage the high-energy photon excitation and non-equilibrium energy deposition characteristics of ultrashort pulse lasers to controllably modulate the interlayer structure and local coordination environment of montmorillonite under low thermal perturbation conditions, achieving programmable adjustment of the Young's modulus. This technology requires no external additives and allows for differentiated modulus design in different regions by adjusting laser parameters, thus providing scalable key support for the application of montmorillonite in ceramic nanoreinforcements, electrochemical energy storage materials, and other scenarios.

[0046] Finally, it should be noted that the various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems or apparatus disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and relevant parts can be referred to the method section.

[0047] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A method for partitioned programmable control of Young's modulus of montmorillonite, characterized in that, Includes the following steps: S1, the pulsed laser emitted by the picosecond pulsed laser (1) passes through the beam expander (2), spatial light modulator (3), sampling mirror (4), first reflector (5), second reflector (6), third reflector (7) and scanning galvanometer (8) in sequence to irradiate montmorillonite (9). The montmorillonite (9) is set above the platform (10). The two beams of light split off by the sampling mirror (4) are collected and recorded by the energy meter (13) and the beam quality analyzer (14) respectively, so as to monitor the energy and spot size of the main optical path in real time. S2, the laser energy incident on the montmorillonite (9) is controlled by a computer control system (15). E in Adjustments were made to perform partitioned matrix pulsed laser scanning of the montmorillonite (9) with different energies, and the laser energy density irradiated onto the montmorillonite (9) was obtained based on the spot area A irradiated onto the montmorillonite (9). F Laser energy density F = E in / A ; S3, control the laser parameters of the picosecond pulse laser so that the total energy inside the montmorillonite (9) satisfies the following relationship: in, F It is energy density. t p Pulse width, It is the laser spot radius. t 0 The peak position of the first laser pulse, R a It is the material's reflectivity. , It is the penetration depth. E It is the Young's modulus of the material. v It is Poisson's ratio. π Pi G Electron-lattice coupling coefficient, t Time variable, c The speed of light in a vacuum x and y Let be the coordinate components of the target point in the laser's plane of action relative to the center of the laser spot in two orthogonal directions. x direction and y The directions are perpendicular to each other and lie within the plane of laser action. Coefficient of thermal expansion; S4. The scanning galvanometer (8) is controlled by the computer control system (15) to perform a partitioned matrix scan on the montmorillonite (9); the temperature of different regions of the montmorillonite (9) is monitored in real time by the spot temperature analyzer (12) to prevent the laser energy from being too high during the irradiation of the montmorillonite, which could cause irreversible damage to the crystal structure.

2. The method for partitioned programmable control of Young's modulus of montmorillonite according to claim 1, characterized in that, Also includes: The Young's modulus of the montmorillonite (9) after picosecond pulsed laser scanning was measured using a synchronous nanoindenter (11).

3. The method for partitioned programmable control of Young's modulus of montmorillonite according to claim 1, characterized in that, The picosecond pulse laser has a pulse width of 10-15 ps.

4. The method for partitioned programmable control of Young's modulus of montmorillonite according to claim 1, characterized in that, The incident laser spot is adjusted to a Gaussian spot with a spatial Gaussian distribution by the spatial light modulator (3).

5. The method for partitioned programmable control of Young's modulus of montmorillonite according to claim 1, characterized in that, The picosecond pulsed laser (1) emits lasers with wavelengths of 355nm, 532nm and 1064nm, a repetition frequency of 50kHz to 400kHz and a scanning speed of 100mm / s to 800mm / s.

6. The method for partitioned programmable control of Young's modulus of montmorillonite according to claim 1, characterized in that, The computer control system (15) controls the scanning mirror (8) to scan different regions of the montmorillonite (9) along a preset moving trajectory.

7. The method for partitioned programmable control of Young's modulus of montmorillonite according to claim 6, characterized in that, The computer control system (15) controls the scanning galvanometer (8) to irradiate each region with the same energy, or to perform laser scanning with different energy according to the preset target region.

8. The method for partitioned programmable control of Young's modulus of montmorillonite according to claim 6, characterized in that, The preset movement trajectory is at least one of the following: cross scan, back-shaped scan, or zigzag scan.

9. The method for partitioned programmable control of Young's modulus of montmorillonite according to claim 1, characterized in that, The first reflector (5), the second reflector (6), and the third reflector (7) are 45-degree reflectors.

10. The method for partitioned programmable control of Young's modulus of montmorillonite according to claim 1, characterized in that, After picosecond laser scanning, the Young's modulus of the montmorillonite (9) increased from a maximum of 3.092 GPa to 42.481 GPa.

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