Manufacturing method of magnetic resonance enhanced metamaterial

Abstract

The invention relates to a manufacturing method of a magnetic resonance enhanced metamaterial. The manufacturing method comprises the following steps: providing a prefabricated metamaterial unit array comprising a plurality of prefabricated unit structures; each prefabricated unit structure comprises a three-dimensional runner structure; filling the three-dimensional flow channel structure with liquid metal to obtain a plurality of semi-finished metamaterials; and processing each semi-finished metamaterial to obtain the magnetic resonance enhanced metamaterial. By using the prefabricated three-dimensional flow channel structure and filling the liquid metal, the electromagnetic performance of the metamaterial can be effectively improved. By adopting the liquid metal filling mode, the manufacturing process of the metamaterial can be simplified, and compared with a traditional process, multiple processing and assembling links are reduced, so that the production efficiency is improved, the processing precision and consistency are ensured, and the manufacturing cost is reduced. And the semi-finished metamaterial is processed, so that the stability and the reliability of the liquid metal in the three-dimensional flow channel structure are ensured. The liquid metal can be prevented from leaking through sealing treatment, and stable performance of the metamaterial in the long-term use process is guaranteed.

Description

Technical Field

[0001] The present application relates to the technical field of magnetic resonance imaging, and in particular to a method for manufacturing a magnetic resonance enhanced metamaterial. Background Art

[0002] MRI (Magnetic Resonance Imaging) technology is widely used in clinical medicine. Its advantages are non-invasiveness, no ionizing radiation, high tissue contrast, and multi-parameter imaging capabilities, so it has attracted widespread attention. In MRI systems, signal-to-noise ratio (SNR) is a key factor in determining image quality, which directly affects image resolution, imaging efficiency, and diagnostic accuracy. Therefore, improving the signal-to-noise ratio to enhance MRI imaging performance has always been an important research direction in this field.

[0003] In recent years, electromagnetic metamaterials have shown significant potential in improving the signal-to-noise ratio of MRI systems. Metamaterials can interact specifically with the radio frequency magnetic field of an MRI system, and by shaping, focusing, and enhancing the radio frequency magnetic field, they can improve the signal-to-noise ratio of a local area without changing the hardware configuration of the existing MRI equipment. They are usually placed in the imaging area of ​​the subject as additional hardware to optimize the radio frequency field distribution and thus improve image quality.

[0004] However, the traditional preparation process of MRI-enhanced metamaterials is difficult to ensure processing accuracy and consistency. Summary of the invention

[0005] Based on this, it is necessary to provide a method for manufacturing magnetic resonance enhanced metamaterials that can improve processing accuracy and consistency in response to the above technical problems.

[0006] In a first aspect, the present application provides a method for manufacturing a magnetic resonance enhanced metamaterial, the method comprising:

[0007] Providing a prefabricated metamaterial unit array; the prefabricated metamaterial unit array comprises a plurality of prefabricated unit structures, each prefabricated unit structure comprises a three-dimensional flow channel structure;

[0008] Filling each three-dimensional flow channel structure with liquid metal to obtain a plurality of semi-finished metamaterials;

[0009] Each semi-finished metamaterial is processed to obtain a magnetic resonance enhanced metamaterial.

[0010] In one embodiment, the above-mentioned three-dimensional flow channel structures are filled with liquid metal to obtain a plurality of semi-finished metamaterials, including:

[0011] Resin removal and curing treatment are performed on each three-dimensional flow channel structure;

[0012] The liquid metal is injected into each three-dimensional flow channel structure using a first syringe to obtain a semi-finished metamaterial.

[0013] In one embodiment, the resin removal and curing process of each three-dimensional flow channel structure includes:

[0014] Using a second syringe, each three-dimensional flow channel structure is injected with anhydrous ethanol; the anhydrous ethanol is used to remove the residual resin in the three-dimensional flow channel structure;

[0015] Each three-dimensional flow channel structure is subjected to light curing and heat curing treatment.

[0016] In one embodiment, the above-mentioned processing of each semi-finished metamaterial to obtain a magnetic resonance enhanced metamaterial includes:

[0017] The semi-finished metamaterials are processed by using preset materials to obtain magnetic resonance enhanced metamaterials; the processing includes one of a silicone sealing process and a circuit connection process.

[0018] In one embodiment, the preset material includes silica gel, and the semi-finished metamaterials are processed with the preset material to obtain the magnetic resonance enhanced metamaterial, including:

[0019] Silicone is injected into the flow channel openings of each semi-finished metamaterial for silicone sealing to obtain a magnetic resonance enhanced metamaterial.

[0020] In one embodiment, the preset material includes a metal wire, and each semi-finished metamaterial is processed with the preset material to obtain a magnetic resonance enhanced metamaterial, including:

[0021] Metal wires are inserted into the flow channel openings of each semi-finished metamaterial for circuit connection processing to obtain a magnetic resonance enhanced metamaterial.

[0022] In one embodiment, the preparation process of the three-dimensional flow channel structure includes:

[0023] Place liquid resin in the resin tank;

[0024] The liquid resin is photocured based on a preset pattern to obtain a three-dimensional flow channel structure.

[0025] In one of the embodiments, there is a corresponding relationship between the number of turns of the three-dimensional flow channel structure and the static magnetic field strength of magnetic resonance imaging.

[0026] In one embodiment, the static magnetic field strength of the magnetic resonance imaging includes low field, high field and ultra-high field, and the method further includes:

[0027] The resonant response measurement and processing of the magnetic resonance enhanced metamaterial are carried out under the conditions of low-field magnetic resonance, high-field magnetic resonance and ultra-high-field magnetic resonance, respectively, to obtain the measurement results, and the number of turns or structure of the three-dimensional flow channel is adjusted according to the measurement results to process the magnetic resonance enhanced metamaterial under different magnetic resonance field strengths.

[0028] In one embodiment, the method further comprises:

[0029] The radio frequency magnetic field enhancement multiple is simulated on the magnetic resonance enhanced metamaterial to obtain simulation results; the simulation results include a two-dimensional distribution diagram and a one-dimensional line diagram of the radio frequency magnetic field enhancement multiple.

[0030] The manufacturing method of the above-mentioned magnetic resonance enhanced metamaterial is provided by providing a prefabricated metamaterial unit array including a plurality of prefabricated unit structures; each prefabricated unit structure includes a three-dimensional flow channel structure; the three-dimensional flow channel structure is filled with liquid metal to obtain a plurality of semi-finished metamaterials; each semi-finished metamaterial is processed to obtain a magnetic resonance enhanced metamaterial. The present application can effectively improve the electromagnetic properties of the metamaterial by using a prefabricated three-dimensional flow channel structure and filling it with liquid metal. The use of liquid metal filling can simplify the manufacturing process of the metamaterial, and compared with the traditional process, it reduces multiple processing and assembly links, thereby improving production efficiency, ensuring processing accuracy and consistency, and reducing manufacturing costs. The semi-finished metamaterial is processed to ensure the stability and reliability of the liquid metal in the three-dimensional flow channel structure. The sealing treatment can prevent the leakage of liquid metal and ensure the stable performance of the metamaterial during long-term use. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a schematic flow chart of a method for manufacturing a magnetic resonance enhanced metamaterial in one embodiment;

[0032] Figure 2 An exemplary diagram of a metamaterial unit array obtained by processing in one embodiment;

[0033] Figure 3 is a front schematic diagram of a prefabricated unit structure in one embodiment;

[0034] Figure 4 is a cross-sectional schematic diagram of a prefabricated unit structure in one embodiment;

[0035] Figure 5 A schematic diagram of a process for obtaining a semi-finished metamaterial in one embodiment;

[0036] Figure 6 A schematic diagram of a process flow of resin removal and curing treatment in one embodiment;

[0037] Figure 7 A schematic diagram of a process for preparing a three-dimensional flow channel structure in one embodiment;

[0038] Figure 8 A resonance characteristic simulation diagram in one embodiment;

[0039] Fig. 9 is a measurement result of a resonance response experiment in an embodiment;

[0040] Fig.10a One of the simulation results of a magnetic resonance enhanced metamaterial in one embodiment;

[0041] Fig.10b This is the second simulation result of the magnetic resonance enhanced metamaterial in one embodiment;

[0042] Fig.10c The third simulation result of the magnetic resonance enhanced metamaterial in one embodiment;

[0043] Fig.11 FIG. 1 is an overall process flow chart for making a metamaterial unit mold in an embodiment. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0045] First of all, before specifically introducing the technical solution of the embodiments of the present application, the technical background based on the embodiments of the present application is introduced.

[0046] Magnetic resonance imaging (MRI) technology is widely used in clinical medicine. Its advantages are non-invasiveness, no ionizing radiation, high tissue contrast, and multi-parameter imaging capabilities, so it has attracted widespread attention. In MRI systems, signal-to-noise ratio (SNR) is a key factor in determining image quality, which directly affects image resolution, imaging efficiency, and diagnostic accuracy. Therefore, improving the signal-to-noise ratio to enhance MRI imaging performance has always been an important research direction in this field.

[0047] In recent years, electromagnetic metamaterials have shown significant potential in improving the signal-to-noise ratio of MRI systems. Metamaterials are artificially designed spatial periodic resonant structures that can produce specific interactions with the radio frequency magnetic field of the MRI system. By shaping, focusing and enhancing the radio frequency magnetic field, the signal-to-noise ratio of the local area can be improved without changing the hardware configuration of the existing MRI equipment. Usually, this type of metamaterial is placed in the imaging area of ​​the subject as additional hardware to optimize the radio frequency field distribution and thus improve image quality.

[0048] However, as an artificial material, the performance of metamaterials is highly dependent on structural design. The traditional preparation processes of MRI-enhanced metamaterials mainly include copper wire winding, copper foil cutting and printed circuit board (PCB) processing. These traditional processes face multiple challenges when processing complex or irregular three-dimensional structures, including difficulty in ensuring processing accuracy and consistency, and requiring more time or manpower. These limitations directly limit the structural design flexibility and performance optimization potential of metamaterials in MRI applications.

[0049] Based on this, the present application provides a method for manufacturing a magnetic resonance enhanced metamaterial, aiming to solve the above technical problems.

[0050] In an exemplary embodiment, Figure 1 As shown, the embodiment of the present application provides a method for manufacturing a magnetic resonance enhanced metamaterial, comprising the following steps:

[0051] S101, providing a prefabricated metamaterial unit array.

[0052] Among them, Figure 2 As shown, the prefabricated metamaterial unit array includes a plurality of prefabricated unit structures 1010, such as Figure 3 Shown and Figure 4 As shown, each prefabricated unit structure 1010 includes a three-dimensional flow channel structure 1011. The three-dimensional flow channel structure 1011 is filled with liquid metal 1012.

[0053] In the embodiment of the present application, the prefabricated metamaterial unit array is an orderly arrangement of multiple prefabricated unit structures. Each prefabricated unit structure includes a three-dimensional flow channel structure. The three-dimensional flow channel structure here is a channel with a specific shape and size for accommodating liquid metal. The three-dimensional flow channel structure can be made by a precision 3D printing method. By precisely controlling the size and shape of the flow channel, the distribution of the liquid metal can be precisely regulated, thereby optimizing the electromagnetic properties of the metamaterial.

[0054] Furthermore, the shape, size and arrangement of the prefabricated unit structure are designed according to the requirements of magnetic resonance imaging. Computer-aided design software can be used for design, and the prefabricated metamaterial unit mold can be manufactured by micromachining technology.

[0055] S102, filling the three-dimensional flow channel structure with liquid metal to obtain a plurality of semi-finished metamaterials.

[0056] Among them, liquid metal is a metal or alloy that is liquid at room temperature and has good conductivity and fluidity.

[0057] In the embodiment of the present application, a suitable liquid metal is selected and filled into the three-dimensional flow channel structure of the prefabricated unit structure by capillary action or pressure injection. The filling process needs to ensure that the liquid metal completely fills the flow channel and there are no bubbles or impurities. The filled prefabricated unit structure becomes a semi-finished metamaterial. This liquid metal structure generates a specific induced magnetic field under electromagnetic excitation, which provides a basis for magnetic resonance enhancement.

[0058] Furthermore, according to the requirements of magnetic resonance enhancement, a suitable liquid metal is selected. Considering factors such as conductivity, fluidity, and stability, the prefabricated metamaterial unit mold is placed in a vacuum environment to remove air and impurities in the flow channel. Then, the liquid metal is filled into the three-dimensional flow channel structure using methods such as capillary action or pressure injection. The filling process needs to be carried out slowly to ensure that the liquid metal completely fills the flow channel and no bubbles are generated. The filling process can be monitored using X-rays, CT, or other detection equipment to ensure the filling quality.

[0059] S103, processing each semi-finished metamaterial to obtain a magnetic resonance enhanced metamaterial.

[0060] Among them, processing is to ensure the stability and reliability of liquid metal in metamaterials. Packaging materials such as polymers and ceramics can be used to seal semi-finished metamaterials. The packaging materials need to have good insulation, mechanical strength and chemical stability to prevent liquid metal leakage and oxidation. Processing can be done by injection molding, spraying, deposition and other methods, selected according to specific material and process requirements. The final magnetic resonance enhanced metamaterial has good electromagnetic properties and stability, can effectively enhance magnetic resonance signals and improve imaging quality.

[0061] Further, a suitable encapsulation material is selected, such as a polymer or ceramic. The encapsulation material is heated to a molten state, and then covered on the semi-finished metamaterial by injection molding, spraying or deposition to form a sealed shell. The encapsulation material needs to have good insulation, mechanical strength and chemical stability to prevent liquid metal leakage and oxidation. The encapsulated metamaterial can be further processed and treated, such as grinding, polishing, etc., to improve its surface quality and appearance.

[0062] The manufacturing method of the above-mentioned magnetic resonance enhanced metamaterial is provided by providing a prefabricated metamaterial unit array including a plurality of prefabricated unit structures; each prefabricated unit structure includes a three-dimensional flow channel structure; the three-dimensional flow channel structure is filled with liquid metal to obtain a plurality of semi-finished metamaterials; each semi-finished metamaterial is processed to obtain a magnetic resonance enhanced metamaterial. The present application can effectively improve the electromagnetic properties of the metamaterial by using a prefabricated three-dimensional flow channel structure and filling it with liquid metal. The use of liquid metal filling can simplify the manufacturing process of the metamaterial, and compared with the traditional process, it reduces multiple processing and assembly links, thereby improving production efficiency, ensuring processing accuracy and consistency, and reducing manufacturing costs. The semi-finished metamaterial is processed to ensure the stability and reliability of the liquid metal in the three-dimensional flow channel structure. The sealing treatment can prevent the leakage of liquid metal and ensure the stable performance of the metamaterial during long-term use.

[0063] In an exemplary embodiment, based on the above embodiment, see Figure 5 The embodiment of the present application relates to a process of performing metal filling treatment on each prefabricated unit structure to obtain a semi-finished metamaterial, including the following steps:

[0064] S201, performing resin removal and curing treatment on the three-dimensional flow channel structure.

[0065] Three-dimensional flow channel structure: It is a key part of the prefabricated unit structure. It is a channel with a specific shape and size to contain liquid metal to achieve specific electromagnetic properties. It is usually manufactured using micromachining technology, such as photolithography, etching and other methods to form three-dimensional flow channels on the substrate material. These flow channels can be complex geometric shapes to meet different magnetic resonance enhancement requirements.

[0066] Resin removal: In the process of manufacturing prefabricated unit structures, resin materials may be used for auxiliary processing or support. Before metal filling, these resins need to be cleaned to ensure that the liquid metal can smoothly fill the flow channel and is not affected by resin impurities. Chemical solvent cleaning, high temperature baking and other methods can be used to remove the resin.

[0067] Curing: After the resin is removed, the three-dimensional flow channel structure is cured to improve its mechanical strength and stability. Curing can be done by heating, ultraviolet radiation, etc., making the material of the flow channel structure stronger and able to withstand subsequent metal filling and processing.

[0068] Specifically, if the heating curing method is adopted, the prefabricated unit structure can be placed in an oven and heated at a certain temperature for a period of time. The heating temperature and time are determined according to the material of the flow channel structure and the curing requirements. For ultraviolet curing materials, ultraviolet irradiation equipment can be used to irradiate the prefabricated unit structure to quickly cure the material.

[0069] S202, using a first syringe to inject liquid metal into the three-dimensional flow channel structure to obtain a semi-finished metamaterial.

[0070] First syringe: is a tool specially used for precise injection of liquid metal. It usually has a high-precision injection control mechanism that can accurately control the amount and speed of liquid metal injected. The needle of the first syringe needs to match the inlet of the three-dimensional flow channel structure to ensure that the liquid metal can be smoothly injected into the flow channel without leakage.

[0071] Liquid metal: In this embodiment, liquid metal is a metal or alloy that is liquid at room temperature and has good conductivity and fluidity. Liquid metals such as gallium-indium alloys are selected to fill the three-dimensional flow channel structure to achieve specific electromagnetic properties of magnetic resonance enhanced metamaterials. When injecting liquid metal, it needs to be done slowly and evenly to avoid bubbles or uneven filling.

[0072] Specifically, select a suitable first syringe and ensure that its needle matches the inlet size of the three-dimensional flow channel structure. Suck the liquid metal into the first syringe and insert the needle into the inlet of the three-dimensional flow channel structure. Slowly push the piston of the syringe to evenly inject the liquid metal into the flow channel. Bubbles and uneven filling can be avoided by controlling the injection speed and pressure. Observe the filling of the liquid metal to ensure that the flow channel is completely filled with liquid metal.

[0073] The embodiment of the present application ensures the cleanliness and stability of the three-dimensional flow channel structure through resin removal and curing treatment, providing a good foundation for uniform filling of liquid metal. The first syringe is used for liquid metal injection, which can achieve precise control and uniform filling, and improve the quality and performance stability of the semi-finished metamaterial.

[0074] In an exemplary embodiment, based on the above embodiment, see Figure 6 The embodiment of the present application relates to a process of removing resin and curing a three-dimensional flow channel structure, comprising the following steps:

[0075] S301, using a second syringe to inject anhydrous ethanol into the three-dimensional flow channel structure.

[0076] Among them, the second syringe: Similar to the first syringe in the previous embodiment, the second syringe is also a tool for accurately injecting liquid. It can be selected in different specifications and models according to different processing requirements. In the embodiment of the present application, the second syringe is used to inject anhydrous ethanol to remove residual resin in the three-dimensional flow channel structure.

[0077] Anhydrous ethanol: A commonly used organic solvent with good solubility and volatility. In this embodiment, anhydrous ethanol is used to dissolve and remove residual resin in the three-dimensional flow channel structure. Since anhydrous ethanol is easily volatile at room temperature, it can be quickly removed after treatment without adversely affecting subsequent process steps.

[0078] During the manufacturing process of the prefabricated unit structure, some resin may remain in the three-dimensional flow channel structure. This residual resin will affect the filling effect of the liquid metal and the performance of the metamaterial, so it needs to be removed. The residual resin may come from auxiliary materials in the manufacturing process or resin components that are not completely removed.

[0079] In an embodiment of the present application, a suitable second syringe is selected to ensure that its needle can be smoothly inserted into the entrance of the three-dimensional flow channel structure. Anhydrous ethanol is sucked into the second syringe, and the needle is inserted into the entrance of the three-dimensional flow channel structure. The piston of the syringe is slowly pushed to inject the anhydrous ethanol into the flow channel. During the injection process, the prefabricated unit structure can be gently shaken to ensure that the anhydrous ethanol can fully contact the residual resin and dissolve it. Wait for a while to allow the anhydrous ethanol to fully dissolve the residual resin. Then, the prefabricated unit structure is tilted or inverted to allow the anhydrous ethanol dissolved with the residual resin to flow out of the flow channel. The injection and outflow process can be repeated until the residual resin in the flow channel is completely removed.

[0080] S302, performing photocuring and thermal curing treatment on the three-dimensional flow channel structure.

[0081] Among them, photocuring is a method of using ultraviolet light or other specific wavelengths of light to trigger a chemical reaction to quickly cure a material. In this embodiment, photocuring can be used to initially cure the three-dimensional flow channel structure to improve its mechanical strength and stability. Photocuring usually requires the use of specific photocuring equipment and photoinitiators to ensure the curing effect.

[0082] Thermal curing: A method of curing by heating the material to cause a chemical reaction. Thermal curing can further improve the degree of curing of the three-dimensional flow channel structure and enhance its mechanical properties and durability. The temperature and time of thermal curing need to be adjusted according to the characteristics of the material and the curing requirements.

[0083] In an embodiment of the present application, the prefabricated unit structure treated with anhydrous ethanol is placed in a light curing device. The light curing device generally includes a UV light source, a reflector, a sample stage, and other parts. The UV light source is turned on to irradiate the prefabricated unit structure. The irradiation time and intensity need to be adjusted according to the characteristics of the material and the curing requirements. During the irradiation process, the position of the prefabricated unit structure can be appropriately adjusted to ensure that the UV light can evenly irradiate all parts of the flow channel structure.

[0084] The prefabricated unit structure that has been treated with light curing is placed in an oven for heat curing. The temperature and time of the oven need to be adjusted according to the characteristics of the material and the curing requirements. Generally speaking, the temperature of heat curing will be higher than that of light curing to ensure that the material can be fully cured. During the heat curing process, the degree of curing of the prefabricated unit structure can be checked regularly to determine whether it is necessary to extend the curing time or adjust the curing temperature.

[0085] The embodiment of the present application adopts anhydrous ethanol injection treatment to effectively remove the residual resin in the three-dimensional flow channel structure, improve the filling effect of liquid metal and the performance of metamaterials. Photocuring and thermal curing treatment can further improve the curing degree of the three-dimensional flow channel structure, enhance its mechanical strength and durability, and thus improve the stability and reliability of the metamaterial.

[0086] In an exemplary embodiment, based on the above embodiments, the embodiments of the present application involve a process of processing each semi-finished metamaterial to obtain a magnetic resonance enhanced metamaterial, specifically including: using a preset material to process each semi-finished metamaterial to obtain a magnetic resonance enhanced metamaterial.

[0087] Among them, the processing includes one of a silicone sealing process and a circuit connection process.

[0088] Preset materials refer to specific materials specially used to seal semi-finished metamaterials. These materials should have good sealing, mechanical strength and chemical stability to ensure that they can effectively prevent liquid metal leakage in a magnetic resonance environment without affecting the electromagnetic properties of the metamaterial. For example, polymers, ceramic materials, metal alloys, etc. can be selected as preset materials. Different preset materials have different characteristics and application ranges, and can be selected according to specific needs.

[0089] Processing process: First, the semi-finished metamaterial is cleaned and pre-treated to remove impurities and contaminants on the surface. Then, according to the characteristics of the preset material and the processing requirements, a suitable closed processing method is selected. Common closed processing methods include injection molding, spraying, deposition, welding, etc. For example, if a high molecular polymer is selected as the preset material, the polymer can be injected into the vicinity of the semi-finished metamaterial by injection molding to form a sealed shell. If a ceramic material is selected, a layer of ceramic coating can be formed on the surface of the semi-finished metamaterial by spraying or deposition. If a metal alloy is selected, a metal alloy sheet or wire can be welded to the flow channel opening of the semi-finished metamaterial by welding. During the closed processing, processing parameters such as temperature, pressure, speed, etc. need to be strictly controlled to ensure that the preset material can evenly cover the surface of the semi-finished metamaterial to form a complete and sealed structure.

[0090] Select a preset material:

[0091] According to the performance requirements and use environment of the magnetic resonance enhanced metamaterial, select the appropriate preset material. For example, if the metamaterial needs to have good flexibility and impact resistance, you can choose a polymer such as polyurethane, silicone rubber, etc. If the metamaterial needs to have high mechanical strength and high temperature resistance, you can choose a ceramic material such as aluminum oxide, zirconium oxide, etc. If the metamaterial needs to have good conductivity and electromagnetic shielding performance, you can choose a metal alloy such as copper alloy, aluminum alloy, etc.

[0092] Pre-processing semi-finished metamaterials:

[0093] Clean the semi-finished metamaterial to remove impurities such as oil, dust, etc. on the surface. Cleaning can be performed by using solvent cleaning or other methods.

[0094] The semi-finished metamaterial is subjected to surface treatment to improve the bonding strength between the preset material and the semi-finished metamaterial. For example, the surface of the semi-finished metamaterial can be activated by plasma treatment, chemical etching, etc.

[0095] Select the enclosed processing process: According to the characteristics of the preset material and the processing requirements, select the appropriate enclosed processing method. For example, if a polymer is selected as the preset material, the injection molding method can be used. After the polymer particles are heated and melted, the molten polymer is injected into the mold through an injection molding machine. The shape of the mold matches the shape of the semi-finished metamaterial. During the injection molding process, parameters such as injection pressure, temperature and speed need to be controlled to ensure that the polymer can be evenly filled around the semi-finished metamaterial to form a sealed shell.

[0096] If ceramic material is selected as the preset material, spraying or deposition methods can be used. The spraying method is to mix ceramic powder with a binder, and then spray the mixed powder on the surface of the semi-finished metamaterial through a spray gun to form a ceramic coating. The deposition method is to form a ceramic film on the surface of the semi-finished metamaterial by physical vapor deposition or chemical vapor deposition of ceramic materials. During the spraying or deposition process, it is necessary to control the spraying or deposition parameters, such as powder particle size, spraying distance, deposition temperature, etc., to ensure the quality and performance of the ceramic coating or film.

[0097] The embodiment of the present application uses preset materials to process the semi-finished metamaterial, which can effectively prevent liquid metal leakage and improve the stability and reliability of the metamaterial. Different preset materials can give the metamaterial different performance and characteristics to meet different application requirements.

[0098] In an exemplary embodiment, based on the above embodiments, the preset materials of the embodiments of the present application include silicone, and the preset materials are used to process each semi-finished metamaterial to obtain a magnetic resonance enhanced metamaterial, specifically including: injecting silicone into the flow channel openings of each semi-finished metamaterial to perform silicone sealing treatment to obtain a magnetic resonance enhanced metamaterial.

[0099] Silicone is a polymer elastic material with good flexibility, insulation, high temperature resistance and corrosion resistance. In this embodiment, a suitable silicone material is selected, which should have good fluidity and curing properties so that it can be smoothly injected into the flow channel opening of the semi-finished metamaterial and cured under certain conditions to form a sealing structure.

[0100] Processing process: First, prepare the semi-finished metamaterial that needs to be closed and ensure that its flow channel opening is clean and free of impurities. Then, select a suitable silicone injection device, such as a syringe, a glue dispenser, etc. Load the silicone material into the injection device and adjust the injection parameters, such as injection pressure, speed, etc. Next, aim the needle of the injection device at the flow channel opening of the semi-finished metamaterial and slowly inject the silicone into the flow channel opening. During the injection process, pay attention to the filling of the silicone to ensure that the silicone can fully fill the flow channel opening and there are no bubbles and gaps. When the silicone completely fills the flow channel opening, place the semi-finished metamaterial in an appropriate environment for curing according to the curing characteristics of the silicone. The curing time and conditions can be adjusted according to the type of silicone and the instructions for use. After curing, the magnetic resonance enhanced metamaterial is obtained.

[0101] In the embodiment of the present application, the silicone has good flexibility and sealing properties, which can effectively prevent the leakage of liquid metal and improve the stability and reliability of the metamaterial. The injection process of the silicone is simple and easy, and can be operated by a syringe, a glue filling machine and other equipment, which is suitable for large-scale production and application. The curing time and conditions of the silicone can be adjusted as needed to meet different production process requirements. The magnetic resonance enhanced metamaterial after silicone processing has good mechanical strength and high temperature resistance, and can work stably for a long time in a magnetic resonance environment.

[0102] In an exemplary embodiment, based on the above embodiments, the preset materials of the embodiments of the present application include metal wires, and the preset materials are used to process each semi-finished metamaterial to obtain a magnetic resonance enhanced metamaterial, specifically including: inserting the metal wires into the flow channel openings of each semi-finished metamaterial for circuit connection processing to obtain a magnetic resonance enhanced metamaterial.

[0103] Among them, metal wire: The metal wire is usually made of metal materials with good electrical conductivity such as copper, aluminum, and silver. In this embodiment, a suitable metal wire is selected, and its diameter should match the size of the flow channel opening of the semi-finished metamaterial to ensure that it can be tightly inserted into the flow channel opening and form a good seal. The metal wire should also have a certain degree of flexibility and mechanical strength so that it is not easy to break during the insertion process.

[0104] Processing process: First, prepare the semi-finished metamaterial that needs to be closed and ensure that its flow channel opening is clean and free of impurities. Then, select a suitable metal wire and cut or bend it according to the size and shape of the flow channel opening so that it can be smoothly inserted into the flow channel opening. Next, use a tool to carefully insert the metal wire into the flow channel opening of the semi-finished metamaterial, ensuring that the insertion depth is appropriate and the metal wire is in close contact with the inner wall of the flow channel. After inserting the metal wire, further fixing and sealing treatment can be performed as needed, such as using glue, welding, etc. to fix the metal wire to the semi-finished metamaterial to prevent the metal wire from falling off. Finally, a magnetic resonance enhanced metamaterial is obtained.

[0105] In the embodiment of the present application, the opening of the flow channel is sealed by silicone, or copper wires are inserted into the inlet and outlet of the flow channel to connect the liquid metal to the external copper structure or copper circuit, thereby completing the final processing of the metamaterial unit.

[0106] In an exemplary embodiment, based on the above embodiment, see Figure 7 The preparation process of the three-dimensional flow channel structure of the embodiment of the present application includes the following steps:

[0107] S401, placing liquid resin in a resin tank.

[0108] Liquid resin: Liquid resin is a material with specific chemical composition and physical properties, which can be cured to form a solid structure under specific conditions. In this embodiment, the selected liquid resin should have good fluidity, light curing performance and mechanical strength. For example, a light curing resin can be selected, which can be quickly cured under ultraviolet light or light of a specific wavelength.

[0109] Resin tank: A container for holding liquid resin. Its material should have good chemical stability and not react with the liquid resin. The shape and size of the resin tank can be designed according to the three-dimensional flow channel structure to be prepared.

[0110] In the embodiments of the present application, a suitable liquid resin is selected, and factors such as the fluidity, curing speed, and mechanical strength of the resin are considered according to the performance requirements of the desired three-dimensional flow channel structure. Some preliminary tests can be performed to determine the best type and parameters of the resin. Prepare a resin tank and select a suitable material, such as glass, stainless steel, etc., to ensure that the resin tank is clean and dry. Determine the size and shape of the resin tank according to the size of the three-dimensional flow channel structure to be prepared. Slowly inject the liquid resin into the resin tank to avoid bubbles and impurities. Tools such as syringes and funnels can be used for injection to ensure that the liquid level of the resin is appropriate for photocuring.

[0111] S402, performing photocuring on the liquid resin based on the preset pattern to obtain a three-dimensional flow channel structure.

[0112] The preset pattern is a specific graphic designed according to the required three-dimensional flow channel structure. It can be designed by computer-aided design software and converted into a format that can be recognized by the light-curing equipment. The preset pattern should include information such as the shape, size, and connection method of the flow channel.

[0113] Photocuring: Photocuring is the process of irradiating liquid resin with light of a specific wavelength to cause a chemical reaction and solidification. In this embodiment, a photocuring device, such as an ultraviolet lithography machine, a digital light processing device, etc., can be used to photocuring the liquid resin. The photocuring device emits light of a specific wavelength according to a preset pattern to irradiate the liquid resin, so that the resin in the irradiated area is quickly cured, while the unirradiated area remains liquid. By performing photocuring point by point or layer by layer, a three-dimensional flow channel structure can be gradually constructed.

[0114] In an embodiment of the present application, a preset pattern is imported into a photocuring device, and settings and adjustments are performed according to the operating instructions of the device. Ensure that the light source intensity, exposure time, resolution and other parameters of the photocuring device meet the requirements. Start the photocuring device and perform photocuring on the liquid resin. According to the preset pattern, the photocuring device irradiates the liquid resin point by point or layer by layer to cure the resin in the irradiated area. The accuracy and quality of the three-dimensional flow channel structure can be adjusted by controlling parameters such as the moving speed and number of exposures of the photocuring device. During the photocuring process, pay attention to observe the curing of the resin and adjust the parameters in time to ensure the integrity and accuracy of the three-dimensional flow channel structure.

[0115] The embodiment of the present application adopts light curing treatment, which can realize the preparation of high-precision three-dimensional flow channel structure and meet the precision requirements of magnetic resonance enhanced metamaterials for flow channel structure. The light curing treatment speed is fast, which can greatly shorten the preparation time and improve production efficiency.

[0116] In an exemplary embodiment, based on the above embodiments, there is a corresponding relationship between the range of the number of turns of the three-dimensional flow channel structure of the embodiment of the present application and the static magnetic field strength of magnetic resonance imaging.

[0117] like Figure 8 As shown, the process structure design of the metamaterial unit under multiple static magnetic field strengths and the simulation of its resonance characteristics. According to the requirements for the resonant frequency under different static magnetic field strengths, the flow channel design is optimized to match the Larmor frequency of hydrogen nuclei under a specific static magnetic field. On the premise of keeping the overall size of the metamaterial unit unchanged, by adjusting the number of turns of the flow channel, the resonant frequency of the metamaterial can be matched with the Larmor frequency of hydrogen nuclei under given static magnetic field conditions. Specifically, the design features of the metamaterial unit include: the main radius of the precision 3D printed flow channel 1011 torus is 15mm, and the tube radius is 1.6mm; the number of circles around the main radius of the liquid metal flow channel is between 2 and 12. This design enables the metamaterial flow channel to cover the Larmor frequency of hydrogen nuclei under different static magnetic field strengths, including the following situations:

[0118] 1) Low-field MRI: The static magnetic field strength ranges from 0.25 to 1.0 Tesla (T), the hydrogen nucleus Larmor frequency ranges from 10.6 to 42.6 megahertz (MHz), and the number of turns of the liquid metal flow channel under the design features of the above-mentioned metamaterial unit is approximately between 9 and 12 turns.

[0119] 2) High-field MRI: The static magnetic field strength ranges from 1.0 to 4.0 Tesla (T), the hydrogen nucleus Larmor frequency ranges from 42.6 to 170.4 megahertz (MHz), and the number of turns of the liquid metal flow channel is approximately between 4 and 8 turns under the design features of the above-mentioned metamaterial unit.

[0120] 3) Ultra-high field MRI: The static magnetic field strength is greater than 4.0 Tesla (T), the hydrogen nucleus Larmor frequency is greater than 170.4 megahertz (MHz), and the number of turns of the liquid metal flow channel is approximately between 2 and 3 under the design features of the above-mentioned metamaterial unit.

[0121] The embodiment of the present application can optimize the design of the three-dimensional flow channel structure according to specific application requirements to obtain the best magnetic resonance enhancement effect by determining the corresponding relationship between the number of turns of the three-dimensional flow channel structure and the static magnetic field strength of magnetic resonance imaging.

[0122] In an exemplary embodiment, based on the above embodiments, the static magnetic field strength of the magnetic resonance imaging of the embodiment of the present application includes low field, high field and ultra-high field, and the method of the embodiment of the present application also includes the following steps: performing resonant response measurement processing on the magnetic resonance enhanced metamaterial under the conditions of low field magnetic resonance, high field magnetic resonance and ultra-high field magnetic resonance, respectively, to obtain measurement results, and adjusting the number of turns or structure of the three-dimensional flow channel according to the measurement results to process the magnetic resonance enhanced metamaterial under different magnetic resonance field strengths.

[0123] Measurement results: Fig. 9 As shown, the obtained measurement results include the resonance characteristics of the metamaterial samples under different field strengths. These results can reflect that by adjusting the number of turns or structure of the three-dimensional flow channel, MRI enhanced metamaterials suitable for different MRI field strengths can be processed.

[0124] The embodiment of the present application first prepares a series of metamaterial samples with three-dimensional flow channel structures of different numbers of turns. Prepare a vector network analyzer and a test antenna device, and perform calibration and debugging. Perform computer simulation to simulate the magnetic resonance response of three-dimensional flow channel structures with different numbers of turns under different field strengths. Use a vector network analyzer and a test antenna to test metamaterial samples with different numbers of turns. According to a predetermined measurement plan, measure the resonant response of each sample and record the measurement results.

[0125] In the embodiment of the present application, the measurement results are collated and analyzed, and the relationship curve between the resonance response and the number of turns under different field strengths is plotted. The measurement results and simulation results are compared to find the range of turns with the best magnetic resonance enhancement effect under different field strengths. According to the specific application requirements, the final number of turns of the three-dimensional flow channel structure is determined by comprehensively considering factors such as cost and performance.

[0126] In an exemplary embodiment, based on the above embodiment, the process of the method of the present application specifically includes: performing radio frequency magnetic field enhancement multiple simulation processing on the magnetic resonance enhanced metamaterial to obtain a simulation result; Fig.10a , 10b and 10c. The simulation results include a two-dimensional distribution diagram of the RF magnetic field enhancement factor and a corresponding one-dimensional line diagram along the red line in the two-dimensional diagram. The results show that the RF magnetic field is significantly enhanced by about 20 to 25 times in the region of interest near the metamaterial. This enhancement effect ensures that the metamaterial unit can significantly improve the signal intensity in low-field, high-field, and ultra-high-field MRI applications, thereby optimizing the imaging effect.

[0127] In an exemplary embodiment, based on the above embodiment, the overall process flow chart of making a metamaterial unit mold is as follows: Fig.11 As shown, the method of the embodiment of the present application specifically includes the following steps:

[0128] Step 1: Determine the number of turns of the three-dimensional flow channel structure;

[0129] Step 2: placing liquid resin in a resin tank; performing photocuring on the liquid resin based on a preset pattern to obtain a three-dimensional flow channel structure; providing a prefabricated metamaterial unit mold including the three-dimensional flow channel structure;

[0130] Step 3: using a second syringe, injecting anhydrous ethanol into each three-dimensional flow channel structure; the anhydrous ethanol is used to remove the residual resin in the three-dimensional flow channel structure; performing light curing and heat curing on each three-dimensional flow channel structure;

[0131] Step 4: using a first syringe to inject liquid metal into each three-dimensional flow channel structure to obtain each semi-finished metamaterial;

[0132] Step 5: injecting silica gel into the flow channel openings of each semi-finished metamaterial to perform silica gel sealing treatment to obtain a magnetic resonance enhanced metamaterial; or inserting a metal wire into the flow channel openings of each semi-finished metamaterial to perform circuit connection treatment to obtain a magnetic resonance enhanced metamaterial.

[0133] It should be understood that, although the various steps in the flowcharts involved in the above-mentioned embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above-mentioned embodiments can include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0134] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0135] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for manufacturing a magnetic resonance enhanced metamaterial, characterized in that: The method comprises: Providing a prefabricated metamaterial unit array; the prefabricated metamaterial unit array comprises a plurality of prefabricated unit structures, each of the prefabricated unit structures comprises a three-dimensional flow channel structure; Filling each of the three-dimensional flow channel structures with liquid metal to obtain a plurality of semi-finished metamaterials; Each of the semi-finished metamaterials is processed to obtain a magnetic resonance enhanced metamaterial.

2. The method according to claim 1, characterized in that The three-dimensional flow channel structures are filled with liquid metal to obtain a plurality of semi-finished metamaterials, including: Performing resin removal and curing treatment on each of the three-dimensional flow channel structures; The liquid metal is injected into each of the three-dimensional flow channel structures using a first syringe to obtain each of the semi-finished metamaterials.

3. The method according to claim 2, characterized in that The resin removal and curing treatment of each of the three-dimensional flow channel structures includes: Using a second syringe, injecting anhydrous ethanol into each of the three-dimensional flow channel structures; the anhydrous ethanol is used to remove residual resin in the three-dimensional flow channel structure; Each of the three-dimensional flow channel structures is subjected to light curing and heat curing treatment.

4. The method according to claim 1, characterized in that: The processing of each of the semi-finished metamaterials to obtain a magnetic resonance enhanced metamaterial comprises: The semi-finished metamaterials are processed by using preset materials to obtain magnetic resonance enhanced metamaterials; the processing includes one of a silicone sealing process and a circuit connection process.

5. The method according to claim 4, characterized in that The preset material includes silica gel, and the semi-finished metamaterials are processed by using the preset material to obtain the magnetic resonance enhanced metamaterial, including: The silica gel is injected into the flow channel opening of each of the semi-finished metamaterials to perform silica gel sealing treatment to obtain the magnetic resonance enhanced metamaterial.

6. The method according to claim 4, characterized in that The preset material includes a metal wire, and the semi-finished metamaterials are processed by using the preset material to obtain a magnetic resonance enhanced metamaterial, including: The metal wire is inserted into the flow channel opening of each semi-finished metamaterial to perform circuit connection processing to obtain a magnetic resonance enhanced metamaterial.

7. The method according to claim 2, characterized in that The preparation process of the three-dimensional flow channel structure includes: Place liquid resin in the resin tank; The liquid resin is photocured based on a preset pattern to obtain the three-dimensional flow channel structure.

8. The method according to claim 6, characterized in that There is a corresponding relationship between the range of the number of turns of the three-dimensional flow channel structure and the static magnetic field strength of magnetic resonance imaging.

9. The method according to claim 8, characterized in that The static magnetic field strength of the magnetic resonance imaging includes low field, high field and ultra-high field, and the method further includes: The magnetic resonance enhanced metamaterial is subjected to resonant response measurement under the conditions of the low-field magnetic resonance, the high-field magnetic resonance and the ultra-high-field magnetic resonance to obtain measurement results, and the number of turns or structure of the three-dimensional flow channel is adjusted according to the measurement results to process the magnetic resonance enhanced metamaterial under different magnetic resonance field strengths.

10. The method according to claim 9, characterized in that The method further comprises: The radio frequency magnetic field enhancement multiple simulation processing is performed on the magnetic resonance enhanced metamaterial to obtain a simulation result; the simulation result includes a two-dimensional distribution diagram and a one-dimensional line diagram of the radio frequency magnetic field enhancement multiple.

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