Combined PCM magnetic lens heat storage and shock absorption system and application

Abstract

The application provides a combined PCM magnetic lens heat storage and damping system and application, and comprises the following steps: determining a temperature variation interval of a working state of a magnetic lens heat source; selecting different phase change temperature PCMs as first PCMs, second PCMs and third PCMs according to the temperature variation interval; melting the PCMs into a molten state respectively, and embedding the magnetic lens heat source in the PCMs with the phase change temperature changing from high to low in the radial direction through the mode of immersion and solidification of the magnetic lens heat source in sequence; adjusting the volume ratio between the combined PCMs by evaluating the change of the working temperature of the magnetic lens before and after the action of the combined PCMs; the system introduces a phase change heat transfer mechanism into the structure of the magnetic lens, provides a uniform and temperature-controllable heat dissipation effect for the magnetic lens, and enhances the thermal stability and mechanical stability of the magnetic lens in the mode of filling with multiple layers of PCMs.

Description

Technical Field

[0001] This invention relates to the field of magnetic lens technology, and in particular to a magnetic lens heat storage and vibration damping system and its application using a combined PCM. Background Technology

[0002] Magnetic lenses are the core components of charged particle beams, generating magnetic fields that focus, image, and deflect the particle beam. When a magnetic lens operates, a coil needs to be energized to create a strong localized magnetic field in the gap between the pole pieces, thus controlling the particle beam's trajectory. Due to the thermal effect of the energized coil, the component in a magnetic lens that generates the magnetic field and requires power is referred to as a "heat source" in thermal management. To maintain a constant equipment temperature, conventional magnetic lenses must be cooled with circulating water during operation to ensure heat dissipation. Simultaneously, due to the demagnetizing field, the magnetic charge tends to concentrate in areas of high curvature at the pole pieces, causing a significant temperature rise in the pole piece material. This heating leads to thermal expansion, causing changes in the magnetic lens's mechanical dimensions. If this heat cannot be dissipated in time, it can cause thermal runaway, affecting the lens's focusing and rotation of charged particle beams (such as electron beams and ion beams), and reducing the equipment's accuracy and stability. This phenomenon is more pronounced in strong magnetic lenses operating near saturation with high current.

[0003] Phase change materials (PCMs) are mainly classified into inorganic PCMs, organic PCMs, and composite PCMs based on their material composition. Based on their phase change temperature, they can be further classified into three categories: low-temperature PCMs (<100℃), medium-temperature PCMs (100℃~450℃), and high-temperature PCMs (>450℃).

[0004] Currently, there are still technical problems to be improved in the existing technology regarding the handling of heat loss of magnetic lenses and the application expansion of PCM in the field of phase change heat transfer. These problems mainly manifest as follows: ① The water cooling circulation system of the magnetic lens has uneven heat dissipation and the heat dissipation temperature is uncontrollable; ② There is no fixed connection between the magnetic lens pole piece and the coil, and even a small vibration will affect its focusing and deflection effect; ③ The heat storage adjustability of a single PCM is low and its volume is fixed.

[0005] Therefore, this invention provides a magnetic lens thermal management system based on combined PCM to alleviate the heat loss and micro-vibration problems of magnetic lenses during operation. Summary of the Invention

[0006] In view of this, the present invention proposes a combined PCM magnetic lens heat storage and vibration reduction system and its application. Without changing the original water cooling system of the magnetic lens, a combined PCM embedding method is used to replace the epoxy resin encapsulation material of the conventional magnetic lens coil, thereby solving the problems of uncontrollable coil temperature and mechanical micro-vibration after the pole shoe and coil are assembled in the prior art.

[0007] The technical solution of this invention is implemented as follows:

[0008] On one hand, the present invention provides a magnetic lens heat storage and vibration damping system and application of a combined PCM, including a magnetic lens, a magnetic lens water cooling heat dissipation system and a phase change heat storage system. The magnetic lens includes a shell, pole shoes and a heat source, and the magnetic lens water cooling heat dissipation system includes a water cooling medium, a water cooling pipe and a liquid pump.

[0009] The phase change thermal energy storage system includes a combined PCM, which consists of a first PCM, a second PCM, and a third PCM. The first PCM encloses the heat source, the second PCM encloses the first PCM, and the third PCM encloses the second PCM. The phase change temperatures of the first PCM, the second PCM, and the third PCM decrease sequentially.

[0010] The implementation process of the magnetic lens heat storage and vibration damping system of the combined PCM includes the following steps:

[0011] Based on computer-aided simulation and experimental measurement, the temperature variation range of the heat source's working state is determined and denoted as T1-T2;

[0012] Based on the temperature change range, the phase transition temperature is selected as T. m1 The PCM is used as the first PCM, and the phase transition temperature is T. m2 The PCM is used as the second PCM, and the phase transition temperature is T. m3 The PCM is used as the third PCM;

[0013] The first PCM is melted into a molten state, and the heat source is immersed in the molten first PCM. After the first PCM solidifies, the heat source is immersed in the molten second PCM using the same method. After solidification, it is immersed in the molten third PCM again. Then, aluminum foil is used to seal the outer surface of the third PCM, thus obtaining the magnetic lens heat storage and vibration damping system of the combined PCM. This ensures that the heat source is radially embedded by the first PCM, the second PCM, and the third PCM sequentially, and longitudinally, the first PCM, the second PCM, and the third PCM embed the gap between the height of the heat source and the outer shell. The operating temperature of the magnetic lens heat storage and vibration damping system of the combined PCM is T1. ’ ~T2 ’And T2 ’ / T2<1;

[0014] Phase change thermal storage, also known as latent heat storage, refers to the process by which energy storage materials absorb or release heat during a phase change to achieve heat storage and release. The process of storing and releasing energy is determined by the melting point and ambient temperature. When the temperature rises to the melting point of the energy storage material, the material changes from a solid state to a molten state, and some of the heat from the surrounding environment is stored in the energy storage material. When the temperature of the surrounding environment drops to the critical point of the molten state, the energy storage material releases heat and changes from a molten state to a solid state, which is an exothermic process. This cycle repeats, forming a magnetic lens thermal storage system.

[0015] More preferably, the phase transition temperatures of the first PCM, the second PCM, and the third PCM satisfy condition T. m1 >T2>T m2 >T m3 T m1 / T m2 =T m2 / T m3 ±0.01.

[0016] More preferably, the first PCM, the second PCM, and the third PCM are arranged in a combination and distributed sequentially outside the heat source.

[0017] More preferably, the volume ratio of the first PCM, the second PCM and the third PCM is (2-3):(2-4):(4-6).

[0018] More preferably, T1 is 20℃~25℃, and T2≤50℃.

[0019] More preferably, the heat source includes at least one of an electromagnetic coil, an electromagnet, or a permanent magnet.

[0020] More preferably, the selected PCM includes an organic solid-liquid PCM. More preferably, the organic solid-liquid PCM includes fatty acids, aliphatic hydrocarbons, or polyenols.

[0021] More preferably, the organic solid-liquid PCM includes paraffin PCM.

[0022] More preferably, when the PCM is selected as paraffin PCM, the phase transition temperatures of the first PCM, the second PCM, and the third PCM are, in sequence, T. m1 =54.85℃, T m2 =48.85℃, T m3 =45.85℃.

[0023] On the other hand, the present invention also provides the application of the magnetic lens heat storage and vibration reduction system of the combined PCM described in the first aspect in the field of electro-optics.

[0024] The combined PCM magnetic lens heat storage and vibration reduction system and its application of the present invention have the following advantages over the prior art:

[0025] Currently, the application of PCM (Polymerized Condensate) in electro-optical equipment for phase change heat transfer is not widespread, and it suffers from problems such as poor temperature control adjustability, small temperature control range, and low thermal energy utilization compared to single PCMs. This invention uses a combined PCM to embed the magnetic lens coil, arranging three PCMs with different phase change temperatures into a "combined PCM," which greatly improves the temperature control range and interval, while effectively enhancing the heat storage performance of the PCM. By rationally selecting the PCM volume ratio and phase change temperature, a wide temperature adjustable range can be achieved, with performance far exceeding that of a single PCM. Furthermore, using organic solid-liquid PCM to embed the magnetic lens heat source, instead of the existing epoxy resin encapsulation, can better improve thermal management and micro-vibration during magnetic lens operation. Compared to a single PCM, the combined PCM, due to its smaller temperature fluctuation near the heat source and flexible volume ratio adjustment, will result in higher energy utilization and a wider temperature adjustable range.

[0026] Existing reports on improvements to the application of magnetic lenses in heat storage fall into two main categories: altering the positional distribution of water-cooling pipes and disrupting the original water-cooling circulation system of the magnetic lens before introducing a single PCM. After disrupting the original water-cooling structure of the magnetic lens, the idea of ​​using a single PCM for thermal management is impractical and suffers from weak temperature control. Based on previous research, this invention improves the thermal management of the magnetic lens under operating conditions by introducing multiple layers of PCM without disrupting the original cooling system of the magnetic lens coil. Furthermore, the first PCM is close to the heat source, and the third PCM is close to the pole piece, so theoretically, the third PCM can also absorb some of the temperature changes inside the pole piece. Simultaneously, the mechanical vibration problem of the magnetic lens is also improved.

[0027] Compared with existing applications of PCM in the field of thermal management, this invention provides a method of radial embedding of multi-layer PCM for thermal management of magnetic lenses, which avoids the gap between the magnetic lens heat source and the pole piece to the greatest extent, reduces the uneven stress on the magnetic lens, improves the mechanical stability of the magnetic lens, and is conducive to the centering and assembly of components. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] 1-Inlet, 2-Outlet, 3-Magnetic lens housing, 4-Water-cooled tube wall, 5-Liquid pump, 6-First PCM, 7-Second PCM, 8-Third PCM, 9-Lower pole shoe, 10-Upper pole shoe, 11-Magnetic lens coil, 12-Water-cooled tube support plate, 13-Water-cooled tube;

[0030] Figure 1 This is a simplified diagram of the latent heat of phase change and heat storage of the combined PCM of the present invention;

[0031] Figure 2 This is a three-dimensional structural diagram of the magnetic lens water-cooling tube coil of the present invention;

[0032] Figure 3 This is a three-dimensional structural diagram of the magnetic lens water-cooling pipe surrounding the present invention;

[0033] Figure 4 A simplified diagram of the combined PCM of the present invention acting on the magnetic lens of the water-cooled tube coil;

[0034] Figure 5 A simplified diagram of the combined PCM of the present invention acting on a magnetic lens surrounding a water-cooling pipe;

[0035] Figure 6 This is a front view of the combined PCM structure of the present invention;

[0036] Figure 7 This is a top view of the combined PCM structure of the present invention;

[0037] Figure 8 This is a schematic diagram of the focusing of a particle beam by the combined PCM magnetic lens coil of the present invention;

[0038] Figure 9 This is a schematic diagram of the charged particle beam system composed of magnetic lenses in the combined PCM of the present invention. Detailed Implementation

[0039] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0040] Currently, mainstream magnetic lens coils generally employ forced convection for temperature control, such as water cooling, air cooling, and oil cooling. These methods are prone to temperature instability and uneven temperature field distribution, making it difficult to guarantee effective cooling. Furthermore, temperature fluctuations can cause uneven magnetic field distribution and shifts in the position of the strong magnetic field, affecting the stability of the magnetic field performance. Regarding the aforementioned forced convection cooling methods, water cooling is currently the most common due to its relatively high controllability. However, when water is used as the heat transfer medium injected into a water-cooled pipe to cool the magnetic lens heat source, the high specific heat of water leads to uncontrollable heat absorption, failing to provide quantitative temperature control. Moreover, due to the mechanical complexity of magnetic lenses, when integrated cooling pipes are used for temperature control, it is difficult to achieve good thermal contact between the cooling pipe and the magnetic coil, increasing the uncontrollable variables in water cooling.

[0041] Furthermore, when the magnetic lens is in operation, the magnetic lens coil continuously generates heat after being energized, and the temperature field caused by power consumption will always exist. This will prevent the damping ring from covering the entire coil assembly over a large area. Therefore, the internal damping of a typical magnetic lens can only add 1-2 damping rings at specific locations, which will cause the entire magnetic lens to be subjected to uneven force during operation. This uneven force will affect the axial magnetic field distribution of the magnetic lens, directly affecting the electromagnetic focusing and deflection effect of the magnetic lens.

[0042] In traditional charged particle beam devices, the magnetic lens pole pieces, housing, and coil are not fixedly connected after assembly. The pole pieces and housing are mechanically mounted onto the magnetic lens coil coil. However, it is difficult to perfectly match the shape of the coil coil with the external structure of the pole piece housing in the design. Generally, the gaps caused by theoretical design are difficult to maintain within acceptable tolerances during mechanical assembly.

[0043] This invention provides a combined PCM magnetic lens heat storage and vibration damping system and its application, including a magnetic lens, a magnetic lens water-cooling system, and a combined phase change heat storage system. The magnetic lens includes a shell, pole shoes, and a heat source. The magnetic lens water-cooling system includes a water-cooling medium, water-cooling pipes, and a liquid pump. Furthermore, by using a combined PCM embedding method, it solves the problems of uncontrollable coil temperature during magnetic lens operation and mechanical vibration after pole shoes and coil assembly in existing technologies. The combined PCM includes a first PCM, a second PCM, and a third PCM, where the phase change temperature of the first PCM is T. m1 The phase transition temperature of the second PCM is T. m2 The phase transition temperature of the third PCM is T. m3 T m1 >T2>T m2 >Tm3 The first PCM, the second PCM, and the third PCM are arranged in a combination along the radial direction of the heat source and distributed sequentially outside the heat source.

[0044] The temperature variation range of the heat source's operating state is defined as T1-T2, and the operating temperature T1 of the magnetic lens heat storage and vibration damping system and its application in the combined PCM is... ’ ~T2 ’ This allows the material to change from a solid state to a molten state when the temperature rises to its melting point, storing some of the heat in the PCM (Polymerized Magnetic Lens), which is a heat storage process. When the temperature of the surrounding environment drops to its melting point, the material releases heat and changes from a molten state to a solid state, which is an exothermic process, i.e., an energy release process. This cycle repeats continuously, forming a magnetic lens heat storage system. In addition, the use of three layers of PCM to embed the magnetic lens coil during the embedding process also maximizes the filling of the gap error between the magnetic lens heat source and the pole shoe during assembly, improving the mechanical stability of the magnetic lens.

[0045] The present invention will be further described below through specific embodiments.

[0046] Example 1

[0047] This embodiment provides a magnetic lens heat storage and vibration damping system for a combined PCM, including a heat source, a magnetic lens water cooling system, and a combined phase change heat storage system.

[0048] The magnetic lens includes a housing, pole shoes, and a heat source; the magnetic lens water-cooling heat dissipation system includes a water-cooling medium, water-cooling pipes, and a liquid pump; the phase change heat storage system includes a combined PCM, which is composed of a first PCM, a second PCM, and a third PCM.

[0049] The heat source includes at least one of an electromagnetic coil, an electromagnet, or a permanent magnet; the outer shell is an iron shell; the pole shoes are made of soft magnetic material; and the coil is a copper coil.

[0050] The implementation process of the magnetic lens heat storage and vibration damping system of the combined PCM and its application includes the following steps:

[0051] The first PCM is melted into a molten state, and the heat source is immersed in the molten first PCM. After the first PCM solidifies, the solidified first PCM is then immersed in the molten second PCM. After the second PCM solidifies, the solidified second PCM is then immersed in the molten third PCM. After the third PCM solidifies, the outer surface of the third PCM is sealed with aluminum foil to obtain the magnetic lens heat storage and vibration damping system of the combined PCM. This ensures that the heat source is radially embedded by the first PCM, the second PCM, and the third PCM, and longitudinally, the first PCM, the second PCM, and the third PCM enclose the gap between the heat source and the outer shell. The operating temperature of the magnetic lens heat storage and vibration damping system of the combined PCM and its application is T1. ’ ~T2 ’ And T2 ’ / T2<1.

[0052] The first PCM, the second PCM, and the third PCM are arranged in a radial combination outside the heat source to form a phase change heat storage system for the magnetic lens, thereby controlling the temperature change of the magnetic lens heat source during operation.

[0053] Due to the defects of inorganic PCMs, such as supercooling and phase separation, and the corrosiveness of some inorganic PCMs, this technical route mainly uses organic PCMs for temperature control of the magnetic lens heat source. In organic PCMs, the same material can have its phase transition temperature varied from low to high by changing the material synthesis parameters, thus forming low-temperature PCMs, medium-temperature PCMs, and high-temperature PCMs. Since this technology involves embedding the heat source within molten PCM, organic PCMs with a solid-liquid conversion mechanism are required to construct the phase change heat storage system. Therefore, the PCMs selected in this invention include organic solid-liquid PCMs, specifically paraffinic organic PCMs.

[0054] like Figure 1 This is a simplified diagram of the latent heat storage of phase change using the combined PCM in this invention. The first PCM is PCM1, the second PCM is PCM2, and the third PCM is PCM3. PCMs with different phase change temperatures are combined. During the entire phase change process, the PCM undergoes a change from a solid state to a solid-liquid mixed state and then to a molten state.

[0055] like Figure 2 The diagram shows a three-dimensional schematic of the coiled structure of the magnetic lens water-cooling tube in Example 1. The magnetic lens water-cooling heat dissipation system has the water-cooling tube coiled on the magnetic lens coil. It is mainly composed of three parts: water-cooling tube wall-4, water-cooling tube support plate-12, and water-cooling tube-13. The three parts are combined to form the magnetic lens water-cooling heat dissipation system.

[0056] Example 2

[0057] This embodiment provides a combined PCM magnetic lens heat storage and vibration damping system. The difference from Embodiment 1 is that in this embodiment, the water-cooled heat dissipation system has water-cooling pipes wrapped around the magnetic lens coil. For example... Figure 3 The diagram shows a simplified heat dissipation structure of a magnetic lens water-cooled pipe in Example 2. It consists of a magnetic lens shell-3, a water-cooled pipe wall-4, a lower pole shoe-9, an upper pole shoe-10, a magnetic lens coil-11, and a water-cooled pipe-13, forming a strong convection heat dissipation system in which the water-cooled pipe surrounds the magnetic lens coil.

[0058] Example 3

[0059] This embodiment provides a magnetic lens heat storage and vibration reduction system for a combined PCM. The difference from Embodiment 1 is that the combined PCMs are arranged sequentially outside the heat source.

[0060] like Figure 4 For the purpose of Figure 2 The diagram shows the water-cooled tube winding method and the structural diagram of the combined PCM acting on the magnetic lens coil. It includes an inlet-1, an outlet-2, a magnetic lens housing-3, a water-cooled tube wall-4, a liquid pump-5, a first PCM-6, a first PCM-7, a first PCM-8, a lower pole shoe-9, an upper pole shoe-10, a magnetic lens coil-11, a water-cooled tube support plate-12, and a water-cooled tube-13, which together constitute a PCM magnetic lens composite structure.

[0061] Example 4

[0062] This embodiment provides a magnetic lens heat storage and vibration reduction system for a combined PCM. The difference from Embodiment 2 is that the combined PCMs are arranged sequentially outside the heat source.

[0063] like Figure 5 For the purpose of Figure 3 The diagram shows a water-cooled pipe winding configuration, with the combined PCM acting on the magnetic lens coil. It includes an inlet-1, an outlet-2, a magnetic lens housing-3, a water-cooled pipe wall-4, first PCM-6, first PCM-7, first PCM-8, a lower pole shoe-9, an upper pole shoe-10, a magnetic lens coil-11, a water-cooled pipe support plate-12, and a water-cooled pipe-13, which together form another type of PCM magnetic lens composite structure.

[0064] On the other hand, the magnetic lens will cause slight vibrations between the coil and the yoke due to the magnetic field during operation. The general way to eliminate this vibration is to introduce a damping coil between the magnetic lens shell and the coil. The material, position and damping effect of the damping coil will increase the complexity of the magnetic lens design.

[0065] Therefore, Example 5 is set up based on Example 1.

[0066] Example 5

[0067] This embodiment provides a magnetic lens heat storage and vibration damping system for a combined PCM. The implementation process of the magnetic lens heat storage and vibration damping system for the combined PCM includes the following steps:

[0068] Based on computer-aided simulation and experimental measurement, the temperature variation range of the magnetic lens under different excitation currents was calculated using the multiphysics simulation software COMSOL Multiphysics and the finite element method. Then, the temperature variation range and distribution of the magnetic lens under different excitation currents were measured using a temperature measuring instrument. The theoretical and experimental results were compared to obtain the final T1-T2. The temperature variation range of the heat source working state was determined and denoted as T1-T2.

[0069] T1 is 24℃, and T2 ≤ 60℃;

[0070] Based on the temperature change range, the phase transition temperature is selected as T. m1 The PCM is used as the first PCM, and the phase transition temperature is T. m2 The PCM is used as the second PCM, and the phase transition temperature is T. m3 The PCM is used as the third PCM;

[0071] Currently, gaps formed during the assembly of existing pole shoes, housings, and heat sources can affect the mechanical alignment of the magnetic lens assembly. Therefore, this invention melts the first PCM into a molten state, immerses the heat source in the molten first PCM, and after the first PCM solidifies, immerses the solidified first PCM in a molten second PCM, and after the second PCM solidifies, immerses the solidified second PCM in a molten third PCM. After the third PCM solidifies, its outer surface is sealed with aluminum foil. This allows the heat source to be radially embedded by a combination of PCMs with phase transition temperatures decreasing from high to low, and longitudinally, the first, second, and third PCMs fill the gaps formed between the heat source and the housing. This three-layer PCM embedding method effectively fills the gap errors in the mechanical assembly of the magnetic lens after design, significantly improving the mechanical alignment and vibration reduction issues during assembly and operation. For this purpose, the phase transition temperatures of the first, second, and third PCMs satisfy condition T. m1 >T2>T m2 >T m3 T m1 / T m2 =T m2 / T m3 ±0.01;

[0072] When the organic solid-liquid PCM is a paraffinic organic PCM, the phase transition temperatures of the first PCM, the second PCM, and the third PCM are respectively T m1 =54.85℃, T m2 =48.85℃, T m3 =45.85℃;

[0073] The change in the operating temperature of the magnetic lens before and after PCM immersion was tested and denoted as T1. ’ ~T2 ’ And adjust the volume ratio between the combined PCMs, i.e., V1:V2:V3 = 2:2:6, so that T2 ’ / T2<1; When the temperature rises to the melting point of the material, the material changes from a solid state to a molten state, and some of the heat in the surrounding environment is stored in the PCM, which is the heat storage process; when the temperature of the surrounding environment drops to the melting point, the material releases heat, and the material changes from a molten state to a solid state, which is the heat release process; this cycle repeats, forming a phase change heat storage system that can be used for magnetic lenses, achieving the effect of cyclic heat storage.

[0074] Example 6

[0075] This embodiment provides a magnetic lens heat storage and vibration reduction system for a combined PCM and its application process. The difference from Embodiment 5 is that the volume ratio between the combined PCMs is V1:V2:V3 = 3:3:4.

[0076] like Figure 6 The image shows a front view of the improved combined PCM used in Example 6. PCMs with different phase change temperatures are used to sequentially enclose the heat source, and are designated as the first PCM, second PCM, and third PCM. They are arranged from the inside out in descending order of phase change temperature, with the first PCM being the one closest to the heat source. By combining PCMs with different phase change temperatures, the control range and capability of the PCM over the heat source temperature are increased. Since the phase change temperatures of the first PCM, second PCM, and third PCM satisfy condition T... m1 >T2>T m2 >T m3 When the volume ratio of the first PCM increases (3:3:4 compared to 2:2:6), the control range of the combined PCM on the heat source temperature also increases, T2 ’ It's closer to T2.

[0077] like Figure 7 This is a top view of the improved combined PCM used in Example 6, and is the same as... Figure 6 The PCM arrangement method involves arranging PCMs with different phase change temperatures in descending order of phase change temperature from the inside out, with the 6th one closest to the heat source being the first PCM.

[0078] Example 7

[0079] This embodiment provides a magnetic lens heat storage and vibration reduction system for a combined PCM and its application. The magnetic lens heat storage and vibration reduction system for a combined PCM described in Embodiment 1 is applied in the field of electron optics, especially charged particle accelerators, charged particle microscopy, charged particle beam processing equipment, etc.

[0080] like Figure 8 The diagram shows a simplified representation of the charged particle beam system constructed using the combined PCM magnetic lens in Example 7. It includes four magnetic lenses, one aperture, one particle emission source, and one imaging plane. The vertical line in the middle is the central axis of the particle beam's movement, and the dashed line is a diagram showing the trajectory changes of the particle beam. By using the combined PCM magnetic lens described in this invention, the charged particle beam system constructed therein can be applied to particle beam-related equipment.

[0081] like Figure 9 This is a schematic diagram of the focusing and rotation of the particle beam by the magnetic lens in Example 7. When current is applied to the coil, the magnetic coil will generate a magnetic field. The strength of the magnetic field can be controlled by adjusting the current. When the current is larger, the temperature effect generated by the coil will be more obvious. When the particle beam emitted from the particle source passes through the magnetic lens, it will undergo focusing, deflection and rotation characteristics under the action of the magnetic field generated by the magnetic lens.

[0082] In summary, this invention proposes a combined PCM magnetic lens heat storage and vibration damping system and its application, comprising the following steps: determining the temperature variation range of the magnetic lens heat source's operating state; selecting PCMs with different phase transition temperatures as the first, second, and third PCMs to form a combined PCM structure based on the temperature variation range; melting the aforementioned PCMs into a molten state, and through a process of sequentially immersing and solidifying the magnetic lens heat source, embedding the heat source radially within the combined PCMs with phase transition temperatures varying from high to low; and adjusting the volume ratio between the combined PCMs by comparing and analyzing the changes in the magnetic lens's operating temperature before and after embedding the heat source with the combined PCMs. This system provides a uniform and temperature-controllable thermal management system for the magnetic lens, while simultaneously enhancing the thermal and mechanical stability of related particle beam devices employing magnetic lenses.

[0083] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A combined PCM magnetic lens heat storage and vibration damping system, comprising a magnetic lens, a magnetic lens water-cooling heat dissipation system, and a combined phase change heat storage system, wherein the magnetic lens includes a shell, pole shoes, and a heat source, and the magnetic lens water-cooling heat dissipation system includes a water-cooling medium, water-cooling pipes, and a liquid pump, characterized in that, The combined phase change thermal energy storage system consists of a first PCM, a second PCM, and a third PCM. The first PCM encloses the heat source, the second PCM encloses the first PCM, and the third PCM encloses the second PCM. The phase change temperatures of the first PCM, second PCM, and third PCM decrease sequentially. The implementation process of the magnetic lens thermal energy storage and vibration damping system of the combined PCM includes the following steps: Based on computer-aided simulation and experimental measurement, the temperature variation range of the heat source's working state is determined and denoted as T1-T2; The phase transition temperature of the first PCM is T m1 The phase transition temperature of the second PCM is T. m2 The phase transition temperature of the third PCM is T. m3 The phase transition temperatures satisfy T m1 >T2>T m2 >T m3 ; The first PCM is melted into a molten state, and the heat source is immersed in the molten first PCM. After the first PCM solidifies, the heat source is sequentially immersed in the molten second and third PCMs using the same method. After the third PCM solidifies, its outer surface is sealed with aluminum foil, resulting in the magnetic lens heat storage and vibration damping system and application of the combined PCM. This system ensures that the heat source is radially embedded by the first, second, and third PCMs, and longitudinally, the first, second, and third PCMs fill the gap between the heat source and the outer shell, and also fill the gap between the heat source and the pole shoe. The operating temperature of the magnetic lens heat storage and vibration damping system and application of the combined PCM is T1. ’ ~T2 ’ And T2 ’ / T2<1, The combined PCM includes organic solid-liquid PCM.

2. The magnetic lens heat storage and vibration damping system of the combined PCM as described in claim 1, characterized in that, The phase transition temperatures of the first PCM, the second PCM, and the third PCM satisfy condition T. m1 / T m2 =T m2 / T m3 ±0.

01.

3. The magnetic lens heat storage and vibration damping system of the combined PCM as described in claim 1, characterized in that, The first PCM, the second PCM, and the third PCM are arranged sequentially outside the heat source in a combination arrangement along the radial direction of the heat source.

4. The magnetic lens heat storage and vibration damping system of the combined PCM as described in claim 1, characterized in that, The volume ratio of the first PCM, the second PCM and the third PCM is (2-3):(2-4):(4-6).

5. The magnetic lens heat storage and vibration damping system of the combined PCM as described in claim 1, characterized in that, T1 is 20℃~25℃, and T2≤50℃.

6. The magnetic lens heat storage and vibration damping system of the combined PCM as described in claim 1, characterized in that, The heat source includes at least one of an electromagnetic coil, an electromagnet, and a permanent magnet.

7. The magnetic lens heat storage and vibration damping system of the combined PCM as described in claim 1, characterized in that, The organic solid-liquid PCM includes fatty acids, aliphatic hydrocarbons, or polyenols.

8. The magnetic lens heat storage and vibration damping system of the combined PCM as described in claim 7, characterized in that, The organic solid-liquid PCM also includes paraffin PCM.

9. The application of the magnetic lens heat storage and vibration reduction system of the combined PCM as described in any one of claims 1-8 in the field of electro-optics.

Images