Anode assembly and processing method thereof

Abstract

The invention belongs to the technical field of X-ray tubes, and discloses an anode assembly and a processing method thereof.The anode assembly comprises a molybdenum reflector plate, a molybdenum rotor assembly and a middle layer, the middle layer is made of metal and arranged between the molybdenum reflector plate and the molybdenum rotor assembly through the processing method, and in the heating process, the molybdenum rotor assembly is heated through the middle layer; the middle layer can effectively absorb and buffer thermal stress and shrinkage stress generated by heating and cooling of molybdenum components on the two sides through plastic deformation of the middle layer, and the risk that microcracks are generated due to stress concentration is greatly reduced. As the chemical affinity of the intermediate layer to impurity atoms is higher than that of a molybdenum material, the intermediate layer can be ensured to preferentially react with harmful impurities in an interface area to form a stable compound in a protective atmosphere or a vacuum environment in the welding process, so that segregation of the impurities at the grain boundary of molybdenum is prevented, and the welding quality is improved. The microstructure and toughness of a molybdenum heat affected zone are remarkably improved, and the grain boundary cracking resistance is enhanced.

Description

Technical Field

[0001] This invention relates to the field of X-ray tube technology, and in particular to an anode assembly and its processing method. Background Technology

[0002] In the manufacturing process of CT tubes, in order to reduce the heat generated by the target disk in the X-ray tube from being conducted to the bearing and to reduce the wear caused by the bearing under high temperature and high speed rotation, heat reflectors are often installed on the outside of the rotor assembly to reflect the heat radiated to the bearing back, thereby reducing the heat conduction to the bearing.

[0003] Molybdenum metal is a preferred material for manufacturing X-ray tube anode components and reflectors due to its high melting point (approximately 2620℃), excellent high-temperature strength, and good X-ray penetrability. Specifically, the rotor assembly is preferably made of TZM molybdenum alloy, and the reflector is preferably made of pure molybdenum. In actual production, the reflector and rotor assembly are typically assembled and fixed using direct molybdenum-molybdenum connections (including Mo-Mo or Mo-TZM connections), such as laser welding or electron beam welding.

[0004] However, molybdenum materials exhibit poor plasticity and low toughness at room temperature. During welding, the joint area experiences intense localized heating and rapid cooling, generating significant welding thermal stress. Since molybdenum cannot effectively release this stress through plastic deformation, stress becomes highly concentrated in the weld and heat-affected zone. Simultaneously, molybdenum is extremely sensitive to impurity atoms such as oxygen, nitrogen, and carbon, and tends to segregate at grain boundaries at high temperatures, severely weakening grain boundary bonding and exacerbating material brittleness.

[0005] The combined effects of stress concentration and grain boundary weakening make it extremely easy for microcracks to initiate in the recrystallization zone or weld. These cracks will further propagate under the cyclic thermal shocks and mechanical vibrations experienced by the connection structure during subsequent operation, eventually leading to the failure of the connection structure and seriously affecting the service life and reliability of the anode assembly and even the entire X-ray tube.

[0006] To address the aforementioned issues, existing technologies primarily employ two approaches: First, optimizing process parameters such as power, speed, vacuum level, and protective gas flow rate to control heat input and reduce temperature gradients in the fastening structure area, thereby lowering thermal stress. Second, after molybdenum-molybdenum processing and assembly, the anode assembly undergoes low-temperature annealing. Typically, the assembly is heated to 500℃-700℃, held for 2-4 hours, and then cooled in the furnace. This heat treatment causes metal atoms in the processed area to diffuse, mitigating lattice distortion, releasing some residual stress, and reducing the risk of crack formation.

[0007] However, the first approach reduces heat input to lower thermal stress, which often leads to insufficient penetration and a decrease in the load-bearing capacity of the anode components, making it difficult to meet the demands of high-power loads. The second approach increases the production process and cycle, and if the heat treatment process is not properly controlled, it can easily cause component deformation and affect dimensional accuracy.

[0008] Therefore, the above problems urgently need to be solved. Summary of the Invention

[0009] The purpose of this invention is to provide an anode assembly and its processing method to prevent microcracks from forming in the recrystallization zone or weld between the reflector and the rotor assembly during connection or subsequent use, thereby improving the service life and reliability of the anode assembly.

[0010] To achieve this objective, the present invention adopts the following technical solution:

[0011] Anode assembly processing method, comprising the following steps:

[0012] S1: Provides molybdenum reflectors and molybdenum rotor assemblies;

[0013] S2: Provide an intermediate layer made of a third metal material that is metallurgically compatible with the molybdenum reflector and the molybdenum rotor assembly;

[0014] S3: The intermediate layer is disposed between the molybdenum reflector and the molybdenum rotor assembly;

[0015] S4: In a protective atmosphere or vacuum environment, the connection area of ​​the molybdenum reflective sheet, the intermediate layer and the molybdenum rotor assembly is heated so that the three are bonded together by metallurgical means.

[0016] The intermediate layer has higher plasticity at room temperature and higher affinity for impurity atoms in the interface region between the three materials than the molybdenum material. During heating and cooling, it absorbs and releases thermal stress and shrinkage stress from the molybdenum materials on both sides through its own plastic deformation, and reacts with the impurity atoms before the molybdenum material, thereby inhibiting the initiation and propagation of cracks in the recrystallization zone of the molybdenum material or at the weld.

[0017] Preferably, the metal material is titanium, zirconium, or liquid brazing filler metal.

[0018] Preferably, the metallurgical method is laser welding, argon arc welding, or brazing.

[0019] Preferably, the absolute value of the difference between the thermal expansion coefficient of the metal material and the thermal expansion coefficient of the molybdenum material is not greater than 5.0 μm / m·K.

[0020] Preferably, in step S4, before heating the molybdenum reflector, the intermediate layer, and the molybdenum rotor assembly, the molybdenum reflector, the molybdenum rotor assembly, and the metal intermediate layer need to be ultrasonically cleaned and degassed at high temperature using a vacuum furnace.

[0021] An anode assembly includes a molybdenum reflector, a molybdenum rotor assembly, and an intermediate layer. The intermediate layer is disposed between the molybdenum reflector and the molybdenum rotor assembly, and is made of a third metal material that is metallurgically compatible with the molybdenum reflector and the molybdenum rotor assembly. The intermediate layer has higher plasticity at room temperature and higher affinity for impurity atoms in the interface region between the three materials than the molybdenum material. During heating and cooling, it absorbs and releases thermal stress and shrinkage stress from the molybdenum materials on both sides through its own plastic deformation, and reacts with the impurity atoms before the molybdenum material, thereby inhibiting the initiation and propagation of cracks in the recrystallization zone of the molybdenum material or at the weld.

[0022] Preferably, the intermediate layer has a cylindrical structure, and the intermediate layer is screwed to the molybdenum rotor assembly, and the molybdenum reflector is screwed to the intermediate layer;

[0023] The intermediate layer is connected to the molybdenum rotor assembly and the molybdenum reflector by laser welding.

[0024] Preferably, the molybdenum reflector is screwed to the molybdenum rotor assembly, and the molybdenum reflector and the molybdenum rotor assembly form a receiving groove for accommodating the intermediate layer.

[0025] Preferably, the intermediate layer is made of titanium or zirconium, which forms a cylindrical structure that conforms to the shape of the receiving groove, and is connected to the molybdenum rotor assembly and the molybdenum reflector by laser welding; or;

[0026] The intermediate layer is made of liquid brazing filler metal, which fills the receiving groove and is connected to the molybdenum rotor assembly and the molybdenum reflector by brazing.

[0027] Preferably, the molybdenum reflector is screwed to the molybdenum rotor assembly, the intermediate layer is a columnar structure that penetrates the molybdenum reflector and is embedded in the molybdenum rotor assembly, and is connected to the molybdenum rotor assembly and the molybdenum reflector by argon arc welding.

[0028] The beneficial effects of this invention are:

[0029] The present invention proposes an anode assembly and its processing method, in which an intermediate layer is provided between a molybdenum reflector and a molybdenum rotor assembly. During heating, the intermediate layer can effectively absorb and buffer the thermal and shrinkage stresses generated by heating and cooling of the molybdenum components on both sides through its own plastic deformation, greatly reducing the risk of microcracks initiating due to stress concentration. Furthermore, because the intermediate layer has a higher chemical affinity for impurity atoms than molybdenum material, it can avoid preferentially reacting with oxygen and nitrogen elements in the air to form an oxide film under a protective atmosphere or vacuum environment. This ensures that during welding, the intermediate layer preferentially reacts with these harmful impurities in the interface region to form stable compounds, thereby preventing impurities from segregating at the grain boundaries of molybdenum, significantly improving the microstructure and toughness of the heat-affected zone of molybdenum, and enhancing the resistance to grain boundary cracking. Attached Figure Description

[0030] Figure 1 This is a flowchart illustrating the anode component processing method in this invention;

[0031] Figure 2 This is one of the structural schematic diagrams of the anode assembly in this invention;

[0032] Figure 3 yes Figure 2 Enlarged view of a portion of point A in the middle;

[0033] Figure 4 This is the second schematic diagram of the anode assembly in this invention;

[0034] Figure 5 yes Figure 4 Enlarged view of a section at point B in the middle;

[0035] Figure 6 This is the third schematic diagram of the anode assembly in this invention;

[0036] Figure 7 yes Figure 6 Enlarged view of a section at point C.

[0037] In the picture:

[0038] 1. Molybdenum reflector; 2. Molybdenum rotor assembly; 3. Intermediate layer. Detailed Implementation

[0039] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0040] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0041] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0042] In the description of this embodiment, the terms "upper," "lower," "left," and "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0043] Please see Figures 1 to 7 This embodiment proposes a method for processing an anode assembly, which includes the following steps:

[0044] S1: Provides a molybdenum reflector 1 and a molybdenum rotor assembly 2;

[0045] S2: Provide an intermediate layer 3, which is made of a third metal material that is metallurgically compatible with the molybdenum reflector 1 and the molybdenum rotor assembly 2. The third metal refers to a metal material that is different from the molybdenum reflector 1 and the molybdenum rotor assembly 2.

[0046] S3: The intermediate layer 3 is placed between the molybdenum reflector 1 and the molybdenum rotor assembly 2;

[0047] S4: In a protective atmosphere or vacuum environment, the connection area of ​​the molybdenum reflector 1, the intermediate layer 3 and the molybdenum rotor assembly 2 is heated so that the three are bonded together by metallurgy.

[0048] Among them, the intermediate layer 3 has higher plasticity at room temperature and higher affinity for impurity atoms in the interface region between the three than the molybdenum material. During heating and cooling, it can absorb and release thermal stress and shrinkage stress from the molybdenum materials on both sides through its own plastic deformation, and react with impurity atoms before the molybdenum material, thereby inhibiting the initiation and propagation of cracks in the recrystallization zone of the molybdenum material or at the weld.

[0049] It should be noted that, regardless of whether it is pure molybdenum or TZM alloy, trace amounts of impurity atoms such as oxygen and nitrogen will inevitably dissolve during the powder metallurgy or smelting process. These impurity atoms exist in the form of interstitial solid solutions within the metal lattice. When these three elements are combined in a metallurgical manner, oxygen and nitrogen impurity atoms can enter the grain boundaries. When oxygen and nitrogen atoms accumulate to a certain extent at the grain boundaries, they form stable oxide or nitride thin layers or agglomerates. Although these can temporarily hinder grain growth, they severely weaken the metallic bonding forces between the grain boundary atoms.

[0050] In this embodiment, an intermediate layer 3 is provided between the molybdenum reflector 1 and the molybdenum rotor assembly 2. During the heating process, the intermediate layer 3 can effectively absorb and buffer the thermal stress and shrinkage stress generated by heating and cooling of the molybdenum components on both sides through its own plastic deformation, greatly reducing the risk of microcracks initiating due to stress concentration. Furthermore, since the intermediate layer 3 has a higher chemical affinity for impurity atoms than molybdenum material, it can avoid preferentially reacting with oxygen and nitrogen elements in the air under a protective atmosphere or vacuum environment. This ensures that the intermediate layer 3 preferentially reacts with harmful impurities in the interface region during the welding process, forming stable compounds. This prevents impurities from segregating at the molybdenum grain boundaries, significantly improves the microstructure and toughness of the molybdenum grain boundaries, and enhances the resistance to grain boundary cracking.

[0051] Furthermore, in step S4, before heating the molybdenum reflector 1, the intermediate layer 3, and the molybdenum rotor assembly 2, the molybdenum reflector 1, the molybdenum rotor assembly 2, and the metal intermediate layer 3 need to be ultrasonically cleaned and degassed at high temperature using a vacuum furnace. It is understood that ultrasonic cleaning removes physical contaminants such as grease, dust, and processing residues from the surfaces of these three components. The cleaning solution used during the cleaning process is preferably alcohol or pure water to ensure cleaning quality. Vacuum degassed not only removes molecules such as water vapor, oxygen, and nitrogen adsorbed on the metal surface from the air, but also diffuses trace amounts of adsorbed gases or low-melting-point impurities within the metal to the surface and removes them. The temperature inside the vacuum furnace is preferably between 400°C and 700°C. This setup further improves the connection quality of the three components during the metallurgical process and extends the service life of the anode assembly.

[0052] Based on the above, this embodiment also proposes an anode assembly, which includes a molybdenum reflector 1, a molybdenum rotor assembly 2, and an intermediate layer 3. The intermediate layer 3 is disposed between the molybdenum reflector 1 and the molybdenum rotor assembly 2, and the intermediate layer 3 is made of a third metal material that is metallurgically compatible with the molybdenum reflector 1 and the molybdenum rotor assembly 2. The intermediate layer 3 has higher plasticity at room temperature and higher affinity for impurity atoms in the interface region between the three than the molybdenum material. During heating and cooling, it absorbs and releases thermal stress and shrinkage stress from the molybdenum materials on both sides through its own plastic deformation, and reacts with impurity atoms before the molybdenum material, thereby inhibiting the initiation and propagation of cracks in the recrystallization zone of the molybdenum material or at the weld. For the specific connection method between the three components, please refer to specific embodiments 1 to 4. Detailed Implementation Method 1

[0054] Please see Figure 2 and Figure 3 The intermediate layer 3 has a cylindrical structure and is screwed to the molybdenum rotor assembly 2. The molybdenum reflector 1 is screwed to the intermediate layer 3. The intermediate layer 3 is connected to the molybdenum rotor assembly 2 and the molybdenum reflector 1 by laser welding. It can be understood that during the assembly of the anode assembly, the molybdenum rotor assembly 2, the intermediate layer 3, and the molybdenum reflector 1 are pre-assembled by threaded connections, and then finally connected by laser welding. The cylindrical structure of the intermediate layer 3 forms a circumferentially continuous, large-area mating surface between the molybdenum reflector 1 and the molybdenum rotor assembly 2, providing stable circumferential support for the molybdenum reflector 1, effectively suppressing micro-vibrations or deformations under high-speed rotation, and improving the dynamic stability of the structure.

[0055] The intermediate layer 3 is preferably made of titanium, which has a coefficient of thermal expansion of approximately 8.6 μm / m·K, while molybdenum has a coefficient of thermal expansion of approximately 4.8 μm / m·K. The absolute value of the difference between the two is no greater than 5.0 μm / m·K, which helps to reduce the additional thermal stress caused by uneven expansion and contraction during heating and cooling. Furthermore, molybdenum and titanium are partially miscible in the liquid state. At the welding interface, molybdenum and titanium will interdiffusion to form a solid solution with strength and toughness between molybdenum and titanium, thus providing a good performance gradient, avoiding abrupt changes in performance, and improving the bonding performance between molybdenum and titanium.

[0056] Compared to molybdenum, titanium has a stronger affinity for oxygen: the absolute value of the Gibbs free energy for TiO2 formation is more than twice that for MoO3 formation; and a stronger affinity for nitrogen: the absolute value of the Gibbs free energy for TiN formation is more than 10 times that for Mo2N formation. The higher the absolute value of the Gibbs free energy, the stronger the "chemical bond" between the metal and oxygen atoms. Once bonded, they can form a stable structure with extremely low energy and extremely difficult to decompose.

[0057] Of course, in some other feasible embodiments, the intermediate layer 3 can also be made of zirconium.

[0058] For materials where the absolute value of the difference between the two is greater than 5.0 μm / m·K, such as nickel, the coefficient of thermal expansion is about 13.4 μm / m·K. Molybdenum and nickel will interact violently at high temperatures to form a series of hard and brittle intermetallic compounds. These compounds lack plasticity like ceramics and are prone to becoming microcracks under welding stress, which can rapidly propagate and cause brittle fracture of the entire joint area. Furthermore, due to the large difference in their coefficients of thermal expansion, nickel shrinks much more than molybdenum during subsequent cooling, which can easily generate huge shear stress at the interface. This can easily tear the already brittle weld or compound layer, reducing the service life of the anode rotor.

[0059] Furthermore, nickel has a lower affinity for impurity atoms in the interfacial region than molybdenum, thus failing to reduce the segregation of oxygen, nitrogen, and other impurity atoms at the grain boundaries. Consequently, it cannot improve the brittleness of the recrystallization region and the weakening of high-temperature grain boundaries in molybdenum. On the contrary, the formation of brittle compounds and severe stress concentration amplify the cracking tendency of the heat-affected zone of the molybdenum base material.

[0060] The specific processing steps are as follows:

[0061] After ultrasonic cleaning with alcohol or pure water, the molybdenum rotor assembly 2, intermediate layer 3, and molybdenum reflector 1 are degassed at high temperature in a vacuum furnace at 400 to 700°C. After degassed, the intermediate layer 3 is threaded onto the molybdenum rotor assembly 2, and the molybdenum reflector 1 is then threaded onto the intermediate layer 3, forming a "molybdenum-titanium-molybdenum" sandwich structure. The components are then placed on a laser welding table for laser processing and fixation. The position of the protective gas nozzle is adjusted to blow gas onto the components for protection, ensuring that all three are in a protective atmosphere for metallurgical bonding. The protective gas used is argon gas with a purity >99.9%. The laser welding time is 0.8 to 1.2 minutes, the welding power is 100 to 200 W, the defocusing amount is 0 to 0.2 mm, and the weld type is butt welding. Detailed Implementation Method 2

[0063] The difference from Specific Implementation Method 1 lies in the method of pre-assembly.

[0064] Specifically, please refer to Figure 4 and Figure 5The molybdenum reflector 1 is screwed onto the molybdenum rotor assembly 2, and the molybdenum reflector 1 and the molybdenum rotor assembly 2 form a receiving groove for accommodating the intermediate layer 3. It is understood that during pre-assembly, the molybdenum reflector 1 is directly screwed onto the molybdenum rotor assembly 2, and then the intermediate layer 3 is directly inserted into the receiving groove between the molybdenum rotor assembly 2 and the molybdenum reflector 1, and then connected to the molybdenum rotor assembly 2 and the molybdenum reflector 1 by laser welding; wherein, the intermediate layer 3 is a cylindrical structure made of titanium or zirconium that conforms to the shape of the receiving groove.

[0065] It should be noted that, except for pre-assembly, the other steps in the specific processing steps in this embodiment are the same as those in Specific Embodiment 1, and will not be described in detail here. Detailed Implementation Method 3

[0067] The difference from Specific Implementation Method 2 lies in the choice of material for the intermediate layer 3 and the welding method.

[0068] Specifically, please refer to Figure 4 and Figure 5 The intermediate layer 3 is made of liquid brazing filler metal. After the molybdenum reflector sheet 1 is screwed to the molybdenum rotor assembly 2, the liquid brazing filler metal is filled into the receiving groove and then brazed to the molybdenum rotor assembly 2 and the molybdenum reflector sheet 1. It is understood that the regular receiving groove provides a continuous and complete flow channel for the liquid brazing filler metal, allowing it to uniformly fill the connection interface between the molybdenum rotor assembly 2 and the molybdenum reflector sheet 1, preventing defects such as incomplete filling or porosity, and achieving a full-contact area metallurgical bond among the three components. The liquid brazing filler metal is preferably palladium-based, such as Pd-Ni, Pd-Co, or Pd-Cu, which has good wettability, effectively dissolves oxides on the molybdenum surface, and forms a joint with high strength, good ductility, and few brittle phases.

[0069] Nickel-based solders, such as BNi-5, BNi-7, and pure nickel foil, are prone to forming brittle intermetallic compounds (such as NiMo and Ni4Mo) with molybdenum, which can cause the joint to crack easily at room temperature or under thermal cycling.

[0070] It should be noted that molybdenum readily forms a stable oxide film, namely molybdenum trioxide, at high temperatures. This causes the liquid brazing filler metal to clump together in a spherical shape on the oxide film surface, similar to water droplets on a lotus leaf (contact angle >90°). Consequently, the liquid brazing filler metal cannot spread evenly within the receiving groove, meaning an effective brazing joint cannot be formed. Normal brazing involves a small amount of mutual dissolution and diffusion between the filler metal and the base material, forming a strong metallurgical bond (metallic bond). However, the formation of the oxide film is equivalent to creating a physical and chemical "barrier" between the two, reducing the connection strength between the molybdenum reflector 1 and the molybdenum rotor assembly 2, making it prone to peeling off from the interface under stress or thermal cycling.

[0071] Therefore, during brazing, all three components must be placed in a vacuum environment, such as 10... -3 Pa or higher, preferably 5×10 Pa -4 Pa, under high vacuum conditions, can sublimate and remove existing molybdenum trioxide to prevent the formation of new oxide films.

[0072] In some other feasible embodiments, the three can also be placed in an ultra-high purity dry reducing atmosphere, such as pure hydrogen with a dew point <-40°C, where hydrogen can reduce molybdenum trioxide to molybdenum and water, thereby preventing the formation of molybdenum trioxide.

[0073] The specific processing steps are as follows:

[0074] The anode assembly, pre-assembled with palladium-based brazing filler metal via threading, is placed in a vacuum brazing furnace. The vacuum system is then activated, evacuating the furnace chamber to a basic high vacuum, such as 5 × 10⁻⁶. -4 Pa, heating the anode assembly to 800°C at a heating rate of 10°C / min to 15°C / min and holding for a preset time. This temperature is lower than the melting temperature of the palladium-based solder, but sufficient to allow the moisture, grease and other contaminants adsorbed on the surface and inside of the anode assembly to fully volatilize and decompose, and be removed by the vacuum system. The preset time depends on the size and loading of the anode assembly to ensure thorough degassing.

[0075] The temperature was then increased from 800°C to 1260°C ± 10°C. At this temperature, the palladium-based solder melted into a liquid state and was held for 10 to 20 minutes to ensure that the liquid solder filled every corner of the entire containment tank. Furthermore, the high temperature allowed the solder and any trace gases dissolved within the interface to escape further, reducing weld porosity.

[0076] After heating is complete, the temperature is reduced to below 900°C at a rate of 5°C / min to 10°C / min to avoid excessive internal stress or even cracks in molybdenum (a brittle material) and brazing seams due to uneven shrinkage caused by excessively rapid cooling. After cooling to below 900°C, the main phase transformation and stress risks have passed, and the furnace can be switched to in-furnace cooling (natural cooling after power failure) to near room temperature. Detailed Implementation Method 4

[0078] Similar to specific implementation methods 1 and 2, the material of the intermediate layer 3 is the same. The difference is that the shape of the intermediate layer 3 is different, and the connection method and welding method are also different.

[0079] Specifically, please refer to Figure 6 and Figure 7The molybdenum reflector 1 is screwed to the molybdenum rotor assembly 2. The intermediate layer 3 is a columnar structure that penetrates the molybdenum reflector 1 and is embedded in the molybdenum rotor assembly 2. It is also connected to the molybdenum rotor assembly 2 and the molybdenum reflector 1 by argon arc welding. It is understood that the columnar intermediate layer 3 forms a mechanical interlocking structure similar to a rivet between the molybdenum reflector 1 and the molybdenum rotor assembly 2. This effectively resists the centrifugal and tangential forces experienced by the molybdenum reflector 1 during high-speed rotation, preventing relative slippage at the interface and thus improving the service life of the anode assembly.

[0080] The specific processing steps are as follows:

[0081] The molybdenum rotor assembly 2 is screwed to the molybdenum reflector 1, and the pre-drilled holes on the molybdenum rotor assembly 2 and the molybdenum reflector 1 are aligned to form a receiving groove. The intermediate layer 3, such as a titanium nail that is adapted to the receiving groove, is pressed into the receiving groove to complete the pre-assembly of the anode assembly. Then, the anode assembly is placed in the welding fixture, and the welding position is ensured to be located at the junction of the gap between the molybdenum reflector 1 and the molybdenum rotor assembly 2 and the titanium nail, and the tungsten needle of the welding gun is positioned close to the titanium nail.

[0082] Set the welding parameters as follows: welding current 120-130A, welding voltage 12-16V, welding time 0.1-0.3s. One second before welding, supply high-purity argon shielding gas at a flow rate of 10-15L / min, ensuring the argon purity is ≥99.9%. This purges and displaces air from the weld area and around the titanium nails, establishing a pure argon shielding zone to prevent oxidation during arc ignition. Stop supplying argon shielding gas two seconds after welding.

[0083] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method for processing an anode assembly, characterized in that, Includes the following steps: S1: Provides a molybdenum reflector (1) and a molybdenum rotor assembly (2); S2: Provide an intermediate layer (3) made of a third metal material that is metallurgically compatible with the molybdenum reflector (1) and the molybdenum rotor assembly (2); S3: The intermediate layer (3) is disposed between the molybdenum reflector (1) and the molybdenum rotor assembly (2); S4: In a protective atmosphere or vacuum environment, the connection area of ​​the molybdenum reflective sheet (1), the intermediate layer (3) and the molybdenum rotor assembly (2) is heated so that the three are combined by metallurgical means. The intermediate layer (3) has higher plasticity at room temperature and higher affinity for impurity atoms in the interface region between the three materials than the molybdenum material. During heating and cooling, it absorbs and releases thermal stress and shrinkage stress from the molybdenum materials on both sides through its own plastic deformation, and reacts with the impurity atoms before the molybdenum material, thereby inhibiting the initiation and propagation of cracks in the recrystallization zone of the molybdenum material or at the weld.

2. The anode component processing method according to claim 1, characterized in that, The metal material is titanium, zirconium, or liquid brazing filler metal.

3. The anode component processing method according to claim 1, characterized in that, The metallurgical method is laser welding, argon arc welding, or brazing.

4. The anode component processing method according to claim 1, characterized in that, The absolute value of the difference between the thermal expansion coefficient of the metal material and the thermal expansion coefficient of the molybdenum material is no greater than 5.0 μm / m·K.

5. The anode assembly processing method according to claim 1, characterized in that, In S4, before heating the molybdenum reflector (1), the intermediate layer (3) and the molybdenum rotor assembly (2), the molybdenum reflector (1), the molybdenum rotor assembly (2) and the metal intermediate layer (3) need to be ultrasonically cleaned and degassed at high temperature using a vacuum furnace.

6. An anode assembly, characterized in that, The system includes a molybdenum reflector (1), a molybdenum rotor assembly (2), and an intermediate layer (3). The intermediate layer (3) is disposed between the molybdenum reflector (1) and the molybdenum rotor assembly (2). The intermediate layer (3) is made of a third metal material that is metallurgically compatible with the molybdenum reflector (1) and the molybdenum rotor assembly (2). The intermediate layer (3) has higher plasticity at room temperature and higher affinity for impurity atoms in the interface region between the three than the molybdenum material. During heating and cooling, it absorbs and releases thermal stress and shrinkage stress from the molybdenum materials on both sides through its own plastic deformation. It reacts with the impurity atoms before the molybdenum material, thereby inhibiting the initiation and propagation of cracks in the recrystallization zone of the molybdenum material or at the weld.

7. The anode assembly according to claim 6, characterized in that, The intermediate layer (3) is a cylindrical structure, and the intermediate layer (3) is screwed to the molybdenum rotor assembly (2). The molybdenum reflector (1) is screwed to the intermediate layer (3). The intermediate layer (3) is connected to the molybdenum rotor assembly (2) and the molybdenum reflector (1) by laser welding.

8. The anode assembly according to claim 6, characterized in that, The molybdenum reflector (1) is screwed to the molybdenum rotor assembly (2), and the molybdenum reflector (1) and the molybdenum rotor assembly (2) form a receiving groove for accommodating the intermediate layer (3).

9. The anode assembly according to claim 8, characterized in that, The intermediate layer (3) is made of titanium or zirconium, which forms a cylindrical structure that conforms to the shape of the receiving groove, and is connected to the molybdenum rotor assembly (2) and the molybdenum reflector (1) by laser welding; or; The intermediate layer (3) is made of liquid brazing filler metal, which fills the receiving groove and is connected to the molybdenum rotor assembly (2) and the molybdenum reflector (1) by brazing.

10. The anode assembly according to claim 6, characterized in that, The molybdenum reflector (1) is screwed to the molybdenum rotor assembly (2). The intermediate layer (3) is a columnar structure that penetrates the molybdenum reflector (1) and is embedded in the molybdenum rotor assembly (2). It is also connected to the molybdenum rotor assembly (2) and the molybdenum reflector (1) by argon arc welding.

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