Motor rotor and processing method thereof

Abstract

The invention relates to the technical field of motor rotors, and discloses a motor rotor and a machining method thereof.The method comprises the steps that hot forging is conducted on an alloy steel base material based on the preset forging and pressing temperature, and multi-layer gradient cutting is conducted on a rotor initial blank; the method comprises the following steps: performing composite deposition treatment on a cylindrical blank based on a magnetic material, placing the magnetic composite blank in a vacuum environment for dynamic heat treatment, performing dynamic balance finishing on the heat treatment blank based on a preset alloy, performing surface strengthening treatment on a balance rotor in a nitrogen atmosphere, and coating the balance rotor subjected to surface strengthening with a preset coating, the motor rotor with the optimized surface is obtained; and dynamic balance trimming is combined with preset alloy characteristics for microstructure regulation and control, and it is ensured that the rotor has excellent operation stability in a high-rotation-speed environment. And finally, surface strengthening treatment is carried out in a nitrogen atmosphere, and a functional coating is used for covering, so that the wear resistance and corrosion resistance of the surface layer are remarkably improved, and the requirements of a motor system on a high-performance rotor under complex working conditions are met.

Description

Technical Field

[0001] The present invention relates to the technical field of motor rotors, and more specifically, to a motor rotor and a processing method thereof. Background Art

[0002] With the continuous development of industrial automation and intelligent manufacturing, the motor, as the core power source of various electromechanical devices, directly affects the operating efficiency and stability of the entire device. As a key component of the motor, the structural design and processing technology of the motor rotor play a crucial role in ensuring the efficient operation of the motor, reducing energy consumption, and extending its service life. Currently, the manufacturing process of motor rotors is gradually evolving towards high precision, high performance, and high reliability. Especially in the fields of new energy vehicles, aerospace, and high-end manufacturing equipment, higher requirements are put forward for the performance of motor rotors.

[0003] In the prior art, the processing of motor rotors usually prepares the initial blank by directly cooling after single-temperature forging, and then performs mechanical cutting and single heat treatment, and finally completes the surface treatment. This leads to uneven grain distribution inside the material during the cooling process, which in turn affects the dynamic balance performance of the rotor. Especially in application scenarios with high rotational speeds or large load changes, the unevenness may cause vibration amplification during rotor operation, reduce the motor efficiency, and even shorten the service life.

[0004] Therefore, it is necessary to provide a motor rotor and a processing method thereof to solve the problem of poor dynamic balance performance of existing motor rotors. Summary of the Invention

[0005] The main object of the present invention is to provide a motor rotor and a processing method thereof, aiming to solve the technical problems mentioned in the above background art.

[0006] The present invention adopts the following technical solutions: A motor rotor and a processing method thereof, comprising: Hot forging the alloy steel substrate based on a preset forging temperature, and performing gradient cooling treatment on the hot-forged alloy steel substrate to obtain a rotor initial blank; Performing multi-layer gradient cutting on the rotor initial blank to obtain a cylindrical blank; Performing composite deposition treatment on the cylindrical blank based on magnetic materials to obtain a magnetic composite blank; Placing the magnetic composite blank in a vacuum environment for dynamic heat treatment to obtain a heat-treated blank; Performing dynamic balance trimming on the heat-treated blank based on a preset alloy to obtain a balanced rotor; The surface of the balance rotor is strengthened under a nitrogen atmosphere, and a preset coating is applied to the surface-strengthened balance rotor to obtain a motor rotor with an optimized surface.

[0007] Further, the alloy steel substrate is a mixture of chromium, molybdenum, carbon, nickel, vanadium and iron elements. Among them, in the alloy steel substrate, calculated by mass percentage, the proportion of chromium is 1.5 - 3%, the proportion of molybdenum is 0.5 - 1.2%, the proportion of carbon is 0.3 - 0.6%, the proportion of nickel is 0.8 - 1.5%, the proportion of vanadium is 0.1 - 0.25%, and the balance is iron.

[0008] Further, the step of hot forging the alloy steel substrate based on a preset forging temperature and performing gradient cooling treatment on the hot-forged alloy steel substrate to obtain a rotor blank includes: Under an inert gas atmosphere, the alloy steel substrate is heated to 900 - 950 °C for preheating to obtain a preheated substrate; The preheated substrate is subjected to multi-directional hot forging at a forging frequency of 12 - 18 times per minute and an extrusion angle of 30° - 45° to obtain a primary forging blank; The primary forging blank is placed in an environment of 700 - 800 °C for 2 hours of heat preservation, and then cold air is sprayed on the outer surface of the primary forging blank to cool it down to 650 °C to form an annealed blank; The annealed blank is cooled down to 450 °C at a rate of 4 °C per minute through a circulating liquid cooling system, and then argon is sprayed on the annealed blank at a preset spraying angle for auxiliary cooling to room temperature to obtain a pre-cooled blank; The pre-cooled blank is tempered at 300 - 350 °C for 2 hours, and based on a nitrogen circulation system, the tempered pre-cooled blank is cooled down to 150 °C to obtain a fine-tuned blank; The fine-tuned blank is cooled down to 80 °C at a rate of 1.5 °C per minute, and then the fine-tuned blank is naturally cooled to room temperature to obtain a rotor blank.

[0009] Further, the step of performing multi-layer gradient cutting on the rotor blank to obtain a cylindrical blank includes: The rotor blank is fixed and preheated to 200 °C, and the outer surface of the preheated rotor blank is rough cut by 3 - 5 mm at a rotational speed of 600 revolutions per minute to obtain a rough machined blank; The rough machined blank is subjected to layered peeling cutting to obtain a layered blank, and based on ultrasonic assistance, the layered blank is precisely cut at a frequency of 30 kHz to obtain a precisely cut blank; The dynamic contour trimming of the precision-cut blank is carried out based on a three-coordinate measuring instrument to obtain a trimmed blank. Subsequently, the trimmed blank is tempered at 150 °C for 2 hours, and the trimmed blank is cut to the target size based on a precision lathe with a cutting depth of 0.3 - 0.5 mm to obtain a preformed blank; The outer surface of the preformed blank is polished and cut at a preset polishing speed to obtain a cylindrical blank.

[0010] Further, the step of performing composite deposition treatment on the cylindrical blank based on a magnetic material to obtain a magnetic composite blank includes: Based on a plasma cleaning device, in the working gas pressure, the cylindrical blank is bombarded by plasma to obtain an activated blank; The activated blank is subjected to ion carburizing treatment in a mixed gas atmosphere of methane and nitrogen to obtain a carburized blank; Based on a high-frequency plasma arc, a magnetic material is sprayed on the carburized blank to obtain a primary magnetic blank, and in the working gas pressure, the primary magnetic blank is subjected to hot pressing and curing treatment to obtain a cured magnetic blank; The cured magnetic blank is subjected to magnetic field orientation optimization treatment to obtain an oriented magnetic blank, and the surface of the oriented magnetic blank is subjected to plasma polishing treatment using a mixed gas of argon and oxygen as a polishing medium to obtain a magnetic composite blank.

[0011] Further, the step of placing the magnetic composite blank in a vacuum environment for dynamic heat treatment to obtain a heat-treated blank includes: In the working gas pressure, first, the magnetic composite blank is heated to 600 °C at a heating rate of 8 °C / min and held for 1.5 hours, then it is raised to 900 °C at a heating rate of 12 °C / min and held for 2 hours to obtain a strengthened blank with an enhanced magnetic layer; The strengthened blank is cooled to 700 °C at a rate of 5 °C / min and held for 1 hour, then cooled to 550 °C at a rate of 3 °C / min and held for 2 hours, and then cooled to 400 °C at a rate of 2 °C / min and held for 1.5 hours to obtain a lattice-optimized blank; A constant magnetic field of 0.5 Tesla is applied to the lattice-optimized blank, and at the same time, the temperature is raised from 400 °C to 650 °C at a rate of 5 °C / min and held for 1 hour, and then cooled to 300 °C at a rate of 4 °C / min to obtain a magnetically optimized blank; In an inert gas atmosphere, the magnetically optimized blank is cooled to 150 °C at a rate of 2 °C / min and held for 2.5 hours to obtain a stable blank; Cool the stable blank to room temperature at a rate of 1.5 °C per minute, and pause for 10 minutes every 50 °C drop during the cooling process to obtain a heat-treated blank.

[0012] Further, the step of performing dynamic balance trimming on the heat-treated blank based on a preset alloy to obtain a balanced rotor includes: Perform an initial rotation test on the heat-treated blank based on a dynamic balance detection platform to obtain the initial vibration distribution characteristics of the heat-treated blank; Deconstruct the initial vibration distribution characteristics through Fourier transform and vector decomposition, calculate and mark the eccentric area of the heat-treated blank to obtain a positioned blank; Based on a plasma spraying device, locally pre-deposit cobalt-based alloy powder on the positioned blank to obtain a pre-trimmed blank; Heat the pre-trimmed blank to 600 °C at a rate of 5 °C per minute and hold for 20 minutes, and apply vibration with a frequency of 40 kHz to the pre-trimmed blank during the heating process to obtain a fine-tuned blank; Perform a secondary balance verification on the fine-tuned blank based on a dynamic balance detection platform, compare and analyze the verification result with the initial vibration distribution characteristics, and generate a residual eccentricity distribution map; According to the residual eccentricity distribution map, locally deposit nickel-based alloy on the fine-tuned blank through electron beam welding to obtain a dynamically balanced rotor.

[0013] Further, the step of performing surface strengthening treatment on the balanced rotor in a nitrogen atmosphere and coating the surface-strengthened balanced rotor with a preset coating to obtain a surface-optimized motor rotor includes: Perform ion nitriding treatment on the balanced rotor in a nitrogen atmosphere to obtain a nitrided rotor; Immerse the nitrided rotor in a composite electrolyte for micro-arc oxidation treatment to obtain an oxidation-strengthened rotor. The composite electrolyte contains silicate, phosphate and alumina powder, where the concentration of silicate is 20 g / L, the concentration of phosphate is 30 g / L, the concentration of alumina powder is 50 g / L, the voltage of the micro-arc oxidation treatment is 450 V, the current density is 8 A / dm², and the oxidation time is 40 minutes; Based on a plasma spraying device, perform ceramic coating deposition treatment on the oxidation-strengthened rotor with a preset coating raw material, where the preset coating raw material includes a mixture of alumina and zirconia powder to obtain a composite coating rotor; Perform laser remelting treatment on the surface of the composite coating rotor to obtain a remelting-strengthened rotor, and perform metal film deposition on the remelting-strengthened rotor using a high-purity titanium target as a deposition source to obtain a film layer-optimized rotor; The optimized rotor of the film layer is coated by low-temperature curing with a fluorine-containing polyurethane preset coating to obtain a motor rotor with an optimized surface.

[0014] A motor rotor, adopting the processing method of the above motor rotor, includes a shaft body and a core body. The core body is sleeved outside the shaft body. The shaft body is axially provided with an elliptical fixing groove, and the core body is fixedly connected to the shaft body through the fixing groove; The outer surface of the core body is coated with a magnetic composite layer. A plurality of magnetic pole units are embedded along the circumferential direction on the outer surface of the magnetic composite layer. The cross-section of the magnetic pole unit is trapezoidal, and a separation strip is arranged between two adjacent magnetic pole units.

[0015] Further, balance strengthening rings are arranged at opposite ends of the core body. A plurality of balance holes are axially formed in the balance strengthening rings, and the balance holes are coated with a weight alloy layer.

[0016] Beneficial effects: In the present invention, by performing hot forging on the alloy steel base material at a preset forging temperature and supplemented with gradient cooling treatment, the grain microstructure can be optimized while retaining the material strength, significantly improving the tissue uniformity and isotropy of the initial blank, helping to reduce the concentration of internal stress during the processing, and improving the dynamic balance basic conditions of the rotor from the source. The cylindrical blank obtained by the multi-layer gradient cutting process can achieve precise control of different structural levels, improving the geometric accuracy and surface quality of the blank. Further, the composite deposition of magnetic materials is carried out on the cylindrical blank, enabling the key magnetic functional regions to be constructed as required, enhancing the overall magnetic conductivity performance and taking into account the material lightweight requirements. By performing dynamic heat treatment in a vacuum environment and combining the coordinated control of temperature and atmosphere, the tissue defects and oxidation reactions are effectively suppressed, improving the material stability and comprehensive mechanical properties. The dynamic balance trimming combines the preset alloy characteristics for microstructure regulation to ensure that the rotor has excellent running stability in a high-speed environment. Finally, surface strengthening treatment is carried out in a nitrogen atmosphere and supplemented with a functional coating coverage, significantly improving the surface wear resistance and corrosion resistance, meeting the requirements of the motor system for high-performance rotors under complex working conditions. Description of the drawings

[0017] Figure 1 is a schematic flow chart of a processing method of a motor rotor of the present invention; Figure 2 is a schematic overall structure diagram of a motor rotor of the present invention; Figure 3 is a schematic structure diagram of the shaft body of the present invention.

[0018] Wherein: 1. Shaft body; 101. Fixing groove; 2. Core body; 3. Magnetic pole unit; 4. Balance strengthening ring; 401. Balance hole.

[0019] The realization, functional features, and advantages of the object of the present invention will be further described in conjunction with embodiments with reference to the accompanying drawings. Specific Embodiments

[0020] It should be understood that the specific embodiments described herein are merely used to explain the present invention and are not used to limit the present invention.

[0021] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless otherwise specifically defined.

[0022] In the description of the present invention, it should be noted that unless otherwise clearly defined and limited, the terms "mounted", "connected", and "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection, a direct connection, or an indirect connection through an intermediate medium, and it may be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0023] In the present invention, unless otherwise clearly defined and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features between them. Moreover, the first feature being "above", "over", and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "under", and "beneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or simply means that the horizontal height of the first feature is lower than that of the second feature.

[0024] Referring to Figure 1 , the present invention provides a motor rotor and its processing method, including: S1: Hot forge the alloy steel substrate based on a preset forging temperature, and perform gradient cooling treatment on the hot-forged alloy steel substrate to obtain a rotor blank. In step S1, place the high-strength alloy steel substrate in a multi-directional forging device, set a preset heating range according to material processing requirements, collect stress distribution data during forging through a multi-axial pressure sensor, adjust the forging frequency and extrusion angle based on the stress distribution, perform at least three rounds of repeated extrusion, record the grain size change data after each round of extrusion and iteratively optimize the forging path until the grains are refined into a uniform rod-like structure; Subsequently, transfer the forging to a cooling tank, use the temperature gradient control module to calculate the cooling rate in sections, first cool down according to a preset curve, then switch to the natural cooling mode, and adjust the cooling time based on the heat conduction simulation data to obtain a rotor blank with a uniform microstructure.

[0025] S2: Perform multi-layer gradient cutting on the rotor blank to obtain a cylindrical blank. In step S2, fix the rotor blank on a CNC lathe, determine the rough cutting path through a cutting parameter optimization algorithm, remove the surface allowance, set the cutting speed and rotational speed, record the surface profile data after each cut and dynamically adjust the tool feed rate; Subsequently, switch to the finish cutting mode, layer by layer reduce the cutting depth based on the previous rough cutting profile data, which can be set to 0.5 mm, combine with an ultrasonic detection device to collect internal defect signals, and iteratively correct the cutting trajectory based on the signal feedback until the surface roughness meets the standard to obtain a cylindrical blank with a regular shape.

[0026] S3: Perform composite deposition treatment on the cylindrical blank based on magnetic materials to obtain a magnetic composite blank. In step S3, place the cylindrical blank in a vacuum deposition furnace, use a plasma-enhanced chemical vapor deposition system, set the temperature and pressure, which can be an environment of 450 °C and 0.5 Pa, introduce a mixed gas of nitrogen and borane or other gases through a gas flow controller, dynamically adjust the gas flow ratio based on the deposition rate monitoring data to generate a magnetic layer; Subsequently, use a magnetic field orientation device to collect the initial magnetization distribution of the magnetic layer, calculate the optimal magnetic field orientation angle and apply a directional magnetic field, iteratively adjust the magnetic field strength and direction until the magnetization direction is consistent with the axis to obtain a magnetic composite blank.

[0027] S4: Place the magnetic composite blank in a vacuum environment for dynamic heat treatment to obtain a heat-treated blank. In step S4, place the magnetic composite blank in a vacuum heat treatment furnace. Set the heating rate through the temperature curve planning algorithm, which can be specifically set to 10 °C / min to 850 °C, hold for 2 hours, and adjust the holding time based on the thermal expansion data of the interface bonding state; then cool down dynamically and hold, use the cooling rate calculation module to segmentally adjust the cooling to room temperature, record the stress release data of each stage and optimize the cooling path to obtain a heat-treated blank with a stable microstructure and magnetic properties.

[0028] S5: Perform dynamic balance trimming on the heat-treated blank based on a preset alloy to obtain a balanced rotor; In step S5, install the heat-treated blank on a dynamic balancing machine, use an eccentricity detection sensor to collect real-time vibration data, and calculate the eccentricity position and mass compensation amount based on the vibration distribution; then, based on equipment such as a laser cladding system, locally deposit a weight alloy, such as tungsten-based alloy, at the eccentric part. Set the cladding thickness to 0.1 - 0.3 mm, adjust the laser power and scanning path in combination with the heat affected zone data during the cladding process, and iteratively trim until the eccentricity is less than 0.01 g to obtain a dynamically balanced rotor.

[0029] S6: Perform surface strengthening treatment on the balanced rotor in a nitrogen atmosphere, and coat the surface-strengthened balanced rotor with a preset coating to obtain a motor rotor with optimized surface.

[0030] In step S6, place the balanced rotor in an ion nitriding furnace, introduce nitrogen at 500 °C and a gas pressure of 0.8 Pa, calculate the treatment time based on the nitriding depth prediction model to generate a nitriding layer, record the nitrogen atom diffusion data and adjust the gas pressure and time parameters; then use a low-temperature spraying device to coat a nano-ceramic coating, set the preset thickness, and optimize the nozzle movement trajectory and coating deposition rate through the spraying uniformity analysis algorithm to obtain a surface-strengthened and durable final rotor.

[0031] In summary, by performing hot forging on the alloy steel substrate at a preset forging temperature and supplemented with gradient cooling treatment, the grain structure can be optimized while retaining the material strength, significantly improving the tissue uniformity and isotropy of the initial blank, helping to reduce the concentration of internal stress during the processing, and fundamentally improving the dynamic balance basic conditions of the rotor. The cylindrical blank prepared by the multi-layer gradient cutting process can achieve precise control of different structural levels, improving the geometric accuracy and surface quality of the blank. Further, the composite deposition of magnetic materials on the cylindrical blank enables the construction of key magnetic functional regions as needed, enhancing the overall magnetic conductivity performance and taking into account the material lightweight requirements. By performing dynamic heat treatment in a vacuum environment and combining the coordinated control of temperature and atmosphere, tissue defects and oxidation reactions are effectively suppressed, improving the material stability and comprehensive mechanical properties. The dynamic balance trimming step combines the preset alloy characteristics for microstructure regulation to ensure excellent running stability of the rotor in a high-speed environment. Finally, surface strengthening treatment is carried out in a nitrogen atmosphere and supplemented with a functional coating coverage, significantly improving the surface wear resistance and corrosion resistance, meeting the requirements of the motor system for high-performance rotors under complex working conditions.

[0032] In one embodiment, the alloy steel substrate is a mixture of chromium, molybdenum, carbon, nickel, vanadium, and iron elements. Among them, in the alloy steel substrate, calculated by mass percentage, the proportion of chromium is 1.5 - 3%, the proportion of molybdenum is 0.5 - 1.2%, the proportion of carbon is 0.3 - 0.6%, the proportion of nickel is 0.8 - 1.5%, the proportion of vanadium is 0.1 - 0.25%, and the balance is iron.

[0033] In the above embodiment, the component selection of the alloy steel substrate achieves ideal mechanical properties and thermal stability by precisely proportioning the element contents. The addition of chromium can significantly improve the corrosion resistance and high-temperature strength of the steel. During hot forging and subsequent heat treatment processes, chromium enhances the grain boundary strength by forming stable carbides (such as Cr23C6), preventing excessive grain growth at high temperatures, and thus maintaining the microstructure stability of the rotor initial blank. In addition, chromium can also improve the surface strengthening effect of the substrate in a nitrogen atmosphere, promoting the bonding force between the nitrided layer and the matrix. The content is controlled within the range of 1.5 - 3%, which can not only fully exert its strengthening effect but also avoid the increase in brittleness caused by too high content, ensuring the toughness of the material under high-stress conditions.

[0034] Molybdenum helps to enhance the hardenability and thermal strength of the material. During hot forging, molybdenum enables the substrate to maintain high hardness and anti-deformation ability at high temperatures through solid solution strengthening and precipitation strengthening mechanisms. In addition, molybdenum can also improve the fatigue resistance of the material, which is crucial for the long-term stability of the motor rotor during high-speed operation. The content range is set at 0.5 - 1.2%, which can effectively improve the mechanical properties while avoiding the increase in processing costs and brittleness risks caused by excessive addition.

[0035] As the main hardening element in steel, carbon is crucial for enhancing hardness and wear resistance. Carbon significantly improves the hardness and wear resistance of the material by forming pearlite or martensite structures with iron. During the hot forging and gradient cooling stages, an appropriate carbon content helps form a fine and uniform grain structure, providing a good surface quality foundation for subsequent machining. Meanwhile, carbon can also form complex carbides with elements such as chromium and molybdenum, further enhancing the wear resistance of the material. The content range of 0.3 - 0.6% is a balance point, ensuring sufficient strength while avoiding a decrease in toughness and an increase in machining difficulty caused by excessive carbon content.

[0036] The addition of nickel can improve the low-temperature toughness and fatigue resistance of steel. Nickel dissolves in the iron matrix, improves the bonding force at grain boundaries, reduces the concentration of internal stress, which is particularly important during multi-layer gradient cutting and dynamic balance trimming processes. In addition, nickel can also enhance the corrosion resistance of the material and, in conjunction with chromium, further extend the service life of the rotor in complex environments. Controlling the content within 0.8 - 1.5% can optimize the toughness while avoiding unnecessary impacts on cost and magnetic properties due to excessive addition.

[0037] Vanadium further improves the strength and toughness of steel by refining grains. Vanadium forms fine VC carbide particles, which can significantly refine grains and improve the strength and fatigue resistance of the material. During the hot forging and dynamic heat treatment stages, the precipitation strengthening effect of vanadium helps inhibit grain growth, ensuring the microstructural uniformity of the rotor billet and heat-treated billet. The content range of 0.1 - 0.25% can fully exert its grain-refining effect while avoiding carbide segregation caused by excessive addition.

[0038] Iron, as the remaining component of the base material, constitutes the main framework of the alloy steel. Iron provides a good foundation for machining performance and magnetic permeability, and works in synergy with other alloying elements to form a base material with balanced properties. By precisely controlling the proportions of various elements, iron-based alloy steel can exhibit excellent adaptability in processes such as hot forging, deposition, and surface strengthening. Optimizing the alloy composition can not only meet the requirements of the motor rotor for high strength, high toughness, and good thermal stability but also lay a solid foundation for subsequent processing, ensuring that the final product has excellent dynamic balance and durability under high-speed and high-load conditions.

[0039] In one example, the step of hot forging the alloy steel base material based on a preset forging temperature and subjecting the hot-forged alloy steel base material to gradient cooling treatment to obtain a rotor billet includes: Heating the alloy steel base material to 900 - 950 °C for preheating in an inert gas atmosphere to obtain a preheated base material; Performing multi-directional hot forging on the preheated base material at a forging frequency of 12 - 18 times per minute and an extrusion angle of 30° - 45° to obtain a preliminary forged billet; Place the initial forging blank in an environment of 700 - 800 °C and keep it warm for 2 hours. Subsequently, spray cold air on the outer surface of the initial forging blank to cool it down to 650 °C, forming an annealed blank. Cool the annealed blank to 450 °C at a rate of 4 °C per minute through a circulating liquid cooling system. Subsequently, spray argon on the annealed blank at a preset spraying angle for auxiliary cooling to room temperature, obtaining a pre-cooled blank. Perform tempering treatment on the pre-cooled blank at 300 - 350 °C for 2 hours, and based on the nitrogen circulation system, cool the tempered pre-cooled blank to 150 °C, obtaining a finely adjusted blank. Cool the finely adjusted blank to 80 °C at a rate of 1.5 °C per minute, and then naturally cool the finely adjusted blank to room temperature, obtaining a rotor initial blank.

[0040] In the above embodiment, place the high-strength alloy steel substrate in a multi-stage heating furnace, and gradually raise the temperature to the preset forging range of 900 - 950 °C through a zoning temperature control system. Use an infrared thermometer to monitor the temperature distribution on the surface and in the core of the substrate in real time, ensure that the temperature difference is controlled within ±5 °C, and at the same time inject argon through an inert gas circulation system to maintain a low-oxygen environment and avoid surface oxidation, obtaining a preheated substrate with uniform temperature.

[0041] Transfer the preheated substrate to a multi-directional forging device, set the forging temperature to 950 - 1000 °C, apply periodic pressure through a multi-axial servo hydraulic system, collect stress distribution data during forging using a three-dimensional stress sensor, dynamically adjust the forging frequency to 12 - 18 times per minute and the extrusion angle range between 30° and 45° according to the stress distribution, perform five rounds of progressive extrusion, and observe the grain morphology through a microscope and optimize the forging path after each round of extrusion until the grains are refined into a uniform rod-like structure, obtaining an initial forging blank.

[0042] Place the initial forging blank in a vacuum annealing furnace, set the annealing temperature to 700 - 800 °C, monitor the change of the internal temperature field of the blank through a thermocouple array, use gradient heating technology to control the temperature of the surface and core of the blank in zones, introduce a small amount of nitrogen during the annealing process to adjust the surface tissue characteristics, set the holding time to 2 hours, and then cool the temperature to 650 °C through an inert gas spraying system, obtaining an annealed blank with stress released.

[0043] Transfer the annealed blank to a multi-stage cooling tank, use a temperature gradient control module to set cooling parameters in zones according to the thickness and heat conduction characteristics of the blank. First, cool the temperature to 450 °C at a rate of 4 °C / min through a circulating water cooling system, and then switch to the high-pressure argon spraying mode to assist in cooling the core of the blank. Monitor the temperature distribution through a thermal imager during the cooling process and adjust the air flow intensity and spraying angle, obtaining a pre-cooled blank with balanced temperature.

[0044] Place the pre-cooled blank in a precision heat treatment furnace, set the tempering temperature to 300 - 350 °C, use the electromagnetic induction heating system to heat the blank in a zonal pulsed manner, detect the surface temperature change with a laser thermometer, dynamically adjust the heating power and holding time to 2 hours according to the temperature data to stabilize the microstructure, and then use the low-temperature nitrogen circulation system to cool the temperature to 150 °C to obtain a fine-tuned blank with a stable structure.

[0045] Place the fine-tuned blank in a programmed cooling device, set a two-stage cooling curve through a multi-channel temperature control system. First, cool the temperature to 80 °C at a rate of 1.5 °C / min, then switch to the natural cooling mode, use a thermal conductivity analyzer to collect the internal heat flow data of the blank in real time, and adjust the air volume and humidity of the cooling environment according to the data to ensure no micro-cracks on the surface. Finally, complete the cooling at room temperature to obtain a rotor preform with a uniform microstructure.

[0046] In one example, the step of performing multi-layer gradient cutting on the rotor preform to obtain a cylindrical blank includes: Fix the rotor preform and preheat it to 200 °C, and perform rough cutting of 3 - 5 mm on the outer surface of the preheated rotor preform at a rotational speed of 600 revolutions per minute to obtain a rough machined blank; Perform layer-by-layer peeling cutting on the rough machined blank to obtain a layered blank, and perform precision cutting on the layered blank at a frequency of 30 kHz based on ultrasonic assistance to obtain a precision cut blank; Perform dynamic contour trimming on the precision cut blank based on a coordinate measuring machine to obtain a trimmed blank. Then, temper the trimmed blank at 150 °C for 2 hours, and perform cutting on the trimmed blank to the target size with a cutting depth of 0.3 - 0.5 mm based on a precision lathe to obtain a preformed blank; Perform polishing cutting on the outer surface of the preformed blank at a preset polishing rotational speed to obtain a cylindrical blank.

[0047] In the above embodiment, place the rotor preform in a special fixture, preheat it to 200 °C at a high temperature to release the internal stress, and then use a cemented carbide tool to perform the first rough cutting on its outer surface to remove the 3 - 5 mm thick oxide layer and irregular protrusions on the surface. During the cutting process, set the rotational speed to 600 revolutions per minute in a low-speed rotation mode, and at the same time, cooperate with high-pressure coolant spraying to cool down and wash away the chips to ensure the initial flatness of the cutting surface and obtain a rough machined blank.

[0048] Fix the rough-formed blank on a multi-axis linkage lathe, and use the stepped cutting process to perform layered peeling cutting on its outer surface. The cutting depth for each time is controlled within 1 - 2 mm, and it gradually decreases layer by layer from the outside to the inside until it approaches the core area. During cutting, manually adjust the tool angle and combine with intermittent shutdown to check the surface flatness to ensure that there are no obvious cracks or thermal deformation marks after each layer of cutting, and obtain a layered blank with a preliminary regular shape. Install the layered blank in an ultrasonic vibration cutting device, drive the tool to vibrate at a frequency of 30 kHz with the help of an ultrasonic generator, and perform precision cutting on its surface. The cutting depth gradually decreases to 0.8 mm. At the same time, introduce a low-temperature nitrogen gas flow during the cutting process to reduce the frictional heat effect. Through multiple cycles of cutting and observing the change of surface gloss in real time until there are no obvious machining marks on the surface, obtain a precision-cut blank with higher dimensional accuracy.

[0049] Place the precision-cut blank in a three-coordinate measuring instrument to detect its outer contour geometry, and use the detection results to guide the trimming process. Dynamically trim the surface of the precision-cut blank with a micro-grinding wheel. When trimming, adjust the grinding wheel speed and feed rate according to the contour deviation in different areas, and focus on grinding the local convex or concave areas multiple times until the overall contour error is controlled within 0.05 mm, and obtain a trimmed blank with a consistent outer shape.

[0050] Place the trimmed blank in a low-temperature tempering furnace and keep it at 150 °C for 2 hours to eliminate residual stress. Then quickly transfer it to a precision lathe for low-temperature cutting treatment. During cutting, use liquid nitrogen to cool the tool and the workpiece to maintain material stability. The cutting depth is controlled within 0.3 - 0.5 mm. Gradually approach the target size through multi-directional rotary cutting to ensure that the cutting surface is smooth and has no micro-cracks, and obtain a preformed blank close to a cylindrical shape.

[0051] Fix the preformed blank in a high-speed polishing machine, and use a diamond-coated tool to perform polishing cutting treatment on its surface. When polishing, set the rotation speed to 1200 revolutions per minute and gradually increase it to 1500 revolutions per minute. At the same time, spray fine-particle grinding fluid to enhance the surface finish. Through multiple progressive polishing and combining with optical microscope to check the surface roughness until the surface reaches a mirror effect and the dimensions fully meet the design requirements, and obtain the final cylindrical blank.

[0052] In one example, the step of performing composite deposition treatment on the cylindrical blank based on magnetic materials to obtain a magnetic composite blank includes: Based on a plasma cleaning device, in the working air pressure, bombard the cylindrical blank with plasma to obtain an activated blank; Perform ion carburizing treatment on the activated blank in a mixed gas atmosphere of methane and nitrogen to obtain a carburized blank; Spray a magnetic material on the carburized blank based on a high-frequency plasma arc to obtain a primary magnetic blank, and perform hot pressing and curing treatment on the primary magnetic blank at the working air pressure of to obtain a cured magnetic blank; Perform magnetic field orientation optimization treatment on the cured magnetic blank to obtain an oriented magnetic blank, and perform plasma polishing treatment on the surface of the oriented magnetic blank using a mixed gas of argon and oxygen as a polishing medium to obtain a magnetic composite blank.

[0053] In the above embodiment, place the cylindrical blank in a plasma cleaning device, set the working air pressure to 0.3 Pa, use a mixed gas of argon and hydrogen as a plasma source, generate high-energy plasma by exciting through a radio frequency power supply, bombard the surface of the cylindrical blank to remove the surface oxide layer and microscopic impurities, and at the same time, by controlling the plasma density and treatment time, form a uniform micro-nano rough structure on the blank surface to enhance the adhesion of the subsequent deposition layer and obtain an activated blank.

[0054] Place the activated blank in an ion carburizing furnace, set the furnace temperature to 380 °C and the air pressure to 0.6 Pa, introduce a mixed gas of methane and nitrogen through a gas flow controller, and use the glow discharge technology to make carbon ions penetrate and deposit on the surface of the activated blank to form a carbide transition layer with a thickness of 0.2 - 0.3 mm on the blank surface. At the same time, by dynamically monitoring the carburizing depth and surface hardness, adjust the discharge voltage and gas ratio to ensure that the transition layer is tightly bonded to the substrate and obtain a carburized blank.

[0055] Place the carburized blank in a plasma spraying device, use a high-frequency plasma arc as a heat source, set the spraying temperature to 500 °C, spray the pre-ground neodymium iron boron magnetic powder to the surface of the carburized blank through a carrier gas, and by controlling the spraying distance and powder supply speed, form a primary magnetic coating with a thickness of 0.5 - 0.7 mm on the surface of the carburized blank. At the same time, use a cooling system to synchronously reduce the temperature of the blank body to avoid the influence of high temperature on the substrate performance and obtain a primary magnetic blank. Place the primary magnetic blank in a vacuum hot pressing furnace, set the vacuum degree to , the temperature to 600 °C, apply a constant pressure to the primary magnetic blank through a hydraulic system, use the hot pressing effect to further fuse the primary magnetic coating and the carburized layer, and at the same time, through temperature gradient control and pressure distribution monitoring, ensure the densification of the grain structure inside the coating, eliminate micropores and stress concentration points, and obtain a cured magnetic blank.

[0056] Place the cured magnetic blank in a magnetic field orientation device, generate a uniform strong magnetic field using a superconducting coil, collect the magnetization distribution data on the surface of the cured magnetic blank in real time through a multi-channel sensor, calculate the optimal angle of the magnetic field orientation based on the collected results, then apply a directional magnetic field and gradually adjust the magnetic field strength to make the magnetic domain directions inside the magnetic coating tend to be consistent. At the same time, further optimize the magnetization uniformity by rotating the blank and combining with a pulsed magnetic field to obtain a directional magnetic blank.

[0057] Place the directional magnetic blank in a plasma polishing device, set the air pressure to 0.4 Pa, use a mixed gas of argon and oxygen as the polishing medium, and perform fine polishing on the surface of the directional magnetic blank through the action of high-energy particles of the plasma to remove surface micro-protrusions and deposition defects. At the same time, by controlling the polishing time and plasma energy, make the surface of the magnetic coating reach mirror-level flatness, and finally obtain a magnetic composite blank.

[0058] In one example, the step of placing the magnetic composite blank in a vacuum environment for dynamic heat treatment to obtain a heat-treated blank includes: At the working air pressure, first heat the magnetic composite blank to 600 °C at a heating rate of 8 °C per minute and hold for 1.5 hours, then increase the temperature to 900 °C at a heating rate of 12 °C per minute and hold for 2 hours to obtain a strengthened blank with an enhanced magnetic layer; Cool the strengthened blank to 700 °C at a rate of 5 °C per minute and hold for 1 hour, then cool it to 550 °C at a rate of 3 °C per minute and hold for 2 hours, and then cool it to 400 °C at a rate of 2 °C per minute and hold for 1.5 hours to obtain a lattice-optimized blank; Apply a constant magnetic field of 0.5 Tesla to the lattice-optimized blank, and at the same time raise the temperature from 400 °C to 650 °C at a rate of 5 °C per minute and hold for 1 hour, then cool it to 300 °C at a rate of 4 °C per minute to obtain a magnetically optimized blank; Under an inert gas atmosphere, cool the magnetically optimized blank to 150 °C at a rate of 2 °C per minute and hold for 2.5 hours to obtain a stable blank; Cool the stable blank to room temperature at a rate of 1.5 °C per minute, and pause for 10 minutes every 50 °C drop during the cooling process to obtain a heat-treated blank.

[0059] In the above embodiment, place the magnetic composite blank in a vacuum heat treatment furnace, at Under the working pressure, it is gradually heated to 600 °C at a heating rate of 8 °C per minute through a precise temperature control system and held at this temperature for 1.5 hours. The vacuum environment is used to remove trace gas impurities on the surface of the blank. At the same time, the internal temperature distribution of the blank is monitored in real time through the heat conduction analysis module to ensure uniform heating of the interface between the magnetic material and the substrate, and a preheated blank with preliminary thermal stability is obtained. The preheated blank is continuously placed in a vacuum environment, and the temperature is increased from 600 °C to 900 °C at a rate of 12 °C per minute through a dynamic temperature control algorithm, held for 2 hours, and the furnace pressure is periodically adjusted to Pa during the holding process. The microscopic deformation data of the blank is detected by combining a thermal expansion monitoring device, and based on this, the holding time is optimized until the interface bonding strength reaches the peak value. Subsequently, it is cooled to 700 °C at a rate of 5 °C per minute to obtain a strengthened blank with enhanced structural stability of the magnetic layer.

[0060] The strengthened blank is placed in a vacuum furnace. Through a segmented annealing program, the temperature is first maintained at 700 °C for 1 hour, then cooled to 550 °C at a rate of 3 °C per minute and held for 2 hours, and then cooled to 400 °C at a rate of 2 °C per minute and held for 1.5 hours. The stress release monitoring system is used to record the lattice stress changes in each stage, and the cooling rate and holding time are dynamically adjusted according to the stress distribution data to obtain a lattice-optimized blank with an optimized crystal structure and uniform internal stress.

[0061] The lattice-optimized blank is placed in a vacuum environment, and a constant magnetic field of 0.5 Tesla is applied through an external magnetic field generating device. At the same time, the temperature is increased from 400 °C to 650 °C at a rate of 6 °C per minute and held for 1 hour. The molecular orientation of the magnetic material is adjusted by the synergistic action of the magnetic field and temperature, and the magnetic domain distribution state of the blank is analyzed in real time through the magnetic induction detection module. Then, it is cooled to 300 °C at a rate of 4 °C per minute to obtain a magnetically optimized blank with uniform magnetic properties and consistent orientation.

[0062] The magnetically optimized blank is placed in a vacuum furnace, and the temperature is lowered from 300 °C to 150 °C at a rate of 2 °C per minute through a low-temperature temperature control system and held for 2.5 hours. During the cooling process, a trace amount of inert gas is introduced to adjust the furnace pressure to Pa. The heat flux change of the blank is monitored by a thermal conductivity analyzer and the holding time is optimized to ensure complete release of the thermal stress at the interface between the magnetic layer and the substrate, and a stable blank with stable structure and enhanced durability is obtained.

[0063] The stabilized blank is continuously placed in a vacuum environment and cooled to room temperature at a rate of 1.5 °C per minute through a cooling path planning system. During the cooling process, the cooling rate is adjusted in segments. Specifically, for every 50 °C drop in temperature, it pauses for 10 minutes to balance the internal and external temperature differences. At the same time, a stress detection device is used to record the residual stress distribution data of the blank and optimize the cooling path. Finally, a heat-treated blank with a stable microstructure, excellent magnetic properties, and suitable for subsequent processing is obtained.

[0064] In one embodiment, the step of dynamically balancing and trimming the heat-treated blank based on a preset alloy to obtain a balanced rotor includes: Conduct an initial rotation detection of the heat-treated blank based on a dynamic balance detection platform to obtain the initial vibration distribution characteristics of the heat-treated blank; Decompose the initial vibration distribution characteristics through Fourier transform and vector decomposition, calculate the eccentric region of the heat-treated blank and mark it to obtain a positioned blank; Based on a plasma spraying device, locally pre-deposit cobalt-based alloy powder on the positioned blank to obtain a pre-trimmed blank; Heat the pre-trimmed blank to 600 °C at a rate of 5 °C per minute and hold it for 20 minutes. During the heating process, apply vibrations with a frequency of 40 kHz to the pre-trimmed blank to obtain a fine-tuned blank; Conduct a secondary balance verification of the fine-tuned blank based on a dynamic balance detection platform, compare and analyze the verification result with the initial vibration distribution characteristics, and generate a residual eccentricity distribution map; According to the residual eccentricity distribution map, locally deposit nickel-based alloy on the fine-tuned blank through electron beam welding to obtain a dynamically balanced rotor.

[0065] In the above embodiment, the heat-treated blank is fixed on a high-precision dynamic balance detection platform and rotated initially at a speed of 2500 revolutions per minute. Three-dimensional vibration signals of the blank during rotation are collected through multi-axis acceleration sensors and displacement sensors installed on the platform. The sensors record data at a frequency of 1000 times per second. Subsequently, the collected vibration signals are transmitted to an analysis system, and the initial vibration distribution characteristics of the blank are generated based on the amplitude and phase distribution of the signals to obtain the vibration distribution information of the heat-treated blank.

[0066] Place the heat-treated blank in a digital modeling system. Using the vibration distribution characteristic data, decompose the vibration signals through Fourier transform and vector decomposition techniques, calculate the specific distribution positions and eccentricity amounts of the eccentric mass of the heat-treated blank on the circumference of the blank, combine with the three-dimensional geometric model of the blank, accurately mark the eccentric regions on the surface of the blank, control the marking accuracy within 0.05 mm, and record the mass deviation values and angular coordinates of each eccentric region to obtain a positioned blank with marked eccentric regions.

[0067] Install the positioning blank on the precision CNC machining platform. For the marked eccentric area, use a plasma spraying device to locally deposit the preset cobalt-based alloy powder at a spraying speed of 0.2 millimeters per second onto the eccentric part. During the spraying process, use an infrared thermometer to monitor the temperature of the spraying area in real time, keep the temperature between 800 degrees Celsius and 850 degrees Celsius, control the deposition thickness between 0.08 millimeters and 0.15 millimeters, and then naturally cool the deposited part to room temperature to obtain a pre-machined blank with a pre-deposited alloy layer attached to its surface.

[0068] Place the pre-machined blank in a vacuum heat treatment furnace, raise the furnace temperature to 600 degrees Celsius at a heating rate of 5°C per minute, hold for 20 minutes, utilize the thermal expansion effect to cause micro-bonding between the pre-deposited cobalt-based alloy layer and the blank substrate. At the same time, apply vibrations with a frequency of 40 kHz to the blank through an ultrasonic oscillation device set inside the furnace to promote stress release and structural homogenization within the alloy layer. After cooling, conduct optical microscope inspection on the surface of the deposited layer to ensure no cracks and pores, and obtain a fine-tuned blank with a stable structure.

[0069] Reinstall the fine-tuned blank on the dynamic balancing machine, conduct a secondary rotation test at a rotational speed of 3500 revolutions per minute, collect the residual eccentricity data of the blank through a laser interferometer and a mass distribution sensor. During the detection process, record the change in eccentric mass in units of 0.01 grams. At the same time, use a high-speed camera system to capture the dynamic deformation of the blank surface, compare and analyze the collected eccentricity data with the vibration distribution data of the initial detection, and generate a residual eccentricity distribution map of the fine-tuned blank.

[0070] Fix the fine-tuned blank inside a five-axis linkage machining center. According to the residual eccentricity distribution map, use a diamond-coated milling cutter to precisely machine the residual eccentric parts on the surface of the verified blank. Control the cutting depth between 0.02 millimeters and 0.05 millimeters. During the cutting process, maintain the temperature of the machining area below 50 degrees Celsius through a coolant spraying system. Then, use an electron beam welding device to locally deposit nickel-based alloy in the machined area, with the filling thickness consistent with the cutting depth. After completion of the trimming, place the blank on the dynamic balancing machine and rotate it at 4000 revolutions per minute to confirm that the eccentricity is less than 0.005 grams, and obtain a dynamically balanced balance rotor.

[0071] In one embodiment, the step of performing surface strengthening treatment on the balance rotor in a nitrogen atmosphere and coating the surface-strengthened balance rotor with a preset coating to obtain a motor rotor with optimized surface includes: Perform ion nitriding treatment on the balance rotor in a nitrogen atmosphere to obtain a nitrided rotor; The nitrided rotor is immersed in a composite electrolyte for micro-arc oxidation treatment to obtain an oxidation-strengthened rotor. The composite electrolyte contains silicate, phosphate, and alumina powder. The concentration of silicate is 20 g / L, the concentration of phosphate is 30 g / L, and the concentration of alumina powder is 50 g / L. The voltage of the micro-arc oxidation treatment is 450 V, the current density is 8 A / dm², and the oxidation time is 40 minutes. Based on a plasma spraying device, the oxidation-strengthened rotor is subjected to ceramic coating deposition treatment using a preset coating material, and a composite coating rotor is obtained. The preset coating material includes a mixed powder of alumina and zirconia. The surface of the composite coating rotor is subjected to laser remelting treatment to obtain a remelting-strengthened rotor, and a metal film is deposited on the remelting-strengthened rotor using a high-purity titanium target as a deposition source to obtain a film layer-optimized rotor. Based on a fluorine-containing polyurethane preset coating, the film layer-optimized rotor is subjected to low-temperature curing coating to obtain a surface-optimized motor rotor.

[0072] In the above embodiment, the balanced rotor is placed in an ion nitriding furnace, and the balanced rotor is subjected to ion nitriding treatment in a nitrogen atmosphere to obtain a nitrided rotor. During the treatment, the temperature in the furnace is set to 480 °C, the air pressure is maintained at 0.7 Pa, nitrogen with a purity of 99.99% is introduced, and nitrogen atoms penetrate to the surface of the balanced rotor through ion bombardment. The nitriding time is set to 5 hours. During this period, the air pressure is dynamically adjusted according to the thermal expansion characteristics of the rotor material. The surface nitrogen atom concentration is detected every 1 hour and the diffusion depth data is recorded. Finally, a nitrided layer with a thickness of 0.06 mm is formed, and the surface of the nitrided rotor shows a uniform nitride distribution, providing a basis for subsequent strengthening.

[0073] The nitrided rotor is immersed in a composite electrolyte containing silicate, phosphate, and alumina, and the nitrided rotor is subjected to micro-arc oxidation treatment to obtain an oxidation-strengthened rotor. The concentration of silicate is 20 g / L, the concentration of phosphate is 30 g / L, and the concentration of alumina powder is 50 g / L. A pulse power supply is used during the treatment, the voltage is controlled at 450 V, the current density is set to 8 A / dm², the electrolyte temperature is maintained at 30 °C, and a dense oxidation ceramic layer is generated on the surface of the nitrided rotor through micro-arc discharge. The oxidation time lasts for 40 minutes. During this period, the pulse frequency is adjusted according to the change in the conductivity of the rotor surface to ensure that the thickness of the oxidation layer reaches 0.03 mm. The surface hardness and wear resistance of the oxidation-strengthened rotor are thus further enhanced.

[0074] Place the oxidation-strengthened rotor in a plasma spraying equipment, and conduct ceramic coating deposition treatment on the plasma spraying equipment according to the surface topography of the oxidation-strengthened rotor to obtain a composite coating rotor. During the spraying process, a mixture of alumina and zirconia powders is selected as the preset coating raw material, and the spraying is carried out in a plasma flame with a temperature controlled at 12,000 °C. The distance between the spray gun and the rotor surface is set at 100 mm, the spraying angle is dynamically adjusted according to the rotor curvature, the coating deposition time is 15 minutes, and the deposition parameters are optimized by monitoring the flame flow velocity and the melting state of the powder particles. Finally, a ceramic coating with a thickness of 0.025 mm is formed on the surface of the oxidation-strengthened rotor, and the composite coating rotor has higher heat resistance and corrosion resistance.

[0075] Place the composite coating rotor under a high-power laser equipment and conduct laser surface remelting treatment on the composite coating rotor to obtain a remelting-strengthened rotor. During the treatment, a pulsed laser with a wavelength of 1064 nm is used, the power is set at 2 kW, the laser beam moves along the rotor surface at a scanning speed of 0.5 mm / s. By precisely controlling the focal length, the laser energy is concentrated on the coating surface, causing local melting and rapid solidification of the coating. The remelting time is 10 minutes, and during this period, the laser pulse width is adjusted according to the surface reflectivity of the rotor. Finally, the microvoids in the coating are eliminated, and the surface flatness and bonding strength of the remelting-strengthened rotor are significantly optimized. Fix the remelting-strengthened rotor in a magnetron sputtering equipment, and conduct metal film deposition treatment on the magnetron sputtering equipment according to the surface characteristics of the remelting-strengthened rotor to obtain a film layer-optimized rotor. A high-purity titanium target is selected as the deposition source, the sputtering power is set at 300 W, the working gas pressure is controlled at 0.5 Pa, and reactive sputtering is carried out in a mixed atmosphere of nitrogen and argon. The deposition time is 20 minutes, and the relative position of the target and the rotor is adjusted by real-time monitoring of the film layer growth rate and the rotor surface temperature. Finally, a titanium nitride film layer with a thickness of 0.01 mm is formed on the surface of the remelting-strengthened rotor, and the surface of the film layer-optimized rotor exhibits excellent oxidation resistance and wear resistance.

[0076] Place the film layer-optimized rotor in a coating equipment and conduct low-temperature curing coating treatment on the film layer-optimized rotor to obtain a surface-optimized motor rotor. During the coating process, a fluorine-containing polyurethane preset coating is used, the spraying equipment moves along the axial direction of the rotor at a speed of 0.3 m / s, the coating thickness is controlled at 0.015 mm, and after coating, the rotor is placed in a nitrogen protection environment at 80 °C for curing treatment. The curing time is 2 hours, and during this period, the rotor surface temperature is monitored by an infrared thermometer and the ventilation rate of the curing furnace is adjusted to ensure complete bonding of the coating to the surface of the film layer-optimized rotor. Finally, a surface-optimized motor rotor with excellent weather resistance and protective performance is obtained.

[0077] Reference Figure 2 and Figure 3, the present invention also provides a motor rotor, which adopts the processing method of the motor rotor described in any one of the above, and includes a shaft body 1 and a core body 2. The core body 2 is sleeved outside the shaft body 1. The shaft body 1 is axially provided with an elliptical fixing groove 101, and the core body 2 is fixedly connected to the shaft body 1 through the fixing groove 101; The outer surface of the core body 2 is coated with a magnetic composite layer, and a plurality of pole units 3 are circumferentially embedded on the outer surface of the magnetic composite layer. The cross-section of the pole unit 3 is trapezoidal, and a spacer is provided between two adjacent pole units 3.

[0078] In the above embodiment, the core body 2 is sleeved outside the shaft body 1 to form a stable structural basis. The shaft body 1 is axially designed with an elliptical fixing groove 101. The elliptical design of the fixing groove 101 increases the contact area and geometric fit, enabling the core body 2 to be firmly fixedly connected to the shaft body 1 through the fixing groove 101, effectively preventing relative sliding during rotation, and enhancing the stability of the overall structure. The outer surface of the core body 2 is coated with a magnetic composite layer, which is made of a high magnetic permeability material and can enhance the magnetic field intensity and optimize the magnetic flux distribution. A plurality of pole units 3 are circumferentially embedded on its outer surface. The cross-section of the pole unit 3 is designed as trapezoidal, which is not only convenient for processing and installation, but also can effectively concentrate magnetic field lines and improve magnetic efficiency; the spacer provided between adjacent pole units 3 is made of a non-magnetic material and is used to reduce magnetic field interference, ensure the independent operation of each pole unit 3, and thus enhance the operating efficiency and output power of the motor.

[0079] Through the synergistic effect of the elliptical fixing groove 101 and the trapezoidal pole units 3, the mechanical strength and magnetic performance of the motor rotor are significantly improved. The elliptical design of the fixing groove 101 can evenly disperse stress when bearing high speeds, avoiding local fatigue failure; the combination of the magnetic composite layer and the trapezoidal pole units 3 optimizes the magnetic field distribution, reduces energy loss, and enables the motor to maintain excellent performance under high-load working conditions. In addition, the setting of the spacer further reduces the crosstalk between the poles, provides higher stability and durability for the motor, and is suitable for industrial scenarios requiring high-efficiency output.

[0080] In one embodiment, balance strengthening rings 4 are provided at opposite ends of the core body 2. The balance strengthening rings 4 are axially provided with a plurality of balance holes 401, and the balance holes 401 are coated with a weight alloy layer.

[0081] In the above embodiments, the balance strengthening rings 4 at the opposite ends of the core body 2 of the motor rotor are made of high-strength materials, and a plurality of balance holes 401 are axially formed. The structural performance is further optimized by coating a weight alloy layer in the balance holes 401. The main function of the balance strengthening ring 4 is to enhance the rigidity and stability of the end of the core body 2. Its ring structure can effectively resist the centrifugal force during the high-speed rotation of the rotor and prevent the end from deforming or cracking. The axially distributed balance holes 401 reduce the overall weight of the rotor and at the same time provide space for dynamic balance adjustment. The inner walls of the balance holes 401 are coated with a weight alloy layer, and an alloy material with adjustable density (such as cobalt-based or tungsten-based alloy) is used. By controlling the thickness and distribution of the coating, the mass distribution of the rotor can be precisely adjusted, significantly reducing vibration and noise during operation and improving the dynamic balance performance of the rotor.

[0082] The above are only the preferred embodiments of the present invention, and do not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made by using the content of the specification and drawings of the present invention, or directly or indirectly applied in other related technical fields, shall be similarly included in the patent protection scope of the present invention.

Claims

1. A processing method for a motor rotor, characterized in that, Including: Hot forging the alloy steel substrate based on a preset forging temperature, and performing gradient cooling treatment on the hot-forged alloy steel substrate to obtain a rotor rough blank; Performing multi-layer gradient cutting on the rotor rough blank to obtain a cylindrical blank; Performing composite deposition treatment on the cylindrical blank based on magnetic materials to obtain a magnetic composite blank; Placing the magnetic composite blank in a vacuum environment for dynamic heat treatment to obtain a heat-treated blank; Performing dynamic balance trimming on the heat-treated blank based on a preset alloy to obtain a balanced rotor; Performing surface strengthening treatment on the balanced rotor in a nitrogen atmosphere, and coating a preset coating on the surface-strengthened balanced rotor to obtain a motor rotor with optimized surface.

2. The processing method of a motor rotor according to claim 1, wherein The alloy steel substrate is a mixture of chromium, molybdenum, carbon, nickel, vanadium, and iron elements. Among them, in the alloy steel substrate, calculated by mass percentage, the proportion of chromium is 1.5 - 3%, the proportion of molybdenum is 0.5 - 1.2%, the proportion of carbon is 0.3 - 0.6%, the proportion of nickel is 0.8 - 1.5%, the proportion of vanadium is 0.1 - 0.25%, and the balance is iron.

3. A processing method for a motor rotor according to claim 1, characterized in that, The step of hot forging the alloy steel substrate based on a preset forging temperature and performing gradient cooling treatment on the hot-forged alloy steel substrate to obtain a rotor rough blank includes: Heating the alloy steel substrate to 900 - 950°C for preheating in an inert gas atmosphere to obtain a preheated substrate; Performing multi-directional hot forging on the preheated substrate at a forging frequency of 12 - 18 times per minute and an extrusion angle of 30° - 45° to obtain a primary forged blank; Placing the primary forged blank in an environment of 700 - 800°C for 2 hours of heat preservation, and then spraying cold air on the outer surface of the primary forged blank to cool it down to 650°C to form an annealed blank; Cooling the annealed blank to 450°C at a rate of 4°C per minute through a circulating liquid cooling system, and then spraying argon on the annealed blank at a preset spraying angle for auxiliary cooling to room temperature to obtain a pre-cooled blank; Performing tempering treatment on the pre-cooled blank at 300 - 350°C for 2 hours, and reducing the tempered pre-cooled blank to 150°C based on a nitrogen circulation system to obtain a fine-tuned blank; Cooling the fine-tuned blank to 80°C at a rate of 1.5°C per minute, and then naturally cooling the fine-tuned blank to room temperature to obtain a rotor rough blank.

4. A processing method of a motor rotor according to claim 1, characterized in that, The step of performing multi-layer gradient cutting on the rotor rough blank to obtain a cylindrical blank includes: Fixing the rotor rough blank and preheating it to 200°C, and performing rough cutting of 3 - 5 mm on the outer surface of the preheated rotor rough blank at a rotational speed of 600 revolutions per minute to obtain a rough machined blank body; Performing layered peeling cutting on the rough machined blank body to obtain a layered blank, and performing precision cutting on the layered blank based on ultrasonic assistance at a frequency of 30 kHz to obtain a precision cut blank; Performing dynamic contour trimming on the precision cut blank based on a three-coordinate measuring instrument to obtain a trimmed blank, then performing tempering treatment on the trimmed blank at 150°C for 2 hours, and cutting the trimmed blank to the target size at a cutting depth of 0.3 - 0.5 mm based on a precision lathe to obtain a preformed blank; The outer surface of the preformed blank is polished and cut at a preset polishing rotation speed to obtain a cylindrical blank.

5. A processing method of a motor rotor according to claim 1, characterized in that, The step of subjecting the cylindrical blank to composite deposition treatment based on magnetic materials to obtain a magnetic composite blank includes: Based on the plasma cleaning equipment, in the working pressure, the cylindrical blank is bombarded by plasma to obtain an activated blank; The activated blank is subjected to ion carburizing treatment in a mixed gas atmosphere of methane and nitrogen to obtain a carburized blank; Spray a magnetic material on the carburized blank based on a high-frequency plasma arc to obtain a primary magnetic blank, and perform hot pressing and curing treatment on the primary magnetic blank under the working pressure of to obtain a cured magnetic blank; The cured magnetic blank is subjected to magnetic field orientation optimization treatment to obtain an oriented magnetic blank, and the surface of the oriented magnetic blank is subjected to plasma polishing treatment using a mixed gas of argon and oxygen as a polishing medium to obtain a magnetic composite blank.

6. A processing method of a motor rotor according to claim 1, characterized in that The step of placing the magnetic composite blank in a vacuum environment for dynamic heat treatment to obtain a heat-treated blank includes: Under the working air pressure, first heat the magnetic composite blank to 600 °C at a heating rate of 8 °C per minute and hold for 1.5 hours, then increase the temperature to 900 °C at a heating rate of 12 °C per minute and hold for 2 hours to obtain a strengthened blank with an enhanced magnetic layer; The strengthened blank is cooled to 700 °C at a rate of 5 °C per minute and held for 1 hour, then cooled to 550 °C at a rate of 3 °C per minute and held for 2 hours, and then cooled to 400 °C at a rate of 2 °C per minute and held for 1.5 hours to obtain a lattice-optimized blank; A constant magnetic field of 0.5 Tesla is applied to the lattice-optimized blank, and at the same time, the temperature is raised from 400 °C to 650 °C at a rate of 5 °C per minute and held for 1 hour, and then cooled to 300 °C at a rate of 4 °C per minute to obtain a magnetically optimized blank; The magnetically optimized blank is cooled to 150 °C at a rate of 2 °C per minute in an inert gas atmosphere and held for 2.5 hours to obtain a stable blank; The stable blank is cooled to room temperature at a rate of 1.5 °C per minute, and during the cooling process, it is paused for 10 minutes every 50 °C of cooling to obtain a heat-treated blank.

7. A processing method of a motor rotor according to claim 1, characterized in that The step of subjecting the heat-treated blank to dynamic balance trimming based on a preset alloy to obtain a balanced rotor includes: Based on a dynamic balance detection platform, the heat-treated blank is subjected to an initial rotation detection to obtain the initial vibration distribution characteristics of the heat-treated blank; The initial vibration distribution characteristics are deconstructed through Fourier transform and vector decomposition, the eccentric region of the heat-treated blank is calculated and marked to obtain a positioned blank; Based on a plasma spraying device, cobalt-based alloy powder is pre-deposited locally on the positioned blank to obtain a pre-trimmed blank; The pre-trimmed blank is heated to 600 °C at a rate of 5 °C per minute and held for 20 minutes, and during the heating process, a vibration with a frequency of 40 kHz is applied to the pre-trimmed blank to obtain a fine-tuned blank; Based on a dynamic balance detection platform, the fine-tuned blank is subjected to secondary balance verification, and the verification result is compared and analyzed with the initial vibration distribution characteristics to generate a residual eccentricity distribution map; According to the residual eccentricity distribution map, the fine-tuned blank is locally deposited with nickel-based alloy by electron beam welding to obtain a dynamically balanced balanced rotor.

8. A processing method of an electric motor rotor according to claim 1, characterized in that, The step of subjecting the balanced rotor to surface strengthening treatment in a nitrogen atmosphere and coating the surface-strengthened balanced rotor with a preset coating to obtain a surface-optimized motor rotor includes: The balanced rotor is subjected to ion nitriding treatment in a nitrogen atmosphere to obtain a nitrided rotor; The nitrided rotor is immersed in a composite electrolyte for micro-arc oxidation treatment to obtain an oxidation-strengthened rotor. The composite electrolyte contains silicate, phosphate, and alumina powder. The concentration of silicate is 20 g / L, the concentration of phosphate is 30 g / L, and the concentration of alumina powder is 50 g / L. The voltage of the micro-arc oxidation treatment is 450 V, the current density is 8 A / dm², and the oxidation time is 40 minutes; Based on a plasma spraying device, a ceramic coating is deposited on the oxidation-strengthened rotor using a preset coating material, and a composite coating rotor is obtained. The preset coating material includes a mixed powder of alumina and zirconia; The surface of the composite coating rotor is subjected to laser remelting treatment to obtain a remelting-strengthened rotor, and a metal film is deposited on the remelting-strengthened rotor using a high-purity titanium target as a deposition source to obtain a film layer-optimized rotor; Based on a fluorine-containing polyurethane preset coating, the film layer-optimized rotor is subjected to low-temperature curing coating to obtain a surface-optimized motor rotor.

9. A motor rotor, characterized in that, Using the processing method of the motor rotor according to any one of claims 1-8, including a shaft body and a core body. The core body is sleeved outside the shaft body. The shaft body is axially provided with an elliptical fixing groove, and the core body is fixedly connected to the shaft body through the fixing groove; The outer surface of the core body is coated with a magnetic composite layer. A plurality of pole units are embedded in the outer surface of the magnetic composite layer along the circumferential direction. The cross-section of the pole unit is trapezoidal, and an isolation strip is provided between two adjacent pole units.

10. A motor rotor according to claim 9, characterized in that, Balancing and strengthening rings are provided at opposite ends of the core body. The balancing and strengthening rings are axially provided with a plurality of balancing holes, and the balancing holes are coated with a weight alloy layer.

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