Additive manufacturing method and system applied to ultrasonic scalpel

Abstract

The invention discloses an additive manufacturing method and system applied to an ultrasonic scalpel, and relates to the field of additive manufacturing. The additive manufacturing method comprises the steps that quality control is conducted on metal powder, and meanwhile printing parameters are adjusted; post-treatment is conducted, and vibration polishing parameters are optimized; coating treatment is carried out, flow is adjusted in real time, and adhesion enhancement treatment is carried out; and testing, and performing corresponding parameter adjustment. A metal powder supply pipeline is monitored in real time, the powder stacking density and the supply rate are accurately adjusted, the laser power and the scanning speed are automatically adjusted based on real-time molten pool temperature monitoring, laser distribution of thermocouple point positions is adjusted in real time through a local temperature monitoring and regulating system, local overheating is avoided, and the service life of the metal powder is prolonged. And the vibration frequency and the cutting speed are intelligently adjusted in combination with vibration performance and cutting performance test results. The vibration frequency is optimized by monitoring the difference between the vibration intensity and the target vibration frequency in real time; the cutting speed is adjusted through the temperature distribution value, damage to the tissue caused by too high temperature is avoided, and the cutting effect and precision are improved.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing, specifically to an additive manufacturing method and system for use in ultrasonic surgical scalpels. Background Technology

[0002] Additive manufacturing (AM), also known as 3D printing, is a process that creates objects by adding materials layer by layer. Unlike traditional subtractive manufacturing techniques (such as milling and cutting), additive manufacturing builds objects by stacking materials layer by layer according to a predetermined shape and size. Common additive manufacturing techniques include selective laser melting (SLM), selective laser sintering (SLS), and electron beam melting (EBM).

[0003] Selective Laser Melting (SLM) uses a high-power laser beam to melt metal powder, creating metal parts layer by layer. It is commonly used in industries such as aerospace, automotive, and medical. SLM completely melts the metal powder using a high-power laser, thus producing very dense metal parts with high mechanical properties, approaching or reaching the strength of traditional manufacturing processes (such as casting and forging). SLM achieves high precision and detail, making it suitable for manufacturing parts with complex geometries, especially for applications in aerospace, automotive, and medical fields with high precision requirements. However, in practical applications, SLM equipment is expensive, and metal powders are also costly, especially high-performance materials such as titanium alloys and aluminum alloys. SLM-printed metal parts may require additional heat treatment and post-processing (such as support removal and surface treatment) to improve their mechanical properties and surface quality.

[0004] Existing technology, such as the invention patent with publication number CN113263187B, is an additive manufacturing method and apparatus for metallic materials, belonging to the field of additive manufacturing technology. The method includes: establishing a three-dimensional model of the workpiece to be processed; calculating the slice thickness of each layer based on a preset powder layer thickness, powder splashing degree, porosity, and the thermal expansion state of the material; performing slicing processing and path planning; controlling the descent of the forming platform and powder layer placement; and having the additive manufacturing apparatus perform melting and scanning of the powder layer according to a preset melting process and path planning data, repeating the powder layer placement and melting scanning steps to obtain the metallic material.

[0005] Existing technologies, such as the invention patent with announcement number CN106903314B, are ultrasonic selective-area laminated additive manufacturing devices and methods. The forming chamber system and the paper mold motion system are located inside the frame and fixed on its base plate. The powder spreading system is located above the forming chamber system and fixed on the intermediate support plate. The movable ultrasonic welding system and the laser scanning cutting system are fixed on the top support plate of the frame.

[0006] As can be seen from the above, existing technologies in additive manufacturing primarily focus on layered manufacturing methods. However, in practical applications, powder adhesion can be affected by various factors. During the high-temperature melting stage, different metal powder materials require different thermal stress controls. In additive manufacturing, the particle size, shape, and flowability of the metal powder significantly impact the quality of the final product. Inhomogeneous powder can lead to material inhomogeneity during printing, affecting the density and strength of the component. Furthermore, uneven local heating and cooling during additive manufacturing can also generate significant thermal stress within the component. These thermal stresses affect the material's microstructure, causing shape changes (warping, deformation) or internal cracks. Therefore, targeted control is necessary to avoid problems such as uneven density or structural instability in printed components. Summary of the Invention

[0007] To address the shortcomings of existing technologies, this invention provides an additive manufacturing method and system for ultrasonic surgical scalpels. To achieve the above objectives, this invention utilizes the following technical solution: An additive manufacturing method for ultrasonic surgical scalpels, comprising: A 3D model of the ultrasonic amplitude transformer was created, and the model was printed layer by layer by selective laser melting. During the printing process, the quality of the metal powder was controlled, and the printing parameters were adjusted.

[0008] After printing, the ultrasonic amplitude transformer is post-processed, and the vibration polishing parameters are optimized based on the additive manufacturing material.

[0009] The surface of the ultrasonic scalpel tip is coated based on additive manufacturing, and the flow rate is adjusted in real time through a control algorithm, while adhesion enhancement treatment is performed.

[0010] After manufacturing is completed, the ultrasonic scalpel is subjected to performance testing, and the parameters are adjusted accordingly based on the performance test results.

[0011] Additionally, an additive manufacturing system for ultrasonic surgical scalpels is provided, comprising: The printing module is used to create a 3D model of the ultrasonic amplitude transformer. The ultrasonic amplitude transformer model is printed layer by layer through selective laser melting. During the printing process, the quality of the metal powder is controlled and the printing parameters are adjusted.

[0012] The post-processing module is used to perform post-processing on the ultrasonic amplitude transformer after printing, optimizing the vibration polishing parameters based on the additive manufacturing material.

[0013] The coating module is used to apply a coating to the surface of the ultrasonic scalpel tip based on additive manufacturing. The flow rate is adjusted in real time through a control algorithm, while adhesion enhancement treatment is performed.

[0014] The testing module is used to perform performance tests on the ultrasonic scalpel after manufacturing is completed, and to adjust the parameters accordingly based on the performance test results.

[0015] Compared with the prior art, the embodiments of the present invention have at least the following beneficial effects: (1) This invention provides an additive manufacturing method for ultrasonic surgical scalpels, which precisely controls the powder packing density by installing a capacitive sensor to monitor the metal powder supply channel in real time. By mapping the real-time feedback of the packing density change value with the adjustment value of the metal powder supply rate, the metal powder supply rate can be effectively adjusted. This precise control can ensure the uniform laying of each layer of powder, reduce the fluctuation of material properties caused by uneven powder packing during the printing process, and thus improve the printing quality and the stability of the finished product. Especially in the printing of complex-shaped ultrasonic amplitude transformers, the uniformity and quality control of the powder are crucial, helping to avoid defects caused by powder problems, such as pores and cracks.

[0016] (2) This invention automatically adjusts the laser power and scanning speed by monitoring the molten pool temperature in real time. The molten pool temperature is obtained using an infrared temperature sensor. If the temperature is too high or too low, the system automatically adjusts the upper or lower limit of the laser power to ensure the stability of the molten pool, thereby avoiding over-melting or under-melting of the material. Simultaneously, by calculating the real-time speed-to-thickness ratio, the scanning speed of each layer during printing is automatically adjusted. This adaptive control can dynamically optimize printing parameters according to the actual printing situation, avoiding the instability of finished product quality caused by manually set fixed parameters, and ensuring the printing accuracy of each layer and the strength of the overall structure.

[0017] (3) This invention monitors the temperature of different hot spots using thermocouple sensors. When the temperature of certain hot areas exceeds the preset upper temperature limit, the laser point allocation is adjusted according to the temperature difference, thereby achieving precise local temperature control. Through this local temperature regulation, material performance degradation or burn-out caused by local overheating can be effectively avoided, further ensuring the stability and reliability of the ultrasonic amplitude transformer in subsequent applications. In addition, temperature control can also reduce printing defects caused by excessively high or low temperatures, improve the density and uniformity of the metal material, and thus enhance the mechanical properties of the final product.

[0018] (4) This invention, by combining vibration performance and cutting performance test results, can automatically adjust the vibration frequency and cutting speed. Through vibration performance testing, the vibration frequency of the ultrasonic amplitude transformer is monitored and optimized in real time to ensure it reaches the ideal resonant frequency, thereby maximizing vibration intensity and improving cutting efficiency. In the cutting performance test, the cutting speed is automatically adjusted based on the temperature distribution difference to avoid excessive damage to tissues or uneven cutting due to excessively high temperatures. This parameter adjustment based on real-time test results further optimizes the performance of the ultrasonic scalpel, improves cutting effectiveness, reduces damage to biological tissues, and ensures the high efficiency, safety, and precision of the ultrasonic scalpel in medical applications.

[0019] Of course, any product implementing this invention does not necessarily need to achieve all of the above advantages at the same time. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the method flow of the present invention.

[0021] Figure 2 This is a schematic diagram of the system modules of the present invention.

[0022] Figure 3 This is a schematic diagram of the logic flow of the present invention.

[0023] Figure 4 This is a diagram of the operation control page of a 3D printing device in another embodiment of the invention.

[0024] Figure 5 This is a continuation of the diagram showing the operation control page of a 3D printing device in another embodiment of the invention. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] In the description of this invention, it should be understood that the terms "opening", "upper", "lower", "thickness", "top", "middle", "length", "inner", "around", etc., which indicate orientation or positional relationship, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this invention.

[0027] Please see Figure 1 As shown, this embodiment of the invention provides an additive manufacturing method for an ultrasonic surgical scalpel, specifically including: like Figure 3 The diagram shown is a logic flowchart of an embodiment of the present invention, illustrating the complete process from 3D modeling to final performance testing. A series of conditional judgments and feedback mechanisms ensure optimization and adjustment at each stage. By establishing feedback mechanisms for real-time monitoring, testing feedback, and conditional judgments, each step is ensured to be adjusted according to actual conditions, improving production accuracy and product quality. The concise and clear flowchart helps to understand each stage of the entire 3D printing process and clarifies the connections and interactions between them. It demonstrates how real-time data monitoring and automated adjustments (such as powder supply rate, vibration frequency, and cutting speed) optimize the production and testing process, reducing human intervention and improving efficiency.

[0028] A 3D model of the ultrasonic amplitude transformer was created, and the model was printed layer by layer by selective laser melting. During the printing process, the quality of the metal powder was controlled, and the printing parameters were adjusted.

[0029] In this embodiment of the invention, the metal powder selected is TC4 titanium alloy, which possesses excellent corrosion resistance, superior mechanical properties, and good biocompatibility, making it highly suitable for the medical device field. Compared to stainless steel, TC4 titanium alloy has significant advantages in high strength, low density, and biocompatibility.

[0030] The capacitive sensor installed in the metal powder feeding pipeline transmits the monitored capacitance change value to the central control platform. The central control platform processes the received capacitance change value, obtains the bulk density change value of the metal powder through a preset algorithm, and feeds it back to the metal powder feeding pipeline control module. The module then performs mapping and matching on the pre-stored mapping set of bulk density change value and metal powder supply rate adjustment value in its local database to obtain the metal powder supply rate adjustment value and adjust the metal powder supply rate accordingly.

[0031] It should be noted that a capacitance sensor is installed in the metal powder supply pipeline. The capacitance sensor detects changes in capacitance caused by variations in the packing density of the metal powder within the pipeline. Since the packing density of the metal powder affects the dielectric properties of the materials in the pipeline, thus influencing the capacitance value, the capacitance sensor can obtain real-time information on changes in packing density by measuring this change. The capacitance change value measured by the capacitance sensor is transmitted to the central control platform, which is responsible for further data processing. The data received by the central control platform is converted into a usable packing density change value through signal processing and calculation, thereby reflecting the accumulation of metal powder in the pipeline. The central control platform has a preset algorithm that calculates the change in the packing density of the metal powder based on the capacitance change value. Because there is a certain relationship between capacitance change and the packing density of the metal powder, the algorithm can estimate the current packing density based on historical data and physical models.

[0032] It should also be noted that, in the embodiments of the present invention, the mapping set involved is a pre-stored data table that stores the relationship between parameters of two different dimensions. For example, the mapping set of bulk density change value - metal powder supply rate adjustment value stores and associates the relationship between bulk density change value and metal powder supply rate adjustment value. It includes the optimal metal powder supply rate adjustment amount under different bulk density conditions. The function of the mapping set is to quickly find the corresponding supply rate adjustment value from the database based on the real-time detected bulk density change value.

[0033] Printing parameters include printing laser power, scanning speed and layer thickness, and printing temperature.

[0034] The material properties of the metal powder are obtained, including thermal conductivity, melting point, and viscosity. Based on these properties, an initial laser power range is determined. During real-time printing, an infrared temperature sensor monitors the molten pool temperature. If the molten pool temperature is higher than a preset high-temperature threshold, the difference between the molten pool temperature and the high-temperature threshold is calculated to obtain the molten pool high-temperature difference. This molten pool high-temperature difference is then input into a preset mapping set of molten pool high-temperature difference - laser power upper limit adjustment value in the database for mapping and matching to obtain the laser power upper limit adjustment value.

[0035] It should be noted that, based on material property parameters obtained from the material database, the thermal conductivity of TC4 titanium alloy is approximately 6.7 W / (m*K), and its melting point is approximately 1600℃. Titanium alloys have relatively low thermal conductivity, therefore, careful thermal management is necessary during additive manufacturing to avoid deformation or quality issues caused by overheating. While the viscosity of titanium alloys in the molten state is not easily measured directly, it can be calculated through derivation. It is generally believed that titanium alloys have low viscosity in the molten state, which contributes to material flowability and molten pool formation. By monitoring the molten pool temperature in real time and adjusting the laser power when the temperature exceeds a set high-temperature threshold, overheating can be effectively avoided. Excessively high temperatures can lead to over-melting of the material, resulting in shape distortion, dimensional errors, and other problems. Adjusting the laser power helps maintain a stable molten pool temperature, ensuring the accuracy and quality of the workpiece. When the molten pool temperature falls below a preset low-temperature threshold, timely increases in laser power prevent overcooling of the molten pool, ensuring that the material is fully melted in each layer. This helps improve the material's adhesion and density, reduces defects such as porosity and cracks, and enhances the mechanical properties of the finished product.

[0036] It should also be noted that the initial laser power range is obtained based on the material property parameters of the metal powder. The specific process includes: Thermal conductivity is a parameter that measures a material's ability to transfer heat. Materials with high thermal conductivity can dissipate heat rapidly, while materials with low thermal conductivity have difficulty dissipating heat. Therefore, the thermal conductivity of metal powders directly affects the selection of laser power.

[0037] Based on the thermal conductivity of the metal powder, the initial laser power is estimated using the following formula: The relationship between heat flux density and temperature gradient is obtained based on Fourier's law: ; In practical applications, when a laser irradiates a material surface, the laser energy absorbed by the surface is converted into heat. This heat is transferred into the material's interior through the material's thermal conductivity k and the laser's effective area A. Multiplying the heat flux density by the area yields the total heat flux, i.e., the initial laser power. ; Substituting Fourier's law into the equation: ; For steady-state heat conduction, the relationship between temperature difference and heat flux density is linear. Since the calculation here uses the initial laser power, it is assumed that the temperature gradient is stable. ; Substituting the above linear relationship into the formula for total heat flow: ; Since L is a controllable parameter, it is merged into the constant term, resulting in the following simplified expression: ; Where P is the initial laser power, k is the thermal conductivity of the metal powder, and A is the laser-affected area. The melting point of the material. Let q be the ambient temperature and q be the heat flux density. Let be the temperature gradient, L be the heat conduction distance, and be a constant.

[0038] Viscosity is a measure of the resistance to liquid flow. While in additive manufacturing, viscosity is generally more related to the fluidity of molten material, it also influences the selection of laser power to some extent. Viscosity is typically related to melting temperature and the molecular structure of the material. Materials with high viscosity are more difficult to form a fluid state under laser irradiation, thus requiring adjustment of laser power to optimize melting quality. In this embodiment of the invention, the viscosity of the metal powder is input into a pre-stored viscosity-laser power range mapping set in the database for mapping and matching to obtain the laser power range value of the metal powder. This value is then combined with the initial laser power to obtain the initial laser power range. For example, if the initial laser power of a certain metal powder is 170W and the laser power range value is 30W, then the initial laser power range is 140W to 200W.

[0039] If the molten pool temperature is lower than the preset low temperature threshold, the difference between the molten pool temperature and the low temperature threshold is used to obtain the molten pool low temperature difference value. The molten pool low temperature difference value is then input into the preset mapping set of molten pool low temperature difference value - laser power lower limit adjustment value in the database for mapping and matching to obtain the laser power lower limit adjustment value.

[0040] Based on the material property parameters of the metal powder, the initial scanning speed of the printing process is obtained. It should be noted that an empirical relationship between material properties and the initial scanning speed can be established through experimental data or theoretical derivation. For example, materials with high thermal conductivity require a lower scanning speed to avoid excessive heat loss; materials with high melting points require a lower scanning speed to increase scanning time; and materials with high viscosity require an appropriately lower scanning speed to ensure molten pool flow. In this embodiment of the invention, based on the material property parameters of TC4 titanium alloy, the lowest scanning speed is selected from the mapping sets of material thermal conductivity-scanning speed, material melting point-scanning speed, and material viscosity-scanning speed, respectively, as the initial scanning speed.

[0041] Based on the preset layer thicknesses, the layer scanning speed for each layer during the printing process is obtained. It should be noted that in additive manufacturing, the thickness of each layer affects the intensity of the laser's effect on the material. Thicker layers require more laser power and a lower scanning speed to ensure sufficient melting, while thinner layers can have a higher scanning speed. Therefore, the thickness of each layer is input into a preset layer thickness-scanning speed adjustment value mapping set in the database for mapping and matching to obtain the scanning speed adjustment value. The scanning speed adjustment value for each layer is then added to the initial scanning speed to obtain the layer scanning speed for each layer.

[0042] During real-time printing, the ratio of layer scanning speed to layer thickness is calculated and denoted as the real-time speed-to-thickness ratio. When the real-time speed-to-thickness ratio is greater than the preset upper limit, the difference between the real-time speed-to-thickness ratio and the upper limit is used to obtain the speed-to-thickness ratio overspeed value. The speed-to-thickness ratio overspeed value is then entered into the preset mapping set of speed-to-thickness ratio overspeed value - scanning speed reduction value in the database for mapping and matching to obtain the layer scanning speed reduction value for that layer. If the real-time speed-to-thickness ratio is greater than the upper limit, it indicates that the scanning speed is too fast, which may lead to uneven melt pool or insufficient sintering, and the scanning speed needs to be reduced.

[0043] When the real-time speed-to-thickness ratio is less than the preset lower limit of the speed-to-thickness ratio, the difference between the real-time speed-to-thickness ratio and the lower limit of the speed-to-thickness ratio is used to obtain the low speed value of the speed-to-thickness ratio. The low speed value of the speed-to-thickness ratio is then entered into the preset mapping set of low speed value of speed-to-thickness ratio and scan speed adjustment value in the database for mapping and matching to obtain the scan speed adjustment value of the layer. If the real-time speed-to-thickness ratio is less than the lower limit of the speed-to-thickness ratio, it means that the scan speed is too slow, which will lead to low efficiency or excessive melting, and the scan speed needs to be increased.

[0044] During real-time printing, the local printing temperature of each thermocouple point is acquired in real time. If the local printing temperature of a certain thermocouple point exceeds the preset upper limit of the temperature of that thermocouple point, local temperature adjustment is performed.

[0045] It should be noted that the preset upper temperature limit is usually the safe operating temperature of the material. Exceeding this temperature may cause the material to over-melt, produce pores, generate uneven thermal expansion, or cause thermal stress and other problems.

[0046] Local temperature control includes: The local printing temperature difference is obtained by subtracting the local printing temperature from the preset upper limit value. The local printing temperature difference is then input into the pre-stored mapping set of local printing temperature difference - laser point allocation reduction value in the database for mapping and matching to obtain the laser point allocation reduction value for the thermocouple point. The number of laser points allocated to the thermocouple point is then redistributed to reduce heat accumulation in the overheated area.

[0047] After printing, the ultrasonic amplitude transformer undergoes post-processing. Based on additive manufacturing materials, vibration polishing parameters are optimized. These parameters include vibration amplitude and vibration frequency, specifically: The relationship between vibration energy, vibration amplitude, and vibration frequency is obtained as follows: ; in, Vibrational energy, The density of the metal powder f is the vibration amplitude, and f is the vibration frequency. is the specific heat capacity of the metal powder. This refers to the temperature difference, specifically the temperature change during polishing.

[0048] For the polishing process, the expression for the input heat is: ; in, Thermal power, i.e., the input heat. Thermal conductivity, For the polished surface area, The temperature difference represents the temperature change during polishing. During vibration, mechanical work is converted into heat energy, causing the metal powder to heat up. This heat energy can be transferred to the material using the formula above. The vibration amplitude and frequency indirectly affect the heat output by influencing the magnitude of mechanical energy.

[0049] For ease of calculation, under ideal conditions In practical applications, energy loss must be considered.

[0050] The relationship between temperature difference and vibration amplitude and thermal conductivity is obtained: ; in, This refers to the temperature difference, specifically the temperature change during polishing. The amplitude of vibration. Let be the thermal conductivity, and α be an empirical constant. As the vibration amplitude increases, the heat transfer efficiency will be affected, resulting in a larger temperature difference.

[0051] By obtaining the Maxwell model, the relationship between viscosity and vibration frequency is obtained. That is, as the vibration frequency increases, the viscosity of the material gradually decreases, making the surface of the material easier to polish.

[0052] Based on the above, the final expressions for vibration amplitude and vibration frequency are established as follows: ; ; in, The melting point of the material. is a constant in Maxwell's model.

[0053] It should be noted that the post-processing module is a separate system integrated with additive manufacturing, specifically designed to process and optimize the surface of the printed object. Within this module, appropriate vibration amplitude and frequency are set to achieve fine polishing of the ultrasonic amplitude transformer surface, removing uneven powder traces, minor defects, or oxide layers.

[0054] The surface of the ultrasonic scalpel tip is coated based on additive manufacturing, and the flow rate is adjusted in real time through a control algorithm, while adhesion enhancement treatment is performed.

[0055] Based on the material characteristic values, the corresponding coating material is found in the pre-stored lookup table. By matching, a coating material suitable for the current material characteristics is selected to ensure that the coating has good adhesion and durability, can effectively fuse with the substrate, and maintains stability during subsequent use.

[0056] In this embodiment of the invention, a coating is applied to the surface of the ultrasonic scalpel tip using PDA / IL coating technology, based on additive manufacturing, and the coating is prepared by liquid phase deposition.

[0057] During the coating process, the flow sensor collects coating thickness data in real time. Based on the set target coating thickness, the coating thickness error value is calculated and input into the PID control algorithm. The PID control algorithm calculates the required flow rate change based on the coating thickness error value and inputs the required flow rate change into the coating processing module to adjust the flow rate in real time.

[0058] In the PID control algorithm, the proportional component adjusts the flow rate based on the real-time error in coating thickness to minimize the error. The integral component accumulates historical coating thickness errors to adjust the flow rate and prevent the system from deviating from the target value. The derivative component predicts how the flow rate should change based on the rate of change in coating thickness, thus making adjustments in advance to avoid overcompensation or reverse regulation. The calculated flow rate change is input to the coating processing module, which adjusts the flow rate in real time during the coating process to ensure that the coating thickness reaches the target value.

[0059] The adhesion enhancement treatment specifically involves plasma removal of the oxide layer on the metal surface. During this process, the plasma treatment power is determined based on the thermal conductivity of the metal powder. It's important to note that plasma treatment technology is used to remove the oxide layer from the metal surface during the adhesion enhancement process. The oxide layer on the metal surface affects the adhesion of the coating; removing this oxide layer improves the coating's adhesion.

[0060] In plasma treatment, the appropriate plasma power needs to be determined based on the thermal conductivity of the metal powder. Thermal conductivity is a crucial material property, determining its ability to absorb and conduct heat, thus affecting the plasma treatment effect. If the thermal conductivity is low, the plasma power needs to be increased to ensure effective removal of the oxide layer. Conversely, if the thermal conductivity is high, the plasma power may need to be reduced to avoid overheating the metal material.

[0061] Based on the plasma processing power, the gas flow rate is matched. During the processing, the gas flow rate and ion density are detected by sensors and input into the PID control algorithm. If the gas flow rate is lower than the predetermined target gas flow rate, the gas flow rate is increased; if the gas flow rate is higher than the predetermined gas flow rate threshold, the gas flow rate is decreased.

[0062] If the plasma ion density exceeds the preset optimal ion density range, the gas flow rate will be adjusted. It should be noted that the plasma ion density needs to be maintained within an appropriate range. If the ion density exceeds the preset range, it may lead to uneven surface treatment or material damage; in this case, the system will trigger gas flow rate adjustment to restore the appropriate ion density range.

[0063] Since the gas flow rate adjustment process is based on the same principle as the coating flow rate adjustment process, it will not be described in detail here.

[0064] After manufacturing is completed, the ultrasonic scalpel is subjected to performance testing, and the parameters are adjusted accordingly based on the performance test results.

[0065] Performance testing includes vibration performance testing and cutting performance testing. The main purpose of vibration performance testing is to examine the relationship between the vibration frequency and cutting rate of the ultrasonic scalpel. Cutting performance testing primarily aims to examine the thermal effects of the ultrasonic scalpel during the cutting process, including temperature changes, temperature gradients, and extreme temperatures. Temperature changes directly affect the cutting effect of the ultrasonic scalpel; excessively high temperatures may lead to excessive tissue damage, while excessively low temperatures may affect cutting efficiency.

[0066] In vibration performance testing, the measured cutting rate is obtained under different test vibration amplitudes. If the measured cutting rate equals the expected cutting rate, the vibration performance test result is qualified. If the measured cutting rate is lower than the expected cutting rate, the vibration performance test result indicates a need to increase the vibration frequency. If the measured cutting rate is higher than the expected cutting rate, the vibration performance test result indicates a need to decrease the vibration frequency. The needs to increase and decrease the vibration frequency are statistically summarized as the need to adjust the vibration frequency. By adjusting the drive signal, the vibration frequency of the ultrasonic scalpel is optimized.

[0067] In the cutting performance test, temperature distribution parameters are obtained, including temperature change values, temperature gradient values, and temperature extreme values ​​in the cutting area. These parameters are then compared with preset temperature change thresholds, temperature gradient thresholds, and temperature extreme thresholds, and weighted coupling is used to obtain the temperature distribution value of the cutting area. Specifically, this includes: ; in, Let x be the temperature of the cutting region. For ambient temperature, The heat generated during cutting For the thermal conductivity of the material, The area of ​​the cut region. The cutting regions are numbered. In this embodiment of the invention, since the base number for dividing the cutting regions is 1, the value of x can be used to characterize the depth of the cutting region, where x = 1, 2, 3, ..., N, and N is the total number of cutting regions, which in this embodiment also represents the total cutting depth. In other embodiments of the invention, the relationship between depth and cutting region number is as follows: ,in, The depth of the cutting area. Number the cut areas. This serves as the base number for dividing the region.

[0068] The temperature change values ​​of the cutting area are obtained as follows: ; in, This represents the temperature change value of the cutting area.

[0069] The temperature gradient values ​​of the cut region are obtained as follows: ; in, This represents the temperature gradient value of the cut region. This represents the extreme temperature value of the cutting region.

[0070] The extreme temperature values ​​of the cut region are obtained as follows: ; The temperature distribution values ​​of the cut area are obtained as follows: ; ; in, This represents the temperature distribution value of the cut area.

[0071] If the temperature distribution value of the cutting area exceeds the preset temperature distribution threshold, the cutting performance test result is that the cutting speed needs to be reduced. If the temperature distribution value of the cutting area is less than or equal to the preset temperature distribution threshold, the cutting performance test result is qualified.

[0072] Based on the vibration performance test results, if the vibration frequency needs to be adjusted, the vibration intensity of the ultrasonic amplitude transformer is monitored in real time by an accelerometer. The resonant frequency is extracted as the target optimization frequency. The resonant frequency is the natural frequency of the ultrasonic amplitude transformer, which usually corresponds to the most efficient vibration state and helps to achieve the best cutting effect. The vibration intensity monitored in real time by the accelerometer is compared with the target vibration intensity corresponding to the target optimization frequency to obtain the vibration intensity difference value. The vibration intensity difference value is input into the PID control algorithm to control the output frequency of the ultrasonic generator in real time until the real-time vibration intensity is the same as the target vibration intensity.

[0073] Based on the cutting performance test results, if the test results indicate a need to reduce the cutting speed, the temperature distribution value of the cutting area is subtracted from a preset temperature distribution threshold to obtain the temperature distribution difference value. This difference value is then input into a pre-stored mapping set of temperature distribution difference - cutting speed reduction value in the database for mapping and matching to obtain the cutting speed reduction value for the cutting area. The temperature distribution threshold is a set safe temperature range; exceeding this value may cause overheating. The magnitude of the temperature distribution difference value reflects the deviation between the actual temperature of the cutting area and the set safe range.

[0074] like Figure 2 As shown, in this embodiment, the present invention provides an additive manufacturing system for an ultrasonic surgical scalpel, comprising: The printing module is used to create a 3D model of the ultrasonic amplitude transformer. The ultrasonic amplitude transformer model is printed layer by layer through selective laser melting. During the printing process, the quality of the metal powder is controlled and the printing parameters are adjusted.

[0075] The post-processing module is used to perform post-processing on the ultrasonic amplitude transformer after printing, optimizing the vibration polishing parameters based on the additive manufacturing material.

[0076] The coating module is used to apply a coating to the surface of the ultrasonic scalpel tip based on additive manufacturing. The flow rate is adjusted in real time through a control algorithm, while adhesion enhancement treatment is performed.

[0077] The testing module is used to perform performance tests on the ultrasonic scalpel after manufacturing is completed, and to adjust the parameters accordingly based on the performance test results.

[0078] like Figure 4 and Figure 5The diagram shown is an operation control page of a 3D printing device according to another embodiment of the invention, including device control and device self-test. Device control includes control buttons for power control, nozzle heating, cooling fan, adhesion enhancement treatment, start printing, pause printing, stop printing, and system settings. Device self-test includes displays for nozzle heating, heated bed heating, nozzle cooling fan, motherboard cooling fan, leveling optimization, and automatic leveling. The device control section is used for real-time operation and adjustment of various settings during the printing process, while the device self-test function ensures that all parts of the device are in normal working condition, preventing equipment failure or abnormalities and ensuring the smooth completion of printing tasks. The two complement each other, jointly ensuring the efficient, safe, and stable operation of the 3D printer.

[0079] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0080] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementation methods. Clearly, many modifications and variations can be made based on the content of this specification. The selection and detailed description of these embodiments in this specification are intended to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. Any modifications or variations that do not deviate from the structure of the invention or exceed the scope defined by the invention should fall within the protection scope of the invention.

Claims

1. An additive manufacturing method for use in ultrasonic surgical scalpels, characterized in that, include: A three-dimensional model of the ultrasonic amplitude transformer was created, and the model was printed layer by layer by selective laser melting. During the printing process, the quality of the metal powder was controlled and the printing parameters were adjusted. After printing, the ultrasonic amplitude transformer is post-processed, and the vibration polishing parameters are optimized based on the additive manufacturing material. The surface of the ultrasonic scalpel tip is coated on the basis of additive manufacturing, and the flow rate is adjusted in real time through a control algorithm, while adhesion enhancement treatment is performed simultaneously. After manufacturing is completed, the ultrasonic scalpel is subjected to performance testing, and the parameters are adjusted accordingly based on the performance test results.

2. The additive manufacturing method for an ultrasonic surgical scalpel according to claim 1, characterized in that: The specific process for quality control of the metal powder is as follows: The capacitive sensor installed in the metal powder feeding pipeline transmits the monitored capacitance change value to the central control platform. The central control platform processes the received capacitance change value, obtains the bulk density change value of the metal powder through a preset algorithm, and feeds it back to the metal powder feeding pipeline control module. The module then performs mapping and matching on the pre-stored mapping set of bulk density change value and metal powder supply rate adjustment value in its local database to obtain the metal powder supply rate adjustment value and adjust the metal powder supply rate accordingly.

3. The additive manufacturing method for an ultrasonic surgical scalpel according to claim 1, characterized in that: The adjustment of printing parameters specifically includes: The printing parameters include printing laser power, scanning speed and layer thickness, and printing temperature; The material properties parameters of the metal powder are obtained, including thermal conductivity, melting point and viscosity. Based on the material properties parameters of the metal powder, the initial laser power range is obtained. During real-time printing, the molten pool temperature is monitored in real time using an infrared temperature sensor. If the molten pool temperature is higher than the preset high temperature threshold, the difference between the molten pool temperature and the high temperature threshold is obtained to get the molten pool high temperature difference value. The molten pool high temperature difference value is then entered into the preset mapping set of molten pool high temperature difference value - laser power upper limit adjustment value in the database for mapping and matching to obtain the laser power upper limit adjustment value. If the molten pool temperature is lower than the preset low temperature threshold, the difference between the molten pool temperature and the low temperature threshold is used to obtain the molten pool low temperature difference value. The molten pool low temperature difference value is then input into the preset mapping set of molten pool low temperature difference value - laser power lower limit adjustment value in the database for mapping and matching to obtain the laser power lower limit adjustment value. Based on the material property parameters of the metal powder, the initial scanning speed of the printing process is obtained. Based on the preset thickness of each layer, the layer scanning speed of each layer during the printing process is obtained. During real-time printing, the ratio of the layer scanning speed to the layer thickness is calculated and recorded as the real-time speed-to-thickness ratio. When the real-time speed-to-thickness ratio is greater than the preset upper limit of the speed-to-thickness ratio, the difference between the real-time speed-to-thickness ratio and the upper limit of the speed-to-thickness ratio is used to obtain the speed-to-thickness ratio overspeed value. The speed-to-thickness ratio overspeed value is input into the preset mapping set of speed-to-thickness ratio overspeed value - scanning speed reduction value in the database for mapping and matching to obtain the layer scanning speed reduction value of that layer. When the real-time speed-to-thickness ratio is less than the preset lower limit of the speed-to-thickness ratio, the difference between the real-time speed-to-thickness ratio and the lower limit of the speed-to-thickness ratio is used to obtain the low speed value of the speed-to-thickness ratio. The low speed value of the speed-to-thickness ratio is then entered into the preset mapping set of low speed value of speed-to-thickness ratio - scanning speed adjustment value in the database for mapping and matching to obtain the level scanning speed adjustment value for that level. The process of obtaining the layer scanning speed of each layer during the printing process specifically includes: inputting the thickness of each layer into a preset mapping set of layer thickness-scanning speed adjustment values ​​in the database, performing mapping matching to obtain the scanning speed adjustment value, and coupling the scanning speed adjustment value of each layer with the initial scanning speed to obtain the layer scanning speed of each layer. During real-time printing, the local printing temperature of each thermocouple point is acquired in real time. If the local printing temperature of a thermocouple point exceeds the preset upper limit of the temperature of that thermocouple point, local temperature adjustment is performed. Local temperature control includes: The local printing temperature difference is obtained by subtracting the local printing temperature from the preset upper limit value. The local printing temperature difference is then input into the pre-stored mapping set of local printing temperature difference - laser point allocation reduction value in the database for mapping and matching to obtain the laser point allocation reduction value for the thermocouple point. Finally, the number of laser points allocated to the thermocouple point is reallocated.

4. The additive manufacturing method for an ultrasonic surgical scalpel according to claim 1, characterized in that: The post-processing of the ultrasonic amplitude transformer, based on the optimization of vibration polishing parameters using additive manufacturing materials, specifically includes: Based on additive manufacturing materials, the vibration polishing parameters, including vibration amplitude and vibration frequency, are optimized, and the vibration polishing parameters of the ultrasonic amplitude transformer are combined and applied to the post-processing module.

5. The additive manufacturing method for an ultrasonic surgical scalpel according to claim 1, characterized in that: The real-time flow adjustment via control algorithm specifically includes: Based on the material characteristic values, the corresponding coating material is found in a pre-stored lookup table; During the coating process, the flow sensor collects coating thickness data in real time. Based on the set target coating thickness, the coating thickness error value is calculated and input into the PID control algorithm. The PID control algorithm calculates the required flow rate change based on the coating thickness error value and inputs the required flow rate change into the coating processing module to adjust the flow rate in real time.

6. The additive manufacturing method for an ultrasonic surgical scalpel according to claim 1, characterized in that: The adhesion enhancement treatment specifically includes: The adhesion enhancement treatment specifically involves plasma removal of the oxide layer on the metal surface. During the adhesion enhancement treatment, the plasma processing power is determined based on the thermal conductivity of the metal powder. Based on the plasma processing power, the gas flow rate is matched. During the processing, the gas flow rate and ion density are detected by sensors and input into the PID control algorithm. If the gas flow rate is lower than the predetermined target gas flow rate, the gas flow rate is increased; if the gas flow rate is higher than the predetermined gas flow rate threshold, the gas flow rate is decreased. If the plasma ion density exceeds the preset optimal ion density range, the gas flow rate adjustment will be triggered.

7. The additive manufacturing method for an ultrasonic surgical scalpel according to claim 1, characterized in that: The specific processing conditions for performing performance testing on the ultrasonic surgical scalpel are as follows: The performance tests include vibration performance tests and cutting performance tests; In the vibration performance test, the measured cutting rate under different test vibration amplitudes is obtained. If the measured cutting rate is equal to the expected cutting rate, the vibration performance test result is qualified. If the measured cutting rate is lower than the expected cutting rate, the vibration performance test result indicates that the vibration frequency needs to be increased. If the measured cutting rate is higher than the expected cutting rate, the vibration performance test result indicates that the vibration frequency needs to be decreased. The requirements for increasing and decreasing the vibration frequency are statistically summarized as the requirement for adjusting the vibration frequency. By adjusting the drive signal, the vibration frequency of the ultrasonic scalpel is optimized. In the cutting performance test, temperature distribution parameters are obtained, including temperature change value, temperature gradient value, and temperature extreme value of the cutting area. These parameters are compared with preset temperature change threshold, temperature gradient threshold, and temperature extreme threshold, and then weighted and coupled to obtain the temperature distribution value of the cutting area. If the temperature distribution value of the cutting area exceeds the preset temperature distribution threshold, the cutting performance test result requires a reduction in cutting speed. If the temperature distribution value of the cutting area is less than or equal to the preset temperature distribution threshold, the cutting performance test result is qualified.

8. The additive manufacturing method for an ultrasonic surgical scalpel according to claim 1, characterized in that: The specific processing conditions for adjusting the parameters based on the performance test results are as follows: Based on the vibration performance test results, if the vibration performance test results indicate that the vibration frequency needs to be adjusted, the vibration intensity of the ultrasonic amplitude transformer is monitored in real time by an accelerometer, and the resonant frequency is extracted as the target optimized frequency. The vibration intensity monitored in real time by the accelerometer is compared with the target vibration intensity corresponding to the target optimized frequency to obtain the vibration intensity difference value. The vibration intensity difference value is input into the PID control algorithm to control the output frequency of the ultrasonic generator in real time until the real-time vibration intensity is the same as the target vibration intensity.

9. The additive manufacturing method for an ultrasonic surgical scalpel according to claim 1, characterized in that: The specific processing conditions for adjusting the parameters based on the performance test results are as follows: Based on the cutting performance test results, if the cutting performance test results indicate a need to reduce the cutting speed, the temperature distribution value of the cutting area is subtracted from the preset temperature distribution threshold to obtain the temperature distribution difference value. This difference value is then input into the pre-stored mapping set of temperature distribution difference - cutting speed reduction value in the database for mapping and matching to obtain the cutting speed reduction value of the cutting area.

10. A system employing the additive manufacturing method for an ultrasonic surgical scalpel as described in any one of claims 1-9, characterized in that: The printing module is used to create a 3D model of the ultrasonic amplitude transformer. The ultrasonic amplitude transformer model is printed layer by layer by selective laser melting. During the printing process, the quality of the metal powder is controlled and the printing parameters are adjusted. The post-processing module is used to perform post-processing on the ultrasonic amplitude transformer after printing, optimizing the vibration polishing parameters based on the additive manufacturing material. The coating module is used to apply a coating to the surface of the ultrasonic scalpel tip based on additive manufacturing. The flow rate is adjusted in real time through a control algorithm, and adhesion enhancement treatment is performed simultaneously. The testing module is used to perform performance tests on the ultrasonic scalpel after manufacturing is completed, and to adjust the parameters accordingly based on the performance test results.

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