3D printing optimization process based on granular material melting

Abstract

According to the 3D printing optimization process based on particle material melting, through an intelligent feeding device and a closed-loop control system, accurate control over the feeding amount can be achieved, uniform feeding of materials is ensured, and therefore the interlayer bonding strength of a printed piece is improved; the defects caused by uneven feeding are reduced, temperature distribution can be automatically adjusted according to the material characteristics and the thickness of a printing layer by adopting a multi-stage heating device with partition temperature control and a dynamic temperature adjusting module, uniform melting of particles is guaranteed, the problem of local overheating or insufficient cooling is reduced, and finally the mechanical performance of a printed piece is improved. According to the 3D printing optimization process based on granular material melting, a computer numerical control system and a path optimization algorithm are utilized, the nozzle moving speed and the material extrusion speed which are adjusted in real time are combined, the geometric accuracy and the surface quality of a printed piece are ensured, meanwhile, the printing time is shortened, and the production efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and in particular to a 3D printing optimization process based on melting of granular materials. Background Art

[0002] With the widespread application of 3D printing technology, especially in industrial manufacturing, aerospace and medical fields, the requirements for printing accuracy and finished product quality are increasing. Traditional 3D printing processes based on filaments or powders have certain limitations in accuracy, speed, and material utilization. To solve these problems, 3D printing technology based on granular melting has emerged, which can not only improve printing accuracy, but also utilize a wider range of material types. However, the existing 3D printing process based on granular materials still has many technical challenges in terms of material supply, melting control, molding speed and post-processing, such as poor inter-layer bonding caused by unstable feeding, inconsistent material properties caused by uneven melting, and substandard surface quality of finished products.

[0003] To solve the above problems, the present invention proposes a 3D printing optimization process based on the melting of granular materials. By comprehensively optimizing the steps of granular material pretreatment, precise feeding control, multi-stage melting heating, precision molding and surface treatment, the molding accuracy of 3D printing and the quality of the final product can be greatly improved, which is suitable for industrial applications with high precision requirements. Summary of the invention

[0004] The purpose of the present invention is to provide a 3D printing optimization process based on melting of granular materials to solve the problems existing in the prior art mentioned in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution, a 3D printing optimization process based on melting of granular materials, comprising the following steps:

[0006] S1. Pretreatment of pellets

[0007] Preheat the granular material to be printed to ensure that the granular material has a consistent temperature and control the humidity according to the material characteristics;

[0008] S2. Quantitative supply of pellets

[0009] The granular material is accurately fed into the printer according to the set supply amount through the intelligent feeding device;

[0010] S3. Melting of pellets

[0011] A multi-stage heating device is used to heat and melt the granular material layer by layer;

[0012] S4. Layer by layer molding

[0013] By precisely controlling the movement path and speed of the print head, the molten material is deposited layer by layer and quickly solidified in combination with the cooling system.

[0014] S5. Post-molding processing

[0015] Perform necessary surface treatment on the formed 3D printed parts.

[0016] Preferably, step S1 specifically includes the following steps:

[0017] S11. Use a hot air drying device with timing and temperature control functions to preheat the pellets at a constant temperature of 70°C for 3 hours;

[0018] S12. Utilize a humidity control system and use a precise humidity sensor to monitor and maintain the humidity of the pellet storage environment between 6% and 7% in real time. When the humidity exceeds the set range, the dehumidification or humidification equipment is automatically started to adjust the humidity;

[0019] S13. Automatically screen the granular material, set the screening particle size to 0.5 mm to 2 mm, and remove particles that do not meet the requirements.

[0020] Preferably, step S2 specifically includes the following steps:

[0021] S21. A high-precision flow sensor is provided in the feeding device, and the feeding rate is automatically adjusted through a closed-loop control system in real time feedback;

[0022] S22. The feed amount is precisely adjusted through a closed-loop control system to maintain a fluctuation range of the feed amount within ±0.5 g;

[0023] S23. A constant temperature heating module is integrated in the feeding device to keep the temperature of the pellets constant at 70℃±2℃ during the conveying process.

[0024] Preferably, step S3 specifically includes the following steps:

[0025] S31. The multi-stage heating device is divided into at least three independently controlled heating zones, and the temperature setting of each zone is 180°C, 210°C, and 240°C, respectively, and the temperature is automatically adjusted according to the melting point of the granular material and the target printing layer thickness;

[0026] S32. Use temperature gradient control technology during the melting process to gradually increase the temperature;

[0027] S33. Equipped with a dynamic temperature adjustment module to detect and adjust the temperature distribution of the heating area in real time.

[0028] Preferably, step S4 specifically includes the following steps:

[0029] S41. Use a precision computer numerical control system to monitor the movement path of the print head in real time and reduce printing time through a path optimization algorithm;

[0030] S42. During the molding process, the nozzle movement speed and material extrusion rate are dynamically adjusted according to the real-time calculated printing layer thickness and geometry to ensure that the interlayer bonding strength reaches more than 30 MPa and the surface finish reaches Ra1.6 microns;

[0031] S43. Use efficient air cooling or water cooling system to quickly solidify each printed layer within 5 seconds, and the cooling temperature is controlled between 20℃ and 30℃. Start printing the next layer immediately after solidification.

[0032] Preferably, step S5 specifically includes the following steps:

[0033] S51. Perform all-round automated surface inspection on the 3D printed parts after molding, including surface smoothness, interlayer bonding strength and material uniformity, with an inspection accuracy of 0.01 mm, and record and archive the inspection results;

[0034] S52. Based on the surface inspection results, local repair of surface defects is performed through automated processing equipment;

[0035] S53. After surface treatment, the printed parts are tested for physical and mechanical properties, including tensile strength (>50 MPa), hardness (>80 Shore A hardness), and wear resistance.

[0036] Preferably, the humidity control system of step S12 further comprises:

[0037] S121. Set up an environmental humidity monitoring module to monitor the humidity changes in the printing room in real time, with a sampling interval of 10 seconds, and automatically adjust the storage environment humidity of the granular material through the central control system, and control the humidity fluctuation within ±1%;

[0038] S122. When the humidity exceeds the set range, the dehumidification or humidification equipment is automatically started to quickly return the ambient humidity to between 6% and 7%.

[0039] Preferably, the closed-loop control system in step S22 includes:

[0040] S221. Equipped with a feeding rate feedback module, which detects and feeds back the feeding rate to the control system. The system automatically adjusts the feeding amount according to real-time data, and the feeding rate error does not exceed ±0.2 grams;

[0041] S222. The feed rate feedback module is synchronized with the movement path of the print head.

[0042] Preferably, the dynamic temperature adjustment module of step S33 further includes:

[0043] S331. Equipped with infrared temperature sensor to monitor the temperature distribution of pellets in the melting process in real time and adjust the power of each heating area through data feedback control system.

[0044] S332. The temperature sensor data is fed back to the control system in real time to adjust the power output of each heating area.

[0045] Preferably, the efficient cooling system in step S43 further comprises:

[0046] S431. Use dual-channel cooling technology, one channel is used to quickly cool the printed layer surface, and the other channel is used to cool the unprinted area;

[0047] S432. The cooling system is linked with the printing path planning system to dynamically adjust the cooling wind speed and cooling path by calculating the heat distribution and material properties of each printing area.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] 1. The 3D printing optimization process based on melting of granular materials can achieve precise control of the feeding amount through an intelligent feeding device and a closed-loop control system, ensuring uniform supply of materials, thereby improving the interlayer bonding strength of printed parts and reducing defects caused by uneven feeding;

[0050] 2. The 3D printing optimization process based on melting of pellets adopts a multi-stage heating device with zoned temperature control and a dynamic temperature adjustment module, which can automatically adjust the temperature distribution according to the material characteristics and the thickness of the printing layer, ensure the uniform melting of the pellets, reduce the problem of local overheating or insufficient cooling, and ultimately improve the mechanical properties of the printed parts;

[0051] 3. The 3D printing optimization process based on melting of pellets uses a computer numerical control system and a path optimization algorithm, combined with real-time adjustment of the nozzle movement speed and material extrusion rate to ensure the geometric accuracy and surface quality of the printed parts, while shortening the printing time and improving production efficiency;

[0052] 4. The efficient cooling system of the 3D printing optimization process based on the melting of pellets uses dual-channel cooling technology to achieve rapid solidification of the printed layer and prevent deformation caused by heat accumulation. Subsequent surface treatment and testing steps ensure the surface finish and consistency of the finished product, meeting industrial standards;

[0053] 5. The optimized 3D printing process based on melting of granular materials can accurately detect the surface defects of the printed parts through the automated surface inspection and repair system in the post-molding processing stage, and perform laser repair or polishing based on the inspection results, further improving the quality and service life of the printed parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 The present invention is a flow chart of a 3D printing optimization process based on melting of granular materials. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0056] In the description of the invention, it should be noted that the terms "upper", "lower", "inner", "outer", "front end", "rear end", "two ends", "one end", "the other end" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore cannot be understood as limiting the invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0057] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0058] See also Figure 1 The present invention provides a technical solution: a 3D printing optimization process based on melting of granular materials, comprising the following steps:

[0059] S1. Pretreatment of pellets

[0060] Preheat the granular material to be printed to ensure that the granular material has a consistent temperature and control the humidity according to the material characteristics;

[0061] S2. Quantitative supply of pellets

[0062] The granular material is accurately fed into the printer according to the set supply amount through the intelligent feeding device;

[0063] S3. Melting of pellets

[0064] A multi-stage heating device is used to heat and melt the granular material layer by layer;

[0065] S4. Layer by layer molding

[0066] By precisely controlling the movement path and speed of the print head, the molten material is deposited layer by layer and quickly solidified in combination with the cooling system.

[0067] S5. Post-molding processing

[0068] Perform necessary surface treatment on the formed 3D printed parts.

[0069] Specifically, through comprehensive optimization of steps such as pretreatment, quantitative supply, melting, layer-by-layer molding and post-molding processing, the present invention can effectively improve the accuracy and material utilization rate of 3D printing, reduce defects and material waste in the printing process, preheating and humidity control ensure the uniformity of the granular material, quantitative supply accurately controls the material usage, layer-by-layer molding combined with a cooling system improves the strength and surface quality of the printed part, and post-molding processing further optimizes the final performance of the printed part.

[0070] The S1 step specifically includes the following steps:

[0071] S11. Use a hot air drying device with timing and temperature control functions to preheat the pellets at a constant temperature of 70°C for 3 hours;

[0072] S12. Utilize a humidity control system and use a precise humidity sensor to monitor and maintain the humidity of the pellet storage environment between 6% and 7% in real time. When the humidity exceeds the set range, the dehumidification or humidification equipment is automatically started to adjust the humidity;

[0073] S13. Automatically screen the granular material, set the screening particle size to 0.5 mm to 2 mm, and remove particles that do not meet the requirements.

[0074] Specifically, through specific pretreatment steps, especially the precise control of the temperature and humidity of the granular materials, the physical properties of the granular materials are ensured to remain stable during the printing process, thereby avoiding the decline in printing quality due to changes in material properties. Automated particle size screening ensures the uniformity of the granular materials and improves the structural consistency and mechanical properties of the printed parts.

[0075] Wherein, step S2 specifically includes the following steps:

[0076] S21. A high-precision flow sensor is provided in the feeding device, and the feeding rate is automatically adjusted through a closed-loop control system in real time feedback;

[0077] S22. The feed amount is precisely adjusted through a closed-loop control system to maintain a fluctuation range of the feed amount within ±0.5 g;

[0078] S23. A constant temperature heating module is integrated in the feeding device to keep the temperature of the pellets constant at 70℃±2℃ during the conveying process.

[0079] Specifically, the real-time monitoring and adjustment of the material supply through high-precision flow sensors and closed-loop control systems can highly match the material supply with the printing speed, reducing printing defects caused by uneven material supply. The constant temperature heating module ensures that the granular material maintains an appropriate temperature during the conveying process, avoiding material blockage or melting problems caused by temperature fluctuations, thereby ensuring the continuity and stability of the printing process.

[0080] The S3 step specifically includes the following steps:

[0081] S31. The multi-stage heating device is divided into at least three independently controlled heating zones, and the temperature setting of each zone is 180°C, 210°C, and 240°C, respectively, and the temperature is automatically adjusted according to the melting point of the granular material and the target printing layer thickness;

[0082] S32. Use temperature gradient control technology during the melting process to gradually increase the temperature;

[0083] S33. Equipped with a dynamic temperature adjustment module to detect and adjust the temperature distribution of the heating area in real time.

[0084] Specifically, through the multi-stage heating device with zoned temperature control and the dynamic temperature adjustment module, the melting of the granular material during the printing process is more uniform. The temperature gradient control technology avoids local overheating or insufficient cooling, ensuring the bonding strength of the printed layer. The accuracy of temperature control shows obvious advantages, especially in the printing of complex geometric shapes, which can effectively reduce thermal deformation and improve the dimensional accuracy of the printed parts.

[0085] Wherein, step S4 specifically includes the following steps:

[0086] S41. Use a precision computer numerical control system to monitor the movement path of the print head in real time and reduce printing time through a path optimization algorithm;

[0087] S42. During the molding process, the nozzle movement speed and material extrusion rate are dynamically adjusted according to the real-time calculated printing layer thickness and geometry to ensure that the interlayer bonding strength reaches more than 30 MPa and the surface finish reaches Ra1.6 microns;

[0088] S43. Use efficient air cooling or water cooling system to quickly solidify each printed layer within 5 seconds, and the cooling temperature is controlled between 20℃ and 30℃. Start printing the next layer immediately after solidification.

[0089] Specifically, through the application of the path optimization algorithm, the present invention significantly improves printing efficiency and reduces material waste. The dynamic adjustment of the nozzle movement speed and the material extrusion rate ensures the strength of the interlayer bonding and the surface quality. At the same time, the efficient cooling system effectively prevents deformation or cracking caused by heat accumulation, ensuring that the printed parts have good structural integrity and surface finish.

[0090] Specifically, the path optimization algorithm can adopt the A* algorithm or the Dijkstra algorithm. Among them, the A* algorithm estimates the total path cost from the starting point to the end point and combines it with a heuristic estimation function to select the optimal path. The heuristic estimation function is generally based on the straight-line distance from the current node to the target node. The A* algorithm can comprehensively consider the length of the path and the search efficiency in the path search, and is often used for complex path planning problems. The Dijkstra algorithm is a classic algorithm for finding the shortest path from a single source. It gradually expands the path of each node and selects the current shortest path. The Dijkstra algorithm does not rely on heuristic functions during the search process, so it is suitable for scenarios where the absolute shortest path needs to be found.

[0091] Specifically, in the 3D printing path planning of the present invention, the A* algorithm or the Dijkstra algorithm is used to optimize the moving path of the print nozzle. Assuming that when printing complex geometric shapes, the nozzle needs to move to multiple specified points (point A, point B, point C), each point represents a different printing area. In order to improve printing efficiency and reduce material waste, the system will calculate the best path for the nozzle to move from the starting point to the end point based on the current geometric shape. Using the A* algorithm, the system will calculate each possible path and use the heuristic function to estimate the minimum cost path for the nozzle to reach the end point. Assuming that the current path A→C→B is shorter than A→B→C, the system will select A→C→B as the nozzle movement path. Using the Dijkstra algorithm, the system will gradually expand the path of each node and calculate the minimum cost path to the next node. Assuming that the current path A→B→C has the lowest total cost, the system will select this path.

[0092] Wherein, step S5 specifically includes the following steps:

[0093] S51. Perform all-round automated surface inspection on the 3D printed parts after molding, including surface smoothness, interlayer bonding strength and material uniformity, with an inspection accuracy of 0.01 mm, and record and archive the inspection results;

[0094] S52. Based on the surface inspection results, local repair of surface defects is performed through automated processing equipment;

[0095] S53. After surface treatment, the printed parts are tested for physical and mechanical properties, including tensile strength (>50 MPa), hardness (>80 Shore A hardness), and wear resistance.

[0096] Specifically, the quality of 3D printed parts is further improved through automated surface inspection and repair processes. Strict inspection and repair of indicators such as surface smoothness and interlayer bonding strength ensure that the quality of the finished products meets industrial standards. In addition, physical and mechanical property tests ensure the durability and reliability of the printed parts, meeting the high requirements of practical applications.

[0097] Wherein, the humidity control system of step S12 further comprises:

[0098] S121. Set up an environmental humidity monitoring module to monitor the humidity changes in the printing room in real time, with a sampling interval of 10 seconds, and automatically adjust the storage environment humidity of the granular material through the central control system, and control the humidity fluctuation within ±1%;

[0099] S122. When the humidity exceeds the set range, the dehumidification or humidification equipment is automatically started to quickly return the ambient humidity to between 6% and 7%.

[0100] Specifically, by precisely controlling humidity, the present invention can effectively prevent material properties from changing due to fluctuations in ambient humidity. The activation of automatic dehumidification or humidification equipment stabilizes the physical properties of the granular material, ensuring the smooth progress of the printing process and the quality consistency of the printouts.

[0101] Wherein, the closed-loop control system in step S22 includes:

[0102] S221. Equipped with a feeding rate feedback module, which detects and feeds back the feeding rate to the control system. The system automatically adjusts the feeding amount according to real-time data, and the feeding rate error does not exceed ±0.2 grams;

[0103] S222. The feed rate feedback module is synchronized with the movement path of the print head.

[0104] Specifically, the application of the feed rate feedback module makes the material supply more accurate, and the matching degree between the feed rate and the printing speed is significantly improved, which reduces the problem of insufficient or excessive feed during the printing process, thereby improving the overall quality of the printed part. This module is particularly effective during high-speed printing, and can ensure that the internal structure of the printed part is uniform and defect-free.

[0105] The dynamic temperature adjustment module of step S33 further includes:

[0106] S331. Equipped with infrared temperature sensor to monitor the temperature distribution of pellets in the melting process in real time and adjust the power of each heating area through data feedback control system.

[0107] S332. The temperature sensor data is fed back to the control system in real time to adjust the power output of each heating area.

[0108] Specifically, the application of infrared temperature sensors ensures the accuracy of temperature control during the printing process, especially when printing complex geometric shapes. It can adjust the power of each heating area in real time to ensure uniform melting of the material and reduce thermal deformation and other temperature-related defects.

[0109] Wherein, the efficient cooling system in step S43 further comprises:

[0110] S431. Use dual-channel cooling technology, one channel is used to quickly cool the printed layer surface, and the other channel is used to cool the unprinted area;

[0111] S432. The cooling system is linked with the printing path planning system to dynamically adjust the cooling wind speed and cooling path by calculating the heat distribution and material properties of each printing area.

[0112] Specifically, the application of the dual-channel cooling system makes the cooling process more efficient. It can not only quickly cool the surface of the printed layer, but also maintain the temperature stability of the unprinted area, avoiding material shrinkage or deformation caused by uneven temperature. The dynamic adjustment of the cooling intensity and path also makes the entire printing process more controllable, further improving the dimensional accuracy and surface quality of the printed parts.

[0113] Example 1

[0114] S1: Pretreatment of pellets.

[0115] S11: Use a hot air drying device with timing and temperature control functions, model Witte10X-60 dryer, to preheat the ABS material pellets for 3 hours at a constant temperature of 70°C to ensure uniform temperature inside and outside the pellets.

[0116] S12: Utilize the humidity control system and use precise humidity sensors to monitor and maintain the humidity of the pellet storage environment between 6% and 7% in real time. When the humidity exceeds the set range, the dehumidification or humidification equipment is automatically started to adjust the humidity.

[0117] S121: Setting an environmental humidity monitoring module to monitor the humidity changes in the printing room in real time, with a sampling interval of 10 seconds, and automatically adjusting the storage environment humidity of the granular material through the central control system, and controlling the humidity fluctuation within ±1%.

[0118] S122: When the humidity exceeds the set range, the dehumidification or humidification equipment is automatically started to quickly return the ambient humidity to between 6% and 7% to maintain the best processing conditions for the granular material and prevent the material properties from being affected by humidity changes.

[0119] S13: The granular material is automatically screened for particle size, and the screening particle size is set to 0.5 mm to 2 mm. Particles that do not meet the requirements are removed to ensure the size consistency of the material during the printing process, thereby improving the printing accuracy.

[0120] S2: quantitative supply of pellets.

[0121] S21: A high-precision flow sensor is set in the feeding device of model BrabenderDDSR20. The feeding amount of the feeding device is set to 8 grams per second. The feeding rate of the granular material can be monitored at intervals of 0.1 seconds, and the feeding rate can be automatically adjusted through real-time feedback and a closed-loop control system to ensure that the feeding matches the printing progress.

[0122] S22: The feed amount is precisely adjusted through a closed-loop control system to keep the fluctuation range of the feed amount within ±0.5 grams to ensure the consistency of material supply for each layer and avoid insufficient interlayer bonding strength caused by uneven feed.

[0123] S221: Equipped with a feeding rate feedback module, it can detect and feed back the feeding rate to the control system at a frequency of 10 times per second. The system automatically adjusts the feeding amount according to real-time data, and the feeding rate error does not exceed ±0.2 grams.

[0124] S222: The feed rate feedback module is synchronized with the moving path of the print head to ensure that the feed amount is highly matched with the actual printing demand, avoiding printing defects caused by excessive or insufficient feed, and the feed deviation does not exceed ±0.1 grams.

[0125] S23: A constant temperature heating module is integrated in the feeding device to keep the temperature of the pellets constant at 70℃±2℃ during the transportation process, so as to avoid melting or clogging of the pellets in the feeding pipeline due to temperature fluctuations.

[0126] S3: Melting of granular material.

[0127] S31: Set up a multi-stage heating device of model LeisterLHS61L. The multi-stage heating device is divided into at least three independently controlled heating zones. The temperature settings of each zone are 180°C, 210°C, and 240°C respectively. The temperature is automatically adjusted according to the melting point of the granular material and the target printing layer thickness to avoid overheating or incomplete melting.

[0128] S32: Temperature gradient control technology is used during the melting process. By gradually increasing the temperature (the temperature increase of each layer does not exceed 10°C), the granular material is ensured to melt evenly from the outer layer to the inner layer, reducing local overheating or insufficient cooling, and the melting time is controlled between 5 and 10 seconds.

[0129] S33: Equipped with a dynamic temperature regulation module, it detects and adjusts the temperature distribution of the heating area in real time. Especially when printing complex geometric shapes, the infrared temperature sensor accurately monitors the temperature distribution to ensure that each layer of material is melted evenly.

[0130] S331: Equipped with an infrared temperature sensor with a measuring range of 50°C to 300°C and an accuracy of ±2°C. It is used to monitor the temperature distribution of pellets during the melting process in real time and adjust the power of each heating area through a data feedback control system.

[0131] S332: The temperature sensor data is fed back to the control system in real time. By adjusting the power output of each heating area, the temperature distribution is precisely controlled to ensure melting uniformity. Even in the printing process of complex geometric shapes, the temperature error is controlled within ±5°C.

[0132] S4: Layer by layer molding.

[0133] S41: Use a precision computer numerical control system to monitor the movement path of the print head in real time, and use a path optimization algorithm (such as A* algorithm or Dijkstra algorithm) to reduce printing time and material waste. The optimized path deviation does not exceed 0.1 mm.

[0134] S42: During the molding process, the nozzle movement speed (10 to 50 mm / s) and the material extrusion rate are dynamically adjusted according to the real-time calculated printing layer thickness and geometry to ensure that the interlayer bonding strength reaches more than 30 MPa and the surface finish reaches Ra1.6 microns.

[0135] S43: Use efficient air cooling or water cooling system to quickly solidify each printed layer within 5 seconds. The cooling temperature is controlled between 20℃ and 30℃. Start the next layer of printing immediately after solidification to avoid material deformation or cracking caused by heat accumulation.

[0136] S431: Dual-channel cooling technology is used, one channel is used to quickly cool the surface of the printed layer, and the other channel is used to cool the unprinted area. The cooling wind speed is set to 2 to 4 meters per second, and the coolant flow rate is set to 1 to 2 liters per second to ensure that the surface temperature of the printed part is below 30°C.

[0137] S432: The cooling system is linked with the printing path planning system to dynamically adjust the cooling wind speed and cooling path by calculating the heat distribution and material properties of each printing area to achieve precise cooling of local areas and avoid deformation caused by heat accumulation. The cooling time is controlled within 5 to 10 seconds.

[0138] S5: Post-molding processing.

[0139] S51: Perform all-round automated surface inspection on the 3D printed parts after molding, including surface smoothness, interlayer bonding strength and material uniformity, with an inspection accuracy of 0.01 mm, and record the inspection results for archiving.

[0140] S52: Based on the surface inspection results, surface defects are partially repaired through automated processing equipment, such as laser repair with a laser power of 25 watts or micron-level polishing (polishing accuracy of 0.001 mm) to ensure that the surface quality of the final product meets industrial standards.

[0141] S53: After the surface treatment is completed, the printed parts are tested for physical and mechanical properties, including tensile strength (>50 MPa), hardness (>80 Shore hardness) and wear resistance, to ensure that the printed parts meet the expected use requirements, and the test result error does not exceed 5%.

[0142] During the printing process, the material supply and printing speed are highly matched. The surface of the printed 3D parts is smooth, and the interlayer bonding strength exceeds 35 MPa. After surface treatment, the surface finish reaches Ra1.5 microns.

[0143] Example 2

[0144] The other steps are the same as those in Example 1.

[0145] In Example 2, except for step S4, a BeagleBone Black single-board computer equipped with an A* algorithm is used to optimize the print head path. When printing complex geometric shapes, the print head moves at a speed of 25 mm per second by calculating the minimum cost path, which greatly reduces the printing time.

[0146] In Example 2, except for step S43, a dual-channel cooling system is used, the cooling temperature of the first channel is set to 25° C., and the temperature of the unprinted area of ​​the second channel is maintained at 30° C. to ensure that the printed part is not deformed due to excessive temperature difference.

[0147] After molding, the 3D printed parts are surface treated and quality inspected by the TrumpfTruLaser1030 equipment. The surface smoothness of the final product meets industrial standards. The mechanical properties test results show that the tensile strength is 55 MPa and the hardness is 85 Shore hardness, which meets the requirements of high-strength applications.

[0148] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A 3D printing optimization process based on melting of granular materials, characterized in that: The steps include: S1. Pretreatment of pellets Preheat the granular material to be printed to ensure that the granular material has a consistent temperature and control the humidity according to the material characteristics; S2. Quantitative supply of pellets The granular material is accurately fed into the printer according to the set supply amount through the intelligent feeding device; S3. Melting of pellets A multi-stage heating device is used to heat and melt the granular material layer by layer; S4. Layer by layer molding By precisely controlling the movement path and speed of the print head, the molten material is deposited layer by layer and quickly solidified in combination with the cooling system; S5. Post-molding processing Perform necessary surface treatment on the formed 3D printed parts.

2. A 3D printing optimization process based on melting of granular materials according to claim 1, characterized in that: in, Step S1 specifically includes the following steps: S11. Using a hot air drying device with timing and temperature control functions, the pellets were preheated at a constant temperature of 70 ° C for 3 hours; S12. Use a humidity control system and a precise humidity sensor to monitor and maintain the humidity of the pellet storage environment between 6% and 7% in real time. When the humidity exceeds the set range, the dehumidification or humidification equipment is automatically started to adjust the humidity; S13. Automatically screen the granular material, set the screening particle size to 0.5 mm to 2 mm, and remove particles that do not meet the requirements.

3. The 3D printing optimization process based on melting of granular materials according to claim 1, characterized in that: in, The S2 step specifically includes the following steps: S21. A high-precision flow sensor is provided in the feeding device, and the feeding rate is automatically adjusted through a closed-loop control system in real time feedback; S22. The feed amount is precisely adjusted through a closed-loop control system to maintain a fluctuation range of the feed amount within ±0.5 g; S23. A constant temperature heating module is integrated in the feeding device to keep the temperature of the pellets constant at 70°C±2°C during the conveying process.

4. The 3D printing optimization process based on melting of granular materials according to claim 1, characterized in that: in, The S3 step specifically includes the following steps: S31. The multi-stage heating device is divided into at least three independently controlled heating zones, and the temperature settings of each zone are 180 ° C, 210 ° C, and 240 ° C, respectively, and the temperature is automatically adjusted according to the melting point of the granular material and the target printing layer thickness; S32. Use temperature gradient control technology during the melting process to gradually increase the temperature; S33. Equipped with a dynamic temperature adjustment module to detect and adjust the temperature distribution of the heating area in real time.

5. The 3D printing optimization process based on melting of granular materials according to claim 1, characterized in that: in, The S4 step specifically includes the following steps: S41. Use a precision computer numerical control system to monitor the movement path of the print head in real time and reduce printing time through a path optimization algorithm; S42. During the molding process, the nozzle movement speed and material extrusion rate are dynamically adjusted according to the real-time calculated printing layer thickness and geometry to ensure that the interlayer bonding strength reaches more than 30 MPa and the surface finish reaches Ra1.6 microns; S43. Use efficient air cooling or water cooling system to quickly cure each printed layer within 5 seconds, and the cooling temperature is controlled between 20°C and 30°C. Start the next layer printing immediately after curing.

6. The 3D printing optimization process based on melting of granular materials according to claim 1, It is characterized in that in, Step S5 specifically includes the following steps: S51. Perform all-round automated surface inspection on the 3D printed parts after molding, including surface smoothness, interlayer bonding strength and material uniformity, with an inspection accuracy of 0.01 mm, and record and archive the inspection results; S52. Based on the surface inspection results, local repair of surface defects is performed through automated processing equipment; S53. After surface treatment, the printed parts are tested for physical and mechanical properties, including tensile strength (>50 MPa), hardness (>80 Shore A hardness), and wear resistance.

7. The 3D printing optimization process based on melting of granular materials according to claim 2, characterized in that: in, The humidity control system of step S12 further includes: S121. Set up an environmental humidity monitoring module to monitor the humidity changes in the printing room in real time, with a sampling interval of 10 seconds, and automatically adjust the storage environment humidity of the granular material through the central control system, and control the humidity fluctuation within ±1%; S122. When the humidity exceeds the set range, the dehumidification or humidification equipment is automatically started to quickly return the ambient humidity to between 6% and 7%.

8. The 3D printing optimization process based on melting of granular materials according to claim 3, characterized in that: in, The closed-loop control system in step S22 includes: S221. Equipped with a feeding rate feedback module, which detects and feeds back the feeding rate to the control system. The system automatically adjusts the feeding amount according to real-time data, and the feeding rate error does not exceed ±0.2 grams; S222. The feed rate feedback module is synchronized with the movement path of the print head.

9. The 3D printing optimization process based on melting of granular materials according to claim 4, characterized in that: in, The dynamic temperature adjustment module of step S33 further includes: S331. Equipped with infrared temperature sensor, used to monitor the temperature distribution of pellets in the melting process in real time, and adjust the power of each heating area through data feedback control system. S332. The temperature sensor data is fed back to the control system in real time to adjust the power output of each heating area.

10. The 3D printing optimization process based on melting of granular materials according to claim 5, It is characterized in that in, The efficient cooling system in step S43 further comprises: S431. Use dual-channel cooling technology, one channel is used to quickly cool the printed layer surface, and the other channel is used to cool the unprinted area; S432. The cooling system is linked with the printing path planning system to dynamically adjust the cooling wind speed and cooling path by calculating the heat distribution and material properties of each printing area.

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