Process and equipment for high-speed 3D printing of high-toughness integral roller

Abstract

The invention discloses a process and equipment for high-speed 3D printing of a high-toughness integral roller, and particularly relates to the technical field of high-speed additive manufacturing molding, and the process comprises the following steps: preparing a metal material for later use; the sealing cavity is vacuumized and filled with inert gas; adjusting the equipment and the device to an initial station; melting atomized metal and controlling deposition; stirring, rubbing and extruding the deposition layer; carrying out micro-forging extrusion rolling; processing the model and performing three-dimensional printing; printing layer by layer; monitoring the printing process; and after printing is finished, closing the equipment, cooling and taking down the roller. According to the technology and equipment for high-speed 3D printing of the high-toughness integral roller, by means of the metal spray deposition forming technology, molten metal liquid drops impact the deposition supporting plate at a high speed, mechanical crushing is generated on the deposition surface, rapid solidification is achieved at the ultrahigh cooling rate, and ultra-fine grains and fine and uniform isometric crystal or non-dendritic crystal structures are formed; the material strength is improved, the toughness is improved, and the service performance of the high-toughness integral roller working layer is effectively improved.

Description

Technical Field

[0001] This invention relates to the field of high-speed additive manufacturing technology, and in particular to a high-speed 3D printing process and equipment for high-strength and tough integral rolls. Background Technology

[0002] Rolls are core components of rolling mills in the steel and non-ferrous metals processing industries, and are divided into integral rolls and composite rolls. Integral rolls are made from a single material through casting or forging, and their microstructure and properties are controlled through casting, forging, and heat treatment processes. In traditional manufacturing processes, static casting is difficult to precisely control the internal microstructure and properties, and is prone to defects such as porosity and shrinkage. Forging is difficult to manufacture rolls with complex shapes, easily leads to coarse grains, and has high mold costs and poor economic efficiency for small-batch production. At the same time, both processes have the problems of long production cycles (requiring several weeks or even months) and low material utilization (usually less than 60%).

[0003] While existing metal 3D printing technologies (such as high-energy beam additive manufacturing using lasers and plasma) can achieve integrated manufacturing of complex structures, they have significant drawbacks:

[0004] First, the deposition efficiency is low. The additive efficiency of technologies such as laser is only 30 to 1500 grams per hour, while the efficiency of electric arc wire can reach 3 to 5 kg per hour, but it still cannot meet the one-time additive requirements of large-size rolls.

[0005] Secondly, it relies on high-cost spherical metal powders or wires, and the preparation of raw materials is complex and the types are limited;

[0006] Third, the printed material has a cast structure, which has limited strength and fatigue life and insufficient fatigue resistance. If it is forged later, the geometry will be destroyed, losing the rapid manufacturing advantage of 3D printing. Furthermore, it is difficult to eliminate porosity and unfused defects, which restricts its promotion and application in the field of high-end rolls. Summary of the Invention

[0007] The main objective of this invention is to provide a high-speed 3D printing process and equipment for high-strength and tough integral rolls, which can effectively solve the problems involved in the background art.

[0008] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0009] A high-speed 3D printing process for high-strength and high-toughness integral rolls includes the following steps:

[0010] S1: Prepare and melt metal materials, prepare them into granules or powders, and load them into a feeder for later use;

[0011] S2: Combine the upper and lower sealing cavities and tighten them, then fill with inert protective gas after evacuation;

[0012] S3: Adjust the deposition tray to the 3D printing starting position and start the Z-axis transmission system and Y-axis rotary axis transmission mechanism;

[0013] S4: Activate the X-axis reciprocating movement mechanism to move the inert gas atomizer, stirring friction device and high-frequency micro forging device to the 3D printing starting position of the deposition tray;

[0014] S5: Start the automatic metal particle conveyor, send the metal particles into the metal melting crucible for heating and melting, and the molten metal is atomized into a jet by the atomizer and continuously sprayed onto the deposition plate. Start the Y-axis rotating shaft (21) to rotate in the opposite direction at a certain speed. Adjust the crucible reciprocating movement distance and the metal particle feeding speed to control the diameter of the roller deposition layer and the flow rate of the molten metal spray.

[0015] S6: During the continuous jet deposition process, the Y-axis rotates in the opposite direction at a certain speed. When the Y-axis rotates the jet additive layer sprayed onto the deposition layer support plate of the designed thickness to the bottom of the stirring friction device, the stirring friction motor is started, which drives the friction disk to rotate and insert into the deposition layer to perform friction, extrusion and stirring on the deposition layer.

[0016] S7: When the friction stir extrusion layer rotates in the opposite direction to the underside of the high-frequency micro forging device, start the micro forging motor to drive the high-frequency micro forging device to apply pressure to the friction stir extrusion layer for micro forging and rolling.

[0017] S8: The equipment control system processes the 3D CAD model of the roll into layers and slices to generate CNC code, set the forming path and motion trajectory, and perform XYZ 3D motion printing of the roll.

[0018] S9: After the first layer is printed, start the Z-axis lifting transmission system to move the deposition tray downward layer by layer, repeat the metal atomized jet deposition, friction stir extrusion cladding additive manufacturing and micro forging extrusion until the required additive height is reached;

[0019] S10: During the printing process, the temperature of the deposited additive layer is monitored by a thermometer, the printing process is monitored by a camera, and the air pressure monitoring system monitors and adjusts the inert gas pressure in the sealed cavity.

[0020] S11: After printing is complete, turn off the relevant power supply, and after cooling, turn off the vacuum pump and inert gas valve, loosen the bolts to open the sealing cavity, and remove the printed roll.

[0021] Preferably, the size of the particles or powder in S1 is 0.05 to 6 mm.

[0022] Preferably, in step S2, the vacuum is evacuated to 0.5 to 1 atmosphere, and an inert protective gas is introduced to 0.5 to 1 atmosphere.

[0023] Preferably, the material of the 3D printed high-strength and tough integral roll is alloy ductile iron, nickel-chromium-molybdenum alloy cast iron, improved nickel-chromium-molybdenum alloy cast iron, high-chromium cast iron, cast steel, mold steel for hot rolling rolls, mold steel for cold rolling rolls, high-chromium cast steel, semi-steel, high-speed steel, and particle-reinforced metal matrix composite material.

[0024] Preferably, the material of the 3D printed high-strength and tough integral roll can be directly used to cut granules from the roll.

[0025] Preferably, the jet deposition rate of the 3D printed high-strength and tough integral roll in S5 is 10 kg to 400 kg / h.

[0026] Preferably, in S6, the helical teeth on the friction disk are inserted to a thickness of 0.5 to 1.0 times the thickness of the semi-solid metal atomized jet deposition layer, and the shoulder of the friction disk is kept pressed against the top of the deposition layer.

[0027] Preferably, in S9, the molten metal is sprayed onto the deposition layer plate in the form of a metal atomized jet through an atomizer, and the thickness is 0.5 to 5 mm.

[0028] Preferably, in step S10, a mobile infrared thermometer with a fixed temperature measurement distance installed on the inner wall of the sealed cavity is used to monitor the temperature synchronously at the same distance, and multiple high-speed monitoring cameras are installed at different parts of the inner wall of the sealed cavity for three-dimensional monitoring.

[0029] A high-speed 3D printing equipment for high-strength and tough integral rolls, wherein the equipment uses the high-speed 3D printing process for high-strength and tough integral rolls described in any one of the above claims to prepare high-strength and tough integral rolls.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] 1. The high-speed 3D printing high-strength and tough integral roll process and equipment provided by the present invention uses a metal jet deposition forming process to directly spray molten metal onto a deposition plate. During the jet forming process, molten metal droplets impact the deposition plate at a high speed of 1 to 100 m / s, causing mechanical breakage on the deposition surface and rapid solidification at an ultra-high cooling rate of 103 to 107 °C / s, forming ultra-fine grains and fine, uniform equiaxed or non-dendritic structures with an average grain size of 1 to 100 μm, which is significantly better than the millimeter-level grains of traditional casting. This can significantly improve the material strength and toughness, and effectively improve the service performance of the working layer of the high-strength and tough integral roll.

[0032] 2. In this invention, the droplets undergo dynamic redistribution when they impact the deposition substrate, resulting in extremely short element diffusion time within the molten pool. Solute atoms do not have enough time to diffuse and agglomerate, making the alloy composition more uniform, reducing or eliminating segregation, and making it easier for metastable phases to appear. The degree of compositional segregation is reduced by more than 80% compared to traditional casting.

[0033] 3. During the preparation process of this invention, the excellent fine-grained structure and low segregation characteristics enable the comprehensive performance of the material (strength, toughness, and corrosion resistance) to exceed that of traditional casting and forging processes by more than 30%. This can eliminate the casting and forging processes of traditional rolls, reduce energy consumption by more than 30%, reduce the number of roll preparation steps, shorten the product production cycle, and improve productivity. It is particularly suitable for short-process, low-cost, high-quality, high-efficiency, and high-performance additive manufacturing of ultra-fine equiaxed crystal high-strength and tough integral roll components.

[0034] 4. The high-speed 3D printing process and equipment for high-strength and tough integral rolls provided by this invention utilizes the additive manufacturing process of melting metal particles or powder in a crucible followed by jet deposition. This reduces the complexity of technology and equipment involved in controlling the flow of liquid metal, simplifies control technology, and reduces energy consumption during prolonged heat preservation of the liquid metal in 3D printing. It also reduces contamination of the liquid metal by the melting of the refractory lining during prolonged heat preservation. This simplifies the metal 3D printing manufacturing process, significantly reduces energy consumption in production, and features a shorter process flow, lower cost, higher flexibility, and higher production efficiency.

[0035] 5. The high-speed 3D printing high-strength and tough integral roll process and equipment provided by the present invention can use metal alloy particles and powders of any shape and size, without being limited by particle shape, size and material type. Moreover, it can directly use roll chip granules, which has a wide range of applications and is convenient for industrial mass production. It can be produced by roll manufacturing companies or independently manufactured by specialized production companies, and the particle production cost is low.

[0036] 6. The high-speed 3D printing high-strength and tough integral roll process and equipment provided by this invention can directly use recycled overspray powder, realizing the value-added utilization of overspray powder in jet forming, reducing material waste, and improving material utilization rate. This significantly reduces production costs and achieves energy conservation and emission reduction.

[0037] 7. The high-speed 3D printing process and equipment for high-strength and tough integral rolls provided by this invention can efficiently, cost-effectively, and stably manufacture high-strength and tough integral rolls from various materials, including alloy ductile iron, nickel-chromium-molybdenum alloy cast iron, improved nickel-chromium-molybdenum alloy cast iron, high-chromium cast iron, cast steel, mold steel for hot rolling rolls, mold steel for cold rolling rolls, high-chromium cast steel, semi-steel, high-speed steel, and particle-reinforced metal matrix composites. It allows for precise control of material composition and microstructure according to the working conditions and performance requirements of different parts of the roll, achieving a gradient distribution of the material. It can obtain roll materials with stable and reliable equiaxed grain structure and forging properties. The manufactured high-strength and tough integral rolls possess excellent strength, toughness, wear resistance, and thermal crack resistance, effectively improving the quality of 3D-printed high-strength and tough integral roll products, thereby significantly improving the overall performance of the rolls. Their service life is 3 to 5 times longer than that of integral rolls manufactured using traditional processes.

[0038] 8. The high-speed 3D printing process and equipment for high-strength and tough integral rolls provided by this invention eliminates the need for mold manufacturing, allowing direct production based on a 3D model. This reduces production preparation time and processing steps, significantly shortening the roll manufacturing cycle. It achieves near-net-shape forming, reducing subsequent cutting operations (saving 20%–50% of material), increasing material utilization to over 90%, reducing material waste, lowering production costs, and meeting the needs of sustainable development.

[0039] 9. The high-speed 3D printing integral roll process and equipment provided by this invention can quickly respond to market demands for high-performance, personalized, and customized rolls, enabling rapid customization and providing high-quality roll products for industries such as steel and non-ferrous metals. This will help improve the quality and production efficiency of rolled products in my country, meeting the needs of high-end manufacturing for metal materials. It will also provide a reference and demonstration for the application of additive manufacturing technology in other high-end equipment manufacturing fields.

[0040] 10. The high-speed 3D printing process and equipment for high-strength and tough integral rolls provided by this invention applies additive manufacturing technology to roll manufacturing, and is expected to break through the limitations of traditional roll manufacturing processes, developing high-performance and customized roll products and processes. This is expected to solve the problems existing in traditional roll manufacturing processes, promote the technological upgrading and industrial transformation of the roll manufacturing industry, and improve the overall level and international competitiveness of my country's roll manufacturing. Attached Figure Description

[0041] Figure 1 This is a flowchart illustrating the overall process flow of the present invention.

[0042] Figure 2 This is a schematic diagram of the structure of the high-speed 3D printing high-strength and tough integral roll equipment of the present invention.

[0043] Figure 3This is a top view of the main structure of the present invention;

[0044] In the diagram: 1. Bracket, 2. Support sleeve, 3. Lower sealing cavity, 4. Hinged bolt, 5. Upper sealing cavity, 6. Metal atomizing jet, 7. Inert gas atomizer (atomizing nozzle), 8. Metal liquid guide pipe, 9. Stirring friction device, 10. Stirring friction motor, 11. Crucible electromagnetic heating induction coil, 12. Metal melting crucible, 13. Metal liquid, 14. Lifting ring, 15. Micro forging motor, 16. High-frequency micro forging device, 17. X-axis reciprocating movement Mechanism, 18. Sprayed additive layer, 19. Deposited layer support plate, 20. Rotary bearing, 21. Y-axis rotating shaft, 22. Air pressure regulating valve, 23. Z-axis lifting transmission system, 24. Z-axis lifting system, 25. Transmission sprocket, 26. Y-axis rotating shaft transmission mechanism, 27. Vacuum pump, 28. Piping, 29. Vacuum pump regulating valve, 30. Metal particle storage container, 31. Metal particles, 32. Automatic metal particle conveyor, 33. Particle conveying pipe. Detailed Implementation

[0045] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0046] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0047] The high-speed 3D printing process for high-strength and tough integral rolls employs the following steps:

[0048] S1: According to the required composition of the working layer material of the high-strength and tough integral roll for 3D printing, prepare and melt the metal material, adjust and refine it according to the material composition requirements, and after reaching the required composition and temperature, prepare it into 0.05-6mm particles or powder. Load the prepared high-strength and tough integral roll material particles or powder with the required composition into the feeder for later use.

[0049] S2: Combine the upper sealing cavity 5 and the lower sealing cavity 3, and tighten them into a single unit using the hinge bolt 4. Start the vacuum pump 27 and open the vacuum regulating valve 29 to evacuate the sealing cavity. After the vacuum level reaches 0.5 to 1 atmosphere, close the vacuum regulating valve 29. Open the inert gas valve and fill the sealing cavity with inert protective gas. After the gas pressure reaches 0.5 to 1 atmosphere, close the inert gas valve to protect the metal atomized jet 6 and the 3D printed high-strength and tough integral roll from oxidation.

[0050] S3: Adjust the deposition tray to the 3D printing starting position: Start the Z-axis transmission system of the vertical high-speed 3D printing high-strength and tough integral roll equipment. Through the Z-axis lifting transmission system 23 of the high-speed 3D printing high-strength and tough integral roll equipment, the Z-axis lifting system 24 is rotated to move the deposition tray 19 upward to the starting position of jet deposition 3D printing. Start the Y-axis rotation shaft transmission mechanism 26. Through the transmission sprocket 25, the Y-axis rotation shaft 21 and the deposition tray 19 installed on the Y-axis rotation shaft 21 are driven to rotate in the opposite direction at a certain speed so that the jet deposition layer is evenly jetted and deposited onto the deposition tray 19.

[0051] S4: Preparation for 3D printing high-strength and tough integral roll: Start the X-axis reciprocating movement mechanism 17 installed on the upper part of the sealing cavity 5 of the vertical high-speed 3D printing high-strength and tough integral roll equipment, and move the inert gas atomizer 7 at the bottom of the metal melting crucible 12 installed on the upper sealing cavity 5, the stirring friction device 9 and the high-frequency micro forging device 16 installed on the upper sealing cavity 5 to the starting position of 3D printing on the deposition layer tray 19 on the Y-axis rotation axis 21 respectively;

[0052] S5: Metal molten spray deposition: Start the automatic metal particle conveyor 32 to accurately feed the metal particles 31 in the metal particle storage container 30 into the metal molten crucible 12 through the particle conveying pipe 33 at the required flow rate. Start the power controller of the crucible electromagnetic heating induction coil 11 to heat the metal particles 31 in the metal molten crucible 12, so that the metal particles 31 melt into molten metal 13 layer by layer from bottom to top. The molten metal 13 flows out through the molten metal guide pipe 8 at the bottom of the metal molten crucible 12 and is atomized into a metal atomized jet 6 through the inert gas atomizer 7 below the molten metal guide pipe 8. It is continuously sprayed and deposited onto the deposition layer support plate 19. Start the Y-axis rotation shaft 21 to rotate in the opposite direction at a certain speed. By adjusting the reciprocating movement distance of the metal molten crucible 12, the diameter of the high-strength and tough roll deposition layer is achieved and controlled. By controlling the speed at which the metal particles 31 are fed into the metal molten crucible 12, the flow rate of the molten metal 13 is controlled.

[0053] S6: Eliminating metallurgical defects in the deposition layer and refining grains: During continuous jet deposition, the Y-axis rotation 21 rotates in the opposite direction at a certain speed. When the Y-axis rotation 21 rotates the jet additive layer 18, which is sprayed onto the deposition layer support plate 19 of the designed thickness, to the bottom of the stirring friction device, the stirring friction motor 10 in the vertical high-speed 3D printing high-strength and tough integral roll equipment is started, driving the friction disk under the stirring friction device 9 to rotate. The helical teeth on the friction disk are inserted into the current semi-solid metal atomized jet 6, which is 0.5 to 1.0 times the thickness of the deposition layer. The shoulder of the friction disk is kept pressed against the top of the deposition layer, and the deposition layer is rubbed, squeezed and stirred. Through the continuous movement and rotation of the friction disk in the deposition layer, the material in the deposition layer area undergoes severe plastic deformation, mixing and breaking dendrites, as well as thermoplastic melting and dynamic recrystallization. This achieves the refinement, homogenization and densification of the microstructure of the additive material and improves the interlayer bonding strength of the high-strength and tough integral roll additive layer.

[0054] S7: Improve the density and interlayer bonding of the additive layer: When the friction stir extrusion layer rotates in the reverse direction to the bottom of the high-frequency micro forging device, the micro forging motor 15 is started, driving the high-frequency micro forging device 16 to move up and down, and providing continuous pressure to the high-frequency micro forging device 16, so that the high-frequency micro forging device 16 moves synchronously along the friction forming trajectory, continuously and synchronously applying small pressure and high-frequency vibration micro forging and extrusion to the currently unsolidified friction stir extrusion layer, so that the friction extrusion stirring layer is forced to undergo plastic deformation, thereby effectively forging and crushing the branch crystals, refining the grains, improving the internal microstructure, effectively eliminating the pores, lack of fusion, and microcrack defects inside the high-strength and tough integral roll additive layer, improving the density of the additive layer metal material, and further improving the connection strength of the interlayer interface of the additive pass;

[0055] S8: 3D Motion Printing of High-Strength and Toughness Integral Rolls: The control system of the 3D printing high-strength and toughness integral roll equipment is activated by the control system of the vertical high-speed 3D printing high-strength and toughness integral roll equipment. The X-axis reciprocating movement mechanism 17, Y-axis rotation shaft transmission mechanism 26, and Z-axis lifting system 24 of the vertical high-speed 3D printing high-strength and toughness integral roll equipment are processed into layers according to the size and accuracy requirements of the 3D CAD model of the additive manufacturing high-strength and toughness integral roll component. The 3D CAD model of the high-strength and toughness integral roll is sliced ​​layer by layer to generate the CNC code required for each layer of 3D printing. The forming path planning and motion trajectory of the spatial 3D motion mechanism of the vertical high-speed 3D printing high-strength and toughness integral roll equipment are set, so that the vertical high-speed 3D printing high-strength and toughness integral roll equipment performs XYZ 3D motion to 3D print the high-strength and toughness integral roll.

[0056] S9: After the first layer of additive manufacturing is completed, the 3D printing control system will activate the Z-axis lifting transmission system 23, causing the Z-axis lifting system 24 to drive the sprayed additive layer 18 on the deposition layer support plate 19 above the Y-axis rotation axis 21 to move downward layer by layer at a uniform speed. The downward movement size each time is based on the thickness of each sprayed deposition layer. The subsequent layers are stacked in the additive manufacturing area, and the above operation is repeated according to the same path and additive spacing. The molten metal 13 in the metal melting crucible 12 is sprayed onto the deposition layer support plate 19 in the shape of a metal atomized jet 6 through the inert gas atomizer 7 below the molten metal guide pipe 8, with a thickness of 0.5 to 5 mm. The helical teeth on the friction disk below the stirring friction mechanism are inserted into the unstirred friction area between the current deposition layer and the previous additive manufacturing layer. The forging pressure and plastic rheological action between the shoulder of the friction disk and the previous deposition layer are applied. The process eliminates weak connection defects and non-welding defects at the inter-pass interface, allowing the interlayer interfaces to fuse and form a good metallurgical bonding interface. In the area to be added, a single layer of material is continuously deposited by repeated metal atomized jet 6 spraying. The material of the sprayed deposited layer is repeatedly stirred, frictionally extruded, and stacked, and the frictionally extruded and stacked additive layer is micro-forged and micro-extrusion rolled. This transforms the anisotropic cast columnar / dendritic crystals into uniform and ultra-fine equiaxed crystals without the texture that easily occurs in traditional rolling, achieving strength and toughness. Ultimately, it achieves the forging structure and performance of the forging. In this way, multi-layer material stacking additive is achieved until the last layer is deposited, reaching the additive height required for a high-strength and tough integral roll, and obtaining the required 3D printed high-strength and tough integral roll component shape with a fine and uniform structure. By repeating the above steps, a 3D printed high-strength and tough integral roll component with a fine and uniform structure and all metallurgical bonding interfaces can be achieved.

[0057] S10: During the 3D printing manufacturing process, a far-infrared thermometer with a fixed temperature measurement distance and a mobile position installed on the inner wall of the sealed cavity is used to monitor the temperature of the additive layer sprayed onto the high-strength and tough integral roll at the same distance and synchronously. Multiple high-speed monitoring cameras are also installed at different parts of the inner wall of the sealed cavity to provide three-dimensional monitoring of the entire 3D printing process of the high-strength and tough integral roll within the sealed cavity. During the entire 3D printing process, the inert gas pressure in the sealed cavity is also monitored through an air pressure monitoring system. Once the air pressure in the sealed cavity exceeds the rated value, the air pressure regulating valve 22 will automatically open to regulate the inert gas pressure in the sealed cavity.

[0058] S11: After printing is completed, turn off the electromagnetic heating power supply of the crucible. After the 3D printed high-strength and tough integral roll cools down, turn off the vacuum pump 27 and the inert gas valve to end the 3D printing preparation process. Loosen the hinge bolt 4, open the sealing cavity, and lift the metal melting crucible 12, the metal liquid guide pipe 8, the inert gas atomizer 7, the stirring friction device 9, and the high-frequency micro forging device 16 on the upper sealing cavity 5 upward. Start the Z-axis lifting mechanism of the vertical high-speed 3D printing high-strength and tough integral roll equipment to lift the Y-axis rotating shaft 21, the deposition layer support plate 19, and the 3D printed high-strength and tough integral roll upward. Remove the 3D printed high-strength and tough integral roll from the deposition layer support plate 19 to finally obtain the 3D printed high-strength and tough integral roll component of the required size and shape.

[0059] Furthermore, the materials used for 3D-printed high-strength and tough integral rolls include alloy ductile iron, nickel-chromium-molybdenum alloy cast iron, improved nickel-chromium-molybdenum alloy cast iron, high-chromium cast iron, cast steel, mold steel for hot rolling rolls, mold steel for cold rolling rolls, high-chromium cast steel, semi-steel, high-speed steel, and particle-reinforced metal matrix composites.

[0060] Furthermore, the material of the 3D printed high-strength and tough integral roll can be directly used to cut granular materials;

[0061] Furthermore, the jet deposition rate of the 3D-printed high-strength and tough integral roll is 10 kg to 400 kg / h.

[0062] Furthermore, the vertical high-speed 3D printing high-strength and tough integral roll equipment of the present invention specifically includes metal smelting equipment, atomization preparation equipment for metal powder particles, metal particle storage and automatic conveying equipment, vertical high-speed 3D printing high-strength and tough integral roll equipment, equipment control and 3D printing software system, and inert gas supply system.

[0063] An X-axis reciprocating moving mechanism 17 is installed on the upper part of the upper sealing cavity 5. A metal melting crucible 12 is installed on the X-axis reciprocating moving mechanism 17. An electromagnetic heating induction coil 11 is installed on the outside of the metal melting crucible 12. A molten metal guide pipe 8 is installed at the bottom of the molten metal crucible 12. An inert gas atomizer 7 is installed below the molten metal guide pipe 8.

[0064] The stirring friction device 9 is installed on the side of the metal melting crucible 12 in the upper part of the upper sealing cavity 5 in the opposite direction of rotation along the Y direction. The stirring friction motor 10 is installed on the stirring friction mechanism. The high frequency micro forging device 16 is installed on the side of the stirring friction device 9 in the opposite direction of rotation along the Y direction.

[0065] The micro forging motor 15 is mounted on the high-frequency micro forging device 16;

[0066] The deposition plate 19 is mounted on the Y-axis rotation shaft 21. The deposition plate 19 has an inert gas atomizer 7 depositing a jet additive layer 18. The Y-axis rotation shaft 21 is mounted on the Z-axis lifting mechanism. A drive sprocket 25 is mounted on the lower part of the Y-axis rotation shaft 21. The Y-axis rotation shaft drive mechanism 26 is mounted on the Z-axis lifting system 24. The Y-axis rotation shaft drive mechanism 26 drives the Y-axis rotation shaft 21 and the deposition plate 19 mounted on the Y-axis rotation shaft 21 to rotate in the Y direction through the drive sprocket 25.

[0067] The Z-axis lifting system 24 can drive the deposition plate 19 on the Y-axis rotating shaft 21 to move up and down in the Z direction. A bracket 1 is installed on the Z-axis lifting system 24, and the lower sealing cavity 3 is installed on the bracket 1. A support sleeve 2 is installed on the lower sealing cavity 3, and rotating bearings 20 are installed on the inner surfaces of both ends of the support sleeve 2. A vacuum pump 27, a vacuum pump regulating valve 29, and a vacuum pump connecting pipe are installed below the lower sealing cavity 3. A metal particle storage container 30 is installed next to the exterior of the vertical high-speed 3D printing high-strength and tough integral roll equipment. The metal particle storage container 30... The surface is equipped with an automatic metal particle conveyor 32 and a particle conveying pipe 33. The upper sealing cavity 5 and the lower sealing cavity 3 are fastened and sealed together by a hinge bolt 4. A pressure regulating valve 22 is installed on the lower part of any side of the lower sealing cavity 3. A lifting ring 14 is installed on the upper part of the upper sealing cavity 5 to facilitate the lifting of the upper sealing cavity 5. A synchronous far-infrared thermometer is installed inside the sealing cavity. A high-speed monitoring camera is installed on different parts of the inner wall of the sealing cavity. The vertical high-speed 3D printing high-strength and tough integral roll equipment is equipped with an equipment control and 3D printing software system on any side.

[0068] Furthermore, the metal melting crucible 12 is made of graphite, silicon carbide, or a mixture of silicon carbide and graphite, and the heater of the metal melting crucible 12 is a medium-frequency electromagnetic induction heating coil or a high-frequency electromagnetic induction heating coil.

[0069] Furthermore, the friction stir motor 10 is a servo motor or a variable frequency speed control motor;

[0070] Furthermore, the micro-forging motor 15 is a servo motor or a variable frequency speed control motor;

[0071] Furthermore, the motor of the X-axis reciprocating movement mechanism 17 is a servo motor or a variable frequency speed control motor;

[0072] Furthermore, the drive motor of the Z-axis lifting system 24 is a servo motor, a stepper motor, or a variable frequency speed control motor;

[0073] Furthermore, the drive motor of the Y-axis rotation 21 is a servo motor or a variable frequency speed control motor;

[0074] Furthermore, the rotational speed of the stirring friction device 9 is 50 to 3000 rpm / min, the axial pressure is 5 kN to 400 kN, and the downward pressure is 0 to 5 mm.

[0075] Furthermore, the toothed friction disc has 1 to 9 spiral ribs on its flat surface. The height of the spiral ribs on the shoulder plane is 1 to 6 mm, the width of the top of the spiral ribs is 1 to 3 mm, and the inclination angle of the spiral ribs is 5° to 15°.

[0076] Furthermore, the inert protective gas is nitrogen, argon, or a mixture of nitrogen and argon.

[0077] The high-speed 3D printing process and equipment for high-strength and tough integral rolls provided by this invention have a simple structure, reasonable design, low equipment investment cost, and are convenient for processing, manufacturing, and installation. The equipment is easy to operate, highly intelligent, efficient, and produces high-quality rolls. When using this invention to manufacture rolls using 3D printing, the process is simple and the flow is short. Compared with existing high-energy beam 3D printing processes, it reduces the difficulty and cost of the process. The 3D printing production efficiency is as high as 10kg to 400kg / h, which can meet the needs of 3D printing production of thick, heavy, high-strength and tough integral rolls and the remanufacturing of waste rolls.

[0078] In order to produce metal particles or powder, this equipment naturally includes metal molten metal smelting equipment, intermediate ladle for receiving molten metal, inert gas atomization equipment for preparing metal particles and powder, etc. However, since these can all be assembled using conventional equipment and components, they can be external devices or integrated into the equipment system of this invention, and therefore will not be described here.

[0079] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A high-speed 3D printing process for high-strength and high-toughness integral rolls, characterized in that, Includes the following steps: S1: Prepare and melt metal materials, process them into granules or powders, and load them into a feeder for later use; S2: Combine the upper sealing cavity (5) and the lower sealing cavity (3) and tighten them with the hinge bolt (4). Use the vacuum pump (27) to evacuate to 0.5 to 1 atmosphere through the pipeline (28) and the vacuum pump regulating valve (29), and then fill with inert protective gas to 0.5 to 1 atmosphere. S3: Adjust the deposition layer tray (19) to the 3D printing starting position, and start the Z-axis lifting transmission system (23) and the Y-axis rotating shaft transmission mechanism (26); S4: Start the X-axis reciprocating movement mechanism (17) to move the inert gas atomizer (7), stirring friction device (9) and high frequency micro forging device (16) to the 3D printing starting position of the deposition layer tray (19); S5: Start the automatic metal particle conveyor (32), and send the metal particles (31) from the metal particle storage container (30) into the metal melting crucible (12) through the particle conveying pipe (33). The crucible is heated and melted by the electromagnetic heating induction coil (11). The molten metal (13) is atomized into a metal atomized jet (6) by the inert gas atomizer (7) and continuously sprayed onto the deposition layer tray (19). Start the Y-axis rotating shaft (21) to rotate in the opposite direction at a certain speed. The diameter of the roller deposition layer and the flow rate of the molten metal spray are controlled by adjusting the reciprocating movement distance of the metal melting crucible (12) and the feeding speed of the metal particles (31). S6: During the continuous jet deposition process, the Y-axis rotation shaft (21) rotates in the opposite direction at a certain speed. When the jet additive layer (18) sprayed onto the deposition layer support plate (19) of the designed thickness is rotated by the Y-axis rotation shaft (21) to the bottom of the stirring friction device, the stirring friction motor (10) is started, which drives the friction disk of the stirring friction device (9) to rotate and insert into the deposition layer, and to perform friction, extrusion and stirring on the deposition layer. S7: When the friction stir extrusion layer rotates in the opposite direction to the underside of the high frequency micro forging device, start the micro forging motor (15) and drive the high frequency micro forging device (16) to apply pressure to the friction stir extrusion layer for micro forging and rolling. S8: The equipment control system processes the 3D CAD model of the roll into layers and slices to generate CNC code, set the forming path and motion trajectory, and perform XYZ 3D motion printing of the roll. S9: After the first layer is printed, start the Z-axis lifting transmission system (23) and move the deposition layer tray (19) downward layer by layer. Repeat the metal atomization jet (6) spray deposition, stirring friction extrusion stacking additive and micro forging extrusion until the required additive height is reached. S10: During the printing process, the temperature is monitored synchronously at the same distance by a far-infrared thermometer installed on the inner wall of the sealed cavity with a fixed temperature measurement distance. Multiple high-speed monitoring cameras are installed at different parts of the inner wall of the sealed cavity for three-dimensional monitoring. The air pressure monitoring system monitors and adjusts the inert gas pressure in the sealed cavity through the air pressure regulating valve (22). S11: After printing is complete, turn off the relevant power supply, and after cooling, turn off the vacuum pump (27) and the inert gas valve. Loosen the hinge bolt (4) to open the sealing cavity and remove the printed roll.

2. The high-speed 3D printing process for high-strength and high-toughness integral rolls according to claim 1, characterized in that: The particle or powder size described in S1 is 0.05 to 6 mm.

3. The high-speed 3D printing process for high-strength and high-toughness integral rolls according to claim 1, characterized in that: As described in S2, the vacuum is evacuated to 0.5 to 1 atmosphere, and then filled with inert protective gas to 0.5 to 1 atmosphere.

4. The high-speed 3D printing process for high-strength and high-toughness integral rolls according to claim 1, characterized in that: The 3D-printed high-strength and tough integral rolls are made of alloy ductile iron, nickel-chromium-molybdenum alloy cast iron, improved nickel-chromium-molybdenum alloy cast iron, high-chromium cast iron, cast steel, mold steel for hot rolling rolls, mold steel for cold rolling rolls, high-chromium cast steel, semi-steel, high-speed steel, and particle-reinforced metal matrix composite materials.

5. The high-speed 3D printing process for high-strength and high-toughness integral rolls according to claim 1, characterized in that: The material of the 3D printed high-strength and tough integral roll can be directly used to cut granular materials.

6. The high-speed 3D printing process for high-strength and high-toughness integral rolls according to claim 1, characterized in that: The jet deposition rate of the 3D printed high-strength and tough integral roll described in S5 is 10 kg to 400 kg / h.

7. The high-speed 3D printing process for high-strength and high-toughness integral rolls according to claim 1, characterized in that: The helical teeth on the friction disk described in S6 are inserted into the semi-solid metal atomized jet (6) at a thickness of 0.5 to 1.0 times, and the shoulder of the friction disk is pressed against the top of the deposition layer.

8. The high-speed 3D printing process for high-strength and high-toughness integral rolls according to claim 1, characterized in that: The molten metal (13) described in S9 is sprayed onto the deposition plate (19) in the shape of a metal atomized jet (6) by an inert gas atomizer (7) with a thickness of 0.5 to 5 mm.

9. The high-speed 3D printing process for high-strength and high-toughness integral rolls according to claim 1, characterized in that: As described in S10, a mobile far-infrared thermometer with a fixed temperature measurement distance installed on the inner wall of the sealed cavity is used to monitor the temperature synchronously at the same distance. Multiple high-speed monitoring cameras are installed at different parts of the inner wall of the sealed cavity for three-dimensional monitoring.

10. A high-speed 3D printing equipment for high-strength and high-toughness integral rolls, characterized in that: The rolling mill equipment is used to prepare high-strength and high-toughness integral rolling mills using the high-speed 3D printing high-strength and high-toughness integral rolling mill process described in any one of claims 1-9.

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