CN114474717B - A powder bed cladding additive manufacturing device and method for interstellar base construction - Google Patents

Abstract

A powder bed cladding additive manufacturing device and method for constructing an interstellar base belong to the technical field of manufacturing of building materials of the interstellar base, and the specific scheme is as follows: a powder bed cladding additive manufacturing device for constructing a star base comprises a printing head, a printing head actuating system, a powder bed platform and an automatic light tracing system, wherein the printing head is controlled by the printing head actuating system to keep the printing head above the powder bed platform and vertical to the upper surface of the powder bed platform, star soil is laid on the powder bed platform, and the automatic light tracing system converges the energy of sunlight on the printing head.

Description

A powder bed cladding additive manufacturing device and method for the construction of an interstellar base

technical field

The invention belongs to the technical field of building materials for extraterrestrial bases, and in particular relates to a powder bed cladding additive manufacturing device and method for the construction of interstellar bases, which is especially suitable for interstellar soil-based materials such as lunar soil and Martian soil, and can be applied to extraterrestrial bases Building materials products are constructed in situ.

Background technique

Astronauts, military equipment and scientific instruments must survive and serve in extreme alien environments. Alien bases can provide key support platforms for human beings to carry out long-term space exploration. As an important part of the huge and complex alien base system engineering, the construction (structure) of the alien base requires a lot of engineering materials from the start of construction to the operation and maintenance, and the cost of satellite-to-ground launch is huge. Therefore, how to greatly reduce the dependence of engineering construction on the earth's launch load has become a major problem that needs to be solved urgently to achieve long-term sustainable space exploration.

In-suit resource utilization (ISRU) technology refers to the collection and processing of local resources discovered by humans (or robots) during space exploration. Alien soil is a natural resource in the form of silicate minerals as the main component, and has the potential and advantages of in-situ resource utilization and engineering material utilization. The technology of in situ resource utilization can greatly reduce the dependence of alien development activities on earth materials, reduce the transportation cost required for the construction and operation of alien bases, and improve the sustainability of related tasks. With the construction of alien bases on the agenda, the utilization of engineering materials such as alkali excitation, self-propagation, and light curing of alien soils is being explored at home and abroad, but they still rely heavily on a large number of additives emitted by the earth to achieve normal temperature or high temperature consolidation. Related technical methods still have problems such as insufficient consideration of the extraterrestrial environment and inability to prepare key raw materials in situ. In addition, the extraterrestrial environment has inexhaustible solar energy resources, which can be used as the main energy for in-situ resource utilization and engineering material utilization, thereby further reducing dependence on earth resources, improving energy conversion efficiency, simplifying the complexity of the system, and improving the The sustainability of the construction, operation and maintenance of the star base is guaranteed. At present, NASA in the United States and ESA in the European Union have initially verified the feasibility of direct sintering of lunar soil and fire soil by solar concentrators. However, there are still key defects in the material molding process of related technical routes, which leads to the need to improve the performance of formed products. Therefore, in-situ resource utilization technology with higher achievability and complete forming process still needs to be developed.

Additive manufacturing (AM) technology is based on the three-dimensional digital model, using "layer-by-layer manufacturing, layer-by-layer stacking" to realize the processing and manufacturing of parts. Additive manufacturing technology has the advantages of "more, faster, more economical" and "zero-skill" manufacturing, which is very suitable for the manufacturing needs of complex configuration parts and extreme environmental conditions. Powderbed fusion (PBF) refers to an additive manufacturing technique that uses thermal energy to selectively fuse the powder bed area, and has been widely used in industrial production activities. At present, many scholars have carried out research on selective powder bed cladding of extraterrestrial soil, but the use of traditional heat sources (laser, microwave, electron beam, etc.) to carry out selective cladding requires relatively large power and the reliability of complex systems in extreme environments lower issues. Therefore, more direct, efficient and low-power additive manufacturing methods need to be considered.

There are abundant extraterrestrial soil resources and abundant solar energy resources on the surface of aliens. Using direct focused sunlight as the heat source to carry out additive manufacturing of extraterrestrial soil powder bed cladding has the following significant advantages: First, it is highly in line with the concept of in-situ resource utilization, and maximizes the use of in-situ abundant raw material resources and solar energy resources; Second, The energy utilization efficiency is high, the energy conversion method is direct, and the system is simple and reliable; third, it solves the problems of lack of infrastructure and difficult supply of industrial raw materials in the early development activities of the alien environment. Different from traditional additive manufacturing methods, the environment of solar 3D printing is highly open, the influencing factors change dynamically, and the forming process is easily disturbed by the outside world. Therefore, relevant devices and processes are required to have the characteristics of sensing changes and dynamic adjustment. The existing sunlight-based fusion sintering 3D printing process still lacks the function of real-time regulation of the printing process. Obviously, using directly focused sunlight as a heat source to carry out powder bed cladding additive manufacturing and real-time regulation of the additive manufacturing process considering the impact of environmental changes can significantly improve the applicability of the additive manufacturing method using solar energy as a heat source, and It can be used in the fields of in-situ construction of alien bases and material utilization of interstellar soil in-situ engineering, providing key technical support for alien development activities with a high degree of in-situ supply of energy resources.

SUMMARY OF THE INVENTION

The first object of the present invention is to provide a powder bed cladding additive manufacturing device for the construction of an interstellar base in order to solve the problem of excessive dependence on the transportation of earth resources during the construction of an alien base in the prior art.

A second object of the present invention is to provide a method for building a powder bed cladding additive manufacturing device using an interstellar base.

To achieve the above object, the technical scheme adopted by the present invention is as follows:

A powder bed cladding additive manufacturing device for interstellar base construction, comprising a print head, a print head actuation system, a powder bed platform and an automatic light tracking system, wherein the print head is controlled by the print head actuation system to keep the print head at the Above the powder bed platform and perpendicular to the upper surface of the powder bed platform, the interstellar soil is laid on the powder bed platform, and the automatic light tracking system concentrates the energy of sunlight on the print head.

A method for in-situ utilization of solar energy to realize additive manufacturing of interstellar soil resource powder bed cladding by using the device, characterized in that the in-situ focused solar energy is used as a thermal radiation type point heat source print head to drive the plane movement of the print head, and select heating The interstellar soil-based powder bed is completely melted at high temperature, then cooled and solidified, and powder is spread layer by layer, and the powder bed cladding of interstellar soil resources can be directly realized by solar energy. Specifically include the following steps:

Step 1. Material pretreatment: sieve the powder material;

Step 2: Loading and leveling: add the pre-treated powder material to the powder bed platform, scrape the surface of the powder to form a powder bed, and adjust the surface of the powder bed to the focal plane of the heat source;

Step 3. Preheating: preheating the powder bed platform to the point where the surface temperature of the powder bed is not lower than 15%-20% of the melting temperature of the material;

Step 4. Adjust the focus state of the spot: adjust the surface of the powder bed to a suitable relative position with the spot, so as to adjust the energy level and spot size of the spot by changing the focusing, over-focus, and under-focus states of the surface of the powder bed and the spot;

Step 5. Layered manufacturing: set the printing process parameters, the expected value of solar irradiance and the temperature limit of the powder bed, and the print head performs three-axis motion according to the set process parameters, so that the heat source moves on the surface of the single-layer plane powder bed, and then realizes the separation of the powder bed. Layer manufacturing process; after completing the manufacturing of one layer, the powder bed moves down to the corresponding layer height according to the program setting, repeats the feeding and leveling process, starts the next layer manufacturing, and then realizes the process of layer-by-layer stacking;

Step 6: Post-processing of additive manufacturing parts.

The beneficial effects of the present invention relative to the prior art are:

1. The powder bed cladding raw material interstellar soil accounts for 100%, which can realize the utilization of engineering materials completely in situ, which greatly reduces the transportation cost of in-situ construction materials for alien bases.

2. Directly focusing solar energy as the heat source for powder bed cladding, no energy conversion, direct energy utilization, simple and reliable system; energy deposition rate up to 80%, high energy utilization efficiency.

3. Compared with the traditional production method of building materials, it can realize the in-situ preparation of building materials products with various and flexible configurations.

4. Real-time regulation and related measures of environmental perception, strong environmental adaptability. The real-time control of the additive manufacturing process based on the perception of environmental variables can effectively reduce the impact of environmental changes on the powder bed cladding process. The invention has four degrees of freedom of movement for chasing light, can well adapt to time periods and regions with a low sun altitude angle, effectively improve the working window of the additive manufacturing device, and the available sun altitude angle can be as low as 20°.

抗压强度提升3～4倍，断裂韧性提升2～3倍。5. High-temperature selective melting powder bed cladding with large spot (millimeter level), low speed (0.1-10mm/s) and large penetration depth (above 5mm), so that the original powder undergoes solid (powder)-liquid (melt) cladding - The solid (block) phase transformation process turns the originally loose powder into a solid block, effectively improving the internal bonding force and density of the product. The powder bed cladding alien soil product has undergone a heat treatment process based on thermal properties to eliminate residual stress and phase transformation and toughening, and the mechanical properties are significantly improved. After heat treatment, the compressive strength of the simulated lunar soil product can reach 40Mpa, and the fracture toughness can reach

The compressive strength is increased by 3 to 4 times, and the fracture toughness is increased by 2 to 3 times.

Description of drawings

Figure 1 is a schematic diagram of a powder bed cladding additive manufacturing device;

2 is a schematic structural diagram of a converging lens type print head;

FIG. 3 is a schematic diagram of the structure of the optical fiber type print head;

Fig. 4 is the structure schematic diagram of powder spreader;

Fig. 5 is a schematic diagram of the structure of the chasing base;

Figure 6 is a functional relationship diagram of each component of the powder bed cladding additive manufacturing device;

Fig. 7 is the roadmap of powder bed cladding additive manufacturing method;

Figure 8 is a schematic diagram of the internal structure of the barrel;

Fig. 9 is a schematic diagram of self-correction chasing light path correction effect;

Figure 10 is an infrared measurement map of the simulated lunar soil temperature field for 10S-45S direct focused sunlight 3D printing at the beginning of printing;

Figure 11 shows the effect of the direct focused sunlight powder bed cladding 3D printing process;

Figure 12 is a schematic diagram of an example of simulated lunar soil direct focused solar powder bed cladding;

13 is a schematic structural diagram of a print head actuation system;

Figure 14 is a schematic diagram of X, Y axis tracking correction value calculation;

In the figure, 1, print head, 2, print head actuation system, 3, powder bed platform, 4, automatic light tracking system, 5, real-time control system, 11, cluster lens print head, 12, optical fiber print head , 13, the first guide column, 14, the second guide column, 21, the horizontal motor group, 22, the first guide rail, 23, the second guide rail, 24, the first transmission belt, 25, the second transmission belt, 31, the frame, 32, powder spreader, 33, barrel, 34, printing base plate, 35, telescopic rod, 36, vertical transmission device, 41, light tracking sensor, 42, light tracking base, 51, irradiance sensor, 52, infrared temperature sensor, 111, converging lens, 112, lens holder, 113, first print head base, 114, damping hinge, 121, optical fiber, 122, optical fiber head, 123, connecting rod, 124, connecting piece, 125, adjustment knob , 126, the second print head base, 211, the first motor, 212, the second motor, 331, the printing substrate, 332, the heater, 333, the first heat insulation layer, 334, the solid powder board, 335, the second spacer Heat Layer, 336, Gasket, 337, Positioning Piston, 338, Platen, 339, Powder, 321, Hopper, 322, Feeding Motor, 323, Driving Roller, 324, Driven Roller, 325, Linear Motion Mechanism, 361 , vertical motor, 362, vertical screw, 421, upper base plate, 422, lower base plate, 423, turret, 424, electric push rod, 425, rotary bearing, 426, rotating motor, 427, universal wheel, 429, Hinge, 3251, speed regulating reciprocating motor, 3252, horizontal screw, 3253, third rail, 3254, start limit switch, 3255, unloading limit switch, 3256, end limit switch, 3257, fixing frame, 3258 , slider.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings 1-14 and specific embodiments.

Specific implementation one

A powder bed cladding additive manufacturing device for interstellar base construction, including a print head 1, a print head actuation system 2, a powder bed platform 3 and an automatic light tracking system 4, as shown in FIG. 1, the print head 1 is subjected to The control of the print head actuation system 2 keeps the print head 1 located above the powder bed platform 3 and perpendicular to the upper surface of the powder bed platform 3, the interstellar soil is laid on the powder bed platform 3, and the automatic tracking system 4 sends sunlight The energy is concentrated on the print head 1.

Further, the powder bed platform 3 includes a rack 31 , a powder spreader 32 , a material barrel 33 and a printing base plate 34 , and the powder spreader 32 is located above the material barrel 33 and is slidably arranged on the rack 31 along the horizontal direction. , the barrel 33 is hinged with the frame 31 through several telescopic rods 35, the length of the telescopic rods 35 can be adjusted freely, and the two ends of each telescopic rod 35 are respectively connected with the top of the frame 31 and the material through universal joints. The side wall of the barrel 33 is hinged, so that the barrel 33 and the frame 31 are relatively fixed. By adjusting the length of the telescopic rod 35, the relative position and angle between the barrel 33 and the printing bottom plate 34 can be adjusted, which is convenient to adjust the surface of the powder bed and the coke. The relative position of the plane and the incident angle of the light source, the cartridge 33 is provided with a printing substrate 331, a heater 332, a first thermal insulation layer 333, a solid powder plate 334, a second thermal insulation layer 335, and a sealing gasket in order from top to bottom. 336 and the positioning piston 337, the sealing gasket 336 is sealingly connected with the inner wall of the barrel 33, the sealing gasket 336 is fixedly connected with the piston head of the positioning piston 337 through the pressure plate 338, and the bottom of the powder bed is sealed to prevent the powder from passing through the The gap between the positioning head and the material cylinder 33 slides down, and the piston rod of the positioning piston 337 is fixed on the printing base plate 34, and the printing base plate 34 is set on the frame 31 by sliding in the vertical direction through the two vertical transmission devices 36, so The vertical transmission device 36 is arranged on two opposite sides of the frame 31, and the vertical transmission device 36 includes a vertical motor 361 and a vertical screw 362, and one end of the vertical screw 362 passes through the top of the frame 31. Bearing connection, the other end is fixedly connected with the output shaft of the vertical motor 361, the vertical motor 361 is fixed on the bottom of the frame 31, and the printing bottom plate 34 is connected with the vertical screw 362 in a driving manner, so that the printing bottom plate 34 is in the vertical plane. Moving along the Z-axis direction, the extraterrestrial soil powder material is filled in the empty area inside the barrel 33 to form a powder bed.

Further, the solid powder plate 334 is a honeycomb structure, and the solid powder plate 334 is filled with the powder 339 to be processed, and a firm powder base layer is formed by the tightening action of the honeycomb, and then the friction force between the powder particles is achieved. Keep the overall structure of the powder bed stable and fix the positioning bolts. The functions of the first insulating layer 333 and the second insulating layer 335 are to isolate the heater 332 to ensure the insulation, reliability and service life of the components, and the materials are aluminum silicate fiberboard and silica aerogel felt. Or similar non-metal thermal insulation materials; the heater 332 is placed on the first thermal insulation layer 333 for auxiliary heating of the powder bed, and the relative position is relatively stable through the positioning bolts installed on the solid powder plate 334 . The heater 332 can be a metal (cast copper, cast iron) shell or a ceramic shell heating plate, the internal heating element is an iron-chromium-aluminum heating wire, or a stainless steel shell heating plate, and the internal heating element is a mica sheet. Preferably, the printing substrate 331 is a foamed ceramic substrate, which is placed on the heater 332, and its main function is to transfer heat to the powder bed manufacturing area as a thermal bridge heater, and to provide adhesion and prevent the powder bed cladding the first layer. The occurrence of defects such as warpage that may be caused by melting and condensation. The thickness of the powder on the foam ceramic substrate should match the parameters of the light spot and the thermal properties of the material, and the thickness of the powder 339 should be 4-10mm. The foam ceramic material is foamed alumina or foamed silicon carbide.

Further, the print head actuation system 2 includes a horizontal motor group 21 , a first guide rail 22 , a second guide rail 23 , a first transmission belt 24 and a second transmission belt 25 , and the horizontal motor group 21 includes a first motor 211 and a second transmission belt 25 . Two motors 212, the first motor 211 and the second motor 212 are both arranged on the upper surface of the frame 31, the print head 1 is slidably arranged on the first guide rail 22, and the first guide rail 22 is slidably arranged on the second On the guide rail 23, the second guide rail 23 is fixed on the frame, the first guide rail 22 and the second guide rail 23 are perpendicular to each other, and the print head 1 is provided with a first guide column 13 and a second guide column in the horizontal direction 14. The first transmission belt 24 is wound around the output shaft of the first motor 211, one end is connected to the first guide column 13, and the other end is connected to the second guide column 14; the second transmission belt 25 is wound around the output shaft of the second motor 212 and one end is connected to the first The guide column 13 is connected, and the other end is connected with the second guide column 14 . The free movement of the print head in the horizontal plane is controlled by adjusting the number of revolutions of the output shafts of the first motor 211 and the second motor 212, as shown in FIG. 13 .

Further, the powder spreader 32 includes a hopper 321, a feeding motor 322, a driving roller 323, a driven roller 324 and a linear motion mechanism 325. The linear motion mechanism 325 is fixed on the top frame of the frame 31, and the The hopper 321 is slidably arranged on the linear motion mechanism 325, the unloading motor 322 is fixed on the side wall of the hopper 321, the driving roller 323 and the driven roller 324 are rotatably installed at the bottom of the hopper 321, and the driving roller 323 is connected to the bottom of the hopper 321. The output shaft of the feeding motor 322 is connected by a pulley and a conveyor belt, the surface of the driving roller 323 is provided with a feeding trough that is parallel to the central axis of the driving roller 323, and the driven roller 324 has a smooth surface and is closely attached to the driving roller 323. In combination, the driven roller 324 has a smooth surface and is attached to the powder laid on the printing substrate 331, and is used to press the powder along with it. As shown in FIG. 4, the powder spreader 32 is mainly used for unloading. And the role of powder bed leveling. The linear motion mechanism 325 includes a speed-regulating reciprocating motor 3251, a transverse screw 3252, a third guide rail 3253, a starting limit switch 3254, a lowering limit switch 3255, an end limit switch 3256 and a fixing frame 3257. One end of the lever 3252 is connected with the fixing frame 3257 through a bearing, and the other end is connected with the output shaft of the speed-regulating reciprocating motor 3251. The speed-regulating reciprocating motor 3251 is fixed on the fixing frame 3257, and one side of the hopper 321 passes through the slider 3258 It is drivingly connected with the transverse screw 3252, and the other side is slidingly connected with the third guide rail 3253. The starting limit switch 3254, the unloading limit switch 3255, and the end limit switch 3256 are all arranged on the fixing frame 3257. The material limit switch 3255 is set between the start limit switch 3254 and the end limit switch 3256, and the speed regulating reciprocating motor 3251 drives the hopper 321 to reciprocate between the start limit switch 3254 and the end limit switch 3256. The main function of the linear motion mechanism 325 is to drive the hopper 321 to move to the unloading position and return to its original position to realize the leveling function. The functions of the three limit switches are to limit the movement range of the hopper 321 and the distance of unloading.

Further, the print head 1 is a clustered lens print head 11 or an optical fiber print head 12, and different types of print heads can be compatible and used through a unified installation interface. Degree of freedom; the energy fiber type print head can adjust the defocus amount.

Further, the convergent lens print head 11 includes a convergent lens 111, a lens holder 112, a first print head base 113 and a damping hinge 114, the convergent lens 111 is mounted on the lens holder 112, and the The damping hinge 114 connects the lens holder 112 and the first print head base 113, so that the converging lens 111 rotates around the damping hinge 114 on the vertical plane, so that the converging lens 111 has the degree of freedom to rotate in the vertical plane. A print head base 113 is fixed on the print head actuating system 2 , as shown in FIG. 2 .

Further, the automatic light tracking system 4 includes a light tracking sensor 41, a light tracking base 42 and a light tracking controller. The light tracking sensor 41 is arranged on the light collector, and its receiving surface is kept parallel to the receiving surface of the light collector. , the condenser provides heat for the print head 1. If the print head is a cluster lens print head 11, the condenser is a cluster lens, and the tracking sensor 41 follows the lens holder 112 around the damping hinge 114. Rotate to keep its receiving surface always parallel to the converging cluster lens 111 lens. The chasing base 42 includes an upper base plate 421, a lower base plate 422 and a turret 423. The powder bed platform 3 is disposed on the upper base plate 421, the lower base plate 422 is disposed below the upper base plate 421, and the upper base plate 421 One side edge of the upper bottom plate 422 and one side edge of the lower bottom plate 422 are rotatably connected, and an electric push rod 424 is provided between the other side edge of the upper bottom plate 421 and the other side edge of the lower bottom plate 422. The end of the cylinder body is installed on the upper surface of the lower base plate 422 through the rotating shaft, the rod end of the electric push rod 424 is connected to the lower surface of the upper base plate 421 through the rotating shaft, and the upper base plate 421 and the lower base plate 422 are controlled by the telescoping of the electric push rod 424 It rotates around the hinge 429, thereby driving the powder bed platform 3 to rotate in the vertical plane. The lower part of the lower bottom plate 422 is connected to the turret 423 through the rotating bearing 425, and the rotating bearing 425 is arranged on the output shaft of the rotating motor 426. , the rotating motor 426 is fixed on the turret 423, and several universal wheels 427 are installed on the bottom of the turret 423 to drive the chasing base 42 to automatically rotate in the horizontal plane. As shown in FIG. 5, the chasing light The sensor 41, the electric push rod 424 and the rotating motor 426 are electrically connected to the light tracking controller. The electric push rod 424 is used to track the sun altitude angle, and the rotating motor 426 is used to track the sun azimuth angle. Preferably, the light tracking control The device is an automatic light tracking dual-axis controller, which controls the actions of the electric push rod 424 and the rotating motor 426 of the light tracking base 42 according to the feedback of the light tracking sensor 41, so as to realize the rotation and pitch dual-DOF tracking. When the optical fiber-based print head 12 is used as a heat source for powder bed cladding, the automatic light tracking system 4 and the optical fiber-based print head 12 are installed independently.

Further, the optical fiber type print head 12 includes an optical fiber 121, an optical fiber head 122, a connecting rod 123, a connecting piece 124, an adjustment knob 125 and a second print head base 126. The optical fiber head 122 is connected to the optical fiber 121, and the optical fiber The head 122 is fixed on the bottom of the connecting rod 123, the connecting piece 124 is provided with a through hole, the top of the connecting rod 123 passes through the through hole, and the connecting rod 123 is fixed on the connecting piece 124 by the adjustment knob 125, the said The connecting piece 124 is fixed on the second print head base 126 , and the second print head base 126 is fixed on the print head actuating system 2 . The fiber-based print head 12 focuses the solar energy and projects a high-energy spot into the powder bed area by means of energy conversion or energy conduction through the fiber 121 to realize the powder bed cladding additive manufacturing process, and adjust the relative position of the fiber head 122 and the powder bed by adjusting the knob 125 , and then adjust the defocus amount of the fiber output end and the working plane of the energy fiber output end. As shown in Figure 3.

Further, the device also includes a real-time control system 5, the real-time control system 5 includes an irradiance sensor 51, an infrared temperature sensor 52 and a control system, the irradiance sensor 51 is fixed on the frame 31, and it receives The plane is kept parallel to the upper surface of the frame 31, the infrared temperature sensor 52 is fixed on the frame 31, and its lens is set facing the powder bed platform 3, the irradiance sensor 51, the infrared temperature sensor 52 and the print head are activated Both systems 2 are electrically connected to the control system. The control system receives the signals of the irradiance sensor 51 and the infrared temperature sensor 52 and the printing instructions including the process parameter information, and controls the equipment-related systems to realize real-time regulation of powder bed cladding additive manufacturing. The real-time control system judges the continuity of the printing process according to the feedback of the irradiance sensor 51 and the infrared temperature sensor 52 and the maximum temperature of the powder bed surface, and controls the printing process in real time.

The functional relationship of each part of a powder bed cladding additive manufacturing device for the construction of an interstellar base is shown in Figure 6.

Further, photovoltaic panels and solar cells are arranged on the light-following base 42 for normal operation of the device in an alien environment without infrastructure guarantee.

Further, in the way of directly focusing sunlight as a heat source for additive manufacturing, in addition to energy optical fibers and convergent lenses, other forms of high-energy point heat source print heads can be used as the powder bed of the technical solution of the present invention. A heat source for cladding additive manufacturing.

Further, the powder bed platform 3 can be replaced with different sizes of the powder bed platform 3 according to the size of the parts to be manufactured, so as to realize the addition of different scales from the test piece (millimeter level), the component (decimeter level) to the structure (meter level). Manufacturing, realize the organic combination of additive manufacturing part scale, raw material consumption and manufacturing efficiency.

Specific embodiment two

A method for in-situ use of solar energy to realize additive manufacturing of interstellar soil resource powder bed cladding, in-situ focusing solar energy as a thermal radiation type point heat source print head 1, driving the print head 1 to move in a plane, and selectively heating the interstellar soil-based powder bed, so that the It is completely melted at high temperature, then cooled and solidified, and powder is spread layer by layer, directly using solar energy to realize additive manufacturing of powder bed cladding of interstellar soil resources. Specifically include the following steps:

Step 1. Material pretreatment: Relatively uniform particle size distribution and suitable fluidity are of great significance to achieve good quality of powder bed cladding parts. In order to make the powder materials reach the ideal working state, the powder materials should be screened and gradation adjusted, and the following requirements should be met: 1) The powder materials should be sieved, and the aperture of the sieve used should not be greater than 100 meshes. 2), the powder angle of repose θ, when 20°≤θ≤40°;

Step 2, laying the powder bed and loading and leveling: according to the arrangement of the powder bed platform 3 recorded in the specific embodiment 1, lay the powder bed in turn from bottom to bottom, to achieve the following two purposes: 1), ensure that the powder bed is in the The overall stability of the solar powder bed cladding process; 2), preheating and auxiliary heating the powder bed to reduce the temperature gradient in the powder bed cladding process; The plate scrapes the surface of the powder along the outer edge of the barrel 33, so that the upper surface of the powder is flush with the outer edge of the barrel 33 of the powder bed platform 3 to form a powder bed; adjust the surface of the powder bed to the focal plane of the heat source;

Step 3: Preheating: Before printing starts, use the PID self-tuning temperature control device to control the heater 332 to preheat the powder bed. The set temperature of the heater 332 is 300°C-500°C, the preheating time is 10-20min, and the preheating target is that the surface temperature of the powder bed is not lower than 15%-20% of the melting temperature of the material, generally not lower than 200°C.

Step 4. Adjust the focusing state of the light spot: adjust the telescopic rod 35 to adjust the surface of the powder bed to a suitable relative position with the light spot, so as to adjust the energy level and Spot size. The diameter of the spot of the converging concentrator is not greater than 120% of the diameter of the spot in the focused state, and the defocus of the optical fiber concentrator is 10-15mm;

Step 5. Layered manufacturing: input the printing path, track spacing, printing speed, layer height and other process parameters, as well as the expected value of solar irradiance, powder bed temperature limit and other thresholds into the control system of the main control computer, and print head 1 according to the set process The parameters perform three-axis motion, so that the heat source moves on the surface of the single-layer plane powder bed, and then realizes the layered manufacturing process; after completing the manufacture of one layer, the powder bed moves down the corresponding layer height along the Z-axis according to the program setting, and repeats the upper and lower layers. The material leveling process starts, and the next layer of manufacturing is started, and then the process of layer-by-layer stacking is realized.

Step 6: Post-processing of additive manufacturing parts, heat treatment should be carried out after powder bed cladding additive manufacturing parts are manufactured. The specific steps are as follows:

Step 1. Perform differential scanning calorimetry DSC analysis, thermal expansion DIL analysis and viscosity temperature test on the additively manufactured parts;

Step 2. Determine the exothermic crystallization peak temperature point according to the DSC test result, determine the softening point according to the DIL test, and determine the temperature corresponding to the viscosity of 10 ¹² to 10 ¹³ Pa·s according to the viscosity temperature test as the annealing point;

Step 3. For the material without the DSC crystallization exothermic peak, the heat treatment process is as follows: first, the material is heated to the softening point for 1-2 hours, and then lowered to the annealing point for 1-2 hours; for the material with the DSC crystallization exothermic peak The heat treatment process is as follows: first, the material is heated to the softening point for 1-2 hours, then the temperature is increased or cooled to the crystallization peak temperature for 2-3 hours, and finally the temperature is lowered to the annealing point for 1-2 hours. After the heat treatment is completed, the surface of the additive manufacturing part is ground according to the quality requirements of the additive manufacturing part.

The solar powder bed cladding process parameter setting method includes the following steps:

(1) Establish a digital model of the target parts:

The design determines the shape and size of the additive manufacturing part, and on this basis, uses the CAD software to establish a 3D digital model of the additive manufacturing part, and outputs the following three 3D model file formats: STL, STEP, IGES.

(2) Planning the printing path for additive manufacturing:

On the premise that the material properties and the performance requirements of the parts are matched, the additive manufacturing printing path planning is carried out, and the key parameters of powder bed cladding are determined. The key parameters need to be determined as follows: filling style, path spacing, filling method, layer height, and printing speed.

The filling style is a path style in which the point heat source moves and fills to form a two-dimensional solid in a single layer, including unidirectional sweep filling, reciprocating sweep, honeycomb filling, cross square filling and coaxial spiral filling, etc.

The path spacing is the distance between two adjacent printing paths, which is set according to 45% to 55% of the diameter of the point heat source used. The filling method should choose one-time filling or partition filling according to the thermal processing characteristics of the material and environmental factors.

According to the high melting point silicate powder material and the characteristics of the point heat source, the thickness of a single layer is 1-5mm, and the printing speed is 0.1-10mm/s.

(3) The digital model slice generates G code:

Input the key parameters determined by the additive manufacturing path planning into the 3-D printing slicing software slic3r, and set the additive manufacturing start code, interlayer code and end code in the slicing software to generate the whole process of powder bed cladding G code. The G code commands that should be included in the start code are: unlocking the motor, setting the unit, setting absolute/relative coordinates, and returning to the zero point. The G code commands that should be included in the inter-layer code are: speed switching, layer withdrawal, queue waiting (pause, used for inter-layer feeding leveling). The end code should include: return to zero, lock the motor.

(4) Select the chasing mode:

The technical solution of the present invention can realize three different chasing modes of self-correction chasing, single-axis automatic chasing and dual-axis automatic chasing through the mutual cooperation of software and hardware systems, ensuring that the Fresnel lens is used to directly condense the powder bed. Manufacturing accuracy and stability for cladding additive manufacturing.

1. Self-correction chasing light

The self-correcting light tracking is suitable for the following situations: 1), mechanical conditions, environmental conditions or energy conditions are limited, which is not conducive to the normal operation of the automatic light tracking device; 2), the time period when the sun position changes relatively slowly; 3), powder The material has a small angle of repose, and the fluidity of the powder bed is excellent. The inclination in the vertical plane and the rotation in the horizontal plane will have a great impact on the overall stability of the powder bed.

The self-correcting chasing method is as follows: adjust the chasing base 42 to a suitable inclination angle, rotate the chasing base 42 and the angle of the converging lens concentrator so that the concentrator faces the sunlight, and adjust the relative position of the light spot by considering the change of the sun's azimuth. Influence, and then correct the powder bed cladding G code to achieve self-correction chasing light. In the self-correcting chasing mode, the time for one part manufacturing should not exceed 20 minutes. The chasing correction values Δx and Δy of the G code correction on the X and Y axes are determined by the following formulas, refer to Figure 14:

where Δx——the displacement of the light spot in the X direction per unit time (mm/min);

Δh _s — change of the sun’s altitude angle per unit time (°/min);

α——Platform inclination angle (°);

h _S1 , h _S2 ——the sun altitude angle (°) between the previous moment and the next moment;

R——lens focal length (mm);

m——the horizontal distance (mm) from the center of the lens to the hinge of the platform axis.

Δy= _RtanΔAs

where Δy——the spot displacement in the Y direction per unit time (mm/min);

R——lens focal length (mm);

ΔA _s ——The change of solar azimuth angle per unit time (°/min).

Then, the tracking correction value is time-averaged according to the process parameters, and the original G code path is subjected to tracking correction according to the time-averaged tracking correction value. The G code coordinate correction is calculated as follows:

In the formula, X', Y'——X, Y coordinate value of G code after correction (mm)

X ₀ , Y ₀ ——Original G code X, Y coordinate value (mm)

L _x , L _y ——The path increment in the X and Y directions between the two coordinate points of the G code (mm)

V——printing speed (mm/min)

Δx, Δy——Spot displacement in X and Y directions per unit time (mm/min)

2. Single-axis chasing light

The single-axis chasing light is suitable for the following situations: 1) The time period when the sun altitude angle changes relatively slowly; 2) The inclination in the vertical plane has a great influence on the overall stability of the powder bed, but the rotation in the horizontal plane has little effect on the overall stability of the powder bed .

The single-axis chasing method is: adjust the chasing base 42 to a suitable inclination angle, turn on the azimuth automatic chasing in the horizontal direction, and then correct the powder bed cladding G code by considering the influence of the change of the sun's altitude on the relative position of the light spot. Fix chasing. The correction value Δy of G code correction on the Y axis is determined according to the above formula.

3. Dual axis chasing light

The dual-axis chasing light is suitable for the following conditions: 1), the mechanical conditions, environmental conditions, and energy conditions are good, and can support the normal operation of the whole system; 2), the tilt in the vertical plane and the rotation in the horizontal plane have little effect on the overall stability of the powder bed; 3), the sun altitude angle is greater than 20 °.

The dual-axis tracking method is as follows: the sun orientation information is captured by the four-quadrant illuminance sensor and fed back to the tracking controller. The tracking controller uses the method of small step approximation to drive the related motors of the tracking base to rotate and lift to realize automatic tracking.

(5) Enter the G code into the device:

The G code can be sent to the host computer in the following three ways: USB cable connection, SD card or U disk and other storage device connection, TCP/IP connection.

(6) Layered manufacturing:

The main control computer drives the actuation system to realize the plane action of the XY axis and the vertical action of the Z axis according to the G code instructions, thereby realizing the process of layered manufacturing and layer-by-layer stacking.

(7) Real-time regulation of environmental perception:

By comparing the solar irradiance I measured by the irradiance sensor 51 with the expected value of the set irradiance, and comparing the peak temperature T of the powder bed measured by the infrared temperature sensor 52 with the set value T ₀ of the powder bed temperature. When I and T meet the requirements, the 3D printing process proceeds normally; otherwise, it is suspended until the environmental variables meet the requirements, thereby reducing the impact of environmental changes on the solar additive manufacturing process.

The selection of the expected value of solar irradiance I ₀ is calculated as follows:

I ₀ =Icos(α-h _s ) (4)

In the formula, I——the working irradiance (W·m ^-2 ) that the tracking light sensor can work normally;

α——Platform inclination angle (°);

h _s ——Sun altitude angle (°).

The selection of the maximum temperature setting value T ₀ of the powder bed is selected according to 0.9 times the melting temperature of the powder material.

Example 1

This embodiment provides an additive manufacturing device and method for directly focusing sunlight to realize powder bed cladding of high melting point silicate material. The principles of the powder bed cladding device and the additive manufacturing method and specific implementations of mutual cooperation will be further elaborated below.

A powder bed cladding additive manufacturing method for simulating lunar soil directly utilizing solar energy, the embodiment of which is:

1. Condenser selection: The condenser adopts a single-plane point-focusing Fresnel lens with a diameter of 310mm as the condenser component, the condenser power is 86.8W, and the spot diameter is 7mm. The Fresnel lens projects the concentrated high-energy solar beam onto the surface of the powder bed, interacts with the raw material, absorbs and scatters, and causes the surface temperature of the raw material to rise rapidly into a molten state in a short period of time, and then cool and consolidate, so that the powder can be absorbed and scattered. The purpose of forming the body material.

2. Condenser adjustment: In the condenser scheme of the plane converging lens, the damping hinge 114 can ensure that the lens is perpendicular to the sun when the sun altitude angle is low, and the powder bed will not reach or exceed due to the platform inclination angle. The angle of repose collapses, thereby effectively increasing the available solar altitude angle range and extending the working window. In this embodiment, under the condition that the change of the spot size is less than 15% and the attenuation of the energy flux density of the spot does not exceed 25%, the concentrator can be tilted by 30° through the damping hinge 114 .

3. Powder preheating: Ensuring proper printing accuracy is an important requirement for additive manufacturing. On the one hand, the overall stability of the powder bed needs to be maintained during the powder bed cladding process; on the other hand, the high melting point inorganic non-metallic materials have large temperature gradients and high cooling rates during the sintering process, and inorganic non-metallic materials generally have poor toughness, so it is necessary to predict The hot powder bed prevents the damage of the cladding parts caused by the direct focused sunlight powder bed due to excessive temperature gradient and cooling rate. In the embodiment of the simulated lunar soil, a silicone pad is used as the sealing pad 336, a stainless steel welded honeycomb plate is used as the solid powder plate 334, and an aluminum silicate fiber felt is used as the first thermal insulation layer 333 and the second thermal insulation layer 335, A cast copper heater was used as the heater 332 , and foamed alumina was used as the printing substrate 331 . The silicone pad is kept fixed with the upper surface of the piston head of the powder bed positioning piston 337 through the stainless steel pressure plate 338; the powder bed is kept stable as a whole by the solid powder plate 334, and the powder enters the solid powder plate 334 grid and is fully fastened by the honeycomb, forming a stable The base layer and the upper powder are firmly connected to the base layer powder through the friction between particles, which maximizes the stability of the powder bed during the additive manufacturing process; by burying the heater 332 in the powder bed to fully preheat the entire powder bed, Reduce the temperature gradient in the cladding process; the aluminum silicate fiber felt insulation layer effectively isolates the heat transfer between the heater 332, the solid powder plate 334 and the silicone gasket 336, protects the solid powder plate 334 and the silicone gasket 336 and reduces additional heat loss . On the one hand, the foamed alumina ceramic printing substrate 331 can improve the uneven heat transfer of the powder, so that the upper working area of the powder bed has a better preheating effect. On the other hand, it can provide adhesion for the first layer of the powder bed cladding process and relieve rapid cooling. problems such as warping. The laying effect of the powder bed is: the thickness of the powder is 11mm, the temperature of the heater 332 is 500°C, the side length of the honeycomb grid is 3mm, the preheating surface temperature of the powder bed reaches 170-230°C, and the temperature gradient in the molten pool area during the printing process is up to 177.64K/mm .

4. Blanking and leveling: In the embodiment of the simulated lunar soil powder bed directly cladding by sunlight, the powder spreader 32 realizes programmed automatic blanking and leveling through a programmable logic controller (PLC) control device. Automatic blanking includes blanking action and reciprocating action. The blanking action drives the driving roller 323 to rotate through the blanking motor 322, and the powder is transported into the powder bed platform 3 through the groove of the driving roller 323, and the depth of the groove of the driving roller 323 is 3.5-5mm; by adjusting the speed of the blanking motor 322 control Feed quantity. The driven roller 324 has rotational freedom but does not rotate synchronously with the driving roller 323, and is used to guide the feeding direction and level the powder bed. The reciprocating action drives the hopper 321 to reciprocate along the third guide rail 3253 through the speed-regulating reciprocating motor 3251 . The range of the reciprocating motion and the cutting position are controlled by the starting limit switch 3254 , the cutting limit switch 3255 , and the end limit switch 3256 . The starting limit switch 3254 and the ending limit switch 3256 control the reciprocating motion range of the hopper 321, and the relative positions of the unloading limit switch 3255 and the ending limit switch 3256 jointly determine the unloading section. The specific procedure of cutting is as follows: the hopper 321 starts from the starting limit switch 3254, and activates the cutting limit switch 3255 when it crosses the cutting limit switch 3255 for the first time; Turn, the hopper 321 returns, and at the same time the feeding motor 322 starts to rotate, and starts feeding; when the hopper 321 passes the feeding limit switch 3255 for the second time, the feeding motor 322 stops rotating and stops feeding; then, the hopper 321 returns to The starting point is limited, and the blanking program ends. The automatic feeding device feeds back the signal of the limit switch group to the PLC, and the controller controls the motion state of the feeding motor 322 and the speed-regulating reciprocating motor 3251 according to the predetermined sequence program to realize the programmed automatic feeding and leveling function. The rotation of the speed-regulating reciprocating motor 3251 of the device drives the hopper 321 to reciprocate at a speed of 100mm/s, and the blanking motor 322 blanks at a speed of 2r/s, which can realize a single powder-spreading and blanking amount of 200cm ³ .

5. Process parameter setting: in the implementation example of the simulated lunar soil, the process parameters are set according to the solar powder bed cladding process parameter setting method of the present invention, and the process parameters used are: scanning speed 0.5mm/s-5mm/s , the track length is 10-15mm, the track spacing is 2-4mm, the layer height is 3mm-5mm, the preheating temperature is 500°C, the surface temperature of the powder bed is 220°C; the solar irradiance is 1250W/m ² , and the effective melting temperature of the simulated lunar soil is 1150°C , the expected value I ₀ of solar irradiance is 900W/m ² , and the set value T ₀ of the powder bed temperature is 1100°C.

The setting basis and control process of the above-mentioned implementation and control parameters, the expected value of solar irradiance I ₀ and the set value of powder bed temperature T ₀ are as follows: Since the additive manufacturing process of silicate materials needs to ensure sufficient energy deposition to make the raw materials melt or sinter A significant challenge in additive manufacturing processes with sunlight as a heat source is the impact of environmental changes on the stability of the solar heat source. At the same time, a sufficient and stable light source is also a precondition for the automatic light-following system 4 to work normally. The stability of the concentrated solar heat source is directly related to the solar irradiance, and directly affects the maximum temperature of the powder bed surface during the powder bed cladding process. Therefore, in the technical solution of the present invention, the solar irradiance and the maximum temperature of the powder bed surface are selected as the judgment basis for environmental perception. The solar irradiance I degree is collected by the irradiance sensor 51 , and the maximum temperature T of the powder bed surface is collected by the non-contact infrared temperature sensor 52 . The collected data is compared with the set expected irradiance value I ₀ and the expected temperature value T _0. When I>I ₀ and T>T ₀ , the additive manufacturing process is carried out normally; when I < I ₀ or T < T ₀ , pause the additive manufacturing process until the maximum powder bed temperature and solar irradiance meet the requirements.

Optionally, the light chasing method in the embodiment may be automatic light tracking and self-correction light tracking. When self-correction light tracking is adopted, a specific example is as follows:

First, the sun azimuth is calculated to obtain the time series information of the sun altitude and azimuth angle of the location; secondly, the correction value of the printing path is calculated according to the calculation formula of the correction value of the X and Y directions in the technical solution of the present invention; thirdly, according to the model information and process parameter information Generate the original uncorrected G code; finally, combine the original G code, process parameter information and chasing correction value, average the chasing correction value according to the path size and printing speed, and time-average the correction value Add the corresponding coordinate point values in the original G code to obtain a self-correcting direct powder bed cladding printing instruction that considers the change of the sun's azimuth and does not require mechanical tracking. The schematic diagram of the path correction effect is shown in Figure 9. The process parameter information used in this path correction example is: printing speed V=0.5mm/s, X-direction path increment _Lx =17.5mm, Y-direction path increment _Ly =6mm, and the path correction information is shown in the table below.

Table 1 Path correction information

6. Three-dimensional forming: In the embodiment of the simulated lunar soil, the print head actuating system 2 drives the concentrator print head to move in the XY plane according to the predetermined path including the process parameters according to the G code instruction; The body and the frame 31 are connected by the telescopic rod 35, the bottom surface of the material cylinder 33 and the cylinder body can slide relative to each other, and are connected with the positioning piston 337 that can move up and down under the driving of the printing bottom plate 34, forming a piston-like mechanism, and then on the printing bottom plate 34 The Z-axis movement is realized under the driving of the powder bed, and the process of layer-by-layer superposition is realized by driving the powder bed to move up and down. The heating effect of the heater 332 on the raw material powder bed is coordinated to realize the process of layered manufacturing.

7. Post-processing: In the simulated lunar soil example, the DSC test results show that there is an exothermic crystallization peak at 800-1100 ° C, the DIL test results show that the powder bed cladding sample has a softening point temperature of 900-1000 ° C, and the viscosity temperature test results Indicates that the material annealing point is 590-620°C. Accordingly, the post-processing process of the simulated lunar soil is as follows: heating at 10-15°C/min to 1000-1100°C for 2 hours, and then cooling to 600°C at a rate of 5-10°C/min for 2 hours to eliminate temperature stress, Finally, the parts are subjected to surface treatment such as grinding and polishing according to the requirements.

The way of heat treatment may include, but is not limited to, heat treatment by means of direct focusing sunlight spot and speckle heating, reflective and converging heating, and resistance heating furnace. The glass phase products are first printed, and then the purposeful crystallization is transformed into ceramic phase products through heat treatment. The main effect is that the phase changes qualitatively, and the strength and toughness are significantly improved, making the raw materials from unusable to usable. At the same time, it can also have The flexibility of 3D printing. Additive manufacturing parts after heat treatment have good processability, and can be processed by grinding, mechanical polishing, etc., or without surface treatment under the conditions of use with low surface requirements.

In the example of the simulated lunar soil powder bed cladding, the measured temperature field of the powder bed cladding is shown in Figure 10, the example of the powder bed cladding sample is shown in Figure 11, and the measured data of the compressive strength of the simulated lunar soil powder bed cladding samples are shown in Figure 10. As shown in table 2.

Table 2 Measured compressive strength of simulated lunar soil powder bed cladding samples

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims (11)

1. A powder bed cladding additive manufacturing device for interstellar base construction, characterized in that it comprises a print head (1), a print head actuation system (2), a powder bed platform (3) and an automatic light tracking system (4) ), the print head (1) is controlled by the print head actuation system (2) to keep the print head (1) above the powder bed platform (3) and perpendicular to the upper surface of the powder bed platform (3). The powder bed platform (3) is laid on the powder bed platform (3), the automatic light tracking system (4) concentrates the energy of sunlight on the print head (1), and the powder bed platform (3) includes a frame (31), a powder coating device (32), material cylinder (33), printing base plate (34) and several telescopic rods (35), the powder spreader (32) is located above the material cylinder (33) and is slidably arranged on the rack in the horizontal direction (31), the cartridge (33) is hinged to the frame (31) through a plurality of telescopic rods (35), and the cartridge (33) is provided with a printing substrate (331), a heating plate (331), heating The device (332), the first heat insulation layer (333), the solid powder board (334), the second heat insulation layer (335), the sealing gasket (336) and the positioning piston (337), the sealing gasket (336) and the The inner side wall of the material cylinder (33) is sealedly connected, the gasket (336) is fixedly connected with the piston head of the positioning piston (337), and the piston rod of the positioning piston (337) is fixed on the printing base plate (34), so The printing base plate (34) is slidably arranged on the frame (31) along the vertical direction. 2. The powder bed cladding additive manufacturing device for interstellar base construction according to claim 1, characterized in that: the powder spreader (32) comprises a hopper (321), a feeding motor (322), a driving roller ( 323), a driven roller (324) and a linear motion mechanism (325), the linear motion mechanism (325) is fixed on the top frame of the frame (31), and the hopper (321) is slidably arranged on the linear motion mechanism (323). 325), the unloading motor (322) is fixed on the side wall of the hopper (321), the driving roller (323) and the driven roller (324) are rotatably installed at the bottom of the hopper (321), the driving The roller (323) is connected with the output shaft of the feeding motor (322) through a conveyor belt, the surface of the driving roller (323) is provided with a feeding groove, and the driven roller (324) has a smooth surface and is connected with the driving roller (323) For bonding, the driven roller (324) is bonded with the powder laid on the printing substrate (331). 3. The powder bed cladding additive manufacturing device for interstellar base construction according to claim 1, wherein the print head (1) is a convergent lens print head (11) or an optical fiber print head (12). ). 4. The powder bed cladding additive manufacturing device for interstellar base construction according to claim 3, characterized in that: the convergent lens print head (11) comprises a convergent lens (111), a lens holder (112) ), a first print head base (113) and a damping hinge (114), the converging lens (111) is mounted on the lens holder (112), the damping hinge (114) connects the lens holder (112) and the first A print head base (113) makes the converging lens (111) rotate around the damping hinge (114) on the vertical plane, and the first print head base (113) is fixed on the print head actuating system (2). 5. The powder bed cladding additive manufacturing device for interstellar base construction according to claim 3, characterized in that: the optical fiber print head (12) comprises an optical fiber (121), an optical fiber head (122), a connecting rod ( 123), a connecting piece (124), an adjustment knob (125) and a second print head base (126), the optical fiber head (122) is connected to the optical fiber (121), and the optical fiber head (122) is fixed on the connecting rod ( 123), the connecting piece (124) is provided with a through hole, the top end of the connecting rod (123) passes through the through hole, and the connecting rod (123) is fixed on the connecting piece (124) through the adjusting knob (125). ), the connecting piece (124) is fixed on the second print head base (126), and the second print head base (126) is fixed on the print head actuating system (2). 6. The powder bed cladding additive manufacturing device for interstellar base construction according to claim 1, characterized in that: the automatic light tracking system (4) comprises a light tracking sensor (41), a light tracking base (42) and Light tracking controller, the receiving surface of the light tracking sensor (41) is kept parallel to the receiving surface of the light collector, the light collector provides heat for the print head (1), and the light tracking base (42) includes an upper bottom plate (421), a lower base plate (422) and a turret (423), the powder bed platform (3) is arranged on the upper base plate (421), and the lower base plate (422) is arranged below the upper base plate (421), One side edge of the upper bottom plate (421) and one side edge of the lower bottom plate (422) are rotatably connected, and the other side edge of the upper bottom plate (421) and the other side edge of the lower bottom plate (422) are arranged between There is an electric push rod (424), and the lower part of the lower bottom plate (422) is connected with the turret (423) through a rotary bearing (425), and the rotary bearing (425) is arranged on the output shaft of the rotary motor (426), The rotating motor (426) is fixed on the turret (423), and a number of universal wheels (427) are installed on the bottom of the turret (423), the light tracking sensor (41), the electric push rod (424) ) and the rotating motor (426) are both electrically connected to the light tracking controller. 7. The powder bed cladding additive manufacturing device for interstellar base construction according to claim 1, characterized in that: the device further comprises a real-time control system (5), and the real-time control system (5) includes irradiance A sensor (51), an infrared temperature sensor (52) and a control system, the irradiance sensor (51) is fixed on the frame (31), its receiving plane is kept parallel to the upper surface of the frame (31), the infrared The temperature sensor (52) is fixed on the frame (31), the lens of which is arranged facing the powder bed platform (3), the irradiance sensor (51), the infrared temperature sensor (52) and the print head actuating system (2) ) are electrically connected to the control system. 8. A method for realizing interstellar soil resource powder bed cladding additive manufacturing by in-situ utilization of solar energy using the device according to any one of claims 1-7, wherein the in-situ focused solar energy is used as a thermal radiation type point heat source The print head (1) drives the plane movement of the print head (1), selectively heats the interstellar soil-based powder bed, makes it completely melted at high temperature, then cools and solidifies, and spreads powder layer by layer, directly using solar energy to realize the cladding of the interstellar soil resource powder bed Additive Manufacturing. 9. method according to claim 8, is characterized in that: specifically comprises the following steps: Step 1. Material pretreatment: sieve the powder material; Step 2: Loading and leveling: add the pretreated powder material into the powder bed platform (3), scrape the powder surface to form a powder bed, and adjust the surface of the powder bed to the focal plane of the heat source; Step 3. Preheating: Preheating the powder bed platform (3) to a surface temperature of not lower than 15%-20% of the melting temperature of the material; Step 4. Adjust the focus state of the spot: adjust the surface of the powder bed to a suitable relative position with the spot, so as to adjust the energy level and spot size of the spot by changing the focusing, over-focus, and under-focus states of the surface of the powder bed and the spot; Step 5. Layered manufacturing: set printing process parameters, expected value of solar irradiance and powder bed temperature limit, the print head (1) performs three-axis motion according to the set process parameters, so that the heat source moves on the surface of the single-layer plane powder bed, And then realize the layered manufacturing process; after completing the manufacturing of one layer, the powder bed moves down the corresponding layer height according to the program setting, repeats the feeding and leveling process, starts the next layer of manufacturing, and then realizes the layer-by-layer stacking process; Step 6: Post-processing of additive manufacturing parts. 10. The method according to claim 9, wherein: in step 5, the specific steps of setting the process parameters are as follows: S1, establishing a digital model of the target part: designing and determining the shape and size of the additively manufactured part, and based on this Using CAD software to build a 3D digital model of additive manufacturing parts; S2. Planning the additive manufacturing printing path: on the premise that the material characteristics and the performance requirements of the parts match, carry out the additive manufacturing printing path planning, and determine the key parameters of powder bed cladding; S3. Digital model slicing to generate G code: Input the key parameters determined by the additive manufacturing path planning into the 3-D printing slicing software, and set the additive manufacturing start code, interlayer code and end code in the slicing software to generate powder G code for the whole process of material powder bed cladding; S4. Selecting a chasing mode, the chasing mode includes self-correcting chasing, single-axis chasing and dual-axis chasing; S5. Input the G code into the main control computer; S6. Hierarchical manufacturing: The main control computer drives the print head actuation system (2) and the powder bed platform (3) according to the G code instructions to realize the XY axis plane actuation and the Z axis vertical actuation, thereby realizing layered manufacturing and one by one. The process of layer stacking; S7. Real-time regulation of environmental perception: by comparing the solar irradiance I measured by the irradiance sensor (51) parallel to the upper surface of the powder bed platform (3) with the set irradiance expected value, The peak temperature T of the powder bed measured by the infrared temperature sensor (52) on the upper surface of the platform (3) is compared with the set value T ₀ of the powder bed temperature. When I and T meet the requirements, the 3D printing process is carried out normally; otherwise, the 3D printing process is suspended until Environmental variables meet the requirements, thereby mitigating the impact of environmental changes on the solar AM process. 11. The method according to claim 9, characterized in that: in step 6, the specific steps of the post-processing of the additively manufactured parts are as follows: Step 1. Perform differential scanning calorimetry DSC analysis, thermal expansion DIL analysis and viscosity temperature test on the additively manufactured parts; Step 2. Determine the exothermic crystallization peak temperature point according to the DSC test result, determine the softening point according to the DIL test, and determine the temperature corresponding to the viscosity of 10 ¹² ~ 10 ¹³ Pa·s according to the viscosity temperature test as the annealing point; Step 3. For the material without the DSC crystallization exothermic peak, the post-treatment process is as follows: first, the material is heated to the softening point and kept for 1-2 h, and then lowered to the annealing point for 1-2 h; The post-processing process is as follows: firstly, the material is heated to the softening point and kept for 1-2 h, then the temperature is raised or lowered to the crystallization peak temperature for 2-3 h, and finally the temperature is lowered to the annealing point for 1-2 h. h.

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