Cooling device and cooling method for powder bed electron beam 3D printing equipment

Abstract

The invention relates to a cooling device and a cooling method for powder bed electron beam 3D printing equipment. The cooling device comprises an argon charging port, an argon discharging port and a cooling device, an air cooling structure; the water cooling structure is arranged on the outer side face of a bottom plate of the forming chamber; cooling the copper block; a temperature measuring device; and the cooling gas conveying device, the cooling liquid conveying device and the temperature measuring device are respectively connected with the upper computer. Argon can be introduced into the forming chamber through the argon inflation inlet, the air cooling structure is arranged on the inner wall of the forming cylinder, and even if gas leaks into the forming cylinder, printing of parts in the forming cylinder cannot be damaged; the water cooling structure is arranged outside the forming cylinder, water cannot enter the forming cylinder even if water leaks, and the safety of the part printing process is guaranteed; the temperature measuring device is adopted for monitoring the temperature in the forming cylinder in real time, the upper computer can control cooling gas and cooling liquid according to the temperature of the part, and the forming quality of the part is guaranteed.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of additive manufacturing technology, and in particular to a cooling device and a cooling method for a powder bed electron beam 3D printing device. Background Art

[0002] Rapid prototyping technology is a technology that uses powder as raw material to form parts through selective deposition / sintering / melting processes. It is a hot topic in the field of rapid manufacturing. Typical technologies include: Selective Laser Sintering (SLS), Selective Laser Melting (SLM), Electron Beam Melting (EBM), and Three Dimensional Printing (3DP). The process flow of these technologies is similar: first, a layer of raw material powder is spread on the processing plane, and then the processing source partitions the powder according to the cross-sectional shape of the part to form the cross-sectional contour of the part. After a layer of powder is formed, the powder spreading device spreads another layer of powder on the forming work surface, and the processing source performs a selective operation on the layer of powder again, and completes the connection between the newly generated layer and the original part. This cycle is repeated layer by layer, and finally, after post-processing, a solid part of any shape is obtained.

[0003] The selective sintering technology completes the processing of parts through layered scanning. During the processing, after each layer is processed, the lifting table drops a certain distance, the powder feeder sends out a certain amount of powder, and the powder spreading mechanism spreads it, and then the layer of powder is sintered. The process of sintering-table lowering-powder feeding-powder spreading is repeated continuously to complete the processing. Since the printing process is equivalent to the process of sintering parts, even after printing, the working area still has a high temperature and needs to be cooled to room temperature before the print can be taken out, but the printing environment is a high vacuum environment and the cooling speed is slow. Depending on the size of the formed part, the longest cooling time can be more than 48 hours, which seriously affects the printing efficiency.

[0004] After the powder bed electron beam 3D printing equipment is completed, the active cooling system is used to accelerate the cooling of the formed parts, mainly including air cooling and water cooling, in order to shorten the cooling time and thus improve the overall printing efficiency. However, due to the small specific heat capacity of gas, the cooling effect of air cooling is limited; the structural design of water cooling is relatively complex, and the water channel must be safe and reliable to prevent water from leaking into the forming chamber. In a high temperature environment, water leakage will oxidize the powder and parts in the forming chamber, so the reliability and stability are low.

[0005] During the cooling process, on the one hand, due to the above limitations of air cooling and water cooling, the cooling effect is not good; on the other hand, if you blindly pursue rapid cooling, it is easy to produce large thermal stress, causing deformation or cracking of parts, and adversely affecting the internal quality of parts. Therefore, how to reasonably and effectively cool the powder bed electron beam 3D printing equipment is a technical problem that needs to be solved in this field.

[0006] Therefore, it is necessary to improve one or more problems existing in the above-mentioned related technical solutions.

[0007] It should be noted that this section is intended to provide background or context for the technical solutions of the present invention stated in the claims. The description herein is not admitted to be prior art by inclusion in this section. Summary of the invention

[0008] The object of the present invention is to provide a cooling device and a cooling method for a powder bed electron beam 3D printing device, thereby at least to a certain extent solving one or more problems caused by the limitations and defects of the related art.

[0009] The present invention first provides a cooling device for a powder bed electron beam 3D printing device, the 3D printing device comprising: a forming chamber and a lifting system optical axis, the forming chamber is provided with a forming cylinder, the forming cylinder is provided with a lifting workbench, the lifting system optical axis is arranged below the lifting workbench, the lifting system optical axis passes through the bottom plate of the forming chamber and is fixedly connected to the lifting workbench, the cooling device comprises: An argon gas filling port, which is arranged on the inner wall of the forming chamber and is located below the lifting workbench; An air cooling structure, the air cooling structure is arranged on the inner wall of the forming cylinder, and the air cooling structure is connected to a cooling gas conveying device; A water cooling structure, the water cooling structure is arranged on the outer side of the bottom plate of the forming chamber, and the water cooling structure is connected to the cooling liquid conveying device; A cooling copper block, wherein the cooling copper block is detachably arranged at the upper end of the optical axis of the lifting system, and the upper end of the optical axis of the lifting system is located in the forming chamber; A temperature measuring device, which is arranged on the lower surface of the lifting workbench and is used to monitor the temperature in the forming cylinder in real time; The host computer, the cooling gas delivery device, the cooling liquid delivery device and the temperature measuring device are respectively connected to the host computer.

[0010] In the present invention, an air inlet duct and an air outlet duct connected to the air cooling structure are provided in the forming chamber, and the air inlet duct is connected to the cooling gas conveying device.

[0011] In the present invention, a liquid channel is provided inside the optical axis of the lifting system, and the water cooling structure and the coolant delivery device are respectively connected to the liquid channel.

[0012] In the present invention, the liquid inlet and the liquid outlet of the liquid channel are both arranged at the lower end of the optical axis of the lifting system, and the lower end of the optical axis of the lifting system is arranged outside the forming chamber.

[0013] In the present invention, the longitudinal section of the cooling copper block is T-shaped; the partial structure of the T-shaped structure is a tubular structure, and the tubular structure is sleeved on the optical axis of the lifting system.

[0014] In the present invention, the cooling device also includes a circulation device for extracting the gas in the forming cylinder and the air-cooling structure or the liquid in the water-cooling structure and the liquid channel.

[0015] The present invention secondly provides a method for cooling a powder bed electron beam 3D printing device, wherein the above-mentioned cooling device is used to cool the powder bed electron beam 3D printing device, and the cooling method comprises: Before printing the parts, the liquid in the liquid channel inside the optical axis of the lifting system and the gas in the forming cylinder are extracted by using a circulation device; After printing is completed, argon gas in a first temperature range is charged into the forming chamber through the argon gas charging port, cooling gas is charged into the air cooling structure by the cooling gas delivery device, cooling liquid is delivered to the water cooling structure by the cooling liquid delivery device, and the cooling copper block is installed on the optical axis of the lifting system; The temperature in the forming cylinder is monitored in real time by using the temperature measuring device, and the monitored temperature value is sent to the host computer; The host computer adjusts the flow rate and temperature of the cooling gas and coolant according to the received temperature value; After the parts are cooled, the argon gas in the forming cylinder is extracted using a circulation device.

[0016] In the present invention, the temperature of the coolant delivered to the water cooling structure decreases as the temperature of the component decreases.

[0017] In the present invention, the first temperature range is: 15~25°C.

[0018] In the present invention, the step of adjusting the flow rate and temperature of the cooling gas and the cooling liquid according to the received temperature value by the host computer comprises: When the monitored temperature value decreases by 100°C, the temperature of the cooling gas decreases by 3~6°C and the temperature of the coolant decreases by 3~6°C.

[0019] The technical solution provided by the present invention includes the following beneficial effects: In the present invention, argon gas can be introduced into the forming chamber by using the argon gas filling port to cool the printed parts; an air cooling structure is arranged on the inner wall of the forming cylinder, and even if the gas leaks into the forming cylinder, it will not cause damage to the printed parts in the forming cylinder; a water cooling structure is arranged outside the forming chamber, and even if water leaks, it will not enter the inside of the forming chamber, thereby ensuring the safety of the part printing process; a temperature measuring device is used to monitor the temperature inside the forming cylinder in real time, and the temperature of the printed parts can be known in real time. The upper computer can control the flow rate and temperature of the cooling gas and coolant according to the temperature of the parts, so as to avoid the introduction of too low temperature cooling medium when the temperature of the parts is high, which affects the forming quality of the parts; the use of argon gas, air cooling structure, water cooling structure and cooling copper block can achieve the purpose of effectively and quickly cooling the parts, thereby improving the part printing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The accompanying drawings herein are incorporated into the specification and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the specification are used to explain the principles of the present disclosure. Obviously, the accompanying drawings described below are only some embodiments of the present disclosure, and for ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without creative work.

[0021] Figure 1 A schematic diagram showing the structure of a cooling device for a powder bed electron beam 3D printing device in an exemplary embodiment of the present invention; Figure 2 A schematic diagram showing the structure of a liquid channel in an exemplary embodiment of the present invention; Figure 3 A schematic structural diagram showing an air cooling structure in an exemplary embodiment of the present invention; Figure 4 A schematic structural diagram of a cooling copper block in an exemplary embodiment of the present invention is shown.

[0022] Reference numerals: 10. Forming chamber; 20. Lifting system optical axis; 21. Liquid channel; 211. Liquid inlet; 212. Liquid outlet; 30. Forming cylinder; 40. Lifting workbench; 100. Argon gas filling port; 200. Air cooling structure; 201. Air inlet pipe; 202. Air outlet pipe; 300. Water cooling structure; 400. Cooling copper block; 500. Temperature measuring device. DETAILED DESCRIPTION

[0023] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that the present invention will be more comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0024] In addition, the accompanying drawings are only schematic illustrations of embodiments of the present invention and are not necessarily drawn to scale. The same reference numerals in the drawings represent the same or similar parts, and their repeated descriptions will be omitted. Some of the block diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0025] In this example implementation, a cooling device for a powder bed electron beam 3D printing device is first provided. Figure 1 As shown, the 3D printing device includes: a forming chamber 10 and a lifting system optical axis 20. A forming cylinder 30 is provided in the forming chamber 10, and a lifting workbench 40 is provided in the forming cylinder 30. The lifting system optical axis 20 is arranged below the lifting workbench 40, and the lifting system optical axis 20 passes through the bottom plate of the forming chamber 10 and is fixedly connected to the lifting workbench 40.

[0026] The temperature reduction device comprises: an argon gas filling port 100, an air cooling structure 200, a water cooling structure 300, a cooling copper block 400, a temperature measuring device 500 and a host computer.

[0027] Specifically, the argon gas filling port 100 is arranged on the inner wall of the forming chamber 10, such as on the bottom plate or the side wall, and is located below the lifting workbench 40. The air cooling structure 200 is arranged on the inner wall of the forming cylinder 30, for example, the air cooling structure 200 can be arranged on the four inner walls of the forming cylinder 30. The air cooling structure 200 is connected to the cooling gas delivery device, and the flow rate of the cooling gas is controlled by the cooling gas delivery device. The water cooling structure 300 is arranged on the outer side of the bottom plate of the forming chamber 10, and the water cooling structure 300 is connected to the coolant delivery device, and the flow rate of the coolant is controlled by the coolant delivery device. The cooling copper block 400 is arranged at the upper end of the lifting system optical axis 20, and the upper end of the lifting system optical axis 20 is located in the forming chamber 10. The temperature measuring device 500 is arranged on the lower surface of the lifting workbench 40, and is used to monitor the temperature in the forming cylinder 30 in real time.

[0028] The cooling gas delivery device, the cooling liquid delivery device and the temperature measuring device 500 are respectively connected to the host computer.

[0029] In this embodiment, argon gas can be introduced into the forming chamber 10 through the argon filling port 100 to cool the printed parts; an air cooling structure 200 is set on the inner wall of the forming cylinder 30, even if the gas leaks into the forming cylinder 30, it will not cause damage to the printed parts in the forming cylinder 30; the water cooling structure 300 is set outside the forming cylinder 30, even if water leaks, it will not enter the inside of the forming cylinder 30, ensuring the safety of the part printing process; the temperature inside the forming cylinder 30 is monitored in real time by a temperature measuring device 500, and the temperature of the printed parts can be known in real time. The upper computer can control and adjust the flow rate of the cooling gas and the coolant according to the temperature of the part, so as to avoid the introduction of too low a temperature cooling medium when the temperature of the part is high, which affects the forming quality of the part; the use of argon gas, the air cooling structure 200, the water cooling structure 300 and the cooling copper block 400 can effectively and quickly cool the parts, thereby improving the part printing efficiency.

[0030] It can be understood that, based on the above embodiment, the forming chamber 10 is provided with an air inlet pipe 201 and an air outlet pipe 202 connected to the air cooling structure 200, and the air inlet pipe 201 is connected to the cooling gas delivery device. When the air inlet pipe 201 and the air outlet pipe 202 are set, they need to be well sealed to ensure that the gas in the pipe does not leak as much as possible. The cooling gas delivery device can be used to control the supply speed or supply temperature of the cooling gas.

[0031] For the water cooling structure 300, such as Figure 2 As shown, a liquid channel 21 is provided inside the lifting system optical axis 20, and the liquid channel 21 is connected to the water cooling structure 300. A coolant delivery device is used to deliver coolant to the liquid channel 21, and then the coolant flows into the water cooling structure 300 to cool the forming chamber 10. The coolant delivery device can control the delivery speed and temperature of the coolant.

[0032] like Figure 2 As shown, the liquid inlet 211 and the liquid outlet 212 of the liquid channel 21 are both arranged at the lower end of the lifting system optical axis 20, and the lower end of the lifting system optical axis 20 is arranged outside the forming chamber 10, so that the liquid inlet 211 and the liquid outlet 212 are both arranged outside the forming chamber 10, which can prevent the liquid from being exposed in the forming chamber 10 after leakage, and ensure that the liquid will not affect the parts in the forming chamber 10.

[0033] In order to further speed up the cooling rate of the parts in the forming chamber 10, a detachable cooling copper block 400 is provided on the lifting system optical axis 20, which is used to transfer the heat of the lifting table 40 to the lifting system optical axis 20. The temperature of the parts in the forming chamber 10 is first transferred to the lifting table 40, and then the lifting table 40 transfers the heat to the cooling copper block 400, and then the cooling copper block 400 transfers the heat to the lifting system optical axis 20. The lifting system optical axis 20 is provided with a liquid channel 21 inside, and the coolant therein is used to absorb the heat.

[0034] For further information, please refer to Figure 4 The longitudinal section of the cooling copper block 400 can be set to be T-shaped; the T-shaped part is a tubular structure, and the tubular structure is sleeved on the lifting system optical axis 20. The contact area between the cooling copper block 400 and the lifting workbench 40 and the lifting system optical axis 20 is large, and heat can be transferred quickly.

[0035] In the above embodiment, a circulation device can also be used to extract the gas in the forming cylinder 30 and the air cooling structure 200, the liquid in the water cooling structure 300 and the liquid channel 21. After extraction, the water cooling structure 300 and the air cooling structure 200 are in a vacuum state, which reduces the heat transfer medium, so that the heat preservation effect of the printing area in the forming chamber 10 is better.

[0036] The present invention also provides a method for cooling a powder bed electron beam 3D printing device, wherein the cooling device described in the above embodiment is used to cool the powder bed electron beam 3D printing device, and the cooling method comprises: S101, before printing the part, the circulation device is used to extract the liquid in the liquid channel 21 inside the lifting system optical axis 20 and the gas in the forming cylinder 30. After the liquid and gas are extracted, the water cooling structure 300 and the air cooling structure 200 are in a vacuum environment.

[0037] S102, after printing is completed, argon gas in the first temperature range is filled into the forming chamber 10 through the argon filling port 100, cooling gas is filled into the air cooling structure 200 using the cooling gas delivery device, cooling liquid is delivered to the water cooling structure 300 using the cooling liquid delivery device, and the cooling copper block 400 is installed on the optical axis 20 of the lifting system.

[0038] S103, using the temperature measuring device 500 to monitor the temperature in the forming cylinder 30 in real time, and sending the monitored temperature value to the host computer.

[0039] S104, the host computer adjusts the flow rate and temperature of the cooling gas and the cooling liquid according to the received temperature value.

[0040] S105, after the parts are cooled, the argon gas in the forming cylinder 30 is extracted using a circulation device.

[0041] In this embodiment, before the part is printed, the water cooling structure 300 and the air cooling structure 200 are both in a vacuum state, which can effectively keep the printing area warm; after printing, argon gas in the first temperature range is filled into the forming chamber 10, cooling gas is filled into the air cooling structure 200, coolant is delivered to the water cooling structure 300, and the cooling copper block 400 is installed to initially cool the part. The temperature is measured in real time using the temperature measuring device 500, and the upper computer analyzes the temperature value, and controls the temperature and rate of the above cooling components according to the temperature adjustment of the part, so that the part will not be subjected to sudden cooling, etc., to ensure that the forming quality of the part is not affected.

[0042] Among them, the argon gas filled into the forming chamber 10 will not react with the powder used for part printing, and will not affect the forming of the parts. Since the density of argon gas is greater than that of air, it will gather at the bottom of the forming chamber 10, so that the heat of the parts can be fully absorbed. When the heat is absorbed to a certain extent, it will be extracted by the circulation device to exchange the heat out of the forming chamber 10. At the same time, the heat of the argon gas will also be exchanged through the water cooling structure 300, so as to achieve the purpose of cooling the parts. The filling and extraction of argon gas is carried out in a cycle.

[0043] Typically, the first temperature range is 15-25° C., but is not limited thereto and can be appropriately adjusted according to the performance characteristics of the component.

[0044] During the parts cooling process, the host computer adjusts the coolant and cooling gas temperatures according to the received temperature values. The rule is: when the monitored temperature value decreases by 100°C, the cooling gas temperature decreases by 3~6°C, and the coolant temperature decreases by 3~6°C.

[0045] Specifically, the temperature measuring device 500 is generally a temperature sensor. During the cooling process of the part, when the actual temperature measured by the sensor is ≥600°C, the host computer automatically adjusts the temperature of the cooling gas to 25°C, the filling pressure to 0.12Mpa, and the filling flow rate to 1.5×10 4 PaL / s; the temperature of the cooling water is 20℃; When the sensor measured temperature is between 500℃ and 600℃, the host computer automatically adjusts the temperature of the cooling gas to 20℃, the charging pressure to 0.12Mpa, and the charging flow rate to 1.5×10 4 PaL / s; the temperature of the cooling water is 15℃; When the sensor measured temperature is between 400℃ and 500℃, the host computer automatically adjusts the temperature of the cooling gas to 15℃, the charging pressure to 0.1Mpa, and the charging flow rate to 2.0×10 4 PaL / s; the temperature of the cooling water is 10°C. For details, please refer to Table 1 to control the temperature and flow rate.

[0046] Table 1 Measured temperature and adjusted control temperature In order to ensure that the internal quality of the parts will not be adversely affected by rapid cooling, when the parts are at high temperature, the temperature of the cooling water and cooling gas filled in is relatively high. As the temperature of the parts decreases, the system will gradually reduce the temperature of the cooling water and cooling gas. When the part is in a high temperature state, the inflation pressure is increased, and argon gas under higher pressure is filled into the forming chamber 10 through the argon inflation port 100, so that the argon gas can directly blow the lifting workbench 40 to achieve a rapid cooling effect; as the temperature of the part decreases, the system will automatically increase the inflation flow rate and reduce the inflation pressure at the same time to ensure the balance of the vacuum degree.

[0047] In the above embodiments, the cooling gas in the air cooling structure 200 can also be circulated according to the heat exchange conditions; the water cooling structure 300 is a water cooling block.

[0048] It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like that may appear in the above description indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the embodiments of the present invention.

[0049] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the embodiments of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0050] In the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, or a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0051] In the embodiments of the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0052] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example" or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification.

[0053] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses or adaptations of the present invention, which follow the general principles of the present invention and include common knowledge or customary techniques in the art that are not disclosed by the present invention. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present invention are indicated by the appended claims.

Claims

1. A cooling device for a powder bed electron beam 3D printing device, the 3D printing device comprising: A forming chamber and a lifting system optical axis, wherein a forming cylinder is provided in the forming chamber, a lifting workbench is provided in the forming cylinder, the lifting system optical axis is arranged below the lifting workbench, and the lifting system optical axis passes through the bottom plate of the forming chamber and is fixedly connected to the lifting workbench, characterized in that the cooling device comprises: An argon gas filling port, which is arranged on the inner wall of the forming chamber and is located below the lifting workbench; An air cooling structure, the air cooling structure is arranged on the inner wall of the forming cylinder, and the air cooling structure is connected to a cooling gas conveying device; A water cooling structure, the water cooling structure is arranged on the outer side of the bottom plate of the forming chamber, and the water cooling structure is connected to the cooling liquid conveying device; A cooling copper block, wherein the cooling copper block is detachably arranged at the upper end of the optical axis of the lifting system, and the upper end of the optical axis of the lifting system is located in the forming chamber; A temperature measuring device, which is arranged on the lower surface of the lifting workbench and is used to monitor the temperature in the forming cylinder in real time; The host computer, the cooling gas delivery device, the cooling liquid delivery device and the temperature measuring device are respectively connected to the host computer.

2. The cooling device for powder bed electron beam 3D printing equipment according to claim 1, characterized in that: An air inlet duct and an air outlet duct connected to the air cooling structure are arranged in the forming chamber, and the air inlet duct is connected to the cooling gas conveying device.

3. The cooling device for powder bed electron beam 3D printing equipment according to claim 1, characterized in that: A liquid channel is provided inside the optical axis of the lifting system, and the water cooling structure and the coolant delivery device are respectively connected to the liquid channel.

4. The cooling device for powder bed electron beam 3D printing equipment according to claim 3, characterized in that: The liquid inlet and the liquid outlet of the liquid channel are both arranged at the lower end of the optical axis of the lifting system, and the lower end of the optical axis of the lifting system is arranged outside the forming chamber.

5. The cooling device for powder bed electron beam 3D printing equipment according to claim 1, characterized in that: The longitudinal section of the cooling copper block is T-shaped; the partial structure of the T-shape is a tubular structure, and the tubular structure is sleeved on the optical axis of the lifting system.

6. The cooling device for powder bed electron beam 3D printing equipment according to claim 4, characterized in that: The cooling device also includes a circulation device for extracting the gas in the forming cylinder and the air-cooling structure or the liquid in the water-cooling structure and the liquid channel.

7. A method for cooling a powder bed electron beam 3D printing device, characterized in that: The cooling device according to claim 6 is used to cool the powder bed electron beam 3D printing equipment, and the cooling method includes: Before printing the parts, the liquid in the liquid channel inside the optical axis of the lifting system and the gas in the forming cylinder are extracted by using a circulation device; After printing is completed, argon gas in a first temperature range is charged into the forming chamber through the argon gas charging port, cooling gas is charged into the air cooling structure by the cooling gas delivery device, cooling liquid is delivered to the water cooling structure by the cooling liquid delivery device, and the cooling copper block is installed on the optical axis of the lifting system; The temperature in the forming cylinder is monitored in real time by using the temperature measuring device, and the monitored temperature value is sent to the host computer; The host computer adjusts the flow rate and temperature of the cooling gas and coolant according to the received temperature value; After the parts are cooled, the argon gas in the forming cylinder is extracted using a circulation device.

8. The cooling method of the powder bed electron beam 3D printing device according to claim 7, characterized in that: The temperature of the coolant delivered to the water cooling structure decreases as the temperature of the parts decreases.

9. The method for cooling a powder bed electron beam 3D printing device according to claim 8, characterized in that: The first temperature range is: 15~25℃.

10. The method for cooling a powder bed electron beam 3D printing device according to claim 9, characterized in that: The step of the host computer adjusting the flow rate and temperature of the cooling gas and the cooling liquid according to the received temperature value includes: When the monitored temperature value decreases by 100°C, the temperature of the cooling gas decreases by 3~6°C and the temperature of the coolant decreases by 3~6°C.

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