Electron beam additive manufacturing device and method

Abstract

The present invention belongs to the technical field of additive manufacturing, and discloses an electron beam additive manufacturing device and method. An electron beam additive manufacturing device includes a vacuum chamber, an electron gun, a powder spreading and feeding mechanism, and a heat insulation mechanism. A powder bed is arranged in the vacuum chamber; the output end of the electron gun and the powder spreading and feeding mechanism are both arranged in the vacuum chamber; the heat insulation mechanism includes a heat insulation component and a drive component. The heat insulation component includes a heat insulation screen arranged in the vacuum chamber, and the heat insulation screen is arranged around the powder bed. The drive component includes a drive member arranged outside the vacuum chamber, and the drive member is connected to the heat insulation screen, and is used to drive the heat insulation screen to move in a direction close to or away from the powder bed. In this way, the drive member is arranged outside the vacuum chamber, which can avoid the drive member being affected by the vacuum environment, reduce the motion interference with the powder spreading and feeding mechanism and the electron gun, maintain a good heat preservation effect, and reduce the failure rate of the drive member.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and in particular to an electron beam additive manufacturing device and method. Background Art

[0002] Additive manufacturing technology is a technology that manufactures solid parts by adding materials layer by layer based on three-dimensional data. Electron beam additive manufacturing, as one of the commonly used additive manufacturing methods, uses an electron beam to selectively melt metal powder particles in the processing area on the powder bed, thereby realizing the manufacture of metal three-dimensional entities.

[0003] When using an electron beam additive manufacturing device for additive manufacturing, the powder bed is in a vacuum environment. The electron beam scans the surface of the powder bed to make the surface of the powder bed reach a high temperature state, and then electron beam sintering is performed on the coordinate points of the powder bed corresponding to the control system. In order to achieve efficient and energy-saving printing, a heat insulation cover is required to keep warm and avoid heat loss.

[0004] In order to prevent the heat insulation cover from interfering with other structures during the powder spreading process, a driving member connected to the heat insulation cover is usually provided in the vacuum chamber, and the driving member can drive the heat insulation cover to move in the vacuum chamber. However, the internal structure of the driving member is relatively complex, which may affect the precise fit of the driving member in a vacuum environment and cause the driving member to fail, resulting in an increased failure rate of the driving member, affecting the normal movement of the heat insulation cover, and even interfering with the powder spreading and scraping mechanism. Summary of the invention

[0005] The object of the present invention is to provide an electron beam additive manufacturing device and method to solve the problem of high failure rate of a driving component for driving a heat shield to move.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In a first aspect, an electron beam additive manufacturing device comprises: a vacuum chamber, wherein a powder bed is arranged in the vacuum chamber; an electron gun and a powder spreading and feeding mechanism, wherein an output end of the electron gun and the powder spreading and feeding mechanism are both arranged in the vacuum chamber; a heat insulation mechanism, wherein the heat insulation mechanism comprises a heat insulation component and a drive component, wherein the heat insulation component comprises a heat insulation screen arranged in the vacuum chamber, wherein the heat insulation screen is arranged around the powder bed, and wherein the drive component comprises a drive member arranged outside the vacuum chamber, wherein the drive member is connected to the heat insulation screen and is used to drive the heat insulation screen to move in a direction close to or away from the powder bed.

[0008] Preferably, the electron beam additive manufacturing device further comprises a detection component, the detection component comprising a rising into position detection sensor arranged outside the vacuum chamber, the rising into position detection sensor being connected to the driving member and being used to detect whether the heat insulation shield has risen into position; and / or, the detection component comprises a descending into position detection sensor arranged outside the vacuum chamber, the descending into position detection sensor being connected to the driving member and being used to detect whether the heat insulation shield has descended into position.

[0009] Preferably, two driving members are provided, and the two driving members are symmetrically arranged on both sides of the heat insulation screen.

[0010] Preferably, the vacuum chamber is connected to a vacuum pump, and the heat insulation screen arranged toward the vacuum pump is provided with an exhaust hole.

[0011] Preferably, the heat insulation screen is provided with multiple layers, and the multiple layers of heat insulation screen located on the same side of the powder bed are stacked in sequence.

[0012] Preferably, the vacuum chamber is connected to a vacuum pump, and exhaust holes are provided on the multiple layers of heat insulation screens arranged toward the vacuum pump, and the exhaust holes on adjacent heat insulation screens are staggered.

[0013] Preferably, the heat insulation assembly further comprises a heat insulation frame, the heat insulation screen is arranged on the heat insulation frame and moves synchronously with the heat insulation frame, and the driving member is connected to the heat insulation frame.

[0014] Preferably, the driving assembly further comprises a sealing tube, one end of which is connected to the driving member, and the other end of which is connected to the insulation frame, for separating the interior of the sealing tube from the interior of the vacuum chamber.

[0015] Preferably, the heat insulation screen is provided with an observation hole.

[0016] In a second aspect, an electron beam additive manufacturing method is applied to the electron beam additive manufacturing device as described above, and the electron beam additive manufacturing method comprises the following steps: preparing powder spreading, the powder spreading and feeding mechanism conveys metal powder to the powder bed, the driving member drives the heat insulation screen to move away from the powder bed, so that the heat insulation screen rises and performs a powder scraping action; the driving member drives the heat insulation screen to move toward the powder bed, so that the heat insulation screen descends and covers the processing area; preheating the print so that the electron beam output by the electron gun sinters the metal powder; repeating the above steps until printing is completed.

[0017] Beneficial effects of the present invention:

[0018] An electron beam additive manufacturing device comprises a vacuum chamber, an electron gun, a powder spreading and feeding mechanism and a heat insulation mechanism, wherein a powder bed is arranged in the vacuum chamber; the output end of the electron gun and the powder spreading and feeding mechanism are both arranged in the vacuum chamber; the heat insulation mechanism comprises a heat insulation component and a drive component, the heat insulation component comprises a heat insulation screen arranged in the vacuum chamber, the heat insulation screen is arranged around the powder bed, the drive component comprises a drive member arranged outside the vacuum chamber, the drive member is connected to the heat insulation screen, and is used to drive the heat insulation screen to move in a direction close to or away from the powder bed.

[0019] In this way, since the driving component is arranged outside the vacuum chamber, the driving component can be prevented from being affected by the vacuum environment in the vacuum chamber, thereby reducing the failure rate of the driving component. In addition, the driving component drives the heat insulation screen to move in the vertical direction, which not only saves the moving space required for the heat insulation screen in the horizontal direction, but also facilitates the control of the rise and fall of the heat insulation screen, thereby avoiding the movement interference of the driving component and the heat insulation screen with the powder feeding mechanism and the electron gun during the movement. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of an electron beam additive manufacturing device in one embodiment of the present invention;

[0021] Figure 2 is a schematic diagram of a partial structure of an electron beam additive manufacturing device in one embodiment of the present invention;

[0022] Figure 3 is a schematic diagram of a partial structure of a vacuum pump in one embodiment of the present invention;

[0023] Figure 4 is a schematic diagram of the structure of a heat insulation board for showing exhaust holes in one embodiment of the present invention;

[0024] Figure 5 It is a schematic flow chart of an electron beam additive manufacturing method in one embodiment of the present invention.

[0025] In the figure:

[0026] 1. Vacuum chamber; 11. Vacuum pump; 2. Heat insulation mechanism; 21. Heat insulation assembly; 211. Heat insulation screen; 2111. Exhaust hole; 2112. Hook; 212. Heat insulation frame; 213. Mounting plate; 22. Drive assembly; 221. Drive member; 2211. Fixing plate; 222. Connecting rod; 23. Detection assembly; 231. Rise-in-place detection sensor; 232. Lower-in-place detection sensor. DETAILED DESCRIPTION

[0027] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0028] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or 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.

[0029] In 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.

[0030] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0031] See also Figure 1 The present invention provides an electron beam additive manufacturing device, comprising a vacuum chamber 1, an electron gun (not shown in the figure), a powder spreading and feeding mechanism (not shown in the figure) and a heat insulation mechanism 2, wherein a powder bed (not shown in the figure) is arranged in the vacuum chamber 1; the output end of the electron gun and the powder spreading and feeding mechanism are both arranged in the vacuum chamber 1; the heat insulation mechanism 2 comprises a heat insulation component 21 and a driving component 22, the heat insulation component 21 comprises a heat insulation screen 211 arranged in the vacuum chamber 1, the heat insulation screen 211 is arranged around the powder bed, the driving component 22 comprises a driving member 221 arranged outside the vacuum chamber 1, the driving member 221 is connected to the heat insulation screen 211, and is used to drive the heat insulation screen 211 to move in a direction close to or away from the powder bed.

[0032] In this embodiment, the powder bed is fixedly arranged inside the vacuum chamber 1, and five groups of heat insulation screens 211 are provided. The five groups of heat insulation screens 211 are respectively arranged around the powder bed and above the powder bed. The driving member 221 is a cylinder, and the fixed end of the cylinder is arranged outside the vacuum chamber 1. The fixed end of the cylinder is fixedly connected with a fixed plate 2211, and the fixed plate 2211 is flange-connected to the vacuum chamber 1. A sealing gasket (not shown in the figure) is also connected between the fixed plate 2211 and the vacuum chamber 1 to ensure the sealing performance inside the vacuum chamber 1. The output end of the cylinder is connected to the heat insulation screen 211 to move the heat insulation screen 211 in the vertical direction.

[0033] In this way, the driving member 221 is arranged outside the vacuum chamber 1, which can prevent the driving member 221 from being affected by the vacuum environment and reduce the failure rate of the driving member 221; the driving member 221 drives the heat insulation screen 211 to move in the vertical direction, which can save the moving space required for the heat insulation screen 211 in the horizontal direction, and facilitate rapid ascent and descent, reduce the movement interference with the powder feeding mechanism and the electron gun, and maintain a good thermal insulation effect.

[0034] It is understandable that the driving member 221 can also be a linear driving mechanism such as an electric push rod, a linear motor, etc., and is not limited to a cylinder. The type of the driving member 221 can be flexibly adjusted as long as it can drive the heat insulation screen 211 to move in a vertical direction. No more examples are given here.

[0035] See also Figure 1 and Figure 2 In some embodiments, the electron beam additive manufacturing device further includes a detection component 23, the detection component 23 includes a rising into position detection sensor 231 arranged on the outside of the vacuum chamber 1, the rising into position detection sensor 231 is connected to the driving member 221, and is used to detect whether the heat insulation shield 211 rises into position; the detection component 23 includes a descending into position detection sensor 232 arranged on the outside of the vacuum chamber 1, the descending into position detection sensor 232 is connected to the driving member 221, and is used to detect whether the heat insulation shield 211 descends into position.

[0036] Among them, an induction magnetic ring is arranged at the output end of the cylinder, and the rising position detection sensor 231 and the descending position detection sensor 232 are both magnetic switches. The rising position detection sensor 231 and the descending position detection sensor 232 are both fixedly arranged at the fixed end of the cylinder, and the rising position detection sensor 231 is arranged on the side of the descending position detection sensor 232 away from the vacuum chamber 1.

[0037] In this way, by setting the rising into position detection sensor 231 and the falling into position detection sensor 232, it is possible to determine whether the heat insulation screen 211 has risen or fallen into position by detecting the position state of the output end of the cylinder, so that the heat insulation screen 211 can insulate the powder bed more accurately or reserve space above the powder bed so that the powder spreading and feeding mechanism can carry out the powder spreading work, thereby avoiding interference between the driving component 221 and structures such as the electron gun and the powder spreading and feeding mechanism.

[0038] It can be understood that the rising position detection sensor 231 and the falling position detection sensor 232 can also be set as proximity switches or travel switches, which can detect the moving position of the output end of the cylinder; the driving member 221 can also detect the position state of the driving member 221 through an absolute value servo motor encoder, and then detect the position of the heat insulation screen 211. Using an absolute value servo motor encoder to detect the position is a prior art and will not be elaborated here.

[0039] See also Figure 1 In some embodiments, two driving members 221 are provided, and the two driving members 221 are symmetrically arranged on both sides of the heat insulation shield 211 .

[0040] In this embodiment, the driving members 221 are symmetrically arranged on both sides of the powder bed, and the driving members 221 are arranged on both sides of the heat insulation screen 211 located above the powder bed.

[0041] Furthermore, the area of ​​the heat insulation screen 211 located above the powder bed is smaller than that of the powder bed, the heat insulation screen 211 located above the powder bed is provided with a hole for the electron gun to extend into (not shown in the figure), and the heat insulation screens 211 located around the powder bed extend outwardly at one end close to the powder bed (that is, extend in a direction away from the powder bed), so that each heat insulation screen 211 encloses a trapezoidal space to accommodate the powder bed.

[0042] In this way, the symmetrically arranged driving member 221 can subject the heat insulation screen 211 to symmetrical forces, making the rise and fall of the heat insulation screen 211 more stable, and enabling the heat insulation screen 211 to move at a uniform speed, thereby reducing interference with the powder feeding mechanism and reducing the failure rate of the driving member 221.

[0043] It is understandable that the number and location of the driving members 221 can be flexibly adjusted according to actual needs as long as the driving members 221 are prevented from being affected by the vacuum environment, and no further details are given here.

[0044] See also Figure 3 and Figure 4 In some embodiments, the vacuum chamber 1 is connected to a vacuum pump 11, and a heat shield 211 disposed toward the vacuum pump 11 is provided with an exhaust hole 2111. The vacuum pump 11 is disposed at one side of the vacuum chamber 1, and the vacuum pump 11 is communicated with the inside of the vacuum chamber 1.

[0045] In this way, the residual gas generated by the powder bed during the processing can be sucked away by the vacuum pump 11 through the exhaust hole 2111, thereby improving the air permeability of the heat insulation shield 211 and the exhaust efficiency of the vacuum pump 11.

[0046] It is understandable that the setting position of the vacuum pump 11 can be flexibly adjusted according to actual needs, and the exhaust hole 2111 can also be set on the heat insulation screen 211 set away from the vacuum pump 11, so that the inside of the heat insulation screen 211 can be connected with the inside of the vacuum chamber 1, and no more examples are given here.

[0047] See also Figure 1 In some embodiments, the heat insulation screen 211 is provided with multiple layers, and the multiple layers of heat insulation screens 211 located on the same side of the powder bed are stacked in sequence. In this embodiment, the heat insulation screen 211 located on the same side of the powder bed is provided with three layers, that is, three layers of heat insulation screens 211 are provided around and above the powder bed, and the relative positions of the three layers of heat insulation screens 211 located on the same side of the powder bed are fixed, and the interval distance between adjacent heat insulation screens 211 ranges from 5 to 15 mm.

[0048] Furthermore, the heat shield 211 located in the innermost layer (i.e., the heat shield 211 closest to the powder bed) is made of high-temperature resistant non-magnetic stainless steel foil material and has the largest surface roughness to achieve the effect of protection and heat preservation. After the heat shield 211 closest to the powder bed contacts the metal vapor, due to its large surface roughness, it can improve the surface bonding force between the metal coating and the heat shield 211, thereby preventing the metal coating from falling off and affecting the additive manufacturing effect; the heat shield 211 located in the middle layer is made of mirror plate stainless steel material, which provides good thermal radiation reflection and reduces heat loss; the heat shield 211 located in the outermost layer (i.e., the heat shield 211 farthest from the powder bed) is made of the same material as the innermost heat shield 211, so that it can be used alternately with the innermost heat shield 211 to reduce the use cost of the electron beam additive manufacturing device.

[0049] In this way, by setting up a multi-layer heat insulation screen 211, the heat insulation effect of the heat insulation screen 211 can be improved to avoid heat loss, and under the action of the driving component 221, the heat insulation screen 211 can rise or fall quickly, so that the heat insulation screen 211 can be promptly lowered to cover the powder bed when insulation is needed. The operation is simple, and the driving component 221 can be prevented from malfunctioning due to the vacuum environment, thereby extending the service life of the electron beam additive manufacturing device.

[0050] It is understandable that the number of layers of the heat insulation screen 211 can also be adjusted according to actual needs and is not limited to three layers.

[0051] See also Figure 3 and Figure 4Furthermore, exhaust holes 2111 are provided on the multi-layer heat insulation screens 211 arranged toward the vacuum pump 11, and the exhaust holes 2111 on adjacent heat insulation screens 211 are staggered, that is, the exhaust holes 2111 on adjacent heat insulation screens 211 arranged toward the vacuum pump 11 do not overlap in their projections in a direction perpendicular to the heat insulation screens 211.

[0052] In this way, the exhaust holes 2111 on the heat insulation shield 211 are staggered, which can improve the thermal insulation performance while allowing the residual gas inside the heat insulation shield 211 to be discharged to the outside of the vacuum chamber 1 through the exhaust holes 2111 .

[0053] It is understandable that the exhaust holes 2111 on adjacent heat insulation screens 211 may also be arranged at the same position of each heat insulation screen 211 , and the arrangement position and number of the exhaust holes 2111 may be flexibly adjusted, which will not be elaborated herein.

[0054] See also Figure 1 In some embodiments, the thermal insulation assembly 21 further includes a thermal insulation frame 212 , the thermal insulation screen 211 is disposed on the thermal insulation frame 212 and moves synchronously with the thermal insulation frame 212 , and the driving member 221 is connected to the thermal insulation frame 212 .

[0055] In this embodiment, the insulation frame 212 is connected to a hook 2112, and the insulation screen 211 is set on the insulation frame 212 through the hook 2112. The insulation component 21 also includes a mounting plate 213, and the mounting plate 213 is fixedly connected to the insulation frame 212. The driving component 22 also includes a connecting rod 222, and the connecting rod 222 is connected to the output end of the driving member 221. The connecting rod 222 is detachably connected to the mounting plate 213 through bolts to realize the driving of the insulation screen 211.

[0056] In this way, the heat insulation screen 211 is driven to rise or fall by the connecting rod 222, the mounting plate 213, and the heat insulation frame 212, so that the movement stability of the heat insulation screen 211 can be improved, the movement interference with the powder feeding mechanism and the electron gun can be reduced, and the failure rate of the driving component 221 in the process of driving the heat insulation screen 211 to rise or fall can be reduced.

[0057] It can be understood that the mounting plate 213 can also be detachably connected to the insulation frame 212 by bolts, and the connecting rod 222 can also be fixedly connected to the mounting plate 213. The connection method between the mounting plate 213 and the insulation frame 212 and the connecting rod 222 can be flexibly adjusted according to actual needs. In this embodiment, the mounting plate 213 and the connecting rod 222 are detachably connected to facilitate the connection between the insulation screen 211 and the driving member 221.

[0058] See also Figure 1In some embodiments, the driving assembly 22 further includes a sealing tube (not shown in the figure), one end of which is connected to the driving member 221, and the other end is connected to the heat insulation frame 212, for separating the inside of the sealing tube from the inside of the vacuum chamber 1. In this embodiment, the sealing tube is a metal bellows, and the two ends of the metal bellows are respectively fixedly connected to the side of the connecting rod 222 facing the cylinder and the side of the cylinder fixed end facing the connecting rod 222 by welding, so that the inside of the metal bellows is in a non-vacuum state and the inside of the metal bellows is isolated from the inside of the vacuum chamber 1.

[0059] It should be noted that the output end of the cylinder drives the mounting plate 213, the insulation frame 212 and the insulation screen 211 to rise or fall synchronously, and the sealing tube expands and contracts following the movement of the output end of the cylinder, so that the insulation screen 211 rises when the powder spreading mechanism is spreading powder, and the insulation screen 211 falls during printing and preheating, so that the distance between the lower surface of the insulation screen 211 arranged around the powder bed and the molding surface of the powder bed can be controlled to 2-5mm, so as to improve the thermal insulation of the insulation screen 211.

[0060] In this way, the sealing tube can protect the output end of the cylinder from being affected by the vacuum environment, isolate the vacuum from the atmosphere, realize telescopic dynamic sealing, and can reduce the operating resistance of the cylinder, reduce the failure rate of the driving member 221, and enable the heat insulation shield 211 to rise or fall stably.

[0061] It is understandable that the sealing tube can also be other retractable structures, such as a sealing rubber tube, a sealing plastic tube, etc. In this embodiment, the sealing tube is a metal bellows in order to improve the structural strength of the sealing tube to achieve protection for the output end of the cylinder. The material of the sealing tube can be adjusted according to actual needs, which will not be elaborated here.

[0062] See also Figure 1 In some embodiments, the heat shield 211 is provided with an observation hole (not shown in the figure). In this embodiment, the observation hole is a grid hole, and the observation hole is arranged on the heat shield 211 away from the vacuum pump 11, so that the staff can observe the additive manufacturing situation inside the heat shield 211.

[0063] In this way, the observation hole can not only facilitate observation of the internal situation, but also enable the interior of the heat insulation shield 211 to communicate with the interior of the vacuum chamber 1 for easy exhaust.

[0064] It is understandable that the location and shape of the observation hole can be flexibly adjusted.

[0065] See also Figure 5 The present invention also provides an electron beam additive manufacturing method, which is applied to an electron beam additive manufacturing device. The electron beam additive manufacturing method comprises the following steps:

[0066] S1, prepare to spread powder, the powder spreading and feeding mechanism conveys metal powder to the powder bed, the driving member 221 drives the heat insulation screen 211 to move away from the powder bed, so that the heat insulation screen 211 rises and performs a powder scraping action;

[0067] S2, the driving member 221 drives the heat shield 211 to move towards the powder bed, so that the heat shield 211 descends and covers the processing area;

[0068] S3, preheating printing, so that the electron beam output by the electron gun sintering the metal powder;

[0069] S4. Repeat the above steps until printing is completed.

[0070] In step S1, the driving member 221 drives the heat insulation screen 211 to rise, and the sealing tube is compressed. When the rising into position detection sensor 231 detects that the heat insulation screen 211 has risen into position, the heat insulation screen 211 stops moving; the powder spreading mechanism includes a scraper, and the scraper performs a powder scraping action.

[0071] In step S2, the driving member 221 drives the heat shield 211 to descend in reverse, and the sealing tube is stretched. When the descending-in-place detection sensor 232 detects that the heat shield 211 has descended into place, the heat shield 211 stops moving;

[0072] In step S3, the staff can observe the additive manufacturing status of the powder bed processing area through the observation hole;

[0073] In step S4, after printing is completed, starting the vacuum pump 11 can discharge the residual gas inside the heat insulation shield 211 to the outside, and the driving member 221 can drive the heat insulation shield 211 to rise again, making it easier for the staff to take out the additive manufacturing product.

[0074] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An electron beam additive manufacturing device, characterized in that: include: A vacuum chamber (1), wherein a powder bed is arranged in the vacuum chamber (1); An electron gun and a powder spreading and feeding mechanism, wherein the output end of the electron gun and the powder spreading and feeding mechanism are both arranged in the vacuum chamber (1); A heat insulation mechanism (2), the heat insulation mechanism (2) comprising a heat insulation component (21) and a drive component (22), the heat insulation component (21) comprising a heat insulation screen (211) arranged in the vacuum chamber (1), the heat insulation screen (211) being arranged around the powder bed, the drive component (22) comprising a drive member (221) arranged outside the vacuum chamber (1), the drive member (221) being connected to the heat insulation screen (211) and being used to drive the heat insulation screen (211) to move in a direction close to or away from the powder bed.

2. The electron beam additive manufacturing device according to claim 1, characterized in that: The electron beam additive manufacturing device further comprises a detection component (23), wherein the detection component (23) comprises a rising-in-place detection sensor (231) arranged outside the vacuum chamber (1), wherein the rising-in-place detection sensor (231) is connected to the driving member (221) and is used to detect whether the heat insulation shield (211) has risen into place; and / or the detection component (23) comprises a falling-in-place detection sensor (232) arranged outside the vacuum chamber (1), wherein the falling-in-place detection sensor (232) is connected to the driving member (221) and is used to detect whether the heat insulation shield (211) has fallen into place.

3. The electron beam additive manufacturing device according to claim 1, characterized in that: Two driving members (221) are provided, and the two driving members (221) are symmetrically arranged on both sides of the heat insulation screen (211).

4. The electron beam additive manufacturing device according to claim 1, characterized in that: The vacuum chamber (1) is connected to a vacuum pump (11), and the heat insulation screen (211) arranged toward the vacuum pump (11) is provided with an exhaust hole (2111).

5. The electron beam additive manufacturing device according to claim 1, characterized in that: The heat insulation screen (211) is provided with multiple layers, and the multiple layers of the heat insulation screen (211) located on the same side of the powder bed are stacked in sequence.

6. The electron beam additive manufacturing device according to claim 5, characterized in that: The vacuum chamber (1) is connected to a vacuum pump (11), and exhaust holes (2111) are provided on the multiple layers of heat insulation screens (211) arranged toward the vacuum pump (11), and the exhaust holes (2111) on adjacent heat insulation screens (211) are staggered.

7. The electron beam additive manufacturing device according to any one of claims 1 to 6, characterized in that: The heat insulation component (21) further comprises a heat insulation frame (212), the heat insulation screen (211) is arranged on the heat insulation frame (212) and moves synchronously with the heat insulation frame (212), and the driving member (221) is connected to the heat insulation frame (212).

8. The electron beam additive manufacturing device according to claim 7, characterized in that: The driving assembly (22) further comprises a sealing tube, one end of which is connected to the driving member (221), and the other end of which is connected to the heat insulation frame (212), and is used to separate the interior of the sealing tube from the interior of the vacuum chamber (1).

9. The electron beam additive manufacturing device according to any one of claims 1 to 6, characterized in that: The heat insulation screen (211) is provided with an observation hole.

10. An electron beam additive manufacturing method, characterized in that: Applied to the electron beam additive manufacturing device according to any one of claims 1 to 9, the electron beam additive manufacturing method comprises the following steps: Prepare to spread the powder, the powder spreading and feeding mechanism conveys the metal powder to the powder bed, the driving member (221) drives the heat shield (211) to move in a direction away from the powder bed, so that the heat shield (211) rises, and performs a powder scraping action; The driving member (221) drives the heat shield (211) to move toward the powder bed, so that the heat shield (211) descends and covers the processing area; Preheating printing, so that the electron beam output by the electron gun sintering the metal powder; Repeat the above steps until printing is completed.

Images