A high temperature alloy capillary preparation device and method

Abstract

The present invention belongs to the technical field of single crystal high temperature alloy additive manufacturing, and specifically relates to a high temperature alloy capillary preparation device and method. The device includes a ceramic disk, an upper sealing cover and a lower sealing cover. The ceramic disk is provided with a funnel-shaped through hole, an inner ceramic column core is inserted in the through hole, and a high temperature alloy capillary forming annular cavity is left between the inner ceramic column core and the through hole; the bottom of the ceramic disk is provided with a seed crystal high temperature alloy capillary end and a traction mechanism inserted into the high temperature alloy capillary forming annular cavity; the powder feeding end actuator and the non-contact heating device are respectively used to add single crystal alloy powder to the high temperature alloy capillary forming annular cavity and to heat at high temperature to form a single crystal high temperature alloy molten pool; the traction mechanism pulls the seed crystal high temperature alloy capillary end downward to realize continuous additive preparation of high temperature alloy capillary. The present invention realizes ultra-high temperature gradient by top heating and bottom water-cooling ring cooling, reduces the segregation of single crystal alloy components, and realizes the homogenization of standard material components.

Description

Technical Field

[0001] The present invention belongs to the technical field of single crystal high temperature alloy additive manufacturing, and specifically relates to a high temperature alloy capillary preparation device and method. Background Art

[0002] High-temperature alloy capillaries are heat exchange components for solar energy, nuclear energy and high-speed aircraft. The diameter of high-temperature alloy capillaries is about 0.9 mm and the wall thickness is about 50 μm. The process in the current public literature is micro-machining technology forging, drilling, drawing and annealing alternately. Drawing belongs to tensile stress processing, and lattice and impurity defects are easily magnified, affecting its thermal stress fatigue life of high-temperature creep.

[0003] Nickel-based single crystal high temperature single crystal additive manufacturing belongs to the laser epitaxial growth process and powder bed melting crystal selection process. The key lies in the gradient temperature field, solidification speed and scanning speed control of the process environment. Its crystal selection principle is micro-helix principle + stress (μ+Helix+stress). At present, the thickness of a single layer printing can reach about 2mm. The specific process allows nickel-based single crystal high temperature single crystal additive manufacturing parts to have specific high temperature alloy properties.

[0004] At present, the outer layer of thin-walled curved surfaces produced by laser epitaxial growth process and powder bed melting crystal selection process is impurity crystal, not single crystal. The reason is that the outer surface is more complex than the inner core of the part due to the thermodynamic temperature field of the molten pool fluid mechanics and convection heat dissipation, and the shape of the outer surface molten pool is uncertain. The heat dissipation near the outer surface is a thermodynamic phenomenon of argon turbulent convection heat dissipation. If the impurity crystal layer is removed by subtractive manufacturing, the cost is extremely high, and the removal of the impurity crystal layer by subtractive manufacturing will affect the integrity of the internal nickel-based single crystal high-temperature single crystal metal fiber, and affect its high-temperature oxidation resistance and high-temperature fatigue performance.

[0005] In order to meet the performance requirements of product series, two embodiments are required, one with less segregation and the other with single crystal. Therefore, it is necessary to design a high temperature alloy capillary preparation device and method to meet the above requirements. Summary of the invention

[0006] In view of the above problems, the object of the present invention is to provide a high-temperature alloy capillary preparation device and method to reduce the segregation of single crystal alloy components and achieve homogenization of the standard material composition.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] On one hand, the present invention provides a high-temperature alloy capillary preparation device, comprising a ceramic disk and an upper sealing cover and a lower sealing cover arranged on the upper and lower sides of the ceramic disk, wherein the ceramic disk is provided with a funnel-shaped through hole, an inner ceramic column core is inserted into the through hole, and a high-temperature alloy capillary forming annular cavity is left between the inner ceramic column core and the through hole; a seed crystal high-temperature alloy capillary end inserted into the high-temperature alloy capillary forming annular cavity and a traction mechanism for traction of the seed crystal high-temperature alloy capillary end to be lifted and lowered are provided at the bottom of the ceramic disk;

[0009] A non-contact heating device and a powder feeding end actuator are provided above the ceramic disk. The powder feeding end actuator is used to add single crystal alloy powder into the high temperature alloy capillary forming ring cavity. The non-contact heating device is used to heat the single crystal alloy powder at high temperature to form a single crystal high temperature alloy molten pool.

[0010] There is a high-pressure non-oxygen atmosphere in both the upper sealing cover and the lower sealing cover, and the air pressure in the upper sealing cover is greater than the air pressure in the lower sealing cover. When the traction mechanism pulls the end of the seed crystal high-temperature alloy capillary downward, the single crystal high-temperature alloy molten pool descends under the action of the air pressure difference, thereby realizing continuous additive preparation of the high-temperature alloy capillary on the end of the seed crystal high-temperature alloy capillary.

[0011] In one possible implementation, a water cooling pipe surrounding the lower portion of the through hole is provided in the ceramic disk, and the crystallization temperature gradient field of the single crystal high-temperature alloy molten pool is controlled by the water cooling pipe.

[0012] In one possible implementation, the through hole on the ceramic disk includes a spatial funnel-shaped curved side wall and a cylindrical inner wall arranged vertically, and the seed crystal high-temperature alloy capillary end is initially inserted into the intersection between the spatial funnel-shaped curved side wall and the cylindrical inner wall.

[0013] In a possible implementation, the upper end of the inner ceramic column core is fixed to the ceramic disk via a connecting frame, and the inner ceramic column core is coaxial with the through hole on the ceramic disk.

[0014] In one possible implementation, the non-contact heating device is a laser, which heats the single crystal high-temperature alloy by emitting laser light.

[0015] In a possible implementation, a sensor assembly is provided in the upper sealing cover, and the sensor assembly can collect and monitor the temperature field and size of the single crystal high-temperature alloy molten pool in real time.

[0016] In one possible implementation, the traction mechanism includes a traction wheel I and a traction wheel II clamped on both sides of the seed crystal high-temperature alloy capillary end, and the traction wheel I and the traction wheel II are servo-controlled to rotate in opposite directions, thereby controlling the descent speed of the seed crystal high-temperature alloy capillary end or the additively manufactured seed crystal high-temperature alloy capillary.

[0017] Another aspect of the present invention provides a method for preparing a high-temperature alloy capillary using the above-mentioned preparation device, comprising the following steps:

[0018] Step S1: inserting the seed crystal high-temperature alloy capillary end from the bottom of the ceramic disk into the high-temperature alloy capillary forming ring cavity through a pulling mechanism;

[0019] Step S2: establishing a first argon high pressure zone in the upper sealing cover, establishing a second argon high pressure zone in the lower sealing cover, and making the pressure of the first argon high pressure zone greater than the pressure of the second argon high pressure zone;

[0020] Step S3: The powder delivery end actuator delivers the single crystal high temperature alloy powder into the high temperature alloy capillary forming ring cavity between the inner ceramic column core and the through hole;

[0021] Step S4: heating with a non-contact heating device to form a ring-shaped single crystal high temperature alloy molten pool of the single crystal high temperature alloy powder;

[0022] Step S5: The end of the seed crystal high-temperature alloy capillary is pulled down by a pulling mechanism, and the single crystal high-temperature alloy molten pool follows the downward movement under the action of the argon pressure difference, and the crystallization temperature gradient field of the single crystal high-temperature alloy molten pool is controlled by a water cooling pipe in the ceramic disk;

[0023] Step S6: Through the combined effects of argon pressure difference, high-temperature alloy crystallization temperature gradient field and controllable displacement of the traction mechanism, the single crystal high-temperature alloy molten pool is crystallized and additively manufactured at the top of the seed crystal high-temperature alloy capillary end, thereby achieving continuous and controllable growth of the seed crystal high-temperature alloy capillary.

[0024] In one possible implementation, the single crystal alloy grain growth orientation is <0,0,1>.

[0025] The advantages and beneficial effects of the present invention are as follows: the high-temperature alloy capillary preparation device provided by the present invention realizes ultra-high temperature gradient through top heating and bottom water-cooled ring cooling, accelerates cooling speed, and reduces solute flow through directional solidification unidirectional heat flow control, thereby reducing component segregation and achieving uniformity of standard material composition. At the same time, in the process of crystallization additive manufacturing of seed crystal high-temperature alloy capillary by single crystal high-temperature alloy molten pool, the solidus and liquidus change areas of single crystal high-temperature alloy are not in contact with argon gas, avoiding the influence of molten pool fluid mechanics and thermodynamic temperature field of convection heat dissipation, improving product performance and external surface quality, eliminating the need to remove the impure crystal layer, and reducing production costs.

[0026] The present invention provides a method for preparing a high-temperature alloy capillary. Compared with the capillary high-temperature alloy micro-machining technology of forging, drilling, drawing and annealing, the present method uses argon positive pressure crystallization instead of repeated crystallization under tensile stress. Therefore, it has certain economic efficiency. The length of the high-temperature alloy capillary prepared by the present method is not limited by the size of the raw materials, which is convenient for filling the gap in the field of longer capillary high-temperature alloys.

[0027] Other features and advantages of the present invention will be described in the following description, and partly become apparent from the description, or understood by practicing the present invention. The purpose and other advantages of the present invention can be realized and obtained by the structures particularly pointed out in the written description and the accompanying drawings.

[0028] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0030] Figure 1 It is a structural schematic diagram of a high-temperature alloy capillary preparation device of the present invention;

[0031] Figure 2 for Figure 1 A partial enlarged view in the middle;

[0032] Figure 3 One of the axonometric views of the present invention without the upper and lower sealing covers;

[0033] Figure 4 The second is an axonometric view of the present invention without the upper and lower sealing covers.

[0034] In the figure: 1-seed crystal high-temperature alloy capillary end, 2-single crystal high-temperature alloy molten pool, 3-lower sealing cover, 4-ceramic disk, 401-space funnel-shaped curved side wall, 5-inner ceramic column core, 501-outer cylindrical surface, 6-traction mechanism, 601-traction wheel I, 602-traction wheel II, 7-non-contact heating device, 701-laser, 8-powder feeding end actuator, 801-powder feeding pipe, 9-connecting frame, 10-upper sealing cover, 11-first argon high-pressure zone, 12-second argon high-pressure zone, 13-sensor assembly, 14-water cooling pipeline. DETAILED DESCRIPTION

[0035] In 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, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0036] The preferred embodiments of the present invention are described below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0037] An embodiment of the present invention provides a high-temperature alloy capillary preparation device, which can reduce the segregation of single crystal alloy components and achieve uniformity of the components of standard materials. Figures 1 to 4 As shown, the high-temperature alloy capillary preparation device comprises a ceramic disk 4 and an upper sealing cover 10 and a lower sealing cover 3 arranged on the upper and lower sides of the ceramic disk 4, wherein the ceramic disk 4 is provided with a funnel-shaped through hole, an inner ceramic column core 5 is inserted in the through hole, and a high-temperature alloy capillary forming annular cavity is left between the inner ceramic column core 5 and the through hole; a seed crystal high-temperature alloy capillary end 1 inserted into the high-temperature alloy capillary forming annular cavity and a traction mechanism 6 for traction and lifting of the seed crystal high-temperature alloy capillary end 1 are provided at the bottom of the ceramic disk 4; a non-contact heating device 7 and a powder feeding end actuator are provided above the ceramic disk 4 8. The powder feeding end actuator 8 is used to add single crystal alloy powder into the high-temperature alloy capillary forming ring cavity, and the non-contact heating device 7 is used to heat the single crystal alloy powder at high temperature to form a single crystal high-temperature alloy molten pool 2; the upper sealing cover 10 and the lower sealing cover 3 are both in a high-pressure non-oxygen atmosphere, and the air pressure in the upper sealing cover 10 is greater than the air pressure in the lower sealing cover 3. When the traction mechanism 6 pulls the seed crystal high-temperature alloy capillary end 1 to move downward, the single crystal high-temperature alloy molten pool 2 descends under the action of the air pressure difference, thereby realizing continuous additive preparation of the high-temperature alloy capillary on the seed crystal high-temperature alloy capillary end 1.

[0038] See also Figure 2 As shown, in the embodiment of the present invention, a water cooling pipe 14 surrounding the lower part of the through hole is provided in the ceramic disk 4, and the crystallization temperature gradient field of the single crystal high temperature alloy molten pool 2 is controlled by the water cooling pipe 14.

[0039] In an embodiment of the present invention, the through hole on the ceramic disk 4 includes a space funnel-shaped curved side wall 401 and a cylindrical inner wall arranged up and down, and an annular gap is left between the cylindrical inner wall of the through hole and the outer cylindrical surface 501 of the inner ceramic column core 5. The seed crystal high-temperature alloy capillary end 1 is initially inserted into the intersection between the space funnel-shaped curved side wall 401 and the cylindrical inner wall, thereby closing the bottom of the space funnel-shaped curved side wall 401 to add single crystal alloy powder. Specifically, the powder feeding end actuator 8 is connected to the execution end of the powder feeding robot, and the powder feeding tube 801 is connected to the powder feeding end actuator 8. The powder feeding end actuator 8 conveys single crystal high-temperature alloy powder to the inner side of the space funnel-shaped curved side wall 401 through the powder feeding tube 801.

[0040] In this embodiment, high-pressure argon gas is filled into the upper sealing cover 10 and the lower sealing cover 3, a first argon high-pressure area 11 is formed in the upper sealing cover 10, and a second argon high-pressure area 12 is formed in the lower sealing cover 3, and the pressure of the first argon high-pressure area 11 is greater than the pressure of the second argon high-pressure area 12.

[0041] See also Figure 3 As shown, in an embodiment of the present invention, the upper end of the inner ceramic column core 5 is fixed on the ceramic disk 4 by a connecting frame 9, so that the inner ceramic column core 5 is suspended and fixed relative to the ceramic disk 4, and the inner ceramic column core 5 is coaxial with the through hole on the ceramic disk 4, and the outer diameter of the inner ceramic column core 5 is smaller than the inner diameter of the through hole.

[0042] Preferably, the non-contact heating device 7 is a laser, which heats the single crystal high temperature alloy by emitting laser 701. The key to the laser epitaxial growth process and the powder bed melting crystal selection process lies in the gradient temperature field, solidification speed and scanning speed control of the process environment, and the crystal selection principle is micro-helix principle + stress (μ+Helix+stress).

[0043] Furthermore, a sensor assembly 13 is provided in the upper sealing cover 10 , and the sensor assembly 13 can collect and monitor the temperature field and size of the single crystal high-temperature alloy molten pool 2 in real time.

[0044] See also Figure 1 , Figure 4 As shown, in an embodiment of the present invention, the traction mechanism 6 includes a traction wheel Ⅰ601 and a traction wheel Ⅱ602 clamped on both sides of the seed crystal high-temperature alloy capillary tip 1, and the traction wheel Ⅰ601 and the traction wheel Ⅱ602 are servo-controlled to rotate in opposite directions, thereby controlling the descending position, speed and acceleration of the seed crystal high-temperature alloy capillary tip 1 or the additively manufactured seed crystal high-temperature alloy capillary.

[0045] Preferably, the ceramic disk 4 and the inner ceramic column core 5 are made of a ceramic crucible material made of alumina, zirconia, silicon dioxide or the like.

[0046] Since the pressure of the first argon high-pressure zone 11 is higher than that of the second argon high-pressure zone 12, the single crystal high-temperature alloy molten pool 2 gradually extends and grows at the top of the seed crystal high-temperature alloy capillary end 1, and the internal crystallization process of the single crystal high-temperature alloy molten pool 2 is formed under a certain gas pressure, which helps to reduce the crystallization defects of the cast nickel-based single crystal alloy, and helps to refine the grains and make the single crystal alloy grain growth orientation <0,0,1>.

[0047] An embodiment of the present invention provides a high-temperature alloy capillary preparation device, which realizes an ultra-high temperature gradient and accelerates the cooling rate through top heating and bottom water-cooling ring cooling, and reduces solute flow through directional solidification unidirectional heat flow control, thereby reducing component segregation and achieving homogenization of the standard material composition.

[0048] Based on the above design concept, another embodiment of the present invention provides a method for preparing a high-temperature alloy capillary, which is implemented using the high-temperature alloy capillary preparation device in the above embodiment. Figures 1 to 4 As shown, the preparation method comprises the following steps:

[0049] Step S1: inserting the seed crystal high-temperature alloy capillary end 1 from the bottom of the ceramic disk 4 into the high-temperature alloy capillary forming ring cavity through the traction mechanism 6;

[0050] Step S2: establishing a first argon high pressure area 11 in the upper sealing cover 10, and establishing a second argon high pressure area 12 in the lower sealing cover 3, and making the pressure of the first argon high pressure area 11 greater than the pressure of the second argon high pressure area 12;

[0051] Step S3: the powder feeding end actuator 8 feeds the single crystal high temperature alloy powder into the high temperature alloy capillary forming ring cavity between the inner ceramic column core 5 and the through hole;

[0052] Step S4: The non-contact heating device 7 performs heating to form the single crystal high temperature alloy powder into an annular single crystal high temperature alloy molten pool 2;

[0053] Step S5: The seed crystal high temperature alloy capillary tip 1 is pulled down by the pulling mechanism 6, and the single crystal high temperature alloy molten pool 2 follows the downward movement under the action of the argon pressure difference, and the crystallization temperature gradient field of the single crystal high temperature alloy molten pool 2 is controlled by the water cooling pipe 14 in the ceramic disk 4;

[0054] Specifically, by forming extrusion rolling friction between the traction wheel I 601 and the traction wheel II 602 and the end 1 of the seed crystal high temperature alloy capillary, the descending position, speed and acceleration of the additively manufactured seed crystal high temperature alloy capillary are servo-controlled;

[0055] Step S6: Through the combined effects of the argon pressure difference, the high-temperature alloy crystallization temperature gradient field and the controllable displacement of the traction mechanism 6, the single crystal high-temperature alloy molten pool 2 is crystallized and additively manufactured on the top of the seed crystal high-temperature alloy capillary end 1, thereby achieving continuous and controllable growth of the seed crystal high-temperature alloy capillary.

[0056] Furthermore, the single crystal alloy grain growth orientation is <0,0,1>.

[0057] In this embodiment, the ceramic disk 4 contains a water cooling pipe 14 inside, and the crystallization temperature gradient field of the single crystal high temperature alloy molten pool 2 is controlled by the water cooling pipe 14. The sensor assembly 13 can collect and monitor the temperature field and size of the single crystal high temperature alloy molten pool 2 in real time. Therefore, the control system can use the heat output of the water cooling pipe 14, the non-contact heating device 7, the sensor assembly 13, etc. to form a thermodynamic temperature control system for the single crystal high temperature alloy molten pool 2 to additively manufacture the seed crystal high temperature alloy capillary. The characteristic of the thermodynamic temperature control system is that the single crystal high temperature alloy molten pool 2 crystallization process additively manufactures the seed crystal high temperature alloy capillary, and the single crystal high temperature alloy solid phase line and liquid phase line change area are at the lower part of the space funnel-shaped curved surface side wall 401, which is not in contact with argon gas. The characteristics are determined by contacting the ceramic curved surface rules, avoiding the influence of the thermodynamic temperature field of the molten pool fluid mechanics and convection heat dissipation, improving product performance and outer surface quality, and no longer needing to remove the impure crystal layer, reducing production costs. In this embodiment, the diameter of the prepared high temperature alloy capillary is 0.9 mm and the wall thickness is 50 μm.

[0058] Another embodiment of the present invention provides a method for preparing a high-temperature alloy capillary, which achieves an ultra-high temperature gradient and accelerates the cooling rate through top heating and bottom water-cooling ring cooling, as well as directional solidification unidirectional heat flow control to reduce solute flow, thereby reducing component segregation and achieving uniformity of the standard material composition. Compared with the capillary high-temperature alloy micro-machining technology of forging, drilling, drawing and annealing alternating forming, this method is argon positive pressure crystallization, rather than repeated crystallization under tensile stress. Therefore, it has certain economy. The high-temperature alloy capillary prepared by this method has a length that is not limited by the size of the raw materials, which is convenient for filling the gap in the field of longer capillary high-temperature alloys.

[0059] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A high temperature alloy capillary preparation device, characterized in that: The invention comprises a ceramic disk (4) and an upper sealing cover (10) and a lower sealing cover (3) arranged on the upper and lower sides of the ceramic disk (4), wherein the ceramic disk (4) is provided with a funnel-shaped through hole, an inner ceramic column core (5) is inserted into the through hole, and a high-temperature alloy capillary forming annular cavity is left between the inner ceramic column core (5) and the through hole; a seed crystal high-temperature alloy capillary end (1) inserted into the high-temperature alloy capillary forming annular cavity and a traction mechanism (6) for traction of the seed crystal high-temperature alloy capillary end (1) are provided at the bottom of the ceramic disk (4); A non-contact heating device (7) and a powder delivery end actuator (8) are provided above the ceramic disk (4); the powder delivery end actuator (8) is used to add single crystal high temperature alloy powder into the high temperature alloy capillary forming ring cavity; the non-contact heating device (7) is used to heat the single crystal high temperature alloy powder at a high temperature to form a single crystal high temperature alloy molten pool (2); The upper sealing cover (10) and the lower sealing cover (3) are both filled with a high-pressure non-oxygen atmosphere, and the air pressure in the upper sealing cover (10) is greater than the air pressure in the lower sealing cover (3). When the traction mechanism (6) tractions the seed crystal high-temperature alloy capillary end (1) to move downward, the single crystal high-temperature alloy molten pool (2) descends under the action of the air pressure difference, thereby realizing continuous additive preparation of the high-temperature alloy capillary on the seed crystal high-temperature alloy capillary end (1); A water cooling pipe (14) surrounding the lower part of the through hole is provided in the ceramic disk (4), and the crystallization temperature gradient field of the single crystal high temperature alloy molten pool (2) is controlled by the water cooling pipe (14); The through hole on the ceramic disk (4) comprises a space funnel-shaped curved side wall (401) and a cylindrical inner wall arranged up and down, and the seed crystal high-temperature alloy capillary end (1) is initially inserted into the intersection between the space funnel-shaped curved side wall (401) and the cylindrical inner wall.

2. The high temperature alloy capillary preparation device according to claim 1, characterized in that: The upper end of the inner ceramic column core (5) is fixed to the ceramic disk (4) via a connecting frame (9), and the inner ceramic column core (5) is coaxial with a through hole on the ceramic disk (4).

3. The high temperature alloy capillary preparation device according to claim 1, characterized in that: The non-contact heating device (7) is a laser, and the laser heats the single crystal high-temperature alloy powder by emitting laser light (701).

4. The high temperature alloy capillary preparation device according to claim 1, characterized in that: The traction mechanism (6) comprises a traction wheel I (601) and a traction wheel II (602) clamped on both sides of the seed crystal high-temperature alloy capillary end (1), and the traction wheel I (601) and the traction wheel II (602) are servo-controlled to rotate in opposite directions, thereby controlling the descending speed of the seed crystal high-temperature alloy capillary end (1) or the additively manufactured seed crystal high-temperature alloy capillary.

5. A method for preparing a high-temperature alloy capillary using the device according to any one of claims 1 to 4, characterized in that: The following steps are involved: Step S1: inserting the seed crystal high-temperature alloy capillary end (1) from the bottom of the ceramic disk (4) into the high-temperature alloy capillary forming ring cavity through the pulling mechanism (6); Step S2: establishing a first argon high pressure zone (11) in the upper sealing cover (10), and establishing a second argon high pressure zone (12) in the lower sealing cover (3), and making the pressure of the first argon high pressure zone (11) greater than the pressure of the second argon high pressure zone (12); Step S3: the powder delivery end actuator (8) delivers the single crystal high temperature alloy powder into the high temperature alloy capillary forming ring cavity between the inner ceramic column core (5) and the through hole; Step S4: the non-contact heating device (7) performs heating to form a ring-shaped single crystal high temperature alloy molten pool (2) from the single crystal high temperature alloy powder; Step S5: the seed crystal high temperature alloy capillary end (1) is pulled downward by the pulling mechanism (6), and the single crystal high temperature alloy molten pool (2) follows the downward movement under the action of the argon pressure difference, and the crystallization temperature gradient field of the single crystal high temperature alloy molten pool (2) is controlled by the water cooling pipe (14) in the ceramic disk (4); Step S6: Through the combined effects of the argon pressure difference, the high-temperature alloy crystallization temperature gradient field and the controllable displacement of the traction mechanism (6), the single crystal high-temperature alloy molten pool (2) is crystallized and additively manufactured on the top of the seed crystal high-temperature alloy capillary end (1), thereby achieving continuous and controllable growth of the high-temperature alloy capillary.

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