Low-deformation directional energy deposition method for space Laval generatrix revolving body structure
By employing a directional energy deposition method that combines symmetrical and alternating busbar and circumferential directions with infrared thermometry, the problem of large deformation in the space Laval busbar rotating structure was solved, enabling the manufacture of a high-precision bimetallic combustion chamber.
Patent Information
- Application Number
- CN202511584588.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-31
- Publication Date
- 2026-02-13
AI Technical Summary
In the existing technology, the spatial Laval busbar rotating structure has a large deformation problem during the directional energy deposition process, especially during the forming of the outer wall of the copper alloy inner wall, which leads to limited accuracy of the combustion chamber.
A directional energy deposition method with symmetrical busbar and alternating busbar-circumferential directions is adopted. The paths of odd-numbered layers and even-numbered layers are designed to be different. The odd-numbered layers have the same path as the first layer, and the even-numbered layers have the same path as the second layer. The temperature of each layer after formation is controlled by an infrared thermometer, and directional energy deposition is carried out layer by layer.
This effectively reduced deformation, improved the forming accuracy of the combustion chamber, ensured the quality of the outer wall, and achieved high-precision manufacturing of the bimetallic combustion chamber.
Smart Images
Figure CN121514523A_ABST
Abstract
Description
Technical Field
[0001] This invention belongs to the field of additive manufacturing technology and relates to a low-deformation directional energy deposition method for a spatial Laval generatrix rotating structure. Background Technology
[0002] Laser melting deposition technology is an additive manufacturing technology that uses lasers, electric arcs, or electron beams as heat sources and metal powder / welding wire as raw materials. It involves coaxially or off-axis feeding the metal powder or wire into a molten pool, layer by layer, to create a composite material. It features high deposition efficiency and the ability to manufacture dissimilar metals and graded functional / dissimilar metal materials. The combustion chamber is a core component of a liquid rocket engine, operating under harsh conditions. To ensure stable engine operation, combustion chambers mostly employ a bimetallic structure: the inner wall profile is a spatial Laval generatrix rotating body, with an internal regenerative cooling channel design, and the material is mostly a copper alloy with high thermal conductivity to achieve rapid cooling of the combustion gases; the outer wall is generally made of high-temperature alloys or stainless steel to ensure the overall structural strength of the combustion chamber.
[0003] When using powder-directed energy deposition (EDD) combined additive manufacturing to manufacture engine combustion chambers, the copper alloy inner wall is integrally formed within the cooling channel structure using powder-based selective laser melting (SLM) technology. The high-temperature alloy or stainless steel outer wall is formed on the surface of the inner copper alloy using powder-feeding or wire-feeded EDD. Due to the high thermal conductivity of copper alloys, directional energy deposition on the outer wall requires a large energy input. This large energy input leads to significant deformation of the copper inner wall of the spatial curved generatrix, particularly at the throat of the copper inner wall generatrix and the spatial Laval generatrix, where the maximum deformation can reach 5%. This severely affects the accuracy of the combustion chamber and limits the application of combined additive manufacturing technology in the overall manufacturing of combustion chambers. Summary of the Invention
[0004] The technical problem solved by this invention is to overcome the shortcomings of the prior art and propose a low-deformation directional energy deposition method for a space Laval busbar rotating body structure. This method solves the technical problem of large deformation in the directional energy deposition of the space Laval busbar rotating body structure and achieves high-precision forming of the bimetallic combustion chamber.
[0005] The solution of the present invention is:
[0006] A low-deformation directional energy deposition method for a space Laval generatrix rotating structure includes:
[0007] Select the copper alloy inner wall structure of the engine combustion chamber to be deposited and formed;
[0008] Using the copper alloy inner wall structure as a substrate, a first-layer directional energy deposition path was designed;
[0009] Design the second layer of the directed energy deposition path based on the first layer of the directed energy deposition path;
[0010] In this way, the i+1 layer of the directed energy deposition path is designed based on the i layer of the directed energy deposition path; until the design of all layers of the directed energy deposition path is completed; wherein, starting from the third layer of the directed energy deposition path, the design method of the odd layer of the directed energy deposition path is the same as that of the first layer of the directed energy deposition path; the design method of the even layer of the directed energy deposition path is the same as that of the second layer of the directed energy deposition path;
[0011] Install the copper alloy inner wall structure on the positioner of the directed energy deposition equipment;
[0012] According to the design of all layers of the directed energy deposition path, perform directed energy deposition layer by layer; until the final outer wall is formed.
[0013] In the above-mentioned low-deformation directed energy deposition method of a spatial Laval bus of revolution structure, the copper alloy inner wall structure is a spatial Laval bus of revolution structure.
[0014] In the above-mentioned low-deformation directed energy deposition method of a spatial Laval bus of revolution structure, the method of the first layer of the directed energy deposition path is:
[0015] S21, select an arbitrary bus of the outer wall of the copper alloy inner wall structure as the first forming path;
[0016] S22, select a bus at a position 180° apart from the first forming path as the second forming path;
[0017] S23, select a bus at a position 90° apart from the second forming path as the third forming path;
[0018] S24, select a bus at a position 180° apart from the third forming path as the fourth forming path;
[0019] S25, set the melt width of the directed energy deposition as w; and set the fifth forming path on one side of the first forming path;
[0020] S26, select a bus at a position 180° apart from the fifth forming path as the sixth forming path;
[0021] S27, set the seventh forming path on one side of the fifth forming path;
[0022] S28, select a bus at a position 180° apart from the seventh forming path as the eighth forming path;
[0023] Similarly, the generatrix at a position 180° apart from the kth forming path is selected as the (k+1)th forming path; the (k+2)th forming path is arranged on one side of the kth forming path; k is an odd number not less than 7; until the design of the first layer of the directional energy deposition path is completed.
[0024] In the low-deformation directional energy deposition method of the spatial Laval generatrix rotary body structure, in the S25, the melt width of the first forming path and the melt width of the fifth forming path are overlapped; the overlap rate is 30%-40%.
[0025] In the low-deformation directional energy deposition method of the spatial Laval generatrix rotary body structure, starting from the fifth forming path, the subsequent odd-numbered forming paths are arranged on one side of the previous odd-numbered forming path; the subsequent even-numbered forming paths are arranged at positions 180° apart from the previous odd-numbered forming paths.
[0026] In the low-deformation directional energy deposition method of the spatial Laval generatrix rotary body structure, the design method of the second layer of the directional energy deposition path is:
[0027] S31, a circumferential annular path at the small-diameter opening end of the copper alloy inner wall structure on the outer wall of the first layer of the directional energy deposition path is selected as the first forming path;
[0028] S32, a second forming path is arranged on the outer side of the first forming path along the generatrix;
[0029] Similarly, a (j+1)th forming path is arranged on the outer side of the jth forming path along the generatrix; until the design of the second layer of the directional energy deposition path is completed.
[0030] In the low-deformation directional energy deposition method of the spatial Laval generatrix rotary body structure, in the S32, the second forming path is an annular path; the melt width of the directional energy deposition is set as w; the melt width of the second forming path and the melt width of the first forming path are overlapped; the overlap rate is 30%-40%.
[0031] In the low-deformation directional energy deposition method of the spatial Laval generatrix rotary body structure, it is set that the design of n layers of the directional energy deposition path is completed; n is a positive integer not less than 2; the melt height of the directional energy deposition is set as h; the total energy deposition thickness is set as H; then H=n×h.
[0032] In the low-deformation directional energy deposition method of the spatial Laval generatrix rotary body structure, when the directional energy deposition is performed layer by layer, after each layer is completed, an infrared temperature measuring instrument is used to test the surface after forming; when the temperature is lower than 300℃, the directional energy deposition of the next layer is started.
[0033] In the space Laval bus rotary body structure low deformation directional energy deposition method, the directional energy deposition material is high-temperature alloy or stainless steel.
[0034] Compared with the prior art, the present application has the following beneficial effects:
[0035] (1) The bus symmetry and bus-circumferential alternating forming strategy can reduce the deformation by 70% compared with the commonly used circumferential spiral and circumferential layer-by-layer forming strategy.
[0036] (2) After completing each layer forming, the present application uses an infrared temperature detector to test the surface after forming, and when the temperature is lower than 300 DEG C, the forming of the next layer is started, so as to ensure the quality of the outer wall.
[0037] (3) When the odd layer path is designed, the odd layer path is set, and the even layer path is set at 180 DEG, so as to prevent the instability caused by the adjacent setting. BRIEF DESCRIPTION OF DRAWINGS
[0038] Figure 1 It is a first layer first path forming diagram of the present application;
[0039] Figure 2 It is a first layer second path forming diagram of the present application;
[0040] Figure 3 It is a first layer third path forming diagram of the present application;
[0041] Figure 4 It is a first layer directional energy deposition path overall diagram of the present application;
[0042] Figure 5 It is a first layer first path forming diagram of the present application;
[0043] Figure 6 It is a first layer second path forming diagram of the present application. DETAILED DESCRIPTION
[0044] The present application will be further described below in combination with the embodiments.
[0045] The present application provides a space Laval bus rotary body structure low deformation directional energy deposition method, which solves the technical problem of large deformation of space Laval bus rotary body structure directional energy deposition, and realizes high-precision forming of a bimetallic combustion chamber.
[0046] The space Laval bus rotary body structure low deformation directional energy deposition method specifically includes the following steps:
[0047] The copper alloy inner wall structure of the engine combustion chamber to be deposited and formed is selected. The copper alloy inner wall structure is a spatial Laval generatrix revolution body structure.
[0048] The first layer of directional energy deposition path is designed based on the copper alloy inner wall structure.
[0049] The method of the first layer of directional energy deposition path is as follows:
[0050] S21, an arbitrary generatrix on the outer wall of the copper alloy inner wall structure is selected as the first forming path, as shown in Figure 1 .
[0051] S22, a generatrix at a position 180° apart from the first forming path is selected as the second forming path, as shown in Figure 2 .
[0052] S23, a generatrix at a position 90° apart from the second forming path is selected as the third forming path.
[0053] S24, a generatrix at a position 180° apart from the third forming path is selected as the fourth forming path, as shown in Figure 3 .
[0054] S25, the melt width of the directional energy deposition is set as w; the fifth forming path is arranged on one side of the first forming path. The melt width of the first forming path and the melt width of the fifth forming path are overlapped. The overlap rate is 30%-40%.
[0055] S26, a generatrix at a position 180° apart from the fifth forming path is selected as the sixth forming path.
[0056] S27, the seventh forming path is arranged on one side of the fifth forming path.
[0057] S28, a generatrix at a position 180° apart from the seventh forming path is selected as the eighth forming path.
[0058] In this way, a generatrix at a position 180° apart from the kth forming path is selected as the k+1th forming path; the k+2th forming path is arranged on one side of the kth forming path; k is an odd number not less than 7; until the design of the first layer of directional energy deposition path is completed, as shown in Figure 4 .
[0059] From the fifth forming path, the subsequent odd-numbered forming paths are arranged on one side of the previous odd-numbered forming path; the subsequent even-numbered forming paths are arranged at positions 180° apart from the previous odd-numbered forming paths.
[0060] The second layer of directional energy deposition path is designed based on the first layer of directional energy deposition path.
[0061] The design method of the second layer of the directional energy deposition path is:
[0062] S31, on the outer wall of the first layer of the directional energy deposition path, a circumferential annular path at the small diameter opening end of the copper alloy inner wall structure is selected as the first forming path, as shown in Figure 5 .
[0063] S32, a second forming path is arranged on one side of the first forming path along the generatrix, as shown in Figure 6 .
[0064] The second forming path is an annular path; the melt width of the directional energy deposition is w; the melt width of the second forming path and the melt width of the first forming path exist in the lap joint condition; the lap joint rate is 30%-40%.
[0065] By analogy, the j+1th forming path is arranged on the outside of the jth forming path along the generatrix; until the design of the second layer of the directional energy deposition path is completed.
[0066] By analogy, the i+1th layer of the directional energy deposition path is designed based on the ith layer of the directional energy deposition path; until the design of all layers of the directional energy deposition path is completed; wherein, starting from the third layer of the directional energy deposition path, the design method of the odd layer of the directional energy deposition path is the same as that of the first layer of the directional energy deposition path; the design method of the even layer of the directional energy deposition path is the same as that of the second layer of the directional energy deposition path. Starting from the third layer of the directional energy deposition path, the design method of the odd layer of the directional energy deposition path is the same as that of the first layer of the directional energy deposition path; the design method of the even layer of the directional energy deposition path is the same as that of the second layer of the directional energy deposition path; until the design of all layers of the directional energy deposition path is completed.
[0067] It is set that the design of n layers of the directional energy deposition path is completed; n is a positive integer not less than 2; the melt height of the directional energy deposition is set as h; the total energy deposition thickness is set as H; then H=n×h.
[0068] The copper alloy inner wall structure is installed on the positioner of the directional energy deposition equipment;
[0069] According to the design of all layers of the directional energy deposition path, directional energy deposition is carried out layer by layer; until the final outer wall is formed.
[0070] When directional energy deposition is carried out layer by layer, after each layer is completed, an infrared temperature measuring instrument is used to test the surface after forming; when the temperature is lower than 300℃, the directional energy deposition of the next layer is started. The material of the directional energy deposition is high-temperature alloy or stainless steel.
[0071] The low-deformation directed energy deposition method for the space Laval bus rotary body structure mainly includes two stages of forming strategy making and additive manufacturing.
[0072] Step one: directed energy deposition strategy making
[0073] The directed energy deposition strategy is made for the space Laval bus rotary body structure. First, a single-path process test is conducted on a flat plate using process parameters to determine the single-path forming height h and width w, which are used as reference data for making the deposition strategy. The first layer of the directed energy deposition strategy adopts the bus forming strategy, and the bus forming path is made on the space Laval bus rotary body structure according to the profile of the bus. After setting the first forming path, the second forming path is set at the axially symmetric position of the rotary body surface at an interval of 180°. After setting the second path, the third forming path is set at an interval of 90° in the circumferential direction. The fourth path is set at an interval of 180° from the third path in the circumferential direction. In this way, the even-numbered paths are set at the axially symmetric positions of the previous odd-numbered paths at an interval of 180° in the circumferential direction. Starting from the fifth path, the odd-numbered paths are set beside the first path, and the overlap rate between the two paths is set to 30%-40%. After completing the first layer setting, the second layer forming path is set. The strategy for the second layer is circumferential forming, that is, each forming path is perpendicular to the forming path of the previous layer, and the overlap rate between each path is set to 30%-40%. In this way, the odd-numbered layers adopt the bus forming strategy, and the even-numbered layers adopt the circumferential forming strategy.
[0074] Step two: additive manufacturing
[0075] After the space Laval bus rotary body structure is installed on the positioning machine of the directed energy deposition equipment, the forming paths are set layer by layer in the directed energy deposition path planning software according to the strategy made in step one. After completing the setting, the outer wall is formed. After each layer is formed, an infrared temperature measuring instrument is used to test the formed surface, and when the temperature is lower than 300℃, the next layer of forming is started, until the final manufacturing of the high-temperature alloy or stainless steel outer wall is completed.
[0076] The bus symmetry and bus-circumferential alternating forming strategy proposed in the application can reduce the deformation by 70% compared with the commonly used circumferential spiral and circumferential layer-by-layer forming strategies.
[0077] After each layer is formed in the application, an infrared temperature measuring instrument is used to test the formed surface, and when the temperature is lower than 300℃, the next layer of forming is started, which ensures the quality of the formed outer wall.
[0078] In the path design for the odd-numbered layers, the even-numbered paths are set at an interval of 180° after the odd-numbered paths are set, which prevents the instability caused by the adjacent setting.
[0079] Although the present application has been disclosed with reference to the preferred embodiments, it is not intended to limit the present application, and any person skilled in the art can make possible changes and modifications to the technical solutions of the present application using the disclosed methods and technical contents without departing from the spirit and scope of the present application. Therefore, any simple modification, equivalent change and modification made to the above embodiments according to the technical essence of the present application without departing from the technical solutions of the present application shall fall within the protection scope of the technical solutions of the present application.
Claims
1. A method of low deformation directed energy deposition of a space ravels mother line swivel body structure, characterized by: The application relates to a method for forming an engine combustion chamber by depositing a copper alloy inner wall structure. The method comprises the following steps: selecting a copper alloy inner wall structure of an engine combustion chamber to be formed; designing a first layer of directional energy deposition paths based on the copper alloy inner wall structure; designing a second layer of directional energy deposition paths based on the first layer of directional energy deposition paths; designing an i+1 layer of directional energy deposition paths based on an i layer of directional energy deposition paths; designing all layers of directional energy deposition paths until the design of the first layer of directional energy deposition paths is completed; wherein, starting from the third layer of directional energy deposition paths, the design method of the odd layer of directional energy deposition paths is the same as that of the first layer of directional energy deposition paths; the design method of the even layer of directional energy deposition paths is the same as that of the second layer of directional energy deposition paths; mounting the copper alloy inner wall structure on a directional energy deposition device positioner; 2. A method of low deformation directed energy deposition of a spatial LaVal mother line of revolution structure according to claim 1, characterized in that: carrying out directional energy deposition layer by layer according to the design of all layers of directional energy deposition paths until the final outer wall is formed.
3. A method of low deformation directed energy deposition of a spatial LaVal mother line of revolution structure according to claim 2, characterized in that: The copper alloy inner wall structure is a spatial Laval bus body of revolution structure. The method for designing the first layer of directional energy deposition paths comprises the following steps: S21, selecting an arbitrary bus as a first forming path on the outer wall of the copper alloy inner wall structure; S22, selecting a bus at a position 180 degrees away from the first forming path as a second forming path; S23, selecting a bus at a position 90 degrees away from the second forming path as a third forming path; S24, selecting a bus at a position 180 degrees away from the third forming path as a fourth forming path; S25, setting the melt width of directional energy deposition as w; and arranging a fifth forming path on one side of the first forming path; S26, selecting a bus at a position 180 degrees away from the fifth forming path as a sixth forming path; S27, arranging a seventh forming path on one side of the fifth forming path; S28, selecting a bus at a position 180 degrees away from the seventh forming path as an eighth forming path; 4. A method of low deformation directed energy deposition of a spatial LaVal mother line of revolution structure according to claim 3, characterized in that: S29, selecting a bus at a position 180 degrees away from the kth forming path as a k+1th forming path; and arranging a k+2th forming path on one side of the kth forming path; k is an odd number not less than 7; and the design of the first layer of directional energy deposition paths is completed.
5. A method of low deformation directed energy deposition of a spatial LaVal mother line of revolution structure according to claim 3, characterized in that: In S25, the melt width of the first forming path and the melt width of the fifth forming path are overlapped; and the overlapping rate is 30%-40%.
6. A method of low deformation directed energy deposition of a spatial LaVal mother line of revolution structure according to claim 2, characterized in that: Starting from the fifth forming path, subsequent odd number forming paths are arranged on one side of the previous odd number forming path; and subsequent even number forming paths are arranged at positions 180 degrees away from the previous odd number forming path. The design method of the second layer of directional energy deposition paths comprises the following steps: S31, selecting a circumferential annular path at a small-diameter opening end of the copper alloy inner wall structure as a first forming path on the outer wall of the first layer of directional energy deposition paths; S32, arranging a second forming path on the outer side of the first forming path along the bus; 7. A method of low deformation directed energy deposition of a spatial LaVal mother line of revolution structure according to claim 6, characterized in that: S33, arranging a j+1th forming path on the outer side of a jth forming path along the bus; and the design of the second layer of directional energy deposition paths is completed. In S32, the second forming path is an annular path. The melt width of the directional energy deposition is set as w; the melt width of the second forming path overlaps the melt width of the first forming path; the overlap rate is 30%-40%.
8. A method of low deformation directed energy deposition of a spatial LaVal mother line of revolution structure according to claim 1, characterized in that: The design of the directional energy deposition paths for n layers is set; n is a positive integer not less than 2. The melt height of the directional energy deposition is set as h; the total energy deposition thickness is set as H; then H=n×h.
9. A method of low deformation directed energy deposition of a spatial LaVal mother line of revolution structure according to claim 1, characterized in that: When the directional energy deposition is performed layer by layer, after each layer is completed, the surface after forming is tested by using an infrared temperature detector; when the temperature is lower than 300 DEG C, the directional energy deposition of the next layer is started.
10. A method of low deformation directed energy deposition of a spatial LaVal mother line of revolution structure according to claim 9, characterized in that: The material of the directional energy deposition is a high-temperature alloy or stainless steel.