Integrated precision additive manufacturing method for high-strength aluminum alloy curved inner flow channel components

Abstract

The present invention relates to an integrated precision additive manufacturing method for a high-strength aluminum alloy curved inner flow channel component. The integrated precision additive manufacturing method for the high-strength aluminum alloy curved inner flow channel component uses a laser and electron beam composite printing method to obtain the parts of the high-strength aluminum alloy curved inner flow channel component with high dimensional accuracy requirements, and uses an electron beam printing method to obtain other parts of the high-strength aluminum alloy curved inner flow channel component with high mechanical strength requirements and high manufacturing efficiency. By combining electron beam printing and laser printing, a high-strength alloy curved inner flow channel component with high dimensional accuracy and excellent mechanical properties is obtained. The steps of evacuating, flushing with inert protective gas, and evacuating the working chamber are performed to further improve the mechanical strength of the high-strength aluminum alloy curved inner flow channel component. By performing the furnace cooling step, the printing safety is improved, the probability of the surface of the integrated precision manufactured component being oxidized during the cooling process is reduced, and the product dimensional accuracy is further guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and in particular to an integrated precision additive manufacturing method for a high-strength aluminum alloy curved inner flow channel component. Background Art

[0002] High-strength aluminum alloy inner flow channel components are widely used in aerospace, military manufacturing and other fields. Traditional high-strength aluminum alloy inner flow channel components are often formed by machining and punching, but due to the length and shape of the tool, the components manufactured by machining process mainly have the following problems: 1. The inner flow channel is straight, and the 90° corner will aggravate the air pressure attenuation in the flow channel; 2. Long inner flow channel components must be manufactured in sections and then assembled and formed. Multiple assemblies have the risk of substandard positioning accuracy and low part qualification rate; 3. The existence of process holes requires a large design margin for the wall thickness of the component. The above redundant mass hinders the improvement of the effective filling ratio.

[0003] As products in aerospace, military manufacturing and other fields develop towards lightweight and high strength, it has become a mainstream trend to design high-strength aluminum alloy inner flow channel components from straight channels to curved channels. However, curved inner flow channel components cannot be manufactured using machining and punching processes.

[0004] Additive manufacturing is an effective method to achieve integrated forming of complex and special-shaped metal parts. At present, the mainstream processes of additive manufacturing include five types: laser selective melting, electron beam selective melting, laser melt deposition, electron beam free forming and arc additive manufacturing. Among them, although the aluminum alloy parts formed by laser additive manufacturing process (laser selective melting, laser melt deposition) have high dimensional accuracy, they are prone to cracks, and the strength of the parts is difficult to meet the strength requirements of gas systems in the current aerospace, military manufacturing and other fields; while the aluminum alloy parts formed by processes such as electron beam selective melting, electron beam free deposition and arc additive manufacturing have high surface roughness, and the dimensional accuracy cannot meet the dimensional accuracy requirements of gas systems in the current aerospace, military manufacturing and other fields. Summary of the invention

[0005] Based on the problem that traditional additive manufacturing processes cannot achieve high strength, high processing efficiency and high dimensional accuracy when manufacturing aluminum alloy curved inner flow channel components, it is necessary to provide an integrated precision additive manufacturing method for high-strength aluminum alloy curved inner flow channel components that can improve the strength and dimensional accuracy of aluminum alloy components.

[0006] An integrated precision additive manufacturing method for a high-strength aluminum alloy curved inner flow channel component comprises the following steps:

[0007] Establish a 3D printing model of a high-strength aluminum alloy curved inner flow channel component;

[0008] Marking the three-dimensional printed model according to whether the surface of the high-strength aluminum alloy curved inner flow channel component can be machined and the design accuracy of the non-machinable parts, so as to mark the electron beam printed part and the laser / electron beam composite printed part on the three-dimensional printed model;

[0009] The working chamber of the electron beam / laser powder bed composite melting forming equipment is sequentially evacuated, filled with inert protective gas, and evacuated for a preset number of times;

[0010] Start the powder spreading system of the electron beam / laser powder bed composite melting forming equipment to spread the high-strength aluminum alloy powder flat;

[0011] Starting the electron beam generating system of the electron beam / laser powder bed composite melting forming equipment to preheat the powder bed after powder spreading to a preset temperature;

[0012] Start the laser optical path system of the electron beam / laser powder bed composite fusion forming device, use the electron beam generation system to perform layered printing according to the electron beam printing part, and use the electron beam generation system and the laser pipeline system to perform layered printing according to the laser / electron beam composite printing part to obtain an integrated precision manufacturing component;

[0013] Cooling the integrated precision-manufactured component to room temperature in the working chamber along with the furnace;

[0014] Filling the working chamber with an inert protective gas until the air pressure in the working chamber is equal to the external atmospheric pressure;

[0015] The door of the working chamber is opened to take out the cooled integrated precision-manufactured component.

[0016] In one embodiment, the step of marking the electron beam printed part and the laser / electron beam composite printed part on the three-dimensional printed model comprises:

[0017] Marking a machinable portion of the surface of the three-dimensional printed model corresponding to the high-strength aluminum alloy curved inner flow channel component as the electron beam printed portion;

[0018] Marking a portion of the non-machinable portion of the surface of the high-strength aluminum alloy curved inner flow channel component on the three-dimensional printing model whose dimensional accuracy absolute value is greater than a preset accuracy absolute value as the electron beam printed portion;

[0019] The portion of the non-machinable portion of the surface corresponding to the high-strength aluminum alloy curved inner flow channel component in the three-dimensional printing model whose dimensional accuracy absolute value is less than or equal to the preset accuracy absolute value is marked as a laser / electron beam composite printing portion.

[0020] In one embodiment, the laser / electron beam composite processing portion includes a laser printing layer and an electron beam printing layer;

[0021] Marking the area where the absolute value of the dimensional accuracy of the non-machinable part of the surface of the high-strength aluminum alloy curved inner flow channel component on the three-dimensional printing model is less than or equal to the absolute value of the preset accuracy, and where the depth of the non-machinable surface extending toward the core is less than the preset depth value as the laser printing layer;

[0022] The area on the three-dimensional printing model corresponding to the non-machinable part of the surface of the high-strength aluminum alloy curved inner flow channel component, where the absolute value of the dimensional accuracy is less than or equal to the preset absolute value of the accuracy, and the area where the non-machinable surface extends toward the core to a depth greater than or equal to the preset depth value is marked as the electron beam printing layer.

[0023] In one of the embodiments, the absolute value of the preset precision is ≤0.2 mm.

[0024] In one embodiment, in the laser / electron beam composite printing part, the preset depth is 0.3 mm to the thickness value of the corresponding part. In one embodiment, after the step of opening the door of the working chamber and taking out the cooled formed part, the step further includes:

[0025] The inner flow channel of the formed part is flushed with high-pressure fluid until no powder residue or slag is left in the inner flow channel.

[0026] In one embodiment, the preset temperature is ≤500°C.

[0027] In one embodiment, the preset number of times is ≥ 2 times.

[0028] In one embodiment, when performing the layer-by-layer printing step, the pressure in the working chamber is less than 8×10 -3 Pa; and / or

[0029] When performing the printing step, the printing layer thickness is 40 μm to 100 μm; and / or

[0030] When executing the printing step, the laser scanning speed is 600 mm / s to 1400 mm / s, and the electron beam scanning speed is 750 mm / s to 1250 mm / s.

[0031] In one embodiment, the particle size of the high-strength aluminum alloy powder is 40 μm to 150 μm.

[0032] The above-mentioned integrated precision additive manufacturing method of the high-strength aluminum alloy curved inner flow channel component is to establish a three-dimensional printing model and mark the electron beam printing part and the laser / electron beam composite printing part on the three-dimensional printing model, and use the laser and electron beam composite printing method to obtain the parts with high dimensional accuracy requirements on the high-strength aluminum alloy curved inner flow channel component, and use the electron beam printing method to obtain other parts with high mechanical strength requirements and high manufacturing efficiency on the high-strength aluminum alloy curved inner flow channel component. Therefore, the above-mentioned additive manufacturing method combines electron beam printing and laser printing to obtain a high-strength alloy curved inner flow channel component with high dimensional accuracy and excellent mechanical properties. Before executing the printing step, the steps of vacuuming, flushing with inert protective gas, and vacuuming are performed in the working cabin to ensure an excellent vacuum environment in the working cabin during the printing process, and further improve the mechanical properties of the high-strength aluminum alloy curved inner flow channel component. After the printing is completed, the step of furnace cooling is performed to improve the printing safety while reducing the probability of surface oxidation of the integrated precision manufacturing component during the cooling process, further ensuring the dimensional accuracy of the product.

[0033] Practice has proved that the high-strength aluminum alloy curved inner flow channel component obtained by the above-mentioned integrated precision additive manufacturing method of the high-strength aluminum alloy curved inner flow channel component has a tensile strength of ≥420MPa, a fracture elongation of ≥8%, and a dimensional accuracy better than ±0.2mm. Compared with the traditional "profile + machining" process, the formability of the curved inner flow channel structure is better.

[0034] Therefore, the use of the above-mentioned integrated precision additive manufacturing method of high-strength aluminum alloy curved inner flow channel components can obtain high-strength aluminum alloy curved inner flow channel components that have both high dimensional accuracy and high mechanical strength, so as to meet the dimensional accuracy requirements and mechanical strength requirements of components such as gas systems in the current aerospace, military manufacturing and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a schematic diagram of the process of an integrated precision additive manufacturing method of a high-strength aluminum alloy curved inner flow channel component in a preferred embodiment of the present invention;

[0036] Figure 2 for Figure 1 The schematic diagram of the process of step S50 in the integrated precision additive manufacturing method of the high-strength aluminum alloy curved inner flow channel component is shown;

[0037] Figure 3 for Figure 1 The flowchart of step S90 in the integrated precision additive manufacturing method of the high-strength aluminum alloy curved inner flow channel component is shown. DETAILED DESCRIPTION

[0038] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. Preferred embodiments of the present invention are provided in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0040] When describing positional relationships, unless otherwise specified, when an element is referred to as being "on" another element, it can be directly on the other element or there can be an intermediate element. It is also understood that when an element is referred to as being "between" two elements, it can be the only one between the two elements, or there can be one or more intermediate elements.

[0041] In the case of using “including”, “having”, and “comprising” described herein, another component may be added unless a clear limiting term such as “only”, “consisting of”, etc. is used. Unless mentioned otherwise, a term in the singular form may include a plural form and should not be understood as being one in number.

[0042] See also Figure 1 The integrated precision additive manufacturing method of the high-strength aluminum alloy curved inner flow channel component in the preferred embodiment of the present invention includes steps S10 to S80.

[0043] Step S10, establishing a three-dimensional printing model of a high-strength aluminum alloy curved inner flow channel component.

[0044] Step S20, marking the 3D printing model according to whether the surface of the high-strength aluminum alloy curved inner flow channel component can be machined and the design accuracy of the non-machinable surface parts, so as to mark the electron beam printing part and the laser / electron beam composite printing part on the 3D printing model.

[0045] Specifically, the three-dimensional printing model is marked with regions by manual marking or automatic marking by program software.

[0046] That is, the high-strength aluminum alloy curved inner flow channel component includes surface machinable parts and surface non-machinable parts. Generally, the surface machinable parts do not have high requirements on the dimensional accuracy of the printed parts, and can be assisted by subsequent machining in the first stage to achieve the design indicators. Some of the surface non-machinable parts have high design accuracy requirements, while some have low design accuracy. Therefore, by executing step S20, the parts on the three-dimensional printing model corresponding to the parts with high design accuracy requirements of the high-strength aluminum alloy curved inner flow channel component are marked as laser printed parts, and the parts on the three-dimensional printing model corresponding to the parts with low design accuracy requirements in the high-strength aluminum alloy curved inner flow channel component are marked as laser / electron beam composite printed parts.

[0047] Step S30, evacuating the working chamber of the electron beam / laser powder bed composite melting forming equipment, filling it with inert protective gas, and evacuating it for a preset number of times in sequence, wherein the preset number of times can be 1 time, or multiple times greater than 1.

[0048] Specifically, the vacuum system of the electron beam / laser powder bed composite fusion forming equipment is used to evacuate the working chamber.

[0049] Step S40, starting the powder spreading system of the electron beam / laser powder bed composite melting forming equipment to spread the high-strength aluminum alloy powder flat.

[0050] Step S50, starting the electron beam generating system of the electron beam / laser powder bed composite melting forming equipment to preheat the powder bed after powder spreading to a preset temperature.

[0051] In this way, by executing step S50, the high-strength aluminum alloy powder in the powder bed is fully preheated to reduce the probability of powder flying during subsequent printing, improve the yield of subsequent laser and electron beam printing, and eliminate residual thermal stress and cracks when executing step S50 subsequently, thereby improving the printing quality and further improving the mechanical strength of the high-strength aluminum alloy curved inner flow channel components.

[0052] Specifically, the preset temperature is ≤500° C. In practical applications, the specific temperature is adjusted according to the composition of the high-strength aluminum alloy.

[0053] Step S60, start the laser optical path system of the electron beam / laser powder bed composite melting forming equipment, use the electron beam generation system to perform layered printing according to the electron beam printing part, and use the electron beam generation system and the laser pipeline system to perform layered printing according to the laser / electron beam composite printing part to obtain an integrated precision manufacturing component. Specifically, when executing step S50, the pressure in the working chamber is less than 8×10 -3 Pa.

[0054] That is, an electron beam generating system is used to print the portion of the high-strength aluminum alloy curved inner flow channel component corresponding to the electron beam printed portion, and a laser optical path system and an electron beam generating system are used to print the portion of the high-strength aluminum alloy curved inner flow channel component corresponding to the laser / electron beam composite printed portion, and the electron beam generating system and the laser pipeline system work simultaneously.

[0055] Step S70, cooling the integrated precision-manufactured component to room temperature in the working chamber with the furnace. That is, turning off the electron beam / laser powder bed composite melting forming equipment, and cooling the integrated precision-manufactured component to room temperature in the vacuum environment in the working chamber.

[0056] Step S80, filling the working chamber with inert protective gas until the air pressure in the working chamber reaches the same as the external atmospheric pressure.

[0057] Step S90, opening the door of the working chamber and taking out the cooled integrated precision-manufactured component.

[0058] Before opening the working chamber, an inert protective gas is filled into the working chamber to facilitate the opening of the working chamber and to prevent the surface oxidation of the integrated precision-manufactured components due to sudden contact with the outside air after being taken out of the working chamber, so as to ensure that the high-strength aluminum alloy curved inner flow channel components have higher mechanical strength.

[0059] By executing steps S10 to S60, the parts with high dimensional accuracy requirements on the high-strength aluminum alloy curved inner flow channel component are obtained by laser and electron beam composite printing, and other parts with high mechanical strength and high manufacturing efficiency on the high-strength aluminum alloy curved inner flow channel component are obtained by electron beam printing. Therefore, the above-mentioned integrated precision additive manufacturing method of the high-strength aluminum alloy curved inner flow channel component combines electron beam printing and laser printing to obtain a high-strength alloy curved inner flow channel component with high dimensional accuracy and excellent mechanical properties.

[0060] By executing step S30, the air in the working chamber is exhausted by performing the steps of vacuuming, flushing inert protective gas, and vacuuming a preset number of times, thereby ensuring an excellent vacuum environment in the working chamber during the printing process and further improving the mechanical properties of the high-strength aluminum alloy curved inner flow channel component.

[0061] By executing step S70, the step of cooling the integrated precision-manufactured component to room temperature in a vacuum environment in a working chamber improves printing safety while reducing the probability of surface oxidation of the integrated precision-manufactured component during the cooling process, thereby further ensuring product dimensional accuracy.

[0062] Practice has proved that the high-strength aluminum alloy curved inner flow channel component obtained by the above-mentioned integrated precision additive manufacturing method of the high-strength aluminum alloy curved inner flow channel component has a tensile strength of ≥420MPa, a fracture elongation of ≥8%, and a dimensional accuracy better than ±0.2mm. Compared with the traditional "profile + machining" process, the formability of the curved inner flow channel structure is better.

[0063] Therefore, the use of the above-mentioned integrated precision additive manufacturing method of high-strength aluminum alloy curved inner flow channel components can obtain high-strength aluminum alloy curved inner flow channel components that have both high dimensional accuracy and high mechanical strength, so as to meet the dimensional accuracy requirements and mechanical strength requirements of components such as gas systems in the current aerospace, military manufacturing and other fields.

[0064] Please also read Figure 2 In some embodiments, step S50 includes steps S51 to S53.

[0065] Step S51, marking the machinable portion of the surface corresponding to the high-strength aluminum alloy curved inner flow channel component on the three-dimensional printing model as the electron beam printing portion.

[0066] Step S52, marking the portion of the non-machinable portion of the surface of the high-strength aluminum alloy curved inner flow channel component on the three-dimensional printing model whose dimensional accuracy absolute value is greater than the preset accuracy absolute value as the electron beam printing portion.

[0067] Step S53, marking the portion of the non-machinable portion of the surface of the high-strength aluminum alloy curved inner flow channel component on the three-dimensional printing model whose absolute value of dimensional accuracy is less than or equal to the preset absolute value of accuracy as a laser / electron beam composite printing portion.

[0068] For high-strength aluminum alloy curved inner flow channel components, the dimensional accuracy of the surface machinable part is not required to be high. Therefore, when marking the area of ​​the 3D printing model, the part of the 3D printing model corresponding to the surface machinable part is marked as the electron beam printing part to improve the printing efficiency of this part and the mechanical strength of this part after molding.

[0069] For the non-machinable surface parts of the high-strength aluminum alloy curved inner flow channel components, according to the use requirements and structural characteristics, there will inevitably be some parts whose absolute values ​​of dimensional accuracy will be greater than the preset absolute value of accuracy, and the rest will be less than or equal to the preset absolute value of accuracy. Therefore, the parts on the 3D printing model whose absolute values ​​of dimensional accuracy are greater than the preset absolute value of accuracy are marked as electron beam printed parts to improve the printing efficiency of this part and the mechanical strength of this part after molding, and the parts on the 3D printing model whose absolute values ​​of dimensional accuracy are less than or equal to the preset absolute value of accuracy are marked as laser / electron beam composite printed parts to improve the dimensional accuracy and mechanical strength of this part after molding while improving the printing efficiency of this part.

[0070] Further, in some embodiments, the laser / electron beam composite processing portion includes a laser printing layer and an electron beam printing layer.

[0071] The area on the non-machinable part of the surface of the high-strength aluminum alloy curved inner flow channel component on the three-dimensional printing model where the absolute value of the dimensional accuracy is less than or equal to the absolute value of the preset accuracy, and the area where the depth of the non-machinable surface extending toward the core is less than the preset depth value is marked as a laser printing layer.

[0072] The areas on the non-machinable parts of the surface of the high-strength aluminum alloy curved inner flow channel component on the three-dimensional printing model where the absolute value of the dimensional accuracy is less than or equal to the absolute value of the preset accuracy and the areas where the depth of the non-machinable surface extending toward the core is greater than or equal to the preset depth value are marked as electron beam printing layers.

[0073] Therefore, the laser / electron beam printed part is composed of a laser printed layer and an electron beam printed layer located inside the laser printed layer. The outer layer of this part after printing has high dimensional accuracy, the inner layer of this part has high mechanical strength, and the printing efficiency of the inner layer can be improved. In this way, it can be ensured that this part of the structure formed by stacking printing according to the laser / electron beam composite printing part has both high dimensional accuracy and high mechanical strength, and the printing efficiency is also high.

[0074] In some embodiments, the preset absolute value of the precision is ≤ 0.2 mm. That is, the surface dimension precision of the high-strength aluminum alloy curved inner flow channel component obtained by laser printing is required to be better than 0.2 mm.

[0075] Furthermore, in some embodiments, in the laser / electron beam composite printing part, the preset depth is 0.3 mm to the thickness value of the corresponding part. It should be noted that the thickness value of the corresponding part refers to the structural design dimensions such as the wall thickness of the concerned part in the non-machinable part of the upper surface of the high-strength aluminum alloy curved inner flow channel component in the depth direction perpendicular to the non-machinable surface.

[0076] The preset depth is designed to be between 0.3 mm and the thickness value of the corresponding part to ensure that the rough surface of the electron beam forming part can be completely covered by the laser forming part, thereby ensuring a forming surface with high dimensional accuracy.

[0077] Of course, the larger the value of the preset depth is, the lower the manufacturing efficiency of the high-strength aluminum alloy curved inner flow channel component is. Therefore, when selecting the preset depth, it is necessary to comprehensively consider the structural characteristics of this part of the high-strength aluminum alloy curved inner flow channel component.

[0078] In some embodiments, after step S90, the method further includes: flushing residual powder and slag in the inner flow channel of the integrated precision manufacturing component with a high-pressure fluid until there is no residual powder and slag in the inner flow channel. The high-pressure fluid may be high-pressure gas, high-pressure water, etc.

[0079] In this way, by executing the above-mentioned step of flushing the inner flow channel of the one-piece precision manufactured component, the powder, slag, etc. remaining in the inner flow channel of the one-piece precision manufactured component during the processing are removed, thereby further ensuring that the high-strength aluminum alloy curved inner flow channel component has a high dimensional accuracy.

[0080] Please also read Figure 3 In some embodiments, step S90 includes step S91 and step S92.

[0081] Step S91, open the door of the working chamber and take out the forming cylinder.

[0082] Step S92, cleaning the integrated precision-manufactured component from the powder bed in the forming cylinder.

[0083] By executing step S91 and step S92, the cooled integrated precision-manufactured component is taken out from the working chamber in two steps, thereby improving the convenience of taking out the integrated precision-manufactured component.

[0084] In some embodiments, the preset number of times is ≥ 2. Step S30 is repeated at least twice to ensure that the air in the working chamber is completely exhausted, to prevent the surface of the integrated precision-manufactured component from being oxidized when step S60 is subsequently performed, and to further improve the mechanical strength of the high-strength aluminum alloy curved inner flow channel component.

[0085] In order to further improve the mechanical strength of the high-strength aluminum alloy curved inner flow channel component, in some embodiments, when executing step S60, the printing layer thickness is 40 μm to 100 μm.

[0086] In some embodiments, when executing step S60, the laser scanning speed is 600 mm / s to 1400 mm / s, and the electron beam scanning speed is 750 mm / s to 1250 mm / s. Thus, when executing step S60, the laser printing speed and the electron beam printing speed are similar to ensure the perfect coordination of laser printing and electron beam printing, and ensure the excellent fusion effect between the laser printing part and the electron beam printing part on the molded part, which is conducive to further improving the mechanical strength of the high-strength aluminum alloy curved inner flow channel component.

[0087] In some embodiments, the particle size of the high-strength aluminum alloy powder is between 40 μm and 150 μm, so that the sintering quality of the high-strength aluminum alloy powder during step S60 can be ensured to be high, thereby obtaining a high-strength aluminum alloy curved inner flow channel component with higher mechanical strength.

[0088] In order to more intuitively understand the beneficial effects of the above-mentioned integrated precision reinforcement manufacturing method of the high-strength aluminum alloy curved inner flow channel component, it is verified through the following embodiments.

[0089] Examples 1 to 4 are verifications of the present invention in the material system. The raw materials used in Examples 1 and 2 are Al-Cu matrix aluminum alloy powders, and the raw materials used in Examples 3 to 5 are Al-Zn matrix aluminum alloy powders, and their chemical compositions are shown in Table 1 below.

[0090] Table 1 Chemical composition of the examples (unit: wt%)

[0091]

[0092] The manufacturing steps of Examples 1-4 are consistent, except that the printing layer thickness of Examples 1 and 3 is 60 μm, the laser scanning speed is 1200 mm / s, the scanning speed of the electron beam is 1000 mm / s, the powder bed preheating temperature is 400°C, and the powder D50 particle size is 75 μm; the printing layer thickness of Examples 2 and 4 is 80 μm, the laser scanning speed is 1000 mm / s, the scanning speed of the electron beam is 850 mm / s, the powder bed preheating temperature is 400°C, and the powder D50 particle size is 105 μm.

[0093] The tensile properties of Examples 1 to 4 were tested in accordance with the requirements of GB / T 228.1, and the dimensional accuracy of Examples 1 to 4 was measured using a height gauge. All test results are shown in Table 2.

[0094] Table 2 Performance test results of Examples 1-4

[0095]

[0096] Obviously, the integrated precision additive method for the high-strength aluminum alloy curved inner flow channel components proposed in the present invention is easy to operate, has high molding efficiency, low raw material cost, good adaptability to structure and size, and excellent molded part performance and precision. It can be used for the molding of inner flow channel components used in high-end equipment power systems.

[0097] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0098] The above-mentioned embodiments only express several implementation methods of the present invention, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the invention patent. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. An integrated precision additive manufacturing method for a high-strength aluminum alloy curved inner flow channel component, characterized in that: Includes steps: Establish a 3D printing model of a high-strength aluminum alloy curved inner flow channel component; Marking the three-dimensional printed model according to whether the surface of the high-strength aluminum alloy curved inner flow channel component can be machined and the design accuracy of the non-machinable portion of the surface, so as to mark the electron beam printed part and the laser / electron beam composite printed part on the three-dimensional printed model; Specifically include Step: marking the machinable portion of the surface of the three-dimensional printing model corresponding to the high-strength aluminum alloy curved inner flow channel component as the electron beam printing portion; Marking a portion of the non-machinable portion of the surface of the high-strength aluminum alloy curved inner flow channel component on the three-dimensional printing model, where the absolute value of the dimensional accuracy is greater than the absolute value of the preset accuracy, as the electron beam printed portion; Marking a portion of the non-machinable portion of the surface of the high-strength aluminum alloy curved inner flow channel component on the three-dimensional printing model, where the absolute value of the dimensional accuracy is less than or equal to the absolute value of the preset accuracy, as a laser / electron beam composite printing portion; The working chamber of the electron beam / laser powder bed composite melting forming equipment is sequentially evacuated, filled with inert protective gas, and evacuated for a preset number of times; Start the powder spreading system of the electron beam / laser powder bed composite melting forming equipment to spread the high-strength aluminum alloy powder flat; Starting the electron beam generating system of the electron beam / laser powder bed composite melting forming equipment to preheat the powder bed after powder spreading to a preset temperature; Start the laser optical path system of the electron beam / laser powder bed composite fusion forming device, use the electron beam generation system to perform layered printing according to the electron beam printing part, and use the electron beam generation system and the laser pipeline system to perform layered printing according to the laser / electron beam composite printing part to obtain an integrated precision manufacturing component; Cooling the integrated precision-manufactured component to room temperature in the working chamber along with the furnace; Filling the working chamber with inert protective gas until the air pressure in the working chamber reaches the external atmospheric pressure; Opening the door of the working chamber and taking out the cooled integrated precision-manufactured component; The laser / electron beam composite processing part includes a laser printing layer and an electron beam printing layer; the area on the three-dimensional printing model corresponding to the non-machinable part of the surface of the high-strength aluminum alloy curved inner flow channel component where the absolute value of the dimensional accuracy is less than or equal to the absolute value of the preset accuracy, and the area where the non-machinable surface extends to the core at a depth less than a preset depth value is marked as the laser printing layer; The portion on the three-dimensional printing model corresponding to the non-machinable portion of the surface of the high-strength aluminum alloy curved inner flow channel component where the absolute value of the dimensional accuracy is less than or equal to the absolute value of the preset accuracy, and the area where the non-machinable surface extends toward the core to a depth greater than or equal to the preset depth value is marked as the electron beam printing layer.

2. The integrated precision additive manufacturing method of a high-strength aluminum alloy curved inner flow channel component according to claim 1, characterized in that: In the laser / electron beam composite printing part, the preset depth is 0.3 mm to the thickness value of the corresponding part.

3. The integrated precision additive manufacturing method of a high-strength aluminum alloy curved inner flow channel component according to claim 1, characterized in that: The absolute value of the preset accuracy is ≤0.2mm.

4. The integrated precision additive manufacturing method of a high-strength aluminum alloy curved inner flow channel component according to claim 1, characterized in that: After the step of opening the door of the working chamber and taking out the cooled formed product, the process further includes: The inner flow channel of the formed part is flushed with high-pressure fluid until no powder residue or slag is left in the inner flow channel.

5. The integrated precision additive manufacturing method of a high-strength aluminum alloy curved inner flow channel component according to claim 1, characterized in that: The preset temperature is ≤500°C.

6. The integrated precision additive manufacturing method of a high-strength aluminum alloy curved inner flow channel component according to claim 1, characterized in that: The preset number of times is ≥2 times.

7. The integrated precision additive manufacturing method of a high-strength aluminum alloy curved inner flow channel component according to claim 1, characterized in that: When performing the layer-by-layer printing step, the pressure in the working chamber is less than 8×10 -3 Pa.

8. The integrated precision additive manufacturing method of a high-strength aluminum alloy curved inner flow channel component according to claim 1, characterized in that: When performing the printing step, the printing layer thickness is 40 μm to 100 μm.

9. The integrated precision additive manufacturing method of a high-strength aluminum alloy curved inner flow channel component according to claim 1, characterized in that: When executing the printing step, the laser scanning speed is 600 mm / s to 1400 mm / s, and the electron beam scanning speed is 750 mm / s to 1250 mm / s.

10. The integrated precision additive manufacturing method of a high-strength aluminum alloy curved inner flow channel component according to claim 1, characterized in that: The particle size of the high-strength aluminum alloy powder is 40 μm to 150 μm.

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