A method of additive manufacturing process detection and aluminum alloy part

Abstract

The application relates to an additive manufacturing forming process detection method and an aluminum alloy part, and belongs to the technical field of additive manufacturing. The detection method is to plan a part feature structure and form a slice, which is divided into a scanning entity and a scanning contour; powder bed melting printing is carried out, radioactive element ions are injected according to a scanning path of the scanning contour, and the injection frequency is controlled; radioactive element capturing and judgment are carried out; if the radioactive elements are continuously distributed, the printing is continued; and if the radioactive elements are discontinuously or irregularly distributed, the printing is paused. The detection method provided by the application can detect the printed area in real time and accurately, and a designer can make accurate judgment.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of additive manufacturing technology, in particular to an additive manufacturing forming process detection method and an aluminum alloy part. BACKGROUND

[0002] In the additive manufacturing forming process, cracking, bulging, warping and other phenomena often occur in the part product, especially in the powder bed fusion technology. Due to the slow heat dissipation of the powder bed, stress accumulation and / or heat accumulation exist in the part, resulting in cracking of the part in the powder buried area (the area where printing is completed).

[0003] At present, the monitoring of cracking only has the methods of molten pool monitoring and equipment equipped with cameras to take pictures. The above-mentioned methods can only monitor in real time, i.e. monitoring the current printing layer. Due to the gradual burying of the powder material, it is impossible to determine whether cracking occurs in the area where printing is completed and which positions cracking occurs.

[0004] This problem causes great trouble to the production process and affects the judgment of the designers. In addition, it also causes great economic loss due to the failure to assess the cracking risk and stop in time. Therefore, it is urgent to detect the area where printing is completed in real time. SUMMARY

[0005] In view of the above analysis, the present application aims to provide an additive manufacturing forming process detection method and an aluminum alloy part to solve the problem that the existing detection method cannot detect the area where printing is completed in real time.

[0006] In one aspect, the present application provides an additive manufacturing forming process detection method, comprising the following steps:

[0007] S1: planning and forming slices for the part feature structure, and dividing into scanning entities and scanning contours;

[0008] S2: powder bed fusion printing, and injecting radioactive element ions according to the scanning path of the scanning contour, and controlling the injection frequency thereof;

[0009] S3: capturing and judging the radioactive elements. If the radioactive elements are continuously distributed, the printing is continued. If the radioactive elements are discontinuously or irregularly distributed, the printing is paused.

[0010] Further, the radioactive element is europium.

[0011] Further, the injection frequency of the radioactive element ions is 10-100 layers injected once.

[0012] Further, the injection amount of the radioactive element ions is 5x10 15 -5x10 16 ions / cm2 .

[0013] Further, the radioactive element ion implantation parameters are: an acceleration voltage of 80-150kV, a beam intensity of 15-30muA, and an implantation angle of 45-90 degrees.

[0014] Further, the part is an aluminum alloy, and the chemical composition includes, in terms of mass percentage: Si: 9-10%, Mg: 0.2-0.5%, Fe: <=0.5%, Cu: <=0.05%; and the balance is Al.

[0015] Further, the powder bed fusion is a laser selective melting process.

[0016] Further, in the laser selective melting process, the scanning speed is 1100-1500mm / s, the laser power is 350-500w, the scanning interval is 0.08-0.15mm, and the powder layer thickness is 0.03-0.06mm.

[0017] Further, the implantation width of the radioactive element ions is 0.1-0.5mm.

[0018] In another aspect, the application provides an aluminum alloy part formed by additive manufacturing, wherein the additive manufacturing uses the detection method of the application, and the aluminum alloy part contains a radioactive element ion implantation layer.

[0019] Compared with the prior art, the application can achieve at least one of the following beneficial effects:

[0020] 1. The application divides the part to be printed into scanning entities and scanning contours, implants radioactive elements when printing the scanning contours, and controls the implantation frequency; when a crack appears during printing, the radioactive elements are discontinuous, and printing needs to be stopped; when there is no crack, the radioactive elements are continuous, and printing does not need to be stopped. The detection method provided by the application can detect the printed area in real time and accurately, and the designer can make accurate judgments.

[0021] 2. In the application, the radioactive element is europium, which can penetrate the aluminum alloy and clearly observe the distribution, and does not affect or ensure the performance of the aluminum alloy part; in addition, the radioactive element implantation amount, implantation frequency, and implantation parameters need to be strictly controlled to ensure the strength, implantation depth, and distribution uniformity, so that the designer can make accurate judgments.

[0022] The technical solutions in the present application can be combined with each other to realize more preferred combination solutions. Other features and advantages of the present application will be described in the following description, and some advantages will become apparent from the description, or will be understood by those skilled in the art through implementation of the present application. The objects and other advantages of the present application can be realized and obtained through the contents particularly pointed out in the description and the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0023] The accompanying drawings are included to provide a further understanding of the present application, and are incorporated herein and constitute a part of the detailed description. The drawings illustrate embodiments of the present application and, together with the description, serve to explain the principles of the present application. In the drawings:

[0024] Figure 1 A part cracking map during a printing process;

[0025] Figure 2 A scanning solid route map during a printing process;

[0026] Figure 3 A scanning contour route map during a printing process;

[0027] Figure 4 A detection result schematic diagram;

[0028] In the drawings, 1, a printing layer; 2, an ion implantation layer. DETAILED DESCRIPTION

[0029] The preferred embodiments of the present application will be described in detail below with reference to the drawings, wherein the drawings constitute a part of the present application and serve to explain the principles of the embodiments of the present application, but are not used to limit the scope of the present application.

[0030] In an additive manufacturing forming process, due to stress accumulation problems or heat accumulation problems, etc., cracking, bulging, warping, etc. of a part will occur (refer to Figure 1 At present, the monitoring of cracking only has a molten pool monitoring method, a camera shooting method, etc. The above methods can only be used for real-time monitoring, that is, the current printing layer is monitored.

[0031] However, in the field of powder bed fusion technology, there is a gradual powder laying process, and the powder in the unprinted area will cover the printed area, so the existing detection method cannot detect the cracking problem of the printed area, and thus cannot make accurate judgment.

[0032] Therefore, the present application provides an additive manufacturing forming process detection method, comprising the following steps:

[0033] S1: planning a part feature structure and forming a slice, and dividing into a scanning solid and a scanning contour;

[0034] S2: powder bed fusion printing, and injecting radioactive element ions according to the scanning path of the scanning contour, and controlling the injection frequency thereof;

[0035] S3: capturing and judging the radioactive element, if the radioactive element is continuously distributed, continuing printing; if the radioactive element is discontinuously or irregularly distributed, suspending printing.

[0036] Compared with the prior art, the additive manufacturing process detection method provided by the application is to add radioactive elements in printing, and finally capture the radioactive elements and judge whether the radioactive elements are continuously distributed.

[0037] It should be noted that, in the additive manufacturing process and the detection process, the scanning path is planned and slices are formed according to the structural characteristics of the part; then printing is performed, layer-by-layer powder laying printing is performed, the scanning entity is printed first, then the scanning contour is printed, and radioactive element ions are injected according to the scanning path of the scanning contour. When injecting the radioactive element ions, they are not injected layer by layer, but need to be injected at different intervals; finally, the radioactive element ions are captured or detected, and when there is no crack and other problems, the radioactive elements are continuously distributed, but when there are cracks and other problems, the radioactive elements are discontinuously distributed.

[0038] The detection method provided by the application can be used for real-time detection during printing, and when the intermittent state occurs, the printing is immediately suspended, and the designer judges whether the printing can be performed or adjusts the corresponding printing parameters. The detection method provided by the application can also be used for detection after printing is completed, and some parts crack during the cooling process, some on the surface and some inside, and the application can still observe the distribution of the radioactive element ions to judge the crack condition.

[0039] Specifically, the radioactive element is europium.

[0040] It should be noted that, in the application, the radioactive element used is europium, on the one hand, europium can penetrate aluminum alloy, which is convenient for capturing or observing the distribution thereof; on the other hand, the europium element not only does not reduce the performance of the aluminum alloy, but also improves the performance of the aluminum alloy.

[0041] After injecting europium ions into the aluminum alloy, the europium ions will interact with aluminum and other alloy elements to form some new compound phases or solid solution phases, such as Mg2Eu and EuSi2. The formation of these new phases can change the organizational structure of the surface of the aluminum alloy, such as forming fine and dispersed strengthening phases, thereby affecting the performance of the aluminum alloy. In addition, it is helpful to refine the grain size of the surface of the aluminum alloy, so that the grain size is reduced. Grain refinement can increase the grain boundary area, hinder dislocation movement, thereby improving the strength and hardness of the surface of the aluminum alloy, and also possibly improving the toughness and fatigue resistance of the aluminum alloy, further reducing the risk of cracking.

[0042] Specifically, the injection frequency of the radioactive element ions is 10 layers-100 layers once.

[0043] It should be noted that the injection of radioactive element ions is not layer by layer, but has a certain interval, that is, the injection frequency. In the present application, the injection frequency is controlled to be once every 10 layers to 100 layers, that is, the aluminum alloy is injected once every 10 layers to 100 layers. When the injection frequency is too fast, that is, less than 10 layers, the distance between the injected ion layers is close, and there is mutual interference, so it is difficult to determine whether a crack occurs; when the injection frequency is too slow, that is, more than 100 layers, the distance between the injected ion layers is far, and it is difficult to determine whether the aluminum alloy layer between the ion layers is cracked.

[0044] Preferably, the injection frequency of the radioactive element ions of the present application can be 10 layers, 20 layers, 30 layers, 40 layers, 45 layers, 50 layers, 55 layers, 60 layers, 70 layers, 83 layers, 90 layers, 95 layers or 100 layers.

[0045] Preferably, the injection frequency of the radioactive element ions of the present application is 30-80 layers.

[0046] More preferably, the injection frequency of the radioactive element ions of the present application is 40-60 layers.

[0047] Specifically, the injection amount of the radioactive element ions is 5×10 15 -5×10 16 ions / cm 2 .

[0048] It should be noted that the injection amount of ions is expressed in the number of ions per square centimeter, and the size of the injection amount directly affects the concentration and distribution on the surface of the part that has been printed, and further determines the display intensity. When the injection amount is lower, that is, lower than 5×10 15 ions / cm 2 , the display intensity is weak or cannot form a continuous distribution state, thereby causing the designer to misjudge; if the injection amount is higher than 5×10 16 ions / cm 2 , it has little effect on the detection result, but it will cause waste.

[0049] Specifically, the radioactive element ion injection parameters are: acceleration voltage 80-150 kV, beam intensity 15-30 μA, and injection angle 45°-90°.

[0050] It should be noted that the present application uses the existing ion implanter to stably implant radioactive element europium on the surface of aluminum alloy (to print the completed part), and needs to control the acceleration voltage, beam intensity and implantation angle.

[0051] The size of the acceleration voltage determines the implantation depth of europium ions, when the acceleration voltage is less than 80kV, the implantation depth is shallow, on the contrary, when the acceleration voltage is greater than 150kV, the implantation depth is deep. In the present application, the shallow or deep implantation depth is not conducive to the accurate judgment of the design of the human, so the acceleration voltage can be 80kV, 85kV, 90kV, 95kV, 100kV, 110kV, 120kV, 130kV, 1350kV, 140kV or 150kV.

[0052] Preferably, the acceleration voltage is 100-120kV.

[0053] The beam intensity determines the implantation efficiency of ions, and needs to be controlled in 15-30μA, the greater the beam intensity, the more the number of europium ions implanted into the surface of the printed area per unit time, the higher the implantation efficiency, but at the same time, it may also cause the surface temperature of the part to rise too fast, produce thermal effect, affect the quality and performance of the implanted layer. On the contrary, the smaller the beam intensity, the fewer the number of europium ions implanted into the surface of the printed area per unit time, the lower the implantation efficiency.

[0054] Preferably, the beam intensity can be 15μA, 18μA, 20μA, 25μA, 28μA or 30μA.

[0055] More preferably, the beam intensity is 20-25μA.

[0056] The control of the implantation angle can ensure the uniformity of ion implantation and the consistency of depth distribution, the present application controls the implantation angle to be 45-90°. Selecting the vertical implantation to the surface of the printed completed area can make the ion vertical incidence, ensure the uniformity of implantation and the consistency of depth distribution. But in some special cases, such as the optimization of the performance of a specific direction, a certain angle of inclined implantation can also be used, but the angle generally should not be too large, in order to avoid the reflection and scattering of ions on the sample surface, affect the implantation effect.

[0057] Preferably, the implantation angle is 60°-90°.

[0058] Specifically, the part is aluminum alloy, and the chemical composition includes, according to the mass percentage: Si: 9-10%, Mg: 0.2-0.5%, Fe: ≤0.5%, Cu: ≤0.05%; the balance is Al.

[0059] It should be noted that the material of the part in the application is aluminum alloy, through the mutual cooperation between elements, on the one hand, the strength of the part is ensured, and cracking is reduced, on the other hand, the penetration of the radioactive element europium is ensured. Because the profile parameters are ion implanted, the scanning range of the profile parameters is only about 0.1mm, which has a small impact on the product. Moreover, a small amount of europium element forms Al3Eu second phase with Al, which plays a strengthening role after heat treatment, enhancing the surface strength of the part.

[0060] Specifically, the powder bed fusion is a laser selective melting process.

[0061] Specifically, in the laser selective melting process, the scanning speed is 1100-1500mm / s, the laser power is 350-500w, the scanning interval is 0.08-0.15mm, and the powder layer thickness is 0.03-0.06mm.

[0062] Preferably, the scanning speed is 1200mm / s, the laser power is 400w, the scanning interval is 0.1mm, and the powder layer thickness is 0.05mm.

[0063] Specifically, the injection width of the radioactive element ion is 0.1-0.5mm.

[0064] The application provides an aluminum alloy part, which is formed by additive manufacturing, the detection method is used in the additive manufacturing, and the aluminum alloy part contains a radioactive element ion implantation layer. The part can be designed according to actual needs, the material of the part is aluminum alloy, and Mg2Eu or EuSi2 phase is formed in the aluminum alloy.

[0065] In order to more clearly describe the application, the following examples and comparative examples are further described.

[0066] Example 1

[0067] The detection in the printing process specifically includes the following steps:

[0068] S1: planning and forming slices for the part feature structure, and dividing into scanning entities and scanning contours (referring to Figure 2 and Figure 3 );

[0069] S2: powder bed fusion printing, and injecting radioactive element ions according to the scanning path of the scanning contour to control the injection frequency thereof;

[0070] The material of the part is aluminum alloy, and the chemical composition includes, in terms of mass percentage, Si: 9.5%, Mg: 0.3%, Fe: 0.2%, Cu: 0.05%; and the balance is Al.

[0071] The powder bed fusion printing adopts a laser selective melting process, the scanning speed is 1200 mm / s, the laser power is 400 w, the scanning interval is 0.1 mm, and the powder layer thickness is 0.05 mm.

[0072] The radioactive element ion europium is injected, and the injection amount of the radioactive element ion is 5x1015ions / cm 2 The acceleration voltage is 100 kV, the beam current intensity is 20 mu A, the injection angle is 90 degrees (perpendicular to the printed area), and the injection frequency is 10 layers per injection; and the injection width of the radioactive element ion is 0.1 mm.

[0073] S3: Capture and judgment of the radioactive element, if the radioactive element is continuously distributed, continue printing; if the radioactive element is discontinuous or irregularly distributed, pause printing.

[0074] Example 2

[0075] The detection of the printed final product specifically includes the following steps:

[0076] S1: Plan the feature structure of the part and form slices; divide into scanning entities and scanning contours;

[0077] S2: Powder bed fusion printing, and inject radioactive element ions according to the scanning path of the scanning contour to control the injection frequency;

[0078] The material of the part is aluminum alloy, and the chemical composition includes, in terms of mass percentage: Si: 10.0%, Mg: 0.5%, Fe: 0.25%, Cu: 0.01%; and the balance is Al.

[0079] The powder bed fusion printing adopts a laser selective melting process, the scanning speed is 1100 mm / s, the laser power is 350 w, the scanning interval is 0.08 mm, and the powder layer thickness is 0.03 mm;

[0080] The radioactive element ion europium is injected, and the injection amount of the radioactive element ion is 5x10 16 ions / cm 2 The acceleration voltage is 150 kV, the beam current intensity is 30 mu A, the injection angle is 80 degrees, and the injection frequency is 50 layers per injection.

[0081] S3: Capture and judgment of the radioactive element, if the radioactive element is continuously distributed, there is no crack; if the radioactive element is discontinuous or irregularly distributed, there is a crack.

[0082] Example 3

[0083] The detection during the printing process specifically includes the following steps:

[0084] S1: planning and forming slices for part features; dividing into scanning entities and scanning contours;

[0085] S2: powder bed fusion printing, and injecting radioactive element ions according to the scanning path of the scanning contour to control the injection frequency thereof;

[0086] The part is made of aluminum alloy, and the chemical components include, in percentage by mass: Si: 10.0%, Mg: 0.5%, Fe: 0.25%, Cu: 0.01%; and the balance is Al.

[0087] The powder bed fusion printing adopts a laser selective melting process, the scanning speed is 1500 mm / s, the laser power is 500 w, the scanning interval is 0.15 mm, and the powder layer thickness is 0.06 mm.

[0088] The radioactive element ions are europium ions, and the injection amount of the radioactive element ions is 5*10 16 ions / cm 2 The acceleration voltage is 80 kV, the beam intensity is 15 mu A, the injection angle is 80 degrees, and the injection frequency is 90 layers of injection once.

[0089] S3: capturing and judging the radioactive elements, if the radioactive elements are continuously distributed, there is no crack; if the radioactive elements are discontinuously or irregularly distributed, there is a crack.

[0090] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, any person skilled in the art can easily think of changes or replacements within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A method of detecting an additive manufacturing process forming process, characterized in that, The method comprises the following steps: S1: planning and slicing the part feature structure, dividing into scanning entities and scanning contours; S2: powder bed fusion printing, and injecting radioactive element ions according to the scanning path of the scanning contour, and controlling the injection frequency, the radioactive element being europium; S3: capturing and judging the radioactive element, if the radioactive element is continuously distributed, continue printing; if the radioactive element is discontinuously or irregularly distributed, pause printing.

2. The method of claim 1, wherein: The injection frequency of the radioactive element ions is 10-100 layers per injection.

3. The method of claim 1, wherein: The amount of the radioactive element ions injected is 5 x 1010 15 - 5 x 1010 16 ions / cm2.

4. The method of claim 1, wherein: The radioactive element ion injection parameters are: an acceleration voltage of 80-150 kV, a beam current intensity of 15-30 μA, and an injection angle of 45-90°.

5. The method of claim 1, wherein: The part is an aluminum alloy, and the chemical composition includes, in terms of mass percentage: Si: 9-10%, Mg: 0.2-0.5%, Fe: ≤0.5%, Cu: ≤0.05%; and the balance is Al.

6. The method of claim 1, wherein: The powder bed fusion is a laser selective melting process.

7. The method of claim 6, wherein: In the laser selective melting process, the scanning speed is 1100-1500 mm / s, the laser power is 350-500 w, the scanning interval is 0.08-0.15 mm, and the powder layer thickness is 0.03-0.06 mm.

8. The method of claim 1, wherein: The injection width of the radioactive element ions is 0.1-0.5 mm.

9. An aluminum alloy part characterized by, The aluminum alloy part contains a radioactive element ion injection layer by additive manufacturing, and the detection method of any one of claims 1-8 is used in the additive manufacturing.

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