Surface Exposure Additive Manufacturing Method of a Conforming Stress Sensor for Aero Complex Components

Abstract

The present invention discloses a surface exposure additive manufacturing method for a conformable stress sensor of an aviation complex component, belonging to the field of flexible sensor manufacturing. The sensor has a two-layer structure, including a flexible installation layer and a stress detection layer. The flexible installation layer is formed by DLP printing using flexible resin without adding any conductive fillers. Its model is derived from an aviation complex component. According to the aviation complex model, a model with the same contour curve as the model is established through 3D scanning to meet the requirement of conforming to the aviation complex structure. The stress detection layer uses multiple materials and is formed by DLP printing by adding various materials such as conductive fillers and diluents to the flexible resin to meet the stress detection of the aviation complex component; leads are added to the stress detection layer and are led out from both ends of the stress detection layer covered with cured conductive paste and connected to a resistance measuring device. The present invention can meet the perfect fitting of the surface of the aviation complex component and can also detect stress.

Description

Technical Field

[0001] The present invention relates to the field of flexible sensor manufacturing, and particularly to a surface exposure additive manufacturing method for a conformable stress sensor of an aviation complex component. Background Art

[0002] With the continuous progress of science and technology and the continuous development of China's aviation level, the demand for aviation complex components is increasing, and the requirements for the surface accuracy of complex structures and the pressure that can be borne are becoming more and more stringent. Therefore, the aviation industry has a great demand for sensors that can accurately measure stress. However, due to the usually complex structures of aviation structures, such as aviation engine blades and engine walls, traditional sensors cannot be perfectly attached to the surfaces of these complex structures, so the stress received by the structures cannot be accurately measured. Summary of the Invention

[0003] In view of the above deficiencies of the prior art, the present invention provides a surface exposure additive manufacturing method for a conformable stress sensor of an aviation complex component, which is convenient for better measuring the stress of an aviation complex structure and can perfectly conform to the aviation complex structure.

[0004] The technical solution for achieving the object of the present invention is as follows:

[0005] A surface exposure additive manufacturing method for a conformable stress sensor of an aviation complex component, the stress sensor having a two-layer structure, including a flexible mounting layer and a stress detection layer; the flexible mounting layer is made of a flexible resin without adding any conductive fillers and is formed by DLP printing. The model of the flexible mounting layer comes from an aviation complex component, and a model with the same outer contour curve as the model is established through 3D scanning, meeting the requirement of conforming to the aviation complex structure; the stress detection layer has a structure consistent with the outer contour curve of the three-dimensional model of the flexible mounting layer. A variety of materials such as conductive fillers and diluents are added to the flexible resin and formed by DLP printing to meet the detection of the stress of the aviation complex component; leads are added to the stress detection layer and led out from both ends of the stress detection layer covered with cured conductive paste and connected to a resistance measuring device; including the following steps:

[0006] Step S1: Perform 3D scanning on the aviation complex component, establish a model with the same outer contour curve as the aviation complex model through 3D scanning to meet the requirement of conforming to the aviation complex structure, and then establish a three-dimensional model of the flexible mounting layer;

[0007] Step S2: Import the three-dimensional model of the flexible mounting layer into the DLP printing device, configure the relevant parameters of DLP 3D printing as: DLP ultraviolet light source wavelength 405 nm, liquid tank ultrasonic cleaning time 30 s - 40 s, fan drying temperature 20 - 30 °C, then add flexible resin to the device and perform printing of the flexible mounting layer;

[0008] Step S3: After the flexible mounting layer is printed, sequentially replace the multi-functional platform of the printing device to the ultrasonic cleaning station and the drying station to complete the cleaning and drying of the printed parts.

[0009] Step S4: Establish a three-dimensional model of the stress detection layer through the flexible mounting layer, and then import the three-dimensional model of the stress detection layer into the DLP printing device. Configure the relevant parameters for DLP 3D printing as follows: the wavelength of the DLP ultraviolet light source is 405 nm, the ultrasonic cleaning time of the liquid tank is 30 s - 40 s, the fan drying temperature is 20 - 30 °C. Then add the configured mixed matrix and perform the printing of the stress detection layer.

[0010] Step S5: After the stress detection layer is printed, sequentially replace the multi-functional platform of the printing device to the ultrasonic cleaning station and the drying station to complete the cleaning and drying of the printed parts.

[0011] Step S6: Next, perform the lead wire operation, leading out from both ends of the strain sensor where the cured conductive paste is coated and connecting it to the resistance measuring device.

[0012] Further, the flexible mounting layer of the stress sensor is made of flexible photosensitive resin, and its thickness is between 1 mm and 2 mm.

[0013] Further, the stress detection layer of the stress sensor is prepared from a composite material. Add multi-walled carbon nanotubes as conductive fillers to the flexible photosensitive resin, add TPO photoinitiator, IBOM diluent, and BYK163 dispersant and mix them. After ultrasonic stirring for 30 min, a mixed matrix is obtained.

[0014] Further, for the stress detection layer of the stress sensor, its structure is consistent with the outer contour curve of the three-dimensional model of the flexible mounting layer, and the layer thickness increase during printing is between 2 mm and 4 mm.

[0015] Further, the resistance value of the stress sensor changes with the applied stress, and the change rate of the resistance is proportional to the magnitude of the stress.

[0016] Further, after the DLP prints the stress detection layer of the stress sensor, sequentially replace the multi-functional platform of the printing device to the ultrasonic cleaning station and the drying station to complete the cleaning and drying of the printed parts.

[0017] Further, after the DLP prints the flexible mounting layer of the stress sensor, sequentially replace the multi-functional platform of the printing device to the ultrasonic cleaning station and the drying station to complete the cleaning and drying of the printed parts.

[0018] Further, the lead wires added to the stress detection layer are copper, gold, and silver wires with a diameter ranging from 2 μm to 2 mm, and the lead wires are bonded to the cured conductive paste through nano silver paste.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] (1) The surface exposure additive manufacturing method of the conformable stress sensor for aviation complex components provided by the present invention uses 3D scanning of complex structures. The stress sensor has the same outer contour curve as the aviation complex structure and can be perfectly conformable.

[0021] (2) The surface exposure additive manufacturing method of the conformable stress sensor for aviation complex components provided by the present invention has a large stress measurement range, good performance stability, good repeatability, high sensitivity. And compared with traditional sensors, the stress sensor has a larger thickness and better durability.

[0022] (3) The surface exposure additive manufacturing method of the conformable stress sensor for aviation complex components provided by the present invention adopts a double-layer structure, can be disassembled, and has good interchangeability. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a flow chart of the present invention;

[0024] Figure 2 is a three-dimensional model diagram of a turbine blade structure;

[0025] Figure 3 is a three-dimensional model diagram of a windmill blade structure;

[0026] Figure 4 is a three-dimensional model of a conformable stress sensor for a turbine blade;

[0027] Figure 5 is a three-dimensional model of a conformable stress sensor for a windmill blade;

[0028] Figure 6 is a curve graph showing the change of the stress of the detection sensor with the speed of the complex structure; DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The following is a description of the present invention based on embodiments, but the present invention is not limited to these embodiments. In the following detailed description of the present invention, some specific details are described in detail. Those skilled in the art can fully understand the present invention without the description of these details. In order to avoid obscuring the essence of the present invention, well-known methods, processes, procedures, elements and circuits are not described in detail.

[0030] In addition, those of ordinary skill in the art should understand that the drawings provided herein are for illustrative purposes only, and the drawings are not necessarily drawn to scale.

[0031] Meanwhile, it should be understood that in the following description, a "circuit" refers to a conductive loop formed by at least one component or sub-circuit through electrical connection or electromagnetic connection. When an element or circuit is said to be "connected to" another element or when an element / circuit is said to be "connected between" two nodes, it may be directly coupled or connected to another element or there may be intermediate elements. The connection between elements can be physical, logical, or a combination thereof. In contrast, when an element is said to be "directly coupled to" or "directly connected to" another element, it means there are no intermediate elements between the two.

[0032] Unless the context clearly requires otherwise, the words such as "comprising", "including" and the like in the whole specification and claims shall be construed in an inclusive sense rather than an exclusive or exhaustive sense; that is, the meaning of "including but not limited to".

[0033] In the description of the present invention, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. In addition, in the description of the present invention, unless otherwise specified, the meaning of "a plurality of" is two or more.

[0034] In the conforming stress sensor for aviation complex components of the present invention, the flexible strain layer uses flexible photosensitive resin as the matrix and is formed by DLP printing. The stress detection layer is formed by DLP printing by adding various materials such as conductive fillers and diluents to the flexible resin.

[0035] The technical solution of the present invention will be described in detail below through specific embodiments so that those skilled in the art can better understand and implement the technical solution of the present invention, but the present invention is not limited to the scope of the examples.

[0036] Example 1

[0037] The photosensitive resin for printing the flexible mounting layer of the pressure sensor provided in this example, in terms of mass percentage, its formula includes: 70% photosensitive resin, 15% IBOM diluent, 5% TPO photoinitiator, 5% BYK163 dispersant, 0.1% polyvinyl alcohol, 0.3% BYK163 dispersant, 0.2% polyvinylpyrrolidone.

[0038] The photosensitive resin for printing the stress detection layer of the pressure sensor is configured by adding conductive fillers such as multi-walled carbon nanotubes. In terms of mass percentage, its formula includes: 5% multi-walled carbon nanotubes, 4.5% graphene, 60% photosensitive resin, 20% IBOM diluent, 5% TPO photoinitiator, 5% BYK163 dispersant, 0.1% polyvinyl alcohol, 0.3% BYK163 dispersant, 0.2% polyvinylpyrrolidone.

[0039] (1) Add the prepared material substrate into a multi-material DLP printing device, import the three-dimensional model of the flexible installation layer into the DLP printing device, and configure the relevant parameters for DLP 3D printing as follows: the wavelength of the DLP ultraviolet light source is 405 nm, the ultrasonic cleaning time of the liquid tank is 30 s - 40 s, and the fan drying temperature is 20 - 30 °C. Then add the flexible resin into the device and perform the printing of the flexible installation layer.

[0040] (2) After the printing of the flexible installation layer is completed, sequentially replace the multi-functional platform of the printing device to the ultrasonic cleaning station and the drying station to complete the cleaning and drying of the printed parts.

[0041] (3) Establish a three-dimensional model of the stress detection layer through the flexible installation layer, then import the three-dimensional model of the stress detection layer into the DLP printing device, and configure the relevant parameters for DLP 3D printing as follows: the wavelength of the DLP ultraviolet light source is 405 nm, the ultrasonic cleaning time of the liquid tank is 30 s - 40 s, and the fan drying temperature is 20 - 30 °C. Then add the configured mixed substrate and perform the printing of the flexible installation layer.

[0042] (4) After the printing of the stress detection layer is completed, sequentially replace the multi-functional platform of the printing device to the ultrasonic cleaning station and the drying station to complete the cleaning and drying of the printed parts.

[0043] (5) Next, perform the lead operation, lead out from both ends of the place where the strain sensor is coated with the cured conductive paste, and connect it to the resistance measuring device.

[0044] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for fabricating a surface-exposed additive of a conformable stress sensor for an aviation complex component, characterized in that, The stress sensor has a two-layer structure, including a flexible mounting layer and a stress detection layer; the flexible mounting layer is made of flexible resin without adding any conductive fillers and is formed by DLP printing. The model of the flexible mounting layer is from an aviation complex component, and a model with the same outer contour curve as the model is established through 3D scanning to meet the requirement of fitting the aviation complex structure. The stress detection layer has the same outer contour curve as the three-dimensional model of the flexible mounting layer. A variety of materials such as conductive fillers and diluents are added to the flexible resin and formed by DLP printing to meet the stress detection of aviation complex components. Leads are added to the stress detection layer and led out from both ends of the place where the cured conductive paste is covered on the stress detection layer and connected to a resistance measuring device. It includes the following steps: Step S1: Perform 3D scanning on the aviation complex component, establish a model with the same outer contour curve as the aviation complex model through 3D scanning to meet the requirement of fitting the aviation complex structure, and then establish a three-dimensional model of the flexible mounting layer. Step S2: Import the three-dimensional model of the flexible mounting layer into the DLP printing device, and configure the relevant parameters of DLP 3D printing as follows: DLP ultraviolet light source wavelength 405nm, liquid tank ultrasonic cleaning time 30s - 40s, fan drying temperature 20 - 30°C. Then add flexible resin to the device and perform the printing of the flexible mounting layer. Step S3: After the printing of the flexible mounting layer is completed, sequentially replace the multi-functional platform of the printing device to the ultrasonic cleaning station and the drying station to complete the cleaning and drying of the printed parts. Step S4: Establish a three-dimensional model of the stress detection layer through the flexible mounting layer, then import the three-dimensional model of the stress detection layer into the DLP printing device, and configure the relevant parameters of DLP 3D printing as follows: DLP ultraviolet light source wavelength 405nm, liquid tank ultrasonic cleaning time 30s - 40s, fan drying temperature 20 - 30°C. Then add the configured mixed matrix and perform the printing of the stress detection layer. Step S5: After the printing of the stress detection layer is completed, sequentially replace the multi-functional platform of the printing device to the ultrasonic cleaning station and the drying station to complete the cleaning and drying of the printed parts. Step S6: Next, perform the lead operation, lead out from both ends of the place where the strain sensor is covered with the cured conductive paste, and connect to a resistance measuring device.

2. The surface exposure additive manufacturing method of the conformable stress sensor for aviation complex components according to claim 1, wherein The flexible mounting layer of the stress sensor is made of flexible photosensitive resin with a thickness between 1mm and 2mm.

3. The surface exposure additive manufacturing method of the conformable stress sensor for aviation complex components according to claim 1, characterized in that, The stress detection layer of the stress sensor is prepared from a composite material. Multi-walled carbon nanotubes are added as conductive fillers to the flexible photosensitive resin, and TPO photoinitiator, IBOM diluent, and BYK163 dispersant are added and ultrasonically stirred for 30 minutes to obtain a mixed matrix.

4. The surface exposure additive manufacturing method of the conformable stress sensor for aviation complex components according to claim 1, wherein, The detection layer of the stress sensor has the same outer contour curve as the three-dimensional model of the flexible mounting layer, and the layer thickness increases with a printing thickness between 2mm and 4mm.

5. The surface exposure additive manufacturing method of the conformable stress sensor for aerospace complex components according to claim 1, characterized in that The resistance value of the stress sensor changes with the applied stress, and the change rate of the resistance is proportional to the magnitude of the stress.

6. The surface exposure additive manufacturing method of the conformable stress sensor for aviation complex components according to claim 1, wherein After the stress detection layer of the stress sensor is printed by DLP, sequentially replace the multi-functional platform of the printing device to the ultrasonic cleaning station and the drying station to complete the cleaning and drying of the printed parts.

7. The surface exposure additive manufacturing method of the conformable stress sensor for aviation complex components according to claim 1, wherein The DLP printing completes the flexible mounting layer of the stress sensor, and the multi-functional platform of the printing device is sequentially replaced to the ultrasonic cleaning station and the drying station to complete the cleaning and drying of the printed parts.

8. The surface exposure additive manufacturing method of the conformable stress sensor for aviation complex components according to claim 1, characterized in that The leads added to the stress detection layer are copper, gold, and silver wires with a diameter ranging from 2 μm to 2 mm, and the leads are bonded to the cured conductive paste through nano silver paste.

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