CN114985939A - Method for removing paint on surface of carbon fiber reinforced resin matrix composite material containing conductive layer - Google Patents
Method for removing paint on surface of carbon fiber reinforced resin matrix composite material containing conductive layer Download PDFInfo
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- CN114985939A CN114985939A CN202210550887.6A CN202210550887A CN114985939A CN 114985939 A CN114985939 A CN 114985939A CN 202210550887 A CN202210550887 A CN 202210550887A CN 114985939 A CN114985939 A CN 114985939A
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- laser
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- conductive layer
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- carbon fiber
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/36—Removing material
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/36—Removing material
- B23K26/40—Removing material taking account of the properties of the material involved
- B23K26/402—Removing material taking account of the properties of the material involved involving non-metallic material, e.g. isolators
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K26/00—Working by laser beam, e.g. welding, cutting or boring
- B23K26/70—Auxiliary operations or equipment
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
- Y02W30/00—Technologies for solid waste management
- Y02W30/50—Reuse, recycling or recovery technologies
- Y02W30/62—Plastics recycling; Rubber recycling
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- Engineering & Computer Science (AREA)
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- Optics & Photonics (AREA)
- Plasma & Fusion (AREA)
- Mechanical Engineering (AREA)
- Laser Beam Processing (AREA)
- Laminated Bodies (AREA)
Abstract
The invention provides a method for removing paint on the surface of a carbon fiber reinforced resin matrix composite material containing a conductive layer; the method comprises the following steps: step 1, fixing a sample piece to be processed on a working platform, and aligning one surface coated with a paint layer to a laser cleaning head; step 2, opening a pulse laser, and selecting laser parameters of high power, low frequency and wide pulse to remove part of the paint layer on the surface of the material; step 3, repeating the step 2 until a small amount of paint layers remain; step 4, adopting a pulse laser which is the same as the pulse laser in the step 2, selecting laser parameters of low power, high frequency and narrow pulse to remove the residual paint layer on the surface of the material, and carrying out strengthening treatment on the conductive layer; and 5, closing the laser, removing the waste materials remained on the surface of the sample piece, and taking out the sample piece. The method adopts the pulse laser to remove the paint coating, realizes the nondestructive removal and performance enhancement of the conducting layer through the layered removal and laser enhancement, has high efficiency and wide application range, and has important significance on the repair technology of the aircraft.
Description
Technical Field
The invention relates to the technical field of advanced laser manufacturing of the surface of an airplane; in particular to a method for removing paint on the surface of a carbon fiber reinforced resin matrix composite material containing a conductive layer.
Background
The carbon fiber reinforced resin matrix composite material is widely applied to modern aviation aircrafts. Because the harm of the lightning stroke phenomenon is considered, other metal powder such as aluminum powder, copper powder, tin powder and the like is generally sprayed on the surface of a material by high pressure in industry to form a conductive layer, thereby playing a role in protection and avoiding the harm caused by the lightning stroke. Before leaving the factory, the surface of the aviation aircraft is painted, so that the corrosion resistance, the impact resistance and the strong ultraviolet irradiation resistance of the aircraft in a severe service environment are improved. The paint layer on the surface of the airplane can be aged, cracked, partially peeled off and the like due to the influence of various factors such as sunlight, temperature, humidity and the like. Therefore, the aviation aircraft needs to carry out work operations such as paint removal, repainting and the like periodically.
The traditional paint removing method mainly comprises the following steps: chemical removal and mechanical removal. The traditional removal method has low working efficiency, severe working environment, serious pollution and high cost; and thus damage to the conductive layer, thereby reducing the conductive efficiency. The traditional paint removing method has the phenomena of chemical corrosion and mechanical vibration, and the combination mode between the conducting layer and the substrate is the mechanical combination between metal and resin, so the combination strength between the conducting layer and the substrate can be greatly reduced by using the traditional paint removing method, and the protection effect of the conducting layer on the substrate is finally influenced. The conventional method is gradually difficult to be applied to modern aerospace materials having a complicated structure.
Disclosure of Invention
The invention aims to provide a method for removing paint on the surface of a carbon fiber reinforced resin matrix composite material containing a conductive layer.
The invention is realized by the following technical scheme:
the invention relates to a method for removing paint on the surface of a carbon fiber reinforced resin matrix composite material containing a conductive layer, which comprises the following steps:
and 5, closing the laser, removing the residual waste on the surface of the sample piece, and taking out the sample piece.
Preferably, the pulse laser is Nd: YAG laser, CO 2 A laser or a fiber laser.
Preferably, the laser wavelength of the pulse laser is in the range of 100nm-30 um; the average power of the pulse laser ranges from 100W to 300W.
Preferably, the pulsed laser adopts a galvanometer system to scan light beams, the laser scanning speed is 500mm/s-10000mm/s, and the overlapping rate range between adjacent pulses is 1% -99%. Specifically, the on-delay and off-delay of the laser pulse and the scanning mode of the laser are controlled and set by a computer program.
Preferably, in step 2, the output power of the pulse laser is in a range of 20% to 100%; the frequency range of the pulse laser is 1kHz-500 kHz; the output pulse width range of the pulse laser is 200ns-500 ns.
Preferably, in step 4, the output power of the pulse laser is in a range of 1% -20%; the output frequency range of the pulse laser is 500kHz-2000 kHz; the output pulse width range of the pulse laser is 1ns-200 ns.
Preferably, in step 4, the conductive layer is prepared from pure metal powder of aluminum powder, copper powder or tin powder.
Preferably, in step 4, the conductive layer is prepared by mixing pure metal powders of aluminum powder, copper powder and tin powder.
The invention has the following advantages:
(1) the method adopts a pulse laser to remove the paint coating on the surface of the carbon fiber reinforced resin matrix composite material containing the conductive layer; the principle of the invention is as follows: the paint coating is thoroughly removed through an ablation effect, a thermoelastic vibration effect and a plasma impact effect generated when the laser acts on the surface of the material, and compared with a traditional paint removing mode, the method has the advantages of high efficiency, environmental protection, non-contact, high precision, wide application range and the like.
(2) The invention adopts a mode of removing for many times, controls or adjusts the laser parameters when removing for different times, and utilizes the difference of the interaction forms of the laser and the material under different parameters to realize the nondestructive removal of the conducting layer, simultaneously strengthen the structure of the conducting layer and further improve the conducting efficiency.
Drawings
FIG. 1 is a schematic diagram of a structure of a carbon fiber reinforced resin-based composite material containing a conductive layer according to the present invention and a schematic diagram of a laser cleaning process;
in the figure, 1 is a laser pulse beam, 2 is a paint coating, 3 is a conductive layer, and 4 is a carbon fiber reinforced resin matrix composite material base layer.
Detailed Description
The present invention will be described in detail with reference to specific examples. It should be noted that the following examples are only illustrative of the present invention, but the scope of the present invention is not limited to the following examples.
Example 1
The embodiment relates to a paint removing method for the surface of a carbon fiber reinforced resin matrix composite material containing a conductive layer, which comprises the following steps:
firstly, cutting a carbon fiber reinforced resin matrix composite (a paint coating 2, a conducting layer 3 and a carbon fiber reinforced resin matrix composite base layer 4 from top to bottom in sequence) which is coated with a paint layer 2 on the surface and contains an aluminum powder conducting layer to a proper size by using a cutting machine, wherein the specific structure is shown in figure 1; fixing a sample piece to be processed on a working platform, and aligning one surface coated with a paint layer 2 with a laser pulse beam 1;
YAG laser with average power of 300W is used for removing the surface paint layer 2, the used laser wavelength is 1064nm, the laser spot is circular, the diameter is 50um, the laser output power is 30%, the pulse frequency is 200kHz, the pulse width is 200ns, the scanning speed is 1000mm/s, a bow-shaped scanning mode is adopted, and the pulse overlapping rate is 50%;
thirdly, reducing the output power of the laser to 20% by using the same laser in the second step, and keeping the other parameters unchanged;
fourthly, using the same laser in the second step, adjusting the output power of the laser to be 5 percent, the pulse frequency to be 1000kHz, the pulse width to be 50ns, the scanning speed to be 8000mm/s and the lap joint rate to be 50 percent;
and step five, closing the laser, cleaning up the residual waste on the surface of the sample piece, and taking out the sample piece.
Example 2
The embodiment relates to a paint removing method for the surface of a carbon fiber reinforced resin matrix composite material containing a conductive layer, which comprises the following steps:
firstly, cutting a carbon fiber reinforced resin matrix composite material (a paint coating 2, a conducting layer 3 and a carbon fiber reinforced resin matrix composite material base layer 4 from top to bottom) which is coated with paint 2 and contains an aluminum powder conducting layer to a proper size by using a cutting machine, fixing a sample piece to be processed on a working platform, and aligning one surface coated with a paint layer to a laser pulse beam 1;
second, C0 with average power of 100W is used 2 The laser removes the surface paint layer, the laser wavelength is 10.6nm, the laser spot is square, the side length is 50um, the laser output power is 50%, the pulse frequency is 300kHz, the pulse width is 300ns, the scanning speed is 900mm/s, a bow-shaped scanning mode is adopted, and the pulse overlap ratio is 30%;
thirdly, repeating the second step;
fourthly, using the same laser in the second step, adjusting the output power of the laser to be 10%, the pulse frequency to be 1500kHz, the pulse width to be 100ns, the scanning speed to be 5000mm/s and the lap joint rate to be 50%;
and step five, closing the laser, cleaning up the residual waste on the surface of the sample piece, and taking out the sample piece.
Example 3
The embodiment relates to a paint removing method for the surface of a carbon fiber reinforced resin matrix composite material containing a conductive layer, which comprises the following steps:
firstly, cutting a carbon fiber reinforced resin matrix composite material (a paint coating 2, a conducting layer 3 and a carbon fiber reinforced resin matrix composite material base layer 4 from top to bottom) which is coated with paint and contains a copper powder conducting layer on the surface to a proper size by using a cutting machine, fixing a sample piece to be processed on a working platform, and aligning one surface coated with a paint layer to a laser pulse beam 1;
secondly, removing a surface paint layer by using a fiber laser with the average power of 250W, wherein the used laser wavelength is 2100nm, the laser spot is circular, the diameter is 100um, the laser output power is 50%, the pulse frequency is 300kHz, the pulse width is 200ns, the scanning speed is 1000mm/s, a bow-shaped scanning mode is adopted, and the pulse overlapping rate is 80%;
thirdly, using the same laser in the second step, adjusting the output power of the laser to be 5%, the pulse frequency to be 1000kHz, the pulse width to be 100ns, the scanning speed to be 4000mm/s and the pulse lap-joint rate to be 20%;
and fourthly, closing the laser, cleaning up the residual waste on the surface of the sample piece, and taking out the sample piece.
Example 4
The embodiment relates to a paint removing method for the surface of a carbon fiber reinforced resin matrix composite material containing a conductive layer, which comprises the following steps:
firstly, cutting a carbon fiber reinforced resin matrix composite material (a paint coating 2, a conducting layer 3 and a carbon fiber reinforced resin matrix composite material base layer 4 from top to bottom in sequence) which is coated with paint and contains an aluminum/nickel bi-component metal powder conducting layer on the surface to a proper size by using a cutting machine, fixing a sample piece to be processed on a working platform, and aligning the surface coated with the paint layer to a laser pulse beam 1;
second, C0 with average power of 100W is used 2 Laser device for removing surface paint layerThe laser wavelength is 10.6nm, the laser spot is circular, the diameter is 1mm, the laser output power is 30%, the pulse frequency is 500kHz, the pulse width is 250ns, the scanning speed is 800mm/s, a bow-shaped scanning mode is adopted, and the pulse overlapping rate is 60%;
thirdly, using the same laser in the second step, adjusting the output power of the laser to be 10%, the pulse frequency to be 1100kHz, the pulse width to be 100ns, the scanning speed to be 2000mm/s and the pulse lap-joint rate to be 10%;
and fourthly, closing the laser, cleaning up the waste materials remained on the surface of the sample piece, and taking out the sample piece.
The method adopts a pulse laser to remove the paint coating on the surface of the carbon fiber reinforced resin matrix composite material containing the conductive layer; the principle of the invention is as follows: the paint coating is thoroughly removed through the ablation effect, the thermoelastic vibration effect and the plasma impact effect generated when the laser acts on the surface of the material, and compared with the traditional paint removing mode, the method has the advantages of high efficiency, environmental protection, non-contact, high precision, wide application range and the like. The method adopts the pulse laser to remove the paint coating, realizes the nondestructive removal and performance enhancement of the conducting layer through the layered removal and laser enhancement effects, has high efficiency and wide application range, and has important significance on the repair technology of the aviation aircraft.
The foregoing description of specific embodiments of the present invention has been presented. It is to be understood that the present invention is not limited to the specific embodiments described above, and that various changes or modifications may be made by one skilled in the art within the scope of the appended claims without departing from the spirit of the invention.
Claims (8)
1. A method for removing paint on the surface of a carbon fiber reinforced resin matrix composite material containing a conductive layer is characterized by comprising the following steps:
step 1, fixing a sample piece to be processed on a working platform, and aligning one surface coated with a paint layer to a laser cleaning head;
step 2, opening a pulse laser, and selecting laser parameters of high power, low frequency and wide pulse to remove part of the paint layer on the surface of the material;
step 3, repeating the step 2 until a small amount of paint layers remain;
step 4, adopting a pulse laser which is the same as the pulse laser in the step 2, selecting laser parameters of low power, high frequency and narrow pulse to remove the residual paint layer on the surface of the material, and carrying out strengthening treatment on the conductive layer;
and 5, closing the laser, removing the residual waste on the surface of the sample piece, and taking out the sample piece.
2. The method for removing paint on the surface of the carbon fiber reinforced resin-based composite material with the conductive layer according to claim 1, wherein the pulse laser is Nd-YAG laser and CO 2 A laser or a fiber laser.
3. The method for removing paint on the surface of carbon fiber reinforced resin-based composite material containing conductive layer according to claim 1, wherein the laser wavelength of the pulse laser is in the range of 100nm-30 um; the average power of the pulse laser is in the range of 100W-300W.
4. The method for removing paint from the surface of carbon fiber reinforced resin-based composite material with a conductive layer according to claim 1, wherein the pulsed laser adopts a galvanometer system to scan the light beam, the laser scanning speed is 500mm/s-10000mm/s, and the overlapping rate between adjacent pulses is 1% -99%.
5. The method for removing paint on the surface of the carbon fiber reinforced resin-based composite material with the conductive layer according to claim 1, wherein in the step 2, the output power of the pulse laser is in a range of 20% -100%; the frequency range of the pulse laser is 1kHz-500 kHz; the output pulse width range of the pulse laser is 200ns-500 ns.
6. The method for removing paint on the surface of the carbon fiber reinforced resin-based composite material with the conductive layer according to claim 1, wherein in the step 4, the output power of the pulse laser is in a range of 1% -20%; the output frequency range of the pulse laser is 500kHz-2000 kHz; the output pulse width range of the pulse laser is 1ns-200 ns.
7. The method for removing paint on the surface of the carbon fiber reinforced resin-based composite material with the conductive layer according to claim 1, wherein in the step 4, the conductive layer is prepared from aluminum powder, copper powder or tin powder pure metal powder.
8. The method for removing paint from the surface of the carbon fiber reinforced resin-based composite material with the conductive layer according to claim 1, wherein in the step 4, the conductive layer is prepared by mixing aluminum powder, copper powder and tin powder which are pure metal powders.
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|---|---|---|---|---|
| US4756765A (en) * | 1982-01-26 | 1988-07-12 | Avco Research Laboratory, Inc. | Laser removal of poor thermally-conductive materials |
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| CN109821823A (en) * | 2019-04-08 | 2019-05-31 | 哈尔滨工业大学 | A kind of CO2Laser/ps pulsed laser and ns pulsed laser compound cleaning method |
| CN110449418A (en) * | 2019-09-19 | 2019-11-15 | 中国民用航空飞行学院 | A kind of surface paint removal method and its application of Aluminum alloy airplane skin |
| CN111014185A (en) * | 2019-11-06 | 2020-04-17 | 株洲国创轨道科技有限公司 | Method and device for cleaning paint by laser |
| CN112827947A (en) * | 2021-02-19 | 2021-05-25 | 铭镭激光智能装备（河源）有限公司 | Laser-based paint removal method and system, terminal device and storage medium |
| CN113732519A (en) * | 2021-09-03 | 2021-12-03 | 陈亚军 | Design method for laser paint removal process parameters of aluminum alloy aircraft skin |
| CN113877893A (en) * | 2021-08-20 | 2022-01-04 | 西安飞机工业（集团）有限责任公司 | Method for laser cleaning of cadmium coating on surface of workpiece and laser cleaning device |
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2022
- 2022-05-20 CN CN202210550887.6A patent/CN114985939B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4756765A (en) * | 1982-01-26 | 1988-07-12 | Avco Research Laboratory, Inc. | Laser removal of poor thermally-conductive materials |
| CN108160620A (en) * | 2017-12-29 | 2018-06-15 | 武汉金顿激光科技有限公司 | A kind of face of weld Paint removing process |
| CN108787636A (en) * | 2018-08-01 | 2018-11-13 | 湖南信奥光电技术有限公司 | A kind of method of laser cleaning removal composite material surface enamelled coating |
| CN109821823A (en) * | 2019-04-08 | 2019-05-31 | 哈尔滨工业大学 | A kind of CO2Laser/ps pulsed laser and ns pulsed laser compound cleaning method |
| CN110449418A (en) * | 2019-09-19 | 2019-11-15 | 中国民用航空飞行学院 | A kind of surface paint removal method and its application of Aluminum alloy airplane skin |
| CN111014185A (en) * | 2019-11-06 | 2020-04-17 | 株洲国创轨道科技有限公司 | Method and device for cleaning paint by laser |
| CN112827947A (en) * | 2021-02-19 | 2021-05-25 | 铭镭激光智能装备（河源）有限公司 | Laser-based paint removal method and system, terminal device and storage medium |
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| CN113732519A (en) * | 2021-09-03 | 2021-12-03 | 陈亚军 | Design method for laser paint removal process parameters of aluminum alloy aircraft skin |
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