CN115768585A - Method for treating surfaces with IR lasers - Google Patents

Abstract

A method for pretreating polymer-coated surfaces (11) with particles and/or coatings is described, wherein a laser is emitted by means of a laser source (110), in particular a pulsed infrared laser beam (111) in the near infrared range is generated with a pulsed energy density of 0.01J/cm2 to 50J/cm 2. The method further comprises directing the laser light as a laser beam (111) onto the surface (11) by a deflection unit (115) and moving the laser light along a path (40) over the surface (11). The emission of the pulsed laser comprises setting the pulse energy density such that first particles and/or coating material of the surface (11) facing the laser beam (111) absorb the pulsed infrared laser (111) and a portion of the surface is detached, wherein the layer thickness of the polymer after detachment is greater than or equal to 50%, preferably greater than or equal to 75%, particularly preferably greater than or equal to 90%, of the initial layer thickness of the polymer.

Description

Method for treating surfaces with IR lasers

technical field

The invention relates to a method for treating surfaces with an infrared laser. In particular, the invention relates to a method for treating a polymer-coated surface with a near-infrared laser from a laser source with a pulse energy density of 0.01 J/cm2 to 50 J/cm2.

Background technique

Many components must have good adhesion to the paint to be applied so that the paintwork has a long service life. In particular, aircraft components forming the outer skin of the aircraft are often subjected to high loads, such as severe temperature fluctuations and, of course, high overflow velocities. These exterior paint layers must adhere permanently to the components very well. For this purpose, the surface of the components (component materials, connections such as rivet heads, seals, hinges, etc.), but also the existing external coatings (primers, antistatic paints, anti-erosion protection layers, anti-corrosion Protective layers, old paint, etc.) are cleaned on the one hand (removal of adhering dirt) and on the other hand are prepared for painting (ie activate the surface or exterior coating).

In the previous pretreatment and cleaning processes, water- or solvent-based cleaning methods were used, followed by grinding processes. Grinding residues must then also be removed in the final cleaning process. This labor-intensive pretreatment of aircraft components is not only expensive but also in most cases requires the use of chemical agents which must be properly collected, recycled and/or disposed of. Furthermore, during grinding, the thickness of the material being abraded can change significantly, so that in some cases primers or other previously applied layers can be damaged.

DE 10 2009 029 915 A1 proposes the use of a CO 2 laser and directing the resulting laser beam onto the surface of the component. However, pretreatment with CO2 lasers can cause severe paint stripping due to the wavelength. This can lead to changes at least in the surface area which, due to the larger laser spot (as used in DE 10 2009 029 915 A1), produce macroscopic changes in the surface structure which are visible even when coated Can still be seen after painting and affect the painted appearance.

Contents of the invention

It is therefore the object on which the present invention is based to provide an improved method for the pretreatment of surfaces, especially polymer-coated surfaces.

This object is achieved by a method having the features of claim 1 .

According to a first aspect for better understanding of the present disclosure, an apparatus for pretreating a surface includes: a laser source configured to emit laser light; and a deflection unit configured to direct the laser light As the laser beam is directed onto the surface and is moved over the surface along a certain path. The laser source can be a conventional laser, for example an industrial laser. The deflection unit can be embodied, for example, as an optical deflection unit with one or more mirrors and/or prisms.

The laser source is configured to generate an infrared laser beam in the near infrared range. The laser source can in particular generate a pulsed infrared laser beam with a pulse energy density of 0.01 J/cm 2 to 50 J/cm 2 . The pulse energy density refers to the area energy of the laser beam during a single pulse, that is, the pulse energy (J) of each focal diameter (the cross-sectional area of the laser beam or the area of the laser spot). For example, the pulse energy density may preferably be 0.1 J/cm 2 to 10 J/cm 2 and particularly preferably 0.5 J/cm 2 to 1 J/cm 2 .

By means of the pulsed energy density, energy can be introduced into a surface (for example of an aircraft component) in a targeted manner and this energy input can activate the surface. However, the surface and associated components are not heated in its depth (layer thickness). This prevents surface changes due to excessive thermal loading.

Furthermore, near-infrared laser beams, ie laser beams in the short-wave infrared range between 810 nm and 5,000 nm, have the advantage that very little thermal energy is introduced into the entire surface to be treated. Preferably, a laser source can be used which generates a laser beam with a wavelength between 950 nm and 1500 nm, particularly preferably with a wavelength of 1064 nm.

By combining near-infrared laser beams with suitable processing strategies, damage or visible surface changes can be avoided. For example, an infrared laser beam can be used to activate the layer in a targeted manner in layers with infrared light-absorbing particles. For example, the layers can be heated in a targeted manner by an infrared laser beam, so that the layers are at least partially detached and/or at least partially detached from the underlying layers.

The surface can be, for example, a polymer-coated surface, for example a painted surface and/or a surface with particles and/or paint. In order to remove only part of the polymer layer, the pulse fluence of the laser beam can be set such that the layer thickness of the polymer at the location of the laser action is greater than or equal to 50% of the initial (untreated) layer thickness of the polymer , preferably greater than or equal to 75%, particularly preferably greater than or equal to 90%. In other words, at most 50%, preferably at most 25% and particularly preferably at most 10%, of the initial polymer layer is removed. Of course, it is also possible to remove the entire polymer layer at the location where the laser action takes place.

Thus, only a very thin layer or a small outer part of the uppermost, outer layer can be activated by means of a near-infrared laser beam with the mentioned pulse energy density. Activation is understood here to mean the removal of the (very thin) outer parts of the layer, so that the layer adheres better to other layers subsequently applied thereon, for example (further) paintwork. In other words, the already existing layer, viewed from the outside, with the first particles excited by the infrared light is at least partially peeled off.

The layer with particles is in particular a layer comprising the polymer used to coat the surface. The polymer layer may, for example, contain fillers which cause inhomogeneous absorption of the laser light. For example, the polymer layer may be a paint already present on the surface. Typically, various particles or paint coatings are used here, such as titanium dioxide (for light or white colors) up to carbon black particles (for dark colors or black/gray). These particles/coatings are very well suited for absorbing infrared laser light and thus activating the layer. At the mentioned pulse energy densities, these particles/coatings can induce detachment within the layer as well as from the underlying layer material. For example, these particles/paints can change their consistency under the influence of the laser, so that part of the layer adjacent to these particles/paints can be detached, and/or these particles/paints can be (be) removed from the layer material located below them . This makes it possible to achieve a thin and uniform treatment of the surface.

Dirt on the outermost layer of the component can also be thermally activated by a near-infrared laser beam, thereby removing it. Layers lying beneath the dirt, in particular layers transparent to infrared light, are not activated by the laser beam and therefore remain on the component.

Furthermore, for a Primer or other base paint, the outermost surface layer may be (trans)transparent to infrared light, and then viewing through the thickness of the layer reveals the colored paint. Thus, by means of a near-infrared laser beam it is possible to remove the outermost clear layer of the primer or basecoat by thermally activating the “first layer” of the primer up to or together with the color paint. Component surfaces pretreated in this way have very good adhesion to subsequently applied paintwork.

In an implementation variant, the laser source can also be configured to set the infrared laser beam and/or the pulse energy density so that the effective surface area of the surface processed by the infrared laser beam is obtained to be greater than or equal to 5%, preferably greater than or equal to A microscopic increase of 25% and particularly preferably greater than or equal to 50%. A microscopic increase in the effective surface area compared to the initial (untreated) polymer surface must be taken into account here.

Merely as an example, a laser source with an average power between 5W and 1000W, preferably with an average power of 50W to 500W, may be used. Such a laser source is particularly compact and therefore light-weight, which allows a simpler design of the device as a whole.

In an implementation variant, the device can also comprise at least one robotic arm fastened to the deflection unit. The at least one robotic arm may be configured to effect movement relative to the surface. This enables the deflection unit to be moved over a larger area of the surface or the component comprising the surface or the entire component. Thus, the treatable area on the component is not limited solely by the deflection unit. Furthermore, the deflection unit can always be optimally aligned on the surface of the component by means of the robot arm which is movable about three axes. In particular, the distance between the deflection unit and the surface of the component and the angle of incidence of the laser beam on the surface of the component can be kept as constant as possible. For example, the angle of incidence of the laser beam on the surface of the component can be kept as close as possible to 90°, for example in a range between 85° and 95°.

Alternatively or additionally, the apparatus may comprise a table fastened to the member comprising the surface. In this case, the table can be configured to carry out at least one two-dimensional movement relative to the deflection unit. The movement can of course also be carried out relative to the robot arm. As a result, the treatable area of the component surface can be further increased, especially if not all areas of the component surface can be reached by the robotic arm alone.

In another implementation variant, the device may further comprise a fiber optic line arranged between the laser light source and the deflection unit, the fiber optic line being configured to guide the laser light of the laser source to the deflection unit. The fiber optic line can be realized, for example, in the form of a fiber optic cable. The mostly heavy and complex laser source can be partially separated from the deflection unit by means of the fiber optic line, so that the movement of the deflection unit over the component surface is facilitated. Fiber optic lines are particularly advantageous in interaction with robotic arms, since fiber optic lines can easily assist the movement of the robotic arm. Compared with conventional CO2 lasers, near-infrared lasers can be transmitted through fiber optic lines. Furthermore, CO2 laser sources are in most cases more complex and therefore heavier in their construction. Therefore, the use of near-infrared lasers proposed here has many advantages, especially in the automated preprocessing of large aircraft components.

In an implementation variant, the laser source can also be configured to generate pulses with a length or duration of 0.01 ns to 10,000 ns, 0.1 ns to 10,000 ns, 1 ns to 10,000 ns, 1 ns to 1000 ns, or 10 ns to 1000 ns, or An infrared laser beam having a range (preferably 1 ns to 1000 ns) of a combination of these ranges of values. The total power input into the surface can thus be more precisely controlled.

In another implementation variant, the deflection unit can also be configured to generate on the surface diameters between 1 μm and 10,000 μm, preferably between 10 μm and 1,000 μm and particularly preferably between 10 μm and 100 μm laser point. Such a small laser spot enables a uniform treatment of surfaces regardless of their surface structure. For example, aircraft components are assembled together with fastening means, such as rivets. However, the rivet heads can form protrusions on the surface of the aircraft component. Due to the very small laser spot, the laser beam can be directed optimally to any section of the aircraft component, including such fastening means and other elements that are spatially distinct from the surface. Especially compared to conventional grinding processes, which can remove more material on such bumps if used incorrectly, the advantages of near-infrared lasers are evident.

Furthermore, the laser source can be configured for setting the energy distribution of the laser spot in the focus of the laser beam according to a specific profile. The energy distribution can be configured, for example, as a flat-top profile or a Gaussian profile. Furthermore, the laser source can also be configured for setting circular or angular beam profiles.

In yet another implementation variant, the device may further comprise at least one sensor configured for identifying surface properties of the surface. The sensor can be configured, for example, to detect and analyze laser light reflected by the surface. Thus, for example, an orientation of the surface can be determined, from which the orientation of the laser beam can be adapted. It is also possible to obtain the dirt or color of the outer layer of the surface. Based on this information, the laser parameters (frequency, pulse length, laser spot size, wavelength, energy density, etc.) can be set by the laser source in order to achieve the best processing of the surface. /activation.

In another implementation variant, the deflection unit can also be configured to move the laser points stepwise along the path, wherein the temporally earlier laser point spatially overlaps the temporally following laser point. The deflection unit is controlled in such a way that the laser beam always hits a point on the surface, wherein the point immediately following in time has an intersecting surface (overlapping surface). The energy applied by the laser beam acts on the intersecting surface more frequently because the area is treated multiple times by the laser beam, accumulating the laser power brought onto/into the surface. By changing the size of the intersecting surface, ie by changing the step size of the step-by-step movement of the laser point, the energy input into the surface can be determined jointly at least in part.

Alternatively or additionally, in another implementation variant, the deflection unit can also be configured to move the laser spot line by line along the path. For example, predetermined regions can be treated by means of laser spots arranged row by row. Here, successive laser spots may be directed to traverse in a serpentine fashion (ie along a continuous S-shaped path in which the scanning directions on adjacent rows are opposite). Alternatively, successive laser spots may be directed to traverse in always the same scan direction.

Furthermore, it is also possible for the temporally earlier laser points of the first row to overlap spatially with the temporally following laser points of the second row. In other words, the laser spots in the first row and the adjacent laser spots in the second row form an intersecting plane (overlapping plane). The laser beam applies more energy to this intersecting surface because the area is treated multiple times by the laser beam. By varying the dimensions of the intersecting areas, ie varying the line spacing of the line-by-line movement of the laser spot, the energy input into the surface can be determined at least in part jointly.

For example, the line spacing between two adjacent lines of the path is between 0.001 mm and 10 mm, preferably between 0.01 mm and 1 mm and particularly preferably between 0.01 mm and 0.1 mm. In this case, a smaller spacing between the rows can be selected if the laser power and thus the resulting pulse fluence are set to be small. For example, when the laser power is 10W, the line spacing can be set to 0.01mm. In another example, the line spacing may be set to 0.05mm when the laser power is 100W. In the case of an exemplary laser spot size of 100 μm, ie 0.1 mm, the overlapping areas are correspondingly larger or smaller.

Of course, the line spacing can also be related to the laser spot size (area or diameter of the laser spot). For example, the feed between two rows may be between 5% and 95% of the laser spot size, preferably between 30% and 60%.

In another implementation variant, the laser source can also be configured for generating a pulsed laser beam with a frequency between 50 kHz and 10 MHz (10,000 kHz), preferably at a frequency of 150 kHz. A laser beam pulsed in this way makes it possible to determine the cumulative input energy per region (of the surface) in a targeted manner. A uniform surface treatment can thus be achieved.

Furthermore, the deflection unit can be configured, for example, to move the laser spots along the path in such a way that a pulsed laser beam hits each laser spot 1 to 15 times, preferably between 2 and 5 times. In other words, the pulsed laser beam is irradiated to a given laser spot several times before the deflection unit steers the laser beam to the next adjacent laser spot. The cumulative input energy per area is also determined by the frequency with which the same area on the surface is treated with the laser beam. The treatment of the surface can be determined by changing the striking frequency of the laser beam on the same laser point (same area).

In another implementation variant, the deflection unit can also be configured for a distance along the path between 100 mm/s and 1,000,000 mm/s, preferably between 500 mm/s and 500,000 mm/s and particularly preferably The laser beam is moved at a scanning speed between 500mm/s and 500,000mm/s. The scanning speed of the laser beam can correspond, for example, to the movement of the laser spot within a certain line.

Depending on the implementation variant, different path parameters and/or laser parameters can be varied in order to achieve a desired cumulative input energy into the surface. For example, the thickness of the removed layer on the surface of the component can be determined from this. Path parameters include: the travel speed of the laser (scanning speed), the distance between rows of the path, the distance between laser spots along the path and thus the size of the overlapping area of adjacent laser spots. Laser parameters include: laser energy density, laser pulse length, pulse frequency, laser spot size (eg diameter), laser wavelength.

By way of example only, the deflection unit may also be configured for determining the path on the surface such that the laser fluence (irradiation density) on the surface is between 800 mJ/cm2 and 9000 mJ/cm2. In this case, various path parameters and/or laser parameters can be varied in order to achieve the desired laser fluence.

In yet another implementation variant, the device can also comprise suction means. The suction device can in particular be arranged close to the deflection unit and/or close to the surface to be treated in order to clean up ablation products, ie material detached from the surface due to the action of the laser. On the one hand, this reduces the subsequent cleaning costs required for the surface. On the other hand, contamination of the deflection unit or other optical elements is also prevented.

Furthermore, the device can also comprise a blower, which is situated opposite the suction device, so that the deflection unit or at least the laser beam is located between the blower and the suction device. This creates an air flow over the surface to ensure efficient product removal.

According to another aspect for better understanding of the present disclosure, a method for treating a polymer-coated surface, such as a painted aircraft component, includes the steps of:

- emitting pulsed laser light from a laser source configured to generate an infrared laser beam in the near-infrared range with a pulsed energy density of 0.01 J/cm2 to 50 J/cm2;

- directing the laser light as a laser beam onto the surface by means of a deflection unit; and

- moving the laser light along a certain path over the surface by means of a deflection unit.

In another implementation variant, the method can also include producing, by means of the deflection unit, on the surface of the aircraft component between laser points.

In yet another implementation variant, the method can also include the step of generating a laser spot on the surface, which is carried out by the deflection unit. Additionally, according to the method, the deflection unit can also include moving the laser points step-by-step along the path, wherein the temporally earlier laser point spatially overlaps the temporally following laser point. Alternatively or additionally, according to the method, the deflection unit may comprise moving the laser spots row by row along the path, wherein the temporally earlier laser spots of the first row are separated from the temporally following laser spots of the second row overlap in space.

In another implementation variant, the method can also include painting a region of the surface (of the aircraft component), wherein this region was previously treated with a laser. In other words, the previously performed method steps for the laser treatment of the surface (of the aircraft component) serve as a pretreatment of at least one specific region of the surface (of the aircraft component). The resulting surface properties in at least one specific region can provide very good adhesion for subsequent painting (of the aircraft component). This can be achieved on the one hand by cleaning the surface (removing dirt) and on the other hand by modifying the surface (ie activating the surface for subsequent painting).

Furthermore, the aspects and implementation variants described above can of course also be combined without being explicitly described. Each of the described implementation variants can therefore be seen as an alternative to each of these aspects, refinements and variants or to existing combinations thereof. The present disclosure is therefore not limited to individual configurations and to implementation variants in the described order or specific combinations of these aspects and implementation variants.

Description of drawings

A preferred embodiment of the invention is now explained in detail with the aid of a schematic drawing in which:

Figure 1 schematically shows a device for pre-treating the surface of an aircraft component;

Figure 2 schematically shows the different states during the processing of the surface of an aircraft component;

Figure 3 schematically shows the movement of the laser along a certain path; and

FIG. 4 schematically shows a flow chart of a method for pretreating the surface of an aircraft component.

Detailed ways

FIG. 1 schematically shows a device 100 for (pre)treating a surface 11 , in particular a surface 11 of an aircraft component 10 . Apparatus 100 includes a laser source 110 that emits pulsed laser light. Device 100 also includes a deflection unit 115 configured to direct the laser light of laser source 110 as laser beam 111 onto surface 11 of aircraft component 10 . Furthermore, the deflection unit 115 moves the laser beam 111 along the path 40 over the surface 11 of the aircraft component 10 (see FIGS. 2 and 3 ).

The deflection unit 115 can be fastened on the robot arm 150 of the device 100 . Robotic arm 150 can be configured here for carrying out movements relative to aircraft component 10 . In other words, the robotic arm 150 can move the deflection unit 115 relative to the aircraft component 10 so that the deflection unit 115 touches at least part of the surface 11 of the aircraft component 10 with the laser beam 111 without moving the aircraft component 10 .

Alternatively or additionally, it is also possible to move the aircraft component 10 . For example, aircraft components may be fastened at or mounted on bench 160 . The stage 160 may be configured to perform movement relative to the deflection unit 115 or the robot arm 150 . This increases the area over which the deflection unit 115 touches the surface 11 of the aircraft component 10 , for example the entire aircraft component surface 11 .

As a result of the relative movement between aircraft component 10 and deflection unit 115 , laser beam 111 can be aligned as optimally as possible on surface 11 of aircraft component 10 . For example, an aircraft component 10 typically includes fastening means, such as rivets 20 protruding from the surface 11 of the aircraft component. Likewise, depressions 15 or other structural changes can also be present in the otherwise smooth and/or planar surface 11 . The optimal orientation (optimum angle of incidence) of the laser beam 111 onto the surface 11 is, for example, in the range of around 90° (substantially perpendicular to the surface 11 ). By means of the table 160 and/or the robot arm 150 and/or the optical components of the deflection unit 115 it is also possible to direct the laser beam 111 in the region of the rivet 20 , the recess 15 or in the surface 11 in a different manner compared to the rest of the region. Optimum angles of incidence onto the surfaces 11 , 15 , 20 are found in other regions of the direction orientation.

The device 100 may also comprise an optical fiber line 111 arranged between the laser source 110 and the deflection unit 115 . The laser light generated by the laser source 110 can be guided to a deflection unit 115 via a fiber optic line 116 .

The laser source 110 is configured for generating an infrared laser beam 111 in the near infrared range. The laser source 110 can in particular generate a laser beam 111 with a wavelength of 1064 nm. Furthermore, the laser source 110 is configured to generate a laser beam 111 with a pulse energy density of 0.01 J/cm 2 to 50 J/cm 2 .

The deflection unit 115 can be configured to determine the path 40 on the surface of the aircraft component 10 such that the accumulated energy input into the surface 11 of the aircraft component 10 causes activation of the surface. Energy input onto/into the surface 11 in this way causes the surface 11 to heat up, thereby detaching surface material as schematically illustrated by evaporation/stripping 120 . The evaporation 120 of the surface material corresponds to the (pre)treatment of the surface 11 of the aircraft component 10 .

Removal products produced in evaporation 120 , ie material detached from surface 11 of aircraft component 10 due to the action of the laser, can be removed by suction device 170 . The suction device 170 can also be fastened to the robot arm 150 , for example. Here, the robot arm can be the same robot arm 150 to which the deflection unit 115 is fastened, or a separate robot arm (not shown).

Different treatments of the aircraft component surface 11 are shown in FIG. 2 . As shown in views a) and b) of FIG. 2 , dirt 30 may be present, for example, in the form of a multitude of particles adhering to the surface 11 . The deflection unit 115 can now guide the laser beam 111 along the path 40 substantially perpendicularly to the aircraft component 10 . The energy of the near-infrared laser beam 111 heats the particles 30 so that they vaporize ( 120 ) or at least detach from the surface 11 of the aircraft component 10 .

Alternatively or additionally, as shown in view c) of FIG. 2 , the near-infrared laser beam 111 can also be set so that it penetrates the top (outer) layer 12 on the aircraft component 10 and peels off the layer 12 (120 ). Viewed in the layer thickness direction, ie viewed from above in FIG. 2 , the layer 12 can also be only a part of a layer applied to the aircraft component 10 , for example a primer or a thinner layer of an already existing paint. partial area. This thinner portion 12 of the layer can be peeled off, for example, by the laser beam 111 heating the first paint (viewed from the outside) in the layer applied to the aircraft component 10 so that the first paint is removed from the applied The part of the layer that lies below it is detached. The part of the applied layer lying below the first paint remains on the aircraft component 10 . This makes it possible to achieve a very good activation of the surface 11 of the component 10 for subsequent treatment, such as the application of a further paint or a new paint. Of course, the particles 30 and the layer 12 can be removed from the surface by the laser beam 111 in the same working step.

The processing of the surface 11 of the aircraft component 10 is shown schematically in view d) of FIG. 2 , wherein a laser beam 111 produces surface structures 14 . For example, the heating 120 of the surface 11 introduced by the laser beam 111 may be performed to a certain depth. In particular by increasing the accumulated energy introduced into surface 11 and thus by heating 120 , the removed thickness of layer 12 can be varied. The surface structure 14 can be produced by removing different layer thicknesses in specific regions.

In particular, deflection unit 115 is configured to generate laser spots 111 - 1 to 111 - n on aircraft component surface 11 and to guide these laser spots 111 - 1 to 111 - n along path 40 , for example. This is shown in more detail in Figure 3, for example. Each laser spot 111 - 1 to 111 - n can have, for example, a diameter 112 of between 1 μm and 10.000 μm, for example a diameter 112 of 100 μm. The center point of the laser spot is now guided along the path 40, wherein the laser spot 111-1 to 111-n moves step by step. In this case, the temporally earlier laser spot 111 - 1 can spatially overlap with the temporally following laser spot 111 - 2 , ie have an overlapping surface 113 . Especially in the region of the overlapping surface 113 , the laser beam 111 strikes the surface 11 multiple times, so that more energy is introduced into the surface 11 . In other words, the cumulatively introduced energy into the surface 11 can be determined in a targeted manner by the size of the overlapping surface 113 , more precisely by the size of the step between two adjacent laser spots.

For example, the laser source 110 may generate the laser beam 111 as a pulsed laser beam 111 (of a frequency between 50 kHz and 10 MHz, preferably 150 kHz). The deflection unit 115 can move the laser spots 111 - 1 to 111 - n along the path 40 in such a way that the pulsed laser beam 111 hits each laser spot 111 - 1 to 111 - n with a certain frequency. For example, the laser beam 111 may hit the surface (ie hit the surface 11 ) 1 to 15 times, preferably between 2 and 5 times, for each laser spot 111 - 1 to 111 - n . By way of example only, the deflection unit 115 may be configured to move along the path 40 at between 100 mm/s and 1,000,000 mm/s, preferably between 500 mm/s and 500,000 mm/s and particularly preferably between The laser beam 111 is moved at a scanning speed between 500 mm/s and 500,000 mm/s. Therefore, in combination with the frequency of the laser beam 111 of the laser source 110, the number of hits of the laser beam 111 on the laser spots 111-1 to 111-n can be determined.

It is also shown in FIG. 3 that the deflection unit 115 can move the laser beam 111 along the path 40 line by line. Only three row paths 40 are shown by way of example in FIG. 3 . The course of path 40 shown here in an S-shape is merely exemplary. Of course, each row could start on the same side as shown on the left in Figure 3.

In this case, the deflection unit 115 can move the laser beam 111 in such a way that the temporally earlier laser spot 111-1 of the first row spatially overlaps the temporally following laser spot 111-m of the second row . The row spacing 41 together with the diameter 112 of each laser spot 111-1 to 111-n determines the overlapping area 51 between adjacent laser spots 111-1 to 111-n of two adjacent rows. In overlapping regions 51 generated line by line, the cumulative energy input into surface 11 of aircraft component 10 also increases and can be at least partially determined by line spacing 51 .

FIG. 4 shows an exemplary method for treating surface 11 . In the first step 200 , a pulsed laser with a pulse energy density of 0.01 J/cm 2 to 50 J/cm 2 is emitted by the laser source 110 . The laser source 110 is used in particular to generate an infrared laser beam in the near infrared range. In a further step 205 , the laser light is directed as laser beam 111 onto surface 11 (for example of aircraft component 10 ) by means of deflection unit 115 . The deflection unit 115 can also move the laser light along the path 40 over the surface 11 in a further step 210 .

Surface 11 is cleaned and/or activated by cumulative energy input into surface 11 by means of laser beam 111 . The regions of surface 11 treated in this way can then be (re)painted in step 220 . The pretreatment by means of the laser beam 111 greatly enhances the adhesion of the surface 11 to the (fresh) paint.

The examples and variants described above serve only to illustrate the invention. All examples, variants and individual details can be combined with one another in any desired way in order to form specific embodiments of the invention.

Claims (12)

1. A method for treating a surface (11) coated with a polymer and having particles and/or coatings, wherein the method comprises: emitting (200) pulsed laser light through a laser source (110) configured to generate an infrared laser beam (111) in the near-infrared range with a pulse energy density of 0.01J/cm2 to 50J/cm2; directing (205) said laser light as a laser beam (111) onto said surface (11) by means of a deflection unit (115); and moving (210) said laser light along a path (40) over said surface (11) by said deflection unit (115), Wherein the emission of the pulsed laser comprises setting the pulse energy density, so that the first particles and/or paint of the surface (11) facing the laser beam (111) absorb the pulsed infrared laser (111) and the resulting Part of the surface is detached, wherein the layer thickness of the polymer after the detachment is greater than or equal to 50%, preferably greater than or equal to 75%, particularly preferably greater than or equal to 90%, of the initial layer thickness of the polymer after the detachment. 2. The method according to claim 1, wherein the emission of the pulsed laser comprises generating the infrared laser beam (111) with a pulse length or pulse duration of 1 ns to 1000 ns. 3. The method according to claim 2, wherein the emission of the pulsed laser comprises setting the infrared laser beam (111) and/or the pulse energy density, so that the surface processed by the infrared laser beam The effective surface area of (11) obtains a microscopic increase of 5% or more, preferably 25% or more, and particularly preferably 50% or more. 4. The method of claim 1, further comprising: A diameter (112) between 1 μm and 10,000 μm, a diameter (112) preferably (112) between 10 μm and 1,000 μm and particularly preferably between 10 μm and 100 μm is produced on the surface (11) by the deflection unit (115) between laser points (111-1-111-n). 5. The method according to one of claims 1 to 4, further comprising, by the deflection unit (115): generating laser spots (111-1-111-n) on said surface (11); and moving the laser points (111-1-111-n) step by step along the path (40), wherein the laser point (111-1) earlier in time and the laser point (111 -2) overlap in space; and/or moving said laser spots (111-1-111-n) row by row along said path (40), wherein the temporally earlier laser spots (111-1) of the first row are different from the temporally earlier ones of the second row The following laser spots (111-m) overlap in space. 6. The method according to claim 5, wherein the line spacing (41) between two adjacent lines of the path (40) is between 0.001 mm and 10 mm, preferably between 0.01 mm and 1 mm and particularly preferably The ground is between 0.01mm and 0.1mm. 7. The method (100) according to claim 5 or 6, wherein the laser beam (111) is generated as pulses at a frequency between 50 kHz and 10 MHz, preferably at a frequency of 150 kHz, and wherein preferably the laser spots (111-1-111-n) are moved along the path (40) such that a pulsed laser beam (111) is directed at each laser spot (111-1-111-n ) 1 to 15 times, preferably between 2 and 5 times. 8. The method according to any one of claims 1 to 7, further comprising: A region of said surface (11) is painted (220), wherein said region has previously been treated by said laser. 9. The method according to one of claims 1 to 7, wherein the movement of the laser spot (111-1-111-n) comprises: a movement of the deflection unit (115) relative to the surface (11) movement and/or movement of said surface (11) relative to said deflection unit (115). 10. The method according to any one of claims 1 to 8, wherein moving the laser spot (111-1-111-n) comprises: along the path (40) at between 100mm/s and 1,000,000mm /s, preferably between 500 mm/s and 500,000 mm/s and particularly preferably between 500 mm/s and 500,000 mm/s to move the laser beam (111). 11. The method of any one of claims 1 to 10, further comprising: The removal product from said surface (11) is sucked by means of a suction device (170). 12. The method according to one of claims 1 to 11, wherein the surface (11) coated with polymer is a surface of an aircraft component.

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