Material-coating system tuned for removal via laser ablation

Abstract

To provide a material-coating system (200) having properties that are tuned for fast removal via laser ablation.SOLUTION: A material-coating system (200) includes a substrate (202), a laser-ablation layer (204) formed on the substrate (202), and a topcoat layer (206) formed on an upper surface of the laser-ablation layer (204). The topcoat layer (206) is at least partially transparent to laser light (400) in a predetermined wavelength. The laser-ablation layer (204) is tuned to absorb the laser light (400) in the predetermined wavelength such that application of the laser light (400) in the predetermined wavelength to the laser-ablation layer (204) causes the laser-ablation layer (204) and the topcoat layer (206) to collectively de-bond from the substrate (202).SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates generally to the field of material coatings, and more particularly to the removal of material coatings from solid surfaces. [Background technology]

[0002] The removal of material coatings, such as exterior decorative and non-decorative finishes, is commonly performed as part of maintenance, repair, and overhaul (MRO) operations on objects, such as buildings and vehicles (e.g., aircraft), that are coated with such material coatings. If an object is taken out of service due to MRO operations, the loss of revenue and operational readiness can be significant. For this reason, MRO technicians are highly motivated to remove material coatings as quickly as possible as part of the MRO operations in order to return the object to operational readiness again.

[0003] Conventional techniques for removing material coatings present various problems. For example, material coatings can be removed from an object by abrasion or sanding. Traditional hand sanding does not allow for sufficient control to avoid damage to the object's underlying substrate. When sanding is performed manually, the process is time-consuming and presents ergonomic challenges for the worker. Furthermore, workers must wear extensive personal protective equipment (PPE) to protect themselves from abrasive dust and other material particles generated during sanding, which increases the cost of traditional sanding.

[0004] As another example, material coatings can be removed from objects using chemical stripping. Traditional chemical stripping requires a long dwell time for the chemicals to effectively strip the material coating from the object's surface. Furthermore, traditional chemical stripping generates large amounts of hazardous waste that must be processed and disposed of in a carefully controlled process, increasing the cost of traditional chemical stripping. Workers also need to wear extensive PPE to protect themselves from the hazardous stripping chemicals and the chemical waste generated by traditional chemical stripping. Alternatively, environmentally sustainable stripping agents can be used to avoid some of the problems associated with the disposal of traditional stripping chemicals. However, these environmentally sustainable stripping agents require a longer dwell time compared to traditional stripping chemicals.

[0005] As yet another example, material coatings can be removed from objects using top-down laser material ablation. Top-down laser material ablation is performed by focusing a laser on the surface of the topmost material layer. Using current laser technology, each pass removes 25–50 micrometers of each layer. Laser material ablation requires multiple passes of the laser over the same area to remove each layer of material until the underlying substrate is exposed. While top-down laser material ablation offers many advantages over traditional sanding and chemical stripping, the multiple passes required to remove all layers still require significant time. In top-down laser material ablation, it is also possible to increase the amount of material removed per pass to speed up the overall process. For example, laser power can be increased or the laser depth of focus can be increased to remove more material per pass. However, adjusting the laser's operating parameters in this way can potentially result in laser damage to the underlying substrate during top-down laser material ablation. Furthermore, in some situations, adjusting the laser parameters may not be possible. Summary of the Invention

[0006] Disclosed are examples relating to a material coating system having tailored properties for rapid removal by laser ablation. In one example, the material coating system includes a substrate, a laser ablative layer formed on the substrate, and a topcoat layer formed on top of the laser ablative layer. The topcoat layer is at least partially transparent to laser light of a predetermined wavelength. The laser ablative layer is tailored to absorb the laser light of the predetermined wavelength, such that, upon irradiation of the laser ablative layer with the laser light of the predetermined wavelength, the laser ablative layer and the topcoat layer are peeled together from the substrate.

[0007] The above-described features, functions, and advantages may be realized individually in various embodiments and may be combined with one another in other embodiments, as will become apparent from the following description and drawings. [Brief explanation of the drawings]

[0008] [Figure 1] 1 illustrates an exemplary situation in which a layer of the material coating system of the present disclosure is removed from an aircraft by laser ablation. [Figure 2] 1 is a schematic diagram of an exemplary embodiment of a material coating system of the present disclosure; [Figure 3] FIG. 1 is a schematic diagram illustrating an exemplary laser ablation layer of a material coating system of the present disclosure, the laser ablation layer being doped with an additive configured to absorb laser light of a predetermined wavelength. [Figure 4] 3A-3C are schematic diagrams illustrating an example of laser ablation for removing layers of the material coating system of FIG. 2. [Figure 5]10A-10C are schematic diagrams illustrating other examples of laser ablation for removing layers of different material coating systems of the present disclosure. [Figure 6] 1 is a flowchart illustrating an exemplary method for manufacturing a material coating system of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0009] Conventional techniques for removing material coatings from objects have various problems. For example, traditional sanding and chemical stripping are time-consuming, laborious, and expensive processes, and workers must wear extensive personal protective equipment (PPE) to perform these processes. Top-down laser material removal offers several advantages over traditional sanding and chemical stripping. However, top-down laser material removal remains relatively time-consuming and laborious.

[0010] Laser ablation is an emerging technology in industrial hygiene and sustainability applications, particularly for removing material coatings from solid surfaces. Laser ablation is a process in which a laser generates a highly focused, intense beam of light and directs this beam toward the surface of the material to be ablated. The material undergoes various physical and chemical changes upon absorption of the laser energy. Depending on the laser parameters and the material, the absorbed laser energy can lead to a variety of processes, including heating, melting, evaporation, and ionization of the material. The absorbed energy can cause the material to either directly vaporize, forming a plume of particles, or undergo a phase change, such as melting or sublimation. Once the material undergoes a phase change, it can be detached from the target interface. Laser ablation offers a high degree of control and precision. By carefully adjusting the intensity, duration, and other characteristics of the laser light emitted by the laser, it is possible to selectively remove or modify the material while minimizing damage to the surrounding area. Laser ablation requires less time and effort than manual sanding and can be performed with shorter dwell times than chemical stripping, thereby avoiding the problems associated with traditional sanding and chemical stripping. Furthermore, laser ablation generates less waste than traditional sanding and chemical stripping. While top-down laser material removal offers many advantages over traditional sanding and chemical stripping, it remains a time-consuming process. This is because top-down laser material removal requires multiple passes of the laser to remove all layers of material from the target interface.

[0011] Therefore, when removing a material coating from an underlying substrate of an object, it is desirable to remove the material coating from the object more quickly than other conventional methods while protecting the underlying substrate. Accordingly, examples related to a material coating system with tailored properties for rapid removal by laser ablation are disclosed. In one example, the material coating system includes a substrate, a laser ablation layer formed on the substrate, and a topcoat layer formed on top of the laser ablation layer. The topcoat layer is at least partially transparent to laser light of a predetermined wavelength. The laser ablation layer is tailored to absorb the laser light of the predetermined wavelength, such that irradiating the laser ablation layer with the laser light of the predetermined wavelength causes the laser ablation layer and the topcoat layer to peel off together from the substrate.

[0012] Because the laser-ablation layer is disposed beneath at least the topcoat layer (and, in some embodiments, one or more additional intermediate layers), when the laser-ablation layer absorbs energy from the predetermined wavelength of laser light and ablates, the topcoat layer (and any intermediate layers) also separates from the underlying substrate. In this manner, multiple layers of the material coating system can be removed from the substrate with each laser pass. This allows layers of the material coating system to be removed at least two to three times faster than with top-down laser material ablation. Furthermore, the material coating system can also enjoy other benefits of laser ablation over traditional sanding and chemical stripping. For example, the use of a laser-ablation material coating system can reduce or eliminate the time, cost, and labor associated with PPE required for traditional sanding and chemical stripping, as well as similar burdens associated with hazardous waste disposal.

[0013] 1 illustrates an exemplary situation in which a layer of a material coating system of the present disclosure is removed from an aircraft by laser ablation. Periodically, aircraft 100 undergoes MRO operations, one of which is the removal and replacement of material coatings on the exterior surface 102 of aircraft 100. For example, the material coatings may include exterior decorative and non-decorative finishes. In some instances, the material coatings may deteriorate over time due to exposure to the environment during operation of aircraft 100, necessitating the removal and replacement of the material coating with an improved material coating. In other instances, aircraft 100 may be covered in a new paint job with a different color scheme or design.

[0014] In the illustrated example, the exterior surface 102 of the aircraft 100 is coated with a material coating system 200. The material coating system 200 is configured to be quickly and easily removed from the exterior surface 102 compared to other conventional methods. Specifically, the material coating system 200 includes a laser-ablation layer 204 (see FIG. 2 ) that is tuned to absorb predetermined wavelengths of laser light 106 emitted by a laser 104 for ablating each layer of the material coating system 200. The material coating system 200 is specially configured to form one or more additional layers, referred to herein as topcoat layers (e.g., topcoat layer 206 shown in FIG. 2 ), on the laser-ablation layer 204. When laser 104 emits laser light 106 of a predetermined wavelength and irradiates material coating system 200, laser ablation layer 204 absorbs energy from the laser light, causing laser ablation layer 204 and additional topcoat layer(s) 206 to peel off from underlying substrate 202 and be removed from substrate 202 by laser ablation.

[0015] Laser 104 may be configured to perform any suitable removal operation / routing by directing laser light at material coating system 200 to remove layers of material coating system 200 from aircraft 100. In one example, laser 104 performs a scanning removal routine, in which laser 104 scans and directs laser light at an area 108 of aircraft 100 in a back-and-forth motion. Additionally, laser 104 may pass over the same area 108 multiple times as part of the scanning routine to ensure that laser ablative layer 204 absorbs sufficient energy from laser light 106 to delaminate from substrate 202.

[0016] In some embodiments, the laser 104 is automatically controlled. For example, the laser 104 may be included in a robotic system that automatically performs laser ablation across the exterior surface 102 of the aircraft. In other embodiments, the laser 104 may be manually controlled by an operator. The laser 104 may take any suitable form.

[0017] Laser ablative layer 204 can be tuned to absorb energy from laser light of any suitable wavelength or range of wavelengths. In some examples, laser 104 may be configured to emit infrared or near-infrared light (e.g., a wavelength of approximately 1064 nanometers). As an example, a fiber laser can be used to ablate a layer of material coating system 200. Fiber lasers use ytterbium fiber as the lasing material. Fiber lasers are highly efficient and easy to maintain in the field. In other examples, material coating system 200 can be adapted for use with different types of lasers that emit laser light of different wavelengths, such as excimer lasers, CO2 lasers, fiber lasers, or other types of lasers that emit laser light of different wavelengths. The choice of laser is determined by the specific needs of the application, such as material properties, required precision, desired ablation depth, and acceptable thermal impact on surrounding materials. An appropriate laser can be selected to optimize the efficiency and effectiveness of laser ablation in MRO operations performed on aircraft 100.

[0018] 1 illustrates an exemplary situation in which a material coating system 200 coating an exterior surface 102 of an aircraft 100 is tuned to specific parameters of a laser 104 such that a layer of the material coating system 200 is removed from the aircraft 100 using laser ablation more quickly than other conventional methods. The concepts described herein for a material coating system configured for rapid removal by laser ablation are broadly applicable to applications other than aircraft. In other embodiments, the material coating system of the present disclosure can be applied to the surfaces of other types of vehicles or other structures, where similar benefits of rapid removal by laser ablation can be achieved.

[0019] FIG. 2 illustrates a schematic representation of an exemplary embodiment of a material coating system 200 of the present disclosure. Material coating system 200 includes a substrate 202, a laser ablation layer 204, and a topcoat layer 206. Substrate 202 forms the structural base layer of material coating system 200. In the example of aircraft 100 shown in FIG. 1, substrate 202 corresponds to exterior surface 102 of aircraft 100. Substrate 202 may include any suitable material. In some embodiments, substrate 202 includes a metal alloy, such as aluminum or titanium. In other embodiments, substrate 202 includes carbon fiber. Generally, once the layers of material coating system 200 are removed by laser ablation, substrate 202 remains in place as part of the underlying structure. In some embodiments, at least a portion of the substrate can be removed by laser ablation, as described in more detail below with reference to FIG. 5.

[0020] Laser ablation layer 204 is formed on top of substrate 202 of material coating system 200. Topcoat layer 206 is formed on top of laser ablation layer 204. Topcoat layer 206 is at least partially transparent to laser light of a predetermined wavelength, allowing the laser light to pass through topcoat layer 206 and reach laser ablation layer 204. The predetermined wavelength refers to the wavelength of laser light emitted from a laser and applied to material coating system 200 during laser ablation to remove a layer of material coating system 200 from substrate 202.

[0021] In some embodiments, the topcoat layer 206 can be completely transparent to laser light of a predetermined wavelength. For example, the topcoat layer 206 can be a visually transparent clearcoat applied as a protective finish to protect the underlying layers of the material coating system 200 from environmental exposure.

[0022] In some embodiments, the topcoat layer 206 may be partially transparent to laser light of a predetermined wavelength, allowing at least some of the laser light to pass through the topcoat layer 206 and reach the laser ablative layer 204. For example, the topcoat layer 206 may include some pigment that absorbs some of the laser light while allowing some of the laser light to pass through the topcoat layer 206 and reach the laser ablative layer 204. In some embodiments, the topcoat layer 206 is a visually opaque paint layer.

[0023] In some embodiments, the topcoat layer 206 can be at least partially transparent to light at other wavelengths in addition to the predetermined wavelength, hi some embodiments, the topcoat layer 206 can absorb at least a portion of light at other wavelengths in addition to the predetermined wavelength.

[0024] In some embodiments, multiple topcoat layers 206, 206', 206" can be formed on top of laser ablation layer 204. Each of multiple topcoat layers 206, 206', 206" can be at least partially transparent to laser light of a predetermined wavelength, allowing the laser light of the predetermined wavelength to pass through topcoat layer 206, 206', 206" and reach laser ablation layer 204. As an example, each of topcoat layers 206, 206', 206" can include a different color pigment that makes up the paint color scheme or particular design of aircraft 100 shown in FIG. 1. In other examples, each of the topcoat layers 206, 206′, 206″ can have different characteristics or functions. For example, the different topcoat layers can provide different types of protection from environmental elements, such as UV protection, heat protection, impact protection, or other types of protection. The material coating system 200 can include any suitable number and / or type of topcoat layers 206 formed on top of the laser ablation layer 204.

[0025] The laser ablative layer 204 is tuned to absorb laser light of a predetermined wavelength, such that when the laser ablative layer 204 is irradiated with laser light of the predetermined wavelength, the laser ablative layer 204 and topcoat layer 206 (including topcoat layers 206′, 206″, if present) are peeled off together from the substrate 202. In this manner, when a laser irradiates the material coating system 200 with laser light, multiple layers of the material coating system 200 can be removed from the substrate 202 in a single pass.

[0026] Laser ablative layer 204 can be tailored to absorb laser light of a predetermined wavelength in any suitable manner, hi some embodiments, laser ablative layer 204 may be selected or formulated to have material properties that absorb laser light of a predetermined wavelength.

[0027] In some other embodiments, the laser ablative layer 204 is doped with an additive tailored to absorb laser light of a predetermined wavelength. FIG. 3 schematically illustrates an example of a doped laser ablative layer 300 that can be included in the material coating system of the present disclosure. For example, the doped laser ablative layer 300 can correspond to the laser ablative layer 204 of the material coating system 200 illustrated in FIG. 2. The doped laser ablative layer 300 includes a base material 302 doped with an additive 304 tailored to absorb laser light of a predetermined wavelength. In some examples, the base material 302 itself has material properties tailored to absorb laser light of a predetermined wavelength. In other examples, the base material 302 is at least partially transparent to, or at least not absorbing, laser light of a predetermined wavelength.

[0028] The additive material 304 may include any suitable type of material tailored to absorb laser light of a predetermined wavelength. In some embodiments, the additive material 304 includes nano-sized particles. In some embodiments, the additive material 304 includes nanodiamonds tailored (e.g., formulated or selected) to absorb laser light of a predetermined wavelength. In other embodiments, the additive material 304 includes carbon nanotubes tailored (e.g., formulated or selected) to absorb laser light of a predetermined wavelength. In yet other embodiments, the additive material 304 includes gold nanoparticles tailored (e.g., formulated or selected) to absorb laser light of a predetermined wavelength. In yet other embodiments, the additive material 304 includes nanoclay tailored (e.g., formulated or selected) to absorb laser light of a predetermined wavelength. In still other embodiments, the additive material 304 includes micron-sized particles that are larger than the other nano-sized particles described above. For example, the micron-sized particles may include diamond, gold, clay, or other materials. The micron-sized particles are tailored (e.g., formulated or selected) to absorb laser light of a predetermined wavelength. In yet another embodiment, the additive 304 comprises graphene. In some embodiments, the laser ablation layer 300 is doped with multiple types of additives collectively tailored to absorb laser light of a predetermined wavelength. For example, the laser ablation layer 300 can include any combination of the additives described above and / or other suitable additives. These different types of additives have different physical properties and respond differently to different wavelengths of laser light. The type of additive doped into the laser ablation layer can be selected based on the predetermined wavelength of laser light and other factors. The nano-sized and / or micron-sized materials used in the material coating system can be applied sequentially in multiple different layers, combined to form "hybrid" layers, or both, as needed to achieve the desired properties for coating removal. Note that the particles of the additive 304 are shown schematically and may have shapes different from those shown. For example, some particles may be planar rather than spherical.

[0029] Referring again to FIG. 2 , in some embodiments, material coating system 200 may optionally further include a reflective layer 208 formed on the top surface of substrate 202, where reflective layer 208 is disposed between laser ablation layer 204 and substrate 202. In this embodiment, laser ablation layer 204 is formed on the top surface of reflective layer 208 rather than on the top surface of substrate 202. Reflective layer 208 is configured to reflect laser light of a predetermined wavelength. Reflective layer 208 has various advantages. For example, reflective layer 208 can protect substrate 202 from degradation by laser light, preventing damage to substrate 202 even after laser ablation. In some embodiments, reflective layer 208 can have heat-absorbing properties to protect substrate 202. In some embodiments, reflective layer 208 can include nanoclay to improve the heat-absorbing properties of substrate 202. As another example, reflective layer 208 reflects laser light of a predetermined wavelength and allows the laser light to pass through laser ablation layer 204 again. This allows laser ablative layer 204 to absorb more energy when the laser light reflects off reflective layer 208 and passes through laser ablative layer 204 a second time. This increased energy absorption allows laser ablative layer 204 and topcoat layer(s) 206 to peel from substrate 202 faster than if material coating system 200 did not include reflective layer 208.

[0030] In some embodiments, whether or not to include reflective layer 208 in material coating system 200 depends on the type of material comprising substrate 202. For example, if the substrate is formed of a single component, such as a metal alloy, the substrate is unlikely to require repair or partial repair during an MRO operation. In this case, the substrate does not need to be accessible during an MRO operation, and a reflective layer can be included in material coating system 200. On the other hand, the substrate may have known areas that require partial repair as part of an MRO operation. For example, such areas may include areas that are prone to corrosion. In this case, these areas can be addressed as part of the MRO operation by removing the reflective layer from material coating system 200. In some examples, these areas can be removed by laser ablation. Furthermore, in some examples, these areas may include a material tailored to absorb a predetermined wavelength of laser light, similar to laser ablation layer 204, so that the material, along with other layers of material coating system 200, can be removed from the target interface by laser ablation.

[0031] 4 illustrates a schematic diagram of an example of laser ablation for removing a layer of material coating system 200. At time T1, laser light 400 of a predetermined wavelength is emitted from laser 402 and enters material coating system 200. Laser light 400 passes through topcoat layer 206 and enters laser ablative layer 204. As laser light 400 passes through laser ablative layer 204, laser ablative layer 204 absorbs energy from laser light 400. Laser light 400 reflects off reflective layer 208, resulting in reflected laser light 406. Reflected laser light 406 is directed back through laser ablative layer 204, where additional energy is absorbed from reflected laser light 406. Reflected laser light 406 passes through topcoat layer 206 and exits material coating system 200. In some instances, the reflected laser light 406 may be heavily absorbed by the laser ablative layer 204 and only a small amount of the reflected laser light 406 may exit the material coating system 200 .

[0032] At time T2, the laser ablation layer 204 absorbs enough energy from the laser light 400 and the reflected laser light 406 to begin to peel and bubble up from the reflective layer 208 and substrate 202. Because the topcoat layer 206 remains bonded to the laser ablation layer 204, the topcoat layer 206 also begins to bubble up in a direction away from the reflective layer 208 and substrate 202.

[0033] At time T3, topcoat layer 206 and laser ablation layer 204 have collectively peeled and separated completely from reflective layer 208 and substrate 202. At this point, laser ablation is complete and topcoat layer 206 and laser ablation layer 204 have been removed collectively, leaving reflective layer 208 and substrate 202 intact in material coating system 200. Furthermore, MRO operations can continue, in which a new laser ablation layer and a new topcoat layer are formed on the remaining reflective layer 208 and substrate 202, and material coating system 200 can be refinished.

[0034] Laser ablation can be completed more quickly than other conventional coating removal methods because the laser ablation layer 204 and topcoat layer 206 can be peeled off together from the reflective layer 208 and substrate 202. This allows aircraft to return to service through MRO operations more quickly than with other conventional material coating removal methods, providing various benefits, including reduced aircraft operating costs.

[0035] FIG. 5 schematically illustrates another example of laser ablation for removing layers of a different material coating system 500 of the present disclosure. For example, material coating system 500 may correspond to material coating system 200 shown in FIG. 2. Material coating system 500 includes a fiber substrate 502, which includes a layer 502′ of fiber strands and a resin layer 502″. In some embodiments, fiber layer 502′ includes carbon fiber strands. In other embodiments, fiber layer 502′ includes glass fiber strands. In some embodiments, substrate 502 may include multiple fiber layers and a resin layer. In some examples, substrate 502 includes a glass fiber layer laminated on top of one or more carbon fiber layers (with a resin layer sandwiched therebetween). Material coating system 500 further includes a laser ablation layer 504 formed on top of substrate 502 and a topcoat layer 506 formed on top of laser ablation layer 504.

[0036] At time T1, laser light 508 of a predetermined wavelength is emitted from laser 510 and enters material coating system 500. Laser light 508 passes through topcoat layer 506 and enters laser ablative layer 504. The focal point or ablative plane 512 of laser 510 is set to a depth within the top layer of carbon fiber strands 502'. As laser light 508 passes through laser ablative layer 504, laser ablative layer 504 absorbs energy from the laser light 508. Laser light 508 continues into substrate 502 and reaches ablative plane 512. A resin layer 502" on top of substrate 502 is also tuned to absorb energy from the laser light 508 of a predetermined wavelength.

[0037] At time T2, the laser ablation layer 504 and the top resin layer 502" of the substrate 502 absorb enough energy from the laser light 508 to begin to peel and lift off from the top carbon fiber layer 502' of the substrate 502. Because the topcoat layer 506 remains bonded to the laser ablation layer 504, which in turn remains bonded to the top resin layer 502", the topcoat layer 506 also begins to lift off in a direction away from the substrate 502.

[0038] At time T3, topcoat layer 506, laser ablation layer 504, and top resin layer 502" have collectively completely peeled and separated from substrate 502. At this point, laser ablation is complete and topcoat layer 506, laser ablation layer 504, and top resin layer 502" are collectively removed, leaving fiber layer 502' and the remainder of substrate 502 intact in material coating system 500. Furthermore, MRO operations can continue, in which a new resin layer, a new laser ablation layer, and a new topcoat layer are applied to the remaining layers of substrate 502, and material coating system 500 can be refinished.

[0039] In the illustrated example, the resin layer 502″ is removed during laser ablation, exposing the fiber layer 502′ of the substrate. The resin layer 502″ may be removed from the substrate 502 for a variety of reasons. As one example, during operation, the material coating system may be exposed to the environment, necessitating replacement of the resin layer 502″. As another example, at the end of an aircraft's operational life, the aircraft may be dismantled and recycled or disposed of. Upon dismantling, the resin layer 502″ may be removed by laser ablation so that the material can be properly recycled or disposed of.

[0040] A flowchart of an exemplary method 600 for manufacturing a material coating system of the present disclosure is shown in Figure 6. For example, method 600 may be performed to manufacture material coating system 200 shown in Figure 2 or other material coating systems.

[0041] In some embodiments, method 600 can include forming a reflective layer on a top surface of a substrate of a material coating system, at 602. The reflective layer is configured to reflect laser light of a predetermined wavelength.

[0042] In some embodiments, method 600 may include, at 604, doping the laser-ablation layer with an additive configured to absorb laser light of a predetermined wavelength. In some embodiments, at 606, the additive may include nano-sized particles. In some embodiments, the nano-sized particles may include at least one of nanodiamonds, carbon nanotubes, gold nanoparticles, graphene, and nanoclay. In some embodiments, at 608, the additive may include micron-sized particles. In some embodiments, the micron-sized particles may include at least one of diamonds, gold, graphene, and clay. In some embodiments, at 610, the additive may include a mixture of nano-sized and micron-sized particles. In some embodiments, the laser-ablation layer may be doped with multiple types of additives collectively tailored to absorb laser light of a predetermined wavelength. For example, the laser-ablation layer may include any combination of the additives described above and / or other suitable additives. These different types of additives have different physical properties and respond differently to laser light of different wavelengths. The type of additive doped into the laser ablation layer can be selected based on the desired wavelength of the laser light and other factors. The nano- and / or micron-sized materials used in the coating system can be applied sequentially in multiple different layers, combined to form "hybrid" layers, or both, as needed to achieve the desired properties suitable for coating removal.

[0043] In other embodiments, the laser ablation layer may be tailored in a manner that does not involve doping the laser ablation layer with an additive. Alternatively, the material properties of the laser ablation layer itself may be selected / shaped to absorb laser light of a given wavelength.

[0044] At 612, the method 600 includes forming a laser ablation layer on top of the substrate. In some embodiments where the material coating system includes a reflective layer, at 614, the method 600 may include forming a laser ablation layer on top of the reflective layer.

[0045] At 616, the method 600 may include forming one or more topcoat layers on top of the laser ablation layer in a material coating system. In some embodiments, the topcoat layer may include a visually transparent clearcoat layer at 618. In some embodiments, the topcoat layer may include a visually opaque paint layer at 620.

[0046] The above-described method can be performed to fabricate a material coating system in which a laser-ablation layer is disposed beneath at least a topcoat layer (and, in some embodiments, one or more additional intermediate layers). When the laser-ablation layer absorbs energy from a predetermined wavelength of laser light and ablate, the topcoat layer (and any intermediate layers) also separates from the underlying substrate. In this manner, laser ablation can remove multiple layers of a material coating system from a substrate with each pass of the laser. This allows for faster removal of layers of a material coating system than other conventional methods.

[0047] In one example, a material coating system includes a substrate, a laser-ablation layer formed on the substrate, and a topcoat layer formed on top of the laser-ablation layer, the topcoat layer being at least partially transparent to laser light of a predetermined wavelength, and the laser-ablation layer being tuned to absorb the laser light of the predetermined wavelength, such that upon irradiation of the laser-ablation layer with the laser light of the predetermined wavelength, the laser-ablation layer and the topcoat layer are peeled together from the substrate. In this example and / or other examples, the laser-ablation layer may be doped with an additive tuned to absorb the laser light of the predetermined wavelength. In this example and / or other examples, the additive may include nano-sized particles. In this example and / or other examples, the nano-sized particles may include at least one of nanodiamonds, carbon nanotubes, gold nanoparticles, graphene, and nanoclay. In this example and / or other examples, the additive may include micron-sized particles. In this example and / or other examples, the additive may include a mixture of nano-sized particles and micron-sized particles. In this example and / or other examples, the topcoat layer may be a visually transparent clearcoat layer. In this example and / or other examples, the material coating system may further include a reflective layer formed between the laser ablation layer and the substrate, the reflective layer being configured to reflect the laser light of the predetermined wavelength. In this example and / or other examples, the substrate may include a metal alloy. In this example and / or other examples, the substrate may include a fiber layer and a resin layer, and the resin layer may be adjusted to absorb the laser light of the predetermined wavelength, such that irradiating the resin layer with the laser light of the predetermined wavelength causes the resin layer to peel from the fiber layer of the substrate.

[0048] In another example, a process for manufacturing a material coating system includes forming a laser-ablation layer on a top surface of a substrate and forming a topcoat layer on the top surface of the laser-ablation layer, the topcoat layer being at least partially transparent to laser light of a predetermined wavelength, the laser-ablation layer being tuned to absorb the laser light of the predetermined wavelength, such that upon irradiation of the laser-ablation layer with the laser light of the predetermined wavelength, the laser-ablation layer and the topcoat layer are peeled together from the substrate. In this and / or other examples, the process for manufacturing a material coating system may further include forming a reflective layer on a top surface of the substrate and forming the laser-ablation layer on top of the reflective layer. In this and / or other examples, the process for manufacturing a material coating system may further include doping the laser-ablation layer with an additive tuned to absorb laser light of the predetermined wavelength. In this and / or other examples, the additive may include nano-sized particles. In this example and / or other examples, the nano-sized particles may include at least one of nanodiamonds, carbon nanotubes, gold nanoparticles, graphene, and nanoclay. In this example and / or other examples, the additive may include micron-sized particles. In this example and / or other examples, the additive may include a mixture of nano-sized particles and micron-sized particles. In this example and / or other examples, the topcoat layer may be a visually transparent clearcoat layer. In this example and / or other examples, the substrate may include a fiber layer and a resin layer, and the resin layer may be adjusted to absorb the laser light of the predetermined wavelength, such that when the resin layer is irradiated with the laser light of the predetermined wavelength, the resin layer is peeled off from the fiber layer of the substrate.

[0049] In yet another example, a material coating system includes a substrate, a reflective layer formed on a top surface of the substrate, a laser ablation layer formed on the reflective layer, and a topcoat layer formed on a top surface of the laser ablation layer, wherein the topcoat layer is at least partially transparent to laser light of a predetermined wavelength, and the laser ablation layer is doped with an additive tailored to absorb the laser light of the predetermined wavelength, such that when the laser ablation layer is irradiated with the laser light of the predetermined wavelength, the laser ablation layer and the topcoat layer peel off together from the substrate, and the reflective layer is configured to reflect the laser light of the predetermined wavelength.

[0050] The structures and / or methods described in this disclosure are exemplary in nature. These specific embodiments or examples are susceptible to various modifications and should not be considered limiting. The specific routines or processes described herein may represent one or more of any number of processing methods. As such, the various operations shown and / or described may be performed in the order shown and / or described, in other orders, in parallel, or omitted. Similarly, the order of the processes described above may be changed.

[0051] The subject matter of the present disclosure includes all novel and non-obvious combinations and subcombinations of the various processes, systems, and configurations, and other features, functions, operations, and / or properties of the present disclosure, as well as all equivalents thereof.

[0052] The present disclosure also includes the following notes:

[0053] Appendix 1. A substrate (202), a laser ablation layer (204) formed on the substrate (202); a topcoat layer (206) formed on the upper surface of the laser ablation layer (204); the topcoat layer (206) is at least partially transparent to laser light (106) of a predetermined wavelength; The laser ablation layer (204) is adjusted to absorb the laser light (106) of the predetermined wavelength, such that when the laser ablation layer (204) is irradiated with the laser light (106) of the predetermined wavelength, the laser ablation layer (204) and the topcoat layer (206) are peeled off together from the substrate (202), in a material coating system (200).

[0054] Appendix 2. The material coating system (200) of Appendix 1, wherein the laser ablation layer (204) is doped with an additive (304) tuned to absorb the predetermined wavelength of laser light (106).

[0055] Clause 3. The material coating system (200) of clause 2, wherein the additive (304) comprises nano-sized particles.

[0056] Clause 4. The material coating system (200) of clause 3, wherein the nano-sized particles comprise at least one of nanodiamonds, carbon nanotubes, gold nanoparticles, graphene, and nanoclay.

[0057] Clause 5. The material coating system (200) of Clause 2, wherein the additive (304) comprises micron-sized particles.

[0058] Clause 6. The material coating system (200) of Clause 2, wherein the additive (304) comprises a mixture of nano-sized particles and micron-sized particles.

[0059] Appendix 7. The material coating system (200) of Appendix 1, wherein the topcoat layer (206) is a visually transparent clearcoat layer.

[0060] Appendix 8. The material coating system (200) of Appendix 1, further comprising a reflective layer (208) formed between the laser ablation layer (204) and the substrate (202) and configured to reflect the predetermined wavelength of laser light (106).

[0061] Clause 9. The material coating system (200) of clause 1, wherein the substrate (202) comprises a metal alloy.

[0062] Appendix 10. The material coating system (200) described in Appendix 1, wherein the substrate (502) includes a fiber layer (502') and a resin layer (502"), and the resin layer (502") is adjusted to absorb the laser light (508) of the predetermined wavelength, such that when the resin layer (502") is irradiated with the laser light (508) of the predetermined wavelength, the resin layer (502") is peeled off from the fiber layer (502') of the substrate (502).

[0063] Appendix 11. A process for manufacturing a material coating system (200), comprising: forming a laser ablation layer (204) on the upper surface of the substrate (202); forming a topcoat layer (206) on top of the laser ablation layer (204); the topcoat layer (206) is at least partially transparent to laser light (108) of a predetermined wavelength; The laser ablation layer (204) is tuned to absorb the laser light (108) of the predetermined wavelength, such that when the laser ablation layer (204) is irradiated with the laser light (108) of the predetermined wavelength, the laser ablation layer (204) and the topcoat layer (206) are peeled off together from the substrate (202).

[0064] Addendum 12. Forming a reflective layer (208) on the upper surface of the substrate (202); 12. The process for manufacturing a material coating system (200) of claim 11, further comprising forming the laser ablation layer (204) on top of the reflective layer (208).

[0065] Clause 13. A process for manufacturing a material coating system (200) according to clause 11, further comprising doping said laser ablation layer (204) with an additive (304) adapted to absorb said predetermined wavelength of laser light (108).

[0066] Clause 14. The process for manufacturing a material coating system (200) according to Clause 12, wherein the additive (304) comprises nano-sized particles.

[0067] Clause 15. The process for producing a material coating system (200) of clause 12, wherein the nano-sized particles comprise at least one of nanodiamonds, carbon nanotubes, gold nanoparticles, graphene, and nanoclay.

[0068] Clause 16. The process for manufacturing a material coating system (200) according to Clause 12, wherein the additive (304) comprises micron-sized particles.

[0069] Clause 17. The process for manufacturing a material coating system (200) according to Clause 12, wherein the additive (304) comprises a mixture of nano-sized particles and micron-sized particles.

[0070] Clause 18. The process for manufacturing a material coating system (200) according to clause 11, wherein the topcoat layer (206) is a visually transparent clearcoat layer.

[0071] Appendix 19. A process for manufacturing a material coating system (200) according to Appendix 11, wherein the substrate (502) comprises a fiber layer (502') and a resin layer (502"), and the resin layer (502") is adjusted to absorb the laser light (108) of the predetermined wavelength, such that when the resin layer (502") is irradiated with the laser light (108) of the predetermined wavelength, the resin layer (502") is peeled off from the fiber layer (502') of the substrate (502).

[0072] Appendix 20. A substrate (202), a reflective layer (208) formed on the upper surface of the substrate (202); a laser ablation layer (204) formed on the reflective layer (208); a topcoat layer (206) formed on the upper surface of the laser ablation layer (204); the topcoat layer (206) is at least partially transparent to laser light (108) of a predetermined wavelength; The laser ablation layer (204) is doped with an additive (304) adjusted to absorb the laser light (108) of the predetermined wavelength, so that when the laser ablation layer (204) is irradiated with the laser light (108) of the predetermined wavelength, the laser ablation layer (204) and the topcoat layer (206) are peeled off together from the substrate (202); The reflective layer (208) is configured to reflect the predetermined wavelength of laser light (108). [Explanation of symbols]

[0073] 100 aircraft 102 External Surface 104 Laser 106 Laser Light 108 areas 200 Material Coating System 202 Base material 204 Laser ablation layer 206 Topcoat layer 208 Reflective layer 300 doped laser ablation layer 302 Base Material 304 Additives 400 Laser Light 402 Laser 404 Laser ablation layer 406 Reflected laser light 500 Material Coating System 502 Base material 502' fiber layer 502” resin layer 504 Laser ablation layer 506 Topcoat layer 508 Laser Light 510 Laser 512 Ablation surface

Claims

1. A substrate; a laser ablation layer formed on the substrate; a topcoat layer formed on the upper surface of the laser ablation layer, the topcoat layer is at least partially transparent to laser light of a predetermined wavelength; The laser ablation layer is adjusted to absorb the laser light of the predetermined wavelength, such that when the laser ablation layer is irradiated with the laser light of the predetermined wavelength, the laser ablation layer and the topcoat layer are peeled off together from the substrate.

2. 10. The material coating system of claim 1, wherein the laser ablation layer is doped with an additive tailored to absorb the predetermined wavelength of laser light.

3. The material coating system of claim 2 , wherein the additive comprises nano-sized particles.

4. 4. The material coating system of claim 3, wherein the nano-sized particles comprise at least one of nanodiamonds, carbon nanotubes, gold nanoparticles, graphene, and nanoclay.

5. The material coating system of claim 2 , wherein the additive comprises micron-sized particles.

6. The material coating system of claim 2 , wherein the additive comprises a mixture of nano-sized particles and micron-sized particles.

7. The material coating system of claim 1 , wherein the topcoat layer is a visually transparent clearcoat layer.

8. The material coating system of claim 1 , further comprising a reflective layer formed between the laser ablation layer and the substrate, the reflective layer configured to reflect the predetermined wavelength of laser light.

9. The material coating system of claim 1 , wherein the substrate comprises a metal alloy.

10. 2. The material coating system of claim 1, wherein the substrate includes a fiber layer and a resin layer, and the resin layer is adjusted to absorb the laser light of the predetermined wavelength, such that when the laser light of the predetermined wavelength is irradiated onto the resin layer, the resin layer is peeled off from the fiber layer of the substrate.

11. 1. A process for manufacturing a material coating system, comprising: forming a laser ablation layer on an upper surface of the substrate; forming a topcoat layer on top of the laser ablation layer; the topcoat layer is at least partially transparent to laser light of a predetermined wavelength; The laser ablation layer is tuned to absorb the laser light of the predetermined wavelength, such that when the laser ablation layer is irradiated with the laser light of the predetermined wavelength, the laser ablation layer and the topcoat layer are peeled off together from the substrate.

12. forming a reflective layer on an upper surface of the substrate; 12. The process for manufacturing a material coating system of claim 11, further comprising: forming the laser ablation layer on top of the reflective layer.

13. 12. The process for manufacturing a material coating system of claim 11, further comprising doping said laser ablative layer with an additive tailored to absorb said predetermined wavelength of laser light.

14. The process for manufacturing a material coating system of claim 12 , wherein the additive comprises nano-sized particles.

15. 13. The process for manufacturing a material coating system of claim 12, wherein the nano-sized particles comprise at least one of nanodiamonds, carbon nanotubes, gold nanoparticles, graphene, and nanoclay.

16. The process for manufacturing a material coating system of claim 12 , wherein the additive comprises micron-sized particles.

17. 13. The process for manufacturing a material coating system of claim 12, wherein the additive comprises a mixture of nano-sized particles and micron-sized particles.

18. 12. The process for manufacturing a material coating system of claim 11, wherein the topcoat layer is a visually transparent clearcoat layer.

19. 12. The process for manufacturing a material coating system of claim 11, wherein the substrate includes a fiber layer and a resin layer, and the resin layer is adjusted to absorb the laser light of the predetermined wavelength, such that when the resin layer is irradiated with the laser light of the predetermined wavelength, the resin layer is peeled off from the fiber layer of the substrate.

20. A substrate; a reflective layer formed on the upper surface of the substrate; a laser ablation layer formed on the reflective layer; a topcoat layer formed on the upper surface of the laser ablation layer, the topcoat layer is at least partially transparent to laser light of a predetermined wavelength; the laser ablation layer is doped with an additive adjusted to absorb the laser light of the predetermined wavelength, whereby when the laser ablation layer is irradiated with the laser light of the predetermined wavelength, the laser ablation layer and the top coat layer are peeled off together from the substrate; The reflective layer is configured to reflect laser light of the predetermined wavelength.

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