COATING TO IMPROVE PERFORMANCE AND SERVICE LIFE IN PLASTIC PROCESSING APPLICATIONS.

Abstract

An improved coating used in plastics processing applications, comprising a first layer system with at least one corrosion-resistant layer; a second layer system with at least one abrasion-resistant layer; and a transition layer disposed between the first and second layers. The coating is resistant to both abrasion and corrosion, while maintaining ductility and impact resistance.

Description

COATING TO IMPROVE PERFORMANCE AND LIFESPAN IN PLASTIC PROCESSING APPLICATIONS Lfr / cnn / Lznz / e / YiAi Field of Invention The present invention relates to coatings, in particular to coatings used in plastic processing applications. Background of the Invention Plastic processing applications such as injection molding or extrusion involve several stages where metal tools can come into physical contact with the plastic. This contact can subject the tool, for example, injection molds, to combined corrosive and abrasive attack. The corrosive media induced by plastics can originate from various plastic components, such as softeners, colorants, and free hydrochloric acid. Simultaneously, the increasing interest in using fiberglass-reinforced plastics in various plastic processing applications, such as injection molding for automotive parts, has led to more abrasive tool wear. Fiberglass-reinforced plastics with a fiberglass content greater than 30% are extremely abrasive and reduce tool life.These types of polymers can be visualized as a multi-indenter carried by a fluid that causes wear through micro-cutting and micro-plowing, as well as the impact of solid particles through plastic deformation and material removal. Figure 1 illustrates a scanning electron microscope (SEM) cross-sectional image of such glass fiber reinforced plastics. The movement of glass fibers across the tool surface can cause scratches, which deteriorate the surface quality of the mold and subsequently lead to plastic defects. This necessitates maintenance, such as polishing the tool surface, or can result in complete tool failure. To protect tools against combined corrosive and abrasive attacks during plastic processing applications, various coatings and deposition techniques have been tested, such as high-speed oxygenated fuel (HVOF), hard chrome or nickel-phosphorus metallic coatings, physical vapor deposition (PVD) or chemical vapor deposition (CVD) titanium, aluminum, and other layers of - 2 carbide or nitride. PVD-deposited ceramic coatings are of great interest because they can theoretically exhibit both high hardness and chemical inertness. Therefore, ceramic coatings should, in theory, separate the substrate from the aggressive environment and thus protect it. However, it is well documented that most of the time the use of ceramic coatings on many types of steel only marginally improves, if at all, the corrosion resistance of steel substrates in corrosive environments. As shown in Figure 2, a PVD coating applied to a substrate includes a plurality of defects, such as holes.These defects provide rapid diffusion pathways for corrosive media, chloride ions, to reach the substrate and create a galvanic cell at the coating-substrate interface. This is because ceramic coatings are electrochemically more stable than most substrate materials (e.g., steels). The corrosion rate at the interface can be very high since the coating, acting as a cathode, has a large surface area compared to the very small area of ​​the exposed substrate, acting as the anode. Consequently, the coating can no longer protect the substrate. Corrosion propagates laterally along the coating-substrate interface, leading to partial or delamination of the coating and the appearance of corrosion wear on the substrate. Ultimately, this will result in complete coating failure, characterized by total or near-total degradation of the coating and corrosion of the substrate. Furthermore, abrasive attack and cracking of brittle ceramic coatings due to high loads or impacts during application can further accelerate the coating's corrosive failure. Therefore, in the processing of fiberglass-reinforced plastics with very high abrasion resistance, high corrosion resistance, as well as a certain level of ductility and impact resistance, are simultaneously required. Summary of the Invention. The object of the present invention is to overcome one or more difficulties related to the prior art. In particular, the object of the present invention is to provide a coating for the effective and reliable protection of tools, especially tools used in plastics processing, against combined corrosive and abrasive attacks. Lfr / cnn / Lznz / e / YiAi The following is a simplified summary to provide a basic understanding of the modalities described in this document. This description is not a comprehensive overview, nor is it intended to identify key or critical elements. Its sole purpose is to introduce some concepts in a simplified manner as a prelude to the detailed description presented later. According to a first aspect of the invention, a coating is provided for a substrate. The coating includes: a first layer comprising at least one corrosion-resistant layer; a second layer comprising at least one abrasion-resistant layer; and a transition layer provided between the first and second layers, wherein the first layer is deposited closer to the substrate than the second layer. Since the first layer is designed to comprise at least one corrosion-resistant layer (hereafter referred to as the corrosion-resistant layer), the first layer is to be understood as a layering system consisting of one or more layers.Similarly, since the second layer is designed to include at least one abrasion-resistant layer (hereafter referred to as the abrasion-resistant layer), the second layer should be understood as a layering system consisting of one or more layers. The transition layer should also be understood as a layering system consisting of one or more layers; for example, it may consist of one or more gradient layers. Therefore, the aforementioned inventive coating should also be understood as comprising: - a first coating layer system consisting of one or more layers, wherein said first coating system comprises at least one corrosion-resistant layer; - a second coating layer system consisting of one or more layers, wherein said second layer system comprises at least one abrasion-resistant layer (further referred to as the abrasion-resistant layer); and - a layer transition system consisting of one or more layers, where said layer transition system is arranged between the first layer system and the second layer system, the one or more layers in the transition system may be, for example, gradient layers, but may also be non-gradient layers, as well as a combination of gradient and non-gradient layers. Lfr / cnn / Lznz / e / YiAi -4In another example of the first aspect, the first layer is part of a first layer system arranged closer to the substrate than the second layer, wherein said first layer system comprises one or more corrosion-resistant layers, wherein at least one corrosion-resistant layer is an AlCrO layer. In another example of the first aspect, the second layer is part of a second layer system disposed further away from the substrate than the first layer system, wherein said second layer system comprises one or more abrasion-resistant layers, wherein at least one abrasion-resistant layer is a CrON layer. In another example of the first aspect, the transition layer is part of a layer transition system, where said layer transition system comprises one or more transition layers, where at least one transition layer is a CrON layer. In another example of the first aspect, the layer transition system comprises a Cr2Ü3 layer. In another example of the first aspect, the second layer system comprises at least one CrN layer. In another example of the first aspect, the second layer system comprises at least one CrO layer. In another example of the first aspect, the second layer system comprises at least one CrxOs layer arranged as the outermost layer. In another example of the first aspect, the first layering system comprises at least one AlCrN layer arranged between the substrate and the AlCrO layer. In another example of the first aspect, at least one adhesion layer is provided between the substrate and the first layer or between the substrate and the first layer system. In another example of the first aspect, the at least one adhesion layer is a CrN layer. In another example of the first aspect, the first layer or first layer system includes one or more layers of the following materials: aluminum chromium oxide (AlCrO), aluminum chromium oxytrite (AlCrON), chromium oxides (CrOx), and chromium (III) oxide (CrzOs). In another example of the first aspect, the second layer or second layer system includes one or more layers of the following materials: chromium (Cr) , chromium nitride (CrN) , chromium oxynitrid (CrON) , chromium oxides (CrOx) , and chromium (III) oxide (Cr2O3) . Lfr / cnn / Lznz / e / YiAi In another example of the first aspect, the second layer system has a hardness between 29 GPa and 33 GPa. In another example of the first aspect, the first layer or first layer system is a multilayer part that includes at least one of AlCrO, AlCrON, CrOx, and Cr2O3. In another example of the first aspect, the second layer or second layer system is a multilayer part that includes at least one of Cr, CrN, CrON, CrOxy Cr2O3. In a second aspect of the present invention, a substrate having a coating as previously described is disclosed, wherein the surface where the coating is deposited is made of a material including a ferrous metal. In another example of the second aspect, the surface where the coating is deposited is made of a material that includes steel or is made of a steel-type material. In a third aspect of the present invention, a method for coating a substrate is provided. The method includes providing a substrate; coating the substrate with multiple layers of corrosion-resistant materials; coating the multiple layers of corrosion-resistant materials with at least one transition layer; and coating the at least one transition layer with multiple layers of abrasion-resistant materials. Other features and aspects may become evident from the following detailed description, the Figures and the claims. Lfr / cnn / Lznz / e / YiAi Brief Description of the Figures Figure 1 illustrates a cross-sectional image of the prior art of glass fiber reinforced plastics. Figure 2 illustrates a substrate coated with prior art showing corrosion and corrosion failure. Figure 3 schematically illustrates an example of an inventive coating 105 deposited on a substrate surface 110 according to an embodiment of the present invention, wherein: the second layer system 140 is a multilayer film comprising layers, for example, of the type Cr, CrN, CrON, CrOxo, CrO3; the first layer system 120 is a multilayer film comprising layers, for example, of the type AlCrO, AlCrON, Cr2O3, the transition layer or layers of - 6 transition 130 are arranged between the first layer system 120 and the second layer system 140. Figure 4 illustrates the results of abrasion resistance tests, showing a comparison of the wear depth evolution under the same conditions using substrates coated with prior art AlTiN and AlCrN coatings, as well as using a new multilayer coating according to an embodiment of the present invention. In this graph, none of the coatings have yet exhibited coating failure. Figure 5 illustrates the results of corrosion resistance tests showing a comparison of the occurrence of corrosion and, in some cases, even coating failure produced under the same conditions using substrates coated with comparative prior art coatings of the AlTiN and AlCrN type, as well as using a new multilayer coating according to an embodiment of the present invention. Throughout the Figures and the detailed description, unless otherwise specified, the same drawing reference numbers will be used to refer to the same elements, features, and structures. The relative size and representation of these elements may be exaggerated for clarity, illustration, and convenience. Lfr / cnn / Lznz / e / YiAi Detailed Description of the Invention The following are examples incorporating one or more embodiments of the present invention and, where applicable, are illustrated in the accompanying Figures. These described and / or illustrated examples are not intended to be limiting. For example, one or more aspects of one embodiment of the present invention may be used in other embodiments and even on other types of substrates (e.g., tools, components, or devices). Therefore, what is described herein is an example of a multilayer coating architecture with material selections that exhibit high abrasion resistance and high corrosion resistance, as well as ductility and impact resistance. Corrosive attack typically occurs at an interface between a coating and a substrate. Consequently, a corrosion-resistant layer or a corrosion-resistant portion of a multilayer coating can be provided at this interface. With reference to Figure 3, an example is illustrated.- 7 Example of a corrosion-resistant part 100 (e.g., part of a component, tool, or device coated with a coating comprising a corrosion-resistant part according to the present invention. In this example, a corrosion- and abrasion-resistant coating 105 is applied to a substrate 110. The substrate 110 may be a tool, such as an injection mold, with a ferrous metal surface, such as steel or cast iron. However, the coating 105 may also be applied to non-ferrous metal surfaces. The coating 105 includes a first layer system 120 comprising at least one corrosion-resistant layer, thereby exhibiting corrosion-resistant properties. For example, the first layer system 120 may include one or more layers of aluminum chromium oxide (AlCrO), aluminum chromium oxynitride (AlCrON), chromium oxide (CrOx), and / or chromium(III) oxide (Cr2O3).These corrosion-resistant oxide and oxide layers act as an insulator to mitigate external electron diffusion and also as a barrier to the internal diffusion of corrosive ions from the environment. These layers prevent or slow the diffusion of corrosive ions. Furthermore, a second layer system 140 can be provided on top of the first layer system 120. The second layer system 140 can be deposited as a single layer or as a multi-layer, including one or more abrasion-resistant layers, thereby exhibiting abrasion-resistant properties. This second layer system 140 protects the substrate 110 against abrasive wear, and the at least one corrosion-resistant layer forming the first layer system 120 protects the substrate against corrosive wear. In this way, the inventive coating 105 provides the substrate 110 with good corrosion-resistant properties, as well as resistance to abrasive wear and mechanical loads during application. In particular, the second layer system 120 may include one or more of the following layers to form a multilayer: chromium (Cr) , chromium nitride (CrN) , chromium oxynitride (CrON) , chromium oxides (CrOx) , and / or chromium (III) oxide (Cr2O3). The resulting coating can have a high hardness of 31 ± 2 GPa, where the coating can be deposited exhibiting a multilayer structure comprising individual layers with respective thicknesses in the micrometer and / or nanometer range. This structure exhibits greater ductility and crack deviation, in addition to Lfr / cnn / Lznz / e / YiAi - 8. Be highly resistant to abrasion and tolerant of mechanical loads. As shown in Figure 3, at least one transition layer 130 can be provided between the first layer 120 and the second layer 130 to mitigate delamination of the corrosion- and abrasion-resistant parts. Since the layers have different crystalline structures and lattice parameters, as well as chemical compositions, a precise transition (comprising one or more transition layers) can be important, for example, to improve cohesion within the coating 105 by increasing the adhesion between the first layer system 120 and the second layer system 140. Therefore, tests were conducted to evaluate the abrasion resistance properties of the inventive example coatings (novel multilayer coatings) compared to prior art comparative coatings against glass fiber reinforced plastics. With reference to Figure 4, coated steel substrates were tested against polyamide with 50% glass fiber content in a dry slip test with a perpendicular load of 100 N over a distance of 120 km. Figure 4 thus illustrates the wear depth of a coating according to the modality described in Figure 3 compared to conventional (prior art) abrasion-resistant PVD coatings of the aluminum chromium nitride (AlCrN) and titanium aluminum nitride (TiAlN) types. The superior performance of the inventive coatings in terms of abrasion resistance is clearly evident. In order to evaluate the corrosion resistance of the inventive coatings according to the modality illustrated in Figure 3 compared to the same conventional abrasion-resistant PVD coatings (from the prior art) referred to previously, a neutral salt spray test (NSST) was carried out. The coatings were applied to a 1.2842 cold-rolled steel substrate with 0.4 to %Cr. The low Cr content allows for a higher galvanic potential between the substrate (steel) and the CR-containing coatings and, therefore, a higher degree and rate of corrosion during the NSST. As can be seen in Figure 5, the conventional AlCrN and AlTiN coatings exhibited severe pitting corrosion in many areas. This pitting corrosion propagated rapidly over the next few days. By day 6, oxidized iron from the substrate covered almost the entire surface of the coating. Lfr / cnn / Lznz / e / YiAi Conversely, the inventive coatings, according to the example modality described in Figure 3, showed very few minor pitting spots on the first day. Furthermore, this remained stable throughout the sixth day, with no further corrosion points or propagation observed. A number of examples of inventive coatings and materials that can be used as layers in inventive coatings have been described above. However, it is understood that various modifications are possible. For example, suitable results can be achieved if the described elements are combined in a different way and / or replaced or supplemented with other elements or their equivalents. Accordingly, other implementations are considered to be included within the scope of the following claims. A preferred embodiment of the present invention relates to a coating comprising: a first layer system, a second layer system, and at least one transition layer, wherein: - the first layer system comprises at least one AlCrN layer and preferably also at least one AlCrO layer as corrosion-resistant layers, - the second layer system comprises at least one CrON layer and preferably also at least one CrN layer and / or one CrO layer, and - a layer transition system formed by one or more transition layers arranged between the first layer system and the second layer system, wherein the layer transition system comprises at least one Cr2O3 transition layer and / or at least one CrON transition layer, wherein the transition layers can be deposited as gradient layers or as non-gradient layers or as a combination of gradient and non-gradient layers. Each of the embodiments and preferred embodiments of the present invention described above may further include one or more adhesion layers disposed between the substrate and the first layer system to improve the adhesion of the first layer system to the substrate, preferably a CrN layer may be used as an adhesion layer. This adhesion layer, or, if more than one adhesion layer is provided, the total thickness of the adhesion layers is preferably not greater than 1 micrometer. However, the layer thickness of the adhesion layer or the sum of the adhesion layers may also be greater than 1 micrometer, but preferably not greater than 1.5 micrometers. Each of the previously referred to embodiments and the preferred embodiments of the present invention may include a Cr2O3 layer as Lfr / cnn / Lznz / e / YiAi - The top layer of the coating, which acts as the outermost layer of the second coating system to improve performance, especially with regard to abrasive wear resistance. This outermost layer is preferably applied with a layer thickness of 1 micrometer or more. However, the layer thickness of this outermost layer can also be less than 1 micrometer, but preferably not less than 0.5 micrometers. The thickness of the first layer system is preferably greater than 1 micrometer, more preferably greater than 2 micrometers. However, the layer thickness of the first layer system may also be less than 1 micrometer, but preferably not less than 0.5 micrometers. The thickness of the second layer system is preferably greater than 2 micrometers, more preferably greater than 2.5 micrometers. However, the layer thickness of the first layer system may also be less than 2 micrometers, but preferably not less than 1.5 micrometers. The thickness of the second layer system is preferably greater than the thickness of the first layer. The coatings according to the present invention are preferably deposited with a total coating thickness between 1 and 30 micrometers, more preferably between 2.5 micrometers and 20 micrometers. However, this preferred coating thickness range should not be construed as a limitation of the invention. In general, the total coating thickness, as well as the thickness of individual layers or the layer system, can be selected depending on the tooling application or the substrate use. The coatings according to the present invention are particularly suitable for improving the performance and increasing the service life of injection molds used for manufacturing parts made of plastic materials, for example polyester materials. In order to show in more detail the improvements achieved with inventive coatings, another example will be described as a demonstrative coating below: The demonstrative coating was deposited onto injection molding tool surfaces (e.g., injection molds or injection mold parts) to be in contact with the workpiece material using physical vapor deposition (PVD) techniques of the cathodic arc reactive evaporation type. During coating deposition, the Cr and / or AlCr targets were arc-evaporated in a coating chamber containing gas. Lfr / cnn / Lznz / e / YiAi - 11 nitrogen and / or oxygen gas as a reactant gas. In this particular demonstration, AlCr targets with an atomic percent composition of 70 to 30% Al and 30 to 1% Cr were selected. This demonstrative coating was deposited comprising a CrN adhesion layer deposited directly onto the surface of the injection molding tool to be coated, subsequently a first layer system (also called a corrosion layer system in the context of the present invention) comprising an AlCrN layer and an AlCrO layer was deposited onto the adhesion layer, subsequently a transition layer system (transition layer system = two or more transition layers) comprising a Cr2O3 transition layer and a CrON transition layer was deposited onto the first layer system, subsequently,A second layer system (also called an abrasive layer system in the context of the present invention) comprising a plurality of layers deposited alternately as layer sequences, each layer sequence comprising CrN layers, CrON layers, and CrO layers, and further comprising a Cr2U3 layer as the outermost layer, was deposited in the transition layer system. For some actual application tests, as shown, for example, in Figure 6, the demonstrative coating was deposited with a total coating thickness between 6 and 8 micrometers. Inventive coatings can be applied to a previously nitrided substrate, for example, on previously nitrided surfaces of injection molding tools. The inventive coatings are preferably deposited by any PVD method, for example, arc PVD or sputtering PVD, preferably maintaining a substrate temperature between 250°C and 450°C. However, this preferred substrate temperature during coating should not be understood as a limitation of the invention. Preferably, the deposition of nitride layers (e.g., CrN and AlCrN) is carried out by applying a DC substrate bias to the substrate, while the deposition of oxygen-containing layers (e.g., oxide or oxytrite layers such as CrO, Cr2O3 and CrON) is preferably carried out by applying a bipolar bias. Preferably, for the deposition of layers comprising nitrogen and / or oxygen that are subsequently deposited one on top of the other, the oxygen, nitrogen flux and oxygen flux entering Lfr / cnn / Lznz / e / YiAi - 12 in the coating chamber are gradually increased and / or decreased to produce a sequence of layers or simply layers deposited on top of each other, for example, to deposit first a CrN layer, then a CrON layer and then a CrO layer, subsequently the Cr targets can be initially evaporated maintaining a certain nitrogen flow entering the coating chamber to deposit the CrN layer, subsequently an oxygen flow can be introduced and gradually increased in the coating chamber, while the nitrogen flow can be maintained or gradually decreased for the deposition of the CrON layer, and finally the nitrogen flow can be gradually reduced to 0 sccm, while the oxygen flow is maintained or gradually increased or reduced to a certain oxygen flow for the deposition of the CrO layer.A similar process can be carried out in reverse to deposit an inverse sequence of layers, for example CrO CrON CrN. Inventive coatings are suitable for coating any type of substrate material. In the case of applications in the field of plastic forming processes (e.g., injection molding and extrusion), the substrate materials are predominantly different types of steel. During the deposition of oxygen-containing layers, particularly oxide layers, the inventors recommend using oxygen flow rates adjusted for the coating device being used and the coating conditions, such as the type of target material and the amount of target material being evaporated. It is recommended to find an oxygen flow rate range in which the mechanical properties and the density of the coating morphology are suitable for the intended application. Excessive oxygen content in the coating chamber can lead to poor mechanical properties and a low-density morphology of the deposited oxygen-containing layer. During the deposition of certain inventive coatings comprising, for example, a layer sequence of the type CrN 5 CrNO 5 CrO, the oxygen flux was intensified and the nitrogen flux was reduced. For example, the oxygen flux was increased from 200 sccm to 600 sccm for the deposition of the CrNO and CrO layers, and the nitrogen flux was reduced from 1100 sccm to 100 sccm for the deposition of the CrN and CrNO layers. For the deposition of reverse sequences, for example CrO 5 CrNO Lfr / cnn / Lznz / e / YiAi - 13CrN the oxygen and nitrogen fluxes also increased and decreased, but inversely. Figure 6 shows the results obtained by injection molding (application tests under real conditions) of four injection molds (identified as Mold 1, Mold 2, Mold 3, and Mold 4 in Figure 6) coated with an inventive coating deposited in the same manner as the previously described demonstrative coating, and one injection mold coated with a prior art coating of the AlTiN type. These results allow quantifying the improvement achieved by the present invention by comparing the number of injection molding shots (parts produced; in this case, electrical switches) performed with molds coated with AlTiN and molds coated according to the present invention. As shown in the graph in Figure 6, with the mold coated with the prior art AlTiN coating, only 40,000 to 50,000 shots could be achieved before the coated mold could no longer operate (the average service life was approximately 50,000 shots). With molds coated according to the present invention, the improvement was considerably high, even exceeding 400% in one case, and these molds coated with the inventive coatings continued to function. The workpiece material used in these tests was unsaturated polyester with 30% glass fiber; the parts produced were electrical switches. Therefore, a coating deposited on a substrate has been disclosed in the present invention, the coating comprising a first layer or a first layer system comprising at least one layer of corrosion-resistant material; a second layer or a second layer system comprising at least one layer of abrasion-resistant material; and a transition layer disposed between the first layer and the second layer, wherein the first layer or first layer system is deposited closer to the substrate than the second layer system or second layer. This coating has an advantage compared to coatings that have only one abrasion-resistant part, for example, a multilayer structure of the type . . . CrN / CrON / CrN / CrON. . . where the previously mentioned abrasion-resistant part only provides good abrasion resistance, but poor corrosion resistance. Lfr / cnn / Lznz / e / YiAi 14Thus, including a corrosion-resistant component closer to the substrate, for example, at least one AlCrO layer, improves corrosion resistance because the AlCrO layer acts as a corrosion barrier. Including an AlCrN layer between the AlCrO layer and the substrate further enhances the corrosion barrier effect while improving the coating's adhesion to the substrate. Similarly, including an adhesion layer, such as a CrN layer, can significantly improve the adhesion of the corrosion-resistant component to the substrate. The transition layers improve the cohesion of the coating by enhancing the adhesion between the corrosion-resistant part and the abrasion-resistant part of the coating. The use of an outer Cr20s layer increases the performance of the coating, especially for applications that include the processing of plastic materials, for example, injection molding, because AlCrO reduces the tendency to adhere to plastic materials during workpiece processing (due to the effect of lower chemical affinity with plastic materials). The first layer or a first layer system preferably includes one or more layers of the following materials: aluminum chromium oxide (AlCrO), aluminum chromium oxynitride (AlCrON), chromium oxide (CrOx) and chromium (III) oxide (C^Os). The second layer or second layer system preferably includes one or more layers of the following materials: chromium (Cr), chromium nitride (CrN), chromium oxytrite (CrON), chromium oxides (CrOx), and chromium (III) oxide (Cr2O3). Preferably, the second layer or the second layer system has a hardness between 29 GPa and 33 GPa as measured by using known nano-indentation techniques. The first layer or first layer system may be in a multilayer part modality that includes at least one of AlCrO, AlCrON, CrOxy Cr2O3. The second layer or second layer system may be in a multilayered part mode, including at least one of Cr, CrN, CrON, CrOxy Cr2O3. The first layer or first layer system is designed to isolate the substrate from external electron diffusions and internal diffusions of corrosive ions from an environment. Lfr / cnn / Lznz / e / YiAi - 15The transition layer or layer transition system is designed to mitigate delamination between the first layer and the second layer. The chemical composition of the first layer or first layer system is different from the chemical composition of the second layer or second layer system. In one modality, the crystal structures and lattice parameters of the first layer or first layer system may be different from the crystal structures and lattice parameters of the second layer or second layer system. The present invention also relates to a method of coating a substrate, comprising: provide a substrate; apply a corrosion-resistant multilayer part to the substrate; Apply at least one transition layer to the corrosion-resistant multilayer part; and apply an abrasion-resistant multilayer part to the at least one transition layer. The substrate coated with a coating according to the present invention may include a ferrous metal surface on which the coating is deposited. In an additional embodiment, the corrosion-resistant multilayer portion comprises at least one of the following materials: AlCrO, AlCrON, CrOxy CrzOs and / or the abrasion-resistant multilayer portion comprises at least one of the following materials: Cr, CrN, CrON, CrOxy Cr2O3. In particular, a coating according to the present invention can be used in plastic processing applications. The coating is resistant to both abrasion and corrosion, while maintaining ductility and impact resistance. Furthermore, according to a preferred embodiment of a coating according to the present invention, the inventive coating is deposited on a substrate surface characterized by comprising: a first layer comprising at least one layer of corrosion-resistant material; a second layer comprising at least one layer of abrasion-resistant material; and Lfr / cnn / Lznz / e / YiAi - 16a transition layer disposed between the first layer and the second layer, wherein the first layer is deposited closer to the substrate than the second layer, wherein the first layer is part of a first layer system deposited closer to the substrate than the second layer, wherein said first layer system comprises one or more corrosion-resistant layers, wherein a corrosion-resistant layer is preferably an AlCrO layer. Preferably the second layer is part of a second layer system deposited further away from the substrate than the first layer system, said second layer system comprising one or more abrasion-resistant layers, an abrasion-resistant layer being a CrON layer. Preferably, the transition layer is part of a layer transition system, said layer transition system comprising one or more transition layers, a transition layer being a CrON layer. Preferably, the layer transition system comprises a Cr2Os layer. Preferably, the second layer system comprises at least one CrN layer and / or at least one CrO layer. Preferably, the second layer system comprises at least one Cr203 layer deposited as the outermost layer. Preferably, when the first layering system comprises at least one AlCrO layer, at least one AlCrN layer is deposited between the substrate and the AlCrO layer. Preferably, at least one adhesion layer is deposited between the substrate and the first layer or between the substrate and the first layer system. Preferably, at least one adhesion layer is a CrN layer. Lfr / cnn / Lznz / e / YiAi

Claims

1. A coating deposited on a substrate surface wherein said coating is characterized in that it comprises: a first layer comprising at least one layer of corrosion-resistant material; a second layer comprising at least one layer of abrasion-resistant material; and a transition layer disposed between the first layer and the second layer, wherein the first layer is deposited closer to the substrate than the second layer.

2. The coating according to claim 1, wherein the first layer is part of a first layer system disposed closer to the substrate than the second layer, wherein said first layer system comprises one or more corrosion-resistant layers, wherein at least one corrosion-resistant layer is an AlCrO layer.

3. The coating according to claim 1 or 2, wherein the second layer is part of a second layer system deposited further from the substrate than the first layer system, wherein said second layer system comprises one or more abrasion-resistant layers, wherein at least one abrasion-resistant layer is a CrON layer.

4. The coating according to any of claims 1 to 3, wherein the transition layer is part of a layer transition system, wherein said layer transition system comprises one or more transition layers, wherein at least one transition layer is a CrON layer. Lfr / cnn / Lznz / e / YiAi 5. The coating according to any of the previously referred claims, wherein the layer transition system comprises a Cr2O3 layer.

6. The coating according to any of claims 3 to 5, wherein the second layer system comprises at least one CrN layer.

7. The coating according to any of claims 3 to 6, wherein the second layer system comprises at least one CrO layer.

8. The coating according to any of claims 3 to 7, wherein the second layer system comprises at least one Cr2O3 layer disposed as the outermost layer.

9. The coating according to any of claims 3 to 8, wherein the first layer system comprises at least one AlCrN layer disposed between the substrate and the AlCrO layer.

10. The coating according to any of claims 1 to 9, wherein at least one adhesive layer is deposited between the substrate and the first layer or between the substrate and the first layer system.

11. The coating according to claim 10, wherein the at least one bonding layer is a CrN layer.

12. The coating according to any one of claims 1 to 11, wherein the first layer or the first coating system includes one or more layers of the following materials: aluminum chromium oxide (AlCrO), aluminum chromium oxytrite (AlCrON), chromium oxides (CrOx), and chromium(III) oxide (Cr2O3). Lfr / cnn / Lznz / e / YiAi 13. The coating according to any of claims 1 to 12, wherein the second layer or the second layer system includes one or more layers of the following materials: chromium (Cr) , chromium nitride (CrN) , chromium oxynitride (CrON) , chromium oxides (CrOx) and chromium (III) oxide (Cr2Os) .

14. The coating of claims 1 to 13, wherein the second layer or the second system has a hardness between 29 GPa and 33 GPa.

15. The coating according to any of claims 1 to 14, wherein the first layer or first layer system is a multilayer part comprising at least one of AlCrO, AlCrON, CrOx and Cr2O3.

16. The coating according to any of claims 1 to 15, wherein the second layer or second layer system is a multilayer part comprising at least one of Cr, CrN, CrON, CrOx and Cr2O3.

17. A substrate having a coating according to any one of claims 1 to 16, wherein the surface on which the coating is deposited is made of a material including a ferrous metal.

18. A substrate having a coating according to any one of claims 1 to 16, wherein the surface on which the coating is deposited is made of a material including steel or is made of a steel-type material.