WO2016079148A1

WO2016079148A1 - Blade material

Info

Publication number: WO2016079148A1
Application number: PCT/EP2015/076874
Authority: WO
Inventors: Alexiou ATHANASSIOS
Original assignee: Athanassios Alexiou
Priority date: 2014-11-18
Filing date: 2015-11-17
Publication date: 2016-05-26
Also published as: DE102014016983A1; EP3221492A1; EP3221492B1

Abstract

The present invention relates to a blade having at least one cutting edge, wherein the blade comprises at least in the region of the cutting edge a multi-layer material with at least five layers, and wherein metal layers and metal ceramic layers are arranged alternately in the multi-layer material and at least one metal layer and at least one adjacent metal ceramic layer have respectively at least one metal element in common.

Description

blade material

The present invention relates to a blade or a multilayer material for a blade or blade.

In recent years, cutters made of technical ceramics whose function and shape have been retained for a longer time due to the material, have become more and more widespread and are used, for example. Also used for the production of knives, where they substitute the usual steel knives in many areas. At the same time, but also e.g. Cutting razor blades, which are still made of steel in the core, coated with thin layers of ceramic or synthetic diamond (DLC - Diamond Like Carbon) or similar layers to increase their edge retention. This is described, for example, in US Pat. No. 5,056,227 A, US Pat. No. 6,684,513 Bl and WO 2013010072 Al. Also blades made of e.g. amorphous metals, the production of which is technically possible and generally extremely difficult with only a few special alloys, are becoming increasingly common, e.g. used in medical technology (scalpels, etc.).

The usually longer service life, ie the increased edge retention, ceramic and amorphous cutting materials, is known to result from the lack of ductility compared to metals and the higher hardness of the materials used. At the same time, however, lower fracture toughness and breaking strength of ceramic or amorphous materials mean that cutting edge geometries have to be adapted to the values of the abovementioned mechanical parameters or similar important material parameters, resulting in, for example, only coarser cutting radii and blunt wedge and ground angles at the tip of the blades can be realized than those that are possible when cutting with a substrate / core of metal or a metal alloy. As an example, razor blades made of steel should be mentioned, which have the highest degree of cutting ability (cf., for example, US Pat. No. 5,056,227 A, US Pat. No. 6,684,513 B1, WO 2013010072 A1), with radii at the tip of the blade in the range of a few nanometers (cf., for example, US Pat. No. 5,056,227 A, WO 2013010072 Al), at the same time lower edge retention compared to ceramic cutting. It is therefore an object of the present invention to provide an improved cutting edge or an improved cutting material, which is optimized both with regard to the highest possible edge retention, and as far as the greatest possible cutting ability. This object is achieved, inter alia, by a multilayer material having at least three layers, wherein in the multilayer material metal layers (including unalloyed or alloyed metallic layers understood - eg alloyed steels, unalloyed or alloyed titanium (eg Ti6A17Nb) etc - hereinafter, whether alloyed or unalloyed, simply referred to as metal layers) and hard material layers (ceramic or amorphous layers) are arranged alternately. The present invention relates, inter alia, to a cutting edge made of such a multilayer material or a blade having a cutting edge, the blade having such a multilayer material at least in the area of the cutting edge. It should be emphasized at this point that this multilayer material is not a subsequently applied superficial coating or superficial treatment of a blade or cutting edge previously produced from a single substrate, as known, for example, from WO 2013010072 A1. Instead, this multilayer material is the actual material of the cutting edge, that is to say the material from which the cutting edge itself consists and from which at least part of the cutting edge geometry is produced. The cutting edge produced from this material can then be coated as superficially as is usual with steel blades.

The present invention is based, inter alia, on the idea of providing a corrosion-resistant multi-layer or multilayer material comprising nano-, micro- (layers on the cutting edge) and / or macro lamellae (surface layer (s), carrier material) that performs differently than homogeneous blade materials its heterogeneous structure has advantageous mechanical properties. Blades or cutting edges made of this material can be used in everyday use, among other things, for chipless cutting or shearing of relatively soft materials (eg biological tissue, textile lines, etc.), but also for cutting production processes (eg according to DIN 8580) of materials low hardness (eg wood, plastic and especially hair, etc.) are used. Due to their material composition and nanostructure, the cutting edges according to the invention are characterized not only by an increased edge retention in relation to cutting edges the uncoated, single-coated or multi-coated steels usually used for this purpose (as are known, for example, from US Pat. Nos. 5,056,227, 6,684,513 B1 and WO 2013010072 A1), but also by increased cutting ability compared to cutting edges made of technical ceramics (cf., for example, US Pat. No. 3,543,402 A , US 5,077,901 A and US 7,140,113 B2).

Both effects, the increased edge retention against metal blades and the improved cutting ability compared to ceramic solutions, are made possible by the fact that the actual cutting edge consists of a lamellar multi-layer nanomaterial.

The present invention makes it possible to realize cutting with higher edge retention than conventional razor blades and higher cutting ability than ceramics. This results in a combination of cutting ability and edge retention, as they did not exist before and how it has been technically not yet realized. For this purpose, the properties of metals with the properties of ceramics, or amorphous layers, in the form of two-dimensional lamellae are so often technically combined together that optimum cutting edge geometries at the tip of the blade, e.g. those of razor blades made of steel, can be realized. At the same time the mechanical properties of these are exceeded.

Conventional composite materials such as hard metals, cermets or so-called MMCs (metal matrix composite materials) are known to consist of a binder metal phase (in hard metal, for example cobalt, iron or nickel, in cermets the aforementioned but also eg molybdenum), in the hard materials (usually particles of eg tungsten carbide). or titanium / tantalum carbide, but also diamond etc.) or fibers (of eg silicon carbide, in which MMCs) are embedded. These materials are used, for example, in material processing because they allow a significantly higher processing speed and have a significantly longer service life than comparable steel tools. However, these composites, despite their outstanding macro- and mesoscopic mechanical qualities for the production of cutting, have significant disadvantages. For example, the particles previously used for hard metals and cermets have particle sizes in the range of 0.2 μηι to over 50 μηι. This is hindering the production of the finest micro- and nanoscopic sclline geometry, which must be realized with wedge-shaped structures down to the single-digit nanometer range. For example, in the case of MMCs, ceramic fibers improve the tensile strength and other important mechanical parameters of the material class; However, cutting can not be realized in this way, since the fibers are also a hindrance in the production of nanostructures.

Worth mentioning for the sake of completeness, are still cutting glass, as proposed for example in US 4,702,004 A and US 3,831,466 A. Filigree structures in the area of the cutting edge, however, such as e.g. For use as a razor blade, or cutting for knives, are not useful to realize the glass material due to the usually even worse mechanical characteristics (fracture toughness and fracture resistance) compared to steel and most high-performance technical ceramics, as can be easily understood. Moreover, the use of glass cutters in connection with use as e.g. Blades in the field of personal care, associated with a higher risk of injury to the user, or knives due to the rapid fragmentation not really recommended. It is therefore understandable that even the solutions proposed several decades ago in US 4,702,004 A and US 3,831,466 A could not prevail or ever establish themselves.

Although steel cutting edges reinforced with superficial amorphous or ceramic layers (eg WO 2013010072 A1) can have a higher edge retention compared to uncoated steel blades, they still have the distinct disadvantage that the metallic substrate gives way to the cutting edge after a long dynamic or static load and mechanically becomes unstable, whereby the hard outer coating breaks and therefore can not maintain the edge retention of the blade alone. A function preservation of the cutting edge geometry of steel blades can be extended by high-quality coatings to approximately ten times the service life, compared to steel blades without coating. The plastic deformability of the metallic substrate, which is initially an advantage in the production of filigree cutting geometry, is However, with appropriate use of the blade but also responsible for the continuous destruction of the same.

In contrast to the known solutions described above, the multilayer material of the present invention effectively combines metal (any metallic alloys or elemental metals) and hard material (ceramic or amorphous material) so as to cause breakage of the blade caused by external cutting forces and counteracted in the long term. The present invention has about 100 times the resistance to external dynamic loads compared to uncoated steel blades. At the same time, it is also possible to reinforce the blades described here additionally with superficial layers (ceramic or amorphous), as is already done with blades made of steel, whereby the service life is further increased significantly.

Dislocations - also known as one-dimensional lattice defects - in the metallic layers and resulting dislocation movements, can not pass through this layer of material through the ceramic / amorphous layers to other layers. That the mechanisms that are responsible for the permanent plastic hardening of a metallic cutting edge and that lead to long-term lamination of lattice defects in the metallic material to break the blade are suppressed in the long term by the phases of hard material between them. Accordingly, the individual metallic layers are completely spatially isolated from each other by the one-dimensional layers of hard material therebetween.

Also, martensitic steels contain the finest carbides, but these are uniformly distributed throughout the volume in the form of compact particle aggregates, with diameters in the range of a few nanometers and above. Although this increases the hardness of the material and allows very fine cutting to be made therefrom, however, these carbides do not effectively block the movement of lattice defects in the volume, and the blade can plastically deform. However, if the blade contains too many carbides, the material breaks easily (as is the case with ceramic materials) because it is then brittle. Cracking and crack propagation, which normally results in breakage and failure of blade function in ceramic and amorphous materials, are both effectively suppressed by the present invention. Normally, in the case of ceramic or amorphous materials, fatigue or signs of wear are manifested by the fact that microcracks form in the material after long-term dynamic or static loading with sufficiently high intensity that can suddenly spread under certain stress conditions in the ceramic material. A plastic deformation as with the metals is not possible here. These cracks are then responsible for the rapid break, ie the malfunction of the material used. The multilayer material of the present invention, however, is able to stop this crack propagation over several layers due to its lamellar or layered structure of alternating metallic, ceramic or amorphous layers and thereby prevent the complete malfunction of the material. The adjacent metallic layers not only retard the propagation of cracks within the layer in which the crack has formed by reducing stress at the cracking site at the boundary layers to adjacent metal layers, but also prevent the cracks from spreading to the next hard layers. The microcrack within a layer also remains in this layer. This is possible because cracking causes local dislocation movements at the interfaces to the metal. These are not only responsible for a reduction of the stresses in the hard material layers, but at the same time cause local solidification in the metallic layers (limit volume metal / hard material), whereby the crack propagation within the layer can be delayed or even stopped. The function of this hard material layer is thereby retained. Again, the individual layers of hard material are separated by two-dimensional metal layers, spatially isolated from each other.

In addition, the entire material reacts elastically to bending forces due to the laminar bond and therefore does not break as easily as, for example, ceramic blades. And another key advantage that results from the lamellar multi-texture structure is the ability to adjust the hardness of the blade within material constraints by varying the layer thickness ratios and choosing the materials of the layers. This goes hand in hand with it It is also possible to set other micro- and macro-mechanical properties significantly depending on the location, such as fracture toughness and flexural strength. These mechanical characteristics are anisotropic and, of course, also depend on the orientation of the lamellar system in the measuring arrangement.

In principle, the mechanical and physical properties of the multilayer material can be influenced not only by the choice of the materials of the metal or hard material layers, but also by the layer thicknesses, the layer thickness ratios, and by adjusting the course of the layer thicknesses over the cross section of the cutting edge.

However, if possible, the following considerations should play a role:

Due to the fact that as small as possible and stable geometric structures must be realized at the top of the cutting edge or the cutting edge, at this point preferably the layer thicknesses should be relatively small, i. in the range of a few nanometers. However, this is not absolutely necessary, but depends on the particular application and the desired cutting geometry.

At the same time, adjacent layers should preferably be connected to each other as best as possible in order to prevent the layers from flaking off one another. A suitable choice of the adjacent materials is advantageous for the stability and the functionality of the multilayer material.

Also, individual layers within the multi-layer material, especially at the blade tip, preferably should not be too thick so as not to sacrifice the aforementioned advantages of nano- and microstructuring. Because if the layer thicknesses are too large, the macro-mechanical properties of the individual layers become more evident again, which again may prove to be a disadvantage if, for example, Cracks or plastic deformations can become stronger again. Also, thicker layers, due to internal stress, tend to peel off the rest, which should be advantageously avoided.

The manufacturing process makes the realization of such layers economical Limits. So should not unnecessarily many materials have to come together in combination. Also, not too many layers should be created, otherwise the entire process can be very expensive. At the same time, the total layer thickness can not be chosen arbitrarily, which goes without saying, as this can be associated with an enormous amount of time in the production.

The present invention relates inter alia to a blade with a cutting edge, the blade having a multilayer material with at least five layers at least in the area of the cutting edge, wherein metal layers and hard material layers are arranged alternately in the multilayer material. In this case, at least one metal layer and at least one adjacent hard material layer preferably have at least one metal element in common (with a metal-ceramic layer), or the metal layers adjoining an amorphous layer (eg DLC) form bonds to one of the main constituents of the amorphous layer (eg titanium to DLC, wherein titanium forms a native carbide at the boundary layer to the amorphous carbon). This has the advantage that adjacent metal and hard material layers are particularly well connected to the blade cutting edge, which can effectively prevent chipping of the layers from each other. Also, atomic layers can be used to promote adhesion between metal and hard coatings, if necessary. Although these intermediate layers are part of the layer system, they are only considered as adhesive layers and not as essential layers of the layer system if the sequence of successive layers is considered. Also, several hard or soft solder layers may be within the material, e.g. in order to be able to connect / combine later separately layer systems. These layers, too, are part of the layer system, but are taken into consideration only as solder layers or connecting layers when considering the sequence of successive layers, not as essential layers of the multilayer system.

Preferably, the multi-layer material has at least seven, more preferably at least nine, and most preferably at least 11 layers. It goes without saying that the present invention is not limited to an odd total number of layers. Rather, four, six, eight or ten layers can also be provided. The cutting edge preferably has a cutting edge which is formed by a first and a second cutting surface, which include a wedge angle. The first cutting surface includes a first angle with the layers of the multilayer material and the second cutting surface subtends a second angle with the layers of the multilayer material. Preferably, the first and / or second angle is at least 1 °, more preferably at least 3 °, even more preferably at least 5 °, and most preferably at least 10 °. The two angles should not exceed 80 ° and preferably 70 °. Preferably, the first and / or second angle is in the range between 3 ° and 33 °; more preferably in the range between 5 ° and 25 °. In this case, the layers of the multilayer material preferably run parallel to one another. If this is not the case, the aforementioned included angles between cutting surface (s) and layers are preferably valid for all layers of the multilayer material.

In the case of a cutting tool, one usually speaks of rake surface and free surface. In this case, the cutting edge of the blade preferably has a rake face and an open face. The rake surface and / or the flank (Figures 7 and 8) preferably include an angle of at least 1 °, more preferably at least 5 °, and most preferably at least 10 ° with the layers of the multilayer material. In this case, the layers of the multilayer material preferably run parallel to one another. If this is not the case, then the aforementioned included angles between rake surface and layers are preferably valid for all layers of the multilayer material.

The thickness of the individual layers is preferably constant. According to a preferred alternative, the thickness of the individual layers of the multilayer material increases from the cutting edge towards the edge of the blade. The thickness of a few layers, eg only the surface layer (s) / carrier layer (s) or the thickness of all layers can increase. Exceptions to this are soldering or bonding layers which are added to the layer system only later and which, for example, are not produced under the same manufacturing process conditions as a large part of the layer system, and adhesive layers which are generally only a few atomic layers thick. The thickness of the individual layers is preferably between 0.5 nm and 1 mm, more preferably between 1 nm and 800 μηι, even more preferably between 1.5 nm and 600 μπι and particularly preferably between 2 nm and 500 μιη. In principle, layer thicknesses from a few atomic layers to a few millimeters are conceivable. The thickness of the individual layers can furthermore preferably be between 0.5 nm and 1 μm, more preferably between 1 nm and 800 nm, even more preferably between 1.5 nm and 600 nm and particularly preferably between 2 nm and 500 nm.

Preferably, the thickness of at least three central layers in the region of the cutting edge is less than 150 nm, more preferably less than 100 nm. Additionally or alternatively, the thickness of at least two outer layers is preferably greater than 150 nm and particularly preferably greater than 200 nm.

The cutting edge may have one or more additional outer, ie superficial, hard material layers. If these layer (s) are metal ceramics, at least one metal-ceramic layer contains at least one of the metals contained in the multilayer material. It is then particularly preferred that the innermost of the outer ceramic layers, i. that metal ceramic which is in direct contact with the remaining layers of the multilayer material contains at least one of the metals contained in the multilayer material. An additional DLC layer can also be provided in addition or as an alternative to the outer hard material layers, if necessary with suitable adhesion promoters (for example based on tungsten, titanium, etc.), which particularly preferably forms the outermost layer.

One or more of the metal layers preferably comprise one or a combination of the following materials: titanium (Ti), iron (Fe), tantalum (Ta), zirconium (Zr), vanadium (V), niobium (Nb), aluminum (AI) , Hafnium (Hf), chromium (Cr), tungsten (W), boron (B) and optionally other additives / alloying elements (eg silicon, molybdenum, carbon, nitrogen, etc.) and all possible mixtures or alloys of these elements in any mixing ratios (eg TiAl, ZrAl, HfAl, CrAl, TiAlZr, TiAlV, AlSi, ZrHf, TiZr, FeCr and all other possible combinations). One or more of the hard material layers preferably comprise one or a combination of the following materials: carbides, nitrides, carbonitrides, borides, oxynitrides, oxicarbides, oxicarbonitrides, oxides, boronitrides, boron carbides, diborides, boron carbonitrides, oxiborides, oxibornitrides, oxiborcarbides and oxiborcarbonitrides of the abovementioned metals (such as WC, TiC, TiN, TiCN, TiBN, TiB _2, Tibon, TiBCN, TiAlN, TiAlCN, TiCON, TiZrN, TiZrCN, Zr0 _2, ZrN, NbC, Nb ₂ C, HfC, A1 ₂ 0 _3, CrN , CrCN, AlSiN, and all other possible combinations), if they are metal-ceramic layers.

In order to achieve the best possible connection of the alternating layers with one another, it is preferred that metal-ceramic layers contain a metal or alloying element of their neighboring layers to a considerable extent and, accordingly, such as native nitride, carbide or oxide can merge seamlessly into the adjacent metallic layers. For example, Ti Ti layers adjacent to TiAlC or TiAlN layers would be a possible combination of materials. Another would be e.g. Chrome steel on chromium nitride layers. The exception to this is, as already mentioned, brazing or bonding layers made of soft or brazing material. For amorphous layers, it is preferable that mating adhesive layers provide a strong bond to the adjacent metal layers, or that they more preferably merge into the adjacent metal (e.g., DLC (= carbon) via TiC to Ti).

The materials or the material composition of the metallic or hard material layers can therefore of course also vary from layer to layer and also within one and the same layer - this can hardly be avoided, depending on the type of production and the thickness of the individual layers - and need not, but can also be constant over the course of the shift system. For example, it is possible to consider less hard metal-ceramic layers for the outer regions of the layer system than for the inner layers or vice versa. In addition, due to their production, metal-ceramic layers contain arbitrary concentration gradients of the aforementioned metals as well as non-metals, but may therefore also be targeted from eg a nitride to a carbide, or from a metal to a metal-ceramic etc. (including any combination), from one to the next phase or Shift, pass over. In principle, the present invention also encompasses all realizable layer systems, independent of the layer thickness profile over the cross section of the layer system. Also, there is no requirement for a possible periodicity of the layers. The layer thicknesses can be chosen arbitrarily and vary from layer to layer. Also, this invention includes all layer systems irrespective of whether they are symmetric with respect to the layer center or not.

Methods which are suitable for the production of the layer system are e.g. CVD and PVD processes, since almost all of these metals, as well as ceramic and amorphous layer materials, can be produced economically and flexibly without interrupting the process. However, other methods are under development and may soon be the subject of one or more other patents.

After fabrication of the layer system in the vertical direction and subsequent shaping of the cutting edge, further ceramic, metallic or diamond-like (e.g., DLC) finishing layers may be applied to the entire surface of the cutting edge, again by suitable CVD or PVD processes.

However, before, ie directly after the production of the layer system and before the first shaping and subsequent application of the outer layers, a heat treatment of the layer system produced, with temperatures between 400 ° C to 1100 ° C and a duration between 1 and 18 hours, into consideration to initiate annealing of potential lattice defects within and at the interfaces of the individual layers, and to selectively control grain growth in the metallic layers.

The present invention is not limited in terms of how the cutting geometries must be formed in detail (angles, widths, etc.) and accordingly leaves room for end user specific requirements for the same. The cutting edges according to the invention are capable of outperforming ceramic cutting edges in terms of cutting ability and of cutting metallic edges, which makes it possible to use these cutting edges in knives, razor blades and other cutting tools such as scalpels. At the same time, their production is not uneconomical, but is cost-effectively in the area of producing high-quality steel or ceramic cutting edges.

The present invention is directed, inter alia, to the following aspects:

Blade with at least one cutting edge, the blade having at least in the region of the cutting edge a multilayer material with at least three layers, metal layers and hard material layers being arranged alternately in the multilayer material. Blade according to aspect 1, wherein in each case at least one metal layer and at least one adjacent metal-ceramic layer have at least one metal element in common. Blade according to aspect 1 or 2, wherein the multi-layer material has at least five, preferably at least seven, more preferably at least nine, particularly preferably at least eleven layers.

(Blade according to aspect 1 or 2, wherein the cutting edge has a cutting edge, which is formed by a first and a second cutting surface, and wherein the first cutting surface with the layers of the multilayer material includes a first angle and the second cutting surface with the layers of the multilayer material second angle, wherein the first and / or second angle is at least 1 °, preferably at least 3 °, more preferably at least 5 ° and more preferably at least 10 °. Blade according to one of the preceding aspects, wherein the thickness of the individual layers is constant and / or between 0.5 nm and 1 mm, preferably between 1 nm and 800 μηι and particularly preferably between 1.5 nm and 600 μιη.

Blade according to one of the preceding aspects, wherein the thickness of the individual layers of the multilayer material increases from the cutting edge toward the edge of the blade. Blade according to one of the preceding aspects, wherein the thickness of at least three central layers in the region of the cutting edge is less than 150 nm, preferably less than 100 nm, and wherein the thickness of at least two outer layers is greater than 150 nm, preferably greater than 200 nm , Blade according to one of the preceding aspects, wherein the cutting edge has at least one additional outer hard material layer. If it is a metal ceramic, it has at least one of the metals contained in the multilayer material, wherein an additional DLC layer is preferably applied to the outer hard material layer. A blade according to any of aspects 1 to 7, wherein the blade has at least one additional outer DLC layer.

Blade according to one of the preceding aspects, wherein at least one metal layer, preferably all metal layers, comprises one or a combination or alloy of the following metals: titanium (Ti), iron (Fe) tantalum (Ta), zirconium (Zr), vanadium (V ), Niobium (Nb), aluminum (Al), hafnium (Hf), chromium (Cr), tungsten (W), boron (B). A blade according to aspect 10, wherein at least one metal-ceramic layer, preferably all metal-ceramic layers comprise one or a combination of the following ceramics based on one or a combination of the metals according to aspect 10: carbide, nitride, carbonitride, boride, oxide, oxynitride, oxicarbide, oxicarbonitride, Boron nitride, boron carbide, diboride, boron carbonitride, oxiboride, oxibomitride, oxibor carbide, oxiborcarbonitride.

Blade according to one of the preceding aspects, wherein different metal layers have different materials.

Blade according to one of the preceding aspects, wherein all metal layers have the same materials. Blade according to one of the preceding aspects, wherein different layers of hard material have different materials.

Blade according to one of the preceding aspects, wherein all hard material layers have the same materials.

Blade according to one of the preceding aspects, wherein at least one metal layer, preferably all metal layers, contain a metal X and at least one of these metal layer adjacent metal ceramic layer one or a combination of the following ceramics carbide, nitride, carbonitride, boride, oxide, oxynitride, oxicarbide, oxicarbonitride , Boron nitride, boron carbide, Borcarbonitrid, Oxiborid, Oxiborcarbid, Oxibomitrid, Oxiborcarbonitrid based on the metal X has. Blade according to one of the preceding aspects, wherein the arrangement of the layers is periodic and / or symmetrical. Blade according to one of the preceding aspects, wherein the arrangement of the layers is aperiodic and / or asymmetric. Blade according to one of the preceding aspects, wherein the blade is a razor blade, a knife blade or a scalpel blade. Multilayer material with at least three layers, wherein in the multilayer material metal layers and hard material layers are arranged alternately. Multilayer material according to aspect 20, wherein in each case at least one metal layer and at least one adjacent metal-ceramic layer have at least one metal element in common. Multilayer material according to aspect 20 or 21, wherein the multilayer material has at least five, preferably at least seven, more preferably at least nine, particularly preferably at least eleven layers.

Multilayer material according to one of the aspects 20 to 22, wherein the thickness of the individual layers is between 0.5 nm and 1 mm, preferably between 1 nm and 800 μm, and particularly preferably between 1.5 nm and 600 μm.

The multilayer material according to any one of aspects 20 to 23, wherein the thickness of the individual layers of the multi-layer material increases from the inside to the outside. Multilayer material according to one of the aspects 20 to 24, wherein the thickness of at least three central layers is less than 150 nm, preferably less than 100 nm and wherein the thickness of at least two outer layers is greater than 150 nm, preferably greater than 200 nm.

Multilayer material according to one of the preceding aspects, wherein at least one metal layer, preferably all metal layers, comprises one or a combination or alloy of the following metals: titanium (Ti), iron (Fe), tantalum (Ta), zirconium (Zr), vanadium ( V), niobium (Nb), aluminum (AI), hafnium (Hf), chromium (Cr), tungsten (W), boron (B).

Multilayer material according to aspect 26, wherein at least one

Metal-ceramic layer, preferably all metal-ceramic layers of the layer system, one or a combination of the following ceramics based on or a combination of the metals of aspect 10: carbide, nitride, carbonitride, boride, oxide, oxynitride, oxicarbide, oxicarbonitride, boron nitride, boron carbide, boron carbonitride, oxiboride, oxibor carbide, oxibomitride, oxiborcarbonitride. Multilayer material according to any of aspects 20 to 27, wherein different metal layers comprise different materials. Multilayer material according to any of aspects 20 to 28, wherein all metal layers have the same materials.

Multilayer material according to aspects 20 to 29, wherein different metal-ceramic layers comprise different materials.

Multilayer material according to any one of aspects 20 to 30, wherein all metal ceramic layers have the same materials. A multilayer material according to any of aspects 20 to 31, wherein at least one metal layer, preferably all metal layers, contain a metal X and wherein at least one metal ceramic layer adjacent to said metal layer comprises one or a combination of the following carbide, nitride, carbonitride, boride, oxide, oxynitride, oxicarbide , Oxicarbonitride, boron nitride, boron carbide, boron carbonitride, oxiboride, oxibomitride, oxiborcarbide, oxiborcarbonitride based on the metal X. Multilayer material according to one of the aspects 20 to 32, wherein the arrangement of the layers is periodic and / or symmetrical. Multilayer material according to one of the aspects 20 to 33, wherein the arrangement of the layers is aperiodic and / or asymmetric.

A cutting edge comprising a multilayer material according to any one of aspects 20 to 34. A cutting edge according to aspect 35, wherein at least a portion of the surface of the cutting edge is formed by the multilayer material. Blade with a cutting edge according to aspect 35 or 36.

Hereinafter, preferred embodiments of the present invention will be described with reference to the figures. Show it:

1 shows a cross section through a multi-layer material according to a preferred embodiment of the present invention.

2 shows a cross section through a multilayer material according to a further preferred embodiment of the present invention;

3 shows a cross section through a multilayer material according to a further preferred embodiment of the present invention;

4 shows a cross section through a cutting edge according to a preferred embodiment of the present invention;

5 shows a cross section through a cutting edge according to a further preferred embodiment of the present invention;

6 shows a cross section through a cutting edge according to a further preferred embodiment of the present invention;

7 shows a cross section through a cutting edge according to a further preferred embodiment of the present invention;

8 shows a cross section through a cutting edge according to a further preferred embodiment of the present invention; 9 shows a cross section through a cutting edge according to a further preferred embodiment of the present invention;

FIG. 1 shows a cross section through a multilayer material according to a preferred embodiment of the present invention. The illustrated multilayer material consists of regularly alternating metal 1 and hard material layers 2. In this case, all metal layers 1 have a constant thickness dM and all hard material layers 2 have a constant thickness dK. This gives a uniform arrangement of parallel layers with a constant thickness. Of course dM and dK can also have different thicknesses and also vary in the vertical course.

FIG. 2 shows a cross section through a multilayer material according to a further preferred embodiment of the present invention. The illustrated multilayer material has 23 layers (including the two outermost edge or carrier layers), metal layers 1 and hard material layers 2 being arranged alternately in the multilayer material. Apart from the two outermost metal layers 1a, all metal layers 1 have a constant thickness dM and all hard material layers have a constant thickness dK, as shown in FIG. This gives a symmetrical arrangement of parallel layers of constant thickness. In the illustrated embodiment, furthermore, the thickness dM of the metal layers is the same size as the thickness dK of the hard material layers. Only the thickness of the two outermost layers la is significantly greater than the thickness of the remaining layers.

Of course, the features of this preferred embodiment are by no means to be considered as limiting or necessary for the invention. Thus, more or fewer layers than the 23 illustrated layers may be provided. Also, the thickness dM of the metal layers need not be identical to the thickness dK of the hard material layers, but may be larger or smaller than these. It is also not necessary that all metal layers or all hard material layers have the same thickness. Rather, for example, increase the thickness of the metal layers from the inside out (or decrease). The thickness of the hard material layers can also increase (or decrease) from the inside to the outside. Although it is beneficial if the two outermost Metal (or hard) layers la, as shown in Figure 2, have a greater thickness, so this is not necessary. The thickness of the individual layers also does not have to remain constant within a layer, but may, for example, increase from one side to the other side or vary in any other way, but also as a result of production.

FIG. 3 shows a cross section through a further preferred embodiment of the multilayer material according to the invention. This multilayer material has a total of 15 layers (including the carrier or edge layers), wherein in turn metal layers 1 with hard material layers 2 are arranged alternately. In contrast to the embodiment of Figure 1, however, different layer thicknesses are provided in this embodiment.

Thus, the innermost 7 layers 1 a and 2 a have a thickness d3, the respective adjacent layers lb and 2b have a layer thickness d2 and the metal ceramic layers 2c adjoining it to the outside have a layer thickness d1. In this case, the layer thicknesses increase from the inside to the outside, so that the following applies for the illustrated embodiment: d1> d2> d3. Furthermore, the layer thickness for the innermost metal and hard material layers la and 2a is the same size. The same applies to the subsequent middle metal and hard material layers 1b and 2b. However, as already explained with regard to FIG. 2, this is not necessary. Rather, the layer thickness of the individual metal layers may differ from that of the individual hard material layers. The layer thickness can also increase more uniformly from layer to layer. It is also possible that the layer thickness decreases from the inside to the outside. Furthermore, the layer thickness can also vary within a single layer and, for example, increase from one side to the other side or vary in any other way, but also as a result of production.

FIG. 4 shows a cross section through a cutting edge according to a preferred embodiment of the present invention. The cutting edge 10 has a first cutting surface 11 and a second cutting surface 12, which meet at a cutting edge 13 and enclose a non-designated wedge angle. Furthermore, the first cutting surface 11 encloses the angle α with the layers of the multilayer material. This is preferably at least 1 °, more preferably at least 3 °, even more preferably at least 5 °, and most preferably at least 10 °. There In the illustrated embodiment, it is a symmetrical cutting edge (and accordingly first and second cutting surfaces can not really be distinguished from each other), here also the second cutting surface 12 includes the same angle α with the layers of the multilayer material.

The cutting edge 10 in Figure 4 consists of a multi-layer material, as shown in Figure 1. Accordingly, the following applies to the sequence and layer thickness of the metal layers 1 and hard material layers 2 the above to Figure 1. Over the entire cross section of the cutting edge, the alternating layers have the same thickness.

Of course, the cutting geometry illustrated therein is to be understood merely as an example. In particular, the cutting edge geometry does not have to be symmetrical and the wedge angle may deviate from the illustrated angle

FIG. 5 shows a cross section through a cutting edge according to a further preferred embodiment of the present invention. The cutting edge 10 has a first cutting surface 11 and a second cutting surface 12, which meet at a cutting edge 13 and enclose a non-designated wedge angle. Furthermore, the first cutting surface 11 encloses the angle α with the layers of the multilayer material. This is preferably at least 1 °, more preferably at least 3 °, even more preferably at least 5 °, and most preferably at least 10 °. Since in the illustrated embodiment is a symmetrical cutting edge (and accordingly first and second cutting surface are not really different from each other), here includes the second cutting surface 12 has the same angle α with the layers of the multi-layer material.

The cutting edge 10 in Figure 5 consists of a multi-layer material, as shown in Figure 2. Accordingly, the following applies to the sequence and layer thickness of the metal layers 1 and hard material layers 2 the above to Figure 2. As can be clearly seen in FIG. 5, the outermost metal layers 1a having a significantly greater layer thickness are preferably arranged only in that region of the cutting edge 10 which is so far away from the two cutting surfaces that these layers 1a are not significantly stressed mechanically. In the area of the two cutting surfaces and in particular in the vicinity of the cutting edge 13, however, there is preferably a narrow layer of alternating metal and hard material layers. At least three layers, more preferably at least five layers and particularly preferably at least seven layers are preferably provided in the region of the cutting surfaces, as shown in FIG.

Of course, the cutting geometry illustrated therein is to be understood merely as an example. In particular, the cutting edge geometry does not have to be symmetrical and the wedge angle may deviate from the illustrated angle.

FIG. 6 shows a further preferred embodiment of a cutting edge 10 according to the invention. This cutting edge is manufactured from the multilayer material according to FIG. This embodiment makes it particularly clear why a multilayer material with increasing layer thickness from the inside to the outside can be used particularly advantageously for a cutting edge: In the region of the cutting edge 13, seven alternating metal layers 1a and hard material layers 2a of particularly small layer thickness d3 are arranged here. As a result, the cutting ability and edge retention of the cutting edge 10 in the region of the cutting edge 13 is particularly large. This narrow stratification, which at the same time makes the production more expensive, is not absolutely necessary in the outer layers 1b and 2b and in particular 1c and 2c, since they are sufficiently far away from the cutting edge 13 and thus are not exposed to the same mechanical stresses.

In the illustrated embodiment, the cutting edge 10 has an additional, outer hard material layer 3, which preferably has at least one of the metals contained in the multilayer material, if the hard material layer is a metal ceramic. Furthermore, an additional hard material layer 4 is applied to the outer hard material layer 3, for example a DLC layer. Of course, one or both of these layers can be dispensed with. Just as well, the outer hard material layer 3 and / or the hard material layer 4 may also be provided in the embodiment according to FIG. It can also be provided a plurality of different outer hard material layers. FIG. 7 shows a further preferred embodiment of a cutting edge 10 according to the invention. The cutting edge 10 has a first cutting face 11 and a second cutting face (or rake face) 12, which meet at a cutting edge 13 and enclose a wedge angle. Further, the first cutting surface 11 includes the angle cd with the layers of the multi-layer material. This is preferably at least 1 °, more preferably at least 3 °, even more preferably at least 5 °, and most preferably at least 10 °. The second cutting surface (or rake surface) 12 encloses the angle ot2 with the layers of the multilayer material. In contrast to the embodiment of FIGS. 5 and 6, this is an asymmetrical cutting edge with l> a2, where in the illustrated example, al> 0 ° and a2 = 0 °, so that the wedge angle al corresponds. In other words, in this embodiment, the second cutting surface (or rake surface) 12 is arranged parallel to the layers of the multilayer material.

Alternatively, the first cutting surface 11 may also be arranged parallel to the layers of the multilayer material, as shown in FIG. Here, al <a2, al = 0 ° and a2> 0 °, so that the wedge angle is a2.

Of course, none of the cutting surfaces need be arranged parallel to the layers. Rather, the first and second cutting surfaces may each include different angles with the layers of the multilayer material, each greater than 0 °. Such an embodiment is depicted in FIG. 9 in which al <a2, al> 0 ° and a2> 0 °, so that the wedge angle corresponds to the sum of a1 and a2.

Of course, the features with regard to the alignment of the layers of FIGS. 7 to 9 with the features with regard to the layer thicknesses of FIG. 6 can be combined with one another.

Claims

claims

1. Blade with at least one cutting edge, the blade having at least in the region of the cutting edge a multilayer material with at least five layers, wherein in the multilayer material metal layers and metal ceramic layers are arranged alternately and wherein in each case at least one metal layer and at least one adjacent metal ceramic layer have at least one metal element in common ,

2. Blade according to claim 1, wherein the cutting edge has at least one additional, outer hard material layer, which has at least one of the metals contained in the multilayer material and wherein preferably on the outer hard material layer, an additional DLC layer is applied.

The blade of claim 1, wherein the blade has at least one additional outer DLC layer.

4. Blade according to one of the preceding claims, wherein at least one metal layer, preferably all metal layers containing a metal X and wherein at least one metal layer adjacent, a metal-ceramic layer, one or a combination of the following ceramics: carbide, nitride, carbonitride, boride, oxide, Oxynitride, oxicarbide, oxicarbonitride, boron nitride, boron carbide, diboride, Borcarbonitrid, Oxiborid, Oxibornitrid, Oxiborcarbid, Oxiborcarbonitrid based on the metal X has.

5. Blade with at least one cutting edge, the blade having a multilayer material with at least five layers at least in the area of the cutting edge, wherein carbide-forming metal layers and DLC layers are arranged alternately in the multilayer material

6. Blade according to one of the preceding claims, wherein the multi-layer material has at least seven, preferably at least nine, more preferably at least eleven layers.

A blade according to any one of the preceding claims, wherein the blade has a cutting edge formed by first and second cutting surfaces, and wherein the first cutting surface includes a first angle with the layers of the multilayer material and the second cutting surface includes the layers of the multilayer material includes a second angle, wherein the first and / or second angle is at least 1 °, preferably at least 3 °, more preferably at least 5 ° and most preferably at least 10 °.

8. Blade according to one of the preceding claims, wherein the preferably constant thickness of the individual layers between 0.5 nm and 1 mm, preferably between 1 nm and 800 μηι and particularly preferably between 1.5 nm and 600 μπι.

A blade according to any one of the preceding claims, wherein the thickness of the individual layers of the multilayer material increases from the cutting edge towards the edge of the blade.

Blade according to one of the preceding claims, wherein at least some of the layers have a different thickness and are arranged such that the thickness of these layers increases from the cutting edge towards the edge of the blade.

Blade according to one of the preceding claims, wherein one or more layers in the region of the cutting edge have a thickness which is smaller than the thickness of one or more layers in the region of the edge of the blade.

12. Blade according to one of the preceding claims, wherein the thickness of at least three central layers in the region of the cutting edge is less than 150 nm, preferably less than 100 nm, and wherein the thickness of at least two outer layers is greater than 150 nm, preferably greater than 200 nm is.

13. Blade according to one of the preceding claims, wherein at least a part of the surface of the cutting edge is formed by the multi-layer material.