Patent Application
20240017379
The invention relates to a method for the production of a grinding tool and a grinding tool.
In lightweight construction, hybrid components are applied in which carbon fiber reinforced plastics (CFRP) are used in combination with light metals. Carbon fiber reinforced plastics are electrically conductive and have a high electrochemical potential, so that corrosion can be caused on the less noble light metal.
It is an object of the invention to provide a simple and economical method for the production of a grinding tool that can be used without restriction in lightweight construction. The grinding tool produced by means of the method is to be applicable in particular in the aerospace industry.
This object is achieved by a method for the production of a grinding tool comprising the steps of providing an auxiliary body, applying a metal layer to the auxiliary body, separating the metal layer from the auxiliary body, fixing the metal layer to a tool base body, and applying a grinding layer to the metal layer. At least one metal is applied to the auxiliary body so that a metal layer is formed. The metal layer is then separated from the auxiliary body. The metal layer is preferably elastic and/or ductile. In particular, the metal layer is formed in a film-like manner Subsequently, the metal layer is fixed to a tool base body and a grinding layer is applied to the metal layer. The auxiliary body is preferably plate-like, in particular disc-like. For example, the grinding layer is galvanically applied to the metal layer.
The metal layer forms a substrate and is selected according to the machining requirements in lightweight construction. In particular, the metal layer is formed in such a manner that contamination from the at least one metal that arises during machining does not promote corrosion of hybrid components in lightweight construction. Such contamination thus does not lead to increased corrosion of a light metal that is combined with a fiber composite material, in particular a CFRP material, in a hybrid component.
Preferably, at least one metal of the metal layer has an electrical conductivity σ, wherein in particular: 1·106 S/m≤σ≤50·106 S/m, in particular 5·106 S/m≤σ≤35·106 S/m, and in particular 10·106 S/m≤σ≤20·106 S/m. Preferably, the at least one metal of the metal layer with the highest weight fraction has the electrical conductivity σ. In particular, all metals of the metal layer have the electrical conductivity σ.
Preferably, at least one metal of the metal layer has a standard potential E0, wherein in particular: 0.35 V≤E0≤1.8 V, in particular 0.55 V≤E0≤1.6 V, in particular 0.75 V≤E0≤1.4 V, and in particular 0.95 V≤E0≤1.2 V. Preferably, the at least one metal of the metal layer with the highest weight fraction has the standard potential E0. In particular, all metals of the metal layer have the standard potential E0.
The standard potential E0 is also called normal potential. The normal potential corresponds in particular to the potential of a standard metal electrode against the standard hydrogen electrode at 25° C. and 101.3 kPa. The normal potential is defined, for example, in the Römpp Chemielexikon (=chemistry encyclopedia).
Preferably, at least one metal of the metal layer is nobler than copper. At least one metal of the metal layer has a standard potential E0, which is in particular higher than the standard potential E0 of copper. Preferably, all metals of the metal layer have a standard potential E0, which is higher than the standard potential E0 of copper.
If the at least one metal has several standard potentials E0 in each case, the embodiments and ranges apply in particular to the highest standard potential E0.
The at least one metal is selected in particular from the group consisting of nickel, stainless steel and gold.
The metal layer preferably has at least 90% by weight, in particular at least 95% by weight, in particular at least 99% by weight, and in particular at least 99.9% by weight of a single metal. Preferably, the metal layer consists of exactly one metal.
The tool base body has a connection means, in particular a hub or a shaft, for clamping and rotationally driving the grinding tool. The tool base body is, for example, plate-shaped. The tool base body preferably does not comprise any metal. The tool base body is preferably made exclusively of at least one non-metallic material. The tool base body comprises at least one material from the group consisting of vulcanized fiber, polyester, glass fibers, carbon fibers, cotton and plastic. The tool base body is in particular of single-layer or multi-layer construction. The tool base body is in particular flexible and/or rigid at least in some regions.
The grinding layer comprises a binder and abrasive grains. In particular, the binder comprises at least one material from the group consisting of thermosets, elastomers, thermoplastics and synthetic resins. Preferably, the binder is a thermoset, in particular phenolic resin or epoxy resin. The phenolic resin is, for example, a resol or a novolak. The binder can be applied to the tool base body in a random manner.
The abrasive grains have a geometrically definite and/or a geometrically indefinite shape. The abrasive grains comprise at least one material selected from the group consisting of ceramic, corundum, in particular zirconium corundum and aluminum oxide, diamond, cubic crystalline boron nitride, silicon carbide and tungsten carbide. The abrasive grains can be applied in a single layer or in multiple layers.
Preferably, the metal layer is first fixed to the tool base body and then the grinding layer is applied to the metal layer. A first side of the metal layer is connected to the tool base body, whereas an opposite second side of the metal layer is connected to the grinding layer.
A method in which the auxiliary body comprises titanium ensures a simple and economical production of the grinding tool. The auxiliary body forms a passive layer on the surface which prevents the metal layer from adhering strongly to the auxiliary body. The metal layer can thus be easily separated from the auxiliary body. The auxiliary body is suitable for galvanic coating or galvanic application of the metal layer. The auxiliary body is easy to clean and can be used repeatedly. Preferably, the auxiliary body comprises at least 90% by weight of titanium, in particular at least 95% by weight of titanium, in particular at least 99% by weight of titanium and in particular at least 99.9% by weight of titanium. Preferably, the auxiliary body comprises 100% by weight of titanium.
A method in which the metal layer comprises nickel ensures a simple and economical production of the grinding tool and an unrestricted applicability in lightweight construction. Preferably, the metal layer comprises at least 90% by weight of nickel, in particular at least 95% by weight of nickel, in particular at least 99% by weight of nickel, and in particular at least 99.9% by weight of nickel. Preferably, the metal layer comprises 100% by weight of nickel. The metal layer or nickel layer is easily separable from the auxiliary body. The metal layer or nickel layer is preferably elastic and/or ductile. Due to the low electrical conductivity σ and/or the high standard potential E0 nickel does not favor the corrosion of hybrid components in lightweight construction. Nickel contamination that remains on the hybrid component due to machining of a hybrid component by means of the grinding tool is therefore unproblematic.
A method in which the metal layer is applied with a layer thickness D, wherein: 0.005 mm≤D≤1.5 mm, in particular 0.05 mm≤D≤1.2 mm, and in particular 0.1 mm≤D≤1 mm, ensures a simple and economical production of the grinding tool. On the one hand, the layer thickness D ensures that the metal layer is sufficiently stable so that it can be separated from the auxiliary body and connected to the tool base body. On the other hand, the layer thickness D ensures that the metal layer is sufficiently elastic or flexible and/or ductile so that it can be adapted to a shape of the tool base body. In particular, the metal layer is designed in the form of a film.
A method in which the metal layer is applied galvanically to the auxiliary body ensures a simple and economical production of the grinding tool. By means of the galvanic coating, the metal layer is evenly applied to the auxiliary body. The coating can be controlled in a simple manner.
A method in which the auxiliary body and at least one coating metal body are arranged in an electrolyte ensures a simple and economical production of the grinding tool. For the galvanic coating, the auxiliary body and at least one coating metal body are arranged in an electrolyte. The auxiliary body and the at least one coating metal body are connected to a voltage source. The auxiliary body forms a cathode, whereas the at least one coating metal body forms an anode. The auxiliary body is preferably plate-like, in particular disc-like. Preferably, at least one first coating metal body is arranged on a first side of the auxiliary body, whereas at least one second coating metal body is arranged on a second side of the auxiliary body. This allows a metal layer to be applied to the two sides of the auxiliary body. The electrolyte is preferably arranged in a container.
A method in which an electrolyte and solid particles form a suspension ensures a simple and economical production of the grinding tool. Due to the fact that the electrolyte and solid particles form a suspension, the solid particles can be introduced into the metal layer and/or applied to the metal layer during the galvanic coating of the auxiliary body. This increases the surface roughness of the metal layer so that the bond with the tool base body and/or the grinding layer is improved in a simple manner Preferably, the electrolyte is set in motion so that the solid particles are not deposited and are kept in suspension. Preferably, at least 70% by weight, in particular at least 80% by weight, and in particular at least 90% by weight of the solid particles have a grain diameter d, wherein: 0.015 mm≤d≤0.15 mm, in particular 0.03 mm≤d≤0.12 mm, and in particular 0.05 mm≤d≤0.1 mm. The solid particles are in particular selected from the group consisting of ceramic particles, glass particles and/or quartz particles or quartz grains.
A method in which solid particles are introduced into the metal layer and/or applied to the metal layer ensures a simple and economical production of the grinding tool. The solid particles increase the surface roughness of the metal layer so that the bond with the tool base body and/or the grinding layer is improved. Preferably, at least 70% by weight, in particular at least 80% by weight, and in particular at least 90% by weight of the solid particles have a grain diameter d, wherein: 0.015 mm≤d≤0.15 mm, in particular 0.03 mm≤d≤0.12 mm, and in particular 0.05 mm≤d≤0.1 mm. The solid particles are in particular selected from the group consisting of ceramic particles, glass particles and/or quartz particles or quartz grains.
A method in which the metal layer is glued to the tool base body ensures a simple and economical production of the grinding tool. Preferably, the metal layer has an increased surface roughness due to introduced and/or applied solid particles, so that the adhesive bond between the tool base body and the metal layer is improved. In particular, the solid particles improve the cross-linking of the adhesive, which makes the bond stronger. Preferably, an adhesive layer is applied to the tool base body and/or the metal layer. In particular, the adhesive bonding is carried out under the action of a pressure increased with respect to the ambient pressure and/or a temperature increased with respect to the ambient temperature. Preferably, the adhesive bonding is carried out by means of a press, which in particular can be heated.
A method in which the auxiliary body and/or the metal layer are copper-free ensures unrestricted applicability of the grinding tool in lightweight construction. Due to the fact that the metal layer and in particular also the auxiliary body do not comprise copper, i.e. are copper-free, copper contamination of a hybrid component machined by means of the grinding tool is prevented. The auxiliary body and/or the metal layer are 100% copper-free. Thus, there is no risk of corrosion due to the machining of a hybrid component by means of the grinding tool.
It is further an object of the invention to provide a grinding tool that can be produced simply and economically and can be used without restriction in lightweight construction. In particular, the grinding tool is intended for unrestricted use in the aerospace industry.
This object is achieved by a grinding tool comprising a tool base body, a metal layer fixed to the tool base body, and a grinding layer fixed to the metal layer. The advantages of the grinding tool according to the invention correspond to the advantages of the method according to the invention. The grinding tool according to the invention can in particular be further embodied with at least one feature described in connection with the method according to the invention for the production of the grinding tool.
A grinding tool configured such that the metal layer comprises nickel ensures unrestricted applicability in lightweight construction. Preferably, the metal layer comprises at least 90% by weight of nickel, in particular at least 95% by weight of nickel, in particular at least 99% by weight of nickel, and in particular at least 99.9% by weight of nickel. Preferably, the metal layer comprises 100% by weight of nickel. The metal layer or nickel layer is easily separable from the auxiliary body. Preferably, the metal layer or nickel layer is elastic and/or ductile. The metal layer or nickel layer is preferably film-like. Due to the low electrical conductivity σ and/or the high standard potential E0, nickel does not favor corrosion of hybrid components in lightweight construction. Nickel contamination that remains on the hybrid component due to machining of a hybrid component by means of the grinding tool is therefore unproblematic.
A grinding tool configured such that the metal layer has a layer thickness D, wherein: 0.005 mm≤D≤1.5 mm, in particular 0.05 mm≤D≤1.2 mm, and in particular 0.1 mm≤D≤1 mm, ensures a simple and economical production of the grinding tool. On the one hand, the layer thickness D ensures that the metal layer is sufficiently stable so that it can be separated from the auxiliary body and connected to the tool base body. On the other hand, the layer thickness D ensures that the metal layer is sufficiently elastic or flexible and/or ductile so that it can be adapted to a shape of the tool base body. In particular, the metal layer is designed in the form of a film.
A grinding tool configured such that solid particles are arranged in the metal layer and/or on the metal layer ensures a simple and economical production of the grinding tool. The solid particles increase the surface roughness of the metal layer so that the bond with the tool base body and/or the grinding layer is improved. Preferably, at least 70% by weight, in particular at least 80% by weight, and in particular at least 90% by weight of the solid particles have a grain diameter d, wherein: 0.015 mm≤d≤0.15 mm, in particular 0.03 mm≤d≤0.12 mm, and in particular 0.05 mm≤d≤0.1 mm. The solid particles are in particular selected from the group consisting of ceramic particles, glass particles and/or quartz particles or quartz grains.
A grinding tool configured such that the metal layer is glued to the tool base body ensures a simple and economical production of the grinding tool. Preferably, the metal layer has an increased surface roughness due to introduced and/or applied solid particles, so that the adhesive bond between the tool base body and the metal layer is improved. In particular, the solid particles improve the cross-linking of the adhesive, which makes the bond stronger.
A grinding tool configured such that the metal layer is copper-free ensures unrestricted applicability of the grinding tool in lightweight construction. Due to the fact that the metal layer does not comprise copper, i.e. is copper-free, copper contamination of a hybrid component machined by means of the grinding tool is prevented. The metal layer is 100% copper-free. There is therefore no risk of corrosion due to the machining of a hybrid component by means of the grinding tool.
This object is further achieved by a grinding tool produced according to a method described above.
Another independent aspect of the invention relates to the use of a grinding tool according to the above description for machining components, in particular hybrid components, in lightweight construction. Such hybrid components comprise a fiber composite material, for example comprising carbon fibers and/or glass fibers, and a light metal, for example aluminum, magnesium and/or titanium.
Further features, advantages and details of the invention will be apparent from the following description of an embodiment example.
The grinding tool 1 serves to machine components, in particular hybrid components, in lightweight construction. Such hybrid components comprise a fiber composite material and a light metal. The fiber composite material has, for example, carbon fibers.
To obtain the grinding tool 1, a metal layer 3 or metal layers 3 are produced in a step S1. An apparatus for producing film-like metal layers 3 is provided. The apparatus is illustrated in
A first coating metal body 8 and a second coating metal body 9 are further arranged in the electrolyte 6. The first coating metal body 8 faces the first deposition surface A1, whereas the second coating metal body 9 faces the second deposition surface A2. The auxiliary body 7 is electrically connected to a negative pole of a voltage source 10, whereas the coating metal bodies 8, 9 are electrically connected to a positive pole of the voltage source 10. The voltage source 10 generates an adjustable voltage U.
The auxiliary body 7 comprises at least 90% by weight of titanium, in particular at least 95% by weight of titanium, in particular at least 99% by weight of titanium, and in particular at least 99.9% by weight of titanium. Preferably, the auxiliary body 7 comprises 100% by weight of titanium.
The coating metal bodies 8, 9 preferably consist of a metal selected from the group consisting of nickel, stainless steel and gold. The coating metal bodies 8, 9 comprise, for example, at least 90% by weight of nickel, in particular at least 95% by weight of nickel, in particular at least 99% by weight of nickel, and in particular at least 99.9% by weight of nickel. Preferably, the coating metal bodies 8, 9 comprises 100% by weight of nickel.
Preferably, at least one metal of the metal layer 3 has an electrical conductivity σ, wherein in particular: 1·106 S/m≤σ≤50·106 S/m, in particular 5·106 S/m≤σ≤35·106 S/m, and in particular 10·106 S/m≤σ≤20·106 S/m. Preferably, the at least one metal of the metal layer 3 with the highest weight fraction has the electrical conductivity σ. In particular, all metals of the metal layer 3 have the electrical conductivity σ.
Preferably, at least one metal of the metal layer 3 has a standard potential E0, wherein in particular: 0.35 V≤E0≤1.8 V, in particular 0.55 V≤E0≤1.6 V, in particular 0.75 V≤E0≤1.4 V, and in particular 0.95 V≤E0≤1.2 V. Preferably, the at least one metal of the metal layer 3 with the highest weight fraction has the standard potential E0. In particular, all metals of the metal layer 3 have the standard potential E0.
The standard potential E0 is also called normal potential. In particular, the normal potential corresponds to the potential of a standard metal electrode against the standard hydrogen electrode at 25° C. and 101.3 kPa. The normal potential is defined, for example, in the Römpp Chemielexikon.
Preferably, at least one metal of the metal layer 3 is nobler than copper. At least one metal of the metal layer 3 has a standard potential E0, which is in particular higher than the standard potential E0 of copper. Preferably, all metals of the metal layer 3 have a standard potential E°, which is higher than the standard potential E0 of copper.
If the at least one metal has several standard potentials E0 in each case, the embodiments and ranges apply in particular to the highest standard potential E0.
The at least one metal is selected in particular from the group consisting of nickel, stainless steel and gold.
Solid particles 11 are arranged in the electrolyte 6. The electrolyte 6 and the solid particles 11 form a suspension. For this purpose, the apparatus has means, not shown in more detail, for generating a motion or flow in the electrolyte 6. The solid particles 11 have a grain size or a grain diameter d. The following applies in particular to the grain diameter d: 0.015 mm≤d≤mm, in particular 0.03 mm≤d≤0.12 mm, and in particular 0.05 mm≤d≤0.1 mm. The solid particles are in particular selected from the group consisting of ceramic particles, glass particles and/or quartz particles or quartz grains.
In a step S2 the metal layers 3 are galvanically deposited on the auxiliary body 7. The voltage U is switched on for this purpose. The auxiliary body 7 forms a cathode, whereas the coating metal bodies 8, 9 form anodes. Nickel atoms detach from the coating metal bodies 8, 9 and move in the electrolyte 6 to the deposition surfaces A1 and A2. The nickel atoms are deposited on the deposition surfaces A1 and A2 so that the metal layers 3 are galvanically deposited or applied to the auxiliary body 7. The metal layers 3 deposited on the deposition surfaces A1 and A2 are illustrated in
Due to the fact that the electrolyte 6 and the solid particles 11 form a suspension, solid particles 11 are introduced into the metal layers 3 and/or applied to the metal layers 3 during the galvanic deposition of the metal layers 3. The solid particles 11 increase a surface roughness of the metal layers 3.
If the metal layers 3 have a desired layer thickness D, the deposition procedure is terminated by switching off the voltage U. The following preferably applies to the layer thickness D: 0.005 mm≤D≤1.5 mm, in particular mm≤D≤1.2 mm, and in particular 0.1 mm≤D≤1 mm. The auxiliary body 7, the coating metal bodies 8, 9 and the metal layers 3 are 100% copper-free.
In a step S3 the metal layers 3 are separated from the auxiliary body 7. This is done, for example, by pulling the metal layers 3 off the auxiliary body 7. The film-like metal layers 3 are elastic or flexible and ductile. After the metal layers 3 have been separated, the auxiliary body 7 can be galvanically coated again with metal layers 3. This is done in the manner described above. If necessary, the auxiliary body 7 must be cleaned. If necessary, the coating metal bodies 8, 9 must be renewed and/or solid particles 11 must be supplemented in the electrolyte 6.
In a step S4 one of the separated metal layers 3 is attached to a tool base body 2. For this purpose, an adhesive layer 12 is applied to the tool base body 2. The metal layer 3 is then arranged on the adhesive layer 12. Due to the fact that the metal layer 3 is elastic or flexible and ductile, the metal layer 3 adapts to the shape of the tool base body 2. The metal layer 3 is pressed with a pressure p against the tool base body 2. The adhesive layer 12 cures under the application of the pressure p at a desired temperature T. After the adhesive layer 12 has cured, the metal layer 3 is firmly bonded to the tool base body 2. This is illustrated in
As the solid particles 11 increase the surface roughness of the metal layer 3, the cross-linking of the adhesive or adhesive layer 12 is increased, which increases the strength of the bond between the tool base body 2 and the metal layer 3.
The tool base body 2 has a connection means 13 for clamping and rotationally driving the grinding tool 1 by means of a tool drive which is not shown in more detail. The connection means 13 is designed, for example, as a hub or opening. The tool drive can preferably be guided manually. The tool base body 2 is designed, for example, in the shape of a plate. The tool base body 2 comprises at least one material from the group consisting of vulcanized fiber, polyester, glass fibers, carbon fibers, cotton and plastic. The tool base body 2 is in particular of single-layer or multi-layer construction. The tool base body 2 is in particular flexible and/or rigid at least in some regions.
In a step S5, a grinding layer 4 is applied to the metal layer 3. The grinding layer 4 comprises a binder 14 and abrasive grains 15, 16. The binder 14 with the abrasive grains 15 embedded therein is applied to the metal layer 3. Additional abrasive grains 16 are applied to the side of the binder 14 facing away from the metal layer 3. By curing the binder 14, the grinding layer 4 is bonded to the metal layer 3 and the tool base body 2. Increased surface roughness of the metal layer 3 due to the embedded solid particles 11 improves the bond between the metal layer 3 and the grinding layer 4.
Due to the 100% copper-free nature of the machining tool 1, it is suitable for machining components, in particular hybrid components, in the aerospace industry. The absence of copper prevents metal contamination or nickel contamination due to machining of the component with the grinding tool 1 according to the invention from promoting corrosion.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2020/083079 | 11/23/2020 | WO |
