SE513219C2 - Wear surface and process for making the same - Google Patents

Abstract

A method for the manufacturing of a hard wear resistant surface of PVD-material on a soft foundation or on large objects, wherein a piece of metal sheet of hard material is coated by means of a PVD-method with a layer of PVD, which is harder than the metal sheet, and wherein the metal sheet or parts thereof is then glued, with the side that is facing away from the PVD-coating, at the position on the softer foundation or larger object, in which the wear resistant surface is desired. Since the meal sheet, that preferably may have the shape of a tape, is hard the layer of PVD is supported, so that the deformations at the expected point loads become so small that the layer of PVD does not fracture.

Description

15 20 25 30 513 219 2 which would be deformed by the coating temperature.

Correct surface condition: The thin, heavily loaded PVD layer also places high demands on the nature of the coating surface, mainly in terms of surface finish. Usually a slightly sanded or polished surface that is not affected by the machining is required, which can be difficult to achieve on complicated geometries. At the same time, it is required that the entire object is free of contaminants that can evaporate in the coating process.

The invention is intended to provide a method of using PVD layers (eg carbides, nitrides, borides, oxides, etc.) to protect against wear and friction even large objects, internal and obscured surfaces, objects made of softer construction materials or of materials such as does not withstand 200 ° C, and on surfaces that do not have the right surface condition.

This is done by instead of applying the layer directly to the objects, applying it to a thin metal strip or a thin sheet, the hardness of which gives the layer sufficient bearing capacity, and which is then applied to the surfaces which are subjected to abrasion or friction.

By applying the PVD layer to a belt which is flushed between two rollers in front of the coating source, large areas can be coated extremely cost-effectively. In the continuous process, full control is offered over the quality-influencing factors such as temperature and angle and distance to the coating source. This creates the constant conditions that are a condition for the most advanced PVD layers.

The thin strip or plate is advantageously of hardened steel, e.g. martensitic stainless steel, which is available in thin strips. The expensive alloying elements needed to support the layer are then concentrated on the strip, while the object can otherwise be made of simpler materials.

The surface of the strip is processed and heat treated efficiently to the surface condition and hardness required. When coating, the strip is turned so that the degrees from the wear of the strip are turned backwards, alternatively the strip is embossed during the wear so that the degree is evened out.

The thickness of the strip must be sufficient to support the layer but still so thin that the strip can be formed to the surfaces to which it is to be attached.

When mounting on the wear surfaces, the strip is cut to suitable lengths and preferably applied with some adhesive. The adhesive can be applied during assembly or during the production of the belt. In the latter case, the tape is delivered as an adhesive tape. By choosing a PVD layer that has a lower surface energy than the underside of the belt, the adhesive will remain on the underside when the belt is unrolled.

The cutting is advantageously done in an I-shaped punching tool so that the degree of the cut pieces is turned downwards, which prevents wear from being initiated on the edge. 10 15 20 25 30 513 219 3 By spirally winding the strip and cutting it diagonally, it can also be used to protect radial surfaces outside and inside.

Because the PVD layer bearing band (or its surface layer) is hard, this will not be deformed at point load (within moderate limits) more than the elasticity or plasticity of the PVD layer allows and thus the PVD layer, in In addition, crystalline structure has shortcomings: and is destroyed. Therefore, even with point loads, a very good wear resistance, low friction fi and high strength and no scratches occur, resulting in a long service life. The invention makes it possible to create in particular flat wear surfaces of almost any size as it is possible to use your separately manufactured elements next to each other. Since sheets as well as strips and PVD layers are flexible and malleable within certain limits, it is also conceivable to achieve curved both convex and concave surfaces, where the shape of the surface is determined first at the fixing or in a separate forming process immediately before. i Formability means that even double-curved surfaces (eg spherical) can be achieved if the deformation is not too great. Furthermore, by embossing the strip or sheet, a division of the surface into many small units can be achieved so that the formability increases by allowing the deformations to be channeled to the thinner material in the embossments without deteriorating the adhesion of the PVD layer in the intermediate surfaces.

The choice of coating material, strip or sheet material as well as the adhesive or adhesive layer used is adapted to the end of use needle. In this way, the invention contributes to a significantly increased freedom of choice in material selection during construction.

Due to the fact that PVD layers, in addition to the good abrasion resistance, also have very low friction, it is conceivable to use the invention to provide PVD-coated bearing surfaces. In some types of bearings, it is traditionally desired to ensure a good friend transfer between the bearing surface and the associated part for dissipation of the heat generated in the bearing due to friction. Arranging a heat-insulating adhesive layer here between the bearing surface and the object in question seems at first sight completely unreasonable, but since the possible bearing surfaces with the invention can be given a very low friction, the need for heat transport decreases and any frictional heat can be further dissipated. the second part of the warehouse.

Further advantages and features of the invention will become more apparent from the following description of a preferred embodiment, shown in the accompanying drawing. The drawing shows on a considerably enlarged scale a section through fat strip in accordance with the invention. The strip 1 shown in the drawing can for instance be made of stainless steel. On the upwardly facing side of the strip, a PVD layer 2 of, for example, a metal oxide, metal nitride, metal boride, carbon nitride, carbon or any other hard compound of metals, semiconductors with oxygen, nitrogen, fluorine, boron, etc., alternatively mixtures has been applied in a vacuum chamber. of such compounds. On the underside of the belt this is fixed to a base 4 by means of a suitable line 3.

The thickness of the metal strip (or sheet metal pieces) is dimensioned to provide a sufficiently hard support for the PVD layer at the expected point loads so that at an expected point load this is not extended more than its elasticity or plasticity allows so that cracks and peeling are avoided.

The metal strip does not have to be homogeneous but can, for example, be hardened in its surface facing the PVD layer, alternatively the metal strip itself may comprise fl your layers, suitably with the hardest facing the PVD layer. The abrasion-resistant PVD layer can also be made up of fl your layers to achieve the desired properties. The adhesive can advantageously be applied already during the production of the coated strip. In this way, an even and uniform blow-free liner coating can be achieved at the same time as the application at the intended place is considerably simplified. By storing the prefabricated wear tape in the form of a rule, the advantage is also obtained that the adhesive layer holds the roll together and is protected by the abutment against the PVD layer of the previous round. The roll also becomes tender and easy to handle. All that is required is a pair of scissors or equivalent. If desired, the strip can of course be punched into desired pieces and shapes, which can optionally be stored in stacks of adhering pieces.

The manufactured steel strip can then be sold as a wear surface or bearing surface on a roll and during use can simply be cut into reasonably large pieces which are then stapled in the right place. In order to ensure that no burrs or the like can lead to the tear-off or damage of the surface layer when cutting the strip, the learning obligation takes place in such a way that both the strip and the surface layer have a curvature against the substrate. As an alternative to this, it is conceivable that the band from the beginning, i.e. before the coating is provided with embossed grooves in which you can cut without risk. The embossments in the steel strip coated surface do not have to be limited to future places for cutting, but it is also possible to imagine a surface provided with channels, either for aesthetic reasons or for transport of refrigerant and / or lubricant.

With the help of the invention it becomes possible to t.o.m. use surfaces of so-called rubber diamond (carbon nitride) in a number of applications where this has previously been completely impossible to imagine. Although it is essential that the substrate of the PVD layer is hard, it is conceivable that the material is formed even after the coating, for example by bending into circular shapes with the wear surface either facing outwards or inwards depending on the purpose.

In cases where a dull storage is desired: a very thin adhesive is used while in other cases a certain elasticity may be desired for the storage as a whole, whereby the adhesive layer may be thicker and elastic, for example foam-marbled.

Claims (14)

10 15 20 25 30 513 219 6 PATENT REQUIREMENTS Method for producing a hard wear surface of PVD material on a soft surface, characterized in that a piece of sheet metal of harder material than the substrate by means of a PVD method on one side is coated with a PVD layer which in turn is harder than the metal sheet and that the sheet or parts of it are then glued with their side facing away from the PVD coating fixed where the wear surface is desired on the softer surface. Method for producing a hard wear surface of PVD material on a large object, characterized in that a piece of sheet metal of hard material is coated by means of a PVD method on one side with a PVD layer which in turn is harder than the metal plate and then gluing the plate or parts thereof with its side facing away from the PVD coating fixed where the wear surface is desired on the intended object. Method according to Claim 1 and / or 2, characterized in that the plate has the shape of an elongate strip. Method according to one of the preceding claims, characterized in that the PVD coating consists of several layers. Method according to one of the preceding claims, characterized in that the surface of the plate facing the PVD coating is hardened or plated before the PVD coating is applied in order to obtain the required hardness. Method according to one of the preceding claims, characterized in that the surface of the plate facing away from the PVD layer is coated with adhesive so that the plate becomes self-adhesive. Method according to one of the preceding claims, characterized in that parts of the desired shape are punched out of the material, in particular in such a way that the degree arising during the punching is turned away from the coated surface. Method according to one of the preceding claims, characterized in that the sheet material is bent, bent or embossed to the desired shape before or after the coating. Method according to claims 6 and 8, characterized in that the adhesive surface is provided with protective release paper or the like so that shaping in tools can take place after the application of the adhesive. 10. lO. Wear part, characterized in that it consists of a steel plate or equivalent which is coated on one side with a PVD coating and on the other side with an adhesive plate. 11. ll. Wear part according to claim 10, characterized in that it comprises a substrate consisting of a sheet, which in itself is hard, surface hardened or plated. Wear part according to Claim 10 or 11, characterized in that the plate on its PVD coating is coated on an opposite side with a self-adhesive glue, which is optionally covered by a protective paper until the application. Wear part according to claim 10, 11 or 12, characterized in that the plate has the shape of a strip or strip, for example in the form of a roller, Wear part according to one or more of Claims 10 to 13, characterized in that an even harder PVD layer is applied to its hardened or hardened surface, for example carbon nitride (rubber diamond) or diamond-like carbon (DLC), optionally with metal inclusions.