EP1109648A1

EP1109648A1 - Method for producing a cutting plate for the chip-cutting machining of metallic tools

Info

Publication number: EP1109648A1
Application number: EP99931243A
Authority: EP
Inventors: Werner Stief
Original assignee: Mapal WWS Werner Stief GmbH
Current assignee: Mapal WWS Werner Stief GmbH
Priority date: 1998-07-04
Filing date: 1999-07-02
Publication date: 2001-06-27
Also published as: HU222000B1; HUP0103594A2; TR200003805T2; YU83700A; IL140548A0; NO20010010L; CN1308568A; AU4781399A; SK42001A3; DE19829924B4; WO2000001508A1; CA2336843A1; JP2002519207A; HUP0103594A3; ZA200100059B; PL345188A1; BR9911816A; NO20010010D0; DE19829924A1; CZ200127A3

Abstract

The invention relates to a method for producing a cutting plate for the chip-cutting machining of metallic workpieces, comprising the following steps: application of a powder layer containing crystals of diamond and/or cubic boron nitride or such like on a metal plate, preferably a hard metal plate; sintering of the powder layer on the metal plate; and grinding of at least one lateral face of the coated metal plate to produce at least one cutting edge. In a first step a cutting plate blank without cutting edge is produced. In a subsequent second step the cutting plate blank in the region in which the cutting plate(s) are to be situated is given a desired shape appropriate for the intended application. In this region the plate is then ground to produce at least one cutting edge.

Description

Process for producing a cutting insert used for machining metal tools

description

The invention relates to a method for producing a cutting insert for machining metal workpieces according to the preamble of claim 1, also a cutting insert blank according to the preamble of claim 6 and a cutting insert according to the preamble of claim 9.

Cutting plates for machining metallic workpieces and methods for their production are known. In the following, it is assumed here by cutting inserts, which have a metallic _G around carrier, for example a metal plate, and a crystalline connected thereto, wear-resistant layer. The wear-resistant _S chicht comprises crystals of diamond (polycrystalline slide ant / PCD) and / or cubic boron nitride (CBN). This layer is applied to the base layer, which is preferably made of hard metal, and then in a sintering process is connected practically permanently to the metallic carrier. It is known to play ^¬, the powder layers is here ^¬ sprochenen type at 1500 ° C and at 50 to 60 kbar connect to the cemented carbide substrate to. A side surface of the metal plate provided with the wear-resistant layer is then ground to produce a cutting edge. In the case of cutting inserts with multiple cutting edges, a corresponding number of side faces are subjected to a grinding process.

In the known method described here, the coated metal plate is either produced directly in the form that the later cutting plate is to have. However, it is also known to produce larger metal plates, which are also referred to as round blanks, in the method described here and to cut or cut cutting plates and then to subject the resulting side faces to a grinding process in the areas in which the later cutting edge is desired .

This process is relatively expensive and complex in terms of storage.

It is therefore an object of the invention to provide a method of the type mentioned at the outset which does not have these disadvantages.

To achieve this object, a method is proposed which comprises the steps mentioned in claim 1. The process is characterized in that in a first process step an insert blank is produced which does not yet have its final shape. It is particularly in the area where the finished insert one or more cutting edges are not yet specifically designed. In order to be able to use such an insert blank as an insert, it is first necessary to bring the specific area mentioned here into the desired shape in a later second process section, which is adapted to a specific application. For example, an initially rectangular end region of the insert blank is triangular or provided with a tip in order to be able to implement a thread turning tool. The shaping of the area of the insert blank provided for the machining can take place in any suitable manner. Only then is the cutting plate blank processed in this way ground in the area of the later cutting edges.

Immediately after its manufacture, the insert blank is not yet suitable for use in the machining of metallic workpieces. This initially presents itself as a disadvantage because the finished cutting insert can now only be produced in a second, further process step, the area in which the cutting edge (s) should lie still require special processing and a desired one Form must be brought before the cutting edges can be produced by machining the side surfaces. It has been found, however, that insert blanks of the type mentioned here are produced in large numbers and without further specification an intermediate bearings can be supplied. To produce a special cutting plate, any blanks can be picked from the stock of non-specific cutting plate blanks, which are then brought into the desired shape in the final processing and provided with at least one cutting edge by means of a grinding process.

An embodiment of the method is preferred, which is characterized in that the cutting insert blank is brought into its desired shape by a grinding process in the area in which the at least one cutting edge is to lie. With a suitable execution of the grinding process, the processing of this area can be carried out in such a way that the grinding of the side surfaces thus created can be carried out directly on the shape in order to produce at least one cutting edge. It is thus possible to combine the additional second process section with the grinding process for producing a cutting edge and to minimize the processing time required for producing the cutting insert.

Further forms of the procedure result from the remaining subclaims.

It is also an object of the invention to provide a blank insert which is used to produce a insert and which is characterized by cost-effective manufacture. To achieve this object, a blank insert is proposed which has the features mentioned in claim 6 and which is characterized in that it initially has an unspecific shape. It is therefore not tailored to a specific machining method or designed for special tools. The storage of such a non-specific blank does not require any special organizational structure and is therefore easy and inexpensive to implement.

Further configurations of the insert blank result from the remaining subclaims.

The invention is explained below with reference to the drawing. Show it:

Figure 1 shows a cutting plate in plan view;

Figure 2 is a front view of the insert according to Figure 1 and

Figure 3 is a side view of the insert shown in Figure 1.

FIG. 1 shows a top view of a cutting insert 1 which has an essentially rectangular basic shape. One of the long sides, here the upper long side 3, is provided with elevations 5 and depressions 7, both of which are here, for example, essentially triangular and serve to provide a toothing which enables the cutting plate 1 to be securely anchored in a tool. By the provided here Similar design of the elevations 5 and depressions 7 over the course of the long side 3, it is possible to clamp the insert 1 in different positions in one tool and thus to ensure that the insert is reworked. So if the insert becomes blunt, it can be reworked so that it is re-clamped in the tool and can therefore continue to be used.

The cutting insert 1 is made from a cutting insert blank 9 which essentially has the outer contour of the cutting insert 1, but which is initially of essentially rectangular shape in the region 11 in which the cutting edges 13 and 15 of the cutting insert 1 lie. This is illustrated in FIG. 1 by a dashed line.

In the exemplary embodiment of the cutting plate 1 shown here, the cutting edges 13 and 15 are arranged symmetrically to an imaginary center line 17 in the region 11 and, for example, enclose an angle of approximately 30 ° therewith. A dotted line 19 indicates that a continuous cutting edge 13 'extending over the entire height h of the cutting plate 1 can also be provided, which here includes an angle of approximately 40 ° with the center line 17 purely by way of example. Of course, it is conceivable that this cutting edge 13 'also runs in mirror image to the center line 17. From the explanations given here it is readily apparent that an essentially rectangular region 11 of a cutting plate blank 9 can be machined in such a way that cutting edges matched to special machining methods are realized.

FIG. 2 shows a front view of the cutting insert 1, that is to say a view of the region 11.

This illustration clearly shows that the cutting plate 1 has a metallic base support, here a metal plate 21, preferably hard metal plate, onto which a hard material layer, namely a powder layer 23, is sintered practically inseparably, which comprises crystals of diamond and / or of cubic boron nitride or the like . This layer is particularly hard, wear-resistant and resistant and is shown in dotted lines for clarity.

In the exemplary embodiment of the cutting insert 1 shown here, a bevel 27 is provided on the underside 25 opposite the powder layer 23, which serves for the defined contact of the cutting insert 1 with a tool.

The side surface 29 lying at the bottom in FIG. 2 is inclined with respect to an imaginary center plane E. It falls here from the surface 31 of the powder layer 23 to the central plane E at an acute angle of, for example, 6 °. The top side flat 33, which corresponds to the long side 3 (FIG. 1), runs parallel to the central plane E.

From the top view, the front side surfaces 35 and 37 lying in the region 11 can be seen, which are subjected to a grinding process in order to produce the cutting edges 13 and 15. The illustration according to FIG. 2 shows that the front side surfaces 35 and 37 intersect in the region of the central plane E, that is to say they are symmetrical.

The side view according to FIG. 3 shows the longitudinal side 3 of the side plate 1 lying on top in FIG. 1. Elements of the cutting plate 1 addressed in FIGS. 1 and 2 are provided with the same reference numbers here, so that reference is made to the description of FIGS. 1 and 2.

The illustration according to FIG. 3 clearly shows that the longitudinal side 3 is provided with elevations 5 and depressions 7 which extend over the entire thickness d of the cutting insert 1 and run essentially parallel to the rear side 39 of the cutting insert 1.

It is also clear here that the insert 1 comprises a base support 21 and a powder layer 23 — also shown here in dotted lines.

Dashed lines also indicate that parts of a cutting plate blank 9 have been removed in the area 11 of the cutting plate 1 in order to form cutting edges in this area. In the following, the method for producing a cutting insert 1, which is used for machining metal workpieces, is discussed.

In a first method step, a powder layer comprising crystals of diamond and / or cubic boron nitride or the like is applied to a base support 21, namely to a metal plate, preferably a hard metal plate. The powder layer is sintered onto the base support 21 in a sintering process, for example at temperatures of 1500 ° C. and at a pressure of 50 to 60 kbar, an indissoluble connection being produced.

From the outset, the coated metal plate can have the shape of the cutting plate blank 9 mentioned in FIGS. 1 and 3. However, it is also possible to cut or cut cutting plate blanks 9 of the type mentioned here from a larger coated metal plate. The cutting process can be carried out by an erosion process, preferably by a wire erosion process. The elevations 5 and depressions 7 can already be provided in the region of the long side 3.

The area 11 of the insert blank is non-specific, that is, it is not specifically tailored to the later use of the insert 1. In the exemplary embodiment of a cutting insert blank 9 shown here, hen that this is substantially rectangular in area 11.

A cutting insert blank 9 of this type can be stored without any special effort, since it is not assigned to special tools.

If necessary, the area 11 of the insert blank 9 can be brought into a specific shape, so that the insert can be used as a chisel, turning tool for right or left rotation, threading insert (see FIG. 1) or also for a drill and / or for a reamer .

The area 11 of the insert blank 9 can be brought into the desired shape in a cutting and / or grinding process. In this way, side surfaces can be formed, at least one of which can then be subjected to a grinding process in order to produce at least one cutting edge.

After all, it is clear that because of the simple basic shapes of the insert blank 9, its manufacture is very easy to carry out. This is particularly true, of course, if a special configuration of a longitudinal edge, here the longitudinal edge 3, is dispensed with. The blank can therefore be produced particularly quickly and inexpensively. The storage of such a "neutral" blank can, as I said, also be implemented inexpensively. It finally turns out that the machining of the insert blanks 9 in the area 11 is particularly simple. The additional process step required to produce a cutting insert 1 can thus also be implemented quickly and inexpensively. The cutting blank in the area 11 can be shaped by a cutting and / or grinding method. In the latter method, it is particularly advantageous that the desired cutting edge can already be produced with the production of the desired shape, so that the additional outlay for producing the finished insert 1 from the insert blank 9 can be reduced to a minimum.

From what has been said above, it is clear that the insert 1 can be used generally, since virtually any desired cutting edge geometry can be realized in the region 11 of an insert blank 9. The blank 9 can be generally designed so that it can be used in any tools and for different machining methods. In order to enable the general implementation, the elevations 5 and depressions 7 shown in FIG. 1 can also be provided on other surfaces of the cutting plate 1. Finally, such configurations can also be dispensed with entirely in order to ensure the general use of the insert blank 9.

Finally, it should be noted that the insert 1 can be clamped directly into a tool. It is also possible to do this on one Solder the basic holder and then clamp it in a tool.

Claims

Expectations

1. The method for producing a machining of metal workpieces is a cutting insert, with the following steps:

Applying a powder layer comprising crystals of diamond and / or cubic boron nitride or the like to a metal plate, preferably a hard metal plate,

Sintering the powder layer onto the metal plate,

Grinding at least one side surface of the coated metal plate to produce at least one cutting edge,

characterized in that

in a first process step, a blank insert is produced without a cutting edge,

in a later second process step, the insert blank is brought into a desired shape adapted to the application in the area in which the insert (s) should lie, and that in this area the grinding process for producing at least one cutting edge is carried out.

2. The method according to claim 1, characterized in that the insert blank is cut out of the coated metal plate or cut off from this.

3. The method according to claim 2, characterized in that the cutting process is carried out by means of an erosion, preferably wire erosion process.

4. The method according to any one of claims 1 to 3, characterized in that the area in which the cutting edge (s) should lie (s) is brought into its desired shape by a cutting and / or grinding method.

5. The method according to any one of the preceding claims, characterized in that the metal plate is provided with a continuous powder layer.

6. Cutting insert blank for producing a cutting insert serving for the machining of metallic workpieces, characterized by a shape which is unspecific with respect to machining in the area in which the cutting edge (s) should lie.

7. Cutting insert blank according to claim 7, characterized in that it can be subjected to a cutting and / or grinding method in order to form the side surfaces, at least one of which can be ground to produce at least one cutting edge.

8. insert blank according to claim 7, characterized by at least one with elevations (5) and depressions (7) provided surface (long side (3)).

9. Cutting insert for the machining of metallic workpieces, produced by a method according to one of claims 1 to 5, characterized in that the cutting edge (s) is / are designed so that these as a chisel, turning tool, threading insert, as a cutting insert for one Drill and / or can be used for a reamer.