METHOD FOR PRODUCING A GREEN COMPOSITION AND METHOD FOR FURTHER PROCESSING THE GREEN COMPOSITION INTO A MACHINING SEGMENT

Description

Technisches Gebiet

[0001] The present invention relates to a method for producing a green compact according to the preamble of claim 1 and to a method for further processing the green compact into a processing segment according to the preamble of claim 6. Stand der Technik

[0002] Machining tools, such as core drill bits, saw blades, stock removal discs, and abrasive chains, comprise machining segments that are attached to a tubular, disc-shaped, or ring-shaped base body. The machining segments are connected to the base body by welding, soldering, or gluing. Depending on the machining process of the machining tool, machining segments used for core drilling are called drilling segments; machining segments used for sawing are called sawing segments; machining segments used for removal are called stock removal segments; and machining segments used for cutting are called cutting segments.

[0003] Machining segments for core drill bits, saw blades, abrasive discs, and abrasive chains are manufactured from a matrix material and hard material particles. The hard material particles can be randomly distributed or arranged according to a defined particle pattern within the matrix material. For machining segments with randomly distributed hard material particles, the matrix material and the hard material particles are mixed, the mixture is poured into a suitable tool mold, and further processed into the machining segment. For machining segments with defined arrangement of hard material particles, a green compact is built up layer by layer from matrix material, into which the hard material particles are arranged according to the defined particle pattern.For machining segments that are to be welded to the base body of the machining tool, a structure consisting of a machining zone and a neutral zone has proven to be effective, as some combinations of matrix material and base body are not weldable. The machining zone is constructed from a first matrix material, and the neutral zone from a second matrix material that is different from the first matrix material and weldable to the base body.

[0004] In machining tools, which can be designed as core drill bits, saw blades, removal discs or cutting-off chains and are intended for the wet or dry machining of concrete materials, increased wear can occur on the side surfaces of the machining segments due to friction with the substrate. The wear depends in particular on the wear properties of the first matrix material. EP 1 295 928 B1 discloses reducing wear on the side surfaces of the machining segments by means of second hard material particles which are mixed into the first matrix material as statistically distributed hard material particles. A disadvantage is that the second hard material particles are completely embedded in the first matrix material. In order to expose the second hard material particles on the side surfaces, the machining segments must be sharpened on the side surfaces.

[0005] EP 0 754 106 A1 discloses a known method for producing a machining segment from a first matrix material, first hard material particles and second hard material particles which are arranged according to a defined particle pattern.

[0006] US 5,203,880 A discloses a known method for producing a green compact for a machining segment from a first matrix material and first hard material particles arranged according to a defined first particle pattern. The first matrix material is applied to the tool mold, the first hard material particles are arranged in the first matrix material according to the defined particle pattern, and the support material is then placed between the green compact and the tool mold. Darstellung der Erfindung

[0007] The object of the present invention is to develop a method for producing a green compact for a machining segment, with which machining segments can be produced that exhibit low wear on the side surfaces of the machining segments. Conventional tool components are to be used both in the production of the green compact and in the further processing of the green compact into the machining segment; the use of special tool components is to be avoided. Furthermore, no post-processing of the machining segments on the side surfaces is to be required.

[0008] This object is achieved according to the invention in the method mentioned at the outset by the features of independent claim 1. Advantageous further developments are specified in the dependent claims.

[0009] The method for producing a green compact for a machining segment from a powdered or granular first matrix material, first hard material particles and second hard material particles is characterized according to the invention by the steps: ▪ Applying a lower layer of a powdered or granular support material that is different from the first matrix material, ▪ Arranging the second hard material particles according to a defined second particle pattern in the lower layer, wherein the second hard material particles are partially embedded in the support material, ▪ Carrying out a sequence of a first step and a second step that is carried out N times, N ≥ 1, wherein in the first step a matrix layer is applied from a first region, wherein the first matrix material is applied in the first region, and in the second step the first hard material particles are arranged according to a defined first particle pattern in the matrix layer, ▪ Arranging the second hard material particles according to the defined second particle pattern in the Nth matrix layer, wherein the second hard material particles are partially embedded in the first matrix material, and ▪ Applying an upper layer of the support material,wherein the second hard material particles are completely covered by the support material.

[0010] The inventive method for producing a green compact is characterized by the fact that the green compacts are constructed horizontally, i.e., the construction direction runs perpendicular to the height direction between the underside and top of the processing segment. In the horizontal construction, the particle layers of the green compact differ from the superimposed particle layers of the finished processing segment. The protrusion of the second hard material particles on the side surfaces of the processing segments is created using the powdered or granular support material, which is different from the first matrix material.

[0011] The term "support material" encompasses all materials used to construct machining segments into which hard material particles can be embedded. The support material is in powder or granular form and is different from the primary matrix material. It serves to completely embed the hard material particles in the powder or granular material.

[0012] During the construction of the green compact, the second hard material particles are arranged in the first matrix material and the support material so that the second hard material particles are completely embedded in powder or granular material. Since the second hard material particles in the green compact are completely embedded in powder or granular material, conventional press dies can be used to compact the green compact by cold or hot pressing or to further process it into the machining segment by hot pressing.

[0013] Green compacts produced using the method for producing a green compact according to the invention can be further processed into processing segments using known methods for further processing the green compact. Known further processing methods include compacting the green compact by cold pressing or hot pressing into a compact, which is then further processed into the processing segment by free-form sintering or hot pressing, or further processing the green compact by free-form sintering or hot pressing into the processing segment.

[0014] In a preferred embodiment, the first hard material particles are arranged in the first matrix material according to the defined first particle pattern. The method according to the invention for producing a green compact is suitable for constructing machining segments comprising multiple particle layers. During machining, worn first hard material particles are removed and new, deeper-lying first hard material particles are exposed.

[0015] In an alternative preferred embodiment, the matrix layer is applied from the first region and a second region, wherein the support material is applied in the second region and the first hard material particles are arranged in a transition region between the first region and the second region. The method according to the invention for producing a green compact is suitable for the construction of processing segments that have a particle layer on the upper side. These processing segments, which have first hard material particles with a large overhang on the upper side, are used in particular for the dry processing of concrete materials.

[0016] Particularly preferably, a support material with a melting temperature higher than the sintering temperature of the first matrix material is applied to the second region of the matrix layer. If the melting temperature of the support material is higher than the sintering temperature of the first matrix material, the support material remains in its powder or granular state during heating and can be easily removed from the finished machining segment after the sintering process.

[0017] Alternatively, a support material with a melting temperature lower than the sintering temperature of the first matrix material is applied to the second region of the matrix layer. If the melting temperature of the support material is lower than the sintering temperature of the first matrix material, the support material changes from its powder or granular state upon heating and liquefies before the first matrix material sinters. The liquid support material can disperse in the first matrix material and support the sintering process as an infiltrate.

[0018] The invention further relates to a method for further processing a green compact produced using the method for producing a green compact into a machining segment, which is connected via a bottom side to a base body of a machining tool. In a green compact produced using the method for producing a green compact according to the invention, the second hard material particles have no projection on the side surfaces. The projection of the second hard material particles on the side surfaces is created during further processing of the green compact into the machining segment.

[0019] In a first embodiment, the green compact is compressed into a pellet under pressure, which is then further processed into a processing segment. The green compact is compressed into a pellet under pressure between a first press die, which forms a first side surface of the processing segment, and a second press die, which forms a second side surface of the processing segment.

[0020] Particularly preferably, the compact is further processed into the machining segment by free-form sintering or hot pressing. Since the second hard material particles in a green compact produced according to the invention are completely embedded in powder or granular material, conventional press dies can be used during hot pressing to form the side surfaces of the machining segment.

[0021] In a second embodiment, the green compact is further processed into the machining segment by free-form sintering or hot pressing. Since the second hard material particles in a green compact produced according to the invention are completely embedded in powder or granular material, conventional press dies can be used during hot pressing to form the side surfaces of the machining segment. Ausführungsbeispiele

[0022] Embodiments of the invention are described below with reference to the drawing. These are not necessarily intended to represent the embodiments to scale; rather, where useful for explanation, the drawing is schematic and / or slightly distorted. It should be noted that numerous modifications and changes to the form and detail of an embodiment can be made without deviating from the general idea of the invention. The general idea of the invention is not limited to the exact form or detail of the preferred embodiment shown and described below, or to an object that would be limited compared to the object claimed in the claims. For given dimensioning ranges, values lying within the stated limits are also intended to be disclosed as limit values and can be used and claimed as desired.For the sake of simplicity, the same reference numerals are used below for identical or similar parts or parts with identical or similar functions.

[0023] They show: FIGS. 1A, B two variants of a machining tool designed as a core drill bit; FIGS. 2A, B two variants of a machining tool designed as a saw blade; FIG. 3 a machining tool designed as a removal disc; FIG. 4 a machining tool designed as a cutting-off chain; FIGS. 5A-C a green compact ( FIG. 5A ), which is compressed into a pellet ( FIG. 5B ) and is further processed into a processing segment ( FIG. 5C ); FIG. 6A-Ethe production of the green body of the FIG. 5A by means of the method according to the invention for producing a green compact; FIG. 7A, green compact ( FIG. 7A ), which is further processed into a processing segment ( FIG. 7B ); and FIGS. 8A-F the production of the green body of the FIG. 7A by means of the method according to the invention for producing a green compact.

[0024] FIGN. 1A , B show two variants of a core drilling crown 10A, 10B The machining tool designed in FIG. 1A The core drill bit 10A shown is referred to as the first core drill bit and the one shown in FIG. 1B The core drilling crown 10B shown is referred to as the second core drilling crown; moreover, the first and second core drilling crowns 10A, 10B are summarized under the term "core drilling crown".

[0025] The first core drill bit 10A comprises several machining segments 11A, a tubular base body 12Aand a tool holder 13A. The machining segments 11A, which are used for core drilling, are also referred to as drill segments, and the tubular base body 12A is also referred to as the drill shaft. The drill segments 11A are firmly connected to the drill shaft 12A, for example, by screwing, gluing, soldering, or welding.

[0026] The second core drill bit 10B comprises an annular machining segment 11B, a tubular base body 12B and a tool holder 13B. The annular machining segment 11B, which is used for core drilling, is also referred to as the drill ring, and the tubular base body 12B is also referred to as the drill shaft. The drill ring 11B is firmly connected to the drill shaft 12B, for example, by screwing, gluing, soldering, or welding.

[0027] The core drilling crown 10A, 10B is connected to a core drilling machine via the tool holder 13A, 13B and is rotated by the core drilling machine in one direction of rotation 14 around an axis of rotation 15 During the rotation of the core drill bit 10A, 10B around the rotation axis 15, the core drill bit 10A, 10B is moved along a feed direction 16 into a workpiece to be machined, with the feed direction 16 running parallel to the rotation axis 15. The core drilling crown 10A, 10B creates a drill core and a drill hole in the workpiece to be machined.

[0028] The drill shaft 12A, 12B is in the embodiment of the FIGN. 1A , B are formed in one piece and the drill segments 11A or the drill ring 11B are firmly connected to the drill shaft 12A, 12B. Alternatively, the drill shaft 12A, 12B can be formed in two parts from a first drill shaft section and a second drill shaft section, wherein the drill segments 11A or the drill ring 11B are firmly connected to the first drill shaft section and the tool holder 13A, 13B is firmly connected to the second drill shaft section. The first and second drill shaft sections are connected to one another via a detachable connecting device. The detachable connecting device is designed, for example, as a plug-and-turn connection, as described in EP 2 745 965 A1 or EP 2 745 966 A1. The design of the drill shaft as a one-piece or two-piece drill shaft has no influence on the structure of the drill segments 11A or the drill ring 11B.

[0029] FIGN. 2A , B show two variants of a saw blade 20A, 20B The machining tool developed in FIG. 2A The saw blade 20A shown will be referred to as the first saw blade and the one shown in FIG. 2B The saw blade 20B shown is referred to as the second saw blade, and the first and second saw blades 20A, 20B are collectively referred to as the "saw blade".

[0030] The first saw blade 20A comprises several machining segments 21A, a disc-shaped base body 22A and a tool holder. The processing segments 21A, which are used for sawing, are also referred to as saw segments, and the disc-shaped base body 22A is also referred to as the base blade. The saw segments 21A are firmly connected to the base blade 22A, for example, by screwing, gluing, soldering, or welding.

[0031] The second saw blade 20B comprises several machining segments 21B, a ring-shaped base body 22Band a tool holder. The machining segments 21B, which are used for sawing, are also referred to as saw segments, and the ring-shaped base body 22B is also referred to as a ring. The saw segments 21B are firmly connected to the ring 22B, for example, by screwing, gluing, soldering, or welding.

[0032] The saw blade 20A, 20B is connected to a saw via the tool holder and is rotated by the saw in one direction during sawing operation 24 around an axis of rotation 25 During the rotation of the saw blade 20A, 20B about the rotation axis 25, the saw blade 20A, 20B is moved along a feed direction, wherein the feed direction runs parallel to the longitudinal plane of the saw blade 20A, 20B. The saw blade 20A, 20B creates a saw slot in the workpiece to be machined.

[0033] FIG. 3 shows a removal disc 30designed machining tool. The removal disk 30 comprises several machining segments 31, a basic body 32 and a tool holder. The machining segments 31, which are used for removal, are also referred to as removal segments, and the disc-shaped base body 32 is also referred to as a cup. The removal segments 31 are firmly connected to the cup 32, for example, by screwing, gluing, soldering, or welding.

[0034] The removal disc 30 is connected to a tool device via the tool holder and is rotated by the tool device in one direction of rotation during removal operation 34 around an axis of rotation 35 driven. During the rotation of the removal disk 30 about the rotation axis 35, the removal disk 30 is moved over a workpiece to be machined, with the movement running perpendicular to the rotation axis 35. The removal disk 30 removes the surface of the workpiece to be machined.

[0035] FIG. 4 shows a cutting chain 40 trained processing tool. The cutting chain 40 comprises several processing segments 41, several limb-shaped basic bodies 42 and several connecting links 43. The processing segments 41, which are used for cutting, are also referred to as cutting segments and the link-shaped base bodies 42 are also referred to as drive links.

[0036] The drive links 42 are connected via connecting links 43. In the exemplary embodiment, the connecting links 43 are connected to the drive links 42 via rivet bolts. The rivet bolts enable rotation of the drive links 42 relative to the connecting links 43 about a rotation axis that runs through the center of the rivet bolts. The machining segments 41 are firmly connected to the drive links 42, for example, by screwing, gluing, soldering, or welding.

[0037] The cutting-off chain 40 is connected to a tool via a tool holder and, during operation, is driven by the tool in one direction of rotation. As the cutting-off chain 40 rotates, the cutting-off chain 40 is moved into the workpiece to be machined.

[0038] The production of a machining segment 51, which has low wear on the side surfaces, is carried out by means of the inventive method for producing a green compact and the method for further processing the green compact into a processing segment. In a first step, a green compact 52 manufactured, in a second stage the green body 52 is turned into a pressed part 53 compacted, and in a third stage, the compact 53 is further processed into the processing segment 51. Alternatively, a green compact can be produced in a first stage, which is further processed into the processing segment in a second stage.

[0039] FIGN. 5A-C show the greenling 52 ( FIG. 5A ), the pellet 53 ( FIG. 5B ) and the processing segment 51 ( FIG. 5C ). The machining segment 51 consists of a machining zone 54 and a neutral zone 55 The neutral zone 55 is required if the machining segment 51 is to be welded to the base body of a machining tool and the combination of matrix material and base body is not weldable; for weldable combinations of matrix material and base body, the neutral zone 55 can be omitted.

[0040] The processing zone 54 is made of a powder or granular first matrix material 56, first hard material particles 57, which are arranged according to a defined first particle pattern, and second hard material particles 58,which are arranged according to a defined second particle pattern, and the neutral zone 55 is made of a powder or granular second matrix material 59 The term "matrix material" encompasses all materials used to construct machining segments into which hard material particles can be embedded. Matrix materials can consist of a single material or be a mixture of different materials. The term "hard material particles" encompasses all cutting media for machining segments; these primarily include individual hard material particles, composite parts made up of multiple hard material particles, and coated or encapsulated hard material particles.

[0041] Machining segment 51 corresponds in structure and composition to machining segments 11A, 21A, 21B, 31, 41; machining segment 11B, designed as a drill ring, differs from machining segment 51 in its annular structure. The machining segments can differ from one another in their dimensions and surface curvatures. The structure of the machining segments is explained using machining segment 51 as an example and applies to machining segments 11A, 21A, 21B, 31, 41.

[0042] The machining segment 51 comprises the first and second hard material particles 57, 58, which are arranged in the first matrix material 56. The hard material particles of the machining segment 51 that machine a substrate are referred to as "first hard material particles," with the number of first hard material particles 57 and the defined first particle pattern being adapted to the requirements of the machining segment 51. Depending on the wear properties of the first matrix material 56, increased wear of the first matrix material 56 on the side surfaces of the machining segment 51 can occur during machining of a substrate with the machining segment 51 due to friction with the substrate. This wear is reduced by the second hard material particles 58.

[0043] The first and second hard material particles 57, 58 generally originate from particle distributions characterized by a minimum diameter, a maximum diameter, and an average diameter. In the exemplary embodiment of the FIGN. 5A-C The first hard material particles 57 originate from a first particle distribution with a first average diameter, and the second hard material particles 58 originate from a second particle distribution with a second average diameter, wherein the first average diameter is larger than the second average diameter. Alternatively, the first and second hard material particles 57, 58 can originate from the same particle distribution and have the same average diameter.

[0044] The processing segment 51 is provided with a bottom 61 connected to the base body of a machining tool. FIG. 5C In the processing segment 51 shown, the first hard material particles 57 are arranged in several particle layers in the first matrix material 56 according to the defined first particle pattern, and the second hard material particles 58 are arranged according to the defined second particle pattern on the side surfaces of the processing segment 51. The processing of the substrate is carried out via first hard material particles 57, which are arranged on an upper side opposite the underside 61 62 of the processing segment 51.

[0045] The FIG. 5A The green compact 52 shown is formed in a horizontal structure from the first matrix material 56, the first hard material particles 57, the second hard material particles 58, the second matrix material 59 and a powdered or granular support material 63The support material 63 is different from the first matrix material 56 and serves to cover the second hard material particles 58 during pressing. The state of the support material 63 is adapted to the state of the first matrix material 56, ie, with a powdered first matrix material 56, a powdered support material 63 is used, and with a granular first matrix material 56, a granular support material 63 is used.

[0046] The green body 52 is pressed between a first press die 64, which has a first side surface 65 forms, and a second press stamp 66, which has a second side surface 67formed, compacted, until the compact 53 essentially has the final geometry of the processing segment 51. The pressing direction of the first and second pressing rams 64, 66 runs between the first and second side surfaces 65, 67. Suitable methods for applying pressure to the green compact 52 include, for example, cold pressing or hot pressing. In cold pressing, the green compact 52 is subjected exclusively to pressure, whereas in hot pressing, in addition to pressure, the green compact 52 is exposed to temperatures of up to approximately 200°C.

[0047] The compact 53 is further processed into the processing segment 51 by free-form sintering or hot pressing. During free-form sintering, the compact 53 is subjected to temperature, while during hot pressing, it is subjected to pressure and temperature. If the compact 53 is further processed by free-form sintering, the green compact 52 is compacted until the compact 53 essentially has the final geometry of the processing segment 51. If the compact 53 is further processed by hot pressing, the compact 53 is further shaped during the hot pressing.

[0048] The properties of the support material 63, in particular the melting temperature T Schmelz , determine the behavior of the support material 63 during further processing. If the melting temperature T melt of the support material 63 is lower than the sintering temperature T Sinter of the first matrix material 76, the support material 63 changes its powdery or granular state upon heating and liquefies before the first matrix material 56 sinters; the liquid support material 63 can disperse in the first matrix material 76 during the sintering process and support the sintering process as an infiltrate. If the melting temperature T melt of the support material is higher than the sintering temperature T sinter of the first matrix material 56, the support material 63 remains in its powdery or granular state upon heating and can be easily removed from the finished machining segment after the sintering process.

[0049] FIGN. 6A-E show the production of the green compact 52 using the method according to the invention for producing a green compact. The green compact 52 is constructed from the first matrix material 56, the first hard material particles 57, the second hard material particles 58, the second matrix material 59, and the support material 63.

[0050] The production of the green compact 52 takes place in several steps: In a first step, a lower layer 71 of the support material 63 is applied, wherein the lower layer 71 can be applied in one layer or in several layers. In a second step, the second hard material particles 58 are arranged in the support material 63 according to the defined second particle pattern, wherein the second hard material particles 58 are not completely embedded in the support material 63, but have a projection Δ below relative to the support material 63 ( FIG. 6A ).

[0051] After the second hard material particles 58 have been arranged, the first and second matrix materials 56, 59 are applied and the first hard material particles 57 are arranged in the first matrix material 56 in a sequence of a third and fourth step (first and second subsequent step), whereby the sequence can be carried out once or multiple times (N-fold with N ≥ 1). In the first subsequent step, a matrix layer 72 from a first area 73 and a second area 74 applied, wherein the first matrix material 56 is applied in the first region 73 and the second matrix material 59 is applied in the second region 74; in the case of a green body without a neutral zone, the second region 74 is omitted. In the second subsequent step, the first hard material particles 57 are arranged in the first matrix material 56 according to the defined first particle pattern ( FIG. 6B ). In the Greenling 52, the sequence of the first and second steps is carried out three times. FIG. 6C shows the greenie 52 after the third episode.

[0052] After the first hard material particles 57 have been arranged in the third matrix layer, an upper matrix layer 76 from a first area 77 and a second area 78 applied, wherein the first matrix material 56 is applied in the first region 77 and the second matrix material 59 is applied in the second region 78. The second hard material particles 58 are arranged in the upper matrix layer 76 according to the defined second particle pattern, wherein the second hard material particles 58 are partially embedded in the first matrix material 56 and have a projection Δ above the first matrix material 56 ( FIG. 6D Finally, an upper layer 79 of the support material 63, wherein the second hard material particles 58 are completely covered by the support material 63 ( FIG. 6E ).

[0053] FIGN. 7A , Bshow a processing segment 81, which was produced using the method according to the invention for producing a green compact and the method for further processing the green compact into the processing segment. The processing segment 81 is produced in two stages: In a first stage, a green compact 82 manufactured ( FIG. 7A ) and in a second stage the green body 82 is further processed into the processing segment 81 ( FIG. 7B ).

[0054] The processing segment 81 differs from the processing segment 51 of the FIG. 5C in that the machining segment 81 consists of a machining zone 84 and has no neutral zone. The processing zone 84 is made of a powder or granular first matrix material 86, first hard material particles 87, which are arranged according to a defined first particle pattern, and second hard material particles 88,which are arranged according to a defined second particle pattern.

[0055] The first hard material particles 87 and second hard material particles 88 generally originate from particle distributions that are characterized by a minimum diameter, a maximum diameter, and an average diameter. In the exemplary embodiment of the FIGN. 7A , B, the first hard material particles 87 originate from a first particle distribution with a first average diameter, and the second hard material particles 88 originate from a second particle distribution with a second average diameter, wherein the first average diameter is larger than the second average diameter. Alternatively, the first hard material particles 87 and the second hard material particles 88 can originate from the same particle distribution and have the same average diameter.

[0056] The processing segment 81 is provided with a bottom 91connected to the base body of a machining tool. The machining of a substrate is carried out by first hard material particles 87, which are arranged on an upper side opposite the underside 91 92 are arranged. In the finished machining segment 81, the first hard material particles 87 have a projection Δ relative to the first matrix material 86.

[0057] The green compact 82 is produced analogously to the production of the green compact 52, whereby the application of the second matrix material is omitted. The green compact 82 is constructed from the first matrix material 86, the first hard material particles 87, the second hard material particles 88, and a powdered or granular support material 93. The support material 93 is different from the first matrix material 86 and serves to cover the first hard material particles 87 on the upper side 92. The state of the support material 93 is adapted to the state of the first matrix material 86, i.e., for a powdered first matrix material 86, a powdered support material 93 is used, and for a granular first matrix material 86, a granular support material 93 is used.

[0058] FIGN. 8A-F show the production of the green compact 82 using the method according to the invention for producing a green compact. The green compact 82 is constructed from the first matrix material 86, the first hard material particles 87, which are arranged according to the defined first particle pattern, the second hard material particles 88, which are arranged according to the defined second particle pattern, and the support material 93.

[0059] The production of the green body 82 starts with a lower layer 101 of the support material 93 is applied and the second hard material particles 88 are arranged in the support material 93 according to the defined second particle pattern, wherein the second hard material particles 88 are not completely embedded in the support material 93, but have a projection Δ below relative to the support material 93 ( FIG. 8A ).

[0060] After the second hard material particles 88 have been arranged, the first matrix material 86 and the support material 93 are applied, as well as the first hard material particles 87 are arranged in the first matrix material 86 in a sequence of a first and second step, which can be carried out once or multiple times (N-fold with N ≥ 1). In the first step of the sequence, a matrix layer 102 from a first area 103 and a second area 104 applied, wherein the first matrix material 86 is applied in the first region 103 and the support material 93 is applied in the second region 104 ( FIG. 8B ), and in the second step of the sequence, the first hard material particles 87 are arranged in the matrix layer 102 according to the defined first particle pattern, wherein the first hard material particles 87 are arranged in a transition region 105 between the first area 103 and the second area 104 ( FIG. 8C ). In the case of the green 82, the sequence of the first and second steps is carried out twice, FIG. 8D shows the greenling 82 after the second episode.

[0061] After the first hard material particles 87 have been arranged in the second matrix layer 102, the second hard material particles 88 are arranged in the second matrix layer 102 according to the defined second particle pattern, wherein the second hard material particles 88 are partially embedded in the first matrix material 86 and have a projection Δ above the first matrix material 86 ( FIG. 8E Finally, an upper layer 109 of the support material 93, wherein the second hard material particles 88 are completely covered by the support material 93 ( FIG. 8F ).

Claims

1. Method for producing a green body (52; 82) for a machining segment (11A, 11B; 21A, 21B; 31; 41; 51; 81) from a powdered or granular first matrix material (56; 86), first hard material particles (57; 87) and second hard material particles (58; 88), wherein the machining segment is connected by a bottom side (61; 91) to a basic body (12A, 12B; 22A, 22B; 32; 42) of a machining tool (10A, 10B; 20A, 20B; 30; 40) and has at the side surfaces a projection (Δ) of the second hard material particles (58; 88), characterized by the steps of: ▪ applying a lower layer (71; 101) of a powdered or granular supporting material (63; 93), which is different from the first matrix material (56; 86), ▪ arranging the second hard material particles (58; 88) in the lower layer (71; 101) according to a defined second particle pattern, wherein the second hard material particles (58; 88) are partially embedded in the supporting material (63; 93), ▪ performing a sequence of a first and a second sequence step, which is performed N times (N ≥ 1), wherein, - in the first sequence step, a matrix layer (72; 102) composed of a first region (73; 103) is applied, wherein the first matrix material (56; 86) is applied in the first region (73; 103), and, - in the second sequence step, the first hard material particles (57; 87) are arranged in the matrix layer (72; 102) according to a defined first particle pattern, ▪ arranging the second hard material particles (58; 88) in the Nth matrix layer according to the defined second particle pattern, wherein the second hard material particles (58; 88) are partially embedded in the first matrix material (56; 86), and ▪ applying an upper layer (79; 109) of the supporting material (63; 93), wherein the second hard material particles (58; 88) are completely covered by the supporting material (63; 93).

2. Method according to Claim 1, characterized in that the first hard material particles (57) are arranged in the first matrix material (56) according to the defined first particle pattern.

3. Method according to Claim 1, characterized in that the matrix layer (102) composed of the first region (103) and a second region (104) is applied, wherein the supporting material (93) is applied in the second region (104), and the first hard material particles (87) are arranged in a transition region (105) between the first region (103) and the second region (104).

4. Method according to Claim 3, characterized in that a supporting material (93) with a melting temperature which is higher than the sintering temperature of the first matrix material (86) is applied in the second region (104) of the matrix layer (102).

5. Method according to Claim 3, characterized in that a supporting material (93) with a melting temperature which is lower than the sintering temperature of the first matrix material (86) is applied in the second region (104) of the matrix layer (102).

6. Method for further processing the green body (52; 82) produced using the method for producing a green body according to one of Claims 1 to 5, to form a machining segment (51; 81).

7. Method according to Claim 6, characterized in that the green body (52) is compacted under the action of pressure to form a compact body (53), and the compact body (53) is then processed further to form the machining segment (51).

8. Method according to Claim 7, characterized in that the compact body (53) is processed further to form the machining segment (51) by free-form sintering or hot pressing.

9. Method according to Claim 6, characterized in that the green body (82) is processed further to form the machining segment (81) by free-form sintering or hot pressing.