METHOD FOR LAYERED PRODUCTION OF A GREEN BODY FROM POWDERY OR PASTE-LIKE MATERIAL HAVING CUTTING ELEMENTS ARRANGED IN A DEFINED MANNER
20190381693 ยท 2019-12-19
Inventors
Cpc classification
B33Y10/00
PERFORMING OPERATIONS; TRANSPORTING
B28B1/008
PERFORMING OPERATIONS; TRANSPORTING
B28B1/001
PERFORMING OPERATIONS; TRANSPORTING
B33Y50/00
PERFORMING OPERATIONS; TRANSPORTING
C04B2235/6026
CHEMISTRY; METALLURGY
Y02P10/25
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
B29C64/165
PERFORMING OPERATIONS; TRANSPORTING
International classification
B28B1/00
PERFORMING OPERATIONS; TRANSPORTING
Abstract
A method for the layered production of a green body from powdery or paste-like material, including cutting elements based on three-dimensional data of the green body, the green body being segmented in a building direction into N (N2) consecutive cylindrical cross-sectional areas made up of a two-dimensional cross-sectional surface perpendicular to the building direction and a layer thickness in parallel to the building direction, including the method steps: the cross-sectional areas of the green body are each divided into material areas, and setting areas, in which the cutting elements are situated; the material areas in the building direction are applied to a building plane situated perpendicularly to the building direction, until at least one cavity formed by one setting area or by multiple consecutive setting areas in the building direction, has the necessary insert height for placing the cutting elements; and at least one cutting element is placed into the cavities having the necessary insert height for placing the cutting elements.
Claims
1-11. (canceled)
12: A method for the layered production of a green body from powdery or paste material, cutting elements being arranged in a defined manner and based on three-dimensional data of the green body, the green body being segmented in a building direction into N, N2, consecutive cylindrical cross-sectional areas made up of a two-dimensional cross-sectional surface perpendicular to the building direction and a layer thickness parallel to the building direction, the method comprising the steps of: dividing the cross-sectional areas of the green body each into material areas manufactured from the powdery or paste material and setting areas, the cutting elements being arranged in the setting areas; applying the material areas of one cross-sectional area or the material areas of multiple consecutive cross-sectional areas in the building direction to a building plane arranged perpendicularly to the building direction, until at least one cavity formed by one setting area or multiple consecutive setting areas in the building direction has a necessary insert height for placing the cutting elements; and placing at least one cutting element into the cavities having the necessary insert height for placing the cutting elements.
13: The method as recited in claim 12 wherein the necessary insert height of the cavities for placing the cutting elements is less than a minimum diameter of the cutting elements.
14: The method as recited in claim 12 wherein the necessary insert height of the cavities for placing the cutting elements is greater than a maximum diameter of the cutting elements.
15: The method as recited in claim 12 wherein the cavities having the necessary insert height are filled not only with the cutting elements but also with a special material.
16: The method as recited in claim 15 wherein the filling of the cavities having the necessary insert height with special material is carried out in one method step.
17: The method as recited in claim 16 the filling of the cavities with the special material is carried out before placing the cutting elements.
18: The method as recited in claim 16 wherein the filling of the cavities with the special material is carried out after placing the cutting elements.
19: The method as recited in claim 15 wherein the filling of the cavities having the necessary insert height with the special material is carried out in two method steps, a first part of the special material being filled into the cavities before placing the cutting elements, the cutting elements being placed into the first part of the special material, and a second part of the special material being filled into the cavities after placing the cutting elements.
20: The method as recited in claim 13 wherein the cutting elements are at least partially fastened in the cavities with the aid of an adhesive.
21: The method as recited in claim 20 wherein the cavities having the necessary insert height are filled with the adhesive before placing the cutting elements.
22: The method as recited in claim 20 wherein the cutting elements are at least partially wetted with the adhesive before the cutting elements are placed into the cavities.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
[0030] Exemplary embodiments of the present invention are described below on the basis of the drawing. The latter is not necessarily intended to represent the exemplary embodiments true to scale but rather the drawing is presented in a schematic and/or slightly distorted form where useful for the purpose of explanation. It should be taken into account that a variety of modifications and changes relating to the form and detail of a specific embodiment may be undertaken without deviating from the general idea of the present invention. The general idea of the present invention is not limited to the exact form or the detail of the preferred specific embodiment illustrated and described below, nor is it limited to an object which would be limited in comparison to the object claimed in the claims. In given design areas, values within the specified limits are also to be disclosed as limiting values and be able to be arbitrarily used and claimed. For the sake of simplicity, the same reference numerals are used below for identical or similar parts or for parts having identical or similar functions.
[0031]
[0032]
[0033]
[0034]
[0035]
[0036]
[0037]
DETAILED DESCRIPTION
[0038]
[0039] To be able to manufacture first green body 10 in the layer structure, cuboid 10 is segmented in building direction 16 into five cylindrical cross-sectional areas 11 through 15, which are illustrated in
[0040] To distinguish between the material areas and the setting areas, the material areas of the ith cross-sectional area are referred to as ith material areas, and the setting areas of the ith cross-sectional area are referred to as ith setting areas. First cross-sectional area 11 includes a first material area 17, second cross-sectional area 12 includes a second material area 18 and five setting areas 19, third cross-sectional area 13 includes a third material area 21 and nine third setting areas 22, fourth cross-sectional area 14 includes a fourth material area 23 and four fourth setting areas 24, and fifth cross-sectional area 15 includes a fifth material area 25.
[0041]
[0042] During the layered construction of first green body 10, nine cavities are formed, into which cutting elements are placed. The nine cavities may be divided into a first group of five first cavities 26 and a second group of four second cavities 27. First cavities 26 are situated in second and third cross-sectional areas 12, 13 and are formed by second and third setting areas 19, 22 situated one above the other, second cavities 27 are situated in third and fourth cross-sectional areas 13, 14 and are formed by third and fourth setting areas 22, 24 situated one above the other.
[0043] In the exemplary embodiment of first green body 10, first and second cavities 26, 27 have the same cross-sectional shape and the same insert height. Alternatively, first cavities 26 may have a first cross-sectional shape and a first insert height, and second cavities 27 may have a second cross-sectional shape and a second insert height which are different from each other. Different cross-sectional shapes and/or different insert heights for the first and second cavities are useful if different first and second cutting elements are situated in the cavities.
[0044]
[0045] First green body 10 is manufactured in layers with the aid of a device, which includes a height-adjustable building plane 43, a powder feed unit and a print head. A first powder layer 44 of powdery material 41 having first layer thickness d.sub.1 is applied with the aid of the powder feed unit (
[0046] The insert height of first cavities 26 is reached after the application of the third powder and adhesive layers, and hard material particles 42 may be situated in first cavities 26. The insert height of first cavities 26 is referred to below as first insert height h.sub.1. In the exemplary embodiment, first insert height h.sub.1 is greater than maximum diameter D.sub.max of hard material particles 42. A first insert height h.sub.1, which is greater than maximum diameter D.sub.max of hard material particles 42, has the advantage that placed hard material particles 42 are almost completely situated in first cavities 26, and the risk of hard material particles 42 being displaced during the application of another powder layer is further reduced. In addition, hard material particles 42 may be surrounded by a special material, which is different from powdery material 41. Due to the special material, hard material particles 42 may be protected against damage by chemical reactions with powdery material 41 in a subsequent compression process, for example with the aid of hot pressing and/or sintering. Cobalt powder or bronze powder, for example, are suitable as the special materials for hard material particles in the form of diamond particles.
[0047] In the illustrated first variant of the method according to the present invention for production of the first green body 10, hard material particles 42 are surrounded by a special material 48. The loose powder particles of powdery material 41 are initially removed from first cavities 26 (
[0048] After first cavities 26 are completely filled with special material 48, the layer construction of first green body 10 continues. Building plane 43 is lowered by fourth layer thickness d.sub.4 in adjusting direction 45, and a fourth powder layer 49 of powdery material 41 is applied with the aid of the powder feed unit (
[0049] The insert height of second cavities 27 is reached after the application of the fourth powder and adhesive layers, and hard material particles 42 may be situated in second cavities 27. The insert height of second cavities 27 is referred to below as second insert height h.sub.2, second insert height h.sub.2 being greater than maximum diameter D.sub.max of hard material particles 42. To protect hard material particles 42 situated in second cavities 27 against damage by chemical reactions with powdery material 41, hard material particles 42 of second cavities 27 are embedded into special material 48, like hard material particles 42 of first cavities 26. The filling of second cavities 27 with hard material particles 42 and special material 48 may take place similarly to the two-part filling method of first cavities 26 illustrated in
[0050] To reduce the complexity in the layered production of first green body 10, the two-part filling method of first cavities 26 with special material 48 may be simplified. The alternative provides that hard material particles 42 are placed into the cavities after the extraction of the loose powder particles, and the cavities are filled with special material 48 after hard material particles 42 are placed. The alternative, which is referred to as the one-part filling method, is described on the basis of the example of second cavities 27. During production of green bodies, the one-part or two-part filling method is generally used for special material 48. The one-part filling method is described on the basis of second cavities 27 but may also be used in filling first cavities 26 with special material 48.
[0051] The loose powder particles are extracted in the area of second cavities 27 with the aid of the extraction unit (
[0052] In the exemplary embodiment, first insert height h.sub.1 of first cavities 26 and second insert height h.sub.2 of second cavities 27 coincide. Alternatively, first and second insert heights h.sub.1, h.sub.2 may be different. The use of cavities having different insert heights, into which the same type of cutting elements is placed, is advantageously useful for green bodies which are further processed into processing segments for abrasive processing tools. In abrasive processing tools, cutting elements, which process a substrate or a workpiece, must be exposed on the upper side of the processing segments. For this purpose, the processing segments are usually sharpened until cutting elements are exposed on the upper side. The sharpening of the processing segments may be omitted or at least reduced if the cutting elements are placed in the area of the upper side in cavities whose insert height is less than a minimum diameter of the cutting elements. During the layered construction, another material layer is applied after the placement of the cutting elements into the cavities. The layer thickness of the material layer may be used to determine whether and to what extent the cutting elements protrude on the upper side.
[0053] After second cavities 27 are filled with special material 48, the layer construction of first green body 10 continues. Building plane 43 is lowered by fifth layer thickness d.sub.5 in adjusting direction 45, and a fifth powder layer 52 of powdery material 41 is applied with the aid of the powder feed unit (
[0054] First green body 10 is manufactured in layers from five material areas 17, 18, 21, 23, 25 having same powdery material 41. Alternatively, the material areas of first green body 10 may be manufactured from different powdery materials 41. In green bodies which are further processed to processing segments for abrasive processing tools, for example, a first powdery material may be used for the first material area, and a second powdery material may be used for the other material areas, the properties of the first powdery material being selected with regard to the connection of the processing segments to the base body, and the properties of the second powdery material being selected with regard to the mechanical connection of the cutting elements. If the processing segments and the base body are to be welded, a weldable first powdery material is selected.
[0055] In first green body 10, hard material particles 42 are embedded into special material 48, the filling of first and second cavities 26, 27 taking place in a one-part or two-part filling method. Hard material particles 42 do not have to be embedded into special material 48. Alternatively, hard material particles 42 may be placed into first and second cavities 26, 27 in powdery material 41; the removal of powdery material 41 from cavities 26, 27 and the filling of cavities 26, 27 with special material 48 being omitted in this case. The use of a special material 48 is useful if first green body 10 is subjected to a subsequent processing by hot pressing and/or sintering for compression purposes, and cutting elements 42 become damaged during hot pressing and/or sintering, due to powdery material 41 used. Special material 48 is selected in such a way that it forms a chemical compound with powdery material 41 and mechanically binds cutting elements 42.
[0056]
[0057] Second green body 60 is constructed in layers with the aid of a building plane 64, a powder feed unit and a print head. A first powder layer 65 of powdery material 61 having first layer thickness d.sub.1 is applied with the aid of the powder feed unit (
[0058] First insert height h.sub.1 of first cavities 26 is reached after the application of the third powder and adhesive layers, so that the placement of first cutting elements 62 into first cavities 26 may take place. The loose powder particles of powdery material 61 are extracted in the area of first cavities 26 with the aid of an extraction unit (
[0059]
[0060] After first cutting elements 62 are placed in first cavities 26 (
[0061] The loose powder particles of powdery material 61 are partially extracted in the area of second cavities 27 with the aid of the extraction unit part of the loose powder particles remaining in second cavities 27 (
[0062]
[0063] A first material template 84 (
[0064] First insert height h.sub.1 of first cavities 26 is reached after the application of third material layer 93, so that the placement of cutting elements 82 into first cavities 26 may take place. Third material template 92 is removed, a first insert template 96 (
[0065] Second insert height h.sub.2 of second cavities 27 is reached after the application of fourth material layer 102, so that the placement of cutting elements 82 into second cavities 27 may take place. Fourth material template 101 is removed, a second insert template 105 (
[0066] Cutting elements 82 of third green body 80 may be embedded into a special material, just like cutting elements 42 of first green body 10, the filling of first and second cavities 26, 27 being able to take place in a one-part or two-part filling process. The use of a special material is useful if third green body 80 is subjected to a subsequent processing by hot pressing and/or sintering for compression purposes, and cutting elements 82 become damaged during hot pressing and/or sintering, due to paste-like material 81 used. The special material is selected in such a way that it forms a chemical compound with paste-like material 81 and mechanically binds cutting elements 82.