MXPA97006629A - Body composed of cut that contains particles of diamond and procedure for its manufacture - Google Patents

Abstract

The present invention relates to a composite cutting body (1), for the abrasive processing of hard bases, for example concrete including diamond particles (3), whose grain size is less than the grain size of composite bodies of cutting, which are embedded in a matrix of a bonding material (2), preferably metal. The grain size of the diamond particle is greater than 50 microns and less than 300 microns. Each composite cutting body (1) is agglomerated and sintered in a single donor process from a mixture of diamond particles (3), and the bonding material (2), having a grain size that is approximately 400 microns to approximately 1,200 micr

Description

COMPOSITE BODY OF CUT THAT CONTAINS PARTICLES OF DIAMOND AND PROCEDURE FOR ITS MANUFACTURE DESCRIPTION OF THE INVENTION. The invention relates to composite cutting bodies for the abrasive processing of hard subfloors, containing diamond particles according to the main idea of claim 1. Furthermore, the invention relates to a method for the manufacture of such cut composite bodies , according to the main idea of claim 8. In many applications of the construction technique, it comes into application tools that are equipped with diamond particles to improve the abrasive properties. For the preparation of larger diameter perforations or ruptures, for example, hollow drilling crowns are used, which at their front end are equipped with cutting segments; also wall saws and separating discs for cutting concrete, stone or ceramic, are equipped with cutting segments on their periphery. The cut segments consist of the essential diamond crystals that are embedded in a metal matrix. The grain size for the diamond crystals used in those cutting segments is from about 300 microns to about 600 microns. The diamond crystals are not uniquely arranged in the surface of the cut segment. otherwise they are distributed in a relatively uniform manner in a part of the height of the cutting segment. In the elaboration of the subsoil, the edges of the surface of the matrix material always come into contact with each other. They belong to the diamond crystals with the material to be treated: with a loss of the diamond crystals that are on the surface, the matrix material wears down to it. that new songs that lie more aoajo remain free. In application, the edges may be slowly rounded or the diamond crystals may break or fall off completely from the matrix material, due to the relatively large grain size of the crystals. diamond, is the number of effective cutting edges for the abrasive work of the suosuela relatively ba o. In case of a diamond crystal I decide to have the rounded edges to break or detach, from the material of the matrix, the cutting effectiveness of the The segment is damaged until the missing cut edge is composed of a new diamond crystal. This disadvantageously affects the cutting speed of the cutting segment. By the US patent document No. 4,591,364: it is known to use diamond cutting bodies for the coating of the aria discs, which are agglomerated with diamond particles of a smaller grain size, typically about 70 naeta 115 microns, by means of a bonding material preferably metallic. The mixture of the diamond particles and bonding material are united by smtering in a flat, smothered paste, this paste or flat piece is then broken into small particles and hovered. This fraction sifted with an l? agglomerated grain size of approximately 149 to 250 microns is applied to the coating of the sharpening discs, the breaking of the sintered paste, leads to a relatively large distribution of the grain size of the composite body of agglomerated cut, so that a part The non-negligible amount of the agglomerate is too large or too small for the coating of the sharpening discs. The separated fractions not only do not have different grain sizes, but also because of the process of breaking the smothered paste. It also presents the danger of being mechanically damaged by the breaking process, for this the separated grain fractions are re-emitted to finally be used as a sharpening and polishing agent.

It is the object of the present invention to create composite cutting bodies which have a tight grain size distribution and which also do not differ essentially in their geometrical form, in the production of cutting compounds, the fall must be largely avoided. Cutting compounds should allow for the easy fabrication of cutting elements and cutting segments that have a high cutting capacity. In addition, losses in cutting efficiency caused by the rounding of the protruding edges of the diamond particles by rupture or loss of the diamond particles should be prevented. If this is present, it should be possible to compensate with the greatest possible speed, and also the manufacturing process of the composite cutting bodies should be able to be carried out in a simple and reproducible manner. The mechanical damage of the composite cutting bodies must be eliminated by additional breaking processes and also the sifting processes must be eliminated. The solution to these problems consists of composite cutting particles, which have the characteristics stated in the characteristic part of claim 1, the process according to the invention for its manufacture, includes the procedural steps presented in the characteristic part of the invention. Claim 6. Especially, a composite cutting body is created by the abrasive work of hard bases, especially concrete, which contains diamond particles that are embedded in a matrix of a preferably metallic bonding material. The grain size of the diamond particles applied is less than the grain size of the cut composite bodies, being greater than 50 microns and less than 300 microns. Each compound cutting body is agglomerated in an individual modeling process from a mixture of diamond particles and bonding material which is then sintered and has an approximate grain size of 400 microns to 1,200 microns. When each composite cutting body is manufactured in a single molding process from the mixing of the diamond particles and bonding material, the grain size and the shape of the joint cutting body can be controlled to some extent. The manufacturing process is widely reproducible. The composite cutting bodies produced in this manner have a very compact or narrow grain size distribution and are similar in geometrical form, so that all manufactured composite cutting bodies can be reworked as a rule. The grain size of the composite cutting bodies from about 400 microns to about 1,200 microns corresponds largely to the grain size of the diamond crystals used for further processing in the cutting segments. Therefore, the cutting bodies can be conveniently embedded in the matrix material, when the composite cutting body consists of a multiplicity of small diamond particles bonded together, many edges are available for the abrasive work of the base. , in this way a rounding of individual edges, a break or a loss of a diamond particle does not act in an essential way against the abrasive properties of the composite cutting body. The grain size of the diamond particle is greater than 50 microns and less than 300 microns, so they are used reasonably for the composite bodies of smaller grain size cut, the diamond particles that are finer and for the bodies Cutting compounds larger, larger diamond particles. Diamond particles of smaller grain sizes, not only cheaper than the larger diamond crystals used, but diamond particles of small grain sizes also by general rule, are less prone to damage. In this way, the individual diamond particles have better mechanical properties than diamond crystals of large grain size.

This advantage is also transmitted to the mechanical properties of the composite cutting bodies. The manufacture of the composite cutting bodies is carried out directly without the process of breaking a smelt paste with a subsequent sifting process. The disappearance of the additional processing steps simplifies and lowers the manufacturing process of the composite cutting bodies, in addition to which the danger of mechanical damage to the composite cutting bodies is born. The composite cutting bodies, which are made of bonding material and small diamond particles, have an extraordinarily large strength and good bonding properties, if the bonding material includes a nickel or cobalt oase with the addition of siliceous or ooro, and active elements with a limiting surface, for example chromium. The siliceous and ooro are added because of the collapse of the melting point, chromium is an active element of the limiting surface that ensures a chemical bond between the particle and the particle by means of the formation of a carbide. Especially good hardening properties, together with good bonding properties are achieved without the preferred metal bond alloy having, from 1 to 25% C, from 2 to 0% Si. from v. 5% to 4% B, and 50 to 95% Ni.

The percentages are referenced each time to the weight of the alloy. The missing% by weight are taken from the other constituent parts of the link alloy, for example Fe or Co. When the volume concentration of the diamond particles is from about 20% to about 80%, preferably about 30 to 70%, of the volume of the agglomerate body composed of cutting, a large number of cutting edges is produced. Even when some edges are used round or diamond particles are completely removed from the joint, there will still be enough diamond particles, so that the cutting capacity of the composite cutting bodies hardly suffer any non-essential deterioration. The agglomeration of the mixture of diamond particles and bonding material takes place with the aid of a pasty carrier in the cavities of a mask, it can be an expanded molded body made of synthetic material, for example, rubber-silicon, which mixture after a drying step at moderate temperatures in which the organic binding agent is imputed, is deformed before it is sintered together. Preferably, the agglomeration and sintering is carried out in a rigid mask made of ceramic that is not wetted by the metal bond alloy. In this case, the removal of the mold is particularly simple, and it can be effected in a simple manner by the agitation of the mask, suitable ceramic materials being for example aluminum oxide, zirconium oxide, hexagonal boron nitride. The pre-dried mixture can with the use of ceramic masks for the sintering process, where at least reach the temperature of the solid of the metal bond, remain in the cavities of the mask, you can also use metal masks, in this case, it remains The mask after the agglomeration and sintering is performed as a constructive part of the composite cutting body and ie provides additional strength. The composite cutting bodies can be applied in the usual manner directly to the cutting discs or the like, when, for example, they are embedded in a synthetic ream coating of the surface of the cutting disc. In an advantageous application of the present invention, the composite cutting bodies are prepared for abrasive cutting elements which are hot pressed with one another, directly. The hot pressing process takes place under a pressure of approximately 5-50 MPa, the temperature is approximately 70? to 1,000"C. The special advantage of composite cutting bodies made of particles smaller than the grain size and bonding material, consists of that then you can easily work to voiver the diamond segments. In the following elaboration, the cutting bodies composed of the crystals of diary used now are not differentiated from the same grain size. Cutting bodies composed preferably of a metal matrix material, which is softer than the preferred metal bond material of the composite cutting bodies. Diamond segments constructed in this way have the advantage that they are -sharpening on two sides; Once the diamond segment is used, the softer matrix material is polished and new composite cutting bodies are always present on the surface. On the other hand, it also takes place in the composite cutting body, a self-sharpening when the material of eniace of the composite cutting body wears out in a certain periphery and always new particles of small diamonds arrive at the surface of the compound cutting body. , and they come back with their songs, effective for the cut. The process according to the invention for the manufacture of composite cutting bodies for the abrasive processing of hard bases, for example concrete, in which a mixture of diamond particles of a grain size is agglomerated which is less than the magnitude of The grain of the composite cutting bodies, and preferably a metallic eniace material for a bonding and then sintering, is characterized in that the diamond particles are selected such that their grain size is greater than about 50 microns and less than about 300 microns and because the mixture of the diamond particles and eniace material, each time is modeled and sintered in a process of joining individual moideo to obtain a composite body of cut of a grain size of approximately 400 microns to approximately 1,200 microns . The composite cutting bodies should no longer be broken and then sifted, but already have the desired grain size after the individual bonding and molding process. Practically 100% of the composite cutting bodies produced in this way remain available for further processing; no accident occurs in which the desired grain size is not present. Through the process of donation on an individual basis, the form of the composite body is also controllable, which facilitates its further elaboration. The individual donor process according to the invention, consists in that the mixture of diamond grain and material of eniace, are applied to the donation of form by means of a pasty carrier in individual cavities of fine ceramic masks with synthetic material. The reaction, preferably a Siiicone rubber, by a heat treatment expels the organic fraction of the eniace material and the obtained mixture is purified at a vacuum at a temperature of approximately 900 to 1,300 °. where in the ceramic or metal masks it remains in the cavities for the smterization process or in a ceramic plate or in a bed of corundium, in a smtepzacion, in a lecno of corundium the separation of the lu composite grains is cut of the corundium particles by sifting. In a ceramic mask, the cut composite bodies can simply be shaken to detach them. In a metallic mask this form is inclusive a constituent part of the composite grain cutting and strengthens its structure. A nickel or cobalt-based alloy with addition of siliceous or chorus and active elements in the limiting surface, for example chromium, is selectively used as the metallic eniace material. The composition of 2u alloy eniace is 1% - 25% Cr, 2% - 6% oi, 0.5 - 4% B and 50% - 95% Ni. The percentages refer to the total weight of the alloy; the missing%, if any, are taken from other constituents of eniace alloy, for example, Fe or Co. With this, the concentration The volume of the particles per day is chosen at about 20 to 30%, preferably about 30 to 70%, of the volume of the agglomerated cutting composite. With the selected composition and the high fraction in particles per day, cutting composite bodies can be made. which exhibit the good cutting properties desired with sufficiently high mechanical strength. Next, the invention will be clarified with reference to the schematic representations that are not made on a scale. Where it shows: FIGURE 1, a view of a cut composite grain; FIGURE 2, a view of an effective front surface for the cutting of a diamond segment; FIGURE 3, a representation to be mtuible of the cutting process with a conventional cutting segment; ? FIGURE 4, a representation to be intuitive of the cutting process with a diamond segment according to the invention with composite cutting bodies. A cutting body composed in accordance with the invention is shown in FIG. 1, being indicated by the figure 1. This covers a multiplicity of particles of dia. 3. which are embedded in a metal preferably metallic material 2, the particles of diamond 3, have a grain size greater than 50 microns and less than 300 microns and agglomerate and sinterize an individual molding process in composite bodies of cut, with a grain size of approximately 400 microns, 200 microns. The diamond particles 3. embedded in the metal preferably metallic material 2, in the vicinity of the surface, protrude with their edges 4, from the surface of the composite cutting body 1. The metal preferably metallic material, comprises an alloy of base of nickel or cobalt with addition of siliceous or boron, and active elements on the surface limit, for example, chromium, siliceous and boron that are added with the aim of lowering the melting point for the sintering process, the chromium is a active element in the limit surface that ensures a fixed chemical eniace of the diamond particle through the formation of a carbide. The preferably metallic alloy material preferably consists of an alloy of 1% -25% Cr, 2% -6 / Si, 0.5% -4% B and 50% -95% Ni. Percent percent refer each time to the alloy weight set. The percentage that is missing, if any, is taken from the other constituent parts of the link alloy, for example Fe or Co. The average grain size of the eniace material is about 5 microns to about 100 microns, preferably less than 20 microns.

The eniace material is brought before mixing with the diamond particles in a granular structure process step, to a grain size which is comparable with the magnitude of the diamond particle. This improves the uniform mixing of the individual constituent parts of the cut composite body 1; for the manufacture of the composite cutting body 1, the mixture of the diamond particles 3 and the eniace material 2 is put, by means of a pasty carrier, for example wax, alcohols with rheological components that will prevent a de-mixing, in the cavities of a mask, the mask may have a rigid formation, for example, be ceramic or metallic. It may also consist of an expandable movable body made of a synthetic material, for example, siiicone rubber. After a drying step in which at moderate temperatures of about 50 to 70 *, the organic part of the binder is expelled, there is a vacuum sintering process in which at least the solidification temperature of binder 2 is reached, preferably metallic. The sintering temperatures used are typically between 900 to 1,300"; If the drying step is performed in a ceramic or metal mask, the dry mix can remain in the mask for the vacuum sintering process. In a suitable selection of the material for a metal ID mask, the composite cut-off body is already sintered or not deformed once afterwards, but the mask can remain as a constituent part of the cut composite body 1. apart from the advantage of the disappearance of the removal step from the moide, the metallic mask represents a donor characteristic of additional structure to the composite cutting body. If mixing and drying is carried out in a flexible mask made of synthetic material, for example silicone rubber, the pre-dried mixture is removed from the mois before the vacuum sintering process. Due to the great expandability of the synthetic mold, the ease of removal is guaranteed, the stability of the pre-mix is sufficiently high to ensure safe subsequent handling. For the sintering process, the mixture is placed in a ceramic plate, for example, of aluminum oxide or in a piece of carbide, after being subjected to the vacuum cleaning, the composite bodies of section 1 can be separated by sifting from the curved grains. The donor processes individually, have the advantage that it is adjustable and widely controllable in the size and shape of the composite bodies of cut 1. The bodies produced cutting compounds i, present with this, as a whole or totality the shape and size of the bodies. desired grain. They can be used directly as abrasive cutting bodies, for example. cuanoo are directly embedded in a synthetic resin coating of a sharpening disc. The composite cutting bodies 1, according to the invention, can also be used by joining them to larger abrasive cutting elements. For this, the composite cutting bodies 1 are joined, for example, by a hot pressing method. Here pressures of about 5 NPa up to 50 MPa are presented. The process temperatures are approximately between 700 and 1,000 °. Here the preferably metallic material of the individual cutting composite bodies 1 melts and generates an amorphous cutting element of the desired shape, from whose surface the edges 4 of the diamond particles 3 protrude close to the surface. The amorphous cutting elements can be manufactured, assuming the ability to remove the moide in any way they want. In a particularly advantageous application of the composite cutting bodies 1, these are further processed in the usual manner as diamond crystals of a larger grain size to form diamond segments for drill bits, separation discs, saws and the like. A section of the diamond segment is shown in FIG. 2, and is denoted as a whole by the figure 10. The diamond segment 10 comprises a number of cut composite bodies 1, which are embedded in a material of metallic matrix 5. The metallic matrix material 5 is softer than the metal metallic material 2 of the composite cutting body 1. An example for a suitable matrix material 5 is described in US Pat. No. 5,186,724 corresponding to the European patent. 481917, the content of which is declared as an integral part of the present patent application. The concentration of the composite cutting bodies 1, corresponds largely to the concentration of the diamond crystals of a larger grain size in the conventional segments of the diamond cuts, presents approximately 5 to 40% in reference to the volume of the segment of diamond cut 10, the diamond particle 3, close to the surface of the composite cutting body 1, protrudes from the surface 0, of the diamond cutting segment 10, and forms with the others a uitipicity of effective cutting edges, whose Cutting traces are indicated in the segment in Fig. 2, by lines L. The direction of manufacture is indicated by the arrow =. Figs. 3 and 4, serve to intuitively make the cutting process with a conventional cutting segment (Fig. 3) and with a cutting segment 10, with composite cutting bodies 1, according to the invention tFig. 4). The S fly gives every time the direction of elaboration. Fig. 3 shows an E edge, of a diamond crystal, which in abrasive processing enters attack with the base ß, and removes the material? . By contrast, the composite body of cut 1 has the same size, a multiplicity of edges 4, which protrude from the surface of the eniace material 2, and belong to the small particles of diamond 3, close to the surface. Not only an edge E. of a crystal of day D, it enters into a grip with the base B, iFig. 5 > , but this is worked by a multiplicity of edges 4, all of which remove the removed material A. If in the cutting segment according to FIG. 3, the working edge E, it will be cut or the diamond crystal If the diamond segment falls off this cut for all abrasive processing, then as long as there is enough matrix material in the diamond cutting segment, it will exit or protrude a new diamond crystal D from the surface cutting day. In the cutting segment according to the invention, a series of edges 4 of the composite cutting body 1 are produced, which are applied on the base B. In case a edge 4, remains blunt or a particle of diametre 3 , disappear by rupture, this would have a non-essential effect, since there are -_0 enough songs 4, available. In principle, too, a large amount of matrix material of the diamond cut segment must not be detached until the ineffective or lost edge 4 is replaced, a very low amount of the bonding material of the composite cut-off body 1 must be worn out, that the new particle of diamond 3, is free whose edges 4, detach material A. This effect of self sharpening is much better than the usual sharpening effect, because now the new composite body of cut 1, is free in the material of matrix of the diamond cutting segment, with this, the diamond cutting segment according to the invention, is doubly self sharpening.

Claims (9)

1. CLAIMS 1.- Compound cutting bodies for the abrasive processing of hard bases for example concrete including diamond particles whose grain size is less than the magnitude of the grain of the composite cutting body, which are embedded in a matrix of bonding material preferably metallic, characterized in that each composite cutting body is agglomerated and sintered in an individual form-giving process from a mixture of diamond particles of a grain size greater than 50 microns and less than 300 microns and of the binding material, and the size The grain of the cut composite body is approximately 400 to 1, 200 microns.
2. 2. Compound cutting bodies according to claim 1, characterized in that the eniace material has an alloy based on nickel or cobalt with addition of siliceous or boron in addition to active elements in the boundary surface, such as for example chromium.
3. 3. Compound cutting bodies according to claim 2, characterized in that the link alloy has 1% -25% Cr, 2% -o% Si,? 5% -4% B, and 50% -95% Neither, where the% refer each time to the total weight of the alloy and the percentage that is missing, if any, is given of other constituent parts of the link alloy, for example Fe or Co.
4. -i.- Composite bodies ce ence in accordance with one of the preceding claims. characterized in that the volume concentration of the dialyzed particles is from about 20 to 80% preferably about 30 to about 70% of the volume or the agglomerated cutting composite.
5. 5. Cutting composite body according to one of the preceding claims, characterized in that the agglomeration of the mixture of the particles of dialysate with the eniace material is carried out in a ceramic mask made, for example, of aluminum oxide, zirconium oxide or hexagonal boron nitride.
6. 6. Abrasive cutting element characterized by a multiplicity of cutting composite bodies according to one of claims 1-5, which are pressed one with the other at elevated temperature.
7. 7. Segment diamond cut characterized by a multiplicity of cut composite bodies according to one of claims 1-5, which are embedded in a preferably metallic matrix material, which is softer than the material of eniace preferably metallic of the composite cutting body.
8. 8. Process for the manufacture of composite cutting bodies for the abrasive processing of hard bases, for example concrete in which a mixture of diamond particles whose grain size is less than the grain size of the composite bodies is cut. The mixture containing preferably metallic material, is agglomerated and then sintered, characterized in that the grain size of the diamond particles is greater than 50 microns, and less than 300 microns, and the mixture of the diamond particles and The binding material is molded and sintered in an individual form donation process to a composite cutting body having a grain size of approximately 400 micras nasta 1,200 microns.
9. 9. Method according to claim 8, characterized in that the mixture of diamond grains and eniace material for shaping is put by means of a pasty carrier in individual cavities of masks made, either of flexible synthetic material preferably rubber Siiicone, ceramic, preferably aluminum oxide, sirconium oxide, hexagonal boron nitride or metal by means of a heat treatment is expelled the organic fraction of the eniace material and the previously treated mixture is exposed to a vacuum at an approximate temperature of 900 to 1300 °, remaining in the masks made of ceramic or metal in the cavities or is given to a ceramic or carbide bed.

   10. - Process. according to claims 8. 9. characterized in that a nickel or cobalt-based alloy with addition of chromium, siliceous or boron is selected as the metallic bond material, the composition of which comprises l% -25% Cr, 2% -6% Yes, 0.5% -4% B, 50% -95%

   Neither, where the%, each time refer to the total weight of the alloy, and the%, which are missing, if any, are taken from other constituent parts of the alloy eniace, for example Fr or Co, and the volume concentration of the diamond particles are selected at about

   20 to 80%, preferably 30 to 70% of the volume of composite body of agglomerated cut.

   R E S U E A composite cutting body is presented. { ! ), for the abrasive processing of hard bases, for example concrete including diamond particles (3), whose grain size is less than the grain size of the composite cutting bodies, which are embedded in a matrix of a material of The metal particle size of the particle is greater than 50 microns and less than 300 microns, each compound composite of cut i 1 j, is agitated and sintered in an individual donor process from a mixture of diamond particles l3), and the eniace material (.2), having a grain size that is about 400 microns to about 1,200 microns.