CN101048259B - Grinding material and its preparation method - Google Patents

Abstract

The invention relates to an abrasive product wherein abrasive grains are embedded in a matrix which comprises a cell-free, duroplastic binding agent for the abrasive grains, and wherein a contact surface which is provided with abrasive grains and which is used to abrade a workpiece is embodied. According to the invention, the matrix is elastically flexible such that the abrasive grains which cover the contact surfaces are pressed into the matrix during the abrasive step. The abrasive grains are distributed in the matrix in such a manner that an additional contact surface covering the abrasive grains is released when the matrix in used in the diagonal direction for the original contact surface provided with abrasive grains. The abrasive grains are distributed in the matrix in such a manner that they are diagonal and also parallel on the respective contact surface of the abrasive counter to the reverse force of the matrix. Said matrix is joined in a flexible manner to the base, and is bound directly via the binding agent contained in the matrix.

Description

A kind of abrasive material and preparation method thereof

technical field

Generally, the present invention relates to an abrasive material in which abrasive particles are embedded in a binder matrix and in which a contact surface covered by the abrasive particles is provided for abrading a workpiece.

Background technique

Since the development of such abrasives, it has been known to produce abrasive composites of homogeneous structure. For this purpose, initially non-elastic binders were used, whereas elastically compliant binders have been used for decades. An example of an abrasive composite using a non-elastomeric binder is a grindstone. An example of an abrasive composite using an elastically compliant binder is a compact composite, eg in the form of cubes or other abrasive compacts formed into a grinding wheel. Both porous and non-porous embodiments are known in this regard. These known abrasive blocks were and still are whole castings practiced by the applicant's 40+ year proven track record of success.

Heretofore, these known abrasives using elastically compliant binders for the abrasive grains have been routinely produced without the need to incorporate substances in the abrasive due to their construction as abrasive blocks. In contrast, for abrasives with non-elastomeric binders, the term "backed abrasives" in this section has been in a category of its own for decades.

The invention also particularly relates to abrasive materials having a non-porous, especially non-foamed binder as opposed to a porous, especially foamed binder.

Referring to the German Plastics Handbook "Saechtling Kunststoff Taschenbuch, 28 ^th Edition, by Karl Oberbach, published by Verlag Hansa, see page 555, Fig. 4.18", it is clear that no matter where PUR (polyurethane) is involved, or about all other foams Adhesives that typically make the difference between foam and non-porous adhesives.

In this context, the particularly basic non-porous PUR type of the invention belongs to the group:

solid polyurethane

cast and sprayed elastomers

thermoplastic elastomer

rubber

The elastically compliant blocks originally cited in the prior art and the "solid" composites in the cited groupings respectively are special cast elastomers, which are also used in the abrasives of the present invention.

When the adhesive is made into a foam adhesive, a distinction is made between a material that is foamed physically and mechanically by the application of air, and a material that is chemically foamed by the use of a blowing agent.

Abrasives with non-porous binders according to the invention are characterized in that neither physical nor chemical targeted foaming takes place by means of corresponding curing operations. The replacement is aimed at avoiding swelling as much as possible, although in practice the formation of residual porosity can never be completely avoided. This is why, at least in describing abrasive products specifically designed and manufactured for the market, it is best to refer to real and theoretical densities compared to practice.

This comparison is best illustrated by taking PUR as an example for foaming adhesives. When reading the cited German Handbook of Plastics "Saechtling Kunststoff Taschenbuch, 28 ^th Edition, by Karl Oberbach, published by Verlag Hansa, see pages 554 et seq.", shaped foam (30-300kg/m ³ ), rigid foam (30- 90 kg/m ³ ) and open cell foams (20-40 kg/m ³ ).

According to the invention, PUR is used, in particular with a density of not less than 800 kg/m ³ which adequately describes the minimum porosity.

Backed adhesives in which the abrasive composite material exhibits the characteristics of porous, in particular foamed, adhesives are disclosed, for example, in German patents DE 3114001 A1 and DE 1907983 A1.

In summary, the present invention relates particularly to abrasives, composites comprising abrasive grains in a thermosetting binder. Here, the invention relies on thermosetting plastics known as binders for composite abrasive grains, such as polyurethane, although rubber can also be used in the present invention as binders for abrasive grains.

An example of a thermoplastic binder for abrasive grains in the form of plasticized collodoxyline in German patent DD 106585A, different from the thermosetting plastics used within the scope of the present invention, also needs to be in roughly equal proportions 1: 1 or 0.8:1 use plasticizer. It is also necessary to control the loading ratio of the abrasive to at least 60% by weight of the abrasive powder in the abrasive composite, a proportion of more than 80% relative to the abrasive powder is incidentally considered detrimental to bonded abrasive composites. It is particularly recommended to arrange such known abrasive composites as abrasive composites in which the thickness of the very thin layer of abrasive when measured perpendicular to the backing is 10 μm to a maximum of 40 μm.

It is for the sake of completeness that reference is also made to more extrinsic known abrasives, whereby kneadable binders for abrasive grains are determined to be suitable for the workpiece surface profile for grinding (German patent DD255903A1).

In the process of technological development as abrasives currently include processing speeds, such as rotary or oscillating operations on the sides of grinding tools or grinding machines, have always become faster, and the homogeneous abrasives with elastic and compliant binders produced over decades have become The inability to resist the resulting acceleration and traction forces, including centrifugal forces, without special measurement, results in premature failure of the abrasive matrix formed by the elastically compliant binder. One of these particular measurements used with grinding wheels involves dimensioning the abrasive coating of the solid core of the wheel, making the abrasive thinner and thinner, yielding a relatively short shelf life. For endless abrasive belts, it was considered almost half a century ago to coat the endless belt as a backing with strip-shaped abrasive composites, in each case forming a matrix containing abrasive grains by soft foaming of polyurethane, whereby these The abrasive grains are secured to the endless belt in a discrete bonded manner (see British Patent GB B 821929, especially page 2, lines 3 to 7). However, the point of this invention necessitates an unreasonably complicated process in serial production due to the necessity of blocking the abrasive composite material and the associated detached bonding, which is why it cannot be accepted in practice.

For conventional abrasive grinding, the abrasive grains are usually always bonded directly to the backing by means of non-elastic adhesives such as initially hide glue and now synthetic resins, said abrasive grains being sized as a result of the need Selected. This backing absorbs the traction and centrifugal forces generated in the machine. In this conventional case, the abrasive grains are attached to the backing only in a separate layer and protrude from the surface of the abrasive in contact with the workpiece through abrasive protrusions. When these protruding portions are worn out during grinding, the adhesive immediately comes into frictional contact with the workpiece, the efficiency of grinding is remarkably reduced, and the adhesive loaded on the worn surface of the workpiece is damaged.

For abrasives in which the abrasive grains are uniformly arranged in a radiation-cured non-elastomeric binder matrix on a backing bonded by an adhesive, the matrix is divided into a plurality of discrete matrix bodies with interstices that are free from the workpiece. The orientation of the contact surface acts on the backing to increase the cross-section parallel to the backing (German patent T2 69210221).

In other words, the smaller size of the abrasive grains in the erosive grinding abrasive portion of the abrasive grains protruding from the contact surface results in an overall better polishing of the wearing surface. In this regard, there is a need to discern a polishing comparable to honing or lapping that substantially no longer includes corrosive grinding, while reducing the peak-to-valley height of the surface.

For use in modern grinding machines, abrasive nonwovens are now usually provided as polishing abrasives. From German patent DE-T2 69609709 (particularly claim 4) it can be seen that a plurality of abrasive grains are bonded to an open loose fabric of organic fibers via a binder system. The polishing associated therewith produces scarring on the machined surface that bends or breaks. Defects on the polished surface of the workpiece, such as scratches and scratches, are merely masked, not actually removed.

Contents of the invention

1. An abrasive, wherein abrasive grains (8) are uniformly dispersed in a matrix (4) containing a non-foaming and non-porous thermosetting binder for said abrasive grains (8) (6), and wherein the contact surface (10) covered by abrasive grains (8) is designed for grinding a workpiece;

It is characterized by a combination of the following characteristics:

(a) the degree of elasticity and compliance of the matrix (4) makes the abrasive grains (8) covering the contact surface (10) pressed into the matrix (4) during grinding;

(b) said abrasive particles (8) are dispersed in the matrix (4) such that consumption of the matrix (4) perpendicular to the contact surface (10) initially covered by the abrasive particles (8) releases the Covered deeper contact surfaces (10);

(c) said abrasive particles (8) are dispersed in the matrix (4) such that they obey the resiliency of the matrix (4) perpendicular and parallel to the corresponding contact surface (10) of the abrasive;

(d) the substrate (4) is bonded to the flexible backing (2);

(e) The substrate (4) is directly bonded to its flexible backing (2) by means of an adhesive (6) contained within the substrate (4).

2. Abrasive according to item 1, characterized in that the density of the binder (6) in the matrix (4) is not lower than 90% of the specific gravity of the binder (6) substance.

3. The abrasive according to item 1, characterized in that the elasticity of the matrix (4) is not less than 35%.

4. The abrasive according to item 3, characterized in that the elasticity of the matrix (4) is not less than 40%.

5. The abrasive according to item 1, characterized in that the elasticity of the matrix (4) is not greater than 55%.

6. The abrasive according to item 5, characterized in that the elasticity of the matrix (4) is not greater than 50%.

7. The abrasive according to item 1, characterized in that the hardness of the matrix (4) is not lower than 40 Shore A.

8. The abrasive according to item 7, characterized in that the hardness of the matrix (4) is not lower than 45 Shore A.

9. The abrasive according to item 1, characterized in that the hardness of the matrix (4) is not higher than 75 Shore A.

10. The abrasive according to item 9, characterized in that the hardness of the matrix (4) is not higher than 70 Shore A.

11. The abrasive according to item 1, characterized in that the ultimate elongation of the matrix (4) is not lower than 150%.

12. The abrasive according to item 11, characterized in that the ultimate elongation of the matrix (4) is not lower than 170%.

13. The abrasive material according to item 1, characterized in that the flexural rigidity of the backing (2) detected by a detection width of 15 mm, a detection distance of 20 mm and a rotation angle of 15° is not higher than 5000 mm ox.

14. The abrasive according to item 1, characterized in that the thickness of the matrix perpendicular to the backing (2) is not less than 200 μm.

15. The abrasive according to item 14, characterized in that the thickness of the matrix perpendicular to the backing (2) is not less than 500 μm.

16. The abrasive according to item 15, characterized in that the thickness of the matrix perpendicular to the backing (2) is not less than 1000 μm.

17. Abrasive according to item 1, characterized in that the thickness of the matrix perpendicular to the backing (2) is not higher than 2500 μm.

18. Abrasive material according to item 17, characterized in that the thickness of the matrix perpendicular to the backing (2) is not higher than 1500 μm.

19. Abrasive material according to item 1, characterized in that in the ratio of the volume percentage of the abrasive grains (8) to the volume percentage of the binder (6) of the matrix (4), the abrasive grains ( 8) The volume percentage is less than or equal to 80 volume%.

20. Abrasive material according to item 19, characterized in that in the ratio of the volume percentage of the abrasive grains (8) to the volume percentage of the binder (6) of the matrix (4), the abrasive grains ( 8) The volume percentage is less than or equal to 60 volume%.

21. Abrasive according to item 1, characterized in that in the ratio of the volume percentage of the abrasive grains (8) to the volume percentage of the binder (6) of the matrix (4), the abrasive grains ( 8) The volume percentage is greater than or equal to 20 volume%.

22. Abrasive material according to item 21, characterized in that in the ratio of the volume percentage of the abrasive grains (8) to the volume percentage of the binder (6) of the matrix (4), the abrasive grains ( 8) The volume percentage is greater than or equal to 40 volume%.

23. The abrasive according to item 1, characterized in that the size of the abrasive particles (8) is 2-2000 μm.

24. The abrasive according to item 23, characterized in that the size of the abrasive particles (8) is 70-540 μm.

25. Abrasive according to item 24, characterized in that the abrasive grains (8) have dimensions P36, P60, P120 and P240 according to FEPA standards.

26. The abrasive according to item 1, characterized in that, the Shore hardness of the abrasive in the Shore hardness A range is 60°-90° Shore A.

27. Abrasive material according to item 1, characterized in that the binder (6) contains polyurethane.

28. Abrasive material according to item 27, characterized in that said binder (6) is made of one of said polyurethanes.

29. Abrasive material according to item 1, characterized in that the binder (6) contains rubber.

30. Abrasive material according to item 29, characterized in that said binder (6) is made of one of said rubbers.

31. Abrasive material according to item 1, characterized in that the binder (6) contains polysulfide.

32. Abrasive material according to item 31, characterized in that said binder (6) is made of one of said polysulfides.

33. Abrasive according to item 1, characterized in that the binder (6) contains acrylate.

34. Abrasive material according to item 33, characterized in that said binder (6) is made of one of said acrylates.

35. Abrasive material according to item 1, characterized in that the binder (6) is filled.

36. Abrasive according to item 1, characterized in that, in addition to the binder (6), the matrix (4) also contains at least one filler and/or at least one dye and/or at least one additive.

37. Abrasive material according to item 35 or 36, characterized in that kaolin is provided as filler.

38. Abrasive material according to item 35 or 36, characterized in that at least one foam suppressor is provided as an additive.

39. Abrasive according to any one of items 1, 35 and 36, characterized in that the abrasive particles (8) contain at least one silicon carbide and/or at least one silicon dioxide.

40. Abrasive material according to item 39, characterized in that the abrasive grains (8) consist of at least one silicon carbide and/or at least one silicon dioxide.

41. The abrasive according to any one of items 1, 35 and 36, characterized in that the abrasive particles (8) are made of at least one alumina and/or at least one alumina mixed crystal composition.

42. Abrasive material according to any one of items 1, 35 and 36, characterized in that at least a part of said abrasive particles (8) consists of at least one hard metal.

43. The abrasive material according to any one of items 1, 35 and 36, characterized in that the abrasive particles (8) disposed closest to the backing (2) rest on the backing lining (2).

44. Abrasive material according to any one of items 1, 35 and 36, characterized in that said matrix (4) including its abrasive grains (8) is divided and dispersed on the same backing (2 ) and spaced from each other several matrix bodies (4a) having a uniform cross-section in a direction perpendicular to the initial contact surface (10) or backing (2).

45. Abrasive material according to item 44, characterized in that the matrix bodies (4a) have a polygonal cross-section parallel to the backing (2) and are staggered with each other in the grinding direction (16).

46. The abrasive according to item 45, characterized in that the polygonal cross-section is hexagonal, and two corners in the grinding direction (16) or opposite to the grinding direction (16) are used The two corner orientations in the direction.

47. Abrasive according to item 44, characterized in that the matrix bodies (4a) have a circular cross-section parallel to the backing (2) and are staggered with each other in the grinding direction (16).

48. Abrasive according to any one of items 1, 35 and 36, characterized in that the backing (2) consists of woven fabrics, knitted fabrics, films and/or filament layers .

49. Abrasive material according to item 48, characterized in that the backing (2) consists of natural fibers or artificial fibers, or mixtures thereof.

50. The abrasive according to any one of items 1, 35 and 36, characterized in that the backing (2) is inherently elastic and compliant.

51. Abrasive according to any one of items 1, 35 and 36, characterized in that the backing (2) has a quality finish.

52. The abrasive according to any one of items 1, 35 and 36, wherein the abrasive structure is an endless belt.

53. The abrasive according to any one of items 1, 35 and 36, wherein the abrasive structure is a flat material.

54. The abrasive material according to item 53, wherein said abrasive structure is a bar for an oscillating drive.

55. Abrasive material according to any one of items 1, 35 and 36, characterized in that the abrasive structure is a disc or bow for an oscillating drive.

56. Abrasive according to any one of items 1, 35 and 36, characterized in that the abrasive structure is a disc for a rotary drive, a segmented grinding disc, laminated grinding points or wheel.

57. A process for the manufacture of abrasives according to any one of items 1-56, characterized in that the abrasive grains (8) are first mixed into a matrix with a still low viscosity binder (6) ( 4), the mixture is then applied to the backing (2).

58. A process for the manufacture of abrasive materials according to any one of items 1-56, characterized in that the adhesive (6), while still low in viscosity, is first applied to the matrix ( 4) and then applied to the abrasive grains (8) so that the abrasive grains (8) sink into the backing (2) while the binder (6) is still of low viscosity.

59. The method for producing abrasives according to item 58, characterized in that the abrasive grains (8) are dispersed in the matrix (4), while the binder (6) is still of low viscosity.

60. The method of manufacturing abrasives according to item 58, characterized in that the abrasive grains (8) are applied in several ways to the matrix (4) previously applied to the backing (2), while adhering Mixture (6) is still low viscosity.

61. The method of manufacturing abrasives according to item 57, characterized in that the matrix (4) containing the binder (6) and the abrasive grains (8) are applied to the backing together in a multi-layer coating method (2) up.

62. The method for producing abrasives according to any one of items 58-60, characterized in that the matrix (4) containing the binder (6) and the abrasive grains (8) are coated in multiple layers Applied to the backing (2) by the coating method.

63. The method for producing abrasives according to any one of items 57-61, characterized in that matrix bodies (4a) arranged at intervals are provided on the backing (2) by using masking technique.

64. A method of manufacturing an abrasive material according to any one of items 44-47, characterized in that matrix bodies (4a) arranged at intervals are provided on the backing (2) using masking techniques.

The present invention is based on the object of providing an abrasive of the kind described by the preamble to item 1, which is suitable as an article for preparation in reasonable quantities, as a polishing tool on modern grinding machines, combining a long service life with High consistency in polish quality combined.

This object is achieved by an abrasive having the characteristics of item 1.

In the abrasive according to the invention, when a new contact surface covered by abrasive grains is provided, as in the final stage of the preparation process the covering skin must be exposed by releasing the matrix binder, resulting in protruding from the Part of the abrasive grains on the initial first contact surface of a workpiece. When polishing is effected, these projections of abrasive grains are fully or nearly fully pressed into the matrix, thus substantially eliminating the erosive abrasive effect on the workpiece. avoids or at least minimizes the loading of the wear surface of the workpiece, since when the abrasive grains covering the matrix are lost, the previously surrounding adhesive does not make loading contact with the wear surface of the workpiece, but wears like a rubber . In this setup, the abrasive grains are not lost like this, but fall off little by little from the current contact surface. This abrasive particle loss is continuously regenerated from the depths of the substrate, so that the quality of the polish remains consistent during polishing despite the consumption of the substrate. In fact, this even involves the total consumption of the matrix attached to the backing. In this setup, the backing ensures a consistent processing quality regardless of the degree to which the substrate is consumed, even at high processing parameters such as rotation speed, bending speed or vibration level, while only a few processing steps are possible Rational and cost-effective manufacture of abrasives of the present invention.

It is also particularly emphasized that the combination of the abrasives according to the invention with modern polishing machines enables improvements over hitherto possible. Thus, compared to abrasive nonwovens, the products of the invention achievable with abrasive nonwovens are associated with a minimal erosive effect of further added abrasive particles, whereby according to the invention, defects in the abrasive surface can now not only be hidden, And it can be eliminated or at least corrected. Now, surprisingly, no further polishing is required and subsequent chrome workpieces can be adapted for this.

Wear is essentially determined by the choice of binder, any fillers that may be used, and the type of abrasive grain. The adhesive can be adapted for processing various materials such as brass, aluminum or stainless steel. The abrasives of the present invention are particularly effective in polishing relatively rough workpiece surfaces. Even when the abrasive grains in the abrasives of the present invention are relatively coarse, these surfaces can now be polished to a very fine surface without defects.

After decades of neglect, all this is achieved by going against today's development trends with the aid of an elastically compliant adhesive in the matrix.

Items 2-56 relate to advantageous further embodiments of the abrasive material according to the invention, and items 57-64 relate to preferred plants for producing the abrasive material according to the invention.

As regards the general terminology used, in sub-claims reference is made to the terminology in the sections generally supported by physical data and techniques generally as scope of normalization.

It is particularly outstanding that, by means of the abrasive according to the invention, abrasive composites whose elastically compliant matrix contains a non-porous thermosetting binder are now applied to a flexible shaped backing to directly form an integral composite, i.e. without the need for a separate Facilitation of the bonding layer, whereby on depletion of the abrasive, continuously depleted particles are replaced from the depths of the matrix, and this application continues until all or near total depletion of the abrasive composite to the flexible backing without loss of abrasive quality . In this arrangement, the elastically compliant structure in the abrasive composite comprising the matrix and abrasive grains, together with the flexibility of the backing, imparts an inherent flexibility to the complete abrasive which can be tailored to the particular application. In addition, the same abrasive is now available to the consumer, regardless of the need to be flexible or non-abrasive on the consumer's side, so in many applications it is no longer necessary to provide abrasives with different requirements for the flexibility of the abrasive. Many different abrasives are stocked for various applications.

Item 2 relates to preferred upper and lower limits for binder density in the matrix and in the abrasive composite, respectively.

Items 3-12 relate to preferred selection criteria considering the elastically compliant structure of the matrix with reference to elasticity (items 3-6), hardness (items 7-10) and ultimate elongation (items 11 and 12).

Limits quoted in items 2-12 for ranges of density (item 2), elasticity (items 3-6), hardness (items 7-10) and ultimate elongation (items 11 and 12) The values are determined standardizedly, in particular according to the standards of the German DIN (German Organization for Standardization) or the worldwide valid ISO (International Organization for Standardization) standards, each referring to the following standards:

Density: DIN 53479 and ISO 1183 respectively (item 2)

Elasticity: DIN 53513 and ISO 527-2 respectively (items 3-6)

Hardness: DIN 53505 and ISO 868 respectively (items 7-10)

Ultimate elongation: DIN 53504 and ISO 527-1 (items 11 and 12), respectively.

Item 13 relates to preferred criteria when the substrate or abrasive composite backing is required to be flexible.

Items 14-18 relate to preferred ranges for the required minimum thickness (items 14-16) and maximum thickness (items 17 and 18) of the substrate perpendicular to the backing. Currently, preferred thicknesses for applications are 1000 μm or 1.0 mm and 1500 μm or 1.5 mm. In this sense, a particularly outstanding application of the invention is the production of abrasives as flat materials, especially web-like materials.

Items 19-22 relate to preferred ranges of volume percent ratios of abrasive particles of the matrix to binder, requiring lower limits (items 19 and 20) and upper limits (items 21 and 22).

Items 23-25 state preferred particle size ranges for the abrasive particles.

Item 26 states the preferred range of Shore hardness of the abrasive.

Items 27-34 relate to preferred materials for non-porous thermoset adhesives, item 35 adhesives can typically be filled in branches, while items 36 and 37 state specific formulations.

Item 38 relates to specific formulations for avoiding as far as possible the foamability of the adhesive within the scope of the present invention. For this purpose, item 38 states the use in particular of foam suppressors as additives to binders.

Items 39-42 relate to selection of preferred types of abrasive grains.

Item 43 relates to the preferred arrangement of abrasive grains in the matrix.

Items 44-47 relate to preferred sub-divisionings of the matrix into individual matrix bodies.

Items 48-51 relate to preferred backing structures.

Items 52-56 relate to preferred geometries of abrasives for various abrasive tools.

Of particular importance is the variant stated under item 52, in which the abrasive according to the invention is formed as an endless belt. In this structure, its action on the workpiece for the same abrasive can also vary depending on the position of the endless belt, resulting in an action on the workpiece. For this effect, the position is particularly preferably on the one hand on the contact wheel and on the other hand on the free side of the endless belt, whereby the hardness of the contact wheel and the belt speed can be influencing factors.

The present invention also relates to the production method of the abrasive of the present invention according to items 57-64.

A known method is seen in US Patent No. 5,562,745.

The invention will now be described in detail by way of specific example embodiments with reference to FIGS. 1-3 which generally illustrate the gist of the invention.

Description of drawings

Figure 1 shows a partial view of the abrasive contact surface;

Figure 2 is a partial view on an enlarged scale relative to the white circle in Figure 1;

Figure 3 illustrates a cross-sectional view on a larger scale of the portion of the same abrasive perpendicular to the contact surface.

Detailed ways

In all of the abrasives shown in the figures, a flexible support backing 2 is bonded to a matrix 4 (shown dotted in FIG. Foamed polyurethane as well as fillers and additives, whereby the abrasive grains 8 are embedded in the matrix 4 uniformly dispersed or in layers parallel to the backing 2 . In this setup, the binder 6 is used not only to bind the abrasive grains 8 in the matrix 4, but also to bond the matrix 4 to the backing 2, so no separate bond between the matrix 4 and the backing 2 is required layer.

Facing the side formed on the matrix 4 facing away from the backing 2 is a free contact surface 10 parallel to the backing 2 . The non-scarred abrasive particles 8 protrude slightly from the contact surface 10 (not shown) subjected to the return force of the elastically compliant adhesive 6 when the abrasive is not in use. In use, the abrasive grains in the region of the contact surface 10 interact with a workpiece (not shown) against the rebound force of the elastically compliant binder 6 , being completely or nearly completely compressed in the matrix 4 . However, in their original condition or prior to application of the abrasive, the abrasive grains 8 protrude beyond the contact surface only sufficiently to form a microstructure at the contact surface 10 together with the binder 6 of the matrix 4 .

In addition, the specific embodiments described are characterized in the following specific aspects:

Throughout the length of the backing 2, the matrix 4 is divided into a plurality of regular hexagonal matrix bodies 4a with surfaces defined by the hexagonal shape to be oriented perpendicularly to the backing 2 so that no matter how worn, the matrix 4 will become retained for each backing 2 or each matrix body 4a parallel to the contact surface 10 with the same regular hexagonal cross-section.

Each individual matrix body 4 a protrudes beyond the backing 2 with a full-length void 12 , which is sized all the way in the middle and extends from the backing 2 to the area of the contact surface 10 .

The void 12 can be used for air cooling or liquid cooling of the workpiece (not shown).

As shown, the matrix body 4a forms a uniform honeycomb structure of the matrix 4 . In this arrangement, the grinding direction 16 is selected so as to determine the direction along the imaginary line connecting the two opposite corners of the matrix body 4a, which are successively interleaved to form a gap so that even when the matrix body 4a is shaken, Mutual support by adjacent immobile matrix bodies 4a is still ensured.

Irrespective of the particular hexagonal configuration of the individual matrix bodies 4a shown in this case, their configuration and arrangement in the matrix 4 is chosen so as to facilitate the connection of the matrix 4 and the backing 2 decomposed into the individual matrix bodies 4a as a whole It enhances the flexibility of abrasive composites. This is a significant and unique advantage when the abrasive is an endless belt (not shown).

Test example:

Test parameters:

Tubestock belt grinder: Flex LBR 1506 VRA, 1200 Watt

Belt length (ring belt): 40mm×618mm

Cutting speed: 14m/s

Work piece: stainless steel pipe, material number No.1.4301,

Size: 50mm×2.5mm

Operation: Manually guide the machine through the pipe

Test preparation:

The stainless steel pipe is first ground coarsely on a centerless grinder with a grinding belt grain size P 80. The average peak-to-valley height after rough skiving is about Ra = 2.6 microns.

Run the test:

For stainless steel railings, the average peak-to-valley height Ra = 0.5 microns is usually defined. This is usually achieved by applying the following particle sequence: P120-P180-P280. Use an abrasive belt, eg the standard abrasive belt CS 310 XF (flexible cotton backing approx. 320 g/m ² , abrasive grains aluminum oxide, phenolic resin binder). To achieve a specific polish, the machine is run at least 3 times (grains P120-P180-P280).

For comparison, the endless belt of the present invention is used in the same test structure and carried out the same test preparation, the characteristics of the endless belt are as follows: flexible cotton backing about 320g/m ² , layer thickness of 1200 microns of polyurethane as non-porous thermoset Binder, abrasive grains silicon carbide P60 are evenly dispersed in the binder.

In only 1 run, the average peak to valley height Ra = 0.5 microns.

Claims (64)

1. An abrasive, wherein abrasive grains (8) are uniformly dispersed in a matrix (4) containing a non-foaming and non-porous thermosetting binder for said abrasive grains (8) (6), and wherein the contact surface (10) covered by abrasive grains (8) is designed for grinding a workpiece; It is characterized by a combination of the following characteristics: (a) the degree of elasticity and compliance of the matrix (4) makes the abrasive grains (8) covering the contact surface (10) pressed into the matrix (4) during grinding; (b) said abrasive particles (8) are dispersed in the matrix (4) such that consumption of the matrix (4) perpendicular to the contact surface (10) initially covered by the abrasive particles (8) releases the Covered deeper contact surfaces (10); (c) said abrasive particles (8) are dispersed in the matrix (4) such that they obey the resiliency of the matrix (4) perpendicular and parallel to the corresponding contact surface (10) of the abrasive; (d) the substrate (4) is bonded to the flexible backing (2); (e) The substrate (4) is directly bonded to its flexible backing (2) by means of an adhesive (6) contained within the substrate (4). 2. The abrasive material according to claim 1, characterized in that the density of the binder (6) in the matrix (4) is not lower than 90% of the specific gravity of the binder (6) substance. 3. The abrasive according to claim 1, characterized in that the elasticity of the matrix (4) is not less than 35%. 4. The abrasive according to claim 3, characterized in that the elasticity of the matrix (4) is not less than 40%. 5. The abrasive material according to claim 1, characterized in that, the elasticity of the matrix (4) is not greater than 55%. 6. The abrasive according to claim 5, characterized in that the elasticity of the matrix (4) is not greater than 50%. 7. The abrasive material according to claim 1, characterized in that, the hardness of the matrix (4) is not lower than 40 Shore A. 8. The abrasive material according to claim 7, characterized in that, the hardness of the matrix (4) is not lower than 45 Shore A. 9. The abrasive material according to claim 1, characterized in that, the hardness of the matrix (4) is not higher than 75 Shore A. 10. The abrasive material according to claim 9, characterized in that, the hardness of the matrix (4) is not higher than 70 Shore A. 11. The abrasive material according to claim 1, characterized in that, the ultimate elongation of the matrix (4) is not lower than 150%. 12. The abrasive according to claim 11, characterized in that, the ultimate elongation of the matrix (4) is not less than 170%. 13. The abrasive material according to claim 1, characterized in that the flexural rigidity of the backing (2) detected through a detection width of 15 mm, a detection distance of 20 mm and a rotation angle of 15° is not higher than 5000 mm ox. 14. The abrasive according to claim 1, characterized in that the thickness of the matrix perpendicular to the backing (2) is not less than 200 μm. 15. The abrasive according to claim 14, characterized in that the thickness of the matrix perpendicular to the backing (2) is not less than 500 μm. 16. The abrasive according to claim 15, characterized in that the thickness of the matrix perpendicular to the backing (2) is not less than 1000 μm. 17. The abrasive according to claim 1, characterized in that the thickness of the matrix perpendicular to the backing (2) is not higher than 2500 μm. 18. The abrasive according to claim 17, characterized in that the thickness of the matrix perpendicular to the backing (2) is not higher than 1500 μm. 19. The abrasive material according to claim 1, characterized in that, in the ratio of the volume percentage of the abrasive grains (8) to the volume percentage of the binder (6) of the matrix (4), the abrasive grains ( 8) The volume percentage is less than or equal to 80 volume%. 20. Abrasive according to claim 19, characterized in that, in the ratio of the volume percentage of the abrasive grains (8) to the volume percentage of the binder (6) of the matrix (4), the abrasive grains ( 8) The volume percentage is less than or equal to 60 volume%. 21. Abrasive according to claim 1, characterized in that, in the ratio of the volume percentage of the abrasive grains (8) to the volume percentage of the binder (6) of the matrix (4), the abrasive grains ( 8) The volume percentage is greater than or equal to 20 volume%. 22. Abrasive according to claim 21, characterized in that, in the ratio of the volume percentage of the abrasive grains (8) to the volume percentage of the binder (6) of the matrix (4), the abrasive grains ( 8) The volume percentage is greater than or equal to 40 volume%. 23. The abrasive material according to claim 1, characterized in that, the size of the abrasive particles (8) is 2-2000 μm. 24. The abrasive according to claim 23, characterized in that the size of the abrasive particles (8) is 70-540 μm. 25. Abrasive according to claim 24, characterized in that the abrasive grains (8) have dimensions P36, P60, P120 and P240 according to FEPA standards. 26. The abrasive material according to claim 1, characterized in that, the Shore hardness of the abrasive material in the Shore hardness A range is 60°-90° Shore A. 27. The abrasive according to claim 1, characterized in that the binder (6) contains polyurethane. 28. Abrasive material according to claim 27, characterized in that said binder (6) is made of one of said polyurethanes. 29. Abrasive according to claim 1, characterized in that the binder (6) contains rubber. 30. Abrasive material according to claim 29, characterized in that said binder (6) is made of one of said rubbers. 31. Abrasive material according to claim 1, characterized in that the binder (6) contains polysulfides. 32. Abrasive material according to claim 31, characterized in that said binder (6) is made of one of said polysulfides. 33. The abrasive according to claim 1, characterized in that the binder (6) contains acrylate. 34. Abrasive material according to claim 33, characterized in that said binder (6) is made of one of said acrylates. 35. Abrasive material according to claim 1, characterized in that the binder (6) is filled. 36. Abrasive material according to claim 1, characterized in that, in addition to the binder (6), the matrix (4) also contains at least one filler and/or at least one dye and/or at least one additive. 37. Abrasive material according to claim 35 or 36, characterized in that kaolin is provided as filler. 38. Abrasive material according to claim 35 or 36, characterized in that at least one foam suppressor is provided as additive. 39. Abrasive material according to any one of claims 1, 35 and 36, characterized in that the abrasive grains (8) contain at least one silicon carbide and/or at least one silicon dioxide. 40. Abrasive material according to claim 39, characterized in that the abrasive grains (8) consist of at least one silicon carbide and/or at least one silicon dioxide. 41. The abrasive according to any one of claims 1, 35 and 36, characterized in that the abrasive particles (8) consist of at least one alumina and/or at least one alumina mixed crystal. 42. Abrasive material according to any one of claims 1, 35 and 36, characterized in that at least a part of the abrasive grains (8) consists of at least one hard metal. 43. Abrasive material according to any one of claims 1, 35 and 36, characterized in that the abrasive particles (8) arranged closest to the backing (2) rest on the backing (2) superior. 44. Abrasive according to any one of claims 1, 35 and 36, characterized in that the matrix (4) including its abrasive grains (8) is divided and dispersed on the same backing (2) and mutually There are several matrix bodies (4a) spaced apart, said matrix bodies (4a) having a uniform cross-section in a direction perpendicular to the initial contact surface (10) or backing (2). 45. The abrasive material according to claim 44, characterized in that, the matrix body (4a) has a polygonal cross-section parallel to the backing (2), and is arranged in a staggered manner in the grinding direction (16). 46. The abrasive material according to claim 45, characterized in that, the polygonal cross-section is hexagonal, and two corners in the grinding direction (16) or opposite to the grinding direction (16) are used The two corner orientations in the direction. 47. The abrasive material according to claim 44, characterized in that, the matrix bodies (4a) have a circular cross-section parallel to the backing (2), and are arranged staggered with each other in the grinding direction (16). 48. The abrasive material according to any one of claims 1, 35 and 36, characterized in that the backing (2) consists of a woven fabric, a knitted fabric, a film and/or a filament layer. 49. Abrasive material according to claim 48, characterized in that the backing (2) consists of natural fibers or artificial fibers, or mixtures thereof. 50. The abrasive according to any one of claims 1, 35 and 36, characterized in that the backing (2) is inherently elastically compliant. 51. Abrasive material according to any one of claims 1 , 35 and 36, characterized in that the backing (2) has a quality finish. 52. The abrasive material of any one of claims 1, 35 and 36, wherein the abrasive structure is an endless belt. 53. The abrasive material of any one of claims 1, 35 and 36, wherein the abrasive structure is a flat material. 54. The abrasive material of claim 53, wherein the abrasive structure is a bar for an oscillating drive. 55. The abrasive material of any one of claims 1, 35 and 36, wherein the abrasive structure is a disc or bow for an oscillating drive. 56. The abrasive material of any one of claims 1 , 35 and 36, wherein the abrasive structure is a disc for a rotary drive, a segmented abrasive disc, laminated abrasive points or a wheel. 57. A method for manufacturing the abrasive material according to any one of claims 1-56, characterized in that firstly, the abrasive particles (8) are mixed into a matrix ( 4), the mixture is then applied to the backing (2). 58. A process for the manufacture of an abrasive material according to any one of claims 1-56, characterized in that the adhesive (6), which is still low in viscosity, is first applied to the matrix on the backing (2) ( 4) and then applied to the abrasive grains (8) so that the abrasive grains (8) sink into the backing (2) while the binder (6) is still of low viscosity. 59. The manufacturing method of abrasive according to claim 58, characterized in that, the abrasive grains (8) are dispersed in the matrix (4), while the binder (6) is still of low viscosity. 60. The method of manufacturing abrasives according to claim 58, characterized in that the abrasive grains (8) are applied in several ways to the matrix (4) previously applied to the backing (2), while sticking Mixture (6) is still low viscosity. 61. The method of manufacturing abrasives according to claim 57, characterized in that the matrix (4) containing the binder (6) and the abrasive grains (8) are applied to the backing together in a multi-layer coating method (2) up. 62. The manufacturing method of abrasive according to any one of claims 58-60, characterized in that, the substrate (4) containing the binder (6) and the abrasive grains (8) are coated in multiple layers Applied to the backing (2) by the coating method. 63. The manufacturing method of abrasive according to any one of claims 57-61, characterized in that, the matrix bodies (4a) arranged at intervals from each other are arranged on the backing (2) by using a masking technique. 64. A method for manufacturing abrasive materials according to any one of claims 44-47, characterized in that the matrix bodies (4a) arranged at intervals are arranged on the backing (2) by using a masking technique.

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