Silicon-ceramic inserts in grinding wear parts

Abstract

The invention relates to a wear part (1) for a mill, in particular a grinding roller or a grinding plate. The wear part (1) comprises a cast metal material (2) and a plurality of ceramic inserts (3). The ceramic inserts (3) are enclosed by the cast metal material (2). The ceramic inserts (3) comprise silicon-ceramic material. The invention also relates to a mill, to a method for producing a wear part (1) of a mill, and to the use of silicon-ceramic inserts (3) embedded in a cast metal material (2) in a wear part (1) of a mill.

Description

[0001] Silicon ceramic inserts in grinding wear parts

[0002] The present invention relates to a wear part for a mill, a mill, a method for producing a wear part for a mill and the use of silicon ceramic inserts embedded in a metal casting material in a wear part of a mill.

[0003] Wear parts of a mill, such as a grinding roller or grinding plate, are often exposed to severe abrasive stress and can therefore wear out quickly. The maintenance and replacement of these wear parts can represent a significant economic factor. On the one hand, the mill cannot be operated during this time, and on the other hand, the replacement itself can be associated with high costs.

[0004] Various methods for improving wear resistance are known in the prior art. For example, CN103111347A teaches the use of ceramic pins embedded in a steel base. DE112009003706T5 describes the use of wear plates made of hard metal or ceramic welded to a metal base. EP0476496B1 teaches the arrangement of rib-shaped wear inserts made of cast chromium in a metal matrix.

[0005] Due to the high and cyclical forces during the grinding process, the bond between the wear inserts and the matrix material is subjected to significant stress. A poor bond between the wear inserts and the metal matrix negatively impacts the durability of the wear parts.

[0006] One object of the present invention is to improve the wear resistance and durability of milling wear parts. Another object of the present invention is to ensure simple and reliable production of the milling wear parts.

[0007] According to a first aspect of the invention, a wear part for a mill comprises a cast metal material and a plurality of ceramic inserts. The ceramic inserts are surrounded by the cast metal material, in particular embedded therein. The ceramic inserts comprise silicon ceramic.

[0008] The metal casting material acts primarily as a joint compound between the ceramic inserts. Due to the high mechanical stresses acting on the wearing part, the metal casting material must be particularly wear-resistant. Otherwise, the metal casting material will wear away significantly faster than the ceramic inserts during use of the wearing part, resulting in gaps between the ceramic inserts. Furthermore, the metal casting material should exhibit a certain degree of ductility in order to embed the ceramic inserts sufficiently firmly. Cracks in the metal casting material, for example, caused by temperature differences, fatigue, and / or brittle fracture, can impair the anchoring of the ceramic inserts in the metal casting material. Sufficient ductility of the metal casting material can prevent or reduce the formation of cracks. However, excessive ductility can negatively impact wear resistance.To achieve the object of the invention, it is important, among other things, to find a good compromise between the ductility and wear resistance of the metal casting material. Furthermore, it is important to select the metal casting material and the material of the inserts in such a way as to reduce cracks caused by different expansion coefficients and / or elastic moduli of the different materials.

[0009] The wear part can be a grinding roller or a grinding plate. The grinding roller can have a radius of 90 millimeters to 1500 millimeters, preferably 250 millimeters to 1250 millimeters. The radius of the grinding roller is defined in particular as the radial distance from the rotational axis of the grinding roller to the working surface of the grinding roller. The grinding plate can have a radius of 200 millimeters to 3600 millimeters, preferably 500 millimeters to 3350 millimeters. The radius of the grinding plate is defined in particular as the radial distance from the center of the grinding plate to an outer edge of the grinding plate.

[0010] The ceramic inserts may have a substantially polygonal cross-section. The polygonal cross-section may have eight or more corners. The polygonal cross-section may be a regular polygonal cross-section. The polygonal cross-section may not have re-entrant corners. The cross-section may be the shape of the ceramic inserts in a plane orthogonal to an axial direction of the ceramic inserts.

[0011] The ceramic inserts may comprise an upper base surface and a lower base surface. The upper base surface may be arranged in a surface of the wear part. The lower base surface may be arranged inside the wear part.

[0012] The ceramic inserts can extend from the lower base surface to the upper base surface. The ceramic inserts can extend along an axial direction from the lower base surface to the upper base surface. The upper base surface can have an octagonal or polygonal cross-section.

[0013] The ceramic inserts may have lateral surfaces. The lateral surfaces may extend from the upper base surface to the lower base surface.

[0014] During use, the upper base surface can face the material to be ground. The upper base surface can face away from the center of gravity of the wearing part. The wearing part can be a grinding roller. The ceramic inserts of the grinding roller can be arranged such that the upper base surface faces away from the center of gravity of the grinding roller. The lower base surface can face the center of gravity of the grinding roller. The upper base surface can be arranged on the grinding surface of the grinding roller. The wearing part can be a grinding plate. The upper base surface of the ceramic inserts can be arranged on the top side of the grinding plate. The top side of the grinding plate can be in contact with the material to be ground when the grinding plate is used as intended. During use, the upper base surface of the ceramic inserts can be in contact with the material to be ground.

[0015] The wear part may have a working surface. The working surface may be a grinding surface of a grinding roller or a grinding plate. During the intended use of the wear part, the working surface may face the material to be ground, in particular, it may be in contact with the material to be ground.

[0016] The grinding roller can have a radial direction. The axial direction of the ceramic inserts can correspond to the radial direction or be parallel to it.

[0017] The working surface can be designed to act on the material to be ground, particularly in cooperation with a working surface of another wear part. The upper base surface of the ceramic inserts can be arranged in the working surface.

[0018] The ceramic inserts may form at least 50 percent, preferably at least 75 percent, preferably at least 90 percent of the working surface.

[0019] The ceramic inserts can be formed essentially as a prism or truncated pyramid between the lower base surface and the upper base surface. The prism, cylinder, or truncated pyramid can extend along the axial direction of the ceramic inserts. The ceramic inserts can have a notch. The notch can extend in the circumferential direction of the ceramic inserts. The notch can preferably be arranged near the lower base surface.

[0020] The notch may have a depth of 1 millimeter to 20 millimeters, preferably 2 millimeters to 15 millimeters, preferably 3 millimeters to 7 millimeters. The depth of the notch may be defined as the radial distance between the lateral surface in which the notch is located and the innermost point of the notch.

[0021] The notch may have a width of 1 millimeter to 20 mm, preferably 3 millimeters to 15 millimeters, preferably 5 millimeters to 10 millimeters. The width of the notch may be defined as the extension of the notch along the lateral surface in the axial direction of the ceramic inserts.

[0022] The notch can cover 1 percent to 50 percent of the surface area, 2 percent to 25 percent of the surface area, preferably 3 percent to 20 percent of the surface area, preferably 5 percent to 15 percent of the surface area.

[0023] The notches can be rounded. The notches can be designed as part-circular or circular-segment-shaped notches. The notches have a part-circular or circular-segment-shaped geometry, particularly in a sectional view. The notches can have a radius of 2 millimeters to 20 mm, in particular 3 millimeters to 10 mm, in particular 4 millimeters to 7 millimeters. The notches can be formed by a thread, in particular an external thread. The notches can have the shape of a thread, in particular an external thread. The thread can be a left-hand thread or a right-hand thread.

[0024] The ceramic inserts may have lateral surfaces. The lateral surfaces may extend between the lower and upper base surfaces. The lateral surfaces may be arranged substantially orthogonally to the axial direction of the ceramic inserts. The ceramic inserts may have a shape that tapers toward the lower base surface. The lateral surfaces may extend at an angle to the axial direction. The notch may be arranged in the lateral surfaces of the ceramic inserts.

[0025] The notch can extend substantially orthogonally to the axial direction of the ceramic insert. The notch can extend continuously around the ceramic insert. The notch can run continuously around the ceramic insert. The notch can have a plurality of interruptions. For example, the notch can be interrupted at one point. The notch can be interrupted at two points, which are arranged in particular on opposite lateral surfaces. The notch can be interrupted at three, four, five or more points. The interruptions in the notch can be evenly distributed in the circumferential direction.

[0026] The notches can be designed such that they do not extend across the entire lateral surface. The notches can be designed such that they do not extend from the lower base surface to the upper base surface.

[0027] Two adjacent surfaces of a ceramic insert can form an angle of more than 120 degrees. The two surfaces can form an angle of 135 degrees or greater.

[0028] The ceramic inserts, or a single ceramic insert, can have eight lateral surfaces. The lateral surfaces are all arranged at substantially the same angle to the adjacent lateral surface. For example, a first lateral surface can have an angle of 135 degrees to a second lateral surface. The second lateral surface can have an angle of 135 degrees to a third lateral surface. The third lateral surface can have an angle of 135 degrees to a fourth lateral surface, and so on.

[0029] The lateral surfaces of a ceramic insert can be arranged such that none of the angles enclosed between two adjacent lateral surfaces is less than 120 degrees, in particular less than or equal to 120 degrees. The lateral surfaces of a ceramic insert can be arranged such that each of the angles between two lateral surfaces of a ceramic insert is greater than or equal to 120 degrees, in particular greater than 120 degrees. The lateral surfaces of a ceramic insert can be arranged such that none of the angles enclosed between two adjacent lateral surfaces is less than 135 degrees. The lateral surfaces of a ceramic insert can be arranged such that each of the angles enclosed between two lateral surfaces of a ceramic insert is at least 135 degrees, in particular substantially exactly 135 degrees.

[0030] The angle values ​​mentioned above can have a positive effect on the fatigue and fracture behavior of the metal casting material. A shallow angle results in a relatively mild notch in the metal casting material. The angles mentioned above can have a positive effect on the manufacturing process of the ceramic inserts. The angles mentioned above can have a positive effect on the bond between the ceramic inserts and the metal casting material.

[0031] The cross-section of the ceramic inserts may not have any re-entrant corners. The lateral surfaces of a ceramic insert may be arranged in the shape of a convex polygon. The cross-section of the ceramic inserts may be a convex polygon. The cross-section of the ceramic inserts may be a regular polygon. The cross-section of the ceramic inserts may be a regular octagon. The cross-section of the ceramic inserts may be a regular hexagon.

[0032] The ceramic inserts can have a height between 10 millimeters and 50 millimeters, preferably between 15 millimeters and 40 millimeters, preferably between 20 millimeters and 30 millimeters. The height of the ceramic inserts can be defined as the distance between the lower base surface and the upper base surface in the axial direction of the ceramic inserts.

[0033] The ceramic inserts can have a diameter between 10 millimeters and 100 millimeters, preferably between 25 millimeters and 75 millimeters, preferably between 40 millimeters and 50 millimeters. The diameter of a ceramic insert can be defined as the distance between two opposite lateral surfaces, particularly in the radial direction. The radial direction can be arranged orthogonally to the axial direction. The diameter can run through the center of the cross-section of the ceramic insert.

[0034] The edges between two adjacent surfaces of a ceramic insert can be rounded. The edges between two adjacent surfaces of a ceramic insert can be chamfered.

[0035] The edge between the outer surface of a ceramic insert and the notch of the ceramic insert can be rounded and / or chamfered. The edge between the outer surfaces of a ceramic insert and the notch of the ceramic insert can be rounded and / or chamfered. The rounded or chamfered edges, both between adjacent outer surfaces and between the outer surface and the notch, can have a positive effect on the fatigue and fracture behavior of the cast metal material. The rounded or chamfered edges cause a relatively mild notch in the cast metal material.

[0036] Each of the ceramic inserts may have a lower portion and an upper portion. The lower portion may include the lower base surface. The upper portion may include the upper base surface. The boundary between the lower portion and the upper portion may be defined by the notch.

[0037] The upper section may have a cross-sectional area substantially equal to that of the lower section. The upper section may have a cross-sectional area substantially identical to that of the lower section. The lower section may have a smaller cross-sectional area than the upper section. The lower section may have a diameter between 5 millimeters and 90 millimeters, preferably between 20 millimeters and 70 millimeters, preferably between 40 millimeters and 45 millimeters. The upper section may have a diameter between 10 millimeters and 100 millimeters, preferably between 25 millimeters and 75 millimeters, preferably between 40 millimeters and 50 millimeters.

[0038] The lower section can have a height between 1 millimeter and 25 millimeters, preferably between 3 millimeters and 20 millimeters, preferably between 5 millimeters and 15 millimeters. The height of the lower section can be defined as the distance from the lower base surface to the edge or center of the notch in the axial direction of the ceramic inserts.

[0039] The upper section can have a height between 5 millimeters and 50 millimeters, preferably between 10 millimeters and 40 millimeters, preferably between 15 millimeters and 30 millimeters. The height of the upper section can be defined as the distance from the upper base surface to the edge or center of the notch in the axial direction of the ceramic inserts.

[0040] The lower portion of the ceramic insert may have recesses. The recesses may extend into the notch. The recesses may extend substantially in the axial direction of the ceramic insert. The recesses may extend substantially in the axial direction of the ceramic insert.

[0041] The lower region of the ceramic insert can be hollow. The cavity of the lower region can extend substantially in the axial direction. The lower region of the ceramic insert can be annular. The annular lower region of the ceramic insert can have a wall thickness. The recess can extend over part of the wall thickness of the lower region. The recess can extend over the entire wall thickness of the lower region. The recesses can have a positive effect on the bond between the ceramic insert and the metal casting material.

[0042] The ceramic inserts can have a multitude of point-shaped notches. The point-shaped notches can be arranged flatly in the lateral surfaces. The point-shaped notches can be arranged across the entire lateral surfaces. The ceramic inserts can have grid-shaped notches. The lateral surfaces of the ceramic inserts can have grid-shaped notches over their entire surface.

[0043] The ceramic inserts can have a fastening point in the form of a fastening bow, fastening handle, or fastening grip. The fastening bow can be arranged in the lower region of the ceramic inserts. The fastening bow can be attached to at least one point on the lower base surface. The fastening bow can be attached to one, two, or more points on the lower base surface. The fastening bow can extend away from the lower base surface. A cavity can be formed between the fastening bow and the lower base surface. The cavity can have a positive effect on the bond between the ceramic insert and the metal casting material.

[0044] The ceramic inserts can be mushroom-shaped, in particular comprising a mushroom head and a mushroom base. The mushroom head can have a larger diameter than the mushroom base. The mushroom head can be arranged in the work surface. The mushroom head can comprise the upper base area. The mushroom base can comprise the lower base area.

[0045] The metal casting material can be arranged in the notch of the ceramic insert(s). This notch allows for a good bond between the metal casting material and the ceramic insert. The metal casting material can be arranged in the cavity between the mounting bracket and the lower base surface. The cavity between the mounting bracket and the lower base surface allows for a good bond between the metal casting material and the ceramic insert.

[0046] The ceramic inserts are arranged in the wear part. The ceramic inserts can be arranged regularly in the wear part. The ceramic inserts can be arranged uniformly in the wear part. The distance between two ceramic inserts in the wear part can be essentially constant. The lateral surfaces of two adjacent ceramic inserts in the wear part can be arranged parallel.

[0047] The distance between two adjacent ceramic inserts, in particular between two lateral surfaces of adjacent ceramic inserts, can be between 1 millimeter and 15 millimeters, preferably between 2 millimeters and 10 millimeters, preferably between 3 millimeters and 8 millimeters. The ceramic inserts can consist essentially of silicon ceramic. The ceramic inserts can comprise a silicon-carbon compound, in particular silicon carbide. The ceramic inserts can comprise a silicon-carbon compound, in particular silicon carbide. The ceramic inserts can comprise a silicon-nitrogen compound, in particular silicon nitride. The ceramic inserts can comprise a silicon-nitrogen compound, in particular silicon nitride.

[0048] The ceramic inserts may comprise at least 70 mass percent, preferably 80 mass percent, preferably 90 mass percent, silicon carbide or silicon nitride.

[0049] The metal casting material may comprise high-alloy, wear-resistant cast iron. The metal casting material may comprise nickel-chilled cast iron. The metal casting material may consist essentially of high-alloy, wear-resistant cast iron. The metal casting material may consist essentially of nickel-chilled cast iron.

[0050] The metal casting material may comprise white-setting cast iron, in particular wear-resistant white-setting cast iron. The metal casting material may consist of white-setting cast iron. The nickel chill cast iron may be Ni-Hard, in particular Ni-Hard IV. The metal casting material may contain 8 mass percent to 10 mass percent chromium. The metal casting material may contain 3 mass percent to 7 mass percent, preferably 4 mass percent to 6.5 mass percent, preferably 4.5 mass percent to

[0051] 5.5 mass percent nickel. The metal casting material can contain 1.5 mass percent to

[0052] 2.5 mass percent silicon. The metal casting material can essentially contain 9 mass percent chromium, 5 mass percent nickel, and 2 mass percent silicon.

[0053] The ceramic inserts may have a recess, in particular a central recess. The recess may extend in the axial direction of the ceramic inserts. The recess may extend from the lower base surface to the upper base surface. The recess may have a wear indicator.

[0054] The recess may have a diameter of 2 millimeters to 20 millimeters, preferably 3 millimeters to 15 millimeters, preferably 5 millimeters to 10 millimeters.

[0055] The recess can be a hole. The central recess can be a central hole.

[0056] The bore, in particular the central bore, can have a diameter of 2 millimeters to 20 millimeters, preferably 3 millimeters to 15 millimeters, preferably 5 millimeters to 10 millimeters.

[0057] The ceramic inserts can have an anti-rotation element. The recess, in particular the central recess, can represent a first recess. The distance between the first recess and the anti-rotation element can be 10 percent to 80 percent, preferably 15 percent to 60 percent, preferably 20 percent to 40 percent, of the diameter of the ceramic insert.

[0058] The anti-rotation element can be designed, in particular in cooperation with the first recess, to prevent or counteract rotation of the ceramic insert, in particular about an axial direction of the ceramic insert. The anti-rotation element can be a second recess, which runs in particular parallel to the first recess. The second recess can extend from the lower base surface to the upper base surface. The second recess can be a bore. The second recess can have a diameter of 2 millimeters to 20 millimeters, preferably 3 millimeters to 15 millimeters, preferably 5 millimeters to 10 millimeters. The second recess can in particular be designed identically to the first recess.

[0059] The anti-rotation element can be a cam. The cam can extend from the lower base surface of the ceramic insert, in particular in the axial direction of the ceramic insert.

[0060] The ceramic inserts can be attached to a casting mold by means of a rivet and the first recess and / or the second recess. In particular, the ceramic inserts are attached to the casting mold via both the first recess and the second recess by a rivet each.

[0061] The ceramic inserts can have a first groove on the lower base surface. The first groove runs, in particular, in a straight line. The first groove can extend between two opposite lateral surfaces of the ceramic insert, in particular between a first lateral surface and a second lateral surface. The first groove can have a depth of at least 1 millimeter, preferably 2 millimeters, preferably 3 millimeters. The first groove can have a depth between 1 millimeter and 10 millimeters.

[0062] The ceramic inserts can have a second groove on the lower base surface in addition to the first groove. The second groove runs in particular in a straight line. The second groove can extend between two opposite lateral surfaces of the ceramic insert, in particular between a third lateral surface and a fourth lateral surface. The second groove can have a depth of at least 1 millimeter, preferably 2 millimeters, preferably 3 millimeters. The second groove can have a depth between 1 millimeter and 10 millimeters. The second groove can have the same dimensions as the first groove.

[0063] The first and the second groove can be arranged at an angle to one another. The angle between the first and the second groove can be between 30 degrees and 90 degrees, in particular between 50 degrees and 70 degrees, preferably about 60 degrees. The first and the second groove can have an intersection point, wherein the intersection point is arranged in particular in the middle of the lower base area. The first groove and / or the second groove can be designed to receive a wire, in particular in the form of a wire grid or wire mesh. By arranging the wire or the wire grid or wire mesh in the grooves, the individual ceramic inserts can be arranged and aligned with one another. By arranging the wire or the wire grid or wire mesh in the grooves, rotation of the ceramic inserts about the axial direction can be prevented or hindered.The wire mesh can have a diamond-shaped arrangement of the individual wires. The individual wires of the wire mesh or wire mesh can be arranged at an angle of between 30 degrees and 90 degrees, in particular between 50 degrees and 70 degrees, preferably approximately 60 degrees, to one another.

[0064] The wire mesh or wire mesh can comprise a plurality of first wires. The first wires run in particular parallel to one another and are arranged at a distance of between 10 millimeters and 150 millimeters, preferably between 25 millimeters and 100 millimeters, preferably between 35 millimeters and 50 millimeters. The distance between the first wires is in particular 101 percent to 150 percent, preferably between 105 percent to 130 percent, of the diameter of the ceramic inserts.

[0065] The wire mesh or wire mesh can comprise a plurality of second wires. The second wires run in particular parallel to one another and are arranged at a distance of between 10 millimeters and 150 millimeters, preferably between 25 millimeters and 100 millimeters, preferably between 35 millimeters and 50 millimeters. The distance between the first wires is in particular 101 percent to 150 percent, preferably between 105 percent to 130 percent, of the diameter of the ceramic inserts. The shortest distance between the second wires is in particular greater than the shortest distance between the first wires.

[0066] The ceramic inserts can be arranged in a plurality of rows. The individual rows can be arranged offset from one another. Adjacent rows can each be arranged offset from one another. The offset between two adjacent rows can be half the diameter of a ceramic insert and the distance between two adjacent ceramic inserts. The distance between two adjacent ceramic inserts within a row can be substantially equal to the distance between two adjacent rows. A second row of ceramic inserts can be arranged offset by a first distance from a first row of ceramic inserts. A third row of ceramic inserts can be arranged offset by the first distance from the second row of ceramic inserts. The first row of ceramic inserts can be aligned with the second row of ceramic inserts. The ceramic inserts can alternatively be rib-shaped or bar-shaped.The rib-shaped or bar-shaped ceramic inserts can extend substantially between a first side surface and a second side surface along a longitudinal direction. The distance between the first side surface and the second side surface can be greater than the distance between the lower base surface and the upper base surface. The longitudinal direction can be orthogonal to the axial direction. The extension of the ceramic insert in the longitudinal direction can be greater than the extension of the ceramic insert in the axial direction.

[0067] According to one embodiment of the invention, the ceramic inserts consist essentially of silicon nitride. The ceramic inserts, in particular the upper base surfaces of the ceramic inserts, have a regular octagonal or hexagonal cross-section. The metal casting material consists essentially of nickel chill casting, in particular Ni-Hard.

[0068] The plural and singular terms "ceramic inserts" are used synonymously in the above and following descriptions. Therefore, the use of the term "ceramic insert" does not imply that the features described in this context are limited to a single ceramic insert. When features are described with reference to a single ceramic insert, the skilled person will understand that the remaining ceramic inserts may be of the same design.

[0069] In one embodiment, the ceramic inserts can have a thread. The metal casting material can have a matching thread. The ceramic inserts can be cast around the metal casting material or screwed into the solidified and cooled metal casting material after the casting process. The metal casting material and the ceramic inserts have, in particular, different expansion coefficients. If the ceramic inserts are already cast around the metal casting material, cracks can occur in the metal casting material during cooling, which are particularly due to different expansions in the metal casting material and the ceramic inserts. Subsequent screwing in of the ceramic inserts can, in particular, prevent crack formation in the metal casting material. The thread in the metal casting material can be created during the casting process, in particular by means of placeholders or Croning cores. Alternatively, the thread can be subsequently cut into the metal casting material.The ceramic inserts of this embodiment, in particular, have a round cross-section. The ceramic inserts can be designed in the shape of a countersunk screw. A conical section can be formed below the upper base surface, which is in particular round. An additional closure region extending in the axial direction of the screw can also be formed on the head of the countersunk screw. The additional wear region is in particular cylindrical. The additional wear region, in particular, provides more wearable material, thereby increasing the service life of the wearing part. The remaining features described above also apply to this embodiment, provided these features do not contradict each other.

[0070] According to a second aspect of the invention, a mill comprises a wear part according to the first aspect of the invention.

[0071] The mill may have a grinding plate. The grinding plate may be a wear part according to the first aspect of the invention. The mill may have one or more grinding rollers. The one or more grinding rollers may be wear parts according to the first aspect of the invention.

[0072] According to a third aspect of the invention, a method for manufacturing a wear part of a mill comprises providing a casting mold for the wear part, arranging ceramic inserts in the casting mold, and pouring metal casting material into the casting mold.

[0073] The ceramic inserts can be designed as described in the first aspect of the invention.

[0074] The ceramic inserts can consist essentially of a silicon-carbon compound, in particular silicon carbide. The ceramic inserts can consist essentially of a silicon-nitrogen compound, in particular silicon nitride.

[0075] The ceramic inserts may essentially have an octagonal or polygonal cross-section. The ceramic inserts may have a regular cross-section, in particular a regular octagonal or hexagonal cross-section.

[0076] The method can further comprise attaching the ceramic inserts to a carrier mesh. The ceramic inserts can be attached to a carrier mesh. The carrier mesh can then be introduced into the casting mold. The ceramic inserts can be aligned in the casting mold using the carrier mesh. The ceramic inserts can be aligned within the casting mold using a sheet metal template. The ceramic inserts can be attached to a wire, wire grid or wire mesh and / or aligned within the casting mold using the wire, wire grid or wire mesh, in particular in cooperation with the first and / or second grooves of the ceramic inserts. The wire, wire grid or wire mesh can be at least indirectly attached in the first and / or second grooves of the ceramic inserts, in particular glued, snapped or clipped therein. Nodes of the wire grid orThe wire mesh can be arranged in the recesses, particularly the central recesses, of the ceramic inserts. The wire mesh or wire mesh can have a diamond-shaped arrangement of the individual wires. The ceramic inserts can have an opening. The ceramic inserts can be attached to the casting mold by means of a fastening means penetrating the opening. The ceramic inserts can have a bore, particularly a central bore. The ceramic inserts can be attached to the casting mold by means of a screw or rivet arranged in the bore.

[0077] The method may comprise providing a second casting mold, in particular a plurality of second casting molds. The method may comprise casting the ceramic inserts in the second casting mold, in particular the plurality of second casting molds. Casting the ceramic inserts may precede arranging the ceramic inserts in the casting mold.

[0078] The method may further comprise forming green compacts, in particular made of silicon nitride or silicon carbide. The method may further comprise sintering the green compacts into ceramic inserts.

[0079] According to one embodiment, the metal casting material is initially poured into the casting mold without ceramic inserts. After the metal casting material has solidified, the ceramic inserts can be screwed into the metal casting material. For this purpose, the ceramic inserts in particular have a thread. The metal casting material also has a thread. The thread in the metal casting material can be formed during the casting process. In particular, placeholders, in particular in the form of Croning cores, are placed in the casting mold before the metal casting material is poured into the casting mold. The placeholders can in particular have largely the same shape as the ceramic inserts to be inscribed. Alternatively, the thread can be cut into the metal casting material after the casting process. The ceramic inserts can be designed as described at the end of the first aspect of the invention.

[0080] A fourth aspect of the invention comprises the use of silicon ceramic inserts embedded in a metal casting material in a wear part of a mill. The wear part can be a grinding roller. The wear part can be a grinding plate.

[0081] The ceramic inserts can be designed as described in the first aspect of the invention. The metal casting material can be designed as described in the first aspect of the invention.

[0082] The following statements relate to the first aspect, the second aspect, the third aspect and the fourth aspect of the invention.

[0083] The ceramic inserts can be dense. The ceramic inserts can be solid. The ceramic inserts can be made of solid ceramic.

[0084] The ceramic inserts can have a density of 2 grams per cubic centimeter (g / cm 3) to 4 grams per cubic centimeter, preferably 2.5 grams per cubic centimeter to 3.5 grams per cubic centimeter, preferably 3.1 grams per cubic centimeter to 3.3 grams per cubic centimeter.

[0085] The ceramic inserts can be essentially pore-free. The ceramic inserts can have a pore content of less than 5 volume percent, preferably less than 3 volume percent, preferably less than 1 volume percent. The ceramic inserts can have a pore content of less than 0.1 volume percent.

[0086] The ceramic inserts can consist essentially of silicon ceramic. The ceramic inserts can comprise a silicon-carbon compound, in particular silicon carbide. The ceramic inserts can comprise a silicon-carbon compound, in particular silicon carbide. The ceramic inserts can comprise a silicon-nitrogen compound, in particular silicon nitride. The ceramic inserts can comprise a silicon-nitrogen compound, in particular silicon nitride.

[0087] The ceramic inserts can contain at least 70 mass percent silicon, preferably 80 mass percent silicon, preferably 90 mass percent silicon, in particular in the form of silicon carbide or silicon nitride. The ceramic inserts can contain at least 70 mass percent, preferably 80 mass percent, preferably 90 mass percent, silicon carbide or silicon nitride.

[0088] The metal casting material may comprise high-alloy, wear-resistant cast iron. The metal casting material may comprise nickel-chilled cast iron. The metal casting material may consist essentially of high-alloy, wear-resistant cast iron. The metal casting material may consist essentially of nickel-chilled cast iron.

[0089] The metal casting material may comprise white-setting cast iron, in particular wear-resistant white-setting cast iron. The metal casting material may consist of white-setting cast iron. The nickel chill cast iron may be Ni-Hard, in particular Ni-Hard IV. The metal casting material may contain 8 mass percent to 10 mass percent chromium. The metal casting material may contain 3 mass percent to 7 mass percent, preferably 4 mass percent to 6 mass percent, preferably 4.5 mass percent to

[0090] 5.5 mass percent nickel. The metal casting material can contain 1.5 mass percent to

[0091] 2.5 mass percent silicon. The metal casting material can essentially contain 9 mass percent chromium, 5 mass percent nickel, and 2 mass percent silicon.

[0092] The metal casting material, in particular nickel chill casting, can comprise a metal matrix. The metal casting material, in particular nickel chill casting, can comprise eutectic carbides. The metal casting material, in particular nickel chill casting, can comprise a metal matrix and eutectic carbides. The carbides can be formed during pouring of the metal casting material into the casting mold, in particular during solidification of the metal casting material. Eutectic carbides are, in particular, carbides that are formed directly from the melt during the solidification of a metal or alloy. Eutectic carbides are formed in particular when the eutectic temperature is reached, according to the invention at 1600 degrees Celsius to 1100 degrees Celsius, preferably at 1495 degrees Celsius to 1140 degrees Celsius.

[0093] A eutectic reaction is understood to mean, in particular, rapid solidification at a defined temperature, the eutectic temperature, which leads, in particular, to a uniform microstructure. In particular, a liquid phase solidifies directly into two or more solid phases without the formation of an intermediate phase.

[0094] Eutectic carbides are very hard and / or wear-resistant. The wear behavior of the wear part is particularly improved by the presence of eutectic carbides. The metal casting material can, for example, contain chromium carbides. The eutectic carbides can be chromium carbides.

[0095] The wear part according to the first aspect of the invention can be manufactured using method steps of the method according to the third aspect of the invention. The mill according to the second aspect of the invention can comprise one or more wear parts according to the first aspect of the invention. The method according to the third aspect of the invention can be used to produce a wear part according to the first aspect of the invention. The components described in the method, in particular the ceramic inserts and / or the metal casting material, can be designed as described in the context of the first aspect of the invention.

[0096] The use according to the fourth aspect of the invention may comprise the method or method steps according to the third aspect of the invention. The use according to the fourth aspect of the invention may be carried out with a wear part according to the first aspect of the invention.

[0097] As used in the description of the various embodiments described and the appended claims, the singular forms are to be construed as including the plural forms and vice versa, unless the context clearly indicates otherwise.

[0098] The terms "first," "second," "third," and "fourth" are merely designations for a specific element or component and do not necessarily indicate a particular order or arrangement of the components or elements mentioned. For example, the presence of a fourth element / component does not necessarily imply the presence of a first, second, or third element / component, and vice versa.

[0099] Advantageous embodiments of the invention are explained in more detail below with reference to the accompanying figures. Figure 1 shows a perspective view of a wear part according to the invention in the form of a grinding roller.

[0100] Fig. 2 shows a perspective view of a ceramic insert according to the invention shown in Fig. 1.

[0101] Fig. 3 shows a side view of the ceramic insert shown in Fig. 2.

[0102] Fig. 4 shows a plan view of a section of the working surface of the grinding roller shown in Fig. 1.

[0103] Fig. 5 shows a perspective view and a side view of another embodiment of a ceramic insert according to the invention.

[0104] Fig. 6 shows a perspective view and a side view of another embodiment of a ceramic insert according to the invention.

[0105] Fig. 7 shows a perspective view and a side view of another embodiment of a ceramic insert according to the invention.

[0106] Fig. 8 shows a perspective view and a side view of another embodiment of a ceramic insert according to the invention.

[0107] Fig. 9 shows a perspective view and a side view of another embodiment of a ceramic insert according to the invention.

[0108] Fig. 10 shows a perspective view and a side view of another embodiment of a ceramic insert according to the invention.

[0109] Fig. 11 shows a perspective view and a side view of another embodiment of a ceramic insert according to the invention.

[0110] Fig. 12 shows a perspective view and a side view of another embodiment of a ceramic insert according to the invention.

[0111] Fig. 13 shows a perspective view of another embodiment of a wear part according to the invention in the form of a grinding roller.

[0112] Fig. 14 shows a perspective view of a ceramic insert according to the invention shown in Fig. 13.

[0113] Fig. 15 shows a side view of the ceramic insert shown in Fig. 14.

[0114] Fig. 16 shows a perspective view of another embodiment of a ceramic insert according to the invention.

[0115] Fig. 17 shows a perspective view of another embodiment of a ceramic insert according to the invention.

[0116] Fig. 18 shows a perspective view of another embodiment of a ceramic insert according to the invention.

[0117] Fig. 19 shows a bottom view of an arrangement according to the invention of the ceramic inserts 3 shown in Fig. 18 on a wire mesh. Fig. 1 shows a perspective view of a wear part 1 according to the invention in the form of a grinding roller. The grinding roller 1 has a cast metal material 2 and a plurality of ceramic inserts 3. The ceramic inserts 3 are surrounded by the cast metal material 2 or embedded therein. The grinding roller 1 has a working surface 4. The working surface 4 is also referred to as the grinding surface. In the intended use of the grinding roller 1, the working surface 4 faces the material to be ground. The working surface 4 is arranged in the radially outer region of the grinding roller 1. The ceramic inserts 3 or the upper base surfaces 5 of the ceramic inserts 3 are arranged in the working surface 4. The upper base surfaces 5 of the ceramic inserts 3 form the working surface 4. The ceramic inserts 3 have a regular octagonal cross-section.Other cross-sectional shapes, such as a regular hexagon, are also possible.

[0118] 2 and 3 show a perspective view and a side view, respectively, of a ceramic insert 3 according to the invention shown in Fig. 1. The ceramic insert 3 has an upper base surface 5 and a lower base surface 6. The upper base surface 5 is arranged opposite the lower base surface 6. The ceramic insert 3 extends along an axial direction 100 between the lower base surface 6 and the upper base surface 5. The upper base surface 5 has a regular octagonal cross-section. The lower base surface 6 has a regular octagonal cross-section. The ceramic insert has eight lateral surfaces 7. The lateral surfaces 7 extend between the lower base surface 6 and the upper base surface 5. A notch 8 is arranged in the lateral surfaces 7. The notch 8 runs in the circumferential direction around the ceramic insert 3.In embodiments, the notch 8 can be interrupted and / or arranged only in some lateral surfaces 7. The notch 8 divides the ceramic insert 3 into an upper section 9 and a lower section 10. The upper section 9 comprises the upper base surface 5. The lower section 10 comprises the lower base surface 6.

[0119] Fig. 4 shows a plan view of a section of the working surface 4 of the grinding roller 1 shown in Fig. 1. The working surface 4 is shown in a developed form, i.e. without curvature. Fig. 4 shows in particular the arrangement of the ceramic inserts 3 or the upper base surfaces 5 in the cast metal material 2. A first distance 50 between two ceramic inserts 3 is between 7 millimeters and 8 millimeters. A second distance 51 between two ceramic inserts 3 is between 3 millimeters and 4 millimeters. The diameter 52 of the ceramic inserts 3, in particular the distance between two opposite outer surfaces 7, is 45 millimeters. The ceramic inserts 3 are arranged in rows. In the section shown in Fig. 4, each row comprises three ceramic inserts 3. Adjacent rows are offset from one another by an offset distance 53. The offset distance 53 is between 26 millimeters and 27 millimeters.A second row 12 is arranged adjacent to a first row 11. The second row 12 is arranged offset from the first row 11 by the offset distance 53. A third row 13 is arranged adjacent to the second row 12. The third row 13 is arranged offset from the second row 12 by the offset distance 53. The third row 13 is aligned with the first row 11, or the ceramic inserts 3 of the third row 13 are aligned with the ceramic inserts 3 of the first row 11. A total of six rows are shown in Fig. 4. The first row 11, the third row 13 and the fifth row 15 are arranged aligned with one another. The second row 12, the fourth row 14 and the sixth row 16 are arranged aligned with one another.

[0120] Fig. 5 shows a perspective view and a side view of a further embodiment of a ceramic insert 3 according to the invention. In comparison to the embodiment shown in Figs. 2 and 3, the ceramic insert 3 in Fig. 5 has a central recess 17 in the form of a central bore. The recess 17 or the bore is arranged centrally only in the embodiments shown, but can also be arranged at a different location. The central bore 17 extends in the axial direction 100 from the lower base surface 6 to the upper base surface 5. The central bore 17 is arranged centrally in the upper base surface 5 and the lower base surface 6. However, the embodiment can also be designed without a central bore 17. In comparison to the embodiment in Figs. 2 and 3, the upper section 9 also has a lower height.

[0121] Fig. 6 shows a perspective view and a side view of another embodiment of a ceramic insert 3 according to the invention. Compared to the embodiment shown in Fig. 5, the ceramic insert 3 has a first rounded portion 18 between the lower portion 10 and the notch 8. The edges between the lateral surfaces 7 of the lower portion 10 and the notch 8 are rounded. Furthermore, the lower portion 10 has a circular cross-section.

[0122] The ceramic insert 3 can also be designed without a central bore 17. The ceramic insert 3 can also be designed without a first rounded portion 18. The cross-section of the lower section 10 can be octagonal, in particular identical to the cross-section of the upper section 9.

[0123] Fig. 7 shows a perspective view and a side view of a further embodiment of a ceramic insert 3 according to the invention. Compared to the embodiment shown in Fig. 6, the ceramic insert 3 has second rounded portions 19 between the upper section 9 and the notch 8. The edges between the lateral surfaces 7 of the upper section 9 and the notch 8 are rounded. In addition, the ceramic insert 3 has third rounded portions 20 between adjacent lateral surfaces 7 of the upper section 9. The edges between adjacent lateral surfaces 7 of the upper section 9 are rounded. The ceramic insert 3 can also be designed without a central bore 17, or with two bores 17 or recesses 17. The cross section of the lower section 10 can be octagonal, in particular identical to the cross section of the upper section 9. The ceramic insert 3 can also be designed without a first rounded portion 18.The ceramic insert 3 can also be designed without a second rounding 19. The ceramic insert 3 can also be designed without a third rounding 20.

[0124] Fig. 8 shows a perspective view and a side view of another embodiment of a ceramic insert 3 according to the invention. Compared to the embodiment shown in Fig. 6, the lower section 10 of the ceramic insert 3 has a smaller diameter than the upper section 9. The lower base surface 6 has a smaller diameter than the upper base surface 5. The ceramic insert has a mushroom shape.

[0125] The ceramic insert 3 can also be designed without a central bore 17. The cross-section of the lower section 10 can be octagonal, in particular identical to the cross-section of the upper section 9. The ceramic insert 3 can also be designed without a first rounded portion 18. The ceramic insert 3 can also be designed without a second rounded portion 19. The ceramic insert 3 can also be designed without a third rounded portion 20.

[0126] Fig. 9 shows a perspective view and a side view of another embodiment of a ceramic insert 3 according to the invention. Compared to the embodiment shown in Fig. 8, the lower section 10 of the ceramic insert 3 has a cavity 21. The cavity 21 extends in the axial direction 100 from the lower base surface 6 into the notch 8. The cavity 21 extends to the edge of the upper section 9. The lower section 10 is thus annular. The lower section 10 further has four recesses 22. The recesses 22 are evenly distributed in the circumferential direction of the ceramic insert 3. The recesses 22 extend over part of the wall thickness of the annular lower region 10.

[0127] The ceramic insert 3 can also be designed with a central bore 17. The cross-section of the lower section 10 can be octagonal, in particular identical to the cross-section of the upper section 9. The ceramic insert 3 can also be designed without a first rounded portion 18. The ceramic insert 3 can also be designed without a second rounded portion 19. The ceramic insert 3 can also be designed without a third rounded portion 20. The lower section 10 and the upper section 9 can have the same diameter. The lower base surface 6 and the upper base surface 5 can have the same diameter. The ceramic insert 3 can also be designed without a cavity 21. The ceramic insert 3 can also be designed without recesses 22.

[0128] Fig. 10 shows a perspective view and a side view of another embodiment of a ceramic insert 3 according to the invention. Compared to the embodiment shown in Fig. 9, the recesses 22 extend over the entire wall thickness of the lower section 10.

[0129] The ceramic insert 3 can also be designed with a central bore 17. The cross-section of the lower section 10 can be octagonal, in particular identical to the cross-section of the upper section 9. The ceramic insert 3 can also be designed without a first rounded portion 18. The ceramic insert 3 can also be designed without a second rounded portion 19. The ceramic insert 3 can also be designed without a third rounded portion 20. The lower section 10 and the upper section 9 can have the same diameter. The lower base surface 6 and the upper base surface 5 can have the same diameter. The ceramic insert 3 can also be designed without a cavity 21. The ceramic insert 3 can also be designed without recesses 22.

[0130] Fig. 10 shows a perspective view and a side view of another embodiment of a ceramic insert 3 according to the invention. The ceramic insert 3 has an upper base surface 5 and a lower base surface 6. The upper base surface 5 is arranged opposite the lower base surface 6. The ceramic insert 3 extends along an axial direction 100 between the lower base surface 6 and the upper base surface 5. The upper base surface 5 has a regular octagonal cross-section. The lower base surface 6 has a regular octagonal cross-section. The ceramic insert has eight lateral surfaces 7. The lateral surfaces 7 extend between the lower base surface 6 and the upper base surface 5. The ceramic insert has a central recess in the form of a central bore 17. The central bore 17 extends in the axial direction 100 from the lower base surface 6 to the upper base surface 5.The lateral surfaces 7 have grid-shaped notches. The grid-shaped notches are distributed over the entire surface of the lateral surfaces 7. The lower base surface 6 has grid-shaped notches. The grid-shaped notches are distributed over the entire surface of the lower base surface 6.

[0131] The ceramic insert 3 can also be designed without a central bore 17. The ceramic insert 3 can have any features and combinations of features of the embodiments shown in Figs. 2 to 10.

[0132] Fig. 11 shows a perspective view and a side view of a further embodiment of a ceramic insert 3 according to the invention. The ceramic insert 3 has an upper base surface 5 and a lower base surface 6. The upper base surface 5 is arranged opposite the lower base surface 6. The ceramic insert 3 extends along an axial direction 100 between the lower base surface 6 and the upper base surface 5. The upper base surface 5 has a regular octagonal cross-section. The lower base surface 6 has a regular octagonal cross-section. The ceramic insert has eight lateral surfaces 7. The lateral surfaces 7 extend between the lower base surface 6 and the upper base surface 5. In addition, the ceramic insert 3 has third roundings 20 between adjacent lateral surfaces 7. The edges between adjacent lateral surfaces 7 are rounded. The ceramic insert 3 has a fastening arc 23.The mounting bracket 23 is attached to the lower base surface 6 at two locations. The mounting handle 23 extends from the lower base surface 6, in particular in the axial direction 100. A second cavity 24 is formed between the mounting bracket 23 and the lower base surface 6.

[0133] The ceramic insert 3 can have any features and combinations of features of the embodiments shown in Figs. 2 to 11.

[0134] The ceramic inserts 3 of the wear part 1 according to the invention, shown in Fig. 1, in the form of a grinding roller, can be designed according to any of the embodiments shown in Figs. 2 to 12. Those skilled in the art will understand that any combinations are also possible, meaning that the wear part 1 can also have ceramic inserts 3 of different embodiments.

[0135] Fig. 13 shows a perspective view of a further embodiment of a wear part 1 according to the invention in the form of a grinding roller. The grinding roller 1 has a cast metal material 2 and a plurality of ceramic inserts 3. The ceramic inserts 3 are surrounded by the cast metal material 2 or embedded therein. The grinding roller 1 has a working surface 4. The working surface 4 is also referred to as the grinding surface. In the intended use of the grinding roller 1, the working surface 4 faces the material to be ground. The working surface 4 is arranged in the radially outer region of the grinding roller 1. The ceramic inserts 3 or the upper base surfaces 5 of the ceramic inserts 3 are arranged in the working surface 5. The upper base surfaces 5 of the ceramic inserts 3 form the working surface 5. The ceramic inserts 3 are rib-shaped or bar-shaped.

[0136] 14 and 15 show a perspective view and a side view, respectively, of a ceramic insert 3 according to the invention shown in Fig. 13. The ceramic insert 3 has an upper base surface 5 and a lower base surface 6. The upper base surface 5 is arranged opposite the lower base surface 6. The ceramic insert 3 extends along an axial direction 100 between the lower base surface 6 and the upper base surface 5. The ceramic insert 3 further has two lateral surfaces 7. The lateral surfaces 7 are arranged opposite one another and extend essentially in the axial direction 100 or slightly inclined thereto between the upper base surface 5 and the lower base surface 6.

[0137] The ceramic insert 3 extends between a first side surface 24 and a second side surface 25 along a longitudinal direction 200, which is oriented orthogonally to the axial direction 100. The first side surface 24 and the second side surface 25 are arranged substantially orthogonally to the longitudinal direction 200. The distance between the first side surface 24 and the second side surface 25 is greater than the distance between the lower base surface 6 and the upper base surface 5. The extension of the ceramic insert 3 in the longitudinal direction 200 is greater than the extension of the ceramic insert 3 in the axial direction 100.

[0138] Each of the two lateral surfaces 7 has a notch 8. The notches 8 each extend in the longitudinal direction 200 from the first side surface 24 to the second side surface 25.

[0139] 16 and 17 show perspective views of further embodiments of ceramic inserts 3 according to the invention. In comparison to the ceramic inserts 3 shown previously, the ceramic inserts 3 shown in Figs. 16 and 17 have a round upper base surface 5. In particular, the ceramic inserts 3 have the shape of a countersunk screw. The ceramic inserts 3 can have a conical section 26, which extends in particular away from the upper base surface 5 counter to the axial direction 100. In the embodiment shown in Fig. 17, an additional wear region 27 is formed between the upper base surface 5 and the conical region 5. The additional wear region 27 is cylindrical and has the same diameter as the upper base surface 5. The ceramic inserts 3 further have a threaded region 28. The threaded region 28 has a thread 29, which is formed in particular into the outer surface of the threaded region 28.The threaded region 28 can border on the conical region 26. In embodiments without a conical region 26, the threaded region 28 can border on the additional wear region 27. A notch 30 can be formed in the upper base surface 5, in particular in the center of the upper base surface 5. The notch 30 can have the shape of a regular hexagon. In particular, the notch 30 can be designed to be engaged with a tool, in particular an (internal) hexagon wrench or Allen key. The notch 30 can be designed to transmit a rotation of the tool to the ceramic insert 3, which in particular enables the ceramic insert 3 to be screwed into the wearing part 1 or the metal casting matrix 2.

[0140] Fig. 18 shows a perspective view of a further embodiment of a ceramic insert 3 according to the invention. The ceramic insert 3 has a first groove 31 and a second groove 32 on the lower base surface 6. The ceramic insert 3 can also have only the first groove 31. The first groove 31 and the second groove 32 have an intersection point 33. The intersection point 33 is arranged centrally in the lower base surface 6 and lies in the recess 17. However, this does not have to be the case. The ceramic insert 3 can also be designed without a recess 17. The intersection point 33 can also not be arranged centrally. The first groove 31 and / or second groove 32 shown in Fig. 18 can be designed in any of the embodiments shown in Figs. 2, 3 and 5 to 11.

[0141] Fig. 19 shows a bottom view of an inventive arrangement of the ceramic inserts 3 shown in Fig. 18 on a wire mesh 34 or wire mesh 34. The wire mesh 34 comprises a plurality of first wires 35 running parallel to one another. Adjacent first wires 35 are spaced apart from one another by a first wire spacing 60. The wire mesh 34 comprises a plurality of second wires 36 running parallel to one another. Adjacent second wires 36 are spaced apart from one another by a second wire spacing 61. The first wire spacing 60 is smaller than the second wire spacing 61.

[0142] The first wires 35 are arranged at an angle 62 to the second wires 36. The first wires 35 and second wires 36 form, in particular, a diamond pattern. The first wires 35 cross the second wires 36 at wire intersection points 37. The wire intersection points 37 coincide with the intersection points 33 between the first grooves 31 and second grooves 32 of the ceramic inserts 3 and can, in particular, be fastened therein, for example, glued. The first wires 35 are arranged in the first grooves 31 of the ceramic inserts 3. The second wires 36 are arranged in the second grooves 32 of the ceramic inserts 3 and can, in particular, be fastened therein, for example, glued, snapped, or clipped.

Claims

Claims 1. Wear part (1) for a mill, in particular a grinding roller or a grinding plate, comprising a metal casting material (2) and a plurality of ceramic inserts (3), wherein the ceramic inserts (3) are surrounded by the metal casting material (2), wherein the ceramic inserts (3) comprise silicon ceramic, and wherein the metal casting material (2) comprises white-solidifying cast iron.

2. Wear part according to claim 1, wherein the ceramic inserts (3) have a substantially polygonal cross-section with eight or more corners.

3. Wear part according to claim 1 or 2, wherein the ceramic inserts (3) are formed substantially as a prism or truncated pyramid between a lower base surface (6) and an upper base surface (5), wherein the ceramic inserts (3) have a notch (8) extending in the circumferential direction of the ceramic inserts (3), wherein the notch (8) is preferably arranged in the vicinity of the lower base surface (6).

4. Wear part according to one of the preceding claims, wherein the ceramic inserts (3) have lateral surfaces (7) which extend from a lower base surface (6) to an upper base surface (5), wherein none of the angles enclosed between two lateral surfaces (7) of a ceramic insert (3) is less than 120 degrees, preferably less than or equal to 120 degrees, preferably less than 135 degrees.

5. Wear part according to one of the preceding claims, wherein the ceramic inserts (3) consist essentially of a silicon-carbon compound or a silicon-nitrogen compound, in particular of silicon carbide or silicon nitride.

6. Wear part according to one of the preceding claims, wherein the ceramic inserts (3) comprise at least 70 mass percent, preferably at least 90 mass percent, of silicon carbide or silicon nitride.

7. Wear part according to one of the preceding claims, wherein the metal casting material (2) comprises nickel chill casting, in particular Ni-Hard.

8. Wear part according to one of the preceding claims, wherein the ceramic inserts (3) have a recess (17), in particular in the axial direction (100) of the ceramic inserts (3) extending, and preferably have an anti-rotation element, in particular in the form of a second recess or a cam.

9. Mill comprising a wear part (1) according to one of the preceding claims.

10. A method for producing a wear part (1) for a mill, in particular for producing a grinding roller or a grinding plate, comprising: - Providing a casting mold for the wear part (1), - arranging ceramic inserts (3) in the casting mould, and - Pouring metal casting material (2) into the casting mold, wherein the ceramic inserts (3) comprise silicon ceramic, and wherein the metal casting material (2) comprises white-setting cast iron.

11. The method according to claim 10, wherein the ceramic inserts (3) consist essentially of a silicon-carbon compound or a silicon-nitrogen compound, in particular of silicon carbide or silicon nitride.

12. Method according to claim 10 or 11, wherein the ceramic inserts (3) have a substantially octagonal or polygonal cross-section.

13. Method according to one of claims 10 to 12, wherein the ceramic inserts (3) are fastened to a carrier net, a wire grid or a wire mesh and / or are aligned by means of a sheet metal template, a wire grid or a wire mesh within the casting mold.

14. Use of silicon ceramic inserts (3) embedded in a metal casting material (2) in a wear part (1) of a mill, in particular in a grinding roller or a grinding plate, wherein the metal casting material (2) comprises white-solidifying cast iron.

15. Wear part according to one of claims 1 to 8, mill according to claim 9, method according to one of claims 10 to 13, or use according to claim 14, wherein the ceramic inserts (3) have a density of 2 grams per cubic centimeter (g / cm 3 ) to 4 grams per cubic centimeter, in particular 2.5 grams per cubic centimeter to 3.5 grams per cubic centimeter, in particular 3.1 grams per cubic centimeter to 3.3 grams per cubic centimeter.

16. Wear part according to one of claims 1 to 8, mill according to claim 9, method according to one of claims 10 to 13, or use according to claim 14, wherein the metal casting material comprises 3 mass percent to 7 mass percent, in particular 4 mass percent to 6.5 mass percent, in particular 4.5 mass percent to 5.5 mass percent, of nickel.

17. Wear part according to one of claims 1 to 8, mill according to claim 9, method according to one of claims 10 to 13, or use according to claim 14, wherein the ceramic inserts (3) have on a lower base surface (6) a first groove (31) extending between two opposite lateral surfaces (7) of the ceramic insert (3), and a second groove (32) extending between two opposite lateral surfaces (7) of the ceramic insert (3).

18. Wear part according to one of claims 1 to 8, mill according to claim 9, method according to one of claims 10 to 13, or use according to claim 14, wherein the metal casting material (2) comprises eutectic carbides.

Images