Anvil roll and rotary cutter

Abstract

To provide an inexpensive and long-life anvil roll and a rotary cutter.SOLUTION: A rotary cutter 1 has: a cutter roll 2 having a cutting blade 21; and an anvil roll 3 which is a blade receiving part 31 smooth in a circumferential direction of the roll, and has a circumferential surface 34, where at least the circumferential surface 34 is made of cermet obtained by blending materials such that a mass ratio by each element becomes Ti:20 to 45%, Mo:10 to 40%, W:10 to 35%, C:5 to 15%, Co:10 to 40%, Co and Ni in total: 25 to 40%, mixing the materials to obtain mixed powder, press-molding the mixed powder to obtain a pressed body, and sintering the pressed body.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a rotary cutter that has a cutter roll with a cutting blade and an anvil roll with a blade receiving portion, and cuts a strip-shaped workpiece, which is an object to be cut sandwiched between them, into a desired cutting blade pattern. The present invention also relates to an anvil roll.

Background Art

[0002] As a type of cutting and punching device, there is known a rotary cutter that has a cutter roll with a cutting blade and an anvil roll that contacts the blade receiver of the cutting blade, and cuts a strip-shaped workpiece, which is an object to be cut sandwiched between them, into a desired pattern shape of the cutting blade. Hard materials are used for the cutting blade of the rotary cutter and the blade receiving portion of the anvil roll to improve wear resistance.

[0003] Patent Document 1 describes that by using a cemented carbide or cermet having a specific Young's modulus for the blade receiving portion of the anvil roll, it is possible to achieve both chipping resistance of the cutting edge of the cutting blade and wear resistance.

[0004] Patent Documents 2 to 5 describe that a cermet such as a Ti-based alloy may be used for the cutting edge portion of the cutting blade of the cutter roll or the anvil roll.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Non-Patent Documents

[0006]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0007] Regarding the anvil rolls described in Patent Document 1 to Patent Document 5, generally, the problems are considered to be reducing the wear of the anvil roll and preventing the cutting edge of the cutting blade of the cutter roll from chipping. It is described that the material of the anvil roll capable of solving these problems is cemented carbide or cermet. On the other hand, regarding the cermet material itself, there is no description, or generally, the range of materials called "cermet" is described as it is, and the composition of the cermet optimal for the anvil roll is not specified. For example, in Patent Document 1, regarding cermet, only the general composition of cermet is shown as "As the cermet contained in the hard material, those containing at least one selected from the group consisting of Mo, Ni, and Ti as the metal component and containing at least one of carbide and nitride as the ceramic component can be mentioned. As the carbide, for example, TiC can be mentioned. As the nitride, for example, TiN can be mentioned. The metal contained in the cermet may be an alloy containing at least one selected from the group consisting of Mo, Ni, and Ti". In Patent Document 5, only the basic properties such as hardness and Young's modulus are described together with a rough composition.

[0008] These prior art documents suggest that a wide range of cermets can be applied to the surface of the anvil roll, but the inventors have found that the cermet suitable for the anvil roll surface has a limited composition. In addition, an anvil roll particularly suitable for the case where cemented carbide is used for the cutting edge of the cutting blade of the cutter roll has been found. In the present application, an object is to obtain an inexpensive and long-life anvil roll and a rotary cutter by using a cermet sintered body having a specific composition for at least the blade receiving portion of the anvil roll.

Means for Solving the Problems

[0009] The present invention is has a circumferential surface that is a smooth blade receiving portion in the circumferential direction of the roll, at least the circumferential surface is made of a cermet sintered body, the cermet is mass ratio of elements is , Ti (titanium) 20 to 45% Mo (molybdenum) 10 to 40% W (tungsten) 10 to 35% C (carbon) 5 to 15% Co (cobalt) 10 to 40% Co + Ni (nickel) 15 to 40% so that, using powders arbitrarily selected from Ti or Ti compounds, Mo or Mo compounds, W or W compounds, Co or Co compounds, Ni or Ni compounds and carbon as raw materials, mixing them wet or dry to obtain a mixed powder, pressing the mixed powder at a pressure of 50 to 300 MPa to obtain a pressed body, obtained through the step of sintering the pressed body at 1300 to 1700 °C in an atmosphere of vacuum, reduction, inert gas, hydrogen or nitrogen , having three phases: a core phase mainly composed of Ti(C,N), a rim phase mainly composed of (Ti,Mo,W)(C,N) that exists so as to cover the periphery of the core phase, and a metal phase, and the average particle size of the hard phase composed of the core phase and the rim phase in cross-sectional microstructure observation is less than 3 μm By making it an anvil roll made of cermet, the above-mentioned problem was solved.

[0010] Also, a cutter roll having a cutting blade, has a circumferential surface that is a smooth blade receiving portion in the circumferential direction of the roll, and at least the blade receiving portion is made of a cermet sintered body, the cermet is mass ratio of elements is , Ti (titanium) 20 to 45% Mo (Molybdenum) 10 - 40% W (Tungsten) 10 - 35% C (Carbon) 5 - 15% Co (Cobalt) 10 - 40% Co + Ni (Nickel) 15 - 40% Powders arbitrarily selected from Ti or Ti compounds, Mo or Mo compounds, W or W compounds, Co or Co compounds, Ni or Ni compounds, and carbon are used as raw materials so that they are mixed wet or dry to obtain a mixed powder, the mixed powder is press - formed at a pressure of 50 - 300 MPa to obtain a pressed body, the pressed body is obtained through a step of sintering in an atmosphere of any one of 1300 - 1700 °C, vacuum, reduction, inert gas, hydrogen, or nitrogen , having three phases: a core phase mainly composed of Ti(C,N), a rim phase mainly composed of (Ti,Mo,W)(C,N) that exists so as to cover the periphery of the core phase, and a metal phase, and the average particle size of the hard phase composed of the core phase and the rim phase in cross-sectional microstructure observation is less than 3 μm Cermet is having an anvil roll, and the work, which is the object to be cut sandwiched between the cutting edge of the cutter roll and the circumferential surface of the anvil roll, the cutter roll and the anvil roll is cut into a desired cutting - edge pattern by the rotary motion of

Advantages of the Invention

[0011] The present invention has the following advantages. (1) Wear of the blade - receiving part of the anvil roll can be suppressed to the same level as that of an anvil roll made of cemented carbide. (2) It is significantly lighter than an anvil roll made of cemented carbide and can have a weight equal to or less than that of a steel material. (3) The manufacturing cost can be suppressed compared to an anvil roll made of cemented carbide.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Mode for Carrying Out the Invention

[0013] The rotary cutter of the present invention can be implemented in the following manner. (1) Overall configuration As shown in FIG. 1, the rotary cutter 1 has two rolls, a cutter roll 2 and an anvil roll 3. The cutter roll 2 has a cutting blade 21 on its circumferential surface, and the cutting blade 21 has a pattern of a desired shape for cutting the workpiece A in the circumferential direction. As shown in FIG. 6, the cutting blade generally has a substantially triangular shape. The anvil roll 3 has a blade receiving part 31 made of a cylindrical cermet on its circumferential surface, which serves as the blade receiving part for the cutting blade 21. The two rolls are generally fixed by inserting the central axis into bearings provided in the frame and are rotatably fixed. With the circumferential surfaces of the two rolls in contact, one or both of the rolls are rotated by a motor or the like, so that the two rolls rotate in opposite directions. At this time, a load may be applied in the direction of approaching the two rolls by a cylinder or the like. The cutting blade of the cutter roll and the blade receiving part of the anvil roll rotate continuously without a gap or with a slight gap. By passing the strip-shaped workpiece A to be cut between the two, the workpiece is cut by the cutting blade and the blade receiving part and then discharged after being pushed through the pattern of the cutting blade.

[0014] (2) Regarding the cutter roll As shown in Fig. 2, the cutter roll 2 uses a roll in a cylindrical or columnar shape. The cutter roll 2 has a central axis 23 that serves as the rotation center, and a circumferential surface 24 that has a cutting blade which contacts the blade receiving portion of the anvil roll 3 directly or via the workpiece. The cutting blade 21 is configured in a pattern for cutting or punching out the workpiece A which is the object to be cut. Cemented carbide may be used for the cutting blade 21. Cemented carbide has a significantly higher hardness compared to quenched steel, can reduce the frequency of regrinding the cutting blade and replacing the roll, and contributes to productivity. Also, the cutting blade 21 may use quenched steel in consideration of cost and the difficulty of workpiece cutting. At the end of the circumferential surface 24, there may be a guide ring 22 that protrudes toward the anvil roll side more than the circumferential surface 24 so as to easily adjust the "protrusion amount" of the cutting blade 21 described later. When using cemented carbide for the circumferential surface 24, since the cutting blade 21 is hard and contacts the circumferential surface 34 of the anvil roll 3 directly or via the workpiece A in a narrow area, when attempting high-speed cutting or continuous operation for a long time, high wear resistance is also required for the anvil roll.

[0015] (3) Regarding the anvil roll As shown in Fig. 3, the anvil roll 3 is in a cylindrical or columnar shape (Fig. 3 shows the case of a columnar shape), and its blade receiving portion 31 is smooth and contacts the cutting edge of the cutting blade 21 of the cutter roll directly or via the workpiece A. Regarding the central axis 33, it may or may not be provided, and it can also be structured without it if there are other fixing means. At least, the blade receiving portion 31 of the anvil roll 3 is a cermet, and the cermet has, by mass ratio of elements, Ti (titanium) 20 - 45% Mo (molybdenum) 10 - 40% W (tungsten) 10 - 35% C (carbon) 5 - 15% Co (cobalt) 10 - 40% Co + Ni (nickel) 15 - 40% It is a cermet obtained through steps of using, as raw materials, powders arbitrarily selected from Ti or Ti compounds, Mo or Mo compounds, W or W compounds, Co or Co compounds, Ni or Ni compounds, and carbon, mixing them wet or dry to obtain a mixed powder, press-molding the mixed powder at a pressure of 50 to 300 MPa to obtain a pressed body, and sintering the pressed body at 1300 to 1700 °C in an atmosphere of either vacuum, reduction, inert gas, hydrogen, or nitrogen. Even for cermets with the same composition, when only the coated surface formed by thermal spraying or the like is used as the flank portion 31, peeling is likely to occur due to contact with the cutting blade 21, and it is necessary to use a sintered body.

[0016] The composition of the cermet needs to be within the above range. As shown in FIG. 4, the cermet preferably has a structure having a core phase 81, a rim phase 82, and a metal phase 84. By weight, C (carbon) is 5 to 15%, which improves sinterability and forms a hard phase composed of a fine core phase and rim phase. If C is less than 5%, a sufficient volume of the core phase and rim phase will not be generated and the wear resistance will decrease. On the other hand, if C is added in an amount more than 15%, a free carbon phase will occur and the mechanical properties (strength, hardness, impact resistance) will be significantly reduced. Mo is 10 to 40 %, and W is 10 to 35%, and they are mixed within this range. The wettability between TiCN forming the core phase and Co and Ni forming the metal phase is poor, but the wettability of the hard phase composed of the core phase and rim phase can be improved by the rim phase generated by adding Mo2C or WC. This increases the sinterability of the material and can improve the mechanical properties (chipping resistance, wear resistance). By making the total of Mo and W 20 to 45%, an alloy of W and Co, Mo and Co, or W and Mo and Co will not be formed, the impact resistance is improved, and surface roughness of the anvil roll circumferential surface (flank portion) during use can be prevented. The total of Co and Ni is 15 to 40%. When the amount of metal is less than this range, the impact resistance becomes insufficient, and the circumferential surface (blade receiving part) of the anvil roll is likely to become rough. Conversely, when it is more than 40%, the wear resistance decreases, and the life of the anvil roll cannot be sufficiently extended. Also, Co is set to 10 to 40%. By setting Co within this range, the mechanical properties of the circumferential surface (blade receiving part) of the anvil roll can be improved, and its life can be extended.

[0017] In order to obtain the cermet having the above composition, for example, the following means are used. That is, the mass ratio of each element is Ti: 20 to 45% Mo: 10 to 40% W: 10 to 35% C: 5 to 15% Co: 10 ~40% The total of Co and Ni is 15 ~40% Steps of using, as raw materials, powders arbitrarily selected from Ti or Ti compounds, Mo or Mo compounds, W or W compounds, Co or Co compounds, Ni or Ni compounds, and carbon so that the above ratios are obtained, mixing them wet or dry to obtain a mixed powder, Steps of press-molding the mixed powder at a pressure of 50 to 300 MPa to obtain a pressed body, Steps of sintering the pressed body at 1300 to 1700 °C in any atmosphere of vacuum, reduction, inert gas, hydrogen, or nitrogen.

[0018] In the case of wet mixing, a volatile solvent such as ethanol is used as the solvent, and the slurry is dried by vacuum static drying, spray drying, or the like. At this time, the particle size of the particles forming the core phase and the rim phase after raw material mixing is desirably 2 μm or less, preferably 1.0 μm or less, and more preferably 0.6 μm or less. In the subsequent sintering process, although the particle size increases as sintering progresses, by setting it to 2 μm or less, it is possible to make the average particle size of the hard phase of the sintered body 3 μm or less under appropriate sintering conditions. Also, by setting it to 1.0 μm or less, it is possible to lower the sintering temperature, and the wear resistance can be further improved by atomization. Furthermore, by setting it to 0.6 μm or less, sintering can be performed at a lower temperature, and the wear resistance can be further improved accordingly. The obtained fine powder is mixed with a resin component serving as a molding binder and granulated. Spray drying may be used for granulation. The granulated powder is press-molded at 50 to 300 MPa using a die press or a hydrostatic press. After press molding, the pressed body is subjected to a debinding and pre-sintering treatment in a vacuum or gas atmosphere at 600 to 1000 °C for intermediate processing. In addition, when the intermediate processing is easy, the intermediate processing may be performed on the pressed body as it is without pre-sintering. Next, the pre-sintered body or the pressed body is sintered. The sintering conditions are carried out in a vacuum or gas atmosphere at 1300 to 1700 °C. Debinding and pre-sintering and the main sintering may be carried out continuously. Furthermore, hot isostatic pressing is performed as necessary to complete the sintered body. Finally, it is finished to the final shape by machining such as a cylindrical grinding machine or an internal grinding machine, or electrical machining to obtain a cylindrical cermet sintered body. This sintered body forms at least the circumferential surface of the target anvil roll.

[0019] (Microstructure of cermet used for anvil roll circumferential surface) As shown schematically in the cross-sectional structure 8 in Fig. 4, the cermet used in the present invention has three phases: a core phase 81 mainly composed of Ti(C,N), a rim phase 82 existing so as to cover the periphery of the core phase 81 and mainly composed of (Ti,Mo,W)(C,N), and a metal phase 83. It is desirable that the average grain size of the hard phase composed of the core phase and the rim phase in the cross-sectional structure observation is less than 3 μm. By making the average grain size of the hard phase composed of the core phase and the rim phase less than 3 μm, the mechanical properties and impact resistance are improved, so that it is not easily broken when an impact is applied, such as contact with the cutting edge of the cutting blade. In particular, by making the average grain size of the hard phase 1.5 μm or less, the hardness is further improved and the wear resistance is also improved. The core phase is a hard phase mainly composed of TiCN and has high hardness. The rim phase exists so as to cover the periphery of the core phase and is mainly composed of (Ti , Mo,W)(C,N). As shown in Fig. 5, the rim phase may have two phases: a phase with relatively more Mo and W components and a phase with relatively more Ti. When the rim phase has two phases, the hardness of the rim phase is improved and the wear resistance becomes higher.

[0020] The cermet constituting the anvil roll circumferential surface according to the present embodiment has a specific gravity of 9 or less. When the specific gravity of the member exceeds 9, adverse effects such as the occurrence of deflection of the central axis, an increase in the load on the drive device side, and the inability to cope with the enlargement of the device occur. When the specific gravity becomes 8 or less, it can be handled in the same way as steel materials, and when the specific gravity further becomes 7.5 or less, it becomes lighter than steel materials, and the degree of freedom in device design can be increased.

[0021] The cermet having the above characteristics has an impact resistance as high as that of cemented carbide, while having a specific gravity equivalent to that of steel materials and a wear resistance equivalent to that of cemented carbide, and can be manufactured at a lower cost than cemented carbide. It is inexpensive because the cost per volume of WC (tungsten carbide) used as the main component in cemented carbide is high.

[0022] Conventional anvil rolls are made of steel materials such as quenched steel, cemented carbide, or cermet. Among these, cermet has not been put into practical use. Generally, cermet is a material developed for cutting tool applications. It has a very high hardness, but its impact resistance is low accordingly. Therefore, when used on the circumferential surface of an anvil roll, when exposed to contact with the cutting edge of a discontinuous cutting blade, roll vibration, or irregular impacts, a large number of small-scale (about several to several tens of μm) peeling and surface roughness will occur at the contact part early on, leading to cutting defects. Therefore, it is difficult to extend the service life. On the other hand, the cermet within the above composition range has a higher metal (Co, Ni) content than general cermets, and long service life can be achieved while avoiding these problems.

[0023] The circumferential surface 34 of the anvil roll 3 is preferably formed of a sintered body of the cermet with a thickness of at least 0.5 mm. If it is less than 0.5 mm, there is a risk of breakage due to local compression by the cutting edge of the cutting blade. The thickness can be about 50 - 150 mm depending on the size of the anvil roll.

[0024] The central axis 33 is preferably made of quenched steel. The central axis 33 and the cylindrical cermet 31 can be joined and integrated by known means such as shrink fitting, press fitting, diffusion bonding, or adhesion.

[0025] The present invention will be described in more detail with the following examples.

Examples

[0026] First, the raw material powders shown in Example 1 of Table 1 were pulverized and mixed by an attritor using ethanol as a solvent. The obtained slurry was dried in a vacuum, mixed with paraffin as a binder, and then a pressed body was produced by press molding. Table 2 shows the mass % of the composition decomposed by element for the composition of Table 1. This pressed body was pre-sintered at 800 °C in an atmospheric pressure hydrogen atmosphere, and then sintered at 1400 °C in a vacuum atmosphere to obtain the cermet used for the anvil roll and rotary cutter of the present invention. The cermet obtained according to Example 1 had an average particle size of 1.2 μm. The examples and comparative examples after Example 2 were sintered at the lowest temperature at which the highest density was obtained within the range of 1300 to 1500°C. Other conditions were the same as those in Example 1. Also, in the examples and comparative examples (excluding cemented carbide and SKD11), the average particle size of the hard phase composed of the core phase and the rim phase was less than 2.5 μm.

[0027] The elemental composition ratio of the entire cermet structure deviated greatly from the raw material composition, and the coefficient of determination between the raw material composition and the component ratio of the cermet after sintering was low, making it impossible to accurately quantify. For reference, Table 3 shows the quantitative analysis results of the cermet of Example 1 by EPMA and EDX, and the deviation from the raw material composition can be confirmed. For this reason, it is considered that the change in the lattice state due to the formation of solid solutions between the constituent elements is affecting. As described in the above Non-Patent Document 1, it is also known that it is difficult to quantify the alloy composition of cermet materials in past studies, and accurate quantification is difficult. Thus, in the present invention, it is impossible or approximately impractical to directly identify the object by its structure or characteristics, and there are so-called "impossible and impractical situations" in the present invention.

[0028]

Table 1

[0029]

Table 2

[0030]

Table 3

[0031] Subsequently, the mechanical properties of the cermet produced were evaluated by the measurement methods shown below. Also, the same tests were conducted on cemented carbide and SKD as comparative materials. The measurement results are shown in Table 4.

[0032]

Table 4

[0033] The wear resistance test was conducted by the following method. First, two rolls used for a rotary cutter were prepared. One is a cutter roll with a diameter of 150 mm, and the cutting edge has a linear (concentric circle) pattern in the circumferential direction. The outer peripheral part of the cutter roll including the cutting edge is formed of cemented carbide (classified as VF-30 according to the CIS019D standard), and the cross-section of the cutting edge has a substantially triangular shape with a flat surface 61 of 50 μm at the tip as shown in Fig. 6. The inside of the cutter roll including the central axis is quenched steel and is fixed to the cemented carbide by shrink fitting. Guide rings were provided at the ends of the roll.

[0034] For the anvil roll, a cylindrical sintered body was obtained using each cermet described in Tables 1 and 2, the SKD11 material as a comparative sample, and cemented carbide (classified as VF-30 according to the CIS019D standard), and it was used. The circumferential surface 34, which is the blade receiving part, was obtained as a smooth surface on a cylindrical grinding machine using a #2000 grinding wheel. The inside of the cylindrical cermet including the central axis of the roll was formed of quenched steel, and the two were fixed by shrink fitting.

[0035] The central axes of the two rolls were inserted and fixed to bearings provided in a frame (not shown) so as to be rotatable. Also, the cutter roll was rotated by a motor (not shown). The guide ring and the circumferential surface of the anvil roll were in contact, and pressure was applied from the bearing part by a cylinder (not shown) in the direction in which the two rolls approached the central axis. As a result, the rotation of the cutter roll was transmitted to the anvil roll through the guide ring, and the anvil roll rotated in the direction opposite to that of the cutter roll. Also, the load required for cutting the workpiece was obtained. The load by the cylinder was set such that the protrusion amount of the cutting edge tip (with the position where the cutting edge tip and the anvil contact in the unpressurized state as the zero point, and the direction away from it represented as -(μm) and the interfering direction as +(μm)) was +5 μm. The cylinder load at this time was 400 kgf.

[0036] In this state, the rotation of both rolls was set to a peripheral speed of 20 m / min and continuously rotated for 5 hours, and then the location where the cutting edge tip contacted the anvil roll circumferential surface was observed.

[0037] First, it was observed whether there was no fine (or more) peeling on the surface. As a result of the observation, fine peeling was seen in Comparative Examples 4, 5, and 13, and no peeling was seen in the other samples. Comparative Example 4 does not contain W, and the strength of the grain boundaries of the cermet structure is not sufficient, and it is considered that fine peeling occurred. Fig. 9 shows a photograph of the anvil roll circumferential surface where wear spread starting from a large number of peeling points. Comparative Examples 5 and 13 do not contain a sufficient amount of Mo, and the wettability between the core phase, rim phase, and metal phase (Co phase) is not sufficient, and it is considered that the structure is vulnerable to impact.

[0038] Regarding Examples 1 to 5, Comparative Examples 1 to 3, Comparative Examples 6 to 12, Comparative Example 14, and Comparative Example 15 where no peeling occurred in the peeling observation, the wear amount was continuously evaluated. The evaluation was performed by measuring, using a laser microscope, how much the contacted part had worn compared to the part on the anvil roll circumferential surface where the cutting edge tip did not contact as a reference. As shown in Fig. 7, the measurement was made with the depth of the deepest part from the circumferential surface 34 (the unworn part) as the measured value. First, a cemented carbide, which is a comparative sample, was measured, and the result was an average wear depth of 1.2 μm. Also, as shown in Fig. 8, the wear morphology of the cemented carbide was such that there were scattered slightly deeper worn parts (white parts) in the part where the cutting edge tip contacted (the blackish banded part). Based on this depth, Equivalent to or more than cemented carbide: wear depth ~1.4 μm or less Slightly inferior to cemented carbide: Wear depth is more than 1.4 μm and 2.4 μm or less Inferior to cemented carbide C: Wear depth is more than 2.4 μm It was evaluated in three stages as follows.

[0039] For Examples 1 to 5, the wear depth (A) was equal to or better than that of cemented carbide. In particular, for Example 1, the wear depth was about 10% smaller than that of cemented carbide. As shown in Fig. 10, the wear morphology was almost the same as that of cemented carbide, and the area of the white part was also equal to or less than that of cemented carbide. Also, the specific gravity of the cermet in any of the examples was 8 or less. For Examples 2 to 5, the wear depth was also almost the same as that of cemented carbide.

[0040] In Comparative Examples 3 and 6, since the amount of W was small, the strength of the grain boundaries of the cermet structure was not sufficient, and it is considered that the wear increased (B).

[0041] Comparative Examples 7 to 11 are samples in which part or all of Co was replaced with Ni. Ni tended to be inferior in hardness and wear resistance compared to Co. Ni may be used as the metal phase, but it is necessary to contain a certain amount or more of Co. When the amount of Co is small, all of these samples were slightly inferior in wear resistance compared to cemented carbide (B).

[0042] In Comparative Examples 1, 2, 12, and 14, the wear depth was slightly inferior to that of cemented carbide (B). These were all samples with a lower amount of Mo than in the examples. Although the hardness was equivalent to that of the examples, it was considered that due to the low amount of Mo, they were in a form that was prone to wear under intermittent loads. Comparative Example 15 is a sample that does not contain Mo, and the wear depth was inferior to that of cemented carbide (C). In Comparative Example 3, W and Mo were interchanged, but the wear depth was clearly inferior. It was found that sufficient wear resistance cannot be obtained if neither W nor Mo is in a sufficient amount (B).

Explanation of symbols

[0043] 1 Rotary cutter 2 Cutter Roll 21 Cutting Edge 22 Guide Ring 23, 33 Central Axis 24, 34 Circumferential Surface 3 Anvil Roll 31 Cylindrical Cemented Carbide (Cutting Edge Receiver) 61 Flat Part at the Tip of the Cutting Edge 7 Wear Part 71 Wear Depth 8 Cemented Carbide Structure 81 Core Phase 82 Rim Phase 83 Metal Phase A Strip-shaped Workpiece to be Cut

Claims

1. It has a circumferential surface which is a smooth blade receiving part in the circumferential direction of the roll, At least the circumferential surface is made of a sintered body of cermet, The cermet has a mass ratio of elements as follows: Ti (titanium) 20 - 45% Mo (molybdenum) 10 - 40% W (tungsten) 10 - 35% C (carbon) 5 - 15% Co (cobalt) 10 - 40% Co + Ni (nickel) 15 - 40% Using powders arbitrarily selected from Ti or Ti compounds, Mo or Mo compounds, W or W compounds, Co or Co compounds, Ni or Ni compounds, and carbon as raw materials so that the ratio becomes: A step of mixing them wet or dry to obtain a mixed powder, A step of press - molding the mixed powder at a pressure of 50 - 300 MPa to obtain a pressed body, Obtained through a step of sintering the pressed body at 1300 - 1700 °C in an atmosphere of any one of vacuum, reduction, inert gas, hydrogen, or nitrogen, having a core phase mainly composed of Ti(C, N), a rim phase mainly composed of (Ti, Mo, W)(C, N) existing so as to cover the periphery of the core phase, and a metal phase, and being a cermet in which the average particle size of the hard phase composed of the core phase and the rim phase in cross - sectional microstructure observation is less than 3 μm Anvil roll.

2. A cutter roll having a cutting blade, and It has a circumferential surface which is a smooth blade receiving part in the circumferential direction of the roll, and at least the circumferential surface is made of a sintered body of cermet, The cermet has a mass ratio of elements as follows: Ti (titanium) 20 - 45% Mo (molybdenum) 10 - 40% W (tungsten) 10 - 35% C (carbon) 5 - 15% Co (cobalt) 10 - 40% Co + Ni (nickel) 15 to 40% Using powders arbitrarily selected from Ti or Ti compounds, Mo or Mo compounds, W or W compounds, Co or Co compounds, Ni or Ni compounds, and carbon as raw materials, Mixing them wet or dry to obtain a mixed powder, Pressing the mixed powder at a pressure of 50 to 300 MPa to obtain a pressed body, Obtained through the step of sintering the pressed body at 1300 to 1700 °C in any atmosphere of vacuum, reduction, inert gas, hydrogen, or nitrogen, having a core phase mainly composed of Ti(C,N), existing so as to cover the periphery of the core phase, a rim phase mainly composed of (Ti,Mo,W)(C,N), and a metal phase, and being a cermet in which the average particle size of the hard phase composed of the core phase and the rim phase in cross-sectional microstructure observation is less than 3 μm, and having an anvil roll, A rotary cutter that cuts a workpiece, which is an object to be cut sandwiched between the cutting edge of the cutter roll and the circumferential surface of the anvil roll, into a desired cutting edge pattern by the rotational movement of the cutter roll and the anvil roll.

3. The rotary cutter according to claim 2, wherein the cutting edge of the cutter roll is made of cemented carbide.

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