Rotary components

Abstract

The present rotating component has a composite structure with a metal matrix and a multitude of ceramic particles dispersed in the metal matrix, and has an elastic modulus of 120 GPa or more.

Description

Technical field

[0001] The present disclosure relates to a rotating component. The present disclosure claims priority from Japanese application no. 2023-116006, filed on July 14, 2023, the entire contents of which are hereby incorporated by reference. State of the art

[0002] Machining devices are often equipped with a rotating component that is set in rotation during use. Patent literature 1 discloses a cutting body holding a cutting tip as such a rotating component. Patent literature 2 further discloses a flange holding a blade as such a rotating component. List of cited writings Patent literature PTL 1: Unexamined Japanese patent application disclosure no. 2012-86338 PTL 2: Unexamined Japanese patent application disclosure no. 2022-112635 Overview of the invention

[0003] A rotational component of the present disclosure has a composite structure with a metal matrix or metal matrix and a plurality of ceramic particles dispersed in the metal matrix, and has an elastic modulus of 120 GPa or more. Brief description of drawings [ Fig. 1] Fig. Figure 1 is a schematic representation showing an example of a rotary component according to one embodiment. [ Fig. 2A] Fig. 2A is an enlarged schematic representation of a cross-section of the in Fig. 1 depicted rotating component. [ Fig. 2B] Fig. 2B is a micrograph of a cross-section of dee in Fig. 1 depicted rotating component. [ Fig. 3] Fig. Figure 3 is a schematic representation of a cutting device described in APPLICATION EXAMPLE 1. [ Fig. 4] Fig. Figure 4 is a perspective partial elevation view of the building. Fig. 3 cutting device shown. [ Fig. 5] Fig. 5 is a partial sectional view of the Fig. 3 cutting device shown. [ Fig. 6] Fig. Figure 6 is an enlarged view of a section in Fig. 5, in which the blade is held. [ Fig. 7] Fig. Figure 7 is a schematic perspective view of a gear described in APPLICATION EXAMPLE 2. [ Fig. 8] Fig. Figure 8 is a schematic perspective elevation view of a motor described in APPLICATION EXAMPLE 3. [ Fig. 9] Fig. Figure 9 is a schematic perspective view of a cutting body described in APPLICATION EXAMPLE 4. [ Fig. 10] Fig.Figure 10 is a schematic view showing a test piece used in a tensile test described in the TEST EXAMPLES. [ Fig. 11] Fig. Figure 11 is a schematic view showing a test device used in a wear resistance test described in the TEST EXAMPLES. Detailed description [Problems to be solved by the present disclosure]

[0004] At high rotational speeds, a rotating component can be deformed by centrifugal force. Thin, plate-like rotating components are particularly susceptible to deformation. For example, if a rotating component holds a machining tool in a machining fixture, deformation of the component can reduce machining accuracy. Furthermore, a rotating component with a large mass tends to be subjected to high centrifugal force and is likely to deform to a greater extent. One of the objectives of this disclosure is to provide a rotating component that is resistant to deformation during rotation. [Beneficial effects of the present disclosure]

[0005] A rotational component of the present disclosure is resistant to deformation during rotation. [Description of embodiments of the present disclosure]

[0006] First, embodiments of the present disclosure will be described one after the other.

[0007] <1> A rotating component of the present disclosure has a composite structure with a metal matrix or metal matrix and a plurality of ceramic particles dispersed in the metal matrix, and has an elastic modulus of 120 GPa or more.

[0008] Structural elements with a composite structure in which ceramic particles are dispersed in a metal matrix are known as metal matrix composites (hereinafter referred to as MMC). Structural elements made of MMC are lighter than structural elements made of metal alone. Therefore, the rotating component of the present disclosure, which is constructed of MMC, is subject to a lower centrifugal force than a rotating component made of metal alone. Therefore, it is unlikely that the rotating component of the present disclosure will deform, even if a centrifugal force acts on it during rotation.

[0009] The rotational component of the present disclosure has a modulus of elasticity of 120 GPa or more. The modulus of elasticity is also referred to as the longitudinal modulus of elasticity. It is determined from the degree of strain (deformation) under tension or compression in a direction. The modulus of elasticity of a rotational component is an index of its resistance to deformation. Rotational components with a modulus of elasticity of 120 GPa or more exhibit minimal deformation, even when a centrifugal force acts upon them during rotation. The rotational component of the present disclosure is resistant to deformation, including deflection, at the time of rotation.

[0010] <2> At the in <1> The specific gravity of the described rotating component can be 5 or less.

[0011] Specific gravity is the density of the oscillatory component divided by the density of water. Specific gravity is a dimensionless number. Since the density of water is 1 g / cm³ 3 The density of the rotational component is 5 g / cm³. 3 or less. Such a rotating component is light and subject to a low centrifugal force when the rotating component is set in rotation.

[0012] <3> In the <1> or <2> The described rotating component may contain a titanium-containing alloy in the metal matrix, and the ceramic particles may contain a titanium-containing ceramic.

[0013] The in <3> The described turned component is lightweight and has a high modulus of elasticity. Furthermore, the turned component exhibits excellent mechanical properties, such as hardness and wear resistance.

[0014] The titanium-containing alloy (Ti) is, for example, 64Ti, which contains titanium, aluminum (Al), and vanadium (V). 64Ti is a titanium alloy containing 6% aluminum and 4% vanadium by mass, based on the total alloy, which is assumed to be 100% by mass. 64Ti is lightweight and characterized by its strength. Titanium-containing ceramics include, for example, titanium boride.

[0015] <4> In the <3> The described rotational component can have a volume ratio of 5 vol.% to 35 vol.%, based on the total volume of the metal matrix and the ceramic particles, i.e., based on 100 vol.%.

[0016] In the machined component with a composite structure in which titanium-containing ceramic particles are dispersed in a titanium-containing alloy, the ceramic particles effectively improve the component's modulus of elasticity when the volume ratio of the ceramic particles is 5 vol.% or more. When the volume ratio of the ceramic particles in the machined component is 35 vol.% or less, the component achieves a high modulus of elasticity and excellent impact strength.

[0017] <5> The in <1> until <4> The described rotary component has a holding element designed to hold a rotating tool.

[0018] Since the holding element is constructed from a rotating component that is torsionally rigid during rotation, the holding element can hold a rotating tool in such a way that the rotating tool maintains a predetermined machining accuracy over a long period of time. The rotating tool is, for example, a disc-shaped blade, as described in later embodiments. The rotating tool can, for example, be a cutting tip.

[0019] <6> In the <5> The described rotating component can be a blade with a ring-shaped form, and the holding element can have a first element and a second element between which the blade is clamped.

[0020] Since the first and second elements are constructed from rotating components that are resistant to deformation during rotation, they can clamp the blade between them, ensuring a stable path of rotation. This results in a smaller cutting edge required when cutting a workpiece. Furthermore, the reduced blade vibration decreases the likelihood of intermittent shocks impacting the workpiece, leading to less stress on parts of the workpiece not directly involved in the cutting process.

[0021] <7> In the <1> until <4> The described rotating component can be a gear, a motor rotor body, or a cutting body designed to hold a cutting tool.

[0022] Gears, motor rotor bodies, and cutting elements must maintain a specified dimensional accuracy during rotation. Rotating components with a modulus of elasticity of 120 GPa or more can meet the above requirement and are therefore suitable for use as gears, motor bodies, and cutting elements. [Details of embodiments of the present disclosure]

[0023] The following are specific examples of the rotating components of this disclosure, illustrated with reference to the drawings. Identical numbers in the drawings denote identical or equivalent features. The component sizes shown in the drawings serve to clarify the explanations and do not necessarily represent the actual dimensions. The present invention is not limited to the examples described below, but is defined by the claims and includes all modifications that fall within the scope and meaning of the claims.

[0024] Fig.Figure 1 shows an example of a rotary component 1, or a rotating part, according to one embodiment. The rotary component 1 is attached to a device that sets the rotary component 1 in rotation and is rotated during operation about the axis of rotation 1S indicated by the dashed line. The rotary component 1 has a shape, structure, and size suitable for rotary operation.

[0025] The shape of the rotating component 1 is not particularly restricted, as long as its center of gravity lies on the axis of rotation 1S. For example, the rotating component 1 can have a disc shape or a column shape. The disc-shaped or column-shaped rotating component 1 can have a blind hole that accommodates a shaft section of a spindle or the like for rotating the rotating component 1. Alternatively, the rotating component 1 can have a ring or cylinder shape with a through hole into which a shaft section of a spindle or the like is fitted for rotating the rotating component 1. Furthermore, the rotating component 1 can alternatively be polygonal, for example triangular, or wave-shaped like a gear when viewed in the direction along the axis of rotation 1S. The in Fig. The rotating component 1 shown is a ring-shaped plate with a through-hole 1h.

[0026] The turning component 1 is made from a sintered body. The turning component 1 has a Fig. The composite structure 10 shown in Figure 2A comprises a metal matrix or metal matrix 11 and a multitude of ceramic particles 12 dispersed in the metal matrix 11. A composite structure 10 with such a structure is referred to as a metal matrix composite (hereinafter MMC).

[0027] For example, metal matrix 11 is a titanium alloy, an aluminum alloy, or stainless steel. Examples of titanium alloys include Ti-5Al-2.5Sn, Ti-6Al-4V, Ti-3Al-2.5V, Ti-6Al-4V-2Sn, Ti-15V-3Cr-3Sn-3Al, Ti-13V-11Cr-3Al, or Ti-3Al-8V-6Cr-4Mo-4Zr. Sn stands for tin, Cr for chromium, Mo for molybdenum, and Zr for zirconium. The numbers in the compositions of the titanium alloys described above are the mass ratios of the respective elements, based on the mass of the titanium alloy, which is assumed to be 100% by mass. In particular, Ti-6Al-4V, also known as 64Ti, exhibits excellent strength.

[0028] For example, the ceramic particles 12 are a boride containing a metal derived from the metal matrix 11. If the metal matrix 11 is a titanium alloy, the ceramic is, for example, titanium boride (TiB).

[0029] The rotating component 1, which is composed of MMC containing a variety of ceramic particles 12, is lighter than a rotating component made entirely of metal. Therefore, the rotating component 1 is subjected to only a small centrifugal force when rotated at high speed. Consequently, it is unlikely that the rotating component 1 will deform, even when subjected to centrifugal force during rotation. The ceramic particles 12 contained in the rotating component 1 also contribute to increasing its modulus of elasticity.

[0030] The elastic modulus of the rotating component 1 is 120 GPa or more. A rotating component 1 with an elastic modulus of 120 GPa or more is resistant to deformation even when a centrifugal force acts during rotation. The elastic modulus is determined by a tensile test described later. For example, the elastic modulus of the rotating component 1 can be 125 GPa or more, 130 GPa or more, or even 140 GPa or more. From the perspective of the performance of the rotating component 1, which is achieved through a high elastic modulus, there is no upper limit for its elastic modulus. However, from the perspective of ease of manufacturing, the upper limit for the elastic modulus of the rotating component 1 is 250 GPa.

[0031] For example, the tensile strength of the turning component 1 can be 1000 MPa or more. For turning component 1 with a tensile strength of 1000 MPa or more, there is only a low probability of irreversible deformation during high-speed rotation. For example, the tensile strength can be 1050 MPa or more, or 1100 MPa or more. From the perspective of the effect of turning component 1, which is achieved through high tensile strength, there is no upper limit for the tensile strength of turning component 1. From the perspective of ease of manufacturing turning component 1, the upper limit for the tensile strength of turning component 1 is 2000 MPa.

[0032] For example, the specific gravity of rotational component 1 is 5 or less. The specific gravity of rotational component 1 is the density of rotational component 1 divided by the density of water. For example, the density of rotational component 1 is determined using Archimedes' method. The unit of density is g / cm³. 3 The density of the rotational component 1 varies depending on the composition of the composite structure 10. A rotational component 1 with a specific gravity of 5 or less is relatively light, and its rotation generates a relatively small centrifugal force acting upon it. The smaller the specific gravity of the rotational component 1, the smaller the centrifugal force. For example, the specific gravity of the rotational component 1 can be 4.9 or less, or 4.7 or less.

[0033] If the total volume of the metal matrix 11 and the ceramic particles 12 in the rotational component 1 is assumed to be 100 vol.%, the volume ratio VR of the ceramic particles 12 is, for example, 5 vol.% to 35 vol.%. The volume ratio is the percentage of the ratio V1 / V0 of the volume V1 of the ceramic particles 12 to the total volume V0 of the metal matrix 11 and the ceramic particles 12.

[0034] If the volume ratio VR is 5 vol.% or more, the addition of the ceramic particles 12 leads to a significant improvement in the elastic modulus of the rotating component 1. If the volume ratio VR is 35 vol.% or less, the rotating component 1 achieves a high elastic modulus and excellent impact strength. For example, the volume ratio VR can be 5 vol.% to 30 vol.%, 7 vol.% to 25 vol.%, or 9 vol.% to 20 vol.%.

[0035] For example, the volume ratio VR is determined by image analysis of a micrograph of a cross-section of the Fig.The rotational component 1 shown in Figure 2B is determined. In particular, an observation field of a cross-section with a predetermined area is analyzed using image analysis software (ImageJ, a publicly available image analysis software). During the image analysis, the metal matrix 11 and the ceramic particles 12 are extracted from the observation field. Next, the grayscale image is binarized to calculate the area of ​​the metal matrix 11 and the area of ​​the ceramic particles 12. In the grayscale image, which consists of 256 grayscale levels, light grayscale levels from level 0 to level 120 are assigned to the metal matrix, and dark grayscale levels from level 121 to level 256 are assigned to the ceramic particles. Voids are not included in the area of ​​the metal matrix 11.The sum of the area of ​​the metal matrix 11 and the area of ​​the ceramic particles 12 is assumed to be 100 area percent, and the area ratio of the ceramic particles 12 to the total area of ​​the metal matrix 11 and the ceramic particles 12 is calculated accordingly. In the present disclosure, the area ratio of the ceramic particles 12 determined from a cross-section of the rotating component 1 is assumed to be the volume ratio VR of the ceramic particles 12 in the rotating component 1.

[0036] As an example, a turned component 1, which is built from a titanium-based sintered body, is manufactured by a process described below. In the turned component 1, which is built from a titanium-based sintered body, the metal matrix 11 comprises a titanium alloy, and the ceramic particles 12 contain a titanium-containing ceramic. The manufacturing process comprises the following steps. • Step of providing a raw material powder • Step of mixing the raw material powder with a lubricant to produce a mixed powder • Step of pressure forming the mixed powder • Step of cutting the blank • Step of removing the lubricant • Step of sintering the blank • Step of compressing the titanium-based sintered body by hot isostatic pressing • Step of completing the sintered body

[0037] The steps are described in detail below. <<Schritt des Bereitstellens eines Rohmaterialpulvers> >

[0038] The raw material powder contains titanium. The raw material powder can be pure titanium or a titanium alloy powder. It can be composed of pure titanium and a powder containing an element that can alloy with titanium. For example, the element other than titanium in the raw material powder is Al, V, Sn, Cr, Mo, or Zr. The element other than titanium is selected appropriately according to the composition of the metal matrix 11 to be produced. A specific example of the raw material powder includes a Ti powder composed of pure titanium and an Al-V powder composed of an aluminum-vanadium compound.The raw material powder, which contains a Ti powder and an Al-V powder, yields a metal matrix 11 composed of a Ti-6Al-4V alloy.

[0039] The raw material powder also contains a ceramic powder. This ceramic powder is, for example, titanium diboride (TiB2). Therefore, due to the raw material powder containing the ceramic powder, the manufactured turning component 1 is composed of MMC.

[0040] For example, the particle size of the raw material powder ranges from 0.1 µm to 100 µm. The particle size of the raw material powder can be measured using a particle size distribution analyzer. If the raw material powder to be molded has a fine particle size, the resulting body tends to trap air in the spaces between the ceramic particles, resulting in a high oxygen concentration. The oxygen contained in the body can impair the mechanical properties of a titanium-based sintered body obtained by sintering the raw material. If the particle size of the raw material powder is 0.1 µm or larger, aggregation during mixing can be suppressed. If the particle size of the raw material powder is 100 µm or smaller, the raw material and the sintered body tend to achieve a high density.For example, the particle size of the raw material powder can range from 0.5 µm to 90 µm. <<Schritt des Mischens des Rohmaterialpulvers mit einem Schmiermittel> >

[0041] The raw material powder and a lubricant can be mixed in any way without restriction. For example, the raw material powder and a lubricant can be mixed using a ball mill, an attritor / friction mill, or a jet mill. When mixing with a ball mill, attritor, or jet mill, the raw material powder is subjected to a high energy input. The raw material powder and a lubricant can also be mixed using a V-mixer. When mixing with a V-mixer, the raw material powder is subjected to a relatively low energy input.

[0042] For example, the lubricant is stearic acid, zinc stearate, stearamide, or ethylene bisstearamide. Stearic acid, in particular, is suitable for the production of a titanium-based turning component 1, since stearic acid evaporates at a temperature of 270 °C or above.

[0043] Based on the raw material powder, which is assumed to be 100% by mass, the mixing ratio of the lubricant to the raw material powder is, for example, 0.05% to 0.5% by mass. If the lubricant is added in an amount of 0.05% by mass or more, based on 100% by mass of the raw material powder, the blank can be easily cut in the blank cutting step described later. If the amount of lubricant added is 0.5% by mass or less, based on 100% by mass of the raw material powder, the amount of lubricant is not excessive relative to the raw material powder, and the blank tends to achieve a high density. The amount of lubricant added can be 0.2% to 0.5% by mass or 0.3% to 0.4% by mass. <<Schritt des Druckformens des Rohmaterialpulvers> >

[0044] The forming process is carried out, for example, by cold isostatic pressing. The mold temperature ranges from 0 °C to 50 °C. The cold isostatic mold is made of a non-metallic elastic material, such as urethane rubber, an acrylic resin, an acrylic resin containing an elastomer, or a polylactic acid resin. Because the cold isostatic mold is not metal, titanium does not adhere to it. The blank obtained by cold isostatic pressing has a relatively simple shape. For example, the blank is columnar or cylindrical.

[0045] The forming pressure is selected according to the raw material powder and the density of the blank. For example, the forming pressure might be 200 MPa or more. It could also be 350 MPa or more, or 500 MPa or more. The upper limit of the forming pressure depends on the machine's capacity. For example, the upper limit might be 800 MPa. Generally, the higher the forming pressure, the higher the density of the resulting pressed blank. <<Schritt des Schneidens des Rohlings> >

[0046] The blank is cut into a shape closely resembling that of the turned component 1. The cutting is performed, for example, using a lathe or a machining center. The cutting can be continuous with a tool attachment or the like, or intermittent with a rotating tool or the like. Since the blank of this disclosure contains a lubricant, it is unlikely that the cutting tool will be damaged during the cutting process. The low probability of cutting tool damage can minimize the increase in cutting costs associated with tool replacement. Furthermore, a decrease in cutting accuracy is unlikely, and the cut blank achieves improved surface properties.

[0047] The higher the lubricant content in the blank, the less likely it is that the cutting tool will be damaged, and the more easily the blank will achieve improved surface properties. The lubricant content relative to the raw material powder in the blank can be considered equal to the amount of lubricant that is mixed with the raw material powder when the raw material powder and lubricant are mixed together. <<Schritt zum Entfernen des Schmiermittels> >

[0048] In the lubricant removal step, the blank is heat-treated in an inert atmosphere at 400 °C or below. An inert atmosphere could be, for example, nitrogen or argon. In this inert atmosphere, nitriding of the titanium in the blank is unlikely. However, because titanium nitride is brittle, its presence in the blank can degrade the mechanical properties of a titanium-based sintered body obtained by sintering the blank. Titanium nitride inhibits sintering of the blank and can lead to a deterioration of the mechanical properties of the titanium-based sintered body. Since the blank sometimes contains air, even heat-treating the blank in an argon atmosphere can lead to the formation of titanium nitride if the argon atmosphere has a temperature above 400 °C.

[0049] Stearic acid evaporates at 270 °C or above. If the blank contains stearic acid as a lubricant, heat treatment is carried out in an inert atmosphere at, for example, 270 °C to 380 °C. If the temperature of the inert atmosphere is in the range of 270 °C to 380 °C, most of the stearic acid is removed from the blank. By controlling the inert atmosphere to 380 °C or below, the formation of titanium nitride in the blank is effectively suppressed.

[0050] The heat treatment time, during which the blank is held within the aforementioned temperature range, is, for example, 10 minutes to 8 hours. A heat treatment time of 10 minutes or more ensures that the temperature in the center of the blank is sufficiently raised so that the lubricant can be easily removed from the entire blank. A heat treatment time of 8 hours or less avoids excessively extending the time required to produce the titanium-based sintered body. The heat treatment time can range from 3 to 6 hours. After heat treatment, the blank is cooled to room temperature in the furnace. <<Schritt des Sinterns des Rohlings> >

[0051] In the sintering step of the blank, the blank, now free of lubricant, is sintered in a vacuum atmosphere. For example, the atmospheric pressure is 0.1 Pa or less. The temperature of the atmosphere is selected according to the materials of the raw material powder. For example, the temperature of the atmosphere is 1100 °C to 1400 °C.

[0052] For example, the sintering time ranges from 1 hour to 25 hours. A sintering time of 1 hour or more ensures that the entire blank is sufficiently sintered. A sintering time of 25 hours or less prevents an excessive extension of the time required to produce the titanium-based sintered body. The sintering time can range from 8 to 18 hours. The titanium-based sintered body is cooled to room temperature in the furnace.

[0053] Even a vacuum atmosphere contains traces of air. During the sintering of the blank, the nitrogen in the air can react with the titanium contained in the blank. The amount of titanium nitride in the titanium-based sintered body is reduced by embedding the blank in zirconium oxide spheres and additionally placing titanium pieces as getters on the zirconium oxide spheres.

[0054] For example, the relative density of the titanium-based sintered body is 95 vol.% or more. In the present disclosure, relative density is the volume ratio of the solid fraction to the volume of the object being measured. Even if the blanks have the same relative densities before sintering, differences in the blank's production lead to differences in the relative density of the titanium-based sintered bodies. For example, if a blank is sintered from a master alloy powder as the raw material powder, the relative density of the titanium-based sintered body will not be high. Master alloy powder is a powder that has the same composition as the titanium alloy from which the titanium-based sintered body will be composed. If a blank is sintered from a raw material powder that is a mixture of several types of powder, the relative density of the titanium-based sintered body will tend to be high.

[0055] For example, the titanium alloy forming the metal matrix 11 is Ti-5Al-2.5Sn, Ti-6Al-4V, Ti-3Al-2.5V, Ti-6Al-4V-2Sn, Ti-15V-3Cr-3Sn-3Al, Ti-13V-11Cr-3Al, or Ti-3Al-8V-6Cr-4Mo-4Zr. The ceramic particles 12 dispersed in the metal matrix 11 are titanium boride (TiB). Titanium boride is a precipitate originating from titanium diboride (TiB2) that was added to the raw material powder. <<Schritt des Komprimierens des Sinterkörpers auf Titanbasis durch heiß-isostatisches Pressen> >

[0056] The relative density of the titanium-based sintered body is further increased by hot isostatic pressing. The relative density of the titanium-based sintered body to undergo hot isostatic pressing should be 95% or higher. If the relative density of the titanium-based sintered body is less than 95%, increasing the density through hot isostatic pressing is difficult and not always necessary.

[0057] The temperature of hot isostatic pressing is selected according to the composition of the sintered body. For example, the hot isostatic pressing temperature is 800 °C to 1100 °C. The treatment time is typically 30 minutes to 6 hours. A treatment time of 30 minutes or more ensures that the relative density of the sintered body is sufficiently increased. A treatment time of 6 hours or less avoids excessively extending the time required to produce the sintered body. The treatment time can range from 1 hour to 4 hours. The sintered body is cooled to room temperature in the hot isostatic pressing device. For example, the pressure is 150 MPa or more. <<Schritt zum Fertigstellen des Sinterkörpers> >

[0058] In the finishing step, for example, the surface of the titanium-based sintered body is ground. Grinding gives the titanium-based sintered body the desired dimensions and smooths its surface. Furthermore, grinding removes impurities concentrated on the surface of the titanium-based sintered body. These impurities include, for example, titanium oxide, titanium carbide, or titanium nitride. Removing these impurities from the surface of the sintered body improves its mechanical properties. The finished titanium-based sintered body is the turned component 1 of this disclosure. <ANWENDUNGSBEISPIEL 1>

[0059] An exemplary device in which the rotary component 1 is used is described with reference to Fig. 3 to Fig.6 described. Fig. Figure 3 is a schematic perspective view of a cutting device 9, which is an example of a device equipped with the rotary component 1. The cutting device 9 is a device for cutting a wafer 8, on which several integrated circuits are located, into several chips. The cutting device 9 has a rotary mechanism 9M which includes a blade 90 for cutting the wafer 8.

[0060] As in the perspective elevation view of Fig. As shown in Figure 4, the rotary mechanism 9M comprises the blade 90 with an annular shape and a first element 91 and a second element 92 that sandwich-like enclose the blade 90. The first element 91 and the second element 92 are each rotary components 1 with a composite structure 10. The rotary components 1 are retaining elements designed to hold the blade 90, which is a rotary tool. As shown in Fig. As shown in Figure 5, the blade 90 is attached to a shaft section 95S of a spindle 95 by means of a nut 93, while it is positioned between the first element 91 and the second element 92.

[0061] The first element 91 is an approximately cylindrical element with a through bore 91h. The first element 91 has, in the order that it is closest to and opposite the spindle 95: a first cylindrical section 91A, a ring section 91B, and a second cylindrical section 91C. As shown in Fig. As shown in Figure 5, the shaft section 95S of the spindle 95 passes through the through-bore 91h. The end face of the first cylindrical section 91A abuts the spindle 95.

[0062] As seen in the partially enlarged view of Fig. As shown in Figure 6, the ring section 91B has a base section 910 with the through-bore 91h (see Fig.5) and a holding section 915, which is arranged on the outer circumference of the base section 910. In Fig.Figure 6 shows the boundary between the base section 910 and the retaining section 915 virtually represented by the dashed line with two dots. The retaining section 915 is thinner than the base section 910. On the surface of the first element 91, facing the second element 92, a step is formed between the base section 910 and the retaining section 915. The surface of the retaining section 915 facing the second element 92 is a retaining surface 91P, which holds the blade 90, described later. The retaining section 915 becomes thinner as it approaches its outer circumference. The retaining surface 91P is a flat surface perpendicular to the axis of the through-bore 91h. The surface opposite the retaining surface 91P has an inclined plane that becomes increasingly inclined towards the second element 92 as it approaches the outer circumference of the retaining section 915.

[0063] The second element 92 is a roughly ring-shaped element with a through-bore 92h (see Fig. 5) The second cylindrical section 91C of the first element 91 extends through the through-bore 92h. The second element 92 has, in the arrangement closest to and opposite the first element 91, an annular section 92D and a cylindrical section 92E. The annular section 92D has a base section 920 with the through-bore 92h and a retaining section 925, which is arranged on the outer circumference of the base section 920. Fig.Figure 6 shows the boundary between the base section 920 and the retaining section 925 virtually represented by the dashed line with two dots. The retaining section 925 projects towards the first element 91 compared to the base section 920. The outer circumferential section of the ring section 92D projects further towards the first element 91 compared to the other sections except the outer circumferential section. In the outer circumferential section of the ring section 92D, the surface facing the first element 91 is a retaining surface 92P, which holds the blade 90, described later. The retaining surface 92P is a flat surface that is approximately perpendicular to the axis of the through-bore 92h. That is, only the outer circumferential region of the retaining surface 92P is in contact with the blade 90.The surface of the holding section 925 opposite the holding surface 92P has an inclined surface which is increasingly inclined towards the first element 91 as the surface approaches the outer circumference of the holding section 925.

[0064] The blade 90 is a ring-shaped plate. The blade 90 is clamped between the holding surface 91P of the first element 91 and the holding surface 92P of the second element 92.

[0065] The nut 93 is screwed onto the outer circumference of the second cylindrical section 91C of the first element 91. Fig. In section 5, the threads and thread grooves are omitted. Tightening the nut 93 holds the blade 90 firmly between the first element 91 and the second element 92.

[0066] In the cutting device 9 of the application example, the blade 90, the first element 91, and the second element 92 are rotated at very high speed. Since the first element 91 and the second element 92 are rotating components 1 with a composite structure 10, the retaining section 915 of the first element 91 and the retaining section 925 of the second element 92 are resistant to deformation caused by centrifugal force. Thus, the retaining section 915 and the retaining section 925 hold the blade 90 stably, and the blade 90's rotational path is easily stabilized. With a stable rotational path of the blade 90, the kerf width tends to be smaller when cutting the wafer 8. A stable rotational path of the blade 90 reduces the probability of intermittent shocks acting on the wafer 8 and results in less stress on the parts of the wafer 8 that are not at the cutting point.

[0067] The turning component 1 can, for example, be used for the cutting body of the cutting device described in patent literature 1. A cutting body is a roughly columnar element that holds several cutting tips. The cutting tips are arranged at intervals on an outer circumferential section of an end face of the cutting body. If this cutting body is made of MMC with the same or a similar composite structure 10 as the turning component 1, each of the cutting tips has a stable rotational path. This allows the cutting device to achieve improved machining accuracy. <ANWENDUNGSBEISPIEL 2>

[0068] Based on Fig. Section 7 describes an example where the rotary component 1 forms a gear 2. This is shown in Fig. The gear 2 shown in Figure 7 is a helical gear used in a reduction gearbox.

[0069] The intervention accuracy between the in Fig.The relationship between gear 2 shown in Figure 7 and another gear meshing with it has a significant impact on power transmission efficiency and noise generation. In recent years, the demand for improved power transmission efficiency and low noise levels in reduction gearboxes has increased. Gear 2 must not only be manufactured with very high dimensional accuracy but also maintain high dimensional accuracy during operation. Gear 2 with a high modulus of elasticity of 120 GPa or more can meet the aforementioned requirements. <ANWENDUNGSBEISPIEL 3>

[0070] Based on Fig. Section 8 describes an example where the rotational component 1 forms a rotor body 30 of a motor 3. Fig. Figure 8 is a schematic perspective elevation view of engine 3.

[0071] Motor 3 has two stators 31 and 32 and a rotor body 30 located between stator 31 and stator 32. Motor 3 is a so-called double-stator axial gap motor. Motor 3 can also be a single-stator axial gap motor. The stators 31 and 32 have a core 35 and coils 36. The coils 36 are arranged on the outer circumference of teeth 350, which are part of the core 35.

[0072] The rotor body 30 is an annular plate with a through-bore 30h. A shaft (not shown) is arranged in the through-bore 30h. The rotor body 30 has several recesses 30c arranged to surround the through-bore 30h. A magnet 30M is arranged in each recess 30c. The rotor body 30 not only holds the magnets 30M but also plays a role in positioning them.

[0073] When an alternating current is applied to the coils 36 in the motor 3 with the above-mentioned configuration, rotating magnetic fields are generated in the stators 31, 32. The magnets 30M are attracted or repelled by the rotating magnetic fields, causing the rotor body 30 to rotate. The rotor body 30 rotates at a high speed of several tens of thousands of rpm (revolutions per minute). For this reason, the rotor body 30 must be made of a material that is lightweight and very strong. The dimensional accuracy of the rotor body 30 affects the torque of the axial gap motor, the rotational speed of the rotor body 30, and the stability of the rotation of the rotor body 30. The rotor body 30 must maintain its high dimensional accuracy even when rotating. A rotor body 30 with a high modulus of elasticity of 120 GPa or more can meet the above-mentioned requirements. <ANWENDUNGSBEISPIEL 4>

[0074] Based on Fig.Section 9 describes an example where the turning component 1 forms a milling body 4. The one in Fig. The milling body 4 shown in Figure 9 is a device that holds cutting tips 40 for machining a workpiece by milling or the like. The milling body 4 is an approximately cylindrical element with a through bore 4h. Recesses for holding the cutting tips 40 are arranged on the outer circumferential surface of the milling body 4. The cutting tips 40 are fastened to the milling body 4 with a screw.

[0075] When the cutting body 4 is rotated at high speed around the axis of rotation 1S, any deformation poses a risk of deteriorating the surface properties, including the smoothness of the machined surface. The milling body 4 must be resistant to deformation during rotation. A milling body 4 with a high modulus of elasticity of 120 GPa or more can meet the aforementioned requirement. <testbeispiele><<TESTBEISPlEL 1> >

[0076] In TEST EXAMPLE 1, the mechanical properties of materials used to manufacture turned components were investigated. The mechanical properties of a turned component correspond to the mechanical properties of the material used to manufacture that component. The mechanical properties investigated were density, modulus of elasticity, tensile strength, wear resistance, and Rockwell hardness. The samples provided in TEST EXAMPLE 1 were as follows: [Sample No. 100]

[0077] Specimen No. 100 is a cast ingot made of a 64-titanium alloy. The cast ingot of Specimen No. 100 is produced by pouring a melt of a 64-titanium alloy into a mold. In the table described later, the 64-titanium alloy is referred to as "64Ti". [Sample No. 1]

[0078] Sample No. 1 is an MMC with a composite structure 10, which is in Fig. 2A and Fig. Figure 2B shows the metal matrix 11 in this MMC, which is composed of a 64-titanium alloy, and the ceramic particles 12 are made of TiB. In the table described later, this MMC is referred to as "64Ti-MMC".

[0079] For the preparation of sample No. 1, a first powder made of an Al-V compound, a second powder made of pure titanium, and a ceramic powder made of TiB2 were provided. The particle size of the first powder was 20 µm to 90 µm. The particle size of the second powder was 20 µm to 45 µm. The particle size of the ceramic powder was 0.7 µm to 10 µm.

[0080] The first powder, the second powder, the ceramic powder, and a lubricant were mixed together to obtain a raw material powder. The ball mill hopper was made of tungsten carbide. The grinding balls placed in the ball mill hopper were also made of tungsten carbide. The grinding balls had a diameter of 10 mm, and there were 50 of them. The mixing conditions were 300 rpm for 1 hour.

[0081] The raw material powder was cold-isostatically pressed into a cylindrical blank. The forming pressure was 390 MPa and the holding time was 30 seconds.

[0082] The samples produced in TEST EXAMPLE serve to provide data on the mechanical properties. Therefore, the blank was heat-treated without cutting, which removed the stearic acid, a lubricant, from the blank. Stearic acid facilitates cutting the blank. The atmosphere in the inert furnace was nitrogen, the heat treatment temperature was 380 °C, and the heat treatment time was 4 hours. The heating rate in the inert furnace was 5 °C / min.

[0083] The blank, freed from lubricant, was placed in a sintering furnace and sintered into a sintered body. The atmosphere in the sintering furnace was a vacuum at 0.1 Pa or less, the sintering temperature was 1300 °C, and the sintering time was 12 hours. The heating rate in the sintering furnace was 6.7 °C / min up to 1290 °C and 1 °C / min from 1290 °C to 1300 °C. The sintered body was an MMC with a composite structure 10, comprising a metal matrix 11 with titanium and ceramic particles 12 dispersed in the metal matrix 11. The composition of the metal matrix 11 was a 64-titanium alloy. The composition of the ceramic particles 12, derived from TiB₂, was titanium boride (TiB₂). [Measurement of relative density]

[0084] Relative density is the ratio of the volume of the solid component to the volume of the object being measured. The unit of relative density is vol.%. The relative density was measured using the Archimedes method.

[0085] The relative density of sample no. 100 was almost 100 vol.%. Sample no. 100, which consisted of a single cast block, is considered to be virtually free of voids.

[0086] For sample no. 1, the relative density of the blank before sintering and the relative density of the titanium-based sintered body after sintering were measured. The relative density of the blank was at least 75 vol%, more precisely 80 vol%. The relative density of the titanium-based sintered body was at least 95 vol%, more precisely 97 vol%. It was found that the relative density of the titanium-based sintered body was at least 15 vol% higher, and in particular 17 vol% higher, than the relative density of the blank before sintering. [Tensile test]

[0087] To determine the modulus of elasticity and the tensile strength of each sample, a test piece was produced from the sample and subjected to a tensile test. A universal tensile testing machine from TOKYO KOKI TESTING MACHINE CO., LTD. was used. The sample was produced by machining the cylindrical blank. Fig. Figure 10 is a schematic representation of the shape of specimen 5. The specimen 5 has a first gripping section 51, a second gripping section 52, and an intermediate section 50. The diameter of the intermediate section 50 was 6.35 mm (millimeters), and the distance d between a first measuring mark 50A and a second measuring mark 50B, provided in the intermediate section 50, was 25.4 mm. The temperature during the tensile test was room temperature. The strain rate until reaching a yield strength of 0.2% was 1.2 mm / min, and the strain rate after reaching a yield strength of 0.2% was 12.8 mm / min. Based on the stress-strain curve obtained from the tensile test, the modulus of elasticity and the tensile strength of each specimen were determined. The unit of elasticity is GPa, and the unit of tensile strength is MPa. The test results are described in Table 1. [Hardness]

[0088] The Rockwell hardness of each sample was measured. The ADR-A Rockwell hardness tester from Akashi Seisakusho Co., Ltd. was used. The measurement was performed using the C scale and a spherical-conical diamond indenter. The unit of Rockwell hardness is HRC. The Rockwell hardness measurement results are described in Table 1. [Wear resistance test]

[0089] A test piece was produced from each sample and subjected to a wear resistance test. The Bruker Japan KK UMT TriboLab wear testing device was used. The test piece was produced by machining the cylindrical blank. Fig. Figure 11 is a schematic representation of the test apparatus 7 for the wear resistance test. The shape of the test specimen 6 in this test is cylindrical. In the test, the circumferential surface of the test specimen 6 was pressed against a rotating disk 70, and the degree of wear on the circumferential surface of the test specimen 6 was measured. The material of the disk 70 was SUJ2 according to JIS G 4805. The rotational speed of the disk 70 was 600 rpm. The test specimen 6 was pressed against the disk 70 with a load of 30 N. The sliding length for the test specimen 6 was 60 m. The sliding length is the distance by which the disk 70, which is in contact with the test specimen 6, moves relative to the test specimen 6.

[0090] The surface of test piece 6, which had been in contact with disc 70, was examined under a microscope, and the average length of the wear marks was measured. The length of a wear mark is the length along the direction of rotation of disc 70 and is given in the unit µm. In this example, the average length of the wear marks is the average of the lengths of the wear marks at three different locations. The average length of the wear marks is described in Table 1. [Table 1] Sample number 100 1 material 64Ti 64Ti-MMC Modulus of elasticity (GPa) 110 140 Tensile strength (MPa) 980 1100 Wear amount (µm) 1050 220 Rockwell hardness (HRC) 30 37

[0091] The results in Table 1 show that sample No. 1, composed of MMC with a 64Ti metal matrix 11, outperforms sample No. 100, which consists of a 64Ti cast block, in all mechanical properties. A turning component 1 made from sample No. 1, which has a high modulus of elasticity and high tensile strength, is less susceptible to deformation due to centrifugal force and returns to its original shape more readily when the centrifugal force disappears than a turning component made from sample No. 100.

[0092] Regarding wear resistance, the wear of sample No. 1 was approximately 1 / 5 of the wear of sample No. 100. Therefore, if a rotating component 1 made from sample No. 1 holds a rotating tool, the surface of the rotating component 1 that is in contact with the rotating tool is wear-resistant. <<TESTVERFAHREN 2> >

[0093] In TEST PROCEDURE 2, the relationship between the volume ratio of the ceramic particles in a composite structure of a rotating component and the specific weight and the modulus of elasticity was investigated.

[0094] Sample No. 1 in TEST EXAMPLE 2 is identical to Sample No. 1 in TEST EXAMPLE 1. The volume fraction VR of the ceramic particles 12 in Sample No. 1 was 10 vol.%. The volume fractions VR of the ceramic particles 12 in Samples No. 2, No. 3, No. 4, and No. 5 were 5 vol.%, 16.7 vol.%, 25 vol.%, and 33.3 vol.%, respectively. The volume fractions VR were determined by image analysis of a cross-section of the sample as described in the embodiments.

[0095] The specific gravity and modulus of elasticity were measured for samples No. 1 to No. 5. The specific gravity was determined according to the procedure described in the embodiments. The modulus of elasticity was measured in the same way as in TEST EXAMPLE 1. The measurement results are described in Table 2. [Table 2] Sample number 1 2 3 4 5 Volume ratio (Vol.-%) of ceramic particles 10 5 16,7 25 33,3 Specific gravity 4,4 4,4 4,4 4,4 4,4 Modulus of elasticity (GPa) 140 124 159 178 197

[0096] As described in Table 2, it has been shown that the elastic modulus of the rotational component 1 is higher with increasing volume fraction of the ceramic particles 12 contained in the rotational component 1.

[0097] The specific gravities of the rotating component 1 remained almost unchanged even when the volume fraction of the ceramic particles 12 contained in the rotating component 1 was increased. This is because the specific gravity of TiB is only slightly lower than that of titanium 64. The specific gravities of samples No. 1 to No. 5 are identical to one decimal place, but in reality, the specific gravities decrease with increasing volume fraction of the ceramic particles 12. List of reference symbols 1 Rotating component or rotating part 1h through drilling 1S Rotary Axis 10 Composite structure, 11 Metal matrix, 12 ceramic particles 2 gear 3 Engine 30 rotor bodies, 30c recess, 30h through-hole drilling, 30M Magnet 31, 32 stators 35 core, 36 coils, 350 teeth 4 cutting bodies 40 cutting tip 5 test pieces 50 Intermediate section 50A first measurement mark, 50B second measuring mark 51 first grip section, 52 second grip section 6 test pieces 7 Testing device 70 disc 8 wafers 9 Cutting device 9M rotating mechanism 90 blade 91 first element 91h through hole, 91P holding surface 91A first cylindrical section, 91B Ring section, 91C second cylindrical section 910 Base section, 915 Stop section, 92 second element 92h through hole, 92P holding surface 92D ring section, 92E cylindrical section 920 base section, 925 Stop section, 93 Mother 95 spindle, 95S wave section d measuring distance QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] JP 2023

[0001] JP 116006

[0001] < / testbeispiele>

Claims

[1] Rotational component comprising a composite structure with a metal matrix and a plurality of ceramic particles dispersed in the metal matrix, wherein the rotational component has an elastic modulus of 120 GPa or more. [2] Rotating component according to claim 1, wherein the specific gravity is 5 or less. [3] Rotary component according to claim 1 or 2, wherein the metal matrix comprises a titanium-containing alloy and the ceramic particles comprise a titanium-containing ceramic. [4] Rotary component according to any one of claims 1 to 3, wherein the volume ratio of the ceramic particles is 5 vol% to 35 vol%, based on the total volume of the metal matrix and the ceramic particles assumed to be 100 vol%. [5] Rotary component according to any one of claims 1 to 4, wherein the rotary component has a holding element designed to hold a rotating tool. [6] Rotating component according to claim 5, wherein the rotating tool is a blade with an annular shape and the retaining element comprises a first element and a second element, between which the blade is arranged. [7] Rotating component according to any one of claims 1 to 4, wherein the rotating component is a gear, a motor rotor body or a cutting body designed to hold a cutting tool.

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