JP2019116914A - Slide member and use thereof - Google Patents

Abstract

To provide a slide member facilitating enlargement of a shaft/bearing structure, and having improved mechanical characteristics of a base material for fixing sliding contact particles.SOLUTION: A slide member includes a slide member substrate (10a) and a composite material (12) fixed to a surface of a slide member base part. The composite material (12) is a sintered body comprising a specific amount of sliding contact particles (12b) slidably contacting with a member to be slid, and a composite base material (12a) fixing the sliding contact particles (12b) to the slide member base part. The sliding contact particle (12b) projects from a surface of the composite base material (12a).SELECTED DRAWING: Figure 1

Description

  The present invention relates to a sliding member and its use, particularly to a sliding member that can be suitably used for a pump.

  As a type of drainage pump, a leading standby pump is known. For example, in response to a rapid increase in the amount of water such as guerrilla heavy rain, the preceding standby operation pump can perform full speed operation (advanced standby operation) in an anhydrous state in advance and can perform drainage in a mixed state of air and water. It has become. For example, Patent Document 1 discloses a sliding member that can be applied to such a prior standby operation pump.

  Patent Document 1 discloses a pump shaft / bearing structure provided with a sliding member base and sliding contact particles. The sliding contact particles are scattered and fixed on the surface of the sliding member base, and are projected from the surface of the sliding member base, and are described as being in sliding contact with the sliding member.

Unexamined-Japanese-Patent No. 2016-211727 (December 15, 2016 publication)

  However, in the prior art as described above, after the sliding contact particles with a particle diameter of several tens of μm to several hundreds of μm are fixed to the sliding member base, the shaft / bearing structure is manufactured by processing. There has been concern that the manufacturing facilities will be enlarged with the increase in size. In addition, since the load applied to the sliding member is increased, there is a problem in mechanical characteristics of the base material for fixing the sliding contact particles.

  The present invention has been made in view of the above problems, and the object is to cope with the enlargement of the shaft / bearing structure, and further to improve the mechanical characteristics of the base material for fixing the sliding contact particles. To provide.

As a result of intensive studies to achieve the above object, the inventors of the present invention, as a result of sliding contact particles slidingly contacting the sliding member, and a composite base material for fixing the sliding particles to the sliding member base By fixing the composite material including the above to the sliding member base, it can be easily coped with the enlargement of the shaft and bearing structure, and further, it is found that the mechanical characteristics of the base for fixing the sliding contact particles are improved. We came to complete the invention. That is, the present invention includes the following inventions.
[1] A sliding member which slides relative to a sliding member, which is a sliding member,
The sliding member is
A sliding member base,
A composite fixed to the surface of the sliding member base,
The composite material includes a sliding contact particle in sliding contact with the sliding member, and a composite material base for fixing the sliding contact particle in the sliding member base, and the composite material has 100% by volume of the composite material. It is a sintered body containing sliding contact particles in the range of 20% by volume to 80% by volume,
A sliding member characterized in that the sliding contact particles come in sliding contact with the sliding member by projecting from the surface of the composite base material.
[2] The sliding member according to [1], wherein the composite base material contains one or more selected from ceramics and cermets.
[3] The sliding member according to [1] or [2], wherein the hardness of the sliding contact particles is larger than the hardness of the composite base material.
[4] Cermets and titanium compounds in which the above-mentioned composite base materials include silicon nitride, silicon carbide, alumina, oxide glass, boron carbide, zirconia, silicon oxide, WC ceramics, titanium carbide, titanium diboride, tungsten carbide The sliding member according to [3], comprising at least one material selected from the group consisting of cermets including:
[5] One or more selected from the group consisting of diamond, cubic boron nitride, diamond like carbon, glassy carbon, silicon nitride, silicon carbide, alumina, boron carbide, tungsten carbide and molybdenum carbide The sliding member as described in [3] or [4] characterized by including.
[6] The sliding member according to any one of [1] to [5], wherein an average particle diameter of the sliding contact particles is 10 μm to 250 μm.
[7] The sliding member according to any one of [1] to [6], wherein the thickness of the composite material is 3 mm or more and 5 mm or less.
[8] The sliding member according to [2], wherein the ceramic is composed of at least one selected from a covalent bonding crystal and an ionic bonding crystal.
[9] A pump comprising the sliding member according to any one of [1] to [8].

  According to one aspect of the present invention, it is easy to increase the size of the shaft / bearing structure.

  According to one aspect of the present invention, since the composite base and the sliding contact particles are sintered, the mechanical properties of the base for fixing the sliding contact particles are improved. Furthermore, the sliding particles are excellent in peeling resistance.

  According to one aspect of the present invention, the wear of the sliding member base can be suppressed, and the operation of the pump can be stably continued.

  Also, the composite material can be formed at a desired location of the sliding member base.

It is a cross-sectional schematic which shows the cross section perpendicular | vertical to the axial direction of the axial and bearing structure in one Embodiment of this invention. FIG. 7 is a schematic view showing an embodiment of the shaft member in which the composite material is disposed on the surface of the sliding member base in a scattered manner when viewed from the vertical direction of the surface of the base. When it sees from the perpendicular direction of the surface of a base, it is a mimetic diagram showing one embodiment of a shaft member many arranged in a field which is easy to be loaded among the surfaces of a sliding member base. In one embodiment of the present invention, it is a schematic diagram showing the thickness of a composite material and the average height from the bottom of a composite material to a composite material substrate exposed part. FIG. 7 is a schematic view of the process of fixing the composite material in the recess formed in advance in the sliding member in one embodiment of the present invention, as viewed from the direction perpendicular to the axial direction.

[1. Sliding member]
The sliding member according to an embodiment of the present invention is a sliding member that slides relative to the sliding member, and the sliding member is a sliding member base, and the sliding member base A composite material fixed on the surface of the composite material, the composite material being in sliding contact with the sliding member and a composite base for fixing the sliding particle to the base of the sliding member; A sintered body containing 20% by volume or more and 80% by volume or less of the contact particles with respect to 100% by volume of the composite material, wherein the contact particles protrude from the surface of the composite base material. Thus, the sliding member is in sliding contact with the sliding member.

  According to the above configuration, since the composite base and the sliding contact particles are sintered, the sliding contact particles are firmly fixed to the composite base. Therefore, the sliding particles are excellent in peeling resistance.

  Further, according to the above configuration, since the composite material is a sintered body and can be formed, for example, in a pellet shape, the composite material can be formed at a desired portion of the sliding member base. Therefore, in disposing the sliding contact particles on the sliding member, the degree of freedom in design is high, and it is easy to cope with the increase in size.

  According to the above configuration, the hardness of the composite substrate is high and equal to or higher than the hardness of the silica sand, and therefore, the wear resistance to silica sand or the like contained in the slurry liquid is excellent.

<Structure of Sliding Member>
First, as a sliding member that slides relative to a sliding target member, a shaft member of a shaft / bearing structure in a rotation mechanism used for a pump capable of discharging a slurry liquid will be described. In the present embodiment, although the shaft member as the sliding member is described, the sliding member of the present invention is not necessarily limited thereto. For example, the present invention can also be applied to a bearing member in a shaft / bearing structure that slides relative to the shaft member.

  The configuration of the shaft member 10 as the sliding member of the present embodiment in the shaft / bearing structure 1A will be described based on FIG. FIG. 1 is a schematic cross-sectional view showing a cross section perpendicular to the axial direction of a shaft / bearing structure 1A in the present embodiment.

  As shown in FIG. 1, the shaft / bearing structure 1A is composed of a shaft member 10 as a sliding member and a bearing member 11 as a slidable member. The shaft member 10 is a cylindrical shaft sleeve. The shaft member 10 is not limited to the shaft sleeve, and may be a shaft. On the other hand, the bearing member 11 has a cylindrical shape in which the shaft member 10 is accommodated and supports the shaft member 10.

  The bearing member 11 is made of, for example, a hard ceramic or cemented carbide, and has a hardness equal to or higher than the hardness of silica sand. Therefore, the bearing member 11 is excellent in wear resistance to silica sand or the like contained in the slurry liquid. Furthermore, since the ceramic having covalent or ionic bonds, which is a hard ceramic, has a low affinity to metal components such as metal scraps that are rarely contained in the slurry liquid, it is included in the slurry liquid to the bearing member 11 It is easy to prevent adhesion of metal components such as scrap metal. The surface of the bearing member 11 may be processed so as to form a film having a low coefficient of friction or improve the wear resistance.

  As shown in FIG. 1, the shaft member 10 includes at least a cylindrical base 10 a and a composite 12 fixed on the surface of the base 10 a. The composite 12 includes at least a composite base 12 a and sliding particles 12 b. The slidable particles 12b protrude from the surface of the composite base 12a. In addition, the sliding particles 12b are scattered on the outer surface of the composite base 12a. Therefore, the sliding contact particles 12 b do not exist on the surface of the composite material 12, and a region 13 (hereinafter, the composite material substrate exposed portion) where the composite material substrate is exposed is formed. Furthermore, the composite material 12 is fixed to the surface of the substrate 10a. That is, the composite material 12 is fitted into the recess 10 b of the shaft member 10. Therefore, the composite material 12 is not present on the surface of the shaft member 10, and a region (hereinafter referred to as a substrate exposed portion) 14 where the substrate is exposed is formed. In FIG. 1, only a part of the composite material 12 fixed to the surface of the base 10a is shown. Further, in FIG. 1, only a part of the sliding contact particles 12 b scattered on the outer surface of the composite material 12 is illustrated. Moreover, in FIG. 1, illustration of the raw material particle | grains of the sliding contact particle | grains 12b buried in the composite material 12 is abbreviate | omitted.

The base 10a may be made of, for example, a commonly used material such as SUS304. The hardness of the surface of the base 10a is preferably Hv 400 kg / mm ² or more. The hardness of silica sand or the like contained in the slurry liquid contained in the discharged water is about Hv 1000 kg / mm ² . Therefore, it has been considered preferable to have a hardness close to that value because damage to the substrate 10a due to silica sand or the like contained in the slurry liquid can be reduced. However, in one embodiment of the present invention, since the thickness of the composite material to which the sliding particles 12b are fixed is 3 mm or more as a preferable range, the damage of the base 10a is the peeling resistance and sliding resistance of the sliding particles 12b. The impact on the Therefore, in one embodiment of the present invention, the hardness of the surface of the base 10a may be Hv 400 kg / mm ² or more. Moreover, it is preferable that surface roughness Ra of the base | substrate 10a is 1.0 micrometer or less.

  In one embodiment of the present invention, the sliding member base has a composite 12 secured to its surface. The surface density which is a ratio of the area which the composite material 12 occupies when it sees from the orthogonal | vertical direction of the surface of the axial member 10 is not specifically limited. That is, the composite material 12 may be dispersedly disposed on the surface of the sliding member base, and many of the surfaces of the sliding member base may be disposed in a region (for example, an axial end) to which load is likely to be applied. Good. FIG. 2 is a schematic view showing an embodiment of the shaft member in which the composite material is disposed in a scattered manner on the surface of the sliding member base when viewed from the vertical direction of the surface of the base. Further, FIG. 3 is a schematic view showing an embodiment of a shaft member disposed in a region where load is likely to be applied in the surface of the sliding member base, as viewed from the vertical direction of the surface of the base. .

  In one embodiment of the present invention, the composite material 12 is a sintered body including the composite material base 12 a and the sliding contact particles 12 b of 20% to 80% by volume with respect to 100% of the composite material. Since the composite base 12a and the sliding contact particles 12b are sintered, the sliding contact particles 12b are excellent in peeling resistance. That is, in the shaft / bearing structure having the sliding member according to one embodiment of the present invention, the sliding contact particles 12b are difficult to be separated even if the operation is performed for a long time, so that the sliding can be stably performed for a long time.

  The content of the sliding particles 12b with respect to 100% by volume of the composite material is 20% by volume to 80% by volume, preferably 30% by volume to 70% by volume, and more preferably 40% by volume to 60% by volume. In the present invention, since the sliding particles 12b protrude from the surface of the composite base 12a, it is possible to obtain a sliding member exhibiting excellent slidability.

The thickness of the composite material 12 is not particularly limited as long as the slidable particles 12b come into sliding contact with the member to be slid, but is preferably 3 mm or more and 5 mm or less. According to the above configuration, since the composite material 12 can be manufactured separately from the base 10a, the composite material 12 can be easily manufactured. Furthermore, the required number of the manufactured composite materials 12 may be disposed and fixed to the base 10 a, and the sliding member may be easily manufactured. In addition, with the thickness of the composite material 12, the height from the edge part of sliding contact particle | grains 12b to the bottom face of the composite material 12 is intended. In FIG. 4, a ₁ indicates the maximum height of the composite material 12 from the sliding contact surface 15 to the bottom surface of the composite material 12, and a ₂ indicates the composite material 12 from the sliding contact surface 15 to the bottom surface of the composite material 12. Indicates the minimum height at The average value of the measured value of a _{1 and} the measured value of a _{2 in} the composite material 12 is defined as the thickness of the composite material 12.

The average height from the bottom surface of the composite material 12 to the exposed portion of the composite substrate 13 is not particularly limited as long as the sliding particles 12 b slide on the member to be slid. The average height from the bottom surface of the composite material 12 to the exposed portion of the composite substrate 13 may be the same as the depth of the recess 10 b or may be larger or smaller than the depth of the recess 10 b. The average height from the bottom surface of the composite 12 to the exposed portion of the composite substrate 13 is the same as the depth of the recess 10 b, that is, the exposed portion 13 of the composite substrate is on the same circumference as the surface of the substrate 10 a. Is preferred. In FIG. 4, b ₁ represents the maximum height from the bottom of the composite 12 to the exposed portion 13 of the composite substrate, and b ₂ represents the minimum from the bottom of the composite substrate 12 to the exposed portion 13. Indicates the height of the The average value of the measured value of b _{1 and} the measured value of b _{2 in} the composite material 12 is defined as the average height from the bottom surface of the composite material 12 to the exposed portion 13 of the composite substrate.

  The composite base 12 a preferably contains one or more selected from ceramics and cermets. According to the above configuration, since the hardness of the composite base 12a can be further increased, the wear resistance of the composite base 12a to silica sand or the like contained in the slurry liquid can be improved. Examples of the above-mentioned ceramics include silicon nitride, silicon carbide, alumina, oxide glass, boron carbide, zirconia, silicon oxide, WC ceramics, titanium carbide and titanium diboride. Further, examples of the cermet include cermets containing tungsten carbide and cermets containing a titanium compound. In addition, with WC type | system | group ceramics, the ceramic containing tungsten carbide is intended, for example, WC-TaC-TiC type | system | group ceramics (sintered body of tungsten carbide, a tantalum carbide, and titanium carbide) etc. are mentioned. Further, a cermet containing a titanium compound means a composite metal material of a titanium compound such as titanium carbide, titanium diboride and titanium nitride, and a binder metal such as cobalt and nickel.

  According to the above configuration, since the hardness of the composite base 12a can be further increased, the wear resistance of the composite base 12a to silica sand or the like contained in the slurry liquid can be improved.

  Furthermore, it is preferable that the said ceramic is comprised from 1 or more types chosen from a covalent bond crystal | crystallization and an ionic bondable crystal | crystallization. The term "covalently bonded crystal" is intended to mean a crystal composed of a covalently bonded compound, and examples include silicon nitride and silicon carbide. The term "ion-bound crystal" is intended to mean a crystal composed of a compound having an ionic bond, and examples thereof include alumina and zirconia. Since the composite base 12a is made of these materials, the bonding of metal components such as metal scrap contained in the slurry to the composite base exposed portion 13 can be further suppressed.

  Furthermore, the composite base 12a may contain an intermetallic compound or the like. An intermetallic compound is a compound composed of two or more kinds of metals, and is intended to be a compound having a unique crystal structure different from the original metal and in which elements whose electronic states are largely different are regularly arranged. . When the composite base 12a contains an intermetallic compound, the hardness is larger than that of a normal metal, so that the wear resistance of the composite base 12a to silica sand or the like contained in the slurry liquid can be improved. In addition, when the composite base 12a contains an intermetallic compound, the mechanical properties of the composite base 12a can be improved.

The hardness of the sliding particles 12 b is preferably larger than the hardness of the composite base 12 a. If the composite base 12a and the sliding particles 12b have the above-described configuration, the sliding particles 12b protrude from the surface of the composite base 12a even if there is wear or the like due to silica sand or the like contained in the slurry during operation of the pump. It is easy to maintain the structure. The hardness of the composite base 12a and the hardness of the sliding particles 12b are compared using Hv (Vickers hardness). For example, diamond is Hv 6000 kg / mm ² , silicon nitride Hv 1500 kg / mm ² , silicon carbide Hv 2300 kg / mm ² , alumina Hv 1600 kg / mm ² , zirconia Hv 1300 kg / mm ² , WC ceramics Hv 2000 kg / mm ² , The titanium carbide is Hv 2200 kg / mm ² , and the titanium diboride is Hv 2400 kg / mm ² . Therefore, when the sliding particles 12b are diamond, the composite base 12a is preferably a material softer than diamond, such as silicon nitride, silicon carbide, alumina or zirconia.

Moreover, it is preferable that the hardness of sliding contact particle | grains 12b is more than the hardness of a silica sand. Since the hardness of the silica sand which is the main component of the slurry liquid is about Hv 1000 kg / mm ² , the hardness close to the value or higher hardness reduces or suppresses the damage of the sliding contact particles 12 b by the silica sand. can do. For example, the sliding particles 12 b may be made of diamond, cubic boron nitride, diamond-like carbon (hereinafter referred to as “DLC”), glassy carbon, silicon nitride, silicon carbide, silicon carbide, alumina, boron carbide, tungsten carbide and the like It is preferable to include one or more selected from the group consisting of molybdenum carbide. These may be single crystal particles or sintered bodies. That is, the above-mentioned diamond also includes single crystal particles of diamond and particles obtained by crushing a diamond sintered body. Further, the above-mentioned DLC includes particles obtained by granulating DLC powder using a binder, and particles obtained by crushing a sintered body of DLC powder.

  According to the above-mentioned composition, wear of sliding contact particle 12b by silica sand can be controlled more. In addition, since the friction coefficient of each particle is low, a sliding member containing at least one or more of the particles as sliding particles 12b does not have a lubricant such as water between it and the member to be slid. It can slide smoothly even under non-lubricated conditions. Furthermore, since the coefficient of friction of each particle is low, the generation of heat due to the friction between the sliding particles 12b and the member to be slid is suppressed, and the durability of the sliding member is improved.

  The average particle diameter of the sliding particles 12 b is preferably 10 μm or more and 250 μm or less. More preferably, they are 20 micrometers or more and 200 micrometers or less, More preferably, they are 20 micrometers or more and 100 micrometers or less. The average particle size is a value measured by a laser diffraction type particle size distribution measuring apparatus: SALD-2100 manufactured by Shimadzu Corporation.

  In general, the step of producing the composite material 12 includes the step of processing the tip of the sliding contact particle 12 b. The "average particle diameter of sliding contact particles" in the present specification means the average particle diameter of the sliding contact particles 12b before the above processing is performed. The composite material may be particles of the same material as the sliding contact particles 12 b and may have particles having a smaller average particle diameter than the sliding contact particles 12 b. The particles are, for example, particles which are unavoidably provided due to the particle size distribution of the powder serving as the raw material of the sliding contact particles 12 b when manufacturing the shaft member 10.

  Average height from the surface of the composite material base exposed portion 13 to the tip of the sliding contact particle 12b (that is, the height from the surface of the composite base material exposed portion 13 to the sliding contact surface 15, hereinafter "protrusion height" Is preferably 0.8 μm or more, and more preferably 1.0 μm or more. In addition, with the tip of sliding contact particle 12b in projection height, the tip of sliding contact particle 12b after performing the above-mentioned processing is intended.

  Further, the protrusion height is preferably 40% or less of the average particle diameter of the sliding particles, and more preferably 30% or less. That is, for example, if the average particle diameter of the sliding particles is 150 μm, the protrusion height is preferably 60 μm or less, and more preferably 45 μm or less. If the protruding height is in the above-described configuration, the fixing strength of the sliding contact particles 12 b tends to be large.

  The tip of each sliding particle 12 b, that is, the end on the bearing member 11 side, is preferably on the same circumference centering on the axis of the shaft member 10 when viewed from the axial direction of the shaft member 10. That is, as shown in FIG. 1, it is preferable that the sliding contact surface 15 which is a circumferential surface centering on the axis of the shaft member 10 is formed by the tip of each sliding contact particle 12b. The sliding contact surface 15 is in sliding contact with the bearing member 11 which is a slidable member when the shaft member 10 rotates.

  According to the above configuration, when the shaft member 10 rotates, only the sliding contact particle 12 b is in sliding contact with the bearing member 11. Therefore, since the shaft member 10 has a low coefficient of friction and suppresses the generation of heat due to friction, the durability is further improved.

  The surface density, which is the ratio of the area occupied by the sliding particles 12b when viewed from the vertical direction of the surface of the composite material 12, is preferably 20% to 70%, and is 40% to 60%. Is more preferred. If it is the said structure, it will become easy to maintain appropriately the load added to each sliding contact particle.

  In one embodiment of the present invention, the method of fixing the composite material 12 to the sliding member is not particularly limited, but the composite material 12 may be fixed to the recess 10b of the sliding member by brazing, press fitting, cold fitting, shrink fitting or the like. The method of fixing is mentioned.

  In one embodiment of the present invention, the procedure for fixing the composite material 12 to the sliding member is not particularly limited. For example, after the composite material 12 is manufactured first, the composite material 12 is formed in advance on the sliding member There is a method of fixing in the recessed portion 10b.

  FIG. 5 is a schematic view of the process of fixing the composite material in the recess formed in advance in the sliding member in one embodiment of the present invention as viewed from the direction perpendicular to the axial direction.

  According to the above method, the composite material 12 can be strongly fixed by the sliding member, which facilitates manufacture. In addition, the composite material 12 can be fixed to any position of the sliding member base.

  As a method of fixing the composite material 12 to the shaft member 10 as the sliding member, the composite material 12 is manufactured first, and then the composite material 12 is fixed to the sliding member by hot isostatic pressing or the like. Methods are also included.

  After the composite material 12 is fixed to the sliding member, it may be further processed so that the particle tips of the sliding particles 12b are on the same circumference. That is, by making the distances from the central axis of rotation of the base 10a to the outermost particle tip equal, the particle tips of the sliding particles 12b are on the same circumference.

  The method of producing the composite material 12 in the embodiment of the present invention will be described below. The composite material 12 is a sintered body including the composite material base 12 a and the sliding contact particles 12 b. Therefore, the production method is not particularly limited as long as the composite base 12a and the sliding particles 12b can be sintered. For example, the method of producing the composite material 12 includes the following steps (i) to (iii).

(I) a step of obtaining a mixed powder of a composite substrate and sliding particles,
(Ii) filling the mixed powder obtained in (i) in a mold and sintering, and (iii) processing the surface of the sintered body obtained in (ii), a structure in which sliding particles protrude Process of forming

  In the step (i), the volume fraction of the sliding particles is preferably 20% to 80% by volume, more preferably 30% to 70% by volume, based on 100% by volume of the mixed powder. . Moreover, it is preferable that the volume fraction of a composite material base material with respect to 100 volume% of mixed powder is the remainder which deducted the volume fraction of sliding contact particle | grains. That is, the volume fraction of the composite base is preferably 20% to 80% by volume, and more preferably 30% to 70% by volume, with respect to 100% by volume of the mixed powder.

  In the step (ii), examples of the sintering method include spark plasma sintering (hereinafter referred to as SPS), hot isostatic pressing (hereinafter referred to as HIP) and the like.

  The sintering condition in the SPS method is preferably 5 MPa or more and 30 MPa or less at sintering, and more preferably 10 MPa or more and 20 MPa or less. Further, the maximum heating temperature at the time of sintering is preferably 1000 ° C. or more and 1850 ° C. or less, and more preferably 1200 ° C. or more and 1600 ° C. or less. Furthermore, the holding time of the maximum heating temperature is preferably 10 minutes or more and 60 minutes or less, and more preferably 10 minutes or more and 30 minutes or less. If the holding time of the maximum heating temperature is within the above-mentioned preferable range, the degeneration of the diamond can be suppressed as much as possible. Moreover, also in materials other than diamond, in order to improve productivity, it is preferable that the holding time of the maximum heating temperature is in the above range.

  In the process of producing the sintered body, for example, when heated to 1500 ° C., the diamond does not reach a thermodynamic equilibrium unless it is pressurized to 4500 MPa or more. Here, the SPS method has the advantage of simultaneously pressurizing the material to high pressure, promoting bonding between the particles by plasma formation or the like, and simultaneously performing rapid heating to a high temperature. By using the SPS method, sintering can be performed at a high temperature and a high pressure in a short time, so that a composite material can be suitably produced even when the sliding particles are diamond.

  As for the sintering conditions in the HIP method, the pressure at the time of sintering is preferably 100 MPa or more and 200 MPa or less, and more preferably 100 MPa or more and 150 MPa or less. Further, the maximum heating temperature at the time of sintering is preferably 1000 ° C. or more and 1850 ° C. or less, and more preferably 1200 ° C. or more and 1600 ° C. or less. Furthermore, the holding time of the maximum heating temperature is preferably 10 minutes or more and 60 minutes or less, and more preferably 10 minutes or more and 30 minutes or less.

  In the process of producing the sintered body, for example, by coating the diamond with another material and lowering the heating temperature, the sintered body can be produced while maintaining the diamond even if the pressure is lowered. Therefore, by using the HIP method, even when the sliding particles are diamond, a composite material can be suitably produced.

  As a method of processing the surface in the step (iii), for example, a method of scraping the surface of a sintered body with a grindstone such as diamond and silicon carbide, a method of electrical discharge machining, a method of polishing using a polishing machine, etc. can be used. . A person skilled in the art may select an appropriate method for grinding a high hardness material such as the composite substrate 12a and the sliding particles 12b in one embodiment of the present invention.

  The step (iii) may be performed after the composite material 12 is fixed to the sliding member.

[2. pump〕
A pump according to an embodiment of the present invention includes the sliding member described above. Therefore, the wear of the sliding member base can be suppressed, and the operation of the pump can be stably continued.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in the different embodiments. Is also included in the technical scope of the present invention.

A sintered body was produced as described below using the following components.
Diamond particles (average particle diameter 40 μm, product name: IMS-E400 / 500, manufactured by Tomei Diamond Corporation)
Diamond particles (average particle diameter 76 μm, product name: TMS-E 200/230, manufactured by Tomei Dia Co., Ltd.)
Alumina particles (average particle size 0.2 μm, product name: TM-5D, manufactured by Daimei Chemical Industries, Ltd.)
・ Si-AL-Ca-Mg-based oxide glass powder (average particle diameter 13 μm, product name: CF0055, manufactured by Nippon Frit Co., Ltd.)
· Silicon nitride sintered body pulverized particles (average particle diameter 100 μm, product name: KN-101 pulverized powder, manufactured by Kubota Corporation, hereinafter, also referred to as "silicon nitride particles")
Silicon carbide particles (average particle diameter 3 μm, product name: CP # 4000, manufactured by Shin-Etsu Smelting Co., Ltd.)
Silicon particles (average particle diameter 25 μm, product name: No. 350, Yamaishi Metal Co., Ltd.)
<Production Example 1>
Diamond particles having an average particle diameter of 40 μm and alumina particles having an average particle diameter of 0.2 μm were dry mixed at a volume ratio of 30:70. Thereafter, the obtained mixed powder is powder-filled into a graphite mold having an inner diameter of 20 mm, and then pressure sintering is carried out under conditions of 15 MPa 1200 ° C. for 10 minutes using an SPS device (product name: SPS-1030, manufactured by Sumitomo Coal Mining Co., Ltd.) Did. It took out from a graphite type | mold and obtained the sintered compact of (phi) 20 mm x height 5 mm. The surface of the obtained sintered body is polished using a diamond grindstone, and then the surface of the obtained sintered body is polished using a silicon carbide grindstone to produce a composite material in which diamond particles are protruded from the surface. did. Silicon carbide is softer than diamond and harder than alumina. Therefore, when the surface of the sintered body is polished using a silicon carbide grinding wheel, only alumina particles are polished, and as a result, a composite in which diamond particles are protruded can be produced.

<Production Example 2>
Dry mixing of diamond having an average particle size of 76 μm, alumina having an average particle size of 10 μm, and Si-AL-Ca-Mg-based oxide glass powder having an average particle size of 13 μm at a volume ratio of 30:49:21, 15 MPa 1000 ° C. 10 A composite material was obtained in the same manner as in Production Example 1 except that the pressure sintering was performed under the conditions of 1 min.

<Production Example 3>
Silicon nitride particles having an average particle diameter of 100 μm and a Si-AL-Ca-Mg-based oxide glass powder having an average particle diameter of 13 μm were dry-mixed at a volume ratio of 30:70. Thereafter, the obtained mixed powder was powder-filled in a graphite mold with an inner diameter of 20 mm, and then pressure sintering was performed under the conditions of 15 MPa, 1000 ° C., and 10 minutes using an SPS apparatus. It took out from a graphite type | mold and obtained the sintered compact of (phi) 20 mm x height 5 mm. The surface of the obtained sintered body is polished using a diamond whetstone, and then the surface of the obtained sintered body is polished using an alumina whetstone to obtain a composite material in which silicon nitride particles protrude from the surface. Made. Since oxide glass is softer than silicon nitride, a composite material in which silicon nitride particles are protruded can be produced by processing with an alumina grinding wheel.

Production Example 4
Diamond particles having an average particle diameter of 40 μm, silicon carbide particles having an average particle diameter of 5 μm, and silicon particles having a particle diameter of 25 μm were dry mixed at a volume ratio of 45: 6: 49, respectively. Thereafter, the obtained mixed powder is formed into an inner diameter of 20 mm by a dry press, vacuum-sealed in a glass capsule, and then 100 MPa at 1450 ° C. Sintering was performed under the following conditions. It took out from a graphite type | mold and obtained the sintered compact of (phi) 20 mm x height 5 mm. The surface of the obtained sintered body is polished using a diamond whetstone, and then the surface of the obtained sintered body is polished using a silicon carbide whetstone to produce a composite material in which the diamond particles protrude from the surface. did.

<Comparative Production Example 1>
A composite material was obtained in the same manner as in Production Example 1 except that in the production example 1 the projecting process by the silicon carbide grinding wheel was not performed.

<Comparative Production Example 2>
A diamond with an average particle diameter of 40 μm was electrodeposited and fixed on SUS 304 of φ 20 mm × height 5 mm by Ni-P plating, and then the diamond was polished to obtain a composite material with a protruding height of 10 μm. The volume ratio of diamond to SUS304 was 30:70.

[Examples 1 to 4, Comparative Example 1]
<Friction wear test>
In Examples 1 to 4, for the composites obtained in Production Examples 1 to 4, as Comparative Example 1, the composite obtained in Comparative Production Example 1 is combined with a silicon nitride ring of φ 140 mm / φ 106 mm × height 6 mm, The test body was produced. The friction coefficient of 1 hour is obtained by pressing the silicon nitride block of 18 × 12 × 6 mmt (surface of test surface 18 × 12) on the test body rotating under the conditions of 2 kg / cm ^{2 of} surface pressure and 2 m / sec of peripheral speed. It was measured. The average value of the friction coefficient measured for one hour is shown in Table 1.

  From the comparison between Examples 1 to 4 and Comparative Example 1, it was found that the friction can be reduced by projecting the sliding particles even when the volume fraction of diamond is low.

[Example 5, Comparative Example 2]
<Slurry abrasion test>
The slurry liquid was prepared by adding silica sand obtained by mixing silica sand having an average particle diameter of 5 μm and silica sand having an average particle diameter of 30 μm at a weight ratio of 50:50 to 3000 ppm in water and stirring. . The average particle size of silica sand is a value measured by a laser diffraction particle size distribution measuring apparatus: SALD-2100, manufactured by Shimadzu Corporation. Test section (Example 5) using a mixture obtained by adding 1 L of the slurry liquid and the sintered body obtained in Production Example 1 in a 1 L pot, and 1 L of the slurry liquid in a 1 L pot and obtained in Comparative Production Example 2 A test section (comparative example 2) using a mixture to which the composite material was added was prepared, and the above mixture was stirred at a rotational speed of 100 rpm (3 m / min), respectively, and then the change in the protrusion of diamond in the composite material was observed .

  From the comparison between Example 5 and Comparative Example 2, it was found that the wear resistance of the sliding member base to the particles contained in the slurry liquid was improved by sintering the sliding particles and the composite base. .

  The present invention can be suitably used for a pump, for example, a leading standby pump.

1A Axis / Bearing Structure 10 Shaft Member 10a Base Body 10b Recess 11 Bearing Member 12 Composite Material 12a Composite Material Base Material 12b Sliding Contact Particles 13 Composite Material Base Material Exposed Area 14 Base Material Exposed Area 15 Sliding Surface

Claims (9)

A sliding member that slides relative to the sliding member,
The sliding member is
A sliding member base,
A composite fixed to the surface of the sliding member base,
The composite material includes a sliding contact particle in sliding contact with the sliding member, and a composite material base for fixing the sliding contact particle in the sliding member base, and the composite material has 100% by volume of the composite material. It is a sintered body containing sliding contact particles in the range of 20% by volume to 80% by volume,
A sliding member characterized in that the sliding contact particles come in sliding contact with the sliding member by projecting from the surface of the composite base material.   The sliding member according to claim 1, wherein the composite base includes one or more selected from ceramics and cermets.   The sliding member according to claim 1 or 2, wherein the hardness of the sliding contact particles is larger than the hardness of the composite base material.   The above composite substrate comprises a cermet containing titanium nitride, silicon nitride, silicon carbide, alumina, oxide glass, boron carbide, zirconia, silicon oxide, WC ceramics, titanium carbide, titanium diboride, tungsten carbide, and a titanium compound The sliding member according to claim 3, comprising at least one material selected from the group consisting of   The sliding particles include one or more selected from the group consisting of diamond, cubic boron nitride, diamond like carbon, glassy carbon, silicon nitride, silicon carbide, alumina, boron carbide, tungsten carbide and molybdenum carbide. The sliding member according to claim 3 or 4, characterized in that:   The sliding member according to any one of claims 1 to 5, wherein an average particle diameter of the sliding contact particles is 10 μm or more and 250 μm or less.   The sliding member according to any one of claims 1 to 6, wherein a thickness of the composite material is 3 mm or more and 5 mm or less.   The sliding member according to claim 2, wherein the ceramic is composed of at least one selected from a covalent bonding crystal and an ionic bonding crystal.   A pump comprising the sliding member according to any one of claims 1 to 8.

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