JP6420272B2 - Sliding member - Google Patents

Description

  The present invention relates to a sliding member that can be suitably used for a prior standby operation pump.

  A prior standby operation pump is known as a kind of drainage pump. The advance standby operation pump can be operated in advance at full speed (advance standby operation) in an anhydrous state, or can be discharged in a gas-water mixed state, in order to cope with a sudden increase in water volume such as guerrilla heavy rain. It has become. Patent Documents 1 to 3 disclose shaft / bearing structures applicable to such a preceding standby operation pump.

  Patent Document 1 discloses a shaft / bearing structure for a pump, which includes a segment made of a cemented carbide base and a diamond sintered body layer formed on the substrate, and a plurality of the segments constitute a bearing. Is disclosed. The inner surface (surface) of the diamond sintered body layer is a sliding surface.

  Patent Document 2 discloses a sintered product configured by adhering or embedding diamond particle clusters (CD) having a particle size of 200 mm (20 nm) or less in the surface portion of a sintered body.

Japanese Patent Laying-Open No. 2005-344878 (released on December 15, 2005) JP 2002-363616 A (published on December 18, 2002) Japanese Patent Laid-Open No. 5-52222 (published March 2, 1993)

  The conventional shaft / bearing structure described in Patent Document 1 and Patent Document 2 has the following problems. FIG. 8 is a schematic sectional view of a sliding surface in the shaft / bearing structure for a pump described in Patent Document 1. The diamond sintered body layer 102 </ b> B includes a diamond portion 130 and a non-diamond portion having a higher friction coefficient than the diamond portion 130. Therefore, the non-diamond portion is exposed on the surface of the diamond sintered body layer 102B. Therefore, when the entire surface of the diamond sintered body layer 102B slides, a portion other than the diamond portion 130 can slide with the counterpart material. Therefore, the coefficient of friction cannot be made very low. Similarly, also in the sintered product described in the conventional patent document 2, a CD having a low friction coefficient and other sintered body portions exist on the surface. The sliding counterpart material slides not only the CD but also the sintered body itself. For this reason, the improvement of the friction coefficient is limited.

  In addition, when a slurry liquid in which a solid material with high hardness and water are mixed inside the pump and the slurry liquid enters the sliding surface for some reason, the non-diamond portion has a relatively low hardness on the sliding surface. Solid objects may bite or scratch. As a result, an increase in the coefficient of friction, vibration due to scratches, and the like may occur, shortening the life of the bearing.

  Therefore, as disclosed in Patent Document 3, a technique has been developed in which one of a sleeve or a bearing is coated with a hard coating having a good sliding property such as diamond of several μm, and the hard coating is used as a sliding surface. Yes. Thereby, since the whole base | substrate surface is covered with the hard film, only a hard film slides with the other party material, and slidability improves. However, hard coatings often have different coefficients of thermal expansion from the substrate. Therefore, the thermal stress at the time of sliding becomes large, and cracks and peeling may occur in the hard film. Therefore, in order to match the thermal expansion coefficient with the hard coating, there is a problem that the material selection of the substrate is restricted.

  The present invention has been made in view of the above-described conventional problems, and an object of the present invention is to provide a sliding member having good sliding properties and a wide range of material selection for a substrate.

  In order to solve the above problems, the sliding member of the present invention is a sliding member that slides relative to the sliding member, and includes a sliding member base and a surface of the sliding member base. And slidable contact particles that are slidably contacted with the sliding member, and the sliding contact particles protrude from the surface of the sliding member base.

  According to the above configuration, the sliding contact particles are scattered and fixed on the surface of the sliding member base, and protrude from the surface of the sliding member base. Therefore, the sliding member is in sliding contact with the tip portion of the sliding contact particle, and is not in sliding contact with the surface of the sliding member base. Thereby, the sliding member has a low friction coefficient, heat generation due to friction is suppressed, and durability of the material is improved.

  Further, since the sliding contact particles are scattered on the outer surface of the sliding member base, a region where no sliding contact particles exist (interparticle region) is formed between the sliding contact particles. Therefore, when the sliding member base is thermally expanded due to an increase in temperature, the sliding contact particles fixed on the outer surface of the sliding member base can move accompanying the thermal expansion. In other words, the sliding contact particles move in association with the thermal expansion of the sliding member base. Therefore, it is not necessary to match the thermal expansion coefficients of the sliding member base and the sliding contact particles, and the selectivity of the material of the sliding member base is wide.

  In addition, when the sliding member is used, for example, in a shaft / bearing structure having a pump shaft and a bearing, when the sliding member rotates, a moderate amount of water is slid between the sliding particles and the sliding member from the interparticle region. Is supplied as a lubricant to improve lubricity. This is because when the sliding contact particles are fixed, water is easily stored by forming an interparticle region surrounded by irregularities of various shapes including reverse taper etc. that can not be obtained by machining, This is because it can be discharged.

  In the sliding member of the present invention, the average height from the surface of the sliding member base to the tip of the sliding contact particle may be 0.8 μm or more.

  In the sliding member, the sliding contact particle protrudes from the surface of the sliding member base, the sliding member is in sliding contact with the tip of the sliding contact particle, and is not in sliding contact with the surface of the sliding member base. The average height from the surface of the sliding member base to the tip of the sliding contact particles is preferably 0.8 μm or more.

  Further, as described above, the average height from the surface of the sliding member base to the tip of the sliding contact particle is, as described above, when the sliding member is used in, for example, a shaft / bearing structure having a pump shaft and a bearing. Is more preferably 1.0 μm or more for ensuring the function of improving the lubricity. Furthermore, the average height from the surface of the sliding member base to the tip of the sliding contact particles is preferably 50 μm or more so that more appropriate water can be stored even when the sliding member base is thermally expanded. In order to be supplied as a lubricant more appropriately, the thickness is preferably 150 μm or less.

  The sliding member of the present invention has a configuration in which the sliding member is load-supported by a plurality of the sliding particles.

  According to the above configuration, the sliding member supports the sliding member by a plurality of sliding contact particles so that the sliding member comes into sliding contact with the tip of the sliding contact particle, and the surface of the sliding member base The state which does not slidably contact can be maintained.

  In the sliding member of the present invention, the sliding contact particles preferably have a hardness equal to or higher than that of silica sand. According to the above configuration, since the sliding contact particles have a hardness equal to or higher than that of silica sand, it is possible to prevent the sliding contact particles from being worn by slurry particles having silica sand as a main component.

  In the sliding member of the present invention, the sliding contact particles are diamond particles, diamond-like carbon particles, cubic boron nitride, glassy carbon particles, alumina particles, boron carbide particles, silicon carbide particles, tungsten carbide particles, silicon nitride particles. And it is good also as a structure containing at least 1 or more types among molybdenum carbide particles.

  According to the above configuration, since each of the particles has a low coefficient of friction, a sliding member including at least one of the particles as a sliding contact particle is lubricated with water or the like between the sliding member and the sliding member. It can slide smoothly even under non-lubricated conditions where no agent is present. Furthermore, since the friction coefficient is low, the generation of heat due to friction is suppressed, and the durability of the material is improved.

  In the sliding member of the present invention, the sliding member base may include a base and non-sliding contact particles fixed to the outer surface of the base and having a particle size smaller than the sliding contact particles.

  According to the above configuration, the sliding member base includes the base and the non-sliding contact particles fixed to the outer surface of the base and having a particle size smaller than the sliding contact particles. Even if it exists, the situation where a base | substrate wears out by the particle | grains which entered between the sliding contact particles can be prevented. For example, when the sliding member is used in a shaft / bearing structure having a pump shaft and a bearing, slurry particles contained in water enter between the sliding contact particles. In this case, it is possible to prevent the substrate from being worn by the slurry particles and protect the substrate.

  The sliding member of the present invention preferably has a surface density of 20 to 70%, which is a ratio of the area occupied by the sliding contact particles when viewed from the vertical direction of the surface of the sliding member base. By setting the surface density to 20 to 70%, when the sliding member is used, for example, in a shaft / bearing structure having a pump shaft and a bearing, slurry particles such as earth and sand contained in water to be discharged from the pump are removed. Easier escape to the interparticle region. When the areal density is less than 20%, the interval between the sliding contact particles becomes too wide, so that the load applied to each sliding contact particle becomes large, resulting in a problem in durability. Therefore, it is more preferable to set it as 30% or more. In addition, when the surface density exceeds 70%, the sliding contact particle interval becomes narrow, and it becomes difficult to store water between the sliding contact particles, or the stored water is difficult to be discharged. Therefore, it is more preferably 60% or less, and still more preferably 55% or less. As a result, it is possible to suppress wear of the member to be slid, which is the counterpart material, due to the entrainment of the slurry particles between the sliding particles and the member to be slid.

  In the sliding member of the present invention, the average particle diameter of the sliding contact particles is preferably 10 μm to 500 μm. When the average particle diameter is smaller than 10 μm, the force for holding the sliding contact particles is small, so that the particles easily fall off from the sliding member base. Therefore, it is preferably 40 μm or more, and more preferably 80 μm or more. On the other hand, when the average particle size is larger than 500 μm, conditions such as pressure applied at the time of production are increased, and a large amount of cost is required for equipment, so 500 μm is the upper limit. Further, in order to more efficiently process the tip of the sliding contact particle, the average particle diameter is preferably 200 μm or less, and more preferably 150 μm or less.

  In the sliding member of the present invention, the sliding member base may include a base and a metal film formed on the surface of the base. The metal film functions as a fixing member for fixing the slidable contact particles, and can prevent a situation in which the substrate is worn due to contact with other particles. For example, when the sliding member is used for a shaft / bearing structure having a pump shaft and a bearing, if the material of the substrate is softer if a material harder than slurry particles contained in water is used as the metal film, Even so, it is possible to prevent the substrate from being worn by the slurry particles passing through the interparticle region. That is, the substrate can be protected by the metal film.

The sliding member of the present invention preferably has the hardness of the surface of the sliding member base portion and Hv600kg / mm ² or more, and more preferably Hv800kg / mm ² or more. When the sliding member is used, for example, in a shaft / bearing structure having a pump shaft and a bearing, the hardness of the slurry particles contained in the discharged water is about Hv 1000 kg / mm ^2. By having it, damage to the substrate due to the slurry particles can be reduced.

  The sliding member for the sliding member of the present invention is preferably ceramics or cermet. Thereby, durability as a to-be-slidable member improves.

  In the sliding member of the present invention, the sliding contact particles are preferably electrodeposited and fixed onto the sliding member base. Thereby, the sliding contact particles can be fixed on the sliding member base under atmospheric pressure conditions.

  In the sliding member of the present invention, it is preferable that at least a part of the sliding contact particle is covered with a coating. According to said structure, the corner | angular part of the front-end | tip of sliding contact particle | grains can be covered so that the surface may become a smooth surface with a film, and the sliding contact surface of a sliding member can be made into a smooth surface.

  In the sliding member of the present invention, the coating film may cover at least the tips of the sliding particles and be made of a diamond-like carbon film or a glassy carbon film.

  According to the above configuration, the corner of the tip of the slidable contact particle can be covered with the coating made of the diamond-like carbon film or the glassy carbon film so that the surface becomes a smooth surface, and the slidable contact surface of the shaft member can be covered. Furthermore, a smooth surface can be obtained.

  In the sliding member of the present invention, the coating film is formed of a diamond-like carbon film or a glassy carbon film covering the periphery of the tip surface, and the outer surface of the coating film corresponding to the corner from the tip surface to the side surface is a curved surface. It is good also as composition which becomes.

  According to the above configuration, the coating made of the diamond-like carbon film or the glassy carbon film covers the periphery of the tip surface of the slidable contact particle and corresponds to the corner corresponding to the corner from the tip surface to the side surface of the slidable contact particle. The outer surface is curved. Therefore, the smoothness of the sliding contact surface of the sliding member can be further improved, and the aggressiveness to the sliding surface by the corner portion can be reduced.

  The sliding member of the present invention may be used in a shaft / bearing structure having a shaft and a bearing, and the tip of the sliding contact particle may be on the same circumference centering on the shaft of the shaft / bearing structure. .

  According to the above configuration, when the sliding member is used in a pump shaft / bearing structure including the sliding member and the slidable member, the sliding member and the slidable member are slid when the sliding member rotates. Only the sliding particles are in contact. Therefore, the sliding member has a low coefficient of friction, suppresses the generation of heat due to friction, and improves the durability of the material.

  The pump according to the present invention has any one of the sliding members described above. According to said structure, since a sliding member has a low friction coefficient, generation | occurrence | production of the heat by friction is suppressed and durability of material improves, Therefore The durability of a pump can be improved.

  According to one embodiment of the present invention, it is possible to provide a sliding member that has good slidability and a wide range of material selection for a substrate.

It is a section schematic diagram showing a section perpendicular to the direction of an axis of a shaft member as a shaft and bearing structure and a sliding member in Embodiment 1 of the present invention. It is a top view which shows the structure seen from the outer surface side of the said shaft member. It is sectional drawing which shows the state by which the sliding contact particle of the said shaft member was electrodeposited on the base | substrate. (A) is a figure which shows the flow when a sliding contact particle is fixed on a base | substrate using SPS, (b) is sectional drawing which shows the state by which the sliding contact particle was fixed by SPS on the base | substrate. After the mixed powder of the sliding contact particles and the hard metal powder of the shaft member is placed on the substrate, it is pressure-molded using an SPS device, and then processed to form a hard metal film between the particles of the sliding contact particles. It is a figure which shows the flow in the case of forming. It is sectional drawing which shows the state at the time of mounting a sliding-contact particle powder on it, after mounting a hard metal powder layer on the base | substrate of the said shaft member. It is sectional drawing which shows the state in which the sliding contact particle and the hard particle | grain of the shaft member in Embodiment 2 of this invention were fixed on the base | substrate. It is the cross-sectional schematic which shows the cross section of the sliding surface of the conventional shaft and bearing structure for pumps. 9A is a cross-sectional view of the shaft member according to Embodiment 3 of the present invention, and FIG. 9B is an enlarged view of a part of the shaft member shown in FIG. 9A. is there. (A) of FIG. 10 is a schematic diagram showing a cross section of the shaft member, showing a first method of forming the sliding contact surface of the sliding contact particle having the coating film shown in FIG. 9, and (b) of FIG. These are the schematic diagrams which show the cross section of the shaft member which shows the 2nd formation method of the sliding contact surface of the sliding contact particle which has a film shown in FIG. FIG. 11A is a cross-sectional view of the shaft member according to the fourth embodiment of the present invention. FIG. 11B is an enlarged view of the slidable contact particle shown in FIG. FIG. 6 is a longitudinal sectional view showing a configuration of a sliding contact member according to still another embodiment of the present invention, in which a sliding member base portion is composed only of a base. It is a slidable contact member of further another embodiment of this invention, Comprising: It is a longitudinal cross-sectional view which shows the structure of the slidable contact member which a sliding member base consists of a surface formation thing provided on the outer surface of the base | substrate and the base | substrate. .

[Embodiment 1]
An embodiment of the present invention will be described below with reference to FIGS. In the present embodiment, as a sliding member that slides relative to the sliding member, a shaft of a rotation mechanism used in a pump for discharging water containing earth and sand (slurry particles) and a shaft of a bearing structure The member will be described. In the present embodiment, a shaft member as a sliding member will be described, but the sliding member of the present invention is not necessarily limited thereto. For example, the present invention can be applied to a bearing member in a shaft / bearing structure that slides relative to the shaft member.

<Configuration of sliding 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 with reference to FIGS. FIG. 1 is a schematic cross-sectional view showing a cross section perpendicular to the axial direction of the shaft / bearing structure 1A in the present embodiment. FIG. 2 is a top view showing a configuration of the shaft member 10 provided in the shaft / bearing structure 1A as viewed from the outer surface side.

  As shown in FIG. 1, the shaft / bearing structure 1 </ b> A includes a shaft member 10 as a sliding member and a bearing member 11 as a sliding 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, hard ceramic or cemented carbide, and is preferably ceramic or cermet. By using ceramics or cermet, the durability of the bearing member 11 is improved. The inner surface of the bearing member 11 is preferably such that the unevenness of the surface does not reach the region depth between sliding contact particles described later in the shaft member 10 that is a sliding member, but the surface roughness Ra is 1.0 μm or less. If there is no problem, it will not affect the friction so much. In addition, the surface of the bearing member 11 may be processed so as to form a sintered body or a film for reducing the friction coefficient or improving the wear resistance.

  As shown in FIG. 1, the shaft member 10 includes at least a cylindrical base body 10a and sliding contact particles 10b scattered and fixed on the outer surface of the base body 10a. Further, since the sliding contact particles 10b are scattered on the outer surface of the substrate 10a, a region 12 (hereinafter referred to as an interparticle region) 12 where the sliding contact particles 10b do not exist is formed between the sliding contact particles 10b. In FIG. 1, only a part of the sliding contact particles 10b scattered on the entire outer surface of the substrate 10a is illustrated.

  Further, the shaft member 10 may include a fixing member (not shown in FIG. 1) for fixing the sliding contact particles 10b on the outer surface of the base body 10a.

  Further, the shaft member 10 may include particles in the interparticle region 12 that are made of the same material as the sliding contact particle 10b and have a smaller particle diameter than the sliding contact particle 10b. The particles are particles inevitably provided due to the particle size distribution of the powder that is the raw material of the sliding contact particles 10b when the shaft member 10 is manufactured.

The base 10a is made of a generally used material, and is made of, for example, a Co-based or Ni-based hard alloy. The hardness of the substrate 10a is preferably Hv 600 kg / mm ² or more. Since the hardness of the slurry particles contained in the discharged water is about Hv 1000 kg / mm ² , the hardness of the slurry particles close to that value can reduce damage to the substrate 10a due to the slurry particles. Further, the surface roughness Ra of the substrate 10a is preferably 1.0 μm or less.

  The sliding contact particle 10b includes at least one or more of diamond particles, diamond-like carbon particles (hereinafter referred to as DLC particles), cubic boron nitride, and glassy carbon particles. Here, the diamond particles include diamond single crystal particles and particles obtained by pulverizing a diamond sintered body. The DLC particles include particles obtained by granulating DLC powder using a binder and particles obtained by pulverizing a sintered body of DLC powder.

  The slidable contact particle 10b is fixed on the outer surface of the substrate 10a by a method described later. The sliding contact particles 10b are scattered with a thickness of one particle on the outer surface of the substrate 10a. That is, another sliding contact particle 10b is hardly fixed on the particle of the sliding contact particle 10b fixed on the base body 10a. Moreover, the shaft member 10 has the inter-particle area | region 12 in which the sliding contact particle | grains 10b do not exist. Therefore, even if expensive diamond particles are used as the sliding contact particles 10b, the total amount of the sliding contact particles 10b fixed on the surface of the substrate 10a is the same as that of Patent Document 1, in which the diamond sintered body is used as the sliding contact surface. Compared with the case of using, it can reduce significantly and can reduce manufacturing cost. It should be noted that there may be a location where two or more different sliding contact particles 10b are adjacent on the outer surface of the substrate 10a. However, the adjacent sliding contact particles 10b are not joined.

  Further, the tip of each sliding contact particle 10 b, that is, the end on the side of the bearing member 11 is on the same circumference centered 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, a sliding contact surface 13 that is a circumferential surface around the axis of the shaft member 10 is formed by the tip of each sliding contact particle 10 b. When the shaft member 10 rotates, the sliding contact surface 13 comes into sliding contact with the bearing member 11 which is a sliding member.

  Further, an interparticle region 12 is formed between the sliding contact particles 10b as shown in FIGS. Conventionally, as described in Patent Document 1 or Patent Document 3, in the case where a sintered body or a hard film is formed on a substrate, when the temperature rises, the substrate and the sintered body or Peeling due to the difference in thermal expansion from the hard coating can occur. Therefore, it is necessary to match the thermal expansion coefficients of the base and the sintered body or the hard coating. Therefore, it is necessary to use a cemented carbide containing expensive WC as the substrate, and there is a problem that the selection range of the material of the substrate is narrow. This was the same even when the segment system was used as in Patent Document 1. On the other hand, in the shaft member 10 in the present embodiment, the interparticle region 12 is formed between the sliding contact particles 10b forming the sliding contact surface 13, so that the problem can be solved. This will be described in detail below.

  First, the peeling due to the difference in thermal expansion as described above is caused by exerting a force to break the sintered body or the hard film by thermal expansion on the substrate side having a relatively large thermal expansion coefficient. . Also in the present embodiment, the thermal expansion coefficients of diamond particles and DLC particles as the sliding contact particles 10b are small, and the thermal expansion coefficient of an alloy or the like used for the base 10a is relatively large. However, in the shaft member 10 according to the present embodiment, when the base body 10a is thermally expanded due to an increase in temperature, the sliding contact particles 10b fixed on the outer surface of the base body 10a move in association with the thermal expansion. be able to. In other words, the slidable contact particle 10b moves so as to widen the interparticle region 12 in the radial direction from the central axis of the substrate 10a accompanying the thermal expansion of the substrate 10a.

  On the other hand, the thermal expansion of the sliding contact particle 10b due to an increase in temperature has an effect on other sliding contact particles 10b because there is an inter-particle region 12 in addition to the small thermal expansion coefficient of the sliding contact particle 10b. Does not reach.

  Therefore, it is not necessary to match the thermal expansion coefficients of the base body 10a and the sliding contact particle 10b, and the material selectivity of the base body 10a is widened. For example, the thermal expansion coefficient such as Co-based and Ni-based hard alloys is iron. Can be used.

  Further, the interparticle region 12 has a depth, that is, a difference in height between the surface of the base 10a and the particle tip of the sliding contact particle 10b (that is, the sliding contact surface 13) of 0.8 μm or more. For this reason, the slidable contact surface 13 in the present embodiment does not include the surface of the base 10a, and the slidable contact surface 13 is formed only from the slidable contact particles 10b. As a result, in the shaft / bearing structure 1 </ b> A including the shaft member 10 and the bearing member 11, when the shaft member 10 rotates, only the sliding particle 10 b comes into sliding contact with the bearing member 11. Here, since the friction coefficient of the diamond particles, the DLC particles, and the cubic boron nitride constituting the sliding contact particles 10b is low, the shaft member 10 is in a non-lubricating condition in which a lubricant such as water does not exist between the shaft member 10 and the bearing member 11. It can rotate smoothly even underneath. Furthermore, since the friction coefficient is low, the generation of heat due to friction is suppressed, and the durability of the material is improved. In addition, once water has passed through the shaft / bearing structure 1A, the water is stored in the interparticle region 12, so that when the shaft member 10 is rotated, the sliding particles 10b and the bearing member 11 are moved from the interparticle region 12 to each other. Water is appropriately supplied as a lubricant in the meantime, and lubricity is improved.

  More preferably, the depth of the region between the sliding particles is 1.0 μm or more. Further, the depth of the interparticle region 12 is preferably 50 μm or more so that more appropriate water can be stored even when the substrate is thermally expanded, and 150 μm or less in order to supply water more appropriately as a lubricant. It is preferable that

  Moreover, it is preferable that the surface density which is a ratio of the area which the sliding contact particle | grains 10b occupy when it sees from the perpendicular | vertical direction of the surface of the base | substrate 10a is 20 to 70%. Here, a large surface density means that the interval between the sliding contact particles 10b is narrow, and conversely, a small surface density means that the interval between the sliding contact particles 10b is wide. By setting the surface density to 20 to 70%, the slurry particles can easily escape to the inter-particle region 12. That is, the slurry particles that have entered between the shaft member 10 and the bearing member 11 are more likely to be sent to the interparticle region 12 than to be sandwiched between the sliding contact particle 10 b and the bearing member 11. Then, the slurry particles can be discharged to the outside of the shaft / bearing structure 1A through the interparticle region 12 formed on the entire outer surface of the substrate 10a. As a result, it is possible to suppress wear of the bearing member 11, which is the counterpart material, due to the engagement of the slurry particles between the sliding contact particles 10 b and the bearing member 11. When the surface density is less than 20%, since the sliding contact particles 10b forming the sliding contact surface 13 are few, the surface pressure on the bearing member 11 is increased, and the bearing member 11 is easily damaged. Further, when the surface density exceeds 70%, the inter-particle region 12 becomes narrow, and relatively large slurry particles cannot pass through, so that the biting of the slurry particles may increase. Further, when the surface density exceeds 70%, it becomes difficult to store water between the sliding contact particles, or the stored water is difficult to be discharged. Therefore, the surface density is more preferably 60%, and still more preferably 55% or less.

  Moreover, it is preferable that the average particle diameter of the sliding contact particle | grains 10b is 10 micrometers-500 micrometers. The average particle size is a value measured by a laser diffraction particle size distribution analyzer: Shimadzu Corporation, SALD-2100. When the average particle diameter is smaller than 10 μm, the force for holding the sliding contact particles 10b is small, so that the particles are easily dropped from the base 10a. Therefore, in order to further prevent dropping from the base 10a, the average particle diameter of the sliding contact particles 10b is preferably 40 μm or more, and more preferably 80 μm or more. When the average particle diameter is larger than 500 μm, conditions such as pressure applied at the time of manufacture increase, and a large amount of cost is required for equipment and the like, making it difficult to process the tip of the sliding contact particle 10b. Further, in order to more efficiently process the tip of the sliding contact particle, the average particle diameter is preferably 200 μm or less, and more preferably 150 μm or less.

<Fixing method of sliding contact particles>
In this embodiment, the sliding contact particles 10b can be fixed onto the outer surface of the substrate 10a by using electrodeposition or spark plasma sintering (hereinafter referred to as SPS). Each fixing method will be described below.

(Fixing method using electrodeposition)
A method of fixing sliding contact particles using electrodeposition in the present embodiment will be described with reference to FIG. FIG. 3 is a cross-sectional view showing a state in which the sliding contact particles 10b of the shaft member 10 are electrodeposited on the substrate 10a.

  The sliding contact particles 10b can be fixed on the surface of the substrate 10a by a known electrodeposition method. For example, the sliding contact particle 10b is adhered by disposing the powder of the sliding contact particle 10b on the surface of the base body 10a. Thereafter, the surface of the substrate 10a is nickel-plated by energizing in the nickel solution, and as a result, as shown in FIG. 3, the sliding contact particles 10b are embedded to some extent in the nickel-plated film 20, and on the substrate 10a. Fixed to. Alternatively, for example, the base body 10a whose surface other than the outer surface is masked is placed in a nickel plating solution containing the sliding contact particles 10b. At this time, the depth at which the sliding contact particles 10b are embedded in the nickel plating film 20 is preferably 50% or more of the average particle diameter. Thereafter, by supplying electricity in the nickel plating solution by an electrolytic method, as shown in FIG. 3, a nickel plating film 20 is applied to the outer surface of the substrate 10a, and the sliding contact particles 10b in the nickel plating solution are nickel-plated. It is embedded to some extent in the film 20 and fixed on the substrate 10a. That is, the nickel plating film 20 functions as a fixing member for fixing the sliding contact particles 10b. According to this method, it is not necessary to perform diamond sintering under high pressure conditions as in Patent Document 1, and the sliding contact particles 10b can be fixed on the substrate 10a under atmospheric pressure conditions. In addition, as a plating solution used for electrodeposition, a plating solution of another metal or alloy may be used. Further, by adjusting the concentration of the sliding contact particles 10b in the plating solution, the size of the inter-particle region 12 between the sliding contact particles 10b and the surface density of the sliding contact particles 10b can be adjusted.

(Fixing method 1 using SPS)
An example of a method for fixing the sliding contact particle 10b using SPS in the present embodiment will be described with reference to FIG. FIG. 4A is a diagram showing a flow when the sliding contact particle 10b is fixed on the base body 10a using SPS, and FIG. 4B is a view showing that the sliding contact particle 10b is fixed on the base body 10a by SPS. It is sectional drawing which shows the state.

  SPS is known as a method usually used for powder sintering and the like. SPS is a method that has the advantages of simultaneously pressing a sample to a high pressure, promoting bonding between particles by plasma formation or the like, and rapidly heating to a high temperature.

  First, the sliding contact particle powder layer 30 is placed on the substrate 10a, and then pressure molding is performed using an SPS device under conditions of, for example, 950 ° C. and 30 MPa. As a result, the sliding contact particles 10b are scattered in a thickness of one particle on the base body 10a after pressure molding. Other sliding contact particles 10b that are not held on the substrate 10a can be removed after the pressure is removed. Therefore, the other sliding contact particles 10b that are not held by the base body 10a can be reused.

  In addition, since it press-molds with the pressure lower than the pressure applied in the case of the diamond sintering of patent document 1, a manufacturing cost can be made low compared with the technique of patent document 1. FIG.

(Fixing method 2 using SPS)
Another example of the method for fixing the sliding contact particle 10b using SPS in the present embodiment will be described with reference to FIG.

  As shown in FIG. 5, first, a mixed powder of the sliding contact particles 10b and the hard metal powder is placed on the base 10a, and then pressure-molded using an SPS apparatus. The sliding contact particle-metal composite body 51 is formed on the substrate 10a by pressure molding using the SPS apparatus. Here, as the hard metal powder, for example, a cobalt alloy powder is used, but other alloys or metal powders can also be used.

  The slidable contact particle-metal composite 51 is formed by a slidable contact particle 10b that is slightly stuck and fixed to the outer surface of the substrate 10a, and a hard metal film 50 formed around the slidable contact particle 10b. That is, the hard metal film 50 functions as a fixing member for assisting in fixing the sliding contact particles 10b to the base body 10a. In the pressure molding by the SPS apparatus, a high pressure of several GPa as in the conventional Patent Document 1 is not necessary, and the pressure may be increased at a pressure of about 100 MPa at the highest. By this pressure forming, a bond is formed between the hard metal film 50 and the sliding contact particle 10b, and fixing of the sliding contact particle 10b on the base body 10a is promoted.

  According to this fixing method, the hard metal film 50 as a fixing member for fixing the sliding contact particle 10b to the base body 10a is formed in the interparticle region 12 which is a region between the sliding contact particles 10b. Further, if a material harder than the slurry particles is used as the hard metal film 50, even if the material of the base 10a is soft, the wear of the base 10a due to the slurry particles passing through the inter-particle region 12 can be prevented. That is, the base 10 a can be protected by the hard metal film 50. At this time, the depth from the tip of the sliding contact particle 10b to the upper end of the hard metal film 50 is preferably larger than the particle diameter of the slurry particles. In particular, when the pump is used at a place where a large amount of slurry particles are presumed to be mixed, if the depth is 30 μm or more, more preferably 50 μm or more, or the average particle size of the sliding contact particles 10b exceeds 100 μm, The average particle diameter of the contact particles 10b is preferably 40% or more.

  In this way, in the configuration in which the hard metal film 50 is formed in the interparticle region 12, the depth of the region between the sliding contact particles is such that the surface of the hard metal film 50 and the particle tip of the sliding contact particle 10b (that is, the sliding contact). This is the difference in height from the contact surface 13). This also applies to the fixing method 3 using SPS, which will be described below.

(Fixing method 3 using SPS)
Another example of the method for fixing the sliding contact particles 10b using SPS in this embodiment will be described with reference to FIG.

  FIG. 6 is a cross-sectional view showing a state where the hard metal powder layer 60 is placed on the substrate 10a and the sliding contact particle powder layer 30 is placed thereon.

  As shown in FIG. 6, first, the hard metal powder layer 60 is placed on the substrate 10a, and the sliding particle powder layer 30 is placed thereon. Here, as the hard metal powder, for example, a cobalt alloy powder can be used, but other alloys or metal powders can also be used.

  Thereafter, the hard metal powder layer 60 is consolidated by pressure molding using an SPS apparatus, and a hard metal film 50 is formed on the surface of the substrate 10a. At the same time, the sliding contact particle powder layer 30 is pressed against the hard metal film 50, and the sliding contact particles 10 b are slightly embedded in the hard metal film 50 and fixed. That is, the hard metal film 50 functions as a fixing member for fixing the sliding contact particle 10b to the base body 10a. At this time, the sliding contact particles 10b are scattered and fixed on the hard metal film 50 with a thickness of one particle.

  In the fixing method 2 using the SPS, the sliding contact particle-metal composite body 51 is formed, whereas in this method, the hard metal film 50 and the sliding contact particle 10b are separated on the base 10a. doing. Therefore, most of the slidable contact particles 10b forming the slidable contact particle powder layer 30 can be recovered and reused after pressure molding using the SPS device. Thereby, cost can be reduced.

<Processing of sliding contact particles>
A method for processing the sliding contact particles 10b fixed on the base body 10a in the present embodiment will be described below.

  Processing is performed so that the particle tips of the sliding contact particles 10b fixed on the substrate 10a by the above-described method are on the same circumference. That is, the distance from the rotation center axis of the base body 10a to the outermost particle tip is made equal so that the particle tip of the sliding contact particle 10b is on the same circumference. As this processing method, it is possible to use a method of shaving with a grindstone such as diamond or silicon carbide, or electrical discharge machining. A person skilled in the art may select an appropriate method for grinding a material having high hardness such as the sliding contact particle 10b in the present embodiment.

  When processing the particle tip of the sliding contact particle 10b, the sliding contact particle 10b can fall off from the base 10a during processing. At this time, the location where the sliding contact particle 10 b is dropped becomes a new interparticle region 12.

  In the case of (fixing method 2 using SPS) (fixing method 3 using SPS), the tip of the sliding contact particle 10b is processed so as to be on the same circumference with the axis of the shaft member 10 as the center. In addition, the hard metal film so that the difference in height between the hard metal film 50 existing in the interparticle region 12 which is the region between the sliding contact particles 10b and the tip of the sliding contact particle 10b is 0.8 μm or more. 50 is ground. Thereby, the sliding contact surface 13 is formed only from the sliding contact particle 10b. Further, since the hard metal film 50 covers the base 10a, if a hard material is used as the hard metal film 50, the base 10a may be worn by slurry particles even if a soft material such as stainless steel is used as the base 10a. Can be prevented.

[Embodiment 2]
The following will describe another embodiment of the present invention with reference to FIG. Configurations other than those described in the present embodiment are the same as those in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals, and explanation thereof is omitted.

  FIG. 7 is a cross-sectional view of the shaft member 10 in the present embodiment. As shown in FIG. 7, the shaft member 10 of the present embodiment has a sliding contact particle 10b and an interparticle region 12 between the sliding contact particles 10b on the outer surface of the substrate 10a than the sliding contact particles 10b. This is different from the first embodiment in that the hard particles 40 having a small particle diameter are fixed.

The hard particles 40 are, for example, silicon carbide or other highly hard particles. The hard particles 40 preferably have a hardness of Hv 1000 kg / mm ² or more. Further, the hard particles 40 are fixed to the interparticle region 12 between the sliding contact particles 10b. The hard particles 40 fixed to the interparticle region 12 can prevent the slurry particles and the like from damaging the substrate 10a.

  Note that the depth of the interparticle region 12 in the second embodiment is a difference in height between the tip of the hard particle 40 and the tip of the sliding contact particle 10b, and is 0.8 μm as in the first embodiment. That's it.

  Thus, by mixing the sliding particles 10b and the hard particles 40 and adjusting the mixing ratio or the particle size of the hard particles 40, the surface density of the sliding particles 10b fixed on the substrate 10a can be easily adjusted. It becomes possible to do.

  Here, the distance between the hard particles 40 is preferably 50 μm or less. Accordingly, it is possible to prevent slurry particles (for example, silica particles) having a particle size of about 50 μm from passing between the hard particles 40 and hitting the substrate 10a.

  In addition, when the hard particle 40 larger in size than the sliding contact particle 10b is fixed on the surface of the base 10a, the tip of the hard particle 40 becomes lower than the sliding contact particle 10b by 0.8 μm or more thereafter. Thus, the tips of the hard particles 40 may be processed. Thereby, the sliding contact surface 13 is comprised only by the sliding contact particle 10b, and the hard particle 40 can protect the base | substrate 10a from a slurry particle.

[Embodiment 3]
The following will describe still another embodiment of the present invention with reference to FIGS. 9A and 9B and FIGS. 10A and 10B. Configurations other than those described in the present embodiment are the same as those in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals, and explanation thereof is omitted.

<Configuration of sliding member (shaft member)>
FIG. 9A is a cross-sectional view of the shaft member 10 in the present embodiment. FIG. 9B is an enlarged view of a part of the shaft member 10 shown in FIG.

  As shown in FIGS. 9 (a) and 9 (b), the shaft member 10 of the present embodiment has a sliding contact particle 10b fixed on the outer surface of the substrate 10a, and a coating 10b2 at least at the tip. Yes. The coating 10b2 is made of a DLC (Diamond-like Carbon) film or a glassy carbon film. That is, the sliding contact particle 10b is composed of the coating target particle 10b1 and the coating 10b2, and at least the tip of the coating target particle 10b1 is covered with the coating 10b2. Therefore, the upper surface of the coating 10 b 2 is the sliding contact surface 13 of the shaft member 10. The coating target particle 10b1 includes at least one of diamond particles, diamond-like carbon particles, cubic boron nitride, and glassy carbon particles.

  The film thickness of the coating 10b2 is preferably 5 μm to 10 μm. Thus, the shaft member 10 of the present embodiment is different from the shaft member 10 of the first embodiment in that the sliding contact particle 10b is composed of the coating target particle 10b1 and the coating film 10b2.

  In the example shown in FIGS. 9A and 9B, the shaft member 10 has a coating 10b2 on which the exposed surface of the substrate 10a and the surface of the coating target particle 10b1 exposed from the substrate 10a are covered. Covered. Accordingly, the depth of the interparticle region 12 in this case is the difference between the height of the coating 10b2 covering the tip of the coating target particle 10b1 and the height of the upper surface of the coating 10b2 covering the upper surface of the substrate 10a.

  Moreover, since the particle | grains shown with the code | symbol 10c in FIG.9 (b) start use of the sliding contact particle 10b after manufacture of the sliding contact particle 10b, since a particle size is small and height is insufficient. Furthermore, it is a non-sliding contact particle that cannot be the sliding contact particle 10b. Such non-sliding contact particles 10c may occur when the sliding contact particles 10b are provided on the substrate 10a. The non-sliding contact particle 10 c can perform the same function as the hard particle 40.

<Method for Forming Sliding Surface of Sliding Particles Having a Film>
(First forming method)
FIG. 10A is a schematic view showing a cross section of the shaft member 10 showing a first method of forming the sliding contact surface 13 of the sliding contact particle 10b having the coating 10b2.

  In the first forming method, first, as described above, the tips of the respective particles to be coated 10b1 are present on the same circumference around the axis of the shaft member 10 when viewed from the axial direction of the shaft member 10. Thus, the coating target particles 10b1 are processed. Next, the coating film 10b2 is formed so that at least the tip surface of the coating target particle 10b1 is covered.

(Second forming method)
FIG. 10B is a schematic diagram showing a cross section of the shaft member 10, showing a second method of forming the sliding contact surface 13 of the sliding contact particle 10 b having the coating 10 b 2.

  In the second forming method, first, the coating 10b2 is formed so that at least the tip surface of each of the particles to be coated 10b1 is covered. Next, the tip of the sliding contact particle 10b, that is, the upper surface of the coating 10b2 covering the tip surface of the coating target particle 10b1 is centered on the axis of the shaft member 10 when viewed from the axial direction of the shaft member 10 as described above. The coating 10b2 is processed so as to exist on the same circumference.

(Method for forming DLC film)
The DLC film (coating 10b2) can be formed by coating the DLC film on the particles to be coated 10b1. In this technique, a technique using a vapor deposition technique using plasma in vacuum or atmospheric pressure, a technique of electrically depositing a carbon film from a liquid such as an organic solvent, and the like are known. At present, the coating method by vapor deposition using a vacuum apparatus is the mainstream.

The coating method of the DLC film by the vapor deposition method using a vacuum apparatus is roughly classified into a method using solid carbon as a carbon supply source and a method using a hydrocarbon-based raw material. As a method using solid carbon (graphite) as a carbon source, arc ion plating, non-equilibrium magnetron sputtering, and filtered arc ion plating are known. Further, as a method using a hydrocarbon gas (CH ₄ , C ₆ H ₆ , C ₂ H _2, etc.) as a carbon supply source, high-frequency plasma CVD, pulsed direct-current plasma CVD, ionization deposition, and plasma ion implantation / film formation It has been known.

  When a DLC film having a thickness of 5 μm to 10 μm is formed on the coating target particle 10b1 by the above-described non-equilibrium magnetron sputtering (unbalanced magnet sputtering method), the corners of the coating target particle 10b1 (sliding contact particle 10b) are coated. It was covered and rounded.

  As described above, in the shaft member 10 of the present embodiment, the sliding contact particle 10b is composed of the coating target particle 10b1 and the coating 10b2, and at least the tip of the coating target particle 10b1 is covered with the coating 10b2, and the upper surface of the coating 10b2 Is the sliding contact surface 13 of the shaft member 10.

Thereby, the corner | angular part of the front-end | tip of the slidable contact particle 10b, ie, the coating target particle 10b1, can be covered with the coating 10b2 so that the surface becomes a smooth surface, and the slidable contact surface of the shaft member 10 is made even smoother. Can do.
(Formation of glassy carbon film)
The glassy carbon film (coating 10b2) is obtained by applying a resin composition for glassy carbon containing a thermosetting resin as a main component to the coating target particles 10b1, curing, and then firing in an inert atmosphere or under vacuum. It can be formed by carbonization.

[Embodiment 4]
Still another embodiment of the present invention will be described below with reference to FIGS. 11A and 11B and FIGS. 10A and 10B. Configurations other than those described in the present embodiment are the same as those in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals, and explanation thereof is omitted.

<Configuration of sliding member (shaft member)>
FIG. 11A is a cross-sectional view of the shaft member 10 in the present embodiment. FIG. 11B is an enlarged view of the sliding contact particle 10b shown in FIG.

  As shown in FIGS. 11A and 11B, in the shaft member 10 of the present embodiment, the slidable contact particles 10b fixed on the outer surface of the base body 10a include the coating target particles 10b1, the DLC film, And a coating 10b2 made of a glassy carbon film. The coating target particle 10b1 includes at least one of diamond particles, diamond-like carbon particles, cubic boron nitride, and glassy carbon particles.

  The coating target particle 10b1 is exposed at the tip surface (sliding contact surface 13) on the same circumference centered on the axis of the recording shaft / bearing structure, and the coating 10b2 is around the tip surface of the coating target particle 10b1. The outer surface of the portion that covers and corresponds to the corner from the front end surface to the side surface of the coating target particle 10b1 is a curved surface.

  The film thickness of the coating 10b2 is preferably 5 μm to 10 μm. Thus, the shaft member 10 of the present embodiment is different from the shaft member 10 of the first embodiment in that the sliding contact particle 10b is composed of the coating target particle 10b1 and the coating film 10b2.

  In the example shown in FIG. 11A, the shaft member 10 has a coating 10b2 on the surface exposed from the substrate 10a excluding the exposed surface of the substrate 10a and the tip surface of the coating target particle 10b1. Covered. Therefore, the depth of the interparticle region 12 in this case is the difference between the height of the tip surface of the sliding contact particle 10b (that is, the coating target particle 10b1) and the height of the upper surface of the coating 10b2 that covers the upper surface of the substrate 10a.

<Method for Forming Sliding Surface of Sliding Particles Having a Film>
In the shaft member 10 of the present embodiment, the slidable contact particle 10b having the coating 10b2 can be formed as follows.

  First, the slidable contact particle 10b having the coating 10b2 on the tip surface is formed by the first forming method shown in FIG. 10 (a) or the second forming method shown in FIG. 10 (b). Next, the tip surface of the sliding contact particle 10b is processed so as to remove the coating 10b2 until the tip surface of the coating target particle 10b1 is exposed.

  When the slidable contact particle 10b having the coating 10b2 on the tip surface is formed by the second forming method, the tip surface of the coating target particle 10b1 is processed until the exposed tip surface of the coating target particle 10b1 becomes flat.

  As described above, in the shaft member 10 of the present embodiment, the sliding contact particle 10b includes the coating target particle 10b1 and the coating 10b2 made of a DLC film or a glassy carbon film. The tip surface (sliding contact surface 13) existing on the same circumference centering on the axis of the shaft / bearing structure is exposed, and the coating 10b2 covers the periphery of the tip surface of the coating target particle 10b1, and the coating target particle 10b1. The outer surface of the portion corresponding to the corner from the tip surface to the side surface is a curved surface.

  Thereby, the shaft member 10 is non-lubricated by using a sliding contact particle containing at least one of diamond particles, diamond-like carbon particles, cubic boron nitride and glassy carbon particles having a low friction coefficient. Effects such as smooth rotation under conditions and improved material durability can be reliably exhibited. Moreover, since the coating 10b2 covers the periphery of the tip surface of the coating target particle 10b1 and the outer surface of the portion corresponding to the corner from the tip surface to the side surface of the coating target particle 10b1 is a curved surface, the shaft member 10 is The smoothness of the sliding surface can be further improved.

[Embodiment 5]
The following will describe still another embodiment of the present invention with reference to FIGS. Note that configurations other than those described in the present embodiment are the same as those in the first embodiment. For convenience of explanation, members having the same functions as those shown in the drawings of the first embodiment are given the same reference numerals, and explanation thereof is omitted.

<Configuration of sliding member>
In the above embodiment, the case where the sliding member is a shaft member or a bearing member of a shaft / bearing structure has been described. However, the sliding member is not limited to the shaft member or the bearing member, that is, the shape is not particularly limited as long as it is a member that slides relative to the sliding member. Therefore, in this embodiment, a case where the sliding member is a flat plate member will be described as an example. The configuration of the sliding member described in the present embodiment is applicable to the sliding members of all other embodiments described above.

  FIG. 12 is a longitudinal sectional view showing a configuration of a sliding contact member according to still another embodiment of the present invention, in which the sliding member base portion includes only a base.

  As shown in FIG. 12, the sliding member 10 includes a flat substrate 10a serving as a sliding member base, and sliding contact particles 10b scattered and fixed on the outer surface of the substrate 10a.

  As is clear in other embodiments, the sliding contact particle 10b protrudes from the base 10a, is in sliding contact with the sliding member, and supports the sliding member with a load. The average height from the surface of the base (sliding member base) 10a to the tip of the sliding contact particle 10b is 0.8 μm or more. The sliding contact particle 10b has a hardness equal to or higher than that of silica sand. Silica sand is the main component of the earth and sand (slurry particles) described above. The average height may be 2.0 μm or more.

  The sliding contact particle 10b includes at least one or more of diamond particles, diamond-like carbon particles (hereinafter referred to as DLC particles), cubic boron nitride, and glassy carbon particles. Here, the diamond particles include diamond single crystal particles and particles obtained by pulverizing a diamond sintered body. The DLC particles include particles obtained by granulating DLC powder using a binder and particles obtained by pulverizing a sintered body of DLC powder.

  As the at least one kind of particles contained in the sliding contact particle 10b, in addition to the aforementioned diamond particles, diamond-like carbon particles, cubic boron nitride and glassy carbon particles, alumina particles, boron carbide particles, silicon carbide particles, Mention may be made of tungsten carbide particles, silicon nitride particles and molybdenum carbide particles. Alumina particles include single crystal and polycrystalline particles.

  FIG. 13 is a longitudinal section showing a configuration of a sliding contact member according to still another embodiment of the present invention, in which the sliding member base portion is composed of a base and a surface forming portion provided on the outer surface of the base. FIG.

  In the sliding member 10 shown in FIG. 13, the sliding member base portion 10e has a base 10a and a surface forming portion 10d provided on the outer surface of the base 10a. Therefore, in this sliding member 10, the average height from the surface of the sliding member base 10e to the tip of the sliding contact particle 10b is the average height from the surface of the surface forming portion 10d to the tip of the sliding contact particle 10b.

  The surface forming portion 10d includes the nickel plating film 20, the hard metal film 50 (see FIG. 5) shown in FIG. 3, a layer of hard particles 40 having a particle diameter smaller than the sliding contact particle 10b (see FIG. 7), or other Any film or formation. Therefore, the sliding member 10 includes the sliding member base 10e and the sliding contact particles 10b scattered and fixed on the outer surface of the sliding member base 10e.

  Other configurations, functions, advantages, and the like of the sliding member 10 of the present embodiment are the same as those of the sliding member 10 of the other embodiments described above.

[Deformation]
As another embodiment in which the depth of the region between the sliding contact particles 10b is 0.8 μm or more, the portion of the binder exposed on the surface in the diamond sintered body that is a sintered body of the diamond particles and the binder Only a form of grinding can be considered. In this case, the surface of the diamond sintered body is ground so that the difference in height between the binder and the diamond particles is 0.8 μm or more. For example, surface processing may be performed using an abrasive that is softer than diamond particles and harder than the binder. The block of the diamond sintered body thus ground may be attached to the surface of the sliding member facing the sliding member. The shape of the block may be, for example, a spherical shape or a prism shape having a curved surface corresponding to the sliding member only on one surface.

  Further, if the unevenness on the surface of the sliding member does not reach the region depth between the sliding contact particles 10b in the sliding member, not only the wear of the base of the sliding member is suppressed, but also the wear of the sliding member Therefore, in the present invention, the sliding member with higher slidability can be obtained by making the unevenness of the surface of the sliding member smaller than the region depth between the sliding contact particles 10b in the sliding member. Can be obtained. In the above, although it is an example of a diamond sintered compact, a diamond-like carbon sintered compact, a cubic boron nitride sintered compact, and a glassy carbon sintered compact can be used similarly.

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

[Example 1]
A graphite mold having an inner diameter of 30 mm is filled with 2 g of diamond particle powder having an average particle diameter of 40 μm on a hard cobalt alloy (for example, Co—Cr—Mo—B—Si alloy) of φ30 × 6.5 mmt, and 30 MPa by an SPS apparatus. Baked at 900 ° C. for 5 minutes. At the time of demolding, most of the diamond particle powder was in a powdery state, and only diamond particles having a thickness of 1 particle were bonded to the substrate. When viewed from the direction perpendicular to the surface of the substrate (hard cobalt alloy), the surface density, which is the ratio of the area occupied by the diamond particles, was 40%.

  Next, the diamond particles bonded to the surface of the substrate were ground to process the tips of the diamond particles. Thereby, a sliding contact surface, which is a circumferential surface around the axis of the substrate, was formed by the tips of the diamond particles. The depth of the region between the diamond particles, that is, the difference in height between the surface of the substrate and the tip of the diamond particle (that is, the sliding contact surface) was 1.0 μm.

Thereafter, a chip of 18 × 12 × 6 mmt (the test surface was a surface of 18 × 12) was produced from the processed substrate. The chip was subjected to a frictional wear test for 1 hour under the conditions of a silicon nitride ring of φ140 / 106 × 6 mmt, a surface pressure of 2 kg / cm ² , and a peripheral speed of 2 m / sec. At this time, the test was performed under the condition that there was no lubricant between the tip and the ring.

  In addition, the friction and wear test is measured by the weight change of the tip or ring. Since the chip includes the base and sliding contact particles, the frictional wear of both the base and sliding contact particles is measured.

[Example 2]
A single crystal diamond having an average particle diameter of 140 μm was electrodeposited with nickel on the surface of a 12 × 12 × 53 mm steel material. At this time, a fine diamond having a particle diameter of 0.5 μm is added in advance to the electrodeposition liquid used for nickel electrodeposition, and the fine diamond is mixed in the nickel plating film formed on the surface of the steel material. It was. When viewed from the vertical direction of the surface of the steel material, the surface density, which is the proportion of the area occupied by the single crystal diamond, was 20%.

  Next, the single crystal diamond particles having an average particle diameter of 140 μm fixed to the steel material surface by electrodeposition were ground to process the diamond particles at the same height. The depth of the region between the diamond particles, that is, the height difference between the surface of the steel material and the tip of the diamond particle (that is, the sliding contact surface) was 65 μm.

Thereafter, a chip of 18 × 12 × 6 mmt (the test surface is a surface of 18 × 12) was produced from the processed steel material. The chip was subjected to a frictional wear test for 1 hour under the conditions of a titanium carbide ring of φ140 / 106 × 6 mmt, a surface pressure of 2 kg / cm ² , and a peripheral speed of 2 m / sec. At this time, the test was performed under the condition that there was no lubricant between the tip and the ring.

Example 3
Electrodeposition under the same conditions as in Example 2 except that diamond-DLC particles having an average particle diameter of 30 μm in which diamond particles and DLC particles were mixed at a weight ratio of 1: 1 were used as the sliding contact particles. Nickel electrodeposition of crystal diamond) and the surface of the sliding particles were processed. The surface density of the sliding contact particles was 30%. Moreover, the depth of the area | region between diamond-DLC particle | grains, ie, the difference of the height of the steel material surface, and the front-end | tip (namely, sliding contact surface) of diamond-DLC particle | grains was 2.0 micrometers.

  Then, a frictional wear test was performed under the same conditions as in Example 2 except that a silicon nitride ring was used as the ring. At this time, the test was performed under the condition that there was no lubricant between the tip and the ring.

Example 4
Except that the depth of the region between the diamond particles, that is, the height difference between the surface of the substrate and the tip of the diamond particles (that is, the sliding contact surface) is 0.2 μm, the same as in Example 1, A tip for a frictional wear test was prepared and a frictional wear test was performed. At this time, the test was performed under the condition that there was no lubricant between the tip and the ring.

[Examples 5 to 8]
Diamond particles having an average particle diameter of 40 μm to 180 μm were used as the sliding contact particles, and electrodeposition (single crystal diamond nickel electrodeposition) and processing of the sliding contact particle surface were performed under the same conditions as in Example 2. The surface density of the sliding contact particles was 10% to 80%, and the depth of the region between the diamond particles was 2.0 μm to 80 μm. Examples 4 to 6 were subjected to a frictional wear test under the same conditions as in Example 2 using a silicon nitride ring and Example 7 using a titanium carbide ring. At this time, the test was performed under a condition in which a slurry liquid in which a solid material having high hardness and water were present was present between the tip and the ring. The slurry concentration was the concentration shown in Table 2 described later.

Example 9
Except that DLC particles having an average particle diameter of 80 μm were used as the sliding contact particles, the sliding contact particle bonding and the sliding contact particle surface processing were performed using the SPS device under the same conditions as in Example 1. . The surface density of the sliding contact particles was 60%, and the difference between the depth of the region between the DLC particles, that is, the height between the surface of the substrate and the tip of the DLC particles (that is, the sliding contact surface) was 50 μm.

  Then, a friction and wear test was performed under the same conditions as in Example 1. At this time, the test was performed under a condition in which a slurry liquid in which a solid material having high hardness and water were present was present between the tip and the ring.

Example 10
Electrodeposition (nickel electrodeposition of single crystal diamond) and the surface of the sliding contact particles under the same conditions as in Example 2 except that cubic boron nitride particles (CBN) having an average particle diameter of 460 μm were used as the sliding contact particles. Was processed. The surface density of the sliding contact particles was 30%. The depth of the region between the cubic boron nitride particles, that is, the difference in height between the surface of the steel material and the tip of the diamond-DLC particle (that is, the sliding contact surface) was 100 μm.

  Then, a frictional wear test was performed under the same conditions as in Example 2 except that a silicon nitride ring was used as the ring. At this time, the test was performed under a condition in which a slurry liquid in which a solid material having high hardness and water were present was present between the tip and the ring.

Example 11
Electrodeposition (nickel electrodeposition of single crystal diamond) and processing of the surface of the sliding contact particles were performed under the same conditions as in Example 1 except that glassy carbon particles having an average particle diameter of 60 μm were used as the sliding contact particles. It was. The surface density of the sliding contact particles was 50%.

  Except for using glassy carbon particles having an average particle diameter of 60 μm as the sliding contact particles, bonding of the sliding contact particles using the SPS device and processing of the surface of the sliding contact particles were performed under the same conditions as in Example 1. went. The surface density of the sliding contact particles was 50%, and the difference between the depth of the region between the glassy carbon particles, that is, the height between the surface of the substrate and the tip of the glassy carbon particles (that is, the sliding contact surface) was 20 μm. It was.

  Then, a friction and wear test was performed under the same conditions as in Example 1. At this time, the test was performed under a condition in which a slurry liquid in which a solid material having high hardness and water were present was present between the tip and the ring.

  Table 1 is a table showing various conditions and test results of the sliding members produced in Examples 1 to 4 and tested.

  As shown in Table 1, as in Examples 1 to 3, the tips of the sliding contact particles are on the same circumference around the axis of the substrate, and the depth of the region between the sliding contact particles is 0.8 μm. In the case described above, it was confirmed that a sliding member having good slidability and excellent wear resistance was obtained. In Example 4 in which the depth of the region between the sliding particles was 0.2 μm, which was shallower than 0.8 μm, the friction coefficient was slightly larger than in Example 3, but good results were obtained. .

  Table 2 is a table showing various conditions and test results of the sliding members manufactured and tested in Examples 2-3 and 5-8.

  As shown in Table 2, the sliding members prepared in Examples 2 to 3 and 5 to 8 had good sliding properties and excellent wear resistance even under conditions where the slurry liquid was present. However, when the surface density of the slidable contact particles fixed to the substrate surface was 10% or 80%, the wear amount of the chip was about 10 times larger than when the surface density was 20% to 70%. Therefore, it was confirmed that the surface density is preferably 20% to 70% in order to further improve the wear resistance.

  Table 3 is a table showing various conditions and test results of the sliding members manufactured in Example 9, Example 10 and Example 11 and tested.

  As shown in Table 3, the sliding member produced using DLC particles, cubic boron nitride particles (CBN) or glassy carbon particles as the sliding contact particles is the same as the sliding member produced using diamond particles. In addition, it was confirmed that even under conditions where the slurry liquid is present, the material has good sliding properties and excellent wear resistance.

[Confirmation of effect by the presence or absence of particle protrusion]
About the sliding member 10, the effect (friction coefficient) by the sliding contact particle 10b protruding from the surface of the sliding member base 10e (base | substrate 10a) was confirmed. The results are shown in Table 4.

The substrates of Example A and Comparative Example are cobalt alloys containing tungsten carbide particles. The tips and rings of the sliding members shown in Examples A to C were manufactured in the same manner as in Example 1. The test was performed under the same conditions as in Example 1. However, the contact pressure was 4.2 kg / cm ² .

  The average height is the average height from the surface of the sliding member base 10e (base 10a) to the tip of the sliding contact particle 10b. The comparative example is 0 (no protrusion), and Example A is 1.4 μm (with protrusion). ), Example B was 1.2 μm (with protrusions), and Example C was 1.2 μm (with protrusions). As a result, the friction coefficient was 0.58 in the comparative example (no protrusion), 0.2 in Example A, 0.23 in Example B, and 0.25 in Example C. .

  As shown in Table 4, the sliding member 10 having the protruding sliding contact particle 10b has a smaller coefficient of friction than the sliding member having no protruding sliding contact particle 10b, and the sliding member As a sliding member that slides relatively, it has been confirmed that it has a good function.

  INDUSTRIAL APPLICABILITY The present invention can be used for a prior standby operation pump that performs an operation under severe conditions for a shaft / bearing structure such as a prior operation in an anhydrous state and a drainage in a gas-liquid mixed state of slurry including earth and sand. .

1A Shaft / bearing structure 10 Shaft member 10a Base body 10b Sliding contact particle 10b1 Coating target particle 10b2 Coating 10c Non-sliding contact particle 10d Surface forming portion 10e Sliding member base 11 Bearing member 12 Interparticle region 13 Sliding surface 20 Nickel plating film 30 Sliding contact particle powder layer 40 Hard particle 50 Hard metal film 51 Sliding contact particle-metal composite body 60 Hard metal powder layer

Claims (17)

A sliding member that slides relative to the sliding member,
A sliding member base;
Scattering particles fixed on the surface of the sliding member base and slidably contacting the sliding member,
The sliding particles protrude from the surface of the sliding member base ,
The sliding member characterized in that the tip of the sliding contact particle has a surface that forms a sliding contact surface in sliding contact with the sliding member. A sliding member that slides relative to the sliding member,
A sliding member base;
Scattering particles fixed on the surface of the sliding member base and slidably contacting the sliding member,
The sliding particles protrude from the surface of the sliding member base,
The sliding member base comprises a base and non-sliding contact particles fixed to the outer surface of the base and having a particle size smaller than the sliding contact particles . A sliding member that slides relative to the sliding member,
A sliding member base;
Scattering particles fixed on the surface of the sliding member base and slidably contacting the sliding member,
The sliding contact particles protrude from the surface of the sliding member base,
A sliding member characterized in that the surface of the sliding member base has a hardness of Hv 600 kg / mm ² or more . A sliding member that slides relative to the sliding member,
A sliding member base;
Scattering particles fixed on the surface of the sliding member base and slidably contacting the sliding member,
The sliding particles protrude from the surface of the sliding member base,
The sliding member, wherein the sliding particles are electrodeposited and fixed on the sliding member base . A sliding member that slides relative to the sliding member,
A sliding member base;
Scattering particles fixed on the surface of the sliding member base and slidably contacting the sliding member,
The sliding particles protrude from the surface of the sliding member base,
The sliding contact particles are composed of particles to be coated and a coating, and the particles to be coated are at least partially coated with the coating,
The coating consists of a diamond-like carbon film or a glassy carbon film covering the periphery of the tip surface of the particles to be coated,
A sliding member, wherein an outer surface of the coating corresponding to a corner portion extending from the tip surface to a side surface is a curved surface . A sliding member that slides relative to the sliding member,
A sliding member base;
Scattering particles fixed on the surface of the sliding member base and slidably contacting the sliding member,
The sliding particles protrude from the surface of the sliding member base,
A sliding member, wherein the sliding contact particles have an average particle diameter of 40 μm to 200 μm . The sliding member according to any one of claims 1 to 5 , wherein the sliding contact particles have a hardness equal to or higher than that of silica sand. The slidable contact particles are diamond particles, diamond-like carbon particles, cubic boron nitride, glassy carbon particles, alumina particles, boron carbide particles, silicon carbide particles, tungsten carbide particles, silicon nitride particles, and molybdenum carbide particles. One or more types are included, The sliding member of any one of Claims 1-5, 7 characterized by the above-mentioned. The sliding member according to claim 6, wherein the sliding particles include at least one of diamond particles, diamond-like carbon particles, cubic boron nitride, and glassy carbon particles. The sliding member according to any one of claims 1 to 9, wherein an average height from a surface of the sliding member base to a tip of the sliding contact particle is 0.8 µm or more. The sliding member according to any one of claims 1 to 10, wherein the sliding member is load-supported by a plurality of the sliding contact particles. When viewed from the vertical direction of the surface of the sliding member base, claim 1-11 in which the surface density is the ratio of the area in which the sliding contact grains account is characterized in that 20 to 70% 1 The sliding member according to item. The sliding member according to any one of claims 1 to 12 , wherein the sliding member base includes a base and a metal film formed on a surface of the base. The sliding member according to any one of claims 1 to 13 , wherein the sliding member is ceramic or cermet. The sliding member according to claim 5 , wherein the coating film covers at least the tip of the particles to be coated and is made of a diamond-like carbon film or a glassy carbon film. Used for shaft / bearing structure with shaft and bearing,
The sliding member according to any one of claims 1 to 15, wherein a tip of the sliding contact particle is on the same circumference centering on an axis of the shaft / bearing structure.   A pump comprising the sliding member according to claim 1.

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