JP7252067B2 - Sliding material - Google Patents

Description

The present invention relates to a sliding member.

Reciprocating fluid machines and scroll fluid machines are generally used as fluid machines for compressing fluid such as air. For example, in a reciprocating fluid machine, a piston that reciprocates in a metal cylinder is attached with a piston ring as a sliding material that slides on the inner surface of the cylinder. Further, for example, in a scroll-type fluid machine, a tip seal is attached as a sliding material to the end of a metal fixed scroll or a rotating scroll that contacts and slides while rotating on the fixed scroll. ing.

As the sliding material, for example, a resin material represented by polytetrafluoroethylene (hereinafter referred to as PTFE) is used. For example, PTFE, which has high crystallinity and low shear strength, is easily peeled off at the micro level when sheared, and is transferred to a mating surface such as the inner surface of a cylinder. In order to enhance the effect of reducing friction and wear of sliding materials using PTFE as a base material, it is common to use composite resin materials containing various particles such as carbon particles, metal particles, and inorganic compound particles. .

Patent Document 1 discloses that in a scroll type fluid machine, a hard filler such as diatomaceous earth or alumina having a hardness higher than that of the tooth bottom surface is added to the sliding material, thereby realizing a long life without increasing the cost. A scroll fluid machine is disclosed.

JP 2011-179392

By using the method described in Patent Literature 1, the wear resistance of the sliding material is improved, thereby making it possible to dramatically improve the durability of the fluid machine. However, in recent years, the industry has come to demand further improvement in durability.

Wear resistance can be improved by using a hard filler having a hardness equal to or greater than the tooth bottom surface of Patent Document 1, but when the hard filler is discharged as abrasion powder, the abrasive action worsens wear. Sometimes.

The above hard fillers are often atomized metal particles, ceramic particles obtained by pulverizing minerals or the like, and carbon particles obtained by high-temperature firing of resin particles. As a hard filler material, Patent Document 1 uses ceramic particles such as diatomaceous earth and alumina. Carbon particles may be used as another example of the material of the hard filler.

In many cases, these particles are spherical or similar in shape, or irregularly shaped by mechanical comminution. For example, when PTFE is blended with hard fillers having these shapes and used as sliding materials for fluid machinery, the hard fillers may fall off from the sliding material during sliding due to weak adhesion to PTFE. there were. As a result, the above-described abrasive action is enhanced, and the problem of worsening wear has arisen.

When such abrasive wear occurs, there arises a problem that durability cannot be further improved. As a result, the wear durability of the sliding portion is lowered, and problems such as shortening of the maintenance cycle of the fluid machine and shortening of the service life have arisen.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sliding material that can improve wear resistance and extend the maintenance cycle.

A preferred example of the present invention is a sliding material having a resin material as a base material and particles dispersed in the resin material, the particles being dendrite-like.

Another preferred example of the present invention is a sliding material having a resin material as a base material and particles dispersed in the resin material, the particles being plate-shaped.

According to the present invention, it is possible to improve wear durability, extend the maintenance cycle, and extend the service life.

It is a sectional view showing a sliding part of an example. FIG. 3 is a schematic diagram showing the microstructure of dendrite-like particles. 1 is a cross-sectional view showing the overall configuration of a reciprocating fluid machine; FIG. 4 is an enlarged view of the configuration inside the cylinder of FIG. 3; FIG. 1 is a cross-sectional view showing the configuration of a scroll fluid machine; FIG. 6 is an enlarged view of a part of the fixed scroll and orbiting scroll of the scroll fluid machine shown in FIG. 5; FIG. FIG. 2 is a cross-sectional view showing the configuration of a scroll-type fluid machine provided with an Oldham's coupling; FIG. 8 is an exploded perspective view showing the casing, orbiting scroll and Oldham coupling of FIG. 7; 8 is an enlarged view of the Oldham coupling of FIG. 7; FIG. 1 is scanning electron microscope images of copper particles used in Example 1, Example 2, and Comparative Example 1. FIG. It is a figure which shows the structure of a friction test. It is a figure which shows the wear volume obtained by the friction test, and the experimental result of a coefficient of friction. It is a figure which shows the optical microscope image of the abrasion powder sampled by the friction test. 1 shows Table 1 for the components of Example 1, Example 2, and Comparative Example 1. FIG.

FIG. 1 is a diagram showing a sliding portion 10 provided in a fluid machine according to an embodiment. Examples of fluid machines include reciprocating fluid machines and scroll fluid machines. The overall configuration of the reciprocating fluid machine and the scroll fluid machine will be described later.

The sliding portion 10 has a metal member 11 and a sliding member 12 made of a composite resin material having a fluororesin as a base material. In the sliding portion 10 , the sliding member 12 slides in contact with the member 11 at the sliding interface 13 . Lubricating oil, grease, or the like may be supplied to the sliding interface 13 . However, when the fluid machine of the embodiment is used in an oil-less state without supplying a sufficient amount of lubricating oil or the like, or when it is used in an oil-free state without supplying any lubricating oil or the like, Effective.

In the example shown in FIG. 1, the member 11 has a surface treatment 11b formed on the surface of a metal material 11a as a base material. That is, in the example shown in FIG. 1, the sliding surface is formed by the surface treatment 11b, and the sliding material 12 is brought into contact with and slides on the surface treatment 11b. Although FIG. 1 shows an example in which the surface treatment 11b is formed on the surface of the metal material 11a, the surface treatment 11b may not necessarily be formed on the metal material 11a. , the metal material 11a may be exposed. That is, the metal surface of the member 11 may be formed of the metal forming the metal material 11a, or may be formed by the surface treatment 11b formed on the metal material 11a.

The composite resin material forming the sliding member 12 contains particles 12b in a base material 12a, which is a resin material. Details of the particles 12b will be described later. The sliding material 12 contains rod-like particles 12c in addition to the particles 12b described above. Examples of the rod-shaped particles 12c include carbon fibers, glass fibers, metal fibers, and ceramic fibers. Particles other than the particles 12b and rod-like particles 12c described above, for example, solid lubricants such as molybdenum disulfide may be blended.

As the metal material 11a forming the member 11, for example, light metals such as aluminum, magnesium, and silicon, and transition metals such as iron, chromium, nickel, molybdenum, titanium, and copper can be used. Specific examples of the metal material 11a include aluminum-based materials such as aluminum and aluminum alloys, iron-based materials such as iron and iron-nickel alloys, titanium-based materials such as titanium and titanium alloys, and copper and copper alloys. A copper-based material can be used. Among them, when an aluminum-based material is used, excellent wear resistance can be obtained. The aluminum-based material may contain, for example, a small amount of magnesium, silicon, or the like. Also, the iron-based material may contain, for example, chromium, nickel, molybdenum, or the like.

The surface treatment 11b formed on the surface of the metal material 11a refers to a natural oxide film naturally formed on the metal material 11a or an artificially applied surface coating. In the case of the natural oxide film, for example, when the metal material 11a is aluminum, it is aluminum oxide, when it is iron, it is iron oxide, and when it is copper, it is copper oxide.

In the case of surface coating, for example, it is applied by plating, physical vapor deposition (PVD), chemical vapor deposition (CVD), carburizing, etc. At least one of aluminum, phosphorus, chromium, iron, nickel and zinc Constructed of materials containing Examples of surface coatings containing such elements include alumite treatment, aluminum plating, nickel plating, nickel phosphorous plating, chrome plating, iron plating, and zinc plating.

As the base material 12a of the composite resin material forming the sliding member 12, a resin material including a fluororesin material can be used. At least one selected from the group consisting of PTFE, tetrafluoroethylene/perfluoroalkyl vinyl ether copolymer (PFA), tetrafluoroethylene/ethylene copolymer (ETFE), and polyvinylidene fluoride (PVDF) as an example of the fluororesin can be used. For example, two or more kinds of PTFE and other fluororesins may be mixed and used.

Examples of resin materials other than fluororesin include ultra-high molecular weight polyethylene (UHMWPE), polyetheretherketone (PEEK), polyamide (PA), polyimide (PI), polyphenylene sulfide (PPS), polyacetal (POM), and phenolic resin. etc., and modifications thereof. Two or more kinds of these resin materials may be mixed and used, or two or more kinds of these resin materials and the above fluororesin materials may be mixed and used.

As the particles 12b mixed with the composite resin material constituting the sliding member 12, dendrite-like (or dendritic) or plate-like (or flaky, scale-like, or flake-like) particles are used. A dendrite has a shape in which a plurality of branches extend from a single axis, and refers to elongated and branched shapes including rod-like, needle-like, columnar, and spindle-like shapes.

FIG. 2 is a diagram schematically showing a dendrite with rod-shaped branches. It has a configuration in which a plurality of branch portions 12d each having an elongated rod-like shape are connected to each other. More specifically, each branch is radially arranged and the ends are connected. The branches do not necessarily have to be extremely elongated, nor do they need to have sharply pointed ends.

The reason for using the dendrite-like or plate-like particles 12b will be described. For example, in the sliding material disclosed in Patent Document 1, an oxide-based material such as alumina particles or diatomaceous earth particles is added to the base material. Oxide-based materials are hard and effective in improving the wear resistance of sliding materials. These particles that have fallen off become abrasive particles that have a cutting action, which may increase wear.

Dendrite-like or plate-like particles have a larger surface area than particles having a general spherical shape or similar shape. When the surface area of the particles is large, the contact area with the base material is increased, so the adhesion is high, and the frequency of falling off due to shearing can be greatly reduced. Therefore, a sliding member made of a composite resin material in which dendrite-like or plate-like particles 12b are blended into a base material has high abrasion resistance.

An example of a material forming the dendrite-like particles used as the particles 12b is a metal material. For example, dendrite-like particles can be obtained by electrolyzing an aqueous solution containing metal ions to deposit dendrite-like particles.

An example of the material forming the plate-like particles used as the particles 12b is a metal material, which is obtained by crushing and flattening non-flat particles such as pulverized powder.

An example of the metal material forming the particles 12b is copper or a copper alloy. The manufacturing method and material of the particles shown here are examples, and materials such as ceramics and carbon can also be used as long as they have similar shapes.

In order to improve the wear resistance of the sliding material 12, the particle size of the particles 12b is not particularly limited, but is, for example, in the range of 10 nm to 300 μm as an approximate spherical particle size measured by a laser diffraction particle size distribution analyzer. It is suitable for use in

When manufacturing the composite resin material that constitutes the sliding member 12, the powder of the base material 12a, the particles 12b produced by the above-described method, the rod-like particles 12c, molybdenum disulfide, and other powders are uniformly mixed in a mixer. Then, the mixture is molded into an arbitrary shape by compression molding or injection molding to obtain a molding, and the molding is baked in an electric furnace or the like to obtain a composite resin material. Firing is performed by appropriately adjusting the temperature range according to the type of base material to be used.

In order to confirm the existence of the particles 12b in the sliding material 12, the surface of the sliding material 12 and the crushed material of the sliding material 12 are microscopically observed using an optical microscope or a scanning electron microscope (SEM). It can be easily confirmed by confirming the particle shape such as dendrite shape or plate shape. As another confirmation method, (a) by baking the sliding member 12, the base material 12a is thermally decomposed and disappeared, and the shape can be confirmed by observing the particles 12b remaining as a residue. (b) By immersing the sliding member 12 in an acidic aqueous solution, the metal particles forming the particles 12b are dissolved, and the shape of the particles 12b can be confirmed. Furthermore, (c) by using X-ray CT, the shape of the particles contained in the sliding member 12 can be directly confirmed.

FIG. 3 is a diagram showing the overall configuration of the reciprocating fluid machine 40. As shown in FIG. The reciprocating fluid machine 40 has a cylinder 41 and a piston 42 that reciprocates inside the cylinder 41 . A compression/expansion chamber 43 as a working space for compressing or expanding fluid is formed in the space defined by the piston 42 within the cylinder 41 .

As shown in FIG. 3, the upper end of the cylinder 41 is closed by a partition plate 44, and the partition plate 44 is provided with a suction port 44a and a discharge port 44b. The suction port 44a and the discharge port 44b are provided with a suction valve 44c and a discharge valve 44d, respectively, and pipes are connected to the suction valve 44c and the discharge valve 44d, respectively.

As shown in FIG. 3, the cylinder 41 is open on the lower end side and connected to the housing 45 at the lower end. A connecting rod 46 is connected to the piston 42 via a piston pin 46a. A motor 47 is accommodated in the housing 45 . The motor 47 is connected to the connecting rod 46 via a pulley 48 and a belt 49 wound between the pulleys 48 .

During operation of the reciprocating fluid machine 40 , the power of the motor 47 is transmitted to the piston 42 by the connecting rod 46 via the belt 49 and pulley 48 . By moving the piston 42 up and down, outside air is sucked into the compression/expansion chamber 43 through the suction port 44a, and the suction gas is compressed in the compression/expansion chamber 43. As shown in FIG. The compressed gas is discharged to the outside of the compression/expansion chamber 43 through the discharge port 44b and recovered by piping.

FIG. 4 is an enlarged view of the internal configuration of the cylinder 41 of the reciprocating fluid machine 40 shown in FIG. A piston ring 421 and a rider ring 422 are attached to the piston 42 , and the piston ring 421 and the rider ring 422 slide on the inner peripheral surface of the cylinder 41 as the piston 42 moves up and down. As a result, contact and galling between the piston 42 and the cylinder 41 can be prevented, and a smooth sliding state between the piston 42 and the cylinder 41 can be obtained.

The cylinder 41 corresponds to the member 11 in FIG. 1, and the piston ring 421 corresponds to the sliding member 12 in FIG. The piston 42 may be made of metal or resin. The cylinder 41 is made of metal using the metal material 11a (see FIG. 1) as a base material, and can be formed using the same materials as those described for the metal material 11a.

A film may be appropriately formed on the cylinder 41 by surface treatment 11b on the metal material 11a. For example, the surface of the metal material 11a may be used with a natural oxide film formed thereon, or may be subjected to alumite treatment, nickel plating, or the like. Note that the surface of the metal material 11a of the cylinder 41 does not have to be coated.

The piston ring 421 is made of the composite resin material described above. That is, the piston ring 421 is formed using a composite resin material in which the particles 12b and the rod-like particles 12c are blended with a resin base material. As with the piston ring 421, the rider ring 422 may also be formed using a composite resin material.

FIG. 5 is a cross-sectional view showing the configuration of the scroll fluid machine 50. As shown in FIG. 5, the scroll fluid machine 50 includes a casing 53 forming an outer shell of the scroll fluid machine 50, a drive shaft 54 rotatably provided in the casing 53, a fixed scroll 51 attached to the casing 53, and an orbiting scroll 52 that is rotatably provided on the crankshaft 54A of the drive shaft 54 .

The fixed scroll 51 has a fixed end plate 51a and a fixed scroll wrap 51b spirally formed on one main surface side of the fixed end plate 51a. The orbiting scroll 52 has an orbiting end plate 52a and an orbiting scroll wrap 52b spirally formed on one main surface side of the orbiting end plate 52a. The orbiting scroll 52 has a boss portion 52f projecting from the center of the back side of the orbiting end plate 52a.

The orbiting scrolls 52 are arranged to face each other so that the orbiting scroll wraps 52b and the fixed scroll wraps 51b are meshed with each other. Thereby, a compression/expansion chamber 55 is formed between the fixed scroll wrap 51b and the orbiting scroll wrap 52b as a working space for compressing or expanding fluid.

A suction port 56 is formed on the outer peripheral side of the fixed end plate 51 a of the fixed scroll 51 . The suction port 56 communicates with the outermost compression/expansion chamber 55 . A discharge port 57 is formed in the central portion of the fixed end plate 51a of the fixed scroll 51. As shown in FIG. The discharge port 57 opens into the innermost compression/expansion chamber 55 .

The drive shaft 54 is rotatably supported by the casing 53 via ball bearings 58 . One end side of the drive shaft 54 is connected to an electric motor or the like outside the casing 53, and the other end side of the drive shaft 54 extends into the casing 53 to become a crankshaft 54A. The axis of the crankshaft 54A is eccentric with respect to the axis of the drive shaft 54 by a predetermined dimension.

An annular thrust receiving portion 61 is provided on the inner circumference of the casing 53 on the orbiting scroll 52 side. A thrust plate 62 is provided between the thrust receiving portion 61 and the turning end plate 52a. The thrust plate 62 is formed as an annular plate made of a metal material such as iron. When the orbiting scroll 52 orbits, its surface slides against the orbiting end plate 52a, and the thrust direction acting on the orbiting scroll 52 mainly during the compression operation (direction separating the orbiting scroll 52 from the fixed scroll 51). The thrust plate 62 receives the load together with the thrust receiving portion 61 . This prevents galling and abnormal wear between the casing 53 and the turning end plate 52a.

An Oldham ring 63 is provided between the thrust receiving portion 61 and the turning end plate 52a at a position closer to the center than the thrust plate 62. As shown in FIG. The Oldham ring 63 prevents the rotation of the orbiting scroll 52 when the orbiting scroll 52 is rotationally driven by the drive shaft 54, and provides circular motion with a predetermined orbital radius by the crankshaft 54A.

When the drive shaft 54 is driven to rotate by an electric motor (not shown) or the like, the orbiting scroll 52 orbits with a predetermined orbital radius, and the external air sucked from the suction port 56 moves between the fixed scroll wrap 51b and the orbiting scroll wrap. 52b are sequentially compressed in a compression/expansion chamber 55 defined between them. This compressed air is discharged from the discharge port 57 of the fixed scroll 51 to an external air tank or the like.

FIG. 6 is an enlarged view of a part of the fixed scroll 51 and the orbiting scroll 52 of the scroll fluid machine 50 shown in FIG. A groove 51d is formed in the end face 51c of the stationary scroll wrap 51b on the opposite side to the orbiting end plate 52a, and a tip seal 591 is fitted in the groove 51d.

A groove 52d is also formed in the end face 52c of the orbiting scroll wrap 52b on the opposite side to the fixed end plate 51a, and a tip seal 592 is fitted in this groove 52d as well.

As the orbiting scroll 52 orbits, the tip seal 591 slides against the wrap bottom surface 52e of the orbiting end plate 52a, and the tip seal 592 slides against the wrap bottom surface 51e of the fixed end plate 51a. As a result, contact between the fixed scroll wrap 51b and the wrap bottom surface 52e of the orbiting end plate 52a and contact between the orbiting scroll wrap 52b and the wrap bottom surface 51e of the fixed end plate 51a can be prevented, and a smooth sliding state can be obtained. can be done.

6, a fixed scroll 51 and an orbiting scroll 52 correspond to the member 11 in FIG. 1, and a tip seal 591 and a tip seal 592 correspond to the sliding member 12 in FIG. The fixed scroll 51 and the orbiting scroll 52 are made of metal using the metal material 11a (see FIG. 1) as a base material, and can be formed using the same material as described for the metal material 11a. On the wrap bottom surface 51e of the fixed end plate 51a of the fixed scroll 51 and the side surface of the fixed scroll wrap 51b, a film such as a plating film may be appropriately formed by surface treatment of the metal material 11a.

The tip seal 591 and the tip seal 592 are made of a composite resin material. That is, the tip seal 591 and the tip seal 592 are formed using a composite resin material in which the particles 12b and the rod-like particles 12c are blended with the base material 12a.

Further, in the sliding portion between the thrust plate 62 and the swivel panel 52a, the surface of the thrust plate 62 or the surface of the swivel panel 52a forming the sliding surfaces thereof may be coated with the composite resin material described above. Also, in the above description, an example in which the thrust plate 62 is made of a metal material such as iron is shown, but the thrust plate 62 itself may be made of a composite resin material.

Further, in the above description, the thrust plate 62 and the Oldham ring 63 provided at a position closer to the center than the thrust plate 62 are used to prevent the orbiting scroll 52 from rotating. The embodiment can also be applied to a scroll type fluid machine using other anti-rotation mechanisms such as an auxiliary crank (not shown).

FIGS. 5 and 6 show the configuration of the scroll fluid machine 50 including the Oldham ring 63 as a mechanism for preventing the orbiting scroll 52 from rotating. 7 to 9 show the configuration of a scroll type fluid machine 70 having an Oldham's coupling 90 as an anti-rotation mechanism for the orbiting scroll.

FIG. 7 is a cross-sectional view showing the configuration of a scroll-type fluid machine 70 having an Oldham's coupling 90 as an anti-rotation mechanism for the orbiting scroll.
In FIG. 7, 71 is a fixed scroll, 72 is an orbiting scroll, 73 is a casing, and 74 is a drive shaft. The orbiting scroll 72 has an orbiting scroll main body 75 and a substantially disk-shaped rear plate 76 attached to the rear side of the orbiting scroll main body 75 .

The fixed scroll 71 is provided with a fixed scroll wrap 71b on the surface side of the fixed end plate 71a, and a radiator plate 71c on the back side of the fixed end plate 71a. The orbiting scroll main body 75 is provided with an orbiting scroll wrap 75b on the surface side of the orbiting end plate 75a so as to face the fixed scroll wrap 71b, and a radiator plate 75c on the back side of the orbiting end plate 75a.

The rear plate 76 is fixed to the tip of the heat radiating plate 75c of the orbiting scroll body 75 by bolts or the like, and a boss portion 76d protrudes in the axial direction from the central portion of the rear surface. Note that the basic configuration of the scroll fluid machine 70 is the same as the configuration shown in FIG. 5 except for the points described above. Therefore, the description of the parts common to FIG. 5 will be omitted.

FIG. 8 is an exploded perspective view showing the casing 73, orbiting scroll 72 and Oldham coupling 90. As shown in FIG. 9 is an enlarged view of the Oldham coupling 90 of FIG. In the scroll fluid machine 70 , an Oldham's coupling 90 as an anti-rotation mechanism is provided between the back plate 76 of the orbiting scroll 72 and the flange portion 77 of the casing 73 .

As shown in FIGS. 8 and 9, the Oldham coupling 90 includes X-axis guides 91, 91 extending in the X-axis direction, Y-axis guides 92, 92 extending in the Y-axis direction orthogonal to the X-axis direction, an X-axis guide 91, and It has a slider 93 in sliding contact with the Y-axis guide 92 and each sphere 94 arranged on the slider 93 .

Each of the X-axis guides 91, 91 and the Y-axis guides 92, 92 is formed in an elongated square plate shape. The X-axis guides 91, 91 are provided integrally with the sliding surface 77A of the flange portion 77 of the casing 73, and are spaced apart by a constant dimension in the Y-axis direction. The Y-axis guides 92, 92 are provided integrally with the sliding surface 76A of the rear plate 76, and are spaced apart by a constant dimension in the X-axis direction.

The slider 93 is formed in a substantially square flat plate shape, and side surfaces 93a, 93a are in sliding contact with the inner surfaces of the X-axis guides 91, 91, and side surfaces 93b, 93b are in sliding contact with the inner surfaces of the Y-axis guides 92, 92. It is worn as A relief hole 93c through which the boss portion 76d of the rear plate 76 penetrates is formed in the central portion of the slider 93, and through holes 93d, 93d, 93d, and 93d are formed in the four corners thereof. Balls 94, 94, 94, 94 are inserted into the through holes 93d.

The Oldham's coupling 90 prevents the rotation of the orbiting scroll 72 by slidingly displacing the slider 93 in the X-axis direction and the Y-axis direction, and gives the orbiting scroll 72 circular motion with a predetermined orbiting radius. function as a mechanism.

In a scroll-type fluid machine 70 shown in FIG. 7, when a drive shaft 74 is rotationally driven by an electric motor or the like (not shown), an orbiting scroll 72 orbits at a predetermined orbital radius, and external air sucked from a suction port 78 is rotated. Air is sequentially compressed in compression/expansion chambers 79 defined between fixed scroll wrap 71b and orbiting scroll wrap 75b. This compressed air is discharged from a discharge port 80 of the fixed scroll 71 through a discharge pipe 81 and stored in an external tank.

For example, when the X-axis guides 91, 91 and the Y-axis guides 92, 92 are made of metal and the slider 93 is made of resin, the region constituting the sliding surface of the slider 93 is formed of the composite resin material described above. may Also, the surface forming the sliding surface of the slider 93 may be coated with a composite resin material.

Further, when the X-axis guides 91, 91 and the Y-axis guides 92, 92 are made of metal, the surfaces of the X-axis guides 91, 91 and the Y-axis guides 92, 92 may be coated with a composite resin material. . Alternatively, the X-axis guides 91, 91 and the Y-axis guides 92, 92 may be made of a composite resin material, and the slider 93 may be made of metal.

In both the reciprocating fluid machines shown in FIGS. 3 and 4 and the scroll fluid machines shown in FIGS. A less dry gas may be used. That is, when compressing a gas with a low dew point and low humidity, such as high-purity nitrogen gas, wear of the sliding material whose base material is fluororesin is likely to worsen, shortening the maintenance cycle and service life of fluid machinery. It was easy.

The sliding member of the above-described embodiment can exhibit sufficient abrasion resistance regardless of the type of fluid to be compressed. Therefore, a fluid machine to which the sliding member of the embodiment is applied can be used for, for example, compressing dry gas.

Examples of dry gases include gases with a dew point of −30° C. or lower. Examples of dry gases include synthetic air, high-purity nitrogen gas, oxygen gas, helium gas, argon gas, and hydrogen gas.

In the above-described embodiment, the case where the sliding member 12 shown in FIG. 1 is applied to a fluid machine represented by a compressor has been described as an example. However, the sliding material 12 of the embodiment may be used in mechanical devices requiring solid lubricity, such as vacuum devices, printing devices, analytical devices, and space-related equipment, in addition to fluid machinery.

(Example 1)
The effect of improving the wear resistance of the sliding member 12 of the example will be shown below by experiments using the friction test method. In the following studies, copper particles were used as representative examples of the particles 12b having a dendrite-like or plate-like shape. Example 1 is a sliding material 12 having a base material 12a, copper particles 12b, and carbon fiber rod-like particles 12c.
The material of the copper particles is pure copper with a purity of 99.99%. Table 1 for the components of Example 1, Example 2 and Comparative Example is shown in FIG.

Example 1 is a sliding material containing dendritic copper particles. Dendrite-like copper particles are copper particles formed by electrolysis of an aqueous solution containing copper ions.

(Example 2)
Example 2 is a sliding material 12 having a base material 12a, copper particles 12b, and carbon fiber rod-like particles 12c. In Example 2, instead of the dendrite-like copper particles of Example 1, plate-like copper particles were added to the sliding material. Plate-like copper particles are copper particles that have been flattened by crushing pulverized copper powder.

Comparative Example 1 is a sliding material 12 having a base material 12a, spherical copper particles 12b, and carbon fiber rod-like particles 12c. Comparative Example 1 differs from Examples 1 and 2 in that it is a sliding material containing spherical copper particles. In Examples 1 and 2 and Comparative Example 1, PTFE was used as the base material 12a.

FIG. 10 shows SEM observation images of the copper particles blended in the composite resin materials of Example 1, Example 2, and Comparative Example 1, respectively. As shown in FIG. 10, it can be clearly seen that the copper particles of Example 1 are dendritic, the copper particles of Example 2 are tabular, and the copper particles of Comparative Example 1 are spherical.

The friction test was conducted with the configuration shown in FIG. The materials of Example 1, Example 2, and Comparative Example 1 shown in FIG. 14 were processed into block-shaped test pieces 31, and metal ring-shaped test pieces 32 were contacted and rotated. The metal ring-shaped test piece 32 is an aluminum alloy. Sulfuric acid alumite treatment was applied to the surface. As experimental conditions for the friction test, the contact pressure was controlled to 1 MPa, the speed to 2 m/s, and the temperature to 120° C., and sliding was performed for 15 hours.

FIG. 12 shows the steady-state value of the coefficient of friction and the wear volume of the block-shaped test piece 31 made of the composite resin material, which were obtained as a result of the friction test. The wear volume is represented by a bar graph, and the wear coefficient is plotted with circles. The wear volume was obtained by dividing the amount of mass reduction before and after the test by the density. Also, in order to facilitate understanding of the results, the wear volume is shown as a relative value when Comparative Example 1 is set to 100.

Both Example 1 and Example 2 exhibited a smaller amount of wear than Comparative Example 1. Especially in the case of Example 1, the amount of wear was the smallest. In addition, both Example 1 and Example 2 showed a smaller coefficient of friction than Comparative Example 1. Especially in the case of Example 2, the amount of wear was the smallest. Therefore, the friction and wear of the sliding material were less when dendrite-like or plate-like copper particles were blended than when spherical copper particles were used.

Next, the state of abrasion powder sampled after the friction test was observed with an optical microscope. 13A and 13B are diagrams showing optical microscopic images of abrasion powder collected in each case of Example 1, Example 2, and Comparative Example 1. FIG. In Comparative Example 1, copper particles dropped from the surface of the composite resin material were observed, whereas in Examples 1 and 2, no removed copper particles were observed.

As is clear from the results of the friction test and the optical microscope observation of the abrasion powder described above, the sliding material 12 according to the embodiment has a dendrite-like or plate-like shape contained in the sliding material 12 when sliding against the member 11 . shaped copper particles do not fall off. Therefore, the generation of abrasive particles can be suppressed, and as a result, the wear durability of the sliding material 12 itself can be improved.

Therefore, by applying this sliding member 12 to, for example, the piston ring of a reciprocating fluid machine or the tip seal of a scroll fluid machine, the wear durability of the piston ring or the tip seal can be enhanced, and the replacement life of these parts can be extended. become longer. Therefore, the maintenance cycle and life of the reciprocating fluid machine and the scroll fluid machine can be extended.

DESCRIPTION OF SYMBOLS 10... Sliding part, 11... Member, 11a... Metal material, 11b... Surface treatment, 12... Sliding material, 12a... Base material, 12b... Particles

Claims (8)

a resin material as a base material;
Having copper particles and carbon fiber rod-shaped particles dispersed in the resin material,
The copper particles are
A sliding material characterized by being dendrite-shaped or plate-shaped . In the sliding material according to claim 1,
The resin material is
A sliding material characterized by being a fluororesin material. The sliding material according to claim 1 or claim 2 ,
A fluid machine, wherein the fluid machine is disposed in a sliding portion of the fluid machine that fluctuates the pressure of the fluid. 4. A fluid machine according to claim 3 , wherein said sliding material is used as a piston ring, a rider ring, a tip seal, or a slider. In the sliding material according to claim 1,
A fluid machine , wherein the copper particles are made of pure copper . A method for manufacturing a sliding material having a resin material as a base material and particles dispersed in the resin material, the method comprising:
Electrolyze an aqueous solution containing copper ions,
Dendrite-like copper particles are deposited by the electrolysis,
The copper particles, the rod-shaped particles of carbon fiber, and the powder of the resin material are mixed to form a mixture,
Molding the mixture into a molding,
A method for producing a sliding material, characterized by firing the molding. A method for manufacturing a sliding material having a resin material as a base material and particles dispersed in the resin material, the method comprising:
Create plate-shaped copper particles by flattening ,
The copper particles, the rod-shaped particles of carbon fiber, and the powder of the resin material are mixed to form a mixture,
Molding the mixture into a molding,
A method for producing a sliding material, characterized by firing the molding. In the method for manufacturing a sliding member according to claim 6 or 7,
A method for producing a sliding material , wherein the mixture contains molybdenum disulfide .

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