JP2002012903A - Porous backing material, method for production thereof, double-layered sliding member, and its production method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing a porous backing material in which a substrate and a porous sintered layer are strongly bonded to each other, and the effect of anchoring on a resin layer is high. SOLUTION: A bronze powder layer 24 in which its spherical powders B and irregular powders I are mixed with each other is formed on a steel plate 20, and they are vibrated. By this vibration, the irregular powders I gather approximately above the spherical powders B to cover them, while the spherical powders B are gathered on the surface of the steel plate 20 passing through between the irregular powders I. The bronze powders layer 24 in such a state is sintered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a porous substrate having a porous sintered layer formed on a substrate such as a steel plate, a method for manufacturing the same, and a resin layer formed on the porous sintered layer of the porous substrate. The present invention relates to a multi-layer sliding member filled (impregnated) and a method for producing the same.

[0002]

2. Description of the Related Art Conventionally, a multi-layer sliding member such as a so-called dry bearing in which a porous base material is filled with a resin is known (JP-B-31-2452, JP-B-39-39).
16950, Japanese Patent Publication No. 41-1868, Japanese Patent Publication No. 1-2486, and Japanese Patent Publication No. 7-58095). The porous substrate is obtained by forming a porous metal sintered layer on a substrate such as a steel plate. The porous metal sintered layer is filled and coated with a fluororesin such as polytetrafluoroethylene resin (hereinafter referred to as "PTFE") to form a resin layer, whereby a multi-layer sliding member is manufactured. Further, a multi-layer sliding member in which a synthetic resin layer in which a filler is mixed in PTFE is formed is also known. Furthermore, P
A multi-layer sliding member using a polyacetal resin in place of TFE is also known (see Japanese Patent Publication No. 49-44597).

The above-mentioned multi-layer sliding member is often used in the form of a so-called wound bush which is wound in a cylindrical shape with the resin layer inside, rather than in the form of a flat plate. Such a multi-layer sliding member has an advantage that load resistance can be greatly improved as compared with a sliding member made of a synthetic resin alone. For this reason, the multi-layer sliding member has been widely used in various applications.

[0004]

Incidentally, the sliding performance of the above-mentioned multilayer sliding member is influenced by the sliding characteristics of the synthetic resin or the synthetic resin composition filled and coated in the porous metal sintered layer. . When the sliding characteristics of a synthetic resin or the like are good, the sliding performance of the multilayer sliding member is also good.

[0005] The sliding performance of the multilayer sliding member is also affected by the quality of the porous metal sintered layer formed on the substrate. Factors that determine the quality of the porous metal sintered layer include: (1) the form of the metal powder forming the porous metal sintered layer; (2) the bonding strength between the porous metal sintered layer and the substrate; The degree of the anchoring effect (anchor effect) of the porous metal sintered layer on resin and the like is given. Here, the anchoring effect refers to a force by which the porous metal sintered layer can fix (do not peel or adhere) the resin layer filled and coated on the porous metal sintered layer.

[0006] The above factors will be discussed in more detail.

Heretofore, as a metal powder for forming a porous metal sintered layer, a metal powder in which a large number of spherical or irregular (eg, square) particles are collected (constituted) has been used. ing.

When a powder composed of a large number of spherical particles is used as the metal powder, the porous metal sintered layer obtained by sintering the powder is strongly bonded to the substrate. On the other hand, the porous metal sintered layer in which a large number of spherical particles are sintered has a problem that the anchoring effect is low and the synthetic resin layer is easily separated from the porous metal sintered layer.

On the other hand, when a powder composed of a large number of irregularly shaped particles is used as the metal powder, the anchor effect is high in a porous metal sintered layer in which this powder is sintered. On the other hand, there is a problem that the porous metal sintered layer in which many irregularly shaped particles are sintered is not strongly bonded to the substrate.

In view of the above circumstances, the present invention provides a porous substrate having a substrate and a porous sintered layer that are strongly bonded and having a high anchoring effect on a resin layer, a method of manufacturing the same, and a method of manufacturing the substrate and the porous sintered layer. It is an object of the present invention to provide a multilayer sliding member having high peel strength (high anchoring effect) by strongly bonding and also strongly bonding a resin layer to a porous sintered layer, and a method of manufacturing the same.

[0011]

To achieve the above object, a porous substrate of the present invention comprises (1) a substrate having a predetermined thickness;
(2) a first sintered layer uniformly covering the surface of the substrate;
(3) Second sintering covering the first sintered layer continuously from the first sintered layer, in which a large number of irregularly shaped particles are bonded to each other to form a large number of voids therein. And a layer.

Here, (4) the substrate may be made of steel.

(5) The first and second sintered layers may be made of bronze.

(6) The bronze has a composition comprising 9 wt% to 12 wt% of tin, 0.01 wt% to 0.50 wt% of phosphorus, and the balance copper. Is also good.

Further, a method for producing a porous substrate according to the present invention for achieving the above object is a method for producing a porous substrate in which a porous sintered layer is formed on a surface of a substrate having a predetermined thickness. In the method for producing a base material, (7) a powder layer forming step of forming a powder layer in which a large number of spherical particles and a large number of irregularly shaped particles are mixed on the surface of the substrate; and (8) forming a powder layer on the surface of the substrate. And (9) a sintering step of sintering the powder layer formed on the surface of the substrate after the vibration step is completed or together with the vibration step. It is characterized by the following.

Here, (10) the powder layer forming step comprises:
The step of forming the powder layer on the surface of a steel substrate may be performed.

(11) The powder layer forming step may be a step of forming a powder layer in which the spherical particles made of bronze and the irregular particles are mixed on the surface of the substrate.

Further, (12) the powder layer forming step comprises:
The above-mentioned spherical particles and the above-mentioned irregular-shaped particles made of 9% by weight or more and 12% by weight or less of tin, 0.01% by weight or more and 0.50% by weight or less of phosphorus, and the balance made of bronze having a composition of copper are mixed. Forming a powder layer on the surface of the substrate.

(13) In the powder layer forming step, the powder layer in which the large number of spherical particles having an average particle size smaller than the average particle size of the large number of irregularly shaped particles are mixed is formed on the surface of the substrate. It may be a forming step.

(14) In the powder layer forming step, (14-1) all particles comprising the large number of spherical particles and the large number of irregularly shaped particles pass through 60 mesh, Moreover, it passes through (14-2) 250 mesh and has an apparent density of 3.6 g / cm ³ or more and 4.2 g / cm ³ or less, and 30% by weight or more and 50% by weight or less of all the particles. And (14-3) passing through 100 mesh but not passing through 200 mesh, and having an apparent density of 3.
The powder layer is mixed with irregularly shaped particles of 1 g / cm ³ or more and 3.5 g / cm ³ or less and present in an amount of 35% by weight or more and 50% by weight or less of all the particles. It may be a step of forming on the surface of the substrate.

(15) The sintering step is performed in a heating furnace adjusted to a neutral atmosphere or a reducing atmosphere at a temperature in the range of 850 ° C. to 950 ° C. for 30 minutes to 60 minutes. May be a process of sintering only for the time.

According to another aspect of the present invention, there is provided a multi-layer sliding member for achieving the above object, comprising: (16) a porous substrate described in any one of claims 1 to 4; A) a resin layer filled and coated on the second sintered layer of the porous base material.

Here, (18) the resin layer may be made of a fluororesin.

Further, in order to achieve the above object, a method for manufacturing a multilayer sliding member according to the present invention comprises a porous base material having a porous sintered layer formed on the surface of a substrate having a predetermined thickness; The method for manufacturing a multilayer sliding member for manufacturing a multilayer sliding member having a resin layer filled and coated on a porous sintered layer, (19) The method according to any one of claims 5 to 11. And (20) forming a second sintered layer formed by sintering a large number of irregularly shaped particles while plastically deforming the second sintered layer. A resin layer forming step of forming a resin layer by filling and covering with a resin.

Here, the term "spherical particles" refers to particles whose overall shape is spherical. The irregularly shaped particles refer to particles having a shape other than a spherical shape, and include, for example, a star shape, a tree shape, and a square shape.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a schematic diagram showing a schematic configuration of a manufacturing apparatus for manufacturing a porous substrate. FIG. 2 is a cross-sectional view schematically showing the powder immediately after being sprayed on the steel plate. FIG. 3 is a cross-sectional view schematically showing a state after the steel sheet and the powder of FIG. 2 are vibrated. FIG. 4 is a cross-sectional view schematically showing a porous substrate obtained by sintering the powder shown in FIG.

The porous substrate manufacturing apparatus 10 is provided with a leveler 12 for correcting undulations and the like of the steel sheet 20 while pulling out and transporting the steel sheet 20 wound in a hoop shape from one end thereof. As the steel plate 20, a cold rolled steel plate or a strip (JIS G3141) having a plate thickness of about 0.5 mm to 2 mm is used.

The steel plate 20 is straightened by the leveler 12 while being conveyed in the direction of arrow A (conveying direction). A hopper 14 in which bronze powder 22 is stored is disposed slightly downstream of the leveler 12 in the transport direction.
The bronze powder 22 stored in the hopper 14 is supplied (sprayed) to the surface of the steel plate 20 that has passed through the leveler 12.
At the lower end of the hopper 14, a scraping plate 16 for smoothing the bronze powder 22 supplied to the surface of the steel plate 20 is fixed. The bronze powder 22 that has passed through the scraping plate 16 is smoothed,
As a result, a bronze powder layer 24 having a uniform thickness is formed on the surface of the steel plate 20. The steps so far are an example of the powder layer forming step according to the present invention.

Further, a sintering furnace 18 (an example of a heating furnace according to the present invention) is disposed downstream of the hopper 14 in the transport direction. The sintering furnace 18 has a known structure.

As the bronze powder 22, a bronze powder having a particle size distribution (%) shown in Table 1 is used.

[0032]

[Table 1] In Table 1, the symbol "-" added before the numerical value of the mesh
Indicates that particles constituting the powder pass through the mesh of the numerical value. On the other hand, the sign “+” added before the numerical value of the mesh indicates that the particles constituting the powder do not pass (do not pass) through the mesh of the numerical value. Therefore, for example, a particle size of +60 mesh means a particle size that cannot pass through 60 mesh.

In this embodiment, as shown in Table 1, all the particles constituting the bronze powder have a particle size of -60 mesh. Of all these particles, the proportion of particles having a particle size of −100 to +145 mesh (meaning from −100 mesh to +145 mesh, the same applies hereinafter) and −145 to +200 mesh is 35% by weight to 50% by weight. Within the following range. Further, the ratio of particles having a particle size of -250 to +350 mesh and -350 mesh is in the range of 30% by weight or more and 50% by weight or less.

As a result, all the particles consisting of a large number of spherical particles and a large number of irregularly shaped particles are particles passing through 60 mesh. Moreover, the particles passing through the 250 mesh are spherical particles having an apparent density of 3.6 g / cm ³ or more and 4.2 g / cm ³ or less, and 30% to 50% by weight of all the above particles. It is present in an amount within the range. On the other hand, particles that pass through 100 mesh but do not pass through 200 mesh are irregularly shaped particles whose apparent density is not less than 3.1 g / cm ^{3 and not} more than 3.5 g / cm ³ , and 35% of all the above particles. It is present in an amount in the range of greater than or equal to 50% by weight.

As described above, bronze powder in which a large number of two types of bronze particles having a particle size peak at two places of -100 to +200 mesh and -250 mesh are dispersed on the surface of the steel plate 20 to have a uniform thickness. A bronze powder layer 24 is formed on the surface of the steel plate 20. In the bronze powder layer 24 immediately after passing through the scraper 16, as shown in FIG.
Irregularly shaped particles I having a particle size of 0 mesh;
This is a state in which spherical particles B having a mesh size are mixed.

While the steel plate 20 is being conveyed in the direction of arrow A, vibration of the leveler 12 and the like is transmitted to the steel plate 20. Therefore, the bronze powder layer 24 vibrates together with the steel plate 20. Due to this vibration, as shown in FIG.
Pass between the irregularly shaped particles I and gather on the surface of the steel plate 20, while the irregularly shaped particles I gather almost on the spherical particles B and cover the spherical particles B. In this manner, the fact that the spherical particles B and the irregularly shaped particles I are biased in the bronze powder layer 24 is referred to as a particle size segregation in the bronze powder layer 24. The step of vibrating the bronze powder layer 24 as described above is an example of the vibration step according to the present invention.

As shown in FIG. 1, the steel sheet 20 having the surface on which the bronze powder layer 24 having the grain size segregation is formed is placed in a sintering furnace 18.
It is carried in. The sintering furnace 18 is adjusted to a neutral atmosphere or a reducing atmosphere. The steel sheet 20 and the bronze powder layer 24 carried into the sintering furnace 18 are sintered at a temperature in the range of 850 ° C. to 950 ° C. for a time in the range of 30 minutes to 60 minutes. This sintering step is an example of the sintering step according to the present invention.

In this sintering step, a large number of spherical particles B distributed on the surface of the steel sheet 20 generate a liquid phase and the densification proceeds rapidly, and as shown in FIG. A covering layer 26 (which is an example of the first sintered layer according to the present invention) is formed so as to cover.

On the other hand, in the sintering step, the irregularly shaped particles I gathered on the spherical particles B also generate a liquid phase. However, the irregularly shaped particles I are continuously bonded to the bonding layer 26 while keeping the irregular outer shape without significantly changing the shape. Therefore, as shown in FIG. 4, a porous layer 28 (which is an example of the second sintered layer according to the present invention) is formed. A large number of voids 28a are formed in the porous layer 28.

As described above, the porous substrate 30 having both the steel plate 20 and the bonding layer 26 covering the surface thereof, and the porous layer 28 continuously covering the bonding layer 26 from the bonding layer 26
Is manufactured. Since the bonding layer 26 uniformly covers the surface of the steel plate 20, the bonding strength between the two is high.

As described above, a large number of voids 28a are formed in the porous layer 28 of the porous substrate 30, and a large number of irregularities are formed. As a result, the specific surface area of the porous layer 28 is increased,
When the porous layer 28 is filled with the synthetic resin, the synthetic resin is in a state of being caught by the above-mentioned unevenness. As a result,
Since the so-called anchor effect (anchor effect) is enhanced, the synthetic resin is less likely to peel from the porous layer 28, and the peel strength is increased.

[0042]

Embodiments of the present invention will be described below.

<Examples 1 and 2> The steel plate 20 (FIG. 1)
As a reference, two cold-rolled steel sheets having a width of 180 mm and a thickness of 0.75 mm were prepared. Using a porous substrate manufacturing apparatus 10 shown in FIG. 1, two kinds of bronze particles having a particle size distribution shown in Table 2 (Examples 1 and 2) 2) bronze powder was sprayed to a uniform thickness to form a bronze powder layer having a thickness of 0.3 mm. In Examples 1 and 2, a bronze powder composed of 10% by weight of tin, 0.05% by weight of phosphorus, and the balance copper was used as the bronze powder.

[0044]

[Table 2] In Table 2, particles having a particle size of −60 mesh to +250 mesh are irregularly shaped particles. Also, -25
Particles having a particle size of 0 mesh are spherical particles.

The bronze powder layer 24 formed on the surface of the cold-rolled steel sheet was vibrated as described with reference to FIG. Due to this vibration, a large number of spherical particles of -250 mesh passed between a large number of irregularly shaped particles, and moved mainly toward the surface of the cold-rolled steel sheet and gathered on this surface. on the other hand,
The irregularly shaped particles gathered almost over the spherical particles and covered the spherical particles. This resulted in particle size segregation as shown in FIG.

The cold-rolled steel sheet having the surface on which the bronze powder layer having the grain size segregation was formed was carried into a sintering furnace 18 (see FIG. 1) adjusted to a reducing atmosphere. The cold-rolled steel sheet and the bronze powder layer carried into the sintering furnace 18 were sintered at 900 ° C. for 30 minutes.

In this sintering step, a large number of spherical particles distributed on the surface of the cold-rolled steel sheet generate a liquid phase, and the numerous spherical particles are bonded together and bonded to the surface of the cold-rolled steel sheet. Layer 26 (see FIG. 4) was formed. On the other hand, in the sintering process, a large number of irregularly shaped particles also generate a liquid phase, but these irregularly shaped particles have a large number of irregularly shaped particles while maintaining an irregular outer shape without significantly changing its shape. The particles were bonded together and continuously bonded to the bonding layer 26, and some of the irregularly shaped particles were also bonded to the surface of the cold-rolled steel sheet. Thereby, for example, as shown in FIG. 4, a porous layer 28 was formed. A large number of voids 28a are formed in the porous layer 28.

As described above, a porous substrate having the cold-rolled steel sheet and the joining layer 26 covering the surface thereof, and the porous layer 28 continuously covering the joining layer 26 from the joining layer 26 is manufactured. Was. Note that, as described above, the bonding layer 26
Bronze powder mainly composed of a large number of spherical particles of −250 mesh is sintered, and the porous layer 28 is mainly composed of −6 mesh.
Bronze powder composed of a large number of irregularly shaped particles having a size of 0 mesh to +250 mesh is sintered. <Comparative Example> A cold-rolled steel sheet having a width of 180 mm and a thickness of 0.75 mm was prepared in the same manner as in the above-described embodiment. On the surface of the cold-rolled steel sheet, a bronze powder having a particle size distribution shown in Table 3 and having a large number of horn-like particles aggregated was applied to the surface of the cold-rolled steel sheet in a thickness of 0.3 mm in the same manner as in the above example. Then, a bronze powder layer was formed.

[0049]

[Table 3] The cold-rolled steel sheet having the bronze powder layer formed on its surface is carried into a sintering furnace 18 (see FIG. 1) adjusted to a reducing atmosphere,
Sintered at 900 ° C for 30 minutes. Thereby, as shown in FIG. 5, a porous sintered layer 42 formed by sintering bronze powder and a cold-rolled steel sheet having the porous sintered layer 42 integrally formed on the surface thereof are formed. The quality substrate 40 was obtained. As shown schematically in FIG. 5, a large number of voids 42a were formed in the porous sintered layer 42. However, the gap 2 shown in FIG.
As compared with 8a, the space of the gap 42a is wider and there are few irregularities.

The porous sintered layers 28, 40 of the porous substrates 30, 40 obtained in Examples 1 and 2 and Comparative Example described above,
42 was filled and coated with a synthetic resin composition to form a synthetic resin layer. Thereafter, the peel strength of the synthetic resin layer was measured.
The measurement results and the like will be described. <Preparation of Synthetic Resin Composition and Synthetic Resin Layer> A synthetic resin composition was prepared by uniformly mixing 20% by weight of a polyimide resin powder, 1% by weight of a graphite powder, and the remainder of a polytetrafluoroethylene resin powder with a Henschel mixer. A petroleum-based solvent was added to this synthetic resin composition to prepare a wet resin composition. This wet resin composition was supplied to the porous sintered layers 28 and 42 of the porous substrates 30 and 40 obtained in the above Examples 1 and 2 and Comparative Example. Thereafter, the porous sintered layers 28 and 42 to which the wet resin composition was supplied were rolled by a known roller. As a result, the porous resin layers 28 and 42 were filled and covered with the wet resin composition. Then, the porous sintered layers 28 and 42 were placed in a hot-air drying furnace heated to a temperature of 200 ° C. for 5 minutes.
The solvent in the wet resin composition was dissipated and removed by holding for minutes.

The whole of the porous substrates 30 and 40 in the above state was pressed by a well-known roller at a pressure of 400 kgf / cm ² . The porous substrates 30, 4 pressed in this way
0 was carried into a heating furnace and baked at a temperature of 370 ° C. for 10 minutes. In this way, as shown in FIG. 6, a multilayer sliding member 50 (Example) in which the porous base material 30 was filled with the synthetic resin layer 52 was produced. Further, as shown in FIG. 7, a multilayer sliding member 60 (Comparative Example) in which the porous base material 40 was filled with the synthetic resin layer 62 was manufactured. When the entire porous substrate 30 in which the porous sintered layer 28 was filled with the resin composition was pressed with a roller, the porous sintered layer 28 was plastically deformed.

The peel strength of the synthetic resin layers 52 and 62 filled and coated on the porous sintered layers 28 and 42 of the two types of multilayer sliding members 50 and 60 manufactured as described above was measured.

<Method of Measuring Peel Strength> A method of measuring the peel strength will be described with reference to FIG.

FIG. 8 is a schematic view showing a method for measuring the peel strength.

The method for measuring the peel strength of the synthetic resin layers 52, 62 of the two types of multilayer sliding members 50, 60 is exactly the same. Here, the multi-layer sliding member 50 will be described as an example.

In measuring the peel strength of the synthetic resin layer 52, first, the synthetic resin layer 52 is
(See FIG. 4). The multi-layer sliding member 50 from which the synthetic resin layer 52 had been peeled was chucked in a vise 70, and the peeled synthetic resin layer 52 was sandwiched and fixed to a distal end portion 72a of a fixing jig 72. Fixing jig 7
2, a push-pull gauge 74 was attached, the synthetic resin layer 52 was pulled in a 180 ° direction (a direction parallel to the steel plate), and the strength at that time was measured by the push-pull gauge 74.

As a result of the measurement as described above, the peel strength of the synthetic resin layer 52 of the multilayer sliding member 50 using the porous substrate 30 of Examples 1 and 2 (see FIG. 4) was 2.74 kg.
f / cm. On the other hand, the peel strength of the synthetic resin layer 62 of the multilayer sliding member 60 using the porous substrate 40 of the comparative example was 1.84 kgf / cm.

From the measurement results, it is found that the peel strength of the synthetic resin layer 52 of the multilayer sliding member 50 is about 50% higher than the peel strength of the synthetic resin layer 62 of the multilayer sliding member 60. Was. The reason is presumed to be as follows.

As can be seen from the porous substrate 30 schematically shown in FIG. 4 and the multilayer sliding member 50 schematically shown in FIG. 6, the porous sintered layer 28 of the porous substrate 30 Plastic deformation occurs due to the pressing force of the roller when the porous sintered layer 28 is filled with the synthetic resin. As a result of this plastic deformation,
It is presumed that the bonding force between the synthetic resin layer 52 and the porous sintered layer 28 was increased, and this bonding force was added to the anchoring effect of the porous sintered layer 28.

When the peel strength of the synthetic resin layer 52 is high, the plate-shaped multilayer sliding member 50 may be bent into a cylindrical shape, or a flange may be attached to the end of the cylindrical sliding member 50 bent. When performing processing, the synthetic resin layer 52 does not peel off. Therefore, the peel strength of the synthetic resin layer 52 is an extremely important factor when processing the plate-shaped multilayer sliding member 50.

[0061]

As described above, according to the porous substrate of the present invention, the first sintered layer uniformly covers the surface of the substrate. Therefore, since the surface of the substrate and the first sintered layer are in sufficient contact, the bonding strength between the substrate and the first sintered layer is high (strong). In the second sintered layer, a large number of irregularly shaped particles are combined with each other to form a large number of voids therein, so that a large number of irregularities are formed inside the second sintered layer. It will be. For this reason, when the second sintered layer is filled and impregnated with, for example, a resin, the resin is caught on the irregularities of the second sintered layer. As a result, the so-called anchor effect (anchor effect) is enhanced, so that the resin
From the sintered layer, and the peel strength increases.

Here, when the substrate is made of steel, the strength of the substrate is high, so that a porous substrate having high strength can be obtained.

When the first and second sintered layers are made of bronze, a sintered layer having excellent corrosion resistance can be obtained.

Further, when the bronze has a composition comprising 9 wt% to 12 wt% of tin, 0.01 wt% to 0.50 wt% of phosphorus, and the balance copper,
Since it contains 9% by weight or more and 12% by weight or less of tin,
The bonding strength between the first sintered layer and the steel sheet is increased. Also,
Since it contains 0.01% by weight or more and 0.50% by weight or less of phosphorus, when a large number of irregularly shaped particles are sintered to form the second sintered layer, each particle is deformed. It is difficult to maintain the irregular shape. As a result, the so-called anchor effect is further enhanced, so that the resin filled and coated in the second sintered layer is less likely to be peeled off from the second sintered layer, and the peel strength is further increased.

Further, according to the method for producing a porous substrate of the present invention, in the vibration step, a large number of spherical particles pass between a large number of irregularly shaped particles and collect on the surface of the substrate. For this reason, many irregularly shaped particles gather on and cover many spherical particles. In this state, the powder layer is sintered in the sintering step. In this case, many spherical particles are in a liquid phase and cover the surface of the substrate uniformly. Therefore, a layer (first sintered layer) formed by sintering a large number of spherical particles and the surface of the substrate are sufficiently in contact with each other, so that the bonding strength between the substrate and the first sintered layer is high ( strong). On the other hand, a large number of irregularly shaped particles partially become a liquid phase, but are sintered while maintaining a substantially irregular shape. Therefore, in a layer formed by sintering a large number of irregularly shaped particles (second sintered layer), a large number of irregularly shaped particles are bonded to each other to form a large number of voids therein. A large number of irregularities are formed inside the second sintered layer. For this reason, when the second sintered layer is filled and impregnated with, for example, a resin, the resin is caught on the irregularities of the second sintered layer. As a result, the so-called anchor effect (anchor effect) is enhanced, so that the resin is less likely to be separated from the second sintered layer, and the peel strength is increased.

Here, when the powder layer forming step is a step of forming the powder layer on the surface of a steel substrate, the strength of the substrate is high, so that a porous substrate having high strength can be obtained.

Further, in the case where the powder layer forming step is a step of forming a powder layer in which the spherical particles made of bronze and the irregular particles are mixed on the surface of the substrate,
Since the sintered layer is made of bronze, a sintered layer having excellent corrosion resistance can be obtained.

Furthermore, in the powder layer forming step, tin of 9 to 12% by weight, tin of 0.01 to 0.
In the case where the step of forming a powder layer in which the spherical particles and the irregularly shaped particles made of bronze having a composition of 50% by weight or less of phosphorus and copper as the balance is copper is formed on the surface of the substrate, 9 Since tin is contained in an amount of not less than 12 wt% and not more than 12 wt%, the bonding strength between the first sintered layer formed by sintering a large number of spherical particles and the steel sheet is enhanced. Also, 0.0
Since it contains 1% by weight or more and 0.50% by weight or less of phosphorus, when a large number of irregularly shaped particles are sintered to form a second sintered layer, each of the particles is hardly deformed. The irregular shape is maintained. As a result, the so-called anchor effect is further enhanced, so that the resin filled and coated in the second sintered layer becomes the second sintered layer.
From the sintered layer, and the peel strength is further increased.

Further, the powder layer forming step is a step of forming, on the surface of the substrate, a powder layer in which the large number of spherical particles having an average particle size smaller than the average particle size of the large number of irregularly shaped particles are mixed. In the case where the average particle size of many spherical particles is smaller than the average particle size of many irregularly shaped particles, the spherical particles easily pass between the irregularly shaped particles in the vibration step. Therefore, many spherical particles tend to collect on the surface of the substrate. As a result, the substrate and the first sintered layer are more strongly joined. In addition, since the irregularly shaped particles tend to collect on the spherical particles, the second sintered layer has a higher anchoring effect.

Further, in the powder layer forming step, all the particles consisting of the large number of spherical particles and the large number of irregularly shaped particles are particles passing through 60 mesh, and passing through 250 mesh, And spherical particles having an apparent density of 3.6 g / cm ³ or more and 4.2 g / cm ³ or less and an amount of 30% by weight or more and 50% by weight or less of all the particles; Passing through a mesh but not passing through 200 mesh, and having an apparent density of 3.1 g / cm ³ or more and 3.5 g / cm ³ or less;
Further, in a case where the step of forming a powder layer in which irregular particles present in an amount within a range of 35% by weight or more and 50% by weight or less of all the particles are mixed is formed on the surface of the substrate, In addition, spherical particles are more likely to pass between irregularly shaped particles. Therefore, many spherical particles are more likely to collect on the surface of the substrate. As a result, the substrate and the first sintered layer are joined even more strongly. In addition, since the irregularly shaped particles are more likely to collect on the spherical particles, the second sintered layer has an even higher anchoring effect.

Further, the sintering step is performed in a heating furnace adjusted to a neutral atmosphere or a reducing atmosphere.
30 minutes or more at a temperature within the range of 0 ° C or more and 950 ° C or less
In the case where the sintering is performed for a time within the range of 0 minute or less, the spherical particles surely become a liquid phase and uniformly cover the surface of the substrate. Therefore, the substrate and the first sintered layer are more securely joined. Further, since a large number of irregularly shaped particles can more reliably maintain an irregular shape, a so-called anchor effect can be more reliably exerted.

Further, according to the multilayer sliding member of the present invention, since a large number of irregularities are formed inside the second sintered layer, the resin layer is caught by these irregularities. For this reason, the so-called anchor effect is enhanced, so that the resin layer is less likely to be separated from the second sintered layer.

Here, when the resin layer is made of a fluororesin, a multilayer sliding member having more excellent sliding properties can be obtained.

According to the method for manufacturing a multilayer sliding member of the present invention, the second sintered layer is formed by sintering a large number of irregularly shaped particles. Many irregularities are formed inside. The resin layer is caught on these irregularities. Furthermore, since the second sintered layer is plastically deformed, the second sintered layer cuts into the resin layer. For this reason, the so-called anchor effect is greatly enhanced, and the resin layer is very unlikely to be separated from the second sintered layer. Therefore, a long-life multilayer sliding member can be obtained.

[Brief description of the drawings]

FIG. 1 is a schematic diagram showing a schematic configuration of a manufacturing apparatus for manufacturing a porous substrate.

FIG. 2 is a cross-sectional view schematically showing the powder immediately after being sprayed on a steel plate.

FIG. 3 is a cross-sectional view schematically showing a state after vibrating the steel plate and the powder of FIG. 2;

4 is a cross-sectional view schematically showing a porous substrate obtained by sintering the powder shown in FIG.

FIG. 5 is a cross-sectional view schematically showing a porous substrate of a comparative example.

FIG. 6 is a cross-sectional view schematically showing a multilayer sliding member of an example.

FIG. 7 is a cross-sectional view schematically illustrating a multilayer sliding member of a comparative example.

FIG. 8 is a schematic view showing a method for measuring peel strength.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 20 Steel plate 22 Bronze powder 24 Bronze powder layer 26 Joining layer 28 Porous layer 28a Void 30 Porous base material 50 Multi-layer sliding member 52 Synthetic resin layer B Spherical particle I Irregular shaped particle

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI theme coat ゛ (Reference) F16C 33/12 F16C 33/12 B 33/14 33/14 A 33/20 33/20 Z (72) Invention Person Yoshinori Mizuno 8 Kirihara-cho, Fujisawa-shi, Kanagawa Prefecture F-term in Oiles Corporation Fujisawa Plant (reference) 3J011 LA01 QA05 SB02 SB03 SB05 SB19 SC04 4K018 AA05 AA24 BB01 BB03 BB04 CA05 CA45 DA11 FA47 JA25 JA32 JA38 KA03 KA22

Claims (14)

[Claims] 1. A substrate having a predetermined thickness, a first sintered layer uniformly covering the surface of the substrate, and a number of irregularly shaped particles bonded to each other to form a number of voids therein. And a second sintered layer that covers the first sintered layer continuously from the first sintered layer. 2. The porous substrate according to claim 1, wherein the substrate is made of steel. 3. The porous substrate according to claim 1, wherein the first and second sintered layers are made of bronze. 4. The bronze has a composition comprising 9 wt% to 12 wt% of tin, 0.01 wt% to 0.50 wt% of phosphorus, and the balance copper. The porous substrate according to claim 3, wherein 5. A method for producing a porous substrate in which a porous sintered layer is formed on a surface of a substrate having a predetermined thickness, the method comprising the steps of: A powder layer forming step of forming a mixed powder layer on the surface of the substrate, a vibration step of vibrating the powder layer formed on the surface of the substrate, and after or after the vibration step, A sintering step of sintering the powder layer formed on the surface of the substrate. 6. The method according to claim 5, wherein the powder layer forming step is a step of forming the powder layer on a surface of a steel substrate. 7. The method according to claim 5, wherein the powder layer forming step is a step of forming a powder layer in which the spherical particles and the irregular particles made of bronze are mixed on the surface of the substrate. 7. The method for producing a porous substrate according to 6. 8. The powder layer forming step is made of bronze having a composition of 9 wt% to 12 wt% of tin, 0.01 wt% to 0.50 wt% of phosphorus, and the balance being copper. 8. The method for producing a porous substrate according to claim 5, wherein the step of forming a powder layer in which the spherical particles and the irregular particles are mixed is formed on the surface of the substrate. . 9. The powder layer forming step is a step of forming, on the surface of the substrate, a powder layer in which the plurality of spherical particles having an average particle size smaller than the average particle size of the plurality of irregularly shaped particles are mixed. The method for producing a porous substrate according to any one of claims 5 to 8, wherein: 10. The powder layer forming step, wherein all of the large number of spherical particles and the large number of irregularly shaped particles are particles passing through 60 mesh, and passing through 250 mesh, and The apparent density is 3.6 g / cm ³ or more and 4.2 g / cm ³ or less, and 30% by weight or more and 50% by weight of all the particles.
Spherical particles present in an amount within the following range, passing through 100 mesh but not passing through 200 mesh, and having an apparent density of 3.1 g / cm ³ or more and 3.5 g /
cm ³ or less, and 35% by weight of all the particles.
10. The method according to claim 5, wherein a step of forming a powder layer on the surface of the substrate, the powder layer being mixed with irregularly shaped particles present in an amount in the range of not less than 50% by weight. The method for producing a porous substrate according to claim 1. 11. The sintering step is performed in a heating furnace adjusted to a neutral atmosphere or a reducing atmosphere at a temperature within the range of 850 ° C. or more and 950 ° C. or less.
The method for producing a porous substrate according to claim 10, wherein the sintering is performed for a time within a range of not less than 60 minutes and not more than 60 minutes. 12. The porous substrate according to claim 1, wherein the porous substrate has a second shape.
And a resin layer that is filled and coated on the sintered layer. 13. The sliding member according to claim 12, wherein the resin layer is made of a fluororesin. 14. A multilayer sliding member having a porous substrate having a porous sintered layer formed on a surface of a substrate having a predetermined thickness, and a resin layer filled and coated on the porous sintered layer. A method for manufacturing a multilayer sliding member to be manufactured, wherein each step of the method for manufacturing a porous substrate according to any one of claims 5 to 11, and a plurality of irregularly shaped particles are sintered. Forming a resin layer by filling and coating the second sintered layer with a resin while plastically deforming the formed second sintered layer. A method for manufacturing a moving member.