JP3108363B2 - Copper-lead alloy bearing containing indium and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copper-lead alloy bearing containing indium and a method of manufacturing the same, and more particularly, to a copper-lead alloy alloy bearing layer applied to a steel plate backing.
A copper-lead system which is formed by sandwiching a lead-tin overlay layer containing lead and tin between upper and lower overlay layers consisting essentially of indium, and which has excellent load-bearing capacity and withstands long-term use. The present invention relates to an alloy bearing and a manufacturing method thereof.

[0002]

2. Description of the Related Art Conventionally, the driving of automobiles, vehicles and other
Bearings such as flat bearings have been developed and used for running internal combustion engines for heavy loads. This bearing is constituted by, for example, using a steel plate formed in a half-split or cylindrical shape as a backing metal, and applying an alloy bearing layer made of a copper-based alloy or the like on the steel plate backing metal to form a multilayer structure.

[0003] These high-load bearings are excellent in load-bearing capacity, because the alloy bearing layer is made of a copper-based alloy. However, in recent years, the conditions required for driving and driving automobiles and vehicles have become extremely severe, and in order to meet the conditions, in addition to load resistance, various characteristics required as a bearing, that is, , Seizure resistance, foreign matter burying property, conformability, etc. are required.

In order to meet these demands and to solve the problems arising from these demands, in addition to strengthening the alloy bearing layer on the steel backing, a metal or alloy having conformability and embeddability is alloyed. An overlay layer is formed on a bearing layer by plating or the like.

FIG. 4 is a sectional view showing a part of a bearing developed for high load. As shown in FIG. 4, the bearing 20 has an alloy bearing layer 2 mainly made of copper containing lead or tin as required, which is formed on a steel backing metal 1 by sintering or casting. Have been.

On the alloy bearing layer 2, an overlay layer 4 is formed by plating.

Normally, the overlay layer 4 is formed as a plating layer of a lead-tin alloy containing lead and tin which provides excellent bearing characteristics, and between the overlay layer 4 and the alloy bearing layer 2 having this composition. Is provided with a nickel plating layer 7 having a thickness of about 1 to 2 μm, and the nickel plating layer 7 enhances the adhesion between the alloy bearing layer 2 and the overlay layer 4.

[0008] By the way, recent high load internal combustion engines and engines are required to be used for a long period of time even after the surface overlay layer 4 has been worn away for a considerable period of time and thereafter worn out. . In other words, it is required to be used even when the overlay layer on the surface is lost.

However, in the conventional bearing shown in FIG. 4, a hard nickel plating layer 7 is interposed between the alloy bearing layer 2 and the overlay layer 4, so that the overlay layer 4 may be used for a considerable period of time. When the wear disappears, the interposed hard nickel plating layer is exposed on the surface, causing seizure. In short, in the conventional alloy bearing, while there is an overlay layer on the surface, it meets the demand for a high load.
After the disappearance of the valley layer, it cannot withstand use for high loads.

Further, depending on use conditions, the intervening nickel plating layer 7 disappears, and the underlying alloy bearing layer 2 is exposed on the surface. At this time, bearing components such as lead are melted out of the alloy bearing layer 2, and the corrosion resistance and the seizure resistance are greatly reduced.

If the nickel plating layer 7 is not interposed, the adhesion of the overlay layer 4 to the alloy bearing layer 2 cannot be enhanced, and the heat treatment process during the production of the bearing, the operation of the internal combustion engine, etc. In addition, components such as tin contained in the overlay layer 4 diffuse into the alloy bearing layer 2. For this reason, even if the overlay layer 4 is formed on the alloy bearing layer 2,
Components such as tin in the overlay layer 4 are reduced, and the corrosion resistance, fatigue resistance, and the like are not so improved.

In short, in the conventional alloy bearing, even when the overlay layer is formed, the life of the overlay layer itself is short, the overlay layer wears out, and the alloy bearing layer is exposed. Further, in the alloy bearing layer exposed on the surface, tin and the like do not sufficiently dissolve into the lead phase in the alloy bearing layer, so that the alloy bearing layer is rapidly corroded and seizure occurs, which is a serious problem.

[0013]

SUMMARY OF THE INVENTION An object of the present invention is to solve or improve the above-mentioned problems and problems. Specifically, the present invention relates to a method in which a copper-lead-based alloy bearing layer formed on a steel sheet back metal is provided. Forming a lead-tin overlay layer containing lead and tin without interposing a nickel plating layer or the like, and forming upper and lower portions substantially made of indium on the upper and lower portions of the lead-tin overlay layer. Overlay layer and lead
The tin overlay layer forms the overlay layer of the copper-lead alloy bearing.

Therefore, since the hard nickel plating layer does not intervene on the surface of the copper-lead alloy bearing layer, during heat treatment or operation, indium in the lower overlay layer is well contained in the lead phase of the bearing alloy layer. Even during heat treatment during manufacturing or during operation, indium in the lower overlay layer diffuses into the alloy bearing layer and penetrates deeply, and the alloy bearing layer itself has a load resistance, Sufficient seizure resistance, fillability, and conformability can be maintained.

[0015]

That is, the alloy bearing according to the present invention is a copper bearing having a lead phase dispersed in a matrix.
A lower overlay layer substantially composed of indium is formed on the lead alloy bearing layer, and a lead-tin overlay layer containing lead and tin is formed on the lower overlay layer. An upper overlay layer substantially made of indium is formed on the lead-tin overlay layer.

In order to produce such an alloy bearing, a lower overlay layer substantially made of indium is plated on a copper-lead alloy bearing layer in which a lead phase is dispersed in a matrix. After being formed as a layer, a lead-tin overlay layer containing lead and tin is formed as a plating layer on the lower overlay layer continuously, and thereafter, the lead-tin overlay layer is formed. On top, after forming an upper overlay layer substantially composed of indium as a plating layer,
The heat treatment is performed at a temperature of 150 ° C. ± 5 ° C.

Therefore, these means and their actions will be described in detail as follows.

First, an alloy bearing 10 according to the present invention is configured as shown in FIG. 1 as will be described in detail later. A copper-lead alloy bearing layer 2 is provided on a steel plate backing 1 and an upper overlay is provided. A layer 5, a lower overlay layer 3 and a lead-tin overlay layer 4 are laminated.

When each of these overlay layers is used for a long period of time, a part or all of each overlay layer is worn away and used.

Then, the state where each overlay layer is present and the state where it has been worn away by use is examined from the viewpoint of seizure resistance. The results are as follows. The life of the overlay layer can be extended,
Even if each overlay layer is worn away and the alloy bearing layer 2 is exposed on the surface, more excellent seizure characteristics are provided.

FIG. 1 is an explanatory view showing a part of an alloy bearing according to one embodiment of the present invention in cross section. In the bearing 10 represented by the reference numeral 10 in FIG. 1, the alloy bearing layer 2 is formed on the surface of the steel plate backing 1 similarly to the alloy bearing 20 according to the conventional example shown in FIG.

The alloy bearing layer 2 is made of a copper-lead alloy,
In the matrix, the lead particle phase is dispersed separately from the main component copper. In addition, components such as tin can be included, but when tin is mixed, the matrix is strengthened by alloying with copper.

The alloy bearing layer 2 can be formed as a cast alloy or a sintered alloy.

When the alloy bearing layer 2 is formed as a cast alloy, the load resistance and the like are improved as compared with the case where the alloy bearing layer 2 is formed as a sintered alloy.

However, when the structure shown in FIG. 1 is used, as shown in the examples described later, even if the alloy bearing layer 2 is made of a sintered alloy or a cast alloy, it shows almost the same load resistance. The reason is that the lead-tin overlay layer 4 exists on the surface of the alloy bearing layer 2 without the interposition of the nickel plating layer, and the lower tin-overlay layer 4 is provided between the lead-tin overlay layer 4 and the alloy bearing layer 2. It is considered that because the valley layer 3 is interposed, indium in the lower overlay layer and tin in the lead-tin overlay layer penetrate deeply into the alloy bearing layer made of a sintered alloy.

More specifically, a lead-tin based overlay layer 4 containing lead and tin is formed on the alloy bearing layer 2, and the lead-tin based overlay layer 4 and the alloy bearing layer 2 are formed. And the lower overlay layer 3 is interposed therebetween.

Further, an upper overlay layer 5 is formed on the lead-tin based overlay layer 4, and on the alloy bearing layer 2,
The lead-tin-based overlay layer 4 is sandwiched between the upper overlay layer 5 and the lower overlay layer 3 to form an overlay layer integrally with the upper overlay layer 3, whereby load resistance and adaptability are achieved. Properties required for high load resistance, such as resistance, burial, and corrosion resistance, are provided.

Each of the overlay layers 3, 4 and 5 is formed by plating, in which the lead-tin based overlay layer 4 is formed.
Is formed as a lead plating layer, and the bearing performance is improved by these bearing components.

The upper and lower overlay layers 5, 3 are:
Each of them has the same composition, is substantially made of indium, and contains only inevitable impurities as other components.

As described above, when the lead-tin-based overlay layer 4 is provided on the upper and lower sides with the upper and lower overlay layers 5 and 3 substantially made of indium interposed therebetween, the heat treatment during manufacture and the use during use can be improved. In addition, components such as indium and tin can diffuse and move toward the alloy bearing layer 2 from the lower overlay, the lead-tin overlay layer, and the like, greatly improving the corrosion resistance and the like of the alloy bearing layer 2.

Since the upper overlay layer 5 is also substantially made of indium, the indium and tin deficient in the alloy bearing layer 2 are removed by the migration of indium and the like from the upper overlay layer 5. Be supplemented. For this reason, each of these overlay layers imparts conformability and burying properties as a bearing, and even when these overlay layers are worn out, components such as indium and tin are sufficient in the alloy bearing layer 2. Since the amount is maintained, it can be used as it is for high loads.

As described above, in the present invention, an overlay layer having a laminated structure is provided on the alloy bearing layer 2, and this bearing can be manufactured as follows.

Referring to FIG. 1, an alloy bearing layer 2 made of a copper-lead alloy as a cast alloy or a sintered alloy is formed on a back metal 1 such as a steel plate.

Next, a lower overlay layer 3 is formed on the alloy bearing layer 2 as a plating layer using a plating bath substantially made of indium.

Next, a lead-tin based overlay layer 4 is formed continuously using a lead-tin based plating bath.

Further, an upper overlay layer 5 is formed thereon as a plating layer again by using a plating bath made of indium.

Thus, the three overlay layers 3, 4, 5
Are sequentially laminated, and then heat-treated at, for example, 130 to 160 ° C., preferably 150 ° C. ± 5 ° C. When the heat treatment is performed in this manner, tin, indium, and the like in each of the overlay layers 3, 4, and 5 are diffused and dissolved in the lead phase in the alloy bearing layer 2, and properties such as corrosion resistance are greatly enhanced.

That is, when the respective overlay layers are sequentially laminated, they are then diffused into the lead phase in the alloy bearing layer 2 such as indium and tin in each overlay layer by heat treatment. This diffusion is carried out mainly by indium and the like in the lower overlay layer immediately above the alloy bearing layer, but this diffusion causes a shortage of indium and the like in the overlay layer. However, this shortage is sufficiently compensated for by indium and the like in the upper overlay layer.
In view of the entire valley layer, the residual ratio of tin, indium, and the like becomes higher, and indium diffuses and penetrates deeper into lead particles in the copper-lead alloy bearing layer than conventional ones.

Therefore, the life of the overlay layer is improved,
The overlay layer is worn away and the alloy bearing layer is exposed, and tin and indium have already been dissolved in the lead particles therein. For this reason, seizure resistance is improved by only the alloy bearing layer, and a copper-lead alloy bearing having excellent durability that can be used for a long time can be obtained.

[0040]

Next, an embodiment will be described.

Embodiment 1 First, the alloy bearings according to the respective examples were configured as shown in FIG. 1, and an alloy bearing layer 2 having the composition shown in Table 1 was formed on the back metal 1 of these alloy bearings.

As shown in Table 1, this alloy bearing layer 2
A cast alloy obtained by a casting method comprising 24% Pb, 2% Sn, balance copper and unavoidable impurities (indicated as A in the alloy type in FIGS. 1 and 2), 17% Pb, 5% Sn, balance copper and A sintered alloy obtained by a sintering method comprising unavoidable impurities (shown as B in the alloy type in FIGS. 1 and 2).
And consists of

A lower overlay layer 3 made of an indium plating layer is directly formed on the surface of the alloy bearing layer 2 by electroplating, and a Pb-Sn plating layer is continuously formed on the surface of the lower overlay layer 3. Is formed on the surface of the lead-tin overlay layer 4, and an upper overlay layer 5 made of an indium plating layer is formed on the surface of the lead-tin overlay layer 4 by electroplating.

The thickness of these three overlay layers 3, 4, 5 is 20 microns. Lower overlay layer 3
Although the upper overlay layer 5 and the upper overlay layer 5 are plated with the same amount of integrated current, they need not always be the same.

After each overlay layer was formed by the above plating process, a heat treatment was performed at a temperature of 150 ° C.

In each of Example Nos. 1
Nos. 5 to 5 consist of three overlay layers after the heat treatment step.
The components of the valley layer were as shown in Table 2.

In these embodiment Nos. 1 to 5 were used as test pieces with an overlay layer in later tests.

After the heat treatment step, the depth of penetration of indium into the lead phase in the alloy bearing was 6 μm.

The penetration depth in this case is the depth from the original position to the point where the indium diffuses and exists in the Pb particles in the alloy bearing by the heat treatment.

As a comparative example, a bearing having the structure shown in FIG. 2 was constructed. Also in this bearing, two kinds of alloy bearing layers 2 are used, and a lead-tin overlay layer 4 as a Pb-Sn plating layer is directly formed on the surface of the alloy bearing layer 2, and the lead-tin overlay layer 4 is formed. On the surface of the valley layer 4, an upper overlay layer 5 made of an indium plating layer is formed by electroplating. The thickness of the two overlay layers is 20 microns.
It is Torr.

This comparative example was also heat-treated at a temperature of 150 ° C. 6 to 9. The components of the overlay layer after the heat treatment step are as shown in Table 2. In the comparative example, the depth of penetration of indium into the alloy bearing after the heat treatment step is as shallow as 0 to 1 micrometer.

Embodiment 2 FIG. Next, assuming a state of actual use, the embodiment No. 1 is used. Nos. 1 to 5 and Comparative Example Nos. 6-9
The test piece with a valley was subjected to a diffusion treatment at a temperature of 170 ° C. for 1000 hours. The overlay components after 100 hours of the diffusion treatment are shown in Table 2, and the penetration depth of indium into the lead phase in the alloy bearing is shown in FIG.

After 100 hours of the diffusion treatment, the penetration depth of indium in the example was 55 μm, which is about twice as large as that in the comparative example.

Next, in order to evaluate the disappearance of the overlay layer wear, the overlay layer was removed from each of the test pieces of the embodiment and the comparative example subjected to the diffusion treatment. 1 '
~ 5 ', Comparative Example No. 6 ′ to 9 ′, and after these were subjected to a diffusion treatment, each was used as an overlay layer removal test piece.

Each of the test pieces prepared as described above was subjected to a baking test using a Suzuki type friction and wear tester.

The test conditions are as follows. Service tester: Suzuki friction and wear tester Initial load: 20 kgf Cumulative load: 10 kgf Speed: 1 m / sec Time: 10 min / 1 step Lubrication: Coating SAE 7.5W-30 Partner shaft: S45C HRc {50 Ra} 0.2 Seizure judgment criteria: BBT 200 ° C or higher or frictional force 25.2
kgf or more Specimen shape: 35 mm square flat plate with 4 mm center hole

The baking test was conducted in Example No. Nos. 1 to 5 and Comparative Example Nos. Test pieces with overlay of Nos. 6 to 9 and Examples 1 'to
5 ', and the overlaid elimination test pieces after diffusion treatment of Comparative Examples 6' to 9 '.

For comparison, two kinds of base materials (specimens of an alloy bearing layer without an overlay layer formed by plating) were also tested.

Table 3 shows the results of the baking test.

It can be seen that in the case of overlaying, the working example has a higher seizure limit load than the comparative example.

This has a sandwich structure in which the upper and lower overlay layers above and below the indium plating layer in the overlay layer are arranged vertically, so that the amount of reduction of tin and indium in the overlay layer is small. It is presumed that the life of the layer was extended. Also, as shown in Table 3, in the baking test of the overlay-removed test piece after the diffusion treatment as an evaluation after the overlay layer was worn away, as shown in Table 3, the example was compared with the comparative example and the base alloy bearing layer alone. Improved seizure resistance. As shown in FIG. 3, the penetration depth of indium into the lead phase in the alloy bearing layer is more deeply diffused and penetrated in the example than in the comparative example, which is presumed to be reflected in the results. .

The depth of diffusion of indium into the lead phase in the alloy bearing layer is preferably 5 μm or more after heat treatment and 40 μm or more after diffusion treatment at 170 ° C. for 100 hours. Is particularly effective.

[0063]

[Table 1]

[0064]

[Table 2]

[0065]

[Table 3]

[0066]

As described above in detail, according to the present invention, a lower overlay layer substantially composed of indium is formed on a copper-lead alloy bearing layer in which a lead phase is dispersed in a matrix. A lead-tin overlay layer containing lead and tin is formed on the lower overlay layer, and an upper overlay layer substantially made of indium is formed on the lead-tin overlay layer. Is formed.

For this reason, each overlay layer by thermal diffusion,
Above all, the amount of reduction of tin and indium in the lead-tin overlay layer is small, and the life of the overlay layer is extended, and even if the overlay layer wears out and the alloy bearing layer is exposed. However, since indium is deeply diffused in the lead phase in the alloy bearing layer, it has excellent seizure resistance. Therefore, a copper-lead-based alloy bearing more advantageous for long-term use can be obtained.

[Brief description of the drawings]

FIG. 1 is a sectional view of an alloy bearing according to one embodiment of the present invention.

FIG. 2 is a sectional view of an alloy bearing according to a comparative example.

FIG. 3 is a graph showing an indium penetration depth in relation to a diffusion time, comparing an example of the present invention with a comparative example.

FIG. 4 is a sectional view of a conventional alloy bearing.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 back metal 2 alloy bearing layer 3 lower overlay layer 4 lead-tin overlay layer 5 upper overlay layer 7 nickel plating layer

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) F16C 17/00-17/28 F16C 33/00-33/28 C22C 9/08 C25D 5/00-7 / 12

Claims (8)

(57) [Claims] 1. A lower overlay layer substantially made of indium is formed on a copper-lead alloy bearing layer in which a lead phase is dispersed in a matrix, and a lower overlay layer is formed on the lower overlay layer. Forming a lead-tin overlay layer containing lead and tin, and forming an upper overlay layer substantially made of indium on the lead-tin overlay layer. Copper-lead alloy bearing containing indium. 2. The copper-lead alloy bearing containing indium according to claim 1, wherein said copper-lead alloy bearing layer is a copper-lead alloy containing copper and lead as main components. . 3. The copper-lead-based alloy containing indium according to claim 1, wherein said copper-lead-based alloy bearing layer is a copper-lead-based sintered alloy containing copper and lead as main components. bearing. 4. The indium-containing copper-lead alloy according to claim 1, wherein at least a part of the indium diffuses into a lead phase in the copper-lead alloy bearing layer. Alloy bearing. 5. The copper-lead alloy bearing layer has a layer in which the indium has already diffused from the surface of the bearing alloy to a depth of about 5 μm or more after the heat treatment step in the lead phase in the copper-lead alloy bearing layer. The copper-lead alloy bearing containing indium according to claim 1, 2, 3, or 4. 6. A lower overlay layer substantially made of indium is formed as a plating layer on a copper-lead alloy bearing layer in which a lead phase is dispersed in a matrix. A lead-tin overlay layer containing lead and tin is formed as a plating layer on the lower overlay layer, and then the upper layer substantially made of indium is formed on the lead-tin overlay layer. A method for producing a copper-lead alloy bearing containing indium, comprising forming an overlay layer as a plating layer and then heat-treating it at 150 ° C. ± 5 ° C. 7. The indium-containing copper alloy according to claim 6, wherein said copper-lead alloy bearing layer is cast as a copper-lead alloy containing copper and lead as main components.
Manufacturing method of lead alloy bearings. 8. The copper containing indium according to claim 6, wherein said copper-lead alloy bearing layer is manufactured by sintering as a copper-lead based sintered alloy containing copper and lead as main components. -A method of manufacturing a lead alloy bearing.