JPH08261240A - Sliding bearing made of aluminium alloy - Google Patents

Abstract

PURPOSE: To provide an aluminium alloy sliding bearing which has the both of antinomic properties of high fatigue resistance and high surface performance. CONSTITUTION: This sliding bearing is composed of a laminated material of an alloy 1 and an alloy 2, where the composition of the alloy 1 is Sn: 0.1-12%, at least one of Pb or Sb: 0.1-3.0%, Si: 0.1-6.0%, at least one of Cu, Cr, Zn, Mn: 1.0-5.0%, the rest: substantially Al, and the composition of the alloy 2 is Pb: 4.0-12%, Sn 0.1-3.0%, Si: 3.1-5.0%, at least one of Cu or Cr: 0.1-3.0, the rest: substantially Al, by weight% respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bearing used as a structural part of various mechanical devices such as automobiles, machine tools, agricultural machines and the like, and an Al alloy slide bearing suitable as a material for sliding members.

[0002]

2. Description of the Related Art Recently, as a bearing alloy for an internal combustion engine, an Al-based bearing alloy has been attracting attention from the viewpoint of heat resistance, wear resistance, corrosion resistance, fatigue resistance, seizure resistance and the like. Among them, the Al-Sn-Pb type and the Al-Pb-Sn type are much superior to those of other materials in terms of the above performance, and thus the amount of use thereof has been rapidly increasing recently. ing.

[0003]

However, Al-based bearing alloys with Kelmet (mild steel base metal with a thickness of about 1 mm and high lead bronze (Pb 20-45 wt%).
In order to have the same level of fatigue resistance as the trade name of bearings backed by Cu alloys), including that of Kelmet, or Sn.
It is necessary to reduce the amount of soft components such as Pb and Pb, but in that case, since the seizure resistance is lowered, it was necessary to form a Pb-Sn-based overlay layer on the surface like Kermet.

However, in the high speed and high load range, Pb-S
It was confirmed by experiments that those having an n-based overlay layer on the surface exhibit a marked increase in friction than the surface layer of an Al-based bearing alloy having good thermal conductivity.

According to the conventional wisdom, in the high speed / high load range, when the temperature of the lubricating oil becomes high, the oil viscosity decreases, and the oil film becomes thin, and as a result, the friction as the shearing resistance of the oil decreases. At this time, the difference in bearing material has no effect.

As a result of some research conducted by the present inventors on the frictional behavior of the bearing when the temperature of the lubricating oil becomes high, the viscosity decreases as the temperature of the oil becomes high, and the oil film However, it was found that the oil film pressure was increased, and as a result, the oil viscosity under high pressure was significantly increased, which in turn increased the friction as the shear resistance of the oil. Further, under such a condition, the local high oil film pressure naturally impairs the fatigue resistance of the bearing.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of such conventional problems, and it is effective to lower the temperature of the oil film, which is the starting point of the mechanism, in order to reduce friction in a high speed / high load range. For that purpose, it is important to increase the thermal conductivity of the bearing alloy layer, which has the role of quickly removing the local heat generation of the intervening oil, with respect to the bearing material that was conventionally irrelevant. It is based on something.

By making the bearing alloy have high thermal conductivity, the friction loss in the lubricating oil in the high speed / high load range can be greatly reduced as compared with the conventional slide bearing.

Further, in addition to improving the strength of the bearing alloy, by reducing the intervening oil film pressure by using the bearing of the present invention having a high thermal conductivity, the fatigue resistance is improved and the surface performance is at a level not seen in the past. Can be achieved with.

Therefore, an object of the present invention is to provide a sliding bearing made of an Al alloy which can obtain both anti-fatigue properties and surface properties, which are trade-off characteristics, at a high level which has never been obtained.

[0011]

The Al alloy slide bearing according to the present invention has a weight percentage of Sn: 0.1 to 12%, of Pb and Sb, as set forth in claim 1. 1 type or 2 types: 0.1 to 3.0%, Si: 0.1 to 6.0
%, One or more selected from Cu, Cr, Zn and Mn: an alloy I containing 1.0 to 5.0% and the balance substantially Al, and Pb: 4.0-1
2%, Sn: 0.1 to 3.0%, Si: 3.1 to 5.0
%, Cu, one or two of Cr: 0.1 to 3.
It is characterized in that an alloy II containing 0% and the balance being substantially Al is laminated.

In an embodiment of the Al alloy slide bearing according to the present invention, as described in claim 2, between the alloy I and the alloy II, in weight%, Pb: 0.
1-6.0%, Sn: 0.1-3.0%, Si: 0.1
~ 5.0%, one or two of Cu and Cr: 0.
Alloy III containing 1 to 3.0%, the balance consisting essentially of Al and having a total amount of Pb and Sn less than Alloy II
Or an alloy layer substantially consisting of alloy A and alloy II is provided between the alloy I and the alloy II.
An intermediate layer consisting of only 1 is provided, or
Between alloy I and alloy II, P
An intermediate layer made of an Al alloy containing no b or Sn may be provided.

[0013]

The Al alloy slide bearing according to the present invention has the Sn:
0.1 to 12%, one or two of Pb and Sb:
0.1 to 3.0%, Si: 0.1 to 6.0%, Cu, C
One or more selected from r, Zn and Mn: Alloy I containing 1.0 to 5.0% and the balance substantially consisting of Al, and Pb: 4.0 in weight%. 12%, S
n: 0.1 to 3.0%, Si: 3.1 to 5.0%, C
One or two of u and Cr: 0.1 to 3.0% is included, and the balance is made of a structure in which an alloy II substantially consisting of Al is laminated. The reason for limiting the components and numerical values will be described together with the action of each element.

First, the reasons for limiting the components and numerical values of alloy I will be explained together with the action of each element.

(I-1) Sn: 0.1 to 12%, Pb,
One or two kinds of Sb: 0.1 to 3.0% Sn, Pb, and Sb are effective as a lubricating component and have excellent seizure resistance. Second
When the alloy II is laminated as a surface layer as the surface layer, the conformability and the foreign substance embedding property are not required, and Sn, Pb, and Sb are added to prevent seizure when the alloy II is worn. From the viewpoint of fatigue strength, it is better that these lubricating components are as small as possible. Further, in order to improve the thermal conductivity and suppress the increase of friction loss in high temperature lubricating oil, which is one of the features of the sliding bearing of the present invention, it is preferable that these lubricating components are as small as possible.

Therefore, Sn: 0.1 to 12%, P
One or two of b and Sb: 0.1 to 3.0%.

(I-2) Si: 0.1-6.0% Si strengthens the Al matrix, and Sn, P
Similar to b and Sb, it contributes to the prevention of seizure and wear when the alloy II is worn when the alloy II is laminated as a surface layer. However, if less than 0.1%, the effect is small,
If it exceeds 6.0%, mechanical properties, particularly elongation, are reduced and sliding performance or bearing performance is deteriorated.

(I-3) One or more selected from Cu, Cr, Zn and Mn: 1.0 to 5.0% Cu, Cr, Zn and Mn increase the strength of the Al matrix. It is effective for However, if it is less than 1.0%, its effect is small, and if it exceeds 5.0%, mechanical properties, particularly elongation, are reduced like Si, and sliding performance or bearing performance is deteriorated.

Next, the reasons for limiting the components and numerical values of Alloy II will be described together with the action of each element.

(II-1) Pb: 4.0-12% Pb is effective as a lubricating component and has excellent seizure resistance. Further, when the alloy II is used as the surface layer, the compatibility and the foreign matter embedding property are enhanced.

However, if it is less than 4.0%, its effect is small, and if it exceeds 12%, the thermal conductivity decreases, and friction loss in high temperature lubricating oil, which is one of the features of the sliding bearing of the present invention. The ability to control the increase in the

(II-2) Sn: 0.1 to 3.0% Similar to Pb, Sn has excellent seizure resistance and enhances the conformability and foreign matter embeddability when Alloy II is used as the surface layer. At the same time, it imparts corrosion resistance to Pb. However, if it is less than 0.1%, its effect is small, and if it exceeds 3.0%, the amount of Sn with respect to Pb is large, and the Pb-Sn eutectic component with a low melting point is large, so that a thin solder on the bearing surface during use. Since the coating film is formed and the thermal conductivity is lowered, the ability to suppress the increase of friction loss in high temperature lubricating oil, which is one of the features of the sliding bearing of the present invention, is impaired.

(II-3) Si: 3.1 to 5.0% Si contributes to the improvement of seizure resistance when alloy II is used as the surface layer, but if it is less than 3.1%, its effect is small. 5.
If it exceeds 0%, the conformability and workability such as rolling deteriorate.

(II-4) One or two kinds of Cu and Cr: 0.1 to 3.0% Cu and Cr are load-bearing when alloy II is used as a surface layer,
Although the heat resistance is improved, if it is less than 0.1%, its effect is small, and if it exceeds 3.0%, the conformability and workability such as rolling deteriorate.

Next, alloy II which can be used as the surface layer in the Al alloy sliding bearing according to the present invention
Regarding the manufacturing method of (1), usually, a method of rolling a plate material produced by powder rolling or sintering is used, but it is also possible to directly laminate it on the alloy I by thermal spraying.

Further, when the amounts of Pb and Sn in the alloy II are large, the adhesion with the alloy I may be deteriorated depending on the cladding conditions. In this case, as stated in claim 2, between alloy I and alloy II, in% by weight, Pb:
0.1-6.0%, Sn: 0.1-3.0%, Si:
0.1 to 5.0%, one or two of Cu and Cr
Species: an intermediate layer comprising 0.1 to 3.0%, the balance consisting essentially of Al, and the total amount of Pb and Sn consisting of alloy III being smaller than alloy II; As shown in FIG.
An intermediate layer made of only Al may be provided, or, as described in claim 4, an intermediate layer made of an Al alloy containing no Pb or Sn may be provided between the alloy I and the alloy II.

In this case, alloy III provided as the intermediate layer
Alloy with a Pb content of less than 0.1% as a surface layer
When I is worn out, the effect of preventing seizure and wear is lost,
If it exceeds 6.0%, the adhesion will deteriorate, so Pb is 0.1.
It is preferable to be up to 6.0%. When Sn is less than 0.1%, the effect of preventing seizure and wear when the alloy II, which is the surface layer, is worn is lost, and when it exceeds 3.0%, the adhesion is deteriorated. , Sn is preferably 0.1 to 3.0%. When Si is less than 0.1%, the effect of preventing seizure and wear when the alloy II as the surface layer is worn is lost, and when it exceeds 5.0%. Since the workability such as rolling decreases, Si is 0.1-5.0%.
If the total content of Cu and Cr is less than 0.1%, it will not contribute to the improvement of load resistance, and if it exceeds 3.0%, the workability such as rolling will be deteriorated. The total amount is preferably 0.1 to 3.0%, and further, in order to improve the adhesion between the alloy I and the alloy II, the total amount of Pb and Sn of the alloy III needs to be smaller than that of the alloy II. is there.

Similarly, between the alloy I and the steel plate serving as the back metal, an alloy layer III, a layer consisting essentially of Al, or an Al alloy layer containing no Pb or Sn is used to improve adhesion. You may intervene.

Regarding these intermediate layers, a method of making a laminated plate by powder rolling is usually used together with the alloy layer II.
There is no problem even if it is directly laminated on the side of the alloy I or alloy II which is in contact with the alloy I by clad, thermal spraying or the like.

In each of the alloy layers of the sliding bearing according to the present invention, Ti, B, Z, which are crystal grain refining elements of the Al alloy, are contained.
r, Ca, REM (one or more rare earth elements including Y and Sc), etc., and strengthening elements Mg, Ni, V, Fe, C
Of course, o and the like may be added if necessary.

[0031]

EXAMPLES Next, examples will be described together with comparative examples.

Examples 1 and 2 and Comparative Examples 1 and 2 First, an Al-Sn alloy having a composition shown in alloy I of Table 1 was cast by continuous casting as a plate-like material having a thickness of 20 mm, and each of the cast billets was cast. The lower surface was cut by 1 mm and then cold-rolled to a thickness of 8 mm. 200-in this state
Strain was removed by heat treatment at 300 ° C.

Subsequently, Al having the composition shown in alloy II of Table 1 was used.
-Pb-based alloy powder, 3.0% Pb, 0.3% by weight
% Sn, 0.9% Si, 0.5% Cu, balance substantially A
The alloy III powder consisting of 1 was made into a laminated plate having a thickness of 2 mm by powder rolling, sintered at 540 ° C., and then cold rolled to a thickness of 1 mm. 200 in this state
Strain was removed by performing a heat treatment at ˜300 ° C.

Edge cracks were removed from each of the two alloys by rolling, the contact surfaces were cleaned, clad so that alloy I and alloy III were in contact with each other, and then cold rolled to a thickness of 1 mm. .

After this laminated material was annealed, the alloy II was clad as a surface layer on a steel sheet and annealed. After that, the surface is further mechanically removed, and as a result, the thickness of the steel plate as the backing metal is about 1.2 mm, the thickness of the alloy layer I is about 0.25 mm, and the total thickness of the alloy layer II and the alloy layer III. A plain bearing having a thickness of about 0.05 mm and a total thickness of about 1.5 mm was obtained.

Examples 3 and 4 and Comparative Examples 3 and 4 First, an Al-Sn alloy having the composition shown in alloy I of Table 1 was cast by continuous casting into a plate-like material having a thickness of 20 mm, and each cast billet was cast. The lower surface was cut by 1 mm and then cold-rolled to a thickness of 8 mm. 200-in this state
Strain was removed by heat treatment at 300 ° C.

Subsequently, Al having the composition shown in Alloy II of Table 1 was used.
-Pb-based alloy powder and pure Al consisting essentially of Al
The powder and powder are rolled into a laminated plate having a thickness of 2 mm,
After sintering at 540 ° C., it was cold rolled to a thickness of 1 mm. In this state, heat treatment was performed at 200 to 300 ° C. to remove strain.

After the edge cracks caused by rolling were removed from these two alloys and the contact surfaces were cleaned, Alloy I and Pure A were used.
It was clad so as to be in contact with the 1-layer, and subsequently cold-rolled to a thickness of 1 mm.

After this laminated material was annealed, it was annealed by clad alloy II as a surface layer on a steel plate. After that, the surface is further mechanically removed, and as a result, the thickness of the steel plate as the back metal is about 1.2 mm, the thickness of the alloy layer I is about 0.25 mm, and the total thickness of the alloy layer II and the pure Al layer is A plain bearing having a thickness of about 0.05 mm and a total thickness of about 1.5 mm was obtained.

Examples 5, 6 and Comparative Example 5 First, an Al-Sn alloy having a composition shown in Table 1 as an alloy I was cast by continuous casting as a plate-like material having a thickness of 20 mm, and the upper and lower surfaces of each cast billet were The surface was cut by 1 mm and then cold-rolled to a thickness of 8 mm. 200-in this state
Strain was removed by heat treatment at 300 ° C.

Subsequently, Al having the composition shown in Alloy II of Table 1 was used.
-Pb alloy powder is powder-rolled into a plate having a thickness of 2 mm,
After sintering at 540 ° C., it was cold rolled to a thickness of 1 mm. In this state, heat treatment was performed at 200 to 300 ° C. to remove strain.

For these two alloys, the edge cracks caused by rolling were removed, the adhered surfaces were cleaned, and then clad,
Subsequently, it was cold rolled to a thickness of 1 mm.

Thereafter, this laminated material was annealed, and then the alloy II was clad on the steel sheet as a surface layer and annealed. Then, the surface is further mechanically removed. As a result, the thickness of the steel plate as the backing metal is about 1.2 mm, the thickness of the alloy layer I is about 0.25 mm, and the thickness of the alloy layer II is about 0.05 mm. Thus, a plain bearing having a total thickness of about 1.5 mm was obtained.

Comparative Example 6 The Al—Sn alloy of Comparative Example 6 (same as Example 1) shown in the column of Alloy I in Table 1 was cast by continuous casting as a plate-shaped material having a thickness of 20 mm, and was cast on a cast billet. The lower surface was cut by 1 mm and then cold-rolled to a thickness of 1 mm.
In this state, heat treatment was performed at 200 to 300 ° C. to remove strain.

After that, after clad on the steel plate, the surface is mechanically removed. As a result, the thickness of the steel plate as the backing metal is about 1.2 mm and the thickness of the alloy layer 1 is about 0.3 mm, which is a total. A plain bearing having a thickness of about 1.5 mm was obtained.

Comparative Example 7 Comparative Example 7 shown in the column of Alloy II in Table 1 (same as Example 1)
The Al-Pb based alloy powder of No. 3 was powder-rolled into a plate having a thickness of 4 mm, which was sintered at 540 ° C. and then cold-rolled to a thickness of 1 mm. In this state, heat treatment was performed at 200 to 300 ° C. to remove strain. Then, after clad on the steel plate and annealed, the surface is mechanically removed. As a result, the thickness of the steel plate as the backing metal is about 1.2 mm, and the alloy layer 1
A plain bearing having a thickness of I of about 0.3 mm and a total thickness of about 1.5 mm was obtained.

Comparative Example 8 The surface of the sliding bearing obtained in Comparative Example 6 was subjected to pretreatment such as degreasing, and then subjected to zinc substitution treatment, on which 10 wt% Sn,
20 μm Pb-Sn-Cu plating containing 2 wt% Cu
To obtain a plain bearing having a total thickness of about 1.5 mm.

Comparative Example 9 An alloy consisting of 25 wt% Pb, 3 wt% Sn and the balance substantially Cu (Kelmet compatible alloy) was melted and continuously poured onto a steel plate, and immediately after the pouring, the steel plate was poured. Cu-P with dendrite structure on the steel plate
The material which laminated the b-Sn alloy was produced. And after further dimensional adjustment, 10 wt% Sn, 2 wt% on it
Pb—Sn—Cu plating containing Cu was applied to a thickness of 20 μm to obtain a plain bearing having a total thickness of about 1.5 mm.

[0049]

[Table 1]

(Seizure resistance test) Examples 1 to 6 and Comparative Example 1
From each slide bearing obtained in ~ 9, width 35mm, length 35m
A test piece of m was cut out, and a seizure resistance test was performed using a Suzuki abrasion tester under the conditions shown in Table 2. Table 3 shows the results.

[0051]

[Table 2]

[0052]

[Table 3]

As is clear from Table 3, Example 1 of the present invention
It can be seen that the slide bearings of Nos. 6 to 6 have seizure resistance higher than that of the slide bearings of Comparative Examples 8 and 9, which have been considered to be more excellent in seizure resistance than before.

On the other hand, it is clear that the sliding bearings of Comparative Examples 2, 3 and 6 in which the component of the alloy II as the surface layer is out of the present invention are inferior in seizure resistance to the sliding bearings of the examples of the present invention. is there.

(High Temperature Friction) Examples 1 to 6, Comparative Example 8,
Each plain bearing obtained in No. 9 was processed into a half bearing shape, and a bearing unit testing machine developed by some of the present inventors (Japan Society of Mechanical Engineers)
Proceedings of the 71st National Convention vol. D, 1993, p. 332-334), the frictional force when the sliding surface became high temperature was measured under the conditions shown in Table 4. Sliding surface is 1
Table 5 shows the friction torque at 30 ° C.

[0056]

[Table 4]

[0057]

[Table 5]

As is clear from Table 5, Example 1 of the present invention
It can be seen that the slide bearings of Nos. 6 to 6 have better abrasion resistance than the slide bearings of Comparative Examples 8 and 9 having the Pb-Sn-Cu overlay layer on the surface.

(Fatigue Resistance Test) Examples 1 to 6 and Comparative Examples 1 to 1
Each slide bearing obtained in No. 8 was processed into a half bearing shape so as to be applied as an engine part, and an underwood test was conducted under the conditions shown in Table 6. The results are shown in Table 7.

[0060]

[Table 6]

[0061]

[Table 7]

As is clear from Table 7, Comparative Examples 1, 4, 5 in which the alloy component of the second layer (alloy I) is out of the present invention.
The slide bearing of No. 7 is inferior in fatigue resistance to the slide bearings of the examples.

Even if the alloy composition of the second layer (alloy I) satisfies the present invention, the alloy composition of the surface layer (alloy II) is from the present invention as in Comparative Examples 2, 3 and 6. The disengaged slide bearing is inferior in fatigue resistance to the slide bearings of the examples.

From these three types of test results, it is clear that the sliding bearing according to the present invention simultaneously achieves seizure resistance, fatigue resistance and reduction of friction loss in high temperature lubricating oil, and it is clear that various conventional sliding bearings are used. It was found that the bearing alloy had performances that were impossible.

[0065]

As described above, the Al alloy slide bearing according to the present invention has, as described in claim 1, Sn: 0.1 to 12% by weight, Pb and Sb. One or two of them: 0.1 to 3.0%, Si: 0.
1 to 6.0%, 1 or 2 or more selected from Cu, Cr, Zn and Mn: 1.0 to 5.0%, Alloy I containing the balance substantially Al, and weight %, Pb:
4.0-12%, Sn: 0.1-3.0%, Si: 3.
1 to 5.0%, one or two of Cu and Cr:
Since alloy II containing 0.1 to 3.0% and the balance substantially consisting of Al is laminated, both conventional anti-fatigue characteristics such as fatigue resistance and surface performance are conventional. In comparison with the conventional sliding member, it is realized at a high level that does not exist, especially in high temperature lubrication conditions, such as improved fluid lubrication performance to improve fatigue resistance and reduced friction heat generation to suppress temperature rise. The remarkable effect of being excellent is brought about.

In an embodiment of the Al alloy slide bearing according to the present invention, as described in claim 2, between the alloy I and the alloy II, in weight%, Pb: 0.
1-6.0%, Sn: 0.1-3.0%, Si: 0.1
~ 5.0%, one or two of Cu and Cr: 0.
Alloy III containing 1 to 3.0%, the balance consisting essentially of Al and having a total amount of Pb and Sn less than Alloy II
Or an intermediate layer consisting essentially of Al is provided between alloy I and alloy II as described in claim 3, or as described in claim 4. In addition, between alloy I and alloy II, A containing no Pb or Sn
The provision of the intermediate layer made of the 1-alloy has a remarkably excellent effect that the adhesion between the alloy I and the alloy II can be further improved.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shunichi Aoyama 2 Takaracho, Kanagawa-ku, Kanagawa Prefecture Nissan Motor Co., Ltd. (72) Inventor Ken Ushijima 2 Takara-cho, Kanagawa-ku, Yokohama Kanagawa Within the corporation

Claims (4)

[Claims] 1. Sn: 0.1-12% by weight, P
One or two of b and Sb: 0.1 to 3.0%,
Si: 0.1-6.0%, one or more selected from Cu, Cr, Zn, Mn: 1.0-5.0%
Alloy I with the balance substantially consisting of Al, and weight%
And Pb: 4.0-12%, Sn: 0.1-3.0%,
Si: 3.1 to 5.0%, one or two of Cu and Cr: 0.1 to 3.0%, with the balance substantially Al
Al, which is formed by stacking alloy II
Alloy plain bearings. 2. Between alloy I and alloy II, in% by weight, P
b: 0.1 to 6.0%, Sn: 0.1 to 3.0%, S
i: 0.1 to 5.0%, one or two of Cu and Cr: 0.1 to 3.0%, the balance substantially consisting of Al, and the total amount of Pb and Sn is The sliding bearing made of Al alloy according to claim 1, further comprising an intermediate layer composed of alloy III less than alloy II. 3. Between alloy I and alloy II, substantially Al
An intermediate layer consisting of only one is provided.
The sliding bearing made of Al alloy as described in 1. 4. The slide bearing made of an Al alloy according to claim 1, wherein an intermediate layer made of an Al alloy containing no Pb or Sn is provided between the alloy I and the alloy II.