JPH01212729A - Bearing material - Google Patents

Abstract

PURPOSE:To bring the capacity of a bearing material close to the level of Al or kelmt bimetal bearing alloy by dispersedly compounding specific inorganic fiber or whisker into a Pb-based alloy layer provided on the substrate of the bearing. CONSTITUTION:Fiber or whisker selected from Al2O3, Al2O3-SiO2, SiO2, SiC, BN, Si3N4, K2Ti6O13, etc., is dispersedly compounded into the Pb-based bearing alloy provided onto the substrate of the bearing material, by 5-50vol.%, for the total. Though the bearing material is slightly inferior to kelmet and Al bearing alloy in the aspect of fatigue resistance and load resistance, it is superior in the aspect of fitness, filling characteristics and seizure resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION C. OBJECTS OF THE INVENTION Industrial Application Field The present invention relates to a bearing material, and more specifically, to a bearing material containing a fiber-reinforced PB-based plain bearing alloy.

Conventional technology P known as Babbitt metal or white metal
b Base bearing alloy An alloy with hard metal 1f[I compound particles distributed in a soft base.It has a low melting point and excellent compatibility with the shaft, so it has high utility value and is used as the mainstream for bearing base metals. However, it has been found that there is a drawback in that fatigue strength significantly decreases as the bearing temperature increases due to high engine output and high oil temperature.

As a result, the main bearings and Hunrod bearings for passenger cars made in Japan after 1980 were almost entirely made of Kelmet and aluminum bearing alloys. Of course, efforts have been made to improve the performance of Bapit metal and the like, but as a result, no PB-based bearing alloy has emerged that outperforms Kelmet and aluminum bearing alloys.

Attempts have been made to improve the performance of conventional Babbitt metal alloys mainly through the addition of alloying elements, and although such attempts have achieved some degree of performance improvement, the performance achieved is insufficient for high engine output and high oil temperature. I couldn't adapt.

On the other hand, strong materials for FRM are generally made of Al.

0, SiC system, ALO, -8iO2 system, steel thread, glass fiber and A1□03. Inorganic fibers such as whiskers such as SiC, Si3N4, and graphite are used in combination with aluminum, copper, or iron matrices. Furthermore, it is widely known that such materials are useful for reducing the weight and increasing the strength of connecting rods for internal combustion engines.

Problems to be Solved by the Invention The addition of alloying elements to Babbitt metal, which has been attempted in the past, often leads to deterioration of various performances, and in particular, the fatigue resistance required for bearing materials for high-output internal combustion engines is extremely low. It becomes insufficient. As a countermeasure to this problem of insufficient fatigue resistance, progress has been made in the direction of making the lining thinner, so-called microbabbitt. However, this method is not perfect, and recently it has not been used as a high-speed, high-load bearing, but has only been used in cam bushes as a low- to medium-load bearing.

In addition to the above-mentioned fatigue resistance, Babbitt metals etc. have weaknesses such as low wear resistance and low corrosion resistance, and this is one of the reasons why Babbitt metals etc. have been replaced by other bearing base metals. .

The advantage of FRM as a bearing material is that its strength is improved by fiber reinforcement, and inorganic materials such as Al2O3 and SiC are
It has higher wear resistance than metal materials, especially lead alloys, which have one characteristic of being soft. It is clear that the excellent basic physical properties of FRM have an advantageous effect on improving bearing performance, but just because these properties are excellent does not mean that FRM can be used in bearings.

Inorganic materials such as Al2O, SiC do not have conformability and embeddability, so they do not have typical characteristics for use in bearings, and AI, O,...
Since SiC and the like cannot exhibit embeddability and conformability, the problem is how to achieve the embeddability and conformability of FRM.

By the way, individual properties such as the above-mentioned conformability can be tested in a laboratory. However, in the sliding bearings that are in practical use, these properties cannot be reproduced individually, and if any of the properties is insufficient, problems such as bearing seizure may occur.

Therefore, the present inventors conducted experiments and completed the present invention based on the idea that a practical bearing material could be provided by combining the compatibility and fiber reinforcement provided by inorganic fibers.

The object of the present invention is to bring the performance of a bearing material containing a PB-based plain bearing alloy as close as possible to the level of an Al-based or Kelmet-based bimetallic bearing alloy.

[Structure of the invention]

Means for Solving the Problems and Their Effects The present invention provides a bearing material in which a PBB bearing alloy layer is provided on a base material.
~50% by volume of A1201. A1□○, -8in2,5
in2. SiC, BN, Si3N, , K2Ti, 0
1. It is characterized by a dispersed composite of fibers or whiskers selected from the following.

Further, the base material is a backing steel plate, or the base material is a bimetallic material having an aluminum alloy or a copper alloy on a backing steel plate.

Furthermore, the present invention provides a bearing material in which a PBB bearing alloy layer is provided on an overlying base material.
．． It is characterized by containing 05 to 1% by weight of P.

That is, PB provided by electroplating or casting, etc.
5 to 50% by volume of A1□○1 in the base bearing alloy layer. A1□
O, -S i O2, S i O2, S i C, B
N.

S i, N1. K2T 1G01. By dispersing and compounding inorganic fibers or whiskers such as, and preferably by adding 0.05 to 1% by weight of P into the PB-based bearing base, the disadvantages of rapid deterioration of fatigue resistance and strength at high temperatures and It alleviates the disadvantages of low wear resistance and corrosion resistance, and maintains other bearing performances at or above the level of conventional PB bearing alloys.

The following p is one component of the bearing material according to the present invention.
The components of the bb bearing alloy layer will be explained.

A1□0, which is a component of the helical bearing material according to the present invention,
Al□0. -8 i 02. S i○zt S i
C,BN.

S LxN<r Inorganic fibers or whiskers such as K2TiGO□3 (hereinafter collectively referred to as "inorganic fibers, etc.")
) improves the strength, load resistance and fatigue resistance at high temperatures and wear resistance at room temperature of the lead-based alloy, which is another component, and also improves conformability by flattening the fine irregularities of the mating shaft. Departure jl! L is a component that improves the load resistance 41i by receiving the load from the mating shaft. The proportion of inorganic fiber used is generally 5-50%.
is good. Of this usage ratio, 20 to 50% has a large effect of improving high temperature strength, load resistance, and fatigue resistance. In view of the overall characteristics of the bearing, the content is preferably 10 to 30% by volume.

It goes without saying that the lead-based bearing alloy, which is a component of the sliding bearing material, has the properties of conventional lead bearing alloys, but it also has the above-mentioned properties of inorganic fibers, such as high-temperature strength, fatigue resistance, load resistance, It is a component that prepares the preconditions for the occurrence of compatibility, etc., and compensates for the drawbacks of inorganic fibers.

[pb] enters into the minute gaps between the inorganic fibers and holds the fibers during 7RM production. This prevents the fibers from falling off on the sliding surface. Further, such action of PB also contributes to improving the abrasion resistance of the inorganic fibers.

Hereinafter, some of the bearing performances among the effects of the present invention will be explained in detail.

The fatigue resistance of the bearing material according to the present invention is mainly caused by the inorganic fibers supporting the dynamic load from the shaft.

In general, inorganic fibers have high strength and are difficult to deform, while lead alloys have low strength and are easily deformable. Therefore, the inorganic fibers of the sliding bearing material of the present invention tend to have higher fatigue resistance than ordinary PB bearing alloys. However, when the inorganic fiber receives a load from the shaft, it deforms as if sinking into the lead alloy, so the high strength of the fiber itself cannot be used as it is for fatigue resistance, and the deformation behavior of the lead alloy greatly affects fatigue resistance. This point is also related to high-temperature strength and can prevent the flow of the lead alloy at high temperatures as much as possible, contributing to improved bearing performance, such as load resistance at high temperatures. In this case, the Sn content is 13% or less by weight based on the lead alloy.
, 18% or less sb, 5% or less Cu, 3% or less As
, 2% or less of one or more alkali metals, the lead alloy holds the inorganic fibers even more strongly against the axis. Preferably, Sn is 0.8-1.8% and sb is 10-10%.
16%, Cu 0.3-2%, As 0.5-1.5%
It is good to have a range of .

In terms of fatigue resistance, more preferable inorganic fibers are A1□0,,S
iC, is 2Ti60.3, and its preferred amount is 3
It is 0 to 50% by volume.

Compatibility In the sliding bearing alloy according to the present invention, conformability is achieved by the action of the inorganic fibers flattening the mating shaft and the action of the lead alloy being flattened by the mating shaft.

In the sliding bearing material 1 of the present invention conceptually shown in FIG. As the lead alloy 2 is scraped away by the mating shaft 4, the sliding surfaces of the two become familiar and a good oil film pressure 5 is formed.

Embeddability The property of not roughening the shaft by embedding fragments or fallen inorganic fibers caused by wear of the shaft or bearing in the bearing (embeddability) is achieved by using a lead alloy in the suberi bearing material according to the present invention. be done.

Such embeddability is extremely important when FRM is used in bearings. In other words, in FRM, it is inevitable that fibers will fall off. The fibers that have fallen off are quite long, and the inorganic fibers are extremely hard, both of which can cause significant damage to the shaft. Therefore, in order to use FRM as a bearing, it is important to find a way to make it embeddable. The inventors observed the surface of the bearing after the sliding test and found that the inorganic fibers, etc. that had fallen off were stuck to the lead alloy surface, and that when the load was particularly high, the inorganic fibers were buried and the surface It was discovered that soft metal chips were covering the surface. Therefore, it was found that lead has the function of embedding the inorganic fibers that have fallen off and the function of embedding the inorganic fibers held by the lead.

These effects are thought to contribute to significantly improving bearing performance under high loads (particularly wear resistance, seizure resistance, and fatigue resistance) compared to conventional lead-based bearing alloys. The preferred amount of lead alloy in terms of embeddability is 95 to 80%, and the preferred types of inorganic fibers are S i C,
S i, N4. The fibers have a small diameter, such as Teha fiber or K2Ti6O13.

Seizure Resistance Seizure resistance here refers to the property of the material determined by the surface pressure at which seizure occurs when the load is increased in the laboratory.
(hard to occur) does not refer to the properties of the material. In the slip bearing alloy according to the present invention, a sliding surface is stably formed, and metal contact that causes seizure is effectively prevented. In other words, the coefficient of friction of the inorganic fibers, etc. present on the sliding surface is difficult to change, so the sliding surface is stable, and the inorganic fibers that bend come into contact with the shaft, reducing the area where the lead alloy contacts the shaft. Therefore, metal contact is effectively prevented. On the other hand, inorganic fibers tend to fall off the bearings, so the amount used is 50%.
Limited to capacity%.

If this amount is exceeded, the inorganic fibers that have fallen off will damage the other shaft, and the other shaft will cause the inorganic fibers to fall off again, creating a vicious cycle. In terms of seizure resistance, the amount of lead alloy is preferably 95 to 70% by volume, more preferably 95 to 82% by volume.

A preferred type of lead alloy is a pb or Pb-3n alloy, for example, Pb-15Sb-1,2Sn-0
, 5Cu-IAs. Composition: 18% or less Sb
.

7% or less Sn, 5% or less Cu, 3% or less As, etc. may be added to pb as necessary. Preferably, sb is 10% or less.
~16%, Sn 0.8-1.8%, Cu 0.3-2
% and As are preferably in the range of 0.5 to 1.5%. Preferred types of inorganic fibers include SiC, S 13N4.
KzTlio□1, and A1□03.

Indigo! Wear resistance, which is one of the characteristics of sliding bearings, generally refers to the property that the bearing material is difficult to wear after it has been broken in, but in the sliding bearing material of the present invention, a good lubricating film is formed. Excellent wear resistance is achieved by fiber-reinforced lead alloy. Conventional PB-based plain bearing alloys have the drawback of being extremely susceptible to wear because they do not exhibit reinforcement or conformability with inorganic fibers, but the present invention does not have such drawbacks.

Note that when the inorganic fibers fall off, the fiber pieces tend to wear out the bearing, but the above-mentioned embeddability reduces the wear. The preferred amount of lead alloy for wear resistance is 80
~50% by volume, and the preferred type of lead alloy is PB or Pb-3n alloy as described in the section on seizure resistance.

Preferred types of inorganic fibers are A1□03. A1□○
, -5in2°SiC.

Resistance 411 Corrosion resistance here refers to the ability of a slip bearing to withstand changes in color or chemical deterioration due to contact with high-temperature lubricating oil, resulting in an increase or decrease in weight. It is not resistant to lubricating oil considering the conditions it will be exposed to. In the sliding bearing material according to the present invention, almost only the lead alloy corrodes. This is assumed based on experimental results showing that the more inorganic fibers etc. are included, the less the amount of corrosion or discoloration occurs. Regardless of the mechanism, corrosion resistance is slightly improved by using inorganic fibers. Note that even if lead alloys have the same composition, if many pores are formed during FRM, the corrosion resistance will deteriorate. Therefore, it is important to bring the lead alloy and inorganic fibers into even contact.

P used in the present invention is a component that significantly improves corrosion resistance. The action of P is thought to be both to make the FRM homogeneous by improving the flow of the lead alloy and to reduce the chemical reactivity of the lead alloy with the lubricating oil. If the P content is less than 0.05% by weight, the effect will be small, and if the P content exceeds 1% by weight,
Adding more than this does not significantly increase performance and is economically disadvantageous, so when adding P to improve corrosion resistance, P
The content was set to 0.05 to 1% by weight.

On the other hand, when considering the effect of hot water flow on Pb, in terms of high temperature strength, it works equally or advantageously in combination with Pb base bearing alloy inorganic fibers, etc. This is thought to be because the addition of P substantially improved the ability to retain inorganic fibers, etc., which had an advantageous effect on bearing performance at high temperatures. Also from this point of view, it is preferable that the content of P is 1% by weight or less.

Here, the effects of the alloying element and matrix in a conventional PB-based plain bearing alloy will be compared with the effects of inorganic fibers and the like and the matrix (lead alloy) in the present invention.

I) C conventionally used as an alloying element in b-based alloys
U, Sb, Sn, Na, Li, etc. are widely used, although there are differences in whether they directly become a dispersed phase or contribute to the formation of a dispersed precipitated phase; in a sense, they are inorganic in that they have a dispersing effect. Same as fiber etc.

However, if we evaluate the effect from the viewpoint of whether it is sufficient to withstand high engine output and high-temperature lubricating oil, the conventional Pb-based bearing base metal in Japan is almost entirely made of Kelmet and A1-based alloys. As clearly shown by the fact that alloying elements were substituted, dispersion strengthening by alloying elements was not sufficient. This is because dispersion strengthening by alloying elements also affects the pb71-lix, resulting in drawbacks such as embrittlement and reduced strength.

Inorganic fibers naturally affect the strength of the matrix, but like the dispersed precipitated alloy phase that is formed separately from the matrix or at the same time as the matrix is formed,
Since inorganic fibers do not have an inherent relationship with the matrix, the degree of influence is small.

This is not only an advantage, but also a disadvantage that inorganic fibers etc. easily fall off, but this disadvantage at least impairs the essence of PB, which is soft and has good conformability, and may cause the PBB alloy to become brittle. It's not something. Therefore, compared to alloying elements, inorganic fibers and the like can strengthen the Berry bearing alloy while taking advantage of the inherent good properties of PB.

EXAMPLE Tests were conducted on the test materials shown in Table 1 under the following conditions.

Fatigue test test machine... Soda type dynamic load tester Rotation speed = 2800-3500 rpm Lubricating oil -8AEIOW-30 Oil supply temperature...120℃ Shaft material...555G quenched shaft roughness...0 .4~0.6μm Rz wear test Same conditions as fatigue test, but with shaft roughness of 0.8~1.2μ
Change to mR7 and apply 10 at constant pressure of 500kg/cm" surface pressure.
I applied the load seven times.

Corrosion resistance test 200H in lubricating oil (SAEIOW-30) at 160℃
r boiled in oil.

Seizure test machine...Journal type seize test machine mating material shaft...
FCD70 Lubricating oil...5AEIOW-30 Shaft surface roughness...0.4 to 0.6μm Rz lubricating oil temperature...140±2.5℃ Shaft rotation speed...11000rp Shaft diameter...52mm Shaft hardness -Hv 200-300 Load -50kg/cm2/Increased by the same amount at 30m1n intervals Bearing roughness...1 to 1.8μm Rz bearing diameter...
・52mm Test results are shown in Table 1.

An example of the method for manufacturing a bearing material according to the present invention will be described below.

First, a backing steel plate having a normal thickness is cut into a predetermined width and length, preheated to 210 to 250°C, passed through a tin bath, and 1 to 2 μm of tin is deposited on the surface. Next, a steel backing plate is placed in a mold, and a preformed inorganic fiber or the like having approximately the same width and length as the steel backing plate is placed thereon. The thickness of this molded body is usually 3 to 10 mm. The direction of each fiber in the molded body may be arbitrary, such as unidirectional or random. Further, the size of each fiber is usually 0.1 to 20 μm in diameter. After the fiber molded body is placed in the mold, a molten lead alloy is poured into the mold at a temperature of 430 to 550°C, and a pressure of 200 to 1000 kg/cm2 is applied to the molten metal to perform pressure casting. .

The cast alloy is removed from the mold together with the backing steel plate, bent into a half-metal shape, and finished by cutting the surface.

In this manufacturing method, attaching tin to the surface of the backing steel plate that is the base material improves the adhesion between the base material and the PBB bearing alloy layer, and maintains the long-term performance as a bearing material.
Particularly contributes to fatigue resistance.

In order to outperform Kelmet and aluminum-based bearing alloys, PB-based bearing alloy J-, which is a plain bearing material according to the present invention, is used as an overlay of Kelmet and the like.

That is, Kelmet and aluminum-based bearing alloys may be used as a base material, and the PBB bearing alloy layer of the present invention may be provided on this base material. In this method, instead of using a backing steel plate as a base material, the base material is a bimetallic material having an aluminum alloy on the backing steel plate or a bimetallic material having a copper alloy on the backing steel plate. At this time, the thickness of the PBB bearing alloy layer is 5 to 50 mm when the processing as a plain bearing is completed.
The thickness is preferably 0 μm, preferably 10 to 200 μm.

Although an example of a manufacturing method using a pressure casting method is shown here, it may also be manufactured using electroplating, dispersion plating, or the like.

〔Effect of the invention〕

The properties of the bearing material according to the present invention are slightly inferior to those of Kelmet and aluminum-based bearing alloys in terms of fatigue resistance and load carrying capacity, but are superior to other properties.

In particular, it is superior to Kelmet and aluminum bearing alloys in terms of conformability, embeddability, and seizure resistance.

In addition, the fatigue resistance, load resistance, corrosion resistance, and seizure resistance of the bearing material according to the present invention are significantly superior to those of conventional white metal bimetal alloys, and it has excellent conformability.

The buryability is almost the same.

Thus, it is of great significance to provide a bimetallic alloy that is superior to conventional white metal bimetallic alloys and a bearing material that is expected to be fully competitive with Kelmet and aluminum bearing alloys.

Moreover, when used as an overlay, the excellent conformability and embeddability are suitably utilized.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram of the shaft and bearing. 1...bearing material, 2...pb base bearing alloy 3...Inorganic fibers, etc. 4...axis, 5...Oil film pressure, 6...Base material.

Claims (1)

[Claims] 1. In a bearing material comprising a Pb-based bearing alloy layer provided on a base material, the Pb-based bearing alloy contains 5 to 50% of the total content of the Pb-based bearing alloy layer.
Capacity% Al_2O_3, Al_2O_3-SiO_2
, SiO_2, SiC, BN, Si_3N_4, K_2
A bearing material characterized in that fibers or whiskers selected from Ti_6O_1_3 etc. are dispersed and composited. 2. The bearing material according to claim 1, wherein the base material is a backing steel plate. 3. The bearing material according to claim 1, wherein the base material is a bimetallic material comprising an aluminum alloy or a copper alloy on a backing steel plate. 4. A bearing material according to any one of claims 1 to 3, characterized in that the Pb-based bearing alloy contains 0.05 to 1% by weight of P.