WO2014157650A1

WO2014157650A1 - Aluminum alloy, slide bearing, and slide bearing manufacturing method

Info

Publication number: WO2014157650A1
Application number: PCT/JP2014/059234
Authority: WO
Inventors: 桂己山本
Original assignee: 大豊工業株式会社
Priority date: 2013-03-29
Filing date: 2014-03-28
Publication date: 2014-10-02

Abstract

In the present invention, an aluminum alloy contains 1-20 % by mass of Sn, 0.5-12 % by mass of Si, 0.05-1.5 % by mass of Fe, and Al. The aluminum alloy has Si particles dispersed in an Al matrix, and an Fe phase dispersed in the Al matrix.

Description

Aluminum alloy, slide bearing, and method of manufacturing slide bearing

The present invention relates to an aluminum alloy, a slide bearing, and a method of manufacturing the slide bearing.

Aluminum alloys are widely used as bearing alloys in sliding bearings of engines of automobiles and industrial machines (Non-patent Document 1). Although there are various properties required for bearings, improvements have been attempted in terms of both materials and structures in order to achieve the required properties.

The improvement of the material is, first, the improvement of the bearing alloy itself. As an aluminum alloy for a slide bearing, for example, an A-Si-Sn-based alloy to which Si and Sn are added is known (Non-Patent Document 2). In aluminum alloys used in bearings, Fe is generally treated as an impurity. However, Patent Documents 1 to 4 disclose techniques of adding Fe to an aluminum alloy.

Secondly, as a material improvement, there is known a technique of providing an overlay layer on a bearing alloy layer (lining layer) (Patent Documents 5 to 7 and Non-patent Documents 3 to 4).

As an improvement of the structure, there is known a technique of providing a groove on the sliding surface of the bearing (Patent Document 8 and Non-Patent Document 5).

Japanese Patent Application Laid-Open No. 62-37337 Patent No. 3207863 specification Japanese Patent Publication No. 62-42983 Patent No. 3857503 Specification Japanese Patent Application Laid-Open No. 4-83914 JP 2002-61652 A JP 2004-263727 A JP-A-7-259860

On the other hand, the present invention provides a further improved aluminum alloy, slide bearing, and slide bearing.

One embodiment of the present invention contains 1 to 20% by mass of Sn, 0.5 to 12% by mass of Si, 0.05 to 1.5% by mass of Fe, and Al, and is dispersed in an Al matrix. The present invention provides an aluminum alloy having Si particles and an Fe phase dispersed in an Al matrix.

The aluminum alloy may contain 0.3% by mass or more of Fe.

In the Fe phase, Al is taken in from the Al matrix, and the concentration of Al is highest at the interface between the Fe phase and the Al matrix, and may decrease toward the inside of the Fe phase.

The aluminum alloy may contain, as additive elements, at least one of 0.5% by mass or less of Cr and 3% by mass or less of Cu.

In the Fe phase, the additive element is taken in from the Al matrix, and the concentration of the additive element may be highest at the interface between the Fe phase and the Al matrix and may be lowered toward the inside of the Fe phase.

This aluminum alloy contains 8% by mass or less of at least one of Mg, Ag, and Zn, and 0.5% by mass or less of at least one of Zr, Mn, V, Sc, Li, and Ni. And, as an unavoidable impurity, Ti and B may be contained in a total amount of 0.5% by mass or less.

The aluminum alloy may contain 5% by mass or more of Sn.

In this aluminum alloy, five or more Si particles having a major axis dimension of 5 to 40 μm may be present per section of 3.56 × 10 ⁻² mm ² .

The equivalent circular diameter of the Si particles may be 2 to 15 μm, and the number of Si particles having a equivalent circular diameter of 4 μm or more may be 20% or more.

Further, the present invention provides a slide bearing having a lining layer formed of any of the above aluminum alloys and a back metal formed of an Fe-based material.

The surface of the lining layer in contact with the other axis may be cut.

Furthermore, the present invention has a lining layer formed of any of the above aluminum alloys or an Al—Sn-based alloy containing 1 to 20 mass% of Sn, and a back metal formed of an Fe-based material, An Al--Fe diffusion layer and a brazing surface of Sn are formed at the interface between the lining layer and the back metal, and the lining layer has a plurality of recesses formed in a dispersed manner in the bonding surface with the back metal. The present invention provides a slide bearing in which a part of Sn present at the interface is buried in the recess.

The lining layer may contain 0.2 to 1.5% by mass or less of Fe, and may have a dispersed Fe phase, and the recess may be formed by mechanically scraping the surface of the lining layer. Good.

The recess may be formed by shot blasting.

The recess may be formed by laser processing.

Furthermore, the present invention provides an Al—Sn alloy containing 1 to 20% by mass of Sn and 0.2 to 1.5% by mass of Fe or 5 to 20% by mass of Sn, 0.5 to 12% by mass of Si, And roughening the surface of a rolled sheet of an Al—Sn—Si alloy containing 0.2 to 1.5% by mass of Fe to a roughness of 1 to 5 μm JIS (Ra) and roughening; A method of manufacturing a slide bearing, comprising the steps of pressing the rolled plate and the Fe-based metal backplate by rolling after the roughening, and annealing at 250 to 500 ° C. after the rolling. .

Furthermore, the present invention comprises a lining layer and an overlay layer formed on the lining layer, wherein the lining layer comprises 1 to 20% by mass of Sn and 0.5 to 12% by mass of Si. The overlay layer contains 0.20% by mass or more and 2.0% by mass or less of Fe and Al, and the overlay layer contains at least one of MoS ₂ , PTFE, graphite, WS ₂ , h-BN, and Sb ₂ O ₃ A slide bearing comprising: a solid lubricant containing a seed; and a binder resin containing at least one of polyamideimide resin, polyimide resin, phenol resin, polyacetal resin, polyetheretherketone resin, polyphenylene sulfide resin, and epoxy resin Do.

The content of the solid lubricant in the overlay layer may be 30 to 70% by volume.

The overlay layer is made of SiC, Al ₂ O ₃ , TiN, AIN, CrO ₂ , Si ₃ N ₄ ,
It may further include a hard substance containing at least one of ZrO ₂ , Fe ₃ P, Fe ₂ O ₃ , and FeO.

The content of the hard material in the overlay layer may be 0.1 to 5% by mass.

The lining layer may be formed by cold rolling a continuous cast plate.

The lining layer may further include at least one of (a) to (d). (A) at least one of at least 0.5% by mass of Cr and at most 3% by mass of Cu, (b) at least one of Mg, Ag and Zn in a total amount of at most 8% by mass, (c) Zr, 0.5 mass% or less in total of at least one or more of Mn, V, Sc, Li and Ni, and (d) 0.5 mass% or less in total of at least one of Ti and B as unavoidable impurities.

The slide bearing may be formed of an Fe-based alloy and may further include a back metal press-contacted to the lining layer.

The surface of the lining layer in contact with the other axis may be cut.

The figure which shows the ideal surface profile of a ditch. The figure which illustrates the actual surface profile of a slot. EPMA color mapping picture of aluminum alloy. The sketch figure of the pattern which shows Al concentration among the photographs of FIG. The sketch figure of the pattern which shows Fe concentration among the photographs of FIG. The sketch figure of the pattern which shows Si concentration among the photographs of FIG. The schematic diagram of Al and Fe concentration profile of Fe phase. The figure which shows Fe content dependence of the surface roughness of aluminum alloy. The figure which shows the sweating phenomenon of aluminum alloy. Typical sectional drawing of the brazing contact surface of aluminum alloy rolling board and a metal back. SEI of aluminum alloy rolled sheet with surface cut. The schematic diagram which shows the cross-section structure of an aluminum alloy rolled sheet and a steel back metal. The schematic diagram explaining burying of molten Sn. The figure which illustrates the structure of the bearing 1.

DESCRIPTION OF SYMBOLS 1 ... Bearing, 11 ... Back metal, 12 ... Lining layer, 16 ... Sn flow, 20 ... Al matrix, 21 ... Fe phase, 22 ... Si phase, 25 ... Sn phase, 28 ... Aluminum alloy rolling board, 30 ... Back metal, 40 ... Sn layer

Hereinafter, some embodiments of the present invention will be described. The aluminum alloy and slide bearing according to the following embodiments can be used for half bearings, bushings, thrust washers and the like. Of the embodiments described below, two or more may be used in combination.

FIG. 14 is a view illustrating the structure of the bearing 1 according to an embodiment. The bearing 1 is a slide bearing and has a back metal 11 and a lining layer 12. The back metal 11 is a layer for reinforcing the mechanical strength of the lining layer 12. The back metal 11 is formed of, for example, steel. The lining layer 12 is provided along the sliding surface (surface in contact with the shaft) of the bearing, and has characteristics as a bearing, for example, friction characteristics, seizure resistance, wear resistance, conformability, foreign matter burying ability It is a layer to give characteristics such as robustness) and corrosion resistance. The lining layer 12 is formed of a bearing alloy. In order to prevent adhesion with the shaft, the bearing alloy is prevented from becoming so-called "twist" and a material system different from the shaft is used. In this example, an Al-based alloy (aluminum alloy) is used as a bearing alloy in order to use as a bearing of a shaft formed of steel.

1. First Embodiment 1-1. Overview Grooves may be formed on the surface of the bearing to improve the characteristics of the sliding bearing. For example, when forming a groove by cutting, a cutting edge may be formed on the cutting tool. The constructed cutting edge may form an unintended shape on the bearing surface (i.e., the cutting shape may become unstable). The present embodiment provides a technology capable of obtaining desired characteristics while stabilizing the cutting shape.

The inventors of the present invention conducted intensive studies on an aluminum alloy containing Fe as an effective element, and obtained the following findings.

(1) A boring machine equipped with a sintered diamond tool is used as a cutting tool, for example, for forming an arc-shaped groove (FIG. 1: reference to FIG. 9 of Patent Document 1). However, because the cutting edge is formed on the cutting tool, the targeted height can not be obtained, and a fine roughness occurs on the surface (FIG. 2).

(2) When the amount of Fe is large in the Al-Sn-Si alloy, the formation of the component cutting edge is suppressed, and the cutting shape of the groove is stabilized.

(3) The added Fe reduces the cutting roughness even in a bearing without grooves.

Al-Sn-Si based slide bearings in which massive Si particles are dispersed are mounted, for example, on parts of commercial vehicles. The inventors of the present application conducted research in order to suppress the harmful effect of Fe as an impurity and simultaneously obtain the effect of Si massive particles in an aluminum alloy for bearings, and obtained the following findings.

(4) It is desirable to disperse Si massive particles in an aluminum material having excellent ductility.

(5) The Si massive particles braze the cutting tool, and the aluminum alloy adheres to the formed crucible. Thus, the component cutting edge is formed. This tendency is more pronounced as the particle size of the Si particles is larger and / or the corners are sharper. In addition, it is a problem that Al itself has high affinity with the cutting tool material, and adhesion occurs and it is easy to form a component cutting edge. However, the formation of the component cutting edge can be suppressed by applying the above findings (1) to (3).

1-2. Embodiment 1A
The aluminum alloy according to one embodiment includes 1 to 20% by mass of Sn, 0.5 to 12% by mass of Si, and 0.05 to 2.0% by mass of Fe, with the balance being Al and unavoidable impurities. is there. Here, Si particles and an Fe phase not containing Si are dispersed in the Al matrix. The composition of Fe is preferably 1.5% by mass or less.

In this aluminum alloy, Sn imparts lubricity. When the content of Sn is less than 1% by mass, the lubricity is insufficient. On the other hand, when the content of Sn exceeds 20% by mass, mechanical properties deteriorate due to strength reduction and melting point depression due to the soft Sn phase, and as a result, the wear resistance and the like deteriorate. The preferred Sn content is 2 to 18% by mass.

Si crystallizes as Al-Si eutectic during casting. Thereafter, by rolling the cast plate, the Si particles are finely dispersed in the aluminum matrix to impart wear resistance. That is, the Si particles do not need to be agglomerated by the method of Patent Document 1 and contribute to wear resistance if they are refined by rolling. The size of the Si particles is not particularly limited, but is preferably 2 μm or more in average particle size and 12 μm or less in maximum particle size. The preferred Si content is 2 to 7% by mass.

FIG. 3 is a diagram illustrating the structure of an aluminum alloy. FIG. 3 shows the result of EPMA color mapping of the concentration of each element in a rolled sheet of Al-12% Sn-3% Si-2% Fe. In addition, this rolling board was manufactured by the below-mentioned method of controlling cooling at the time of casting. Also, since color drawings can not be shown here, photographs in which color mapping is monochrome are shown. The photograph of 3 rows 3 columns is shown by FIG. 3, but arrangement of each element is as Table 1.

Figures 4, 5 and 6 are sketches of the density distribution in EPMA color mapping. The Al matrix 20, the Fe phase 21 and the Si phase 22 are shown in FIGS. If these figures are described by adding the information of the original color mapping, in FIG. 4, the Al concentration of the Al matrix 20 is in the highest state (red). In FIG. 5, the Fe concentration of the Fe phase 21 is distributed from the highest concentration (red) to the low concentration (blue), and extends along the grain boundaries of the Al matrix. In FIG. 5, Al incorporated into the Fe phase 21 is distributed from medium concentration (yellow) to low concentration (blue). The same pattern as that of the Si phase 22 shown in FIG. 6 is also recognized in FIG. 4, and it is understood from this pattern that the Si phase 22 is an Al—Si eutectic. Because the patterns in FIGS. 5 and 6 do not match, the crystallization of the Al—Si eutectic and the Fe phase 21 occurs at different positions.

FIG. 7 is a graph schematically showing changes in Fe concentration and Al concentration of the Fe phase 21a of FIG. 5 in the horizontal direction of the drawing. 4 to 7 and an assumed Al—Fe pseudo binary phase diagram of an Al—Sn—Si—Fe based aluminum alloy. The composition of the aluminum alloy of the present invention is a hypoeutectic composition on the Al rich side with respect to the Al—Fe eutectic point. Therefore, the Fe phase extends along the grain boundaries after Al crystal solidification. Also, after aluminum is crystallized, a concentration profile as shown in FIG. 7 is formed because Fe takes in Sn, Al and the like.

In the present embodiment, the Fe phase is a region where Fe is detected outside the region (Al matrix 20 shown in FIGS. 4 to 6) at which the Al concentration is highest in EPMA analysis. As shown in FIG. 7, the Fe phase incorporating Al will be described based on the phase diagram of the Fe-Al binary system. The Fe side 21P is irregular with the Fe rich side bordering on about 14 mass% of Al. It is a solid solution, and the Al rich side is an ordered solid solution. Furthermore, at 600 ° C. or less, an Fe ₃ Al regular lattice is formed. That is, the basic form of the Fe phase is a solid solution. In the Fe phase 21Q on the Al side, precipitation of Fe occurs because there is no solid solubility of Fe in Al. The center of the Fe phase has a composition close to that of pure iron with a low concentration of Al. In the present invention, it is considered that the detoxification of Fe is due to the Fe phase having the crystal structure as described above. Therefore, bearing performance does not deteriorate even if it contains 1.5% by mass of Fe exceeding the conventional Fe impurity level. Rather, better seizure resistance can be achieved than conventional aluminum alloys. However, if the Fe content exceeds 1.5%, rolling of the aluminum plate becomes difficult.

The aluminum alloy according to the present embodiment may contain 0.5 mass% or less of Cr and 3 mass% or less of at least one additive element of Cu. Cr forms an Al-Cr based intermetallic compound to improve the strength of the aluminum matrix. In addition, the additive element is taken into the Fe phase, and by enhancing the hardness of the Fe phase, the effect of removing the component cutting edge is enhanced. If the content of Cr exceeds 0.5%, it segregates in the aluminum matrix to cause a reduction in the rollability and the like, so the content of Cr is preferably less than 0.5% by mass.

Cu strengthens the matrix of the aluminum alloy and also improves the heat resistance. Cu is also incorporated into the Fe phase to increase its hardness. However, if the addition amount of Cu exceeds 3% by mass, the rolling property decreases to cause cracking or the like during rolling, so the content of Cu is preferably 3% by mass or less.

The Fe phase when the additive elements are Cu and Cr is a Fe—Cu—Cr solid solution phase in which Al, Cu, and Cr form a solid solution in Fe crystals. This phase is lower in hardness than Fe ₃ Al and Fe—Al—Si based intermetallic compounds, but the addition of Cu and Cr increases the toughness and hardness. From these physical properties, the Fe-Cu-Cr phase is particularly excellent in the effect of removing the component edge formed by cutting Al. Specifically, since the chips of Al can be finely discharged, it is possible to avoid the defective cutting surface due to the continuous chips. When the hard phase exists on the surface to be cut of the aluminum alloy, pores and defects occur when the cutting tool breaks the hard phase. However, since the Fe--Cu--Cr phase is excellent in toughness, it is possible to prevent pores and defects.

The aluminum alloy has a total content of at least one of Mg, Ag and Zn of at most 8% by mass, and a total content of at least one of Zr, Mn, V, Sc, Li and Ni of at most 0.5% by mass , May be included. Mg, Ag and Zn provide solid solution strengthening. However, if the total content of these components exceeds 8% by mass, the performance is lowered due to the decrease in toughness due to the formation and precipitation of intermetallic compounds and the crystallization of additional elements. Therefore, the content of Mg, Ag, and Zn is preferably 8% by mass or less. Zr, Mn, V, Sc, Li and Ni provide precipitation strengthening. However, if the total amount exceeds 0.5% by mass, the effect of improving the strength can not be obtained due to coarsening and segregation of precipitated particles, and therefore the content thereof is preferably 0.5% by mass or less. Hereinafter, Mg, Ag, Zn, Zr, Mn, V, Sc, Li, and Ni are referred to as "additional elements". Among the additional elements, Mn, Ni, Zr, and V are widely used as alloy elements of Fe, but due to their small contents, only trace amounts or less can be taken into the Fe phase.

The aluminum alloy may contain a small amount of impurities such as Pb, In, or Bi, which are inevitably produced from the metal or scrap raw material, in addition to the above-described basic components and additive elements. In addition, Ti and B may be used as a refining agent for Al crystal grains, but in the aluminum alloy of this embodiment, fine crystal grains are not related to Fe phase formation, so the total amount is 0.5 mass% or less Ti and B are acceptable as impurities.

In this embodiment, a molten aluminum alloy having the above composition is poured into a continuous casting mold to form a continuous cast plate having a thickness of 3 to 20 mm. At that time, a Si-free Fe phase can be formed by cooling the casting plate solidified from the molten metal temperature in the mold at a temperature range of 850 to 300 ° C. at a speed of 2000 to 5000 ° C./min. In addition, by slowing the cooling rate, it is possible to increase the uptake amount of Al and the additive element.

A sliding bearing can be obtained by pressure-bonding this aluminum alloy with a low carbon steel (an example of an Fe-based alloy) such as SPCC or SPCH, and further forming it. In this slide bearing, Fe is dispersed as an Fe phase in an Al matrix to stabilize cutting. When the aluminum alloy is cut with a cutting tool, the aluminum adheres to the surface of the cutting tool to form a component cutting edge, so that the cutting roughness of the slide bearing surface becomes rough. Regarding hardness such as Fe phase, cutting tools such as high speed steel, diamond tools etc (hardness Hv 1500 or higher)> Si particles (hardness about Hv 1000)> Fe-Al based intermetallic compound (hardness Hv 700 or higher)> Fe phase ( Since there is a relationship of pure iron (Hv 200)) to Al, and an Fe phase incorporating an additive element (Hv 400)> Al alloy phase (Hv = 30 to 90), the Fe phase can scrape off the aluminum alloy of the component cutting edge. On the other hand, Si particles and the like may have a small difference from the hardness of the cutting tool material, so that the cutting tool may be brazed. As a result, since the roughened tool scrapes off the aluminum alloy, the sliding roughness of the sliding bearing becomes rough.

1-3. Embodiment 1B
An aluminum alloy according to another embodiment contains 1 to 20% by mass of Sn, 0.5 to 12% by mass of Si, and 0.05 to 1.5% by mass of Fe, with the balance being Al and unavoidable impurities. It is. The aluminum alloy may contain additional elements and / or additional elements. Here, Si particles and an Fe phase are dispersed in the Al matrix. Furthermore, in this aluminum alloy, Si particles having a major axis dimension of 5 to 40 μm are present 5 or more per 3.56 × 10 ⁻² mm ² .

This aluminum alloy is obtained by annealing at 300 to 550 ° C. before pressure contact with the back metal. By roughening the Si particles, it is possible to smooth the unevenness of the mating shaft, in particular, the surface of the casting shaft. The Si particles can also be coarsened by similarly annealing at 300 to 550 ° C. for solid bearings not in pressure contact with the backing metal. The Fe phase and the additive and / or additional elements are as described above.

In this aluminum alloy, it is preferable that the coarsened Si particles have a circle equivalent diameter of 2 to 15 μm, and Si particles having a circle equivalent diameter of 4 μm or more be 20% or more in number ratio.

1-4. Experimental Example 1-4-1. Embodiment 1A
FIG. 8 is a view showing the Fe composition dependency of the surface roughness. For measurement of the surface roughness, an aluminum alloy having a composition of Al-3 to 15% by mass Sn-2 to 7% by mass Si-0.1 to 5% by mass Fe was used. An aluminum alloy of this composition was cast under the conditions described above. The surface roughness (Rz JIS, Ra, and Rmax) was measured when the surface of the rolled plate (as roll) was cut with a (lathe) tool under a cutting condition of 1 m / s. From this figure, it can be seen that the surface roughness decreases as the amount of Fe increases, despite the fact that the tool and cutting conditions are constant. From visual observation of the cutting edge surface after cutting, it was also found that the larger the amount of Fe, the smaller the cutting edge. From these experimental results, as the amount of Fe is larger, preferably 0.3% by mass or more, the material to be cut scrapes away the component cutting edge, and the roughness of the material to be cut becomes smaller. In the past, there was a component cutting edge formation as the cause of not being able to obtain the intended roughness, but according to this embodiment, this can be solved to stabilize cutting.

In the slide bearing using the aluminum alloy according to the present embodiment, the surface in contact with the mating shaft preferably has Rz JIS = 0.5 to 5 μm, Ra = 0.1 to 1.8 μm, and Rmax = 0.5 to 6 μm. It is cut in the range of.

Tables 2 and 3 show the compositions and bearing performances of Experimental Examples 1 to 12. Among these experimental examples, experimental examples 1 to 8 will be described as examples, and experimental examples 9 to 12 will be described as comparative examples. An aluminum alloy having these compositions was continuously cast into a 15 mm thick plate with controlled cooling rate as described above. However, for Comparative Examples 9 to 12, casting was performed at a normal slow cooling rate without controlling the cooling rate in the temperature range of 850 to 300 ° C. as described above. The obtained cast thin sheet was cold-rolled and then pressed against a back metal (SPCC steel plate) to obtain a bimetal.

These bimetallic materials were processed into bearings and performance tests were conducted under the following conditions. The test results are shown in Table 3.

Fatigue resistance test Tester: Reciprocating load tester Rotational speed: 2000 to 3000 r. p. m
Test temperature (bearing back surface temperature): 160 ° C
Counterpart material: S55C Induction hardened Lubricant: CF-4 10W-30

Seizure resistance test Tester: Static load tester Rotational speed: 1300 to 8000 r. p. m
Test temperature (refueling temperature): 160 to 180 ° C
Load: 5MPa gradually increase Counterpart material: S55C Induction hardening Lubricant: SN 0W-20

Abrasion resistance test Tester: Load abrasion tester Rotational speed: 0 to 1000 r. p. m
Test temperature (refueling temperature): 50 to 80 ° C
Counterpart material: S55C Induction hardened Lubricant: SN 0W-20

In Table 3, “number” is the number of Si particles having a major axis dimension of 5 to 40 μm per 3.56 × 10 ⁻² mm ² . The unit of average particle size is μm. The unit of fatigue surface pressure and seizing surface pressure is MPa. The unit of the amount of wear is μm.

Although Example 2 and Comparative Example 9 have almost the same Si and Sn compositions, the former is superior in the bearing performance to the latter despite the large amount of Fe. Similar relationships are observed for Example 1 and Comparative Example 10 and for Example 5 and Comparative Example 11. In addition, although the other examples contain high concentration of Fe, the bearing performance is good.

1-4-2. Embodiment 1B
Table 4 shows the compositions and bearing performances of Experimental Examples 13-15. Aluminum alloys having these compositions were cast and rolled as in Example 1. Annealed at 530 ° C. for 6 hours between casting and rolling. After annealing, the aluminum alloy was pressed against the back plate (SPCC steel plate) in the middle of rolling. Table 4 shows the results of measuring the bearing performance in the same manner as Example 1. Table 5 shows the surface roughness after the cutting test. The cutting test was conducted under the condition of 1 m / sec using a cutting tool. In Table 4, "dimension" indicates a circle equivalent diameter [μm]. "Percentage" is the number proportion of particles having a circle equivalent diameter of 4 μm or more in the whole. In Experimental Examples 13 to 15 in Table 4, five or more Si particles were present per 3.56 × 10 ⁻² mm ² .

1-5. Effects of the Embodiment In the aluminum alloy according to the present embodiment, Fe is present as an Fe phase at the grain boundaries of the aluminum crystal, and is rendered harmless. Therefore, the sliding characteristics are improved even if the composition is the same as that of the conventional alloy. Further, even an aluminum alloy containing 0.3% or more of Fe far exceeding the conventional impurity content level has good sliding characteristics. Al incorporated into the Fe phase strengthens the Fe phase and improves the sliding characteristics.

According to the present embodiment, the bearing performance is excellent in spite of containing high concentration of Fe. Furthermore, the finish roughness with high accuracy can be obtained.

2. Second Embodiment 2-1. Overview FIG. 9 is a diagram showing the perspiration phenomenon in an Al—Sn alloy. The inventors of the present invention have found that when the Al—Sn alloy rolled sheet is heated to the annealing temperature, sweating of the Sn phase occurs. Here, “sweat” of the Sn phase refers to a phenomenon in which Sn having a low melting point melts from the alloy phase of the matrix and spouts (spills out) on the surface of the alloy plate. In FIG. 9, Sn particles exist on the surface of the Al—Sn alloy rolled sheet. The diameter of the Sn particles is about 100 to 200 μm. The portion (most part on the upper side of the figure) other than the Al—Sn alloy rolled sheet and Sn particles is in a state where there is no metal layer or the like. The Sn particles formed on the surface are, for example, several to several hundreds per 10 mm in length of the Al—Sn alloy rolled sheet.

Based on this finding, in the bimetal pressure welding process, molten Sn temporarily spouts locally from the Al—Sn-based aluminum alloy rolled sheet, and then the molten Sn phase is stretched on the bonding surface of the bimetal, and locally It is considered that so-called "brazing" is performed. In this process, it is considered that a bonding interface is formed by the Sn phase, or the molten Sn and the Fe of the back metal react to form an Fe-Sn based intermetallic compound. In the case of bimetals, Al-Fe diffusion bonding should be caused preferentially. Since the oxide film on the surface of the rolled Al-Sn alloy interferes with the bonding, the oxide film is removed by a wire brush or the like.

Based on the above findings, the inventors of the present application have conceived that the adhesion between the back metal and the alloy layer can be improved by suppressing the stretching of molten Sn at the interface between the back metal and the alloy layer. Specifically, it was conceived that, by forming a recess in an aluminum alloy rolled sheet and storing the molten Sn in the recess, it is possible to suppress the stretching of the molten Sn and reduce the contact area between Fe and Sn.

In order to roughen the joining surface of the aluminum alloy rolled sheet, there is a method of strengthening machining such as a wire brush. However, if the roughness is made too rough, the true contact area of both metal plates may be reduced, resulting in a decrease in the adhesion strength of the bimetal.

The object of the present embodiment is to increase the strength of the bimetal in a slide bearing produced by press-contacting and annealing an Al—Sn-based or Al—Sn—Si-based alloy rolled sheet and an Fe-based back metal.

The slide bearing according to the present embodiment includes an Fe-based back metal and an alloy layer pressed against the back metal. The alloy layer is formed of an Al—Sn-based alloy containing 1 to 20% by mass of Sn, or an Al—Sn—Si-based alloy containing 5 to 20% by mass of Sn and 0.5 to 12% by mass of Si. ing. The alloy layer contains 0.2 to 1.5% by mass of Fe. The surface of the rolled sheet (pressure contact planned surface) is roughened to a roughness of 1 to 5 μm JIS (Ra). Roughening is performed by mechanically scraping the surface. The rolled sheet and back plate of this alloy are cold rolled. After cold rolling, the alloy layer and the back metal are joined by annealing at 250 to 500.degree. A pressure contact surface including an Al—Fe diffusion layer and a solder contact surface of Sn is formed between the alloy layer and the back metal. A large number of recesses are dispersedly formed on the bonding surface of the rolled sheet, and a part of Sn present in the brazing surface is buried in the recesses.

In an aluminum alloy, Sn imparts lubricity. If the content of Sn is less than 1% by mass in the Al--Sn system and less than 5% by mass in the Al--Sn--Si system, the seizure resistance decreases. On the other hand, when the content of Sn exceeds 20% by mass, mechanical properties deteriorate due to strength reduction and melting point depression due to the soft Sn phase, and as a result, the wear resistance and the like are deteriorated. The content of Sn is preferably 2 to 18% by mass.

The Si is as described in the first embodiment.

The aluminum alloy according to the present embodiment is an Al—Sn-based or Al—Sn—Si-based alloy used industrially. The aluminum alloy may contain known additive elements in addition to Sn and Si. Although the added elements can improve the bearing performance, the occurrence of Sn sweating is a phenomenon unique to Al-Sn and Al-Sn-Si alloys.

The additive element may include at least one of Cr and Cu, and the additional element may include at least one of Mg, Ag, Zn, Zr, Mn, V, Sc, Li, and Ni. Furthermore, the aluminum alloy may contain a small amount of impurities such as Pb, In, and Bi. These elements are as described in the first embodiment.

The thickness of the aluminum alloy rolled sheet is not particularly limited, and for example, one having a thickness of 50 μm to 2 mm can be used. For example, a low carbon steel plate such as SPCC can be used as the backing steel plate. The thickness of the backing steel plate is not particularly limited, and for example, one having a thickness of 0.5 mm to 4 mm can be used.

In the slide bearing according to the present embodiment, a rolled plate of an aluminum alloy (Al-Sn alloy or Al-Sn-Si alloy) is broadly classified by pressure welding from the viewpoint of welding, and Al-Fe diffusion bonding and Sn brazing from the welding phenomenon. It is joined to the steel back metal by

FIG. 10 is a view for explaining the bonding of the back metal and the rolled alloy sheet according to the present embodiment. Here, an example is shown in which the aluminum alloy rolled plate 28 and the back metal 30 are joined. Back metal 30 is formed of steel. On the surface of the aluminum alloy rolling plate 28, minute recesses (minute irregularities) 28a and recesses 28b are formed. The minute recesses 28 a are formed by a wire brush or the like. The recess 28 b is formed by shot blasting or laser processing. Although only one recess 28 b is shown in FIG. 10, a plurality of recesses 28 b are formed on the surface of the aluminum alloy rolled plate 28. They are formed apart from one another, ie distributed. An Sn layer 40 is formed at the interface between the aluminum alloy rolled plate 28 and the back metal 30. The Sn layer 40 is a layer in which Sn in the aluminum alloy rolled sheet melts and exudes to the interface. The aluminum alloy rolled plate 28 and the back metal 30 are brazed by the Sn layer 40. A part of the lower part (the aluminum alloy rolling plate 28 side) of the Sn layer 40 is buried in the recess 28 b. Therefore, the reaction with the back metal 30 hardly occurs, and the formation of the Fe--Sn intermetallic compound is suppressed. In addition, the mechanism of burying will be described later.

When forming the recesses 28b by shot blasting, it is preferable to project, for example, particles of about 0.3 to 2.5 mm in diameter downward from above the aluminum alloy rolled sheet at a speed of 10 to 200 m / sec. For the particles, a material having a hardness higher than that of aluminum, for example, a cut wire steel wire, SiC particles or the like is used.

When the recess 28b is formed using a laser, for example, a pulse laser (output 5 to 100 W) such as a Yb fiber laser is used. It is preferable to form a recess having a depth of about 3 to 15 μm by scanning a laser beam on the aluminum alloy rolling plate.

It is an advantage that the recess according to the present embodiment is not continuous as the recess formed by the cutting tool. It is easy to find a place where Sn is not buried in continuous recesses. If there is a place where Sn is not buried, it causes the reduction of the pressure contact strength. The recesses of the present invention are dispersed, but when observed microscopically, there are a large number of sweating positions. For example, when grid particles are made to collide with the entire surface of a rolling plate by shot blasting according to a usual method, A recess is formed.

Details will be described below. A roughened surface of 1 to 5 μm JIS (Ra) is formed by machining the surface of the aluminum alloy rolled sheet (pressure contact surface with the steel back metal). The roughness of the aluminum alloy rolled sheet is measured in the width direction of the rolled sheet. The machining according to the present invention is performed, for example, by cutting with a cutting tool or grinding with abrasive grains. The fine convex portion at the end of the roughened surface is crushed by the surface of the steel material during roll pressure welding, so Fe-Al diffusion is likely to occur in the next annealing step (hereinafter this effect is referred to as “diffusion promotion effect” Called). Furthermore, when the roughened surface is formed, the Fe phase is scraped off to realize the Sn burying effect (details will be described later). If the roughness formed by this machining is less than 0.5 μm, the diffusion promoting effect is insufficient, and furthermore, the Sn burying effect is also insufficient because the Fe phase is not sufficiently scraped off. On the other hand, when the roughness exceeds 5 μm, the groove on the roughened surface becomes too deep, so the diffusion promoting effect becomes insufficient.

Since the aluminum alloy rolled sheet is usually wound into a coil, it is preferable to carry out machining between a coiler for winding metal to a coil and a final rolling roll stand. In this case, the abrasive grains adhere to the surfaces of the wheels and the sand belts, and are brought into contact with the surface of the metal band for polishing. On the other hand, cutting is performed with a hob cutter. The metal band coil may be once wound and then machined while being rewound.

FIG. 11 is a SEI (Secondary Electron Image) image of a surface obtained by cutting the surface of the Al—Sn—Si based slide bearing alloy rolled plate on which the Fe phase is formed in the vertical direction of the drawing. On the surface of the aluminum matrix, linear cutting marks run vertically. On the other hand, in the irregularly shaped Fe phase, cutting marks are intermittently connected to the surrounding aluminum matrix, and the white and black patterns are mixed with spots. The following can be seen from these linear cutting marks and mottled Fe phase.
(A) The soft aluminum matrix is scraped off linearly by a tool.
(B) The hard Fe phase is divided into small fragments and destroyed.
(C) The entire Fe phase is not scraped off by the tool, and there is a remaining portion.
(D) In the Al-Sn-based or Al-Sn-Si-based aluminum alloy, the surface roughness (JIS (Rz)) after cutting decreases as the amount of Fe increases. This phenomenon is considered to be related to the stabilization of the cutting because aluminum which is a component cutting edge of the cutting tool is scraped off by Fe in the aluminum alloy simultaneously with the breakage of the above (b).

Generally, the pressure welding of the aluminum alloy rolled sheet and the steel back metal is performed at a rolling reduction of 30 to 90%. Thereafter, annealing is performed at 250 to 500 ° C., preferably 300 to 480 ° C.

The distribution and control method of the Fe phase in the aluminum alloy are as described in the first embodiment.

In the Al-Sn-based or An-Sn-Si-based alloy to which the method of the present invention is applied, when the content of Fe is less than 0.2% by mass, sufficient area of the Fe phase is small. No landfill effect can be obtained. On the other hand, when the content of Fe exceeds 1.5% by mass, cold rolling of the rolled sheet becomes difficult.

When molten aluminum alloy having the above composition is poured into a continuous casting mold to form a continuous cast sheet with a thickness of 3 to 20 mm, the temperature of the cast sheet solidified from the molten metal temperature in the mold is 850 to 300 ° C The Fe phase can be formed by cooling at a rate of 2000 to 5000.degree. C./min. In addition, by slowing the cooling rate, it is possible to increase the uptake amount of Al and the additive element.

An intermediate layer made of an aluminum alloy or pure aluminum may be provided between the aluminum alloy rolled sheet and the back metal. For example, when pure aluminum is used as the intermediate layer, the adhesion between the rolled plate and the intermediate layer is diffusion bonding and brazing of Sn, and the connection between the intermediate layer and the back metal is also diffusion bonding. In the brazing of Al-Sn, the recesses formed in the rolled plate can bury molten Sn. When Sn is contained, a recess may be formed on at least the surface on the back metal side of the intermediate layer to bury the Sn of the intermediate layer in order to avoid the decrease in the adhesion between the intermediate layer and the back metal.

FIG. 12 is a schematic view showing the bonding surface of the aluminum alloy rolled plate 28 and the back metal 30. As shown in FIG. Here, a state of being annealed after pressure contact is shown. In addition to the phases shown in FIGS. 4 to 6, the Sn phase 25, the recess 21b and the Sn stream 16 are shown. The concave portion 21 b (black portion) is a portion of the Fe phase 21 scraped off by machining. As described above, since the Fe phase is broken into small fragments, some of them are left, but for convenience of drawing, they are illustrated in black as if the whole was removed. The Sn stream 16 is obtained by drawing a Sn phase ejected from the matrix through a minute gap between the aluminum alloy rolled plate 28 and the back metal 30.

FIG. 13 is a schematic view for explaining the burying of molten Sn. Sn particles 25P are spouted by perspiration. The depth of the recess 21b is, for example, 5 to 30 μm, and the diameter (D) is 1 to 50 μm. As shown in FIG. 4, the Fe phase is present in large numbers on the surface of the alloy layer because the spacing is from sub-μm to several μm. The shortest distance D _Sn between the recess 21 b and the portion where the spout of Sn occurs is also from sub μm to several μm. Therefore, Sn flowing from the spouting point is buried in the recess 21 b with high probability. The spread of Sn can be suppressed according to the filling rate. In addition, as the filling rate increases, the proportion of Al—Fe diffusion bonding in bimetal bonding increases.

The Sn particles 25P may be buried by the recess 28b (FIG. 10) without using the Fe phase. Since a large number of recesses 28 b are formed all over the aluminum alloy rolled plate, Sn particles 25 P can be buried. In the case of shot blasting, mainly a soft aluminum matrix is depressed to form a recess, and in the case of a laser, a recess is formed by evaporation of the substance regardless of the structure and composition of aluminum, but the effect of burying is Is almost the same.

2-2. Experimental Example 2-2-1. Embodiment 2A
An aluminum alloy melt having a composition of Al-6% by mass Sn-3% by mass Si-1% by mass Fe was continuously cast to obtain a continuously cast sheet having a thickness of 15 mm. In addition, in Experimental example 16 (Example), the cooling rate control after casting was performed, and in Experimental example 17 (comparative example), control of cooling in the above-mentioned temperature range was not performed, but cooling and slow cooling were performed. The continuous cast sheet of these experimental examples was cold-rolled to 1.5 mm, and one side of the rolled sheet was cut with a tool to a roughness of 2.5 μm JIS (Ra). Thereafter, the rolled sheet was cut into a length that can be rolled by a laboratory rolling mill, and the cut surface was superimposed on a steel back metal (SPCC, 3 mm thick) and pressed by rolling. The obtained bimetallic specimen was cut into 100 mm and annealed at 360 ° C.

After that, a bending test was performed in which a bimetal-like test material was bent around a round bar with a diameter of 5 mm with the steel back side as the inner side. The bimetallic test material of Experimental Example 16 (Example) was capable of bending up to 180 °, but the bimetallic test material of Experimental Example 17 (Comparative Example) broke at 120 °.

2-2-2. Embodiment 2B
About the aluminum alloy rolling plate used by Experimental example 17, the shot blasting was performed on the conditions of 50 m / sec in projection speed of the SiC projection material with an average particle diameter of 50 micrometers. Using this, a bimetallic test material was produced, and this was taken as Experimental Example 18. When a bending test was conducted on Experimental Example 18, the same results as in Experimental Example 16 were obtained.

According to this embodiment, a bimetallic slide bearing having high strength can be obtained. This bearing is used, for example, in a car. By using this bearing, the reliability is improved, and furthermore, quality control and inspection in a bearing manufacturing plant can be simplified.

3. Third Embodiment 3-1. Overview The following is a summary of the conventional findings on aluminum alloy slide bearings with overlay layers.

(1) Surface treatment of aluminum alloy In Patent Document 5, the surface of the aluminum alloy is subjected to treatments such as alkaline etching, acid pickling and zinc phosphate conversion treatment or baking of the overlay layer without surface treatment. There is. In order to improve the seizure resistance and the fatigue resistance, it is better to apply a surface treatment, but there is a problem that the surface treatment increases the cost.

(2) conformability of familiar and abrasion overlay layer of the overlay layer solid lubricant is ensured particularly in MoS _2. That is, the low friction of the sliding surface and the familiarity are realized by cleavage of the MoS ₂ . In the wear test example of Patent Document 5, the adhesion of the overlay layer is enhanced due to the surface treatment of the underlying aluminum alloy, and wear occurs as a phenomenon in which the thickness of the overlay layer decreases. On the other hand, in Non-Patent Document 4, as the content of MoS ₂ increases, the overlay layer wears away, and the area ratio to which the underlying aluminum alloy is exposed increases. The phenomenon in which the overlay layer is partially worn away to expose the underlying aluminum alloy is also known in metal-based overlay layers such as lead electroplating. In addition, a metal-based overlay layer having good conformability tends to have a large amount of wear, and such a tendency is the same in the overlay layer. The characteristics of the conformability and wear of the overlay layer are that, originally, conformability is realized only by the cleavage wear of the solid lubricant, and it is ideal that only the solid lubricant wears, but the resin that retains the solid lubricant The point is that it also wears out. That is, although polyamide imide resin etc. are excellent in abrasion resistance, abrasion occurs nevertheless.

(3) Fatigue resistance The overlay layer improves the fatigue resistance of the underlying aluminum alloy (Non-patent Document 3, Section 4.3 and Non-patent Document 2, Section 3.1 (2)). That is, the aluminum alloy with the overlay layer is less susceptible to cracking of the alloy itself (lining) than the aluminum alloy without the overlay layer.

(4) Aluminum Alloy for Slide Bearing The overlay layer is considered to be effective for an aluminum alloy of a wide range of compositions shown in Patent Document 5. Of course, the properties of the aluminum alloy are affected by its composition, but the effects of the overlay layer such as seizure resistance and fatigue resistance improvement do not become better or worse with the specific aluminum alloy composition.

(5) Binder resin Although polyamide imide resin is the most excellent in performance, other resins can be used according to application requirements including engine metal.

The present inventors investigated the bearing performance of a polyamideimide resin to which a coupling agent was added in order to enhance the adhesion between the resin and the aluminum alloy. As a result, a certain degree of adhesion improvement effect was recognized. On the other hand, without the addition of the coupling agent and the aluminum alloy surface treatment, the overlay layer is easily worn away during the bearing performance test.

The present embodiment provides a technique for improving the adhesion between an Al—Sn—Si alloy and a resin.

The slide bearing according to one embodiment has a back metal, a lining layer formed on the back metal, and an overlay layer formed on the lining layer.

The lining layer is formed of an aluminum alloy (specifically, an Al-Sn-Si based alloy). The lining layer contains 1 to 20% by mass of Sn, 0.5 to 12% by mass of Si, and more than 0.20% by mass and 2.0% by mass or less of Fe, with the balance being Al and unavoidable impurities It is.

The additive elements, additional elements, and unavoidable impurities of the aluminum alloy are as described in the first embodiment.

Iron is less oxidizable than aluminum and has high surface activity with the resin. Therefore, the adhesion of the resin to the aluminum alloy can be enhanced by adding a large amount of Fe (for example, an amount exceeding 0.20% by mass) to the conventional impurity level to the Al-Sn-Si alloy. When Fe is dissolved in the Al matrix, its inherent properties do not appear. However, Fe hardly dissolves in Al. Fe is present as fine particles in the Al matrix to enhance the activity with the resin.

Also, if the overlay layer is partially worn away, the mating shaft and the lining layer will be in direct contact. In the case where the countershaft is steel, if the amount of Fe in the lining layer is too large, the possibility of sliding of the same material as the countershaft is increased. Also, unlike Sn and Si, Fe does not improve bearing characteristics. From the above viewpoint, the content of Fe is preferably 2.0% by mass or less.

The overlay layer comprises a solid lubricant and a binder resin. The solid lubricant contains at least one of MoS ₂ , PTFE, graphite, WS ₂ , h-BN, and Sb ₂ O ₃ . The binder resin contains at least one of polyamideimide resin, polyimide resin, phenol resin, polyacetal resin, polyetheretherketone resin, polyphenylene sulfide resin, and epoxy resin.

The overlay layer is conventionally known, and as the resin, at least one of polyamideimide resin, polyimide resin, phenol resin, polyacetal resin, polyetheretherketone resin, polyphenylene sulfide resin and epoxy resin can be used. . Among these, polyamide imide, particularly aromatic polyamide imide, is preferable for the overlay layer.

As the solid lubricant, at least one of MoS ₂ , PTFE, graphite, WS ₂ , h-BN and Sb ₂ O ₃ can be used. Among these, MoS ₂ is most preferable. The content of solid lubricant in the overlay layer is 30 to 70% by volume. The thickness of the overlay layer is, for example, 1 to 50 μm.

The overlay layer may include hard particles in addition to the solid lubricant. The hard particles are at least one selected from SiC, Al ₂ O ₃ , TiN, AIN, CrO ₂ , Si ₃ N ₄ , ZrO ₂ , Fe ₃ P, Fe ₂ O ₃ and FeO. The content of hard substance in the overlay layer is preferably 0.1 to 5% by mass, and the average particle size of the solid lubricant is preferably 2 μm. It is preferable that the film thickness of the overlay layer which has the said composition is 10 micrometers.

According to this embodiment, bearing characteristics can be improved as follows.
(1) Conformability and seizure resistance The binder resin of the overlay layer adheres to the lining and becomes difficult to peel off. Therefore, the conformability by the solid lubricant is exhibited sufficiently and quickly. Therefore, fluid lubrication is realized quickly and seizure resistance is improved.
(2) Wear resistance Abrasion due to peeling of the overlay layer is less likely to occur. Also, even if peeling occurs, the overlay layer does not peel off as large pieces of several mm 2 in area. For this reason, a large peeling piece does not intrude into the sliding surface to cause seizing.
(3) Fatigue resistance Although Fe does not directly improve the fatigue resistance of the Al-Sn-Si alloy, stress concentration on the aluminum alloy exposed by the peeling of the overlay layer is avoided to cause fatigue.

3-2. Experimental Example 3-2-1. Adhesion The present inventors conducted the following test on the adhesion (adhesiveness) of the resin and the metal plate.
(1) Test material (a) A plate obtained by degreasing the surface of a rolled aluminium alloy plate manufactured by a usual method.
(B) A plate obtained by degreasing the surface of a low carbon steel plate used for the backing metal of a conventional bimetal slide bearing.
(2) Resin A polyamideimide resin was applied to each of the test materials 1 (a) and (b) and baked at 180 ° C. to form a resin coating film having a thickness of about 6 μm.
(3) Test method The resin coating film was scratched with a cutter knife and a grid pattern was attached.
(4) Evaluation and Results Minute peeling occurred on both sides of the linear wedge of the test material 1 (a), and it was found from this result that the adhesion of resin is lower than that of iron.

3-2-2. Bearing Performance Tables 6 and 7 show the compositions and bearing performances of Experimental Examples 19-30. An aluminum alloy having these compositions was continuously cast into a 15 mm thick plate and cold rolled into a thin plate. After cold rolling, the aluminum alloy was crimped to a backing metal (SPCC steel plate) to form a bimetal. These bimetallic materials were processed into bearings.

Polyamideimide resin (manufactured by Hitachi Chemical Co., Ltd.) and MoS ₂ powder were prepared as raw materials for the overlay layer. These raw materials were blended so that MoS ₂ was 40% by volume, and the remainder was a polyamideimide resin. The raw material was applied to a lining layer (degreased but not subjected to any surface treatment such as pickling) and then baked at 180 ° C. Thus, an overlay layer of about 6 μm in thickness was deposited.

The sliding characteristics of the aluminum alloy rolled sheet with overlay layer were measured by the following method.

The results of the test are shown in Table 7.

From Table 7, in the experimental examples 19 to 26 (examples) in which Fe is added by 0.3 mass% or more, the fatigue resistance and the fatigue resistance are compared with the experimental examples 27 to 29 (comparative examples) in which the addition amount of Fe is small. The burnability is good. However, experimental example 30 (comparative example) in which the content of Fe is 2.5% by mass is inferior in fatigue resistance and seizure resistance to experimental examples 19 to 26.

Claims

1 to 20 mass% of Sn,
0.5 to 12% by mass of Si,
0.05 to 1.5% by mass of Fe,
Including Al and
Si particles dispersed in an Al matrix,
An aluminum alloy having an Fe phase dispersed in an Al matrix.
The aluminum alloy according to claim 1, containing 0.3% by mass or more of Fe.
The aluminum alloy according to claim 1 or 2, wherein Al is taken from the Al matrix in the Fe phase, and the concentration of Al is highest at the interface between the Fe phase and the Al matrix and decreases toward the inside of the Fe phase.
The aluminum alloy according to any one of claims 1 to 3, containing at least one of 0.5 mass% or less of Cr and 3 mass% or less of Cu as additive elements.
The aluminum alloy according to claim 4, wherein the additive element is taken from the Al matrix in the Fe phase, and the concentration of the additive element is highest at the interface between the Fe phase and the Al matrix and decreases toward the inside of the Fe phase.
8 mass% or less in total of at least one of Mg, Ag, and Zn,
The total content of at least one of Zr, Mn, V, Sc, Li, and Ni is 0.5% by mass or less in total, and 0.5% by mass or less in total of Ti and B as unavoidable impurities The aluminum alloy according to any one of the above.
The aluminum alloy according to any one of claims 1 to 6, containing 5% by mass or more of Sn.
The aluminum alloy according to any one of claims 1 to 7, wherein five or more Si particles having a major axis dimension of 5 to 40 μm are present per 3.56 × 10 -2 mm 2 cross section.
The equivalent circle diameter of the Si particles is 2 to 15 μm,
The aluminum alloy according to claim 8, wherein the number ratio of Si particles having a circle equivalent diameter of 4 μm or more is 20% or more.
A lining layer formed of the aluminum alloy according to any one of claims 1 to 9,
A slide bearing having a back metal formed of an Fe-based material.
The slide bearing according to claim 10, wherein a surface of the lining layer in contact with the other shaft is cut.
A lining layer formed of the aluminum alloy according to any one of claims 1 to 9, or an Al-Sn based alloy containing 1 to 20% by mass of Sn.
And a back metal formed of Fe-based material,
An Al—Fe diffusion layer and a soldered surface of Sn are formed at the interface between the lining layer and the back metal,
The lining layer has a plurality of recesses formed in a dispersed manner in the joint surface with the back metal,
A slide bearing in which a part of Sn present at the interface is buried in the recess.
The lining layer is
0.2 to 1.5% by mass of Fe,
With dispersed Fe phase,
The plain bearing according to claim 12, wherein the recess is formed by mechanically scraping the surface of the lining layer.
The slide bearing according to claim 12, wherein the recess is formed by shot blasting.
The slide bearing according to claim 12, wherein the recess is formed by laser processing.
Al-Sn alloy containing 1 to 20% by mass of Sn and 0.2 to 1.5% by mass of Fe or 5 to 20% by mass of Sn, 0.5 to 12% by mass of Si, and 0.2 to 1 .5 mechanically roughening the surface of a rolled sheet of an Al-Sn-Si alloy containing 5% by mass of Fe to a roughness of 1 to 5 μm JIS (Ra) and roughening the surface;
After the roughening, pressing the rolled plate and the Fe-based backing metal by rolling;
After the rolling, annealing at 250 to 500 ° C.
Lining layer,
An overlay layer formed on the lining layer;
The lining layer is
1 to 20 mass% of Sn,
0.5 to 12% by mass of Si,
More than 0.20% by mass and 2.0% by mass or less of Fe,
Including Al and
The overlay layer is
A solid lubricant comprising at least one of MoS 2 , PTFE, graphite, WS 2 , h-BN, and Sb 2 O 3 ;
A slide bearing comprising a polyamide imide resin, a polyimide resin, a phenol resin, a polyacetal resin, a polyether ether ketone resin, a polyphenylene sulfide resin, and a binder resin containing at least one of epoxy resins.
The slide bearing according to claim 17, wherein a content of the solid lubricant in the overlay layer is 30 to 70% by volume.
The overlay layer is made of SiC, Al 2 O 3 , TiN, AIN, CrO 2 , Si 3 N 4 ,
Sliding bearing according to ZrO 2, Fe 3 P, Fe 2 O 3, and claim 17 or 18 further comprising a hard material including at least one of FeO.
The slide bearing according to claim 19, wherein a content of the hard material in the overlay layer is 0.1 to 5% by mass.
The plain bearing according to any one of claims 17 to 20, wherein the lining layer is formed by cold rolling a continuous cast plate.
The lining layer further contains at least one of (a) to (d) (a) at least one of 0.5% by mass or less of Cr and 3% by mass or less of Cu,
(B) 8 mass% or less in total of at least one of Mg, Ag, and Zn,
(C) at least one or more of Zr, Mn, V, Sc, Li, and Ni in a total amount of at most 0.5 mass%,
(D) 0.5 mass% or less in total of at least one of Ti and B as unavoidable impurities
A plain bearing according to any one of claims 17 to 21.
The slide bearing according to any one of claims 17 to 22, further comprising a back metal formed of an Fe-based alloy and pressed against the lining layer.
The slide bearing according to any one of claims 17 to 23, wherein a surface of the lining layer in contact with the opposite shaft is cut.