JP2705781B2 - Bearing metal for large engines - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improved bearing metal for a large engine.

[0002]

2. Description of the Related Art The present inventor has already disclosed Japanese Patent Publication Nos. 61-17893 and 61-6138 as prior art relating to the present invention.
No. is disclosed.

[0003]

This prior art is good in non-seizure and storability, but with the recent rapid progress of internal combustion engines, there have been cases where fatigue strength is not always satisfactory. There has been a demand for bearing metals having even better fatigue strength.

[0004] It is an object of the present invention to provide a bearing metal for a large engine which is excellent in fatigue strength while solving the above-mentioned problems and without impairing the non-seizure property. The above prior art required more than 50% of Sn to maintain non-seizure properties. However, if Sn exceeds 50%, desired fatigue strength cannot be obtained. In order to improve the fatigue strength, the product of the present invention
In order to reduce the amount of n and obtain the same non-seizure property as the prior invention,
b was added.

[0005]

Means for Solving the Problems The gist of the present invention is as described in claims (1) to (3). That is, (1) In a bearing metal for a large engine composed of three layers of a steel back metal layer, an Al or Al alloy adhesive layer, and a bearing alloy layer,
The composition of the bearing alloy layer is more than 40% by weight Sn : 50%.
% , Pb: more than 2% and 10% or less , Cu: 0.1%
-1.5% bearing metal for large engines, the balance being substantially Al. (2) In a large engine bearing metal comprising a steel back metal layer, an Al or Al alloy adhesive layer, a bearing alloy layer, and a surface layer made of Pb or Sn or an alloy thereof, the composition of the bearing alloy layer is weight. And Sn : more than 40% and less than 50%
Below , Pb : more than 2% and 10% or less , Cu: 0.1%
1.5% bearing metal for large engines consisting essentially of Al. (3) The composition of the bearing alloy layer according to claim 1 or 2, further comprising Mn, Ni, Si, Ag,
The claim 1 or claim 2, wherein one or more of Mg, Sb, and Zn contains 5% or less by weight in total .
The bearing metal for a large engine according to item 2 . Steel back metal layer thickness is 1
-20 mm, the thickness of the adhesive layer is 0.01-0.15 mm
Preferably, the thickness of the bearing alloy layer is 0.2-3 mm, and the thickness of the surface layer is 1-30 μm.

[0006]

The reasons for limiting the components of each layer in the structure of the bearing metal for a large engine according to the present invention and the effects thereof will be listed below. (1) Steel back metal layer Conventionally known and publicly used steel, for example, carbon steel for general structure specified by JIS is used. (2) Intermediate layer This is to improve the adhesion between the steel back metal and the bearing alloy layer.
Conventionally known pure Al or an Al alloy to which 0.1 to 2% by weight or less of Cu, Si, Mn, Zn, or the like is added as an additional element when the strength is further required can be used. . In addition, when the additive element is added, if it is less than 0.1%, the effect of the addition is not significant, and if it is more than 2%, it becomes brittle and is not suitable for practical use.

(3) Bearing alloy layer (a) Sn : more than 40% but not more than 50% and not more than 40%, both the non-seizure property and the filling property are insufficient, and if it exceeds 50%, the fatigue strength is insufficient. Become. (B) Pb: more than 2% and not more than 10% Pb is alloyed with Sn to improve the lubricating properties and conformability of Sn. If the content is less than 2%, the effect of the addition is insufficient.
If it exceeds 10%, the melting point is too low, which causes a problem in production. (C) Cu: 0.1-1.5% Cu improves the fatigue strength, which is a bearing characteristic, and also improves the adhesive strength with the surface layer. If it is added in excess of 0.5%, the alloy hardness becomes too large, and the initial conformability and fillability deteriorate . In addition, production is difficult because ductility is impaired. (D) One or more of Mn, Ni, Si, Ag, Mg, Sb, and Zn, the total amount of which is 5% or less by weight. The total amount is added for the purpose of improving the mechanical strength of the Al matrix. Exceeds 5%, the initial conformability and the retrievability become poor . Therefore , the upper limit is set to 5%.

(4) Surface layer Provided to improve non-seizure property, burying property, initial conformability, etc., mainly composed of Pb, Sn or an alloy thereof, and Cu, and / or In for improving performance. May be added as an additional element. Further, a thin layer such as nickel plating may be provided between the bearing alloy layer and the surface layer in order to improve the adhesion between the bearing alloy layer and the surface layer. In addition, as a means for coating the surface layer, it is also possible to adhere by PVD or the like other than electroplating.

[0009]

The present invention will be described more specifically with reference to the following examples. Tables 1 and 2 show the chemical components of the bearing alloy layer used for the bearing metal of the present invention and the conventional bearing alloy layer. An alloy plate having the composition shown in Tables 1 and 2 and an Al foil were superimposed on each other, passed through a rolling mill and roll-bonded to form a composite plate having a thickness of 1 mm. The resultant was roll-pressed to obtain a 1.65 mm-thick three-layer composite (bearing alloy layer + Al intermediate adhesive layer + steel back metal layer). The thickness of the bearing alloy layer at this time is 0.42 to 0.43 mm
The thickness of the Al intermediate layer was 0.02 to 0.03 mm, and the thickness of the steel back metal layer was 1.2 mm. The three-layer composite is pressed to obtain a semi-circular bearing metal having a diameter of 53 mm and a length of 17 mm (or a surface layer is formed on the surface of the bearing alloy by electroplating in a known fluoridation bath. Coated to obtain a four-layer composite having a 20 μm thick surface layer), which were used for baking and fatigue tests. Figure 1,
FIG. 2 shows an enlarged sectional view of the three-layer and four-layer bearing metals.
1 is a steel backing metal layer, 2 is an Al adhesive layer, 3 is a bearing alloy layer, and 4 is a surface layer. Table 3 shows the conditions of the fatigue test, and Table 4 shows the conditions of the seizure test. Table 5 shows the results of the fatigue test, and Table 6 shows the results of the seizure test.

[0010]

The present invention has the following excellent effects. (1) From the fatigue test results in Table 5, it can be seen that all bearings of the present invention have improved fatigue strength as compared with conventional bearings.
This is an effect of regulating the amount of Sn to 50% or less. (2) From the seizure test results in Table 6, it can be seen that all the bearings of the present invention have the same or higher non-seizure property as the conventional bearing. This is because Pb is added and alloyed with Sn,
This is because the lubrication characteristics of n have been improved. (3) From the above test results, all bearings of the present invention have improved fatigue strength without impairing seizure performance as compared with conventional bearings. (4) Therefore, the product of the present invention can achieve the initial purpose. That is, the product of the present invention can be applied to a bearing metal for a large engine, which is required to have higher fatigue strength in recent years.

[0011]

[Table 1]

[0012]

[Table 2]

[0013]

[Table 3] Fatigue test conditions

[0014]

[Table 4] Seizure test conditions

[0015]

[Table 5]

[0016]

[Table 6]

[0017]

[Brief description of the drawings]

FIG. 1 is a sectional view of a three-layer bearing metal of the present invention.

FIG. 2 is a sectional view of a four-layer bearing metal of the present invention.

[Description of Signs] 1 steel backing metal layer 2 Al bonding layer 3 bearing alloy layer 4 surface layer

Continuation of front page (72) Inventor Masahiro Nakano 6-13-13 Unumahaba-cho, Kakamigahara-shi, Gifu (56) References JP-A-55-122850 (JP, A) JP-A-56-35744 (JP, A) JP 52-12131 (JP, B2)

Claims (3)

(57) [Claims] 1. In a bearing metal for a large engine comprising a steel backing metal layer, an Al or Al alloy adhesive layer and a bearing alloy layer, the composition of the bearing alloy layer exceeds 40% by weight of Sn.
50% or less , Pb: more than 2% and 10% or less , Cu:
0.1% -1.5%, with the balance being substantially Al, bearing metal for large engines. 2. A steel back metal layer, an Al or Al alloy adhesive layer,
In a bearing metal for a large engine comprising four layers of a bearing alloy layer and a surface layer made of Pb or Sn or an alloy thereof,
The composition of the bearing alloy layer is more than 40% by weight Sn : 50%.
%, Pb: more than 2% and 10% or less , Cu: 0.1%
-1.5%, bearing metal for large engines consisting essentially of Al. 3. The bearing alloy layer according to claim 1 or 2, further comprising Mn, Ni, Si, Ag, Mg, S.
3. The method according to claim 1, wherein one or more of b and Zn contain 5% or less by weight in total.
Large institutions bearing metal.