JPH06313479A - Sliding surface constituting body - Google Patents

Abstract

PURPOSE:To provide a sliding surface constituting body for improving a seizing resistance performance and abrasion resistance performance. CONSTITUTION:A sliding surface constituting body 4 is constituted with the aggregate of Fe crystal having a body-centered cubic structure. The aggregate includes {222} orientation Fe crystal 61 which has oriented a {222} surface to a sliding surface 4a side by means of Miller indices and {211} orientation Fe crystal 62 which has oriented the {211} surface to the sliding surface 4a side by means of the Miller indices. The existing rate S of the {222} orientation Fe crystal 61 is set to relation of S>=20%, and the existing rate S of the {211] orientation Fe crystal 62 is set to relation of 20%<=S<=60%. The {222} orientation Fe crystal 61 is formed in a large triangular pyramid shape in the sliding surface 4a, the hardness thereof is formed at a low level, and it contributes to improvement of initial concordant property. The {211} orientation Fe crystal 62 is formed in a small angular pyramid shape in the sliding surface 4a, and an oil reservoir is formed, and also the {211} orientation Fe crystal 62 contributes to improvement of abrasion resistance performance.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sliding surface structure which constitutes a sliding surface with a mating member.

[0002]

2. Description of the Related Art Conventionally, as a sliding surface structure of this kind, for example, in a piston for an internal combustion engine, Fe provided on the outer peripheral surfaces of a land portion and a skirt portion of an Al alloy base material in order to improve wear resistance. Plating layers are known.

[0003]

However, under the present circumstances where the internal combustion engine tends to have high speed and high output, the conventional sliding surface structure has a difficulty in wear resistance and oil retaining property. That is, there is a problem that the seizure resistance is poor because the oil retaining property is not sufficient and the initial conformability is poor.

In view of the above, the present invention has a relatively high hardness, a sufficient oil retaining property and a good initial conformability by specifying a crystal structure, thereby improving wear resistance and seizure resistance. It is an object of the present invention to provide the above-mentioned sliding surface structure capable of

[0005]

A sliding surface structure according to the present invention is composed of an assembly of metal crystals having a body-centered cubic structure, and the assembly slides on a (hhh) plane at a Miller index. The presence of the (hhh) oriented metal crystal and the (2hhh) oriented metal crystal with the (2hhh) plane oriented toward the sliding surface side by the mirror index, wherein the (hhh) oriented metal crystal is present. The ratio S is S ≧ 20%, and the existence ratio S of the (2hhh) oriented metal crystal is 20% ≦ S ≦ 60%.

[0006]

The (hhh) oriented metal crystal grows in a columnar shape, and has a relatively large pyramid shape or truncated pyramid shape on the sliding surface, and its hardness is relatively low.

On the other hand, the (2hhh) oriented metal crystal has a small pyramid shape or a small cube shape on the sliding surface, and they have a very complicated appearance by digging into each other. Moreover, since the (2hhh) plane of the (2hhh) oriented metal crystal is a secondary slip plane, the crystal has relatively high hardness and high strength.

Therefore, if the abundance S of the (hhh) and (2hhh) oriented metal crystals is set as described above, in the lubrication state, in the valley between the (hhh) oriented metal crystals,
Since the oil pool is formed by the (2hhh) oriented metal crystals, the oil retaining property of the sliding surface structure becomes good. Also (h
hh) The initial conformability of the sliding surface structure is also good due to preferential wear on the tip side of the oriented metal crystal. This improves the seizure resistance of the sliding surface structure.

After the wear of the tip side of the (hhh) oriented metal crystal has progressed, the (hhh) and (2hhh) oriented metal crystals carry a sliding load. Since the progress of wear is suppressed by the hardness and strength of the (2hhh) oriented metal crystal, the wear resistance of the sliding surface structure is improved.

Even in the non-lubricated state, the initial conformability improving effect by the (hhh) oriented metal crystal is obtained, and a flat surface is formed due to the wear of the tip side of the (hhh) oriented metal crystal. , (Hhh) oriented metal crystals provide the lubrication ability due to the softness of the (hhh) oriented metal crystals, and (hhh) oriented metal crystals play a role in seizure resistance, while (2hhh) oriented metal crystals provide wear resistance. Therefore, good sliding characteristics can be obtained.

In the lubricated and unlubricated state, (hh
h) When the abundance ratio S of oriented metal crystals is S <20%, the initial conformability of the sliding surface structure deteriorates. On the other hand, (2hhh)
When the abundance ratio S of oriented metal crystals is S> 60%, the hardness of the sliding surface construct becomes too high, so that the initial conformability similarly deteriorates. Abrasion resistance decreases.

[0012]

1 and 2, a piston 1 for an internal combustion engine is shown.
Has a base material 2 made of Al alloy, and the land portion 3 _{1 of the} base material 2
And the skirt portion 3 ₂ outer circumferential surface, a layered slide surface construction 4 is formed by plating.

As shown in FIG. 3, the sliding surface structure 4 is composed of an aggregate of metal crystals having a body-centered cubic structure (bcc structure). The aggregate has a (hhh) surface directed toward the sliding surface 4a side with the inner wall 5 of the cylinder bore (hhh) with a mirror index.
It includes an oriented metal crystal and a (2hhh) oriented metal crystal with the (2hhh) plane facing the sliding surface 4a side by the Miller index, and the existence rate S of the (hhh) oriented metal crystal is S ≧ 20%.
In addition, the abundance S of (2hhh) oriented metal crystals is 20.
% ≦ S ≦ 60%, respectively.

The (hhh) oriented metal crystal 6 ₁ grows in a columnar shape, and has a relatively large pyramid shape or a truncated pyramid shape on the sliding surface 4a as shown in FIG. Hardness is relatively low.

On the other hand, (2hhh) oriented metal crystal 6
₂ has a small pyramid shape or a small cube shape on the sliding surface 4a, and has a very complicated appearance in which they bite into each other. Moreover, since the (2hhh) plane of the (2hhh) oriented metal crystal 6 ₂ is a secondary slip surface, the crystal 6 ₂ has relatively high hardness and high strength.

Therefore, if the abundance ratio S of the (hhh) and (2hhh) oriented metal crystals is set as described above, in the lubrication state, (2hhh) in the valley between the (hhh) oriented metal crystals 6 _1. Since the oil sump is formed by the oriented metal crystals 6 ₂ , the oil retaining property of the sliding surface structure 4 is improved. In addition, the preferential wear of the tip end side of the (hh) oriented metal crystal 6 ₁ also provides good initial conformability of the sliding surface structure 4. This improves the seizure resistance of the sliding surface structure 4.

(Hhh) After the wear of the tip side of the oriented metal crystal 6 ₁ progresses, (hhh) and (2hhh)
Although the oriented metal crystals 6 ₁ and 6 ₂ bear the sliding load, the progress of wear is suppressed by the oil sump effect and the hardness and strength of the (2hhh) oriented metal crystals 6 _2. Therefore, the wear resistance of the sliding surface structure 4 is improved. Even in non-lubrication state, initial conformability improving effect is obtained, also (hhh) flat surface to it with the oriented metal crystals 6 ₁ of the tip side wear is formed by (hhh) oriented metal crystals 6 ₁ And (hhh) the lubricity resulting from the softness of the oriented metal crystal 6 ₁ is obtained, and seizure resistance is
h) The oriented metal crystal 6 ₁ bears the wear resistance while the (2)
hhh) Since the oriented metal crystal 6 ₂ plays a role, good sliding characteristics can be obtained.

As shown in FIG. 5, the inclination of the (hhh) plane with respect to the virtual surface 7 along the sliding surface 4a appears as the inclination of a triangular pyramid, so that the initial conformability of the sliding surface structure 4 is affected. give. Therefore, the inclination angle θ formed by the (hhh) plane with respect to the virtual plane 7 is set to 0 ° ≦ θ ≦ 15 °. This inclination angle θ is also 0 ° ≦ θ ≦ 15 for the (2hhh) plane.
°. In this case, the inclination directions of the (hhh) plane and the (2hhh) plane are not limited. Tilt angle θ is θ> 15
When the angle becomes °, the oil retaining property and the initial conformability of the sliding surface structure 4 deteriorate.

F is a metal crystal having a bcc structure.
Examples thereof include crystals of e, Cr, Mo, W, Ta, Zr, Nb, V, etc., or alloys thereof.

In the plating treatment for forming the sliding surface structure 4 according to the present invention, the basic conditions for performing the electric Fe plating treatment are as shown in Tables 1 and 2.

[0021]

[Table 1]

As the organic additive, urea, saccharin, etc. are used.

[0023]

[Table 2]

In the electric Fe plating treatment carried out under the above-mentioned conditions, the crystallization and the amount of the (hhh) and (2hhh) oriented Fe crystals were determined by the cathode current density, the plating bath pH, the blending amount of the organic additive and the like. Control.

As the plating treatment, in addition to the electroplating treatment, vacuum plating treatment such as vapor phase plating method (PVD method,
CVD method), sputtering method, ion plating, etc. can be mentioned. The conditions for performing W and Mo plating by the sputtering method are, for example, Ar pressure of 0.8 Pa and Ar.
Acceleration power: DC 1 kW, base material temperature 100 ° C. C
The conditions for performing W plating by the VD method are, for example, raw material WF ₆ , gas flow rate 10 cc / min, chamber pressure.
It is 100 Pa and the base material temperature is 500 ° C.

A specific example will be described below.

The outer peripheral surface of the land portion 3 ₁ and the skirt portion 3 _{2 of the} Al alloy base material 2 is subjected to electric Fe plating to form a sliding surface structure 4 composed of an aggregate of Fe crystals.
To form a plurality of internal combustion engine pistons 1.

Tables 3 and 4 show Examples 1 to 1 of the sliding surface structure 4.
The electric Fe plating processing conditions in No. 6 are shown.

[0029]

[Table 3]

[0030]

[Table 4]

Tables 5 and 6 show the crystal morphology of the sliding surface 4a, the grain size of Fe crystals, the abundance S of each oriented Fe crystal and the hardness in Examples 1 to 16, respectively.

[0032]

[Table 5]

[0033]

[Table 6]

The abundance S is the X-ray diffraction pattern (X
The line irradiation direction is obtained by the following method based on the direction perpendicular to the sliding surface 4a). As an example,
Explaining Example 1, FIG. 6 is an X-ray diffraction diagram of Example 1, and the abundance S of each oriented Fe crystal was obtained from the following equation. Note that, for example, a {110} oriented Fe crystal is {1
It means an oriented Fe crystal with the 10} plane facing the sliding surface 4a. {110} oriented Fe crystal: S ₁₁₀ = {(I ₁₁₀ / IA
₁₁₀ ) / T} × 100, {200} oriented Fe crystal: S ₂₀₀ = {(I ₂₀₀ / IA
₂₀₀ ) / T} × 100, {211} oriented Fe crystal: S ₂₁₁ = {(I ₂₁₁ / IA)
₂₁₁ ) / T} × 100, {310} oriented Fe crystal: S ₃₁₀ = {(I ₃₁₀ / IA
₃₁₀ ) / T} × 100, {222} oriented Fe crystal: S ₂₂₂ = {(I ₂₂₂ / IA)
₂₂₂ ) / T} × 100 where I ₁₁₀ , I ₂₀₀ , I ₂₁₁ , I ₃₁₀ , and I ₂₂₂ are the measured values (cps) of the X-ray reflection intensity of each crystal plane, and IA ₁₁₀ , IA ₂₀₀ , and IA. ₂₁₁ , IA ₃₁₀ , and IA ₂₂₂ are the X-ray reflection intensity ratios of each crystal plane in the ASTM card,
IA ₁₁₀ = 100, IA ₂₀₀ = 20, IA ₂₁₁ = 30,
IA ₃₁₀ = 12 and IA ₂₂₂ = 6. Furthermore, T is T
= (I ₁₁₀ / IA ₁₁₀ ) + (I ₂₀₀ / IA ₂₀₀ ) + (I
₂₁₁ / IA ₂₁₁ ) + (I ₃₁₀ / IA ₃₁₀ ) + (I ₂₂₂ /
IA ₂₂₂ ).

FIG. 7 is a micrograph showing the crystal structure of the sliding surface 4a in Example 1. FIG.
The same figure (b) is 5000 times. In FIG. 7, a large number of relatively large triangular pyramid-shaped (hhh) oriented Fe crystals and a large number of small pyramid-shaped (2hhh) oriented Fe crystals are observed. (Hh) Oriented Fe crystal is (hh)
h) plane, and thus {222} plane, is a {222} oriented Fe crystal having the sliding surface 4a side, and the abundance ratio S of the {222} oriented Fe crystal is as shown in Table 5 and FIG. To
S = 40.6%. The (2hhh) oriented Fe crystal has the (2hhh) plane, and therefore the {211} plane is the sliding surface 4a.
A {211} oriented Fe crystal facing the
The abundance ratio S of the 11} oriented Fe crystals is S = 30% as shown in Table 5 and FIG. An oil sump is formed between {222} oriented Fe crystals, and an oil sump is also formed by {211} oriented Fe crystals which are crystallized in a highly intricate state in their valleys.

Next, with respect to Examples 1 to 16, a seizure test by a chip-on-disk system was conducted in a lubricated state,
When the seizure load was determined, the results shown in Table 7 were obtained. The test conditions are as follows. Disc material Al-1
0 wt% Si alloy, disk rotation speed 15m / sec
, Lubrication rate 0.3 ml / min, sliding surface area of chip made of sliding surface structure 1 cm ² .

[0037]

[Table 7]

Further, Examples 1, 15 and 16 were subjected to a wear test by a chip-on-disk method under lubrication to determine the wear amounts thereof, and the results shown in Table 8 were obtained. The test conditions are as follows. Disk material Al-10
Weight% Si alloy, disk rotation speed 5 m / sec, oil supply amount 0.3 ml / min, load 100 N, sliding distance 10
km, sliding surface area of chip made from sliding surface structure 1 cm ² . The amount of wear is reduced per 1 cm ² of chip area (m
g).

[0039]

[Table 8]

FIG. 8 is a graph showing the relationship between Examples 1, 15 and 16 in Table 7 and the seizure-generating load, and FIG.
Is a graph showing the relationship between Examples 1, 15 and 16 in Table 8 and the wear amount. Example 1 from Tables 5 to 8 and FIGS. 8 and 9.
It can be seen that the seizure load is high and the amount of wear is small. This is because the abundance S of {222} oriented Fe crystals is S
≧ 20%, and the existence ratio S of the {211} oriented Fe crystals is 20% ≦ S ≦ 60%. Example 1
5, the abundance ratio S of {211} oriented Fe crystals was S <20.
%, The hardness is low and the seizure resistance is good, but the wear resistance is inferior to that of Example 1. Example 16 is {22
The abrasion resistance is excellent because the abundance S of the 2} oriented Fe crystals is S <20% and the abundance S of the {211} oriented Fe crystals is S> 60%. However, it has poor seizure resistance.

FIG. 10 shows {211} in Examples 1 to 14.
The relationship between the abundance ratio S of oriented Fe crystals and the seizure generation load is shown. In the figure, points (1) to (14) correspond to Examples 1 to 14, respectively. Line x ₁ is the case where the abundance rate S of {222} oriented Fe crystals is 40% ≦ S ≦ 43%, and line x ₂ is the abundance rate S of {222} oriented Fe crystals is 20% ≦ S ≦ Two
3%, and the line x ₃ is the case where the abundance ratio S of {222} oriented Fe crystals is 10% ≦ S ≦ 15%.

From Table 5, Table 6 and FIG. 10, Examples 1, 2, 5
9, the abundance ratio S of {222} oriented Fe crystals is S ≧
It can be seen that the seizure resistance of the sliding surface structure 4 is improved by setting the existence rate S of the {211} oriented Fe crystals to 20% ≦ S ≦ 60%, respectively.

Next, a wear test by a chip-on-disk method was performed on Examples 6, 8, 9, and 10 without lubrication, and the presence rate S of {211} oriented Fe crystals and Example 6,
When the relationship with the wear amount of 8, 9, 10 was obtained, Table 9,
The results shown in FIG. 11 were obtained. The test conditions are as follows. Disc material: Al-10 wt% Si alloy, disc rotation speed: 0.5 m / sec, load: 100 N, sliding distance: 1 km, sliding surface area of a chip made of sliding surface structure: 1 cm ² . The amount of wear is the amount of loss (mg) per 1 cm ² of chip area.

[0044]

[Table 9]

FIG. 11 is a graph of Table 9, in which points (6), (8) to (10) correspond to Examples 6, 8 to 10, respectively. From Table 5, Table 6, Table 9 and FIG. 11, the existence rate S of {211} oriented Fe crystals was S ≧ 20% and the presence of {222} oriented Fe crystals as in Examples 6, 8 and 9. It can be seen that the wear resistance of the sliding surface structure 4 is improved even under non-lubrication by setting the ratio S to 20% ≦ S ≦ 60%.

The sliding surface structure is applied to a sliding portion such as the following internal combustion engine parts. Piston (ring groove), piston ring, piston pin, connecting rod, crankshaft, bearing metal, oil pump rotor, oil pump rotor housing, camshaft, spring (end surface), spring seat, spring retainer,
Cotta, rocker arm, roller bearing outer case, roller bearing inner case, valve stem, valve face, hydraulic tappet, water pump rotor shaft, pulley, gear, transmission shaft part, clutch plate, washer, bolt (seat surface, screw part).

[0047]

According to the present invention, by specifying the crystal structure as described above, it is possible to provide a sliding surface structure excellent in seizure resistance and wear resistance.

[Brief description of drawings]

FIG. 1 is a side view of a piston.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is a perspective view showing a body-centered cubic structure and its (hhh) plane and (2hhh) plane.

FIG. 4 is a plan view of an essential part showing an example of a sliding surface structure.

FIG. 5 is an explanatory diagram showing an inclination of a (hhh) plane in a body-centered cubic structure.

FIG. 6 is an X-ray diffraction diagram of an example of a sliding surface structure.

FIG. 7 is a micrograph showing a crystal structure of a sliding surface in a sliding surface structure, wherein (a) is 1000 times and (b) is 50 times.
It is 00 times.

FIG. 8 is a graph showing seizure-generating loads of Examples 1, 15, and 16.

FIG. 9 is a graph showing wear amounts of Examples 1, 15, and 16.

FIG. 10 is a graph showing the relationship between the abundance of {211} oriented Fe crystals and the seizure load in Examples 1 to 14.

FIG. 11 is a graph showing the relationship between the abundance of {211} oriented Fe crystals and the amount of wear in Examples 6, 8, 9 and 10.

[Explanation of symbols]

4 Sliding Surface Structure 4a Sliding Surface 6 ₁ (hhh) Oriented Fe Crystal 6 ₂ (2hhh) Oriented Fe Crystal

[Procedure amendment]

[Submission date] November 29, 1993

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be corrected] 0025

[Correction method] Change

[Correction content]

[0025] As the plating process, the outside of the electroplating process, may be mentioned PVD method is an example Ebakisho plating method, CVD method, sputtering method, ion plating or the like. Conditions for performing W and Mo plating by the sputtering method are, for example, Ar pressure of 0.2 to 1 Pa and Ar acceleration power.
The direct current is 1 to 1.5 kW and the base material temperature is 150 to 300 ° C. Conditions for performing W plating by the CVD method are, for example, raw material WF ₆ , gas flow rate 2 to 15 cc / min, chamber internal pressure 50 to 300 Pa, base material temperature 400 to 6
It is 00 ° C.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Name of item to be corrected] 0032

[Correction method] Change

[Correction content]

[0032]

[Table 5]

[Procedure 3]

[Document name to be amended] Statement

[Correction target item name] 0033

[Correction method] Change

[Correction content]

[0033]

[Table 6]

[Procedure amendment 4]

[Document name to be amended] Statement

[Name of item to be corrected] 0037

[Correction method] Change

[Correction content]

[0037]

[Table 7]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Katsumune Tabata 1-4-1 Chuo, Wako-shi, Saitama Stock Research Institute Honda Technical Research Institute

Claims (1)

[Claims] 1. An aggregate of metal crystals having a body-centered cubic structure, which aggregate has a mirror index (hhh) plane toward the sliding surface (hhh) oriented metal crystal and a mirror. Index (2hhh) face toward sliding surface (2hhh)
h) oriented metal crystals, the abundance ratio S of the (hhh) oriented metal crystals is S ≧ 20%, and
hh) The abundance S of oriented metal crystals is 20% ≦ S ≦ 60%
The sliding surface structure characterized by being.