JPS63144042A - Combination sliding member - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a combination sliding member, in particular, one member is made of aluminum alloy (hereinafter abbreviated as "aluminum alloy"),
The present invention relates to a combination sliding member in which the other member is made of polyimide resin.

(Prior Art) In order to reduce the weight of sliding members used in self-splitting cars and the like, aluminum alloys are required to be used as the base material. However, aluminum alloy itself has a drawback of poor wear resistance when used as a sliding member. As a way to completely compensate for this drawback, it is said that an alumite film is formed on the surface by a positive oxidation treatment (see ``Mechanical Design'', Vol. 2).
9, No. 15, pp. 77-86, 1985].

Products on which this alumite film is formed (hereinafter referred to as "anodized materials") have significantly improved wear resistance, even though the base material is an aluminum alloy.

However, if both of a pair of combined sliding members are made of anodized aluminum, the covering materials will slide, resulting in more wear. has less wear.

Therefore, conventional sliding members are made of anodized aluminum alloy, which is made of alumite V, and the next material is used as the body side member, and a steel with excellent wear resistance or heat-treated steel is used as the valve side member. A sliding member is used.

(Problems to be Solved by the Invention) However, when the combined sliding member is used in a piston type, the following problems occur due to temperature changes in lubricating oil.

In other words, because the coefficient of thermal expansion is different between the body side (aluminum alloy alumite layer) and the valve side (ferrous material),
At low temperatures, the clearance of the sliding parts is small, causing cysticity (defective valve sliding), and at high temperatures, the clearance increases, causing oil leakage. Furthermore, when the valve is left to cool after being used at a high temperature, there is a problem in that foreign matter in the lubricating oil circuit remains between the valve and the body, causing stickiness.

As a countermeasure, it is of course best to use materials with the same coefficient of thermal expansion as possible for both the body side and the valve side.For this reason, it is possible to use anodized aluminum alloy for the valve side as well, and it is partially practical. has been made into

Although this combination does not cause problems due to the above-described changes in clearance, etc., there is a problem in that the alumite layers have poor abrasion resistance when sliding against each other as described above. Therefore, as an alternative method, it has been proposed to apply various types of plating to aluminum alloys in order to improve wear resistance. , (1) JP-A-58-146763, (2) JP-A-6O-165389), but no satisfactory effect has been obtained.

The present invention has been made to solve the above problems,
The object is to provide a combination sliding member that is lightweight, has excellent wear resistance and seizure resistance, and does not cause clearance changes due to temperature even when used in a piston type.

(Means for Solving the Problems) In the combined sliding member of the present invention that can achieve the above object, one member is made of an aluminum alloy with an alumite layer formed on the sliding surface, and the other member is made of the aluminum alloy. The polyimide resin has a linear expansion coefficient difference of 3×10/° C. or less.

One of the members, the alumite layer forming member, was prepared using a conventional method.
It is obtained by treating an aluminum alloy capable of forming an alumite layer on the polar side using an electrolytic bath, such as a sulfuric acid bath, a cooler acid bath, or a mixed acid bath thereof. The hardness of this alumite film may be Hv150 or more. Below that, the alumite layer will rapidly wear out.

It is important to select the polyimide resin used as the other member not only to have the specified heat resistance and abrasion resistance, but also to have a coefficient of linear expansion that is ±3 x 104 times the coefficient of linear expansion of the aluminum alloy. ◎Difference in linear expansion coefficient is 3X10, -
For products over 6/℃, piston type is used at high temperature (150℃)
This is because foreign matter in the lubricating oil circuit tends to cause residual cysticity between the body and the valve when it is used as a toilet and left to cool.
This is because at temperatures below 107°C, even if foreign matter remains, it will cause some scratch marks between the body and the valve, but no stick will occur.

The polyamide resin contains graphite and/or polytetrafluoroethylene resin in an amount of 20% by weight or less, and a total of 30% by weight.
It is preferable to mix the following.

The abrasion resistance is improved by mixing them, but no further effect is seen even if the amount exceeds 20%, and if the total exceeds 30% by weight, the strength of the polyimide resin decreases and the abrasion resistance On the contrary, it decreases.

The combined sliding member of the present invention has good wear resistance and seizure resistance, and has very little change in clearance due to temperature, so it is suitable as a piston-type sliding member, especially for the body of an oil passage switching device of an automatic transmission. Suitable as a combination sliding member for valves.

(Example) Examples of the present invention will be described below together with comparative examples, but the present invention is not limited thereby.

Example 1 A cylindrical piece with an outer diameter of 35 rrm, an inner diameter of 30 mm, and a width of 10 strokes was made using aluminum alloy (JIS standard ADC12), and then its outer peripheral surface was anodized using a sulfuric acid bath. As a result, a cylindrical test piece having an oxide film (alumite layer) having a thickness of 10 μm and a hardness of Hv3aa was prepared.

On the other hand, the size of the mating member is 16mm x 16mm x 1
A polyimide resin dice test piece with a diameter of 0 mm was prepared. The polyimide resin used here has a linear expansion coefficient of 20
×10/c. The fabrication process involved compression molding a thermosetting polyimide resin intermediate, which can be called a precondensate, under heating.

The dice test piece made of polyimide resin and the cylindrical test piece made of alumite material were combined and subjected to the wear test described later.

Example 2 When exploding a polyimide resin dice test piece, general-purpose graphite for resin addition was added in 1. A combination test piece was prepared in the same manner as in Example 1 except that -515% by weight was mixed uniformly,
It was subjected to the abrasion test described later.゛Example 3 Example except that a polyimide resin dice test piece was prepared in which 10% by weight of tetrafluoroethylene resin (trade name: Teflon) was mixed in place of 15% by weight of graphite by a conventional method. A combination test piece similar to No. 2 was prepared and subjected to an abrasion test.

Comparative Examples 1 to 3 Dice test pieces made of aluminum wrought material (JIS standard A6063) were anodized to form an alumite layer (thickness 2
Three types of dice test pieces were prepared: a test piece with a hardness of 5 μm and a hardness of Hv 400), and a test piece made of steel (JI8 standard 845C) with a hardness of f (vsso) by quenching. Each of them was combined with the same cylindrical test piece as in the example and subjected to the abrasion test described later.

Table 1 shows the members of the above-mentioned Comparative Examples 1-3 and the above-mentioned Examples 1-30 combination test pieces in an easy-to-understand manner.

Table 1 Wear test Each combination test piece of Examples 1 to 3 and Comparative Examples 1 to 3 was set in a friction and wear tester in sequence, and the outer peripheral surface of the cylindrical test piece was brought into contact with the 16 mm x 16 mm surface of the dice test piece. A wear test was conducted in which the cylindrical test piece was rotated for 30 minutes at a load of 60 to 16 Orpm while supplying lubricating oil (ATF: trade name "Dexron I J") at a temperature of 25 °C to the contact part of the piece. The surface roughness of the test piece and the dice test piece are α8μkLz and 12μR1z, respectively.

The results of this wear test are shown in FIG. In the figure, the upper half represents the wear amount (wear loss '2) of the cylindrical test piece, and the lower half represents the wear amount (wear scar depth μ) of the dice test piece.

Figure 1 shows that the aluminum wrought material without surface treatment (A
It can be seen that the wear of the cylindrical test piece is greater in the case of the combination B of the alumite materials. Combinations of alumite material and polyimide resin of Examples 1 to 3 (D, E, F) t! , it can be seen from the comparison of the wear amount of the cylindrical test piece and the dice test piece that it is not inferior to the combination C of Comparative Example 3 of alumite material and hardened steel. It is also found that the addition of graphite or tetrafluoroethylene resin to the polyimide resin improves the wear resistance.

Examples 4 to 6 Examples 4.5 and 6 were made of the same combination members as those in Table 1, B and F, and each had an outer diameter of 25.4 m.
All the combined cylindrical test pieces having a diameter of 20 mm, an inner diameter of 20 mm, and a length of 10 mm were prepared and subjected to the following seizure test.

Comparative Examples 4 to 6 Comparative Examples 4.5 and 6 were made of the same combination members as A, B, and C in Table 1, respectively, and each had an outer diameter of 25.4 mm.
A combined cylindrical test piece with an inner diameter of 20 mm and a length of 10 mm was prepared and subjected to the following seizure test in the same manner as in Examples 4 to 6.

The cylindrical end surfaces of the cylindrical test pieces of each combination of seizure test Examples 4 to 6 and Comparative Examples 4 to B were brought into contact with each other, lubricating oil (trade name: Castle Motor Oil J5W-30) was supplied, and the rotation speed was 21a.
It was confirmed that the samples in Table 2 had better seizure resistance than those of each comparative example when the pressure cylinder i was set to aarpm and the pressure cylinder i was set to 700)4 from the beginning of 10.

Example 7 and Comparative Examples 7 and 8 FIG. 2 shows the hydraulic switching device 37FI built into the automatic transmission 7.

The valve body 111r, aluminum alloy (JI
Manufactured using S standard ADC10) t- with alumite treatment. In addition, shift valves 2 gold, B and C shown in Table 1
, and D were made of the same material as the 3a class Suikoro test pieces. The hydraulic switching device 3 obtained by combining these valves 2 and the body 1 is actually installed in the transmission of a vehicle, and the valve is operated for 90,000 cycles (1
A durability test was conducted to compare the damage after operation of the OOHR. In addition, the outer diameter of the valve was set to f i Omm, and the clearance between the valve and the body was set to 40 μm.

The results are summarized in Table 3. Comparative Example 8 Alumite material and hardened steel combination c: The one made by ci is 4Q,
After 000 cycles of operation, sticking occurred and the valve stopped working. Furthermore, in Comparative Example 7, which was manufactured using combination B of alumite materials, sticking did not occur, but both the body and the valve had significant wear. In comparison, those manufactured using combination D of alumite material and polyimide resin in Example 7 showed good results as seen from Table 3.

゛ Table 3: Durability test results (effects of the invention) The combined sliding member of the present invention has twice the seizure resistance and twice the wear resistance of conventional sliding members made of a combination of aluminum alloys. It exhibits extremely superior performance, 4 times that of other materials in total. Therefore, it can be used as a piston-type sliding member that is placed under severe sliding conditions.

When used in a piston type, the combined sliding member of the present invention has little clearance change due to thermal expansion and does not cause sticking.

Furthermore, it has better wear resistance and seizure resistance than aluminum alloy and steel combination sliding members, so wood combination sliding members can be used instead, contributing to weight reduction of sliding parts. .

[Brief explanation of the drawing]

Figure 1 is a diagram showing the wear test results of the combined sliding member of the example of the present invention in comparison with that of a comparative example, FIG. In the figure, 1... Valve body 2... Shift valve patent Applicant Toyota Motor Corporation Figure 1

Claims (4)

[Claims] (1) One member is an aluminum alloy with an alumite layer formed on the sliding surface, and the other member is a polyimide resin whose linear expansion coefficient difference from the above aluminum alloy is 3 x 10^-^6/℃ or less A combination sliding member characterized by: (2) Claim 1, characterized in that the polyimide resin that is one of the members contains graphite and/or tetrafluoroethylene resin at 20% by weight or less, and 30% by weight or less in total. combination sliding member. (3) The combination sliding member according to claim 1 or 2, wherein one member is a body and the other member is a piston-type sliding member of a valve. (4) The combined sliding member according to claim 3, wherein the piston-type sliding member is a body and a valve of an oil path switching device of an automatic transmission.