JPS6264467A - Sliding member made of aluminum alloy - Google Patents

Abstract

PURPOSE:To obtain the sliding member made of A alloy having the adequate scratch hardness and sufficient strength by specifying respectively the alphametic rate of the alumina fiber used for the reinforcing material of the sliding part of the sliding member made of Al alloy and the volume content. CONSTITUTION:The scratch hardness optimum for a high strength sliding member is held on an alumina fiber by making the alphametic rate of the alumina fiber 10.0-50.0% in the Al alloy made sliding member composing the sliding part by the fiber reinforced A alloy with the alumina fiber as the reinforcing material. The wear of the counterpart material is reduced by increasing the size resistance and wear resistance as well as performing the fiber reinforcement of the sliding part in the sliding member sufficiently with 8.0-20.0% volume content of the alumina fiber as well.

Description

[Detailed Description of the Invention] A3 Objective of the Invention (1) Industrial Application Field The present invention provides an aluminum alloy sliding part, particularly a sliding part,
This invention relates to improvements in products made of fiber-reinforced aluminum alloys using alumina fibers as a dispersion material.

(2) Conventional technology Conventionally, in the sliding part of the aluminum alloy sliding member, the gelatinization rate of the alumina fiber, which is the reinforcing fiber, and the volume content of the alumina fiber with respect to the total volume of the sliding part have been determined. No special consideration has been given to the relationship.

(3) Problems to be Solved by the Invention However, since the gelatinization rate of alumina fibers has a significant effect on the strength and hardness of the fibers, it is necessary to set the value appropriately. Furthermore, even if the strength of the alumina fibers is appropriate, if the volume content is inappropriate, not only will the sliding part not be sufficiently reinforced with fibers, but the sliding part and the mating material will wear out. There is a problem that this results in an increase in the amount of carbon dioxide and a decrease in seizure resistance and thermal conductivity.

An object of the present invention is to provide the aluminum alloy sliding member that can solve the above problems.

B6 Structure of the Invention (1) Means for Solving the Problems The present invention sets the gelatinization rate of the alumina fibers to 10.0 to 50.0%, and increases the ratio of the alumina fibers to the total volume of the sliding part. It is characterized in that the volume content is set at 8.0 to 20.0%.

(2) Effect The gelatinization rate of the alumina fiber is set to 10.0 to 50.
By setting it to 0%, the alumina fiber can be made to have high strength and scratch hardness suitable for use in sliding members. However, when the gelatinization rate is less than 10.0%, the scratch hardness decreases, while when the gelatinization rate exceeds 50.0%, the scratch hardness increases, making it unsuitable for use in sliding members.

Further, when the gelatinization rate exceeds 50.0%, there is also a problem that the alumina fibers become bent.

By setting the volume content of alumina fibers having the above-mentioned pregelatinization rate to 8.0 to 20.0% as described above, the sliding portion of the aluminum alloy sliding member is sufficiently reinforced with fibers, and the sliding portion is It is possible to improve the seizure resistance and wear resistance of the moving parts, and to reduce the amount of wear on the mating material.

However, if the volume content is less than 8.0%, the fiber reinforcing ability of the sliding part will be small, and the wear resistance and seizure resistance will be reduced.

On the other hand, if the volume content exceeds 20.0%, the filling properties of the aluminum alloy matrix will deteriorate, making it impossible to sufficiently strengthen the fibers, and the hardness of the sliding parts will increase, resulting in the amount of wear of the mating material. increases, and the thermal conductivity also decreases.

(3) Embodiment Figures 1 to 3 show an internal combustion interstage cylinder block 1 as a sliding member made of aluminum alloy, and the inner wall 1a of the cylinder pore 2, which is the sliding part, is made of alumina fiber as a dispersion material. Constructed from fiber-reinforced aluminum alloy.

The cylinder block 1 is made of alumina fiber 30.
A cylindrical molded body preheated to 0°C is placed in a mold cavity preheated to 200°C, and an aluminum alloy specified by JIs ADC12 is heated to a hot water temperature of 730 to 740°C1.
It is cast by casting at a filling pressure of 260 kg/cIIt. During the casting of this cylinder block, the aluminum alloy is filled into the molded body and composited, so that a fiber-reinforced aluminum alloy is formed.

An aluminum alloy piston 3 is slid into the cylinder bore 2, and two compression rings 4 and one oil shovel ring 5 are attached to the piston 3.

The alumina fibers used in the present invention include alumina fibers and alumina whiskers.

FIG. 4 shows the relationship between the gelatinization rate, Young's modulus (■), tensile strength II), and Mohs hardness III) of alumina fibers.

When the gelatinization rate of the alumina fibers is in the range of 10.0 to 50.0%, the alumina fibers can have high strength and scratch hardness, that is, Mohs hardness, suitable for use in sliding members. In this case, the gelatinization rate of alumina fiber is 30.0 to 40
．． At 0%, the tensile strength of the alumina fibers decreases little and the scratch hardness is high, so using this type of alumina fiber can provide optimal sliding characteristics.

Figure 5 shows the chip-on-disc sliding motion between fiber-reinforced aluminum alloys with a volume content of alumina fibers set at 12% and various gelatinization rates, and the mating material, spheroidal graphite cast iron (JIS FCD75). Show the test results. Line (IV
) corresponds to the seizure limit characteristic, and the line (V) corresponds to the scratch limit characteristic.

In this case, the alloy corresponds to the constituent material of the inner wall portion 1a of the cylinder bore 2, and the tip is formed of this material. Further, the cast iron corresponds to the constituent material of the compression ring 4, and a disk is formed from this material.

The test method was to rotate a disk at a speed of 9.5 m/s, and press the sliding surface of the chip against the sliding surface of the disk with a predetermined pressing force without lubrication. The relationship between the gelatinization rate and the surface pressure acting on the chip at the seizure limit and scratch limit is determined.

As is clear from Figure 5, the gelatinization rate of alumina fiber is 1.
If it is in the range of 0.0 to 50.0%, the scratch limit blood pressure on the chip is 35 to 40 kg/ad, and the seizure limit surface pressure is as high as 70 to 90 kg/c-at. In this case, in the range of alumina fiber gelatinization rate of 30.0 to 40.0%, the surface pressure at the chip's scratch limit is the highest, and the surface pressure at the seizure limit is also high. All you can do is get it.

In addition, in the sliding test, the gelatinization rate of the alumina fiber was 5.
It was confirmed that when it exceeds 0.0%, the amount of alumina fibers that fall off from the aluminum alloy matrix tends to increase, and the alumina fibers that fall off accelerate wear of the chip.

Figure 6 shows the alpha conversion rate of 3.33. Fiber-reinforced aluminum alloys with various alumina fiber volume contents set at 80% and spheroidal graphite cast iron (JIS
The results of a chip-on-disc sliding test with FCD75) are shown. The line (Vla) to (■a) has a gelatinization rate of 3.33.8
In the seizure limit characteristic at 0%, the line (Vlb) ~ (
(b) corresponds to the scratch limit characteristics when the gelatinization rate is 3, 33, and 80%, respectively.

The alloy corresponds to the constituent material of the inner wall portion 1a of the cylinder bore 2, and the tip is formed of this material.

Further, the cast iron corresponds to the constituent material of the compression ring 4,
This material forms a disk.

The test method was to rotate the disk at a speed of 9.5 m/s, and press the sliding surface of the chip knob against the sliding surface of the disk with a specified pressing force without lubrication. The relationship between the volume content and the surface pressure acting on the chip at the seizure limit and scratch limit is determined.

As is clear from Figure 6, when the volume content of alumina fibers with a gelatinization rate of 33% is set to 8.0 to 20.0%, the scratch limit blood pressure in the chip is 30 to 20.0%, as shown by the line (■b). 95 kg/cnl, and the surface pressure at the seizure limit is as high as 70 to 170 kg/cd, as shown by line (■a).

In this case, as already mentioned, if the volume content is less than 8.0%, the seizure resistance etc. will decrease, while on the other hand, if the volume content is less than 8.0%.
If it exceeds 0%, the filling properties of the matrix with respect to the alumina fibers will deteriorate. Therefore, it is appropriate to examine the seizure limit etc. when the volume content of alumina fiber is within the range of 8.0 to 20.0% as described above.

In Figure 6, the lines (X m a ), 0 nib) correspond to the seizure limit characteristics and scratch limit characteristics of a hybrid fiber-reinforced aluminum alloy chip made of a mixture of carbon fiber and alumina fiber with a gelatinization rate of 33%, respectively. do. In this case the volume content of carbon fiber (relative to the total volume of the chip)
is set at 3%.

In this way, in a hybrid type chip, its seizure limit characteristics and scratch limit characteristics are as shown by the line (■a).
, it is clear that the improvement is improved compared to the case of (■b).

However, if the volume content of carbon fiber is less than 3%, the above effect cannot be obtained, and on the other hand, if the volume content exceeds 12%, the total volume content becomes high in relation to the alumina fiber surface.
When a molded article is obtained using the mixed fibers, moldability deteriorates. Therefore, the appropriate volume content of carbon fiber is 3 to 12%.

Figure 7 shows the results of a chip-on-disc wear test between fiber-reinforced aluminum alloys with various alumina fiber volume contents with a pregelatinization rate of 35% and a mating material, spheroidal graphite cast iron (JISFCD75). . Line (IX) corresponds to the wear amount of the alloy, and line (x) corresponds to the wear amount of the cast iron.

The alloy corresponds to the constituent material of the inner wall portion 1a of the cylinder bore 1, and the tip is formed of this material.

Further, the cast iron corresponds to the constituent material of the compression ring 4,
This material forms a disk.

The test method was to rotate the disk at a speed of 2.5 rn/s, press the sliding surface of the chip against the sliding surface of the disk with a pressing force of 20 kg under lubrication, and check the condition! The virtual state was maintained until the sliding distance reached 2000 m. The amount of lubricating oil supplied is 2 to 3 ml! / m.

As is clear from Fig. 7, when the volume content of alumina fiber with a gelatinization rate of 35% is set to 8.0 to 20.0%, the wear amount of the tip decreases from 0.5 to 0, as shown by the line <IX). .85μm
(Also, as shown by the line (X), the amount of wear on the disc is 2.
It becomes less than 85 to 5 μm.

In order to minimize the amount of wear on the chips and disks, it is preferable to set the volume content of alumina fibers to 12.0 to 14.0%.

Figure 8 shows fiber-reinforced aluminum alloys in which the volume content of alumina fibers of various diameters is set at 8% and the gelatinization rate is set at 35%, and the mating material is spheroidal graphite cast iron (JIS).
The results of a chip-on-disc sliding test with FCD75) are shown. The line (X+) is the seizure limit characteristic, and the line (XI
I) respectively correspond to scratch limit characteristics.

The alloy corresponds to the constituent material of the inner wall portion 1a of the cylinder pore 1, and the chip is formed from this material.

Further, cast iron corresponds to the constituent material of the compression ring 4, and the disk is formed from this material. The sliding surfaces of these chips and discs are exposed to force.

Polishing is performed to have various surface roughnesses of 0 μm or more. In this case, the reason why the surface roughness is set to 1.0 μm or more is that it is difficult to obtain a surface roughness lower than that by polishing.

The test I method is to rotate a disk at a speed of 9.5 m/s, press the sliding surface of the 1000 mm against the sliding surface of the disk with a predetermined pressing force without lubrication, and check the surface area of each chip. The relationship between the temperature and the blood pressure acting on the deep tissue at the burn-in limit and scratch limit is determined.

As is clear from Figure 8, the surface roughness of the chip is 1.0~
If it is in the range of 3.0 μm, the surface pressure at the scratch limit is 1
2 to 23 kg/cd, and the blood pressure at the seizure limit is 66.
As high as 1 to 82 kg/ci, practically sufficient sliding characteristics can be obtained.

In such a sliding test between a fiber-reinforced aluminum alloy chip and a cast iron disk, scratching and seizure phenomena are promoted by alumina fibers falling off from the matrix of the chip during the sliding test. Therefore, it is necessary to firmly hold the alumina fibers in the matrix, and in order to satisfy this requirement, it is preferable to set the surface roughness of the chip to approximately one half of the alumina fiber diameter. With this setting, approximately half of the alumina fibers distributed on the sliding surface of the chip with their axes arranged approximately parallel to the sliding surface are embedded in the matrix and held in the matrix. This suppresses the alumina fibers from falling off.

On the other hand, the alumina fibers, which are arranged and dispersed with their axes substantially perpendicular to the sliding surface, are embedded in a large amount in the matrix, so their relationship with the surface roughness is small.

Considering the above points, the alumina fiber diameter should be adjusted to 2°0~6°.
．． When set to Ou nr, the surface roughness of the chip is 1.
It is preferable to set the thickness to 0 to 3.0 μm.

C1 Effect of the invention According to the invention, the gelatinization rate of alumina fibers is 10°0 to 5.
By setting it to 0.0%, the alumina fiber can be made to have high strength and scratch hardness suitable for use in sliding members. In addition, by setting the volume content of alumina fibers having the above-mentioned pregelatinization rate to 8.0 to 20°0%, the sliding part of the aluminum alloy sliding ALJ material can be sufficiently reinforced with fibers, and the sliding It is possible to improve the wear resistance of the sliding part, reduce the amount of wear on the sliding part of the mating material, and further improve the seizure resistance and thermal conductivity.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the cylinder block, Fig. 2 is a plan view of the cylinder block, Fig. 3 is a sectional view taken along the line ■-nl in Fig. 2,
Figure 4 is a graph showing the relationship between the gelatinization rate of alumina fiber and tensile strength, etc. Figure 5 is a graph showing the sliding properties as a relationship between the gelatinization rate of alumina fiber and the surface pressure used in the chip. , 6th
Figure 7 is a graph showing the relationship between the volume content of alumina fiber and surface pressure acting on the chip to show the sliding properties. Figure 7 is a graph showing the relationship between the volume content of alumina fiber and the amount of wear on the chip. FIG. 8 is a graph showing the sliding characteristics in terms of the relationship between the surface roughness of the chip, etc., and the surface pressure acting on the chip. 1... Cylinder block as an aluminum alloy sliding member, 1a... Inner wall of cylinder bore as a sliding part Figure 1 Figure 6 Volume content of aluminum long fibers (F/,) 51)A σ rate of Al-S fiber ('/,) Te-shibu and nursing wear i-(J-Im) procedure amendment (voluntary) September 10, 1988 1. Display of 219 items 1985 Patent Application No. 203967 2, Name of Invention Aluminum Alloy Sliding Member 3, Relationship with the Amendment Case Name of Patent Applicant (532) Honda Motor Co., Ltd. 4, Representative
Director 105 Address 4-4-5 Shinbashi, Minato-ku, Tokyo Nmura Building Telephone 434- Tokyo
4151 5. The "Claims" and "Detailed Description of the Invention" of the specification subject to the amendment, and 5. Please enter the information in 1 below.
)1) Correct. (1) In an aluminum alloy sliding member in which the sliding part is made of a fiber-reinforced aluminum alloy with alumina fibers of fi(is) material, the gelatinization rate of the alumina fibers is io.
, o to 50.0%, and the content of broken alumina fibers are set to 8.0 to 20.0%, respectively. (21 The diameter of the alumina fiber is set to 2.0 to 6.0 μm, and the surface roughness of the sliding portion is set to 1.0 μm based on the diameter.
The aluminum alloy IM moving member according to claim (1), wherein the thickness is set to 0 to 3.0 μm. (3) The gelatinization rate was set at 30.0 to 40.0%.
An aluminum alloy sliding member according to claim (1) or (2). (4) Claims No. (1), (2) or (2) wherein the volume content is set to 12.0 to 14.0%.
3) The aluminum alloy sliding member described in item 3). (5) The aluminum alloy sliding member is a cylinder block for an internal combustion engine, and the sliding part is an inner wall of a cylinder bore.
3) or the aluminum alloy sliding member described in item (4). (2) On page 3, line 5 of the specification, the phrase "used as a dispersion material" is corrected to "used as a reinforcing material." (3) Specification cylinder 3rd line 9th. Correct line 10 as follows. ``In the section, the pregelatinization rate of alumina fiber and the alumina fiber.'' (4) In the 8th line of page 4 of the specification, the phrase ``with respect to the total volume of the sliding part'' is deleted. (5) On page 5, line 18 of the specification, "dispersion material" is corrected to "reinforcement material". (6) Line 13 of page 6 of the specification is corrected as follows. [ refers to long fibers, short fibers, whiskers, etc., for example, I
Manufactured by Cr, product name: Safil, manufactured by DuPont, product name: Fi
ber FP, etc. (7) Page 7, line 17 of the specification, page 9, line 1), line 1)
1” m / on page 18, line 8, page 13, line 8, respectively.
s j is corrected to 1”m/5ecJ. (8) On page 15, line 15 of the specification, the word “use” is corrected to “act”. that's all

Claims (5)

[Claims] (1) In an aluminum alloy sliding member in which the sliding part is made of a fiber-reinforced aluminum alloy with alumina fibers as a dispersion material, the gelatinization rate of the alumina fibers is 10.0 or more.
50.0%, and the volume content of the alumina fibers relative to the total volume of the sliding portion is set to 8.0 to 20.0%, respectively. (2) The diameter of the alumina fiber is set to 2.0 to 6.0 μm, and the surface roughness of the sliding part is set to 1.0 μm based on the diameter.
The aluminum alloy sliding member according to claim (1), wherein the thickness is set to 3.0 μm. (3) The gelatinization rate was set at 30.0 to 40.0%.
An aluminum alloy sliding member according to claim (1) or (2). (4) The aluminum alloy sliding member according to claim (1), (2) or (3), wherein the volume content is set to 12.0 to 14.0%. (5) The aluminum alloy sliding member is a cylinder block for an internal combustion engine, and the sliding part is an inner wall of a cylinder bore.
3) or the aluminum alloy sliding member described in item (4).