JP2003013163A - Sliding member made from powder aluminum alloy, and combination of cylinder and piston ring - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sliding member made from a powder aluminum alloy, superior in abrasion resistance, corrosion resistance, extrudability, and machinability, while little abrading an opposite material. SOLUTION: The sliding member made from the powder aluminum alloy comprises a matrix formed by the powder aluminum alloy, which includes silicon 12-30%, manganese 3-6%, magnesium 1-6%, and the balance substantially aluminum with unavoidable impurities, and which has 30 or more of multiplied value of the mass percentage of silicon by that of manganese; and hard particles dispersed in the matrix, which are one or two of ferrous hard particles and ceramic particles having a lower hardness than that of alumina. A superior wear resistance can be obtained also by improving the abrasion resistance of the aluminum alloy and dispersing hard particles of a comparatively low hardness. The aluminum alloy possesses improved corrosion resistance because of excluding Fe and Cu, and possesses improved elongation and extrudability because of little total added quantity of Si, Fe, Cu, and the like.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a sliding member made of powder aluminum alloy and a combination of a cylinder and a piston. In particular, the present invention relates to a powder aluminum alloy sliding member that can be used for a cylinder liner and a cylinder and a piston that use the powder aluminum alloy sliding member on the inner peripheral sliding surface of the cylinder.

[0002]

2. Description of the Related Art Conventionally, inexpensive cast iron or the like has been used as a cylinder liner material for automobile engines in order to keep manufacturing costs low.

However, in recent years, there has been a demand for reducing the weight of each component in order to improve fuel economy, and similarly for a cylinder liner which is required to have heat resistance and wear resistance, a reduction in weight is also required. Therefore, a sliding member using a light aluminum alloy that can be used for a cylinder liner has been developed in place of an inexpensive gray cast iron.

[0004]

However, when a sliding member made of an aluminum alloy is used in a high temperature, a high surface pressure, a corrosive atmosphere, and a lack of lubrication as in the case where the sliding member made of an aluminum alloy is used in the cylinder liner, the aluminum member made of only the aluminum alloy is used. With the sliding member, the abrasion resistance of the sliding member is insufficient. Therefore, in order to make up for the lack of wear resistance of the aluminum alloy, it has been conventionally performed to contain a hard component having high hardness in the aluminum alloy to ensure the wear resistance of the sliding member made of the aluminum alloy.

For example, in Japanese Patent Application Laid-Open No. 2-120243, a matrix made of an aluminum alloy containing silicon (Si) having a primary crystal size of 10 μm or less, and a mass of a sliding member made of an aluminum alloy dispersed in this matrix. Is defined as 100% and 3 to 5% of alumina particles and 0.
Disclosed is an aluminum alloy sliding member having 5 to 3% of graphite particles, alumina particles having a maximum particle size of 30 μm or less and an average particle size of 10 μm or less, and graphite particles having a maximum particle size of 10 μm or less. Has been done. Further, as an aluminum alloy used for this aluminum alloy sliding member, the mass of the aluminum alloy is 100%, and 16 to 18%.
Si and 4-6% iron (Fe) and 2-4% copper (Cu)
And 0.5-2% magnesium (Mg) and 0.2-0.
5% manganese (Mn) and balance aluminum (Al)
And an aluminum alloy consisting of unavoidable impurities.

Japanese Unexamined Patent Publication No. 2-101140 has an aluminum alloy matrix and hard particles dispersed in the aluminum alloy matrix, and the aluminum alloy matrix has a mass of the aluminum alloy matrix of 100%, and 14. 5% Si and 4.
5% Fe, 2.5% Cu, 0.5% Mg and the balance substantially Al and unavoidable impurities, and hard particles are made of alumina particles, mullite particles, silicon carbide or other ceramic particles. A conventional aluminum alloy sliding member is disclosed.

However, when the insufficient wear resistance of the aluminum alloy sliding member is compensated by a hard component having a high hardness like the aluminum alloy sliding member disclosed herein, the presence of this hard component causes This time, there was a problem that the wear of the mating material was increased. Therefore, the problem of increasing the wear of the mating material has been conventionally dealt with by changing the mating material to a material having excellent wear resistance. Further, since the aluminum sliding member contains a hard component having a high hardness, there is a problem that the workability is poor when the aluminum sliding member is subjected to machining such as cutting and boring.

Further, these aluminum alloy sliding members have poor corrosion resistance, and have a large amount of wear in a corrosive atmosphere as in the case of being used as a cylinder liner material for an engine.
Further, there are problems that elongation and extrudability are poor, and that thermal conductivity is low.

Further, when an aluminum alloy sliding member is used for a cylinder liner, there has been a problem that the low temperature scuffing property is poor. That is, when used at low temperature and under depletion lubrication, aluminum in the aluminum alloy easily plastically flows, so if the shape of the sliding surface does not have oil retention performance, adhesion will easily occur. Was causing scuffing.

Therefore, the surface of the sliding surface of the aluminum alloy sliding member has conventionally been subjected to ECM treatment (Electrochemical M
achining), that is, electrolytic processing. However, this electrolytic processing has a problem that it is necessary to sufficiently perform degreasing as a pretreatment, and uneven treatment is likely to occur. Further, it is necessary to prevent the deterioration of the processing liquid and to prevent the surrounding processing machines from rusting due to the vapor of the processing liquid, which causes a problem that the manufacturing cost increases.

On the other hand, shot blasting, shot peening, etc. cannot obtain the required anti-scuffing property.

The scuffing property also depends on the combination of opposing sliding members. The aluminum alloy used for the sliding member easily adheres as described above. Therefore, it has been pursued that the characteristics of the mating material compensate for this easiness of adhesion.

The present invention has been made in view of the above problems, and an object of the present invention is a powder aluminum alloy slide having excellent wear resistance, corrosion resistance, extrudability, and machinability and having little wear of a mating material. It is to provide a member.

Another object of the present invention is to provide a sliding member made of a powdered aluminum alloy which is further excellent in scuff prevention.

Another object of the present invention is to provide a combination of a cylinder and a piston which is excellent in scuff prevention.

[0016]

Means for Solving the Problems (First Invention) The present inventor has considered the problems of conventional aluminum alloy sliding members as follows. First, the wear of the mating material is large and the machinability is poor. Hard ceramic particles such as alumina and silicon carbide with high hardness are dispersed to secure the wear resistance of the aluminum alloy sliding material. I thought it was the body. Therefore, it was considered that hard particles having a relatively low hardness should be used as the hard particles, and instead the wear resistance of the aluminum alloy itself as the matrix should be improved.

Further, the conventional aluminum alloy sliding member has poor corrosion resistance because the aluminum alloy as a matrix contains Fe and Cu, and also has low thermal conductivity and poor elongation and extrudability. It was thought that this was because the total amount of Si, Fe, Cu, etc. contained in the aluminum alloy was large.

Therefore, as a result of earnest research, the present inventors have found that in a sliding member made of a powder aluminum alloy containing a matrix formed of the powder aluminum alloy and hard particles dispersed in the matrix, the powder aluminum alloy is Assuming that the mass of the aluminum alloy is 100%, 12 to 30% of silicon, 1 to 6% of manganese and 1 to 6%
Of magnesium and the balance consisting essentially of aluminum and unavoidable impurities, and a composition in which the numerical value obtained by multiplying the numerical value of the mass percentage of the silicon and the numerical value of the mass percentage of the manganese is 30 or more, and hard particles Have invented a sliding member made of a powdered aluminum alloy, which is one or more of iron-based hard particles and ceramic particles having a hardness lower than that of alumina.

That is, according to the present invention, by making the composition of the aluminum alloy as the matrix the above-mentioned composition, the wear resistance of the aluminum alloy is improved and the burden of the hard component is reduced, so that it is better than the iron-based hard particles and alumina. Even if hard particles having a relatively low hardness such as ceramic particles having a low hardness are contained, excellent wear resistance can be obtained.

Further, the powder aluminum alloy sliding member of the present invention can improve the corrosion resistance because the aluminum alloy does not contain Fe or Cu. Further, since the total amount of Si, Fe, Cu, etc. contained in the aluminum alloy is small, the elongation and the extrudability can be improved.

From the viewpoint of improving the scuff prevention property, the present inventor may perform the following treatment on the sliding surface of the powder aluminum alloy sliding member of the present invention instead of the conventional EMC treatment. I thought it was preferable.

That is, the inventor of the present invention, in the above-described powder aluminum alloy sliding member of the present invention, has a powder aluminum alloy sliding member in which a large number of recesses are formed on the sliding surface which slides against the mating material by water tablast. Invented

By applying high-pressure water to the sliding surface of the sliding member made of the powder aluminum alloy at a high speed exceeding the speed of sound, the sliding surface of the sliding member made of the powder aluminum alloy is destroyed and a large number of fine particles are formed on the sliding surface. The recesses can be evenly distributed. The minute recesses formed on the sliding surface and uniformly distributed serve as an oil reservoir, and can prevent scuffing.

In addition, the present inventor has found that, in the powder aluminum alloy sliding member of the present invention, a large number of recesses are formed on the sliding surface which slides on the mating material by shot blasting using fine particles coated with either Ni or Sn. The present invention invented a sliding member made of a powdered aluminum alloy in which the Ni coating and the Sn coating were formed together with the above.

Only by shot blasting using fine particles, it is difficult to obtain sufficient anti-scuffing property because of the composition fluidized bed of the powdered aluminum alloy which is the matrix. Also, Ni that is difficult to alloy with aluminum alloys
Alternatively, if Sn is simply coated on the sliding surface of the aluminum alloy sliding member, not only the scuffing prevention property is insufficient, but also Ni or S coated in a short time is used.
The film of n will be worn away. Therefore, shot blasting is performed on the sliding surface using fine particles coated with Ni or Sn to form minute recesses, and at the same time Ni or S is used.
By forming the film of n, the scuffing prevention property can be improved.

(Second Invention) In addition, the present inventor has found that, in a combination of a cylinder and a piston ring, the inner peripheral sliding surface of the cylinder is formed of any of the powder aluminum alloy sliding members of the present invention. The outer peripheral sliding surface of the piston ring that slides with the inner peripheral sliding surface of the
The invention has invented a combination of a cylinder and a piston ring, which is characterized in that either a C / C coating or a resin coating is formed.

When the sliding member made of the powdered aluminum alloy of the present invention is used as the inner peripheral sliding surface of the cylinder, the DLC (diamond
When an ikecarbon) film, a WC / C (nanomicron-order laminate of a tungsten carbide layer and a carbide layer) film, or a resin film is formed, it is possible to prevent the aluminum alloy from adhering. Therefore, it is possible to provide a combination of a cylinder and a piston ring having excellent scuff prevention properties.

[0028]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

(First Invention) A sliding member made of a powder aluminum alloy according to the first invention is a sliding member made of a powder aluminum alloy containing a matrix formed of the powder aluminum alloy and hard particles dispersed in the matrix. In the member, the powder aluminum alloy contains 12 to 30% of silicon (S) based on the mass of the powder aluminum alloy as 100%.
i), 1 to 6% of manganese (Mn), 1 to 6% of magnesium (Mg) and the balance substantially aluminum (Al)
And an unavoidable impurity, and a composition in which the numerical value obtained by multiplying the numerical value of the mass percentage of silicon and the numerical value of the mass percentage of manganese is 30 or more, and the hard particles are harder than the iron-based hard particles and alumina. Is one or more types of ceramic particles having a low

As for the wear resistance of the sliding member made of the powder aluminum alloy of the present invention, the wear resistance is excellent when the content of silicon, manganese and hard particles is large, and the wear resistance is lowered when the content thereof is small.
On the other hand, if the contents of silicon, manganese, and hard particles are too large, manufacturability will decrease. Therefore, in the powder aluminum alloy sliding member of the present invention, the content of silicon is 12
-30%, the manganese content is 1-6%, and the composition is such that the numerical value obtained by multiplying the numerical value of the mass percentage of silicon and the numerical value of the mass percentage of manganese is 30 or more forms a matrix. The wear resistance of the powder aluminum alloy itself is improved so that the load on the hard particles can be reduced. Here, for example, when the mass percentage of silicon is 25% and the mass percentage of manganese is 5%, the numerical value obtained by multiplying the numerical value of the mass percentage of silicon and the numerical value of the mass percentage of manganese is 75.

Further, in the powder aluminum alloy sliding member of the present invention, iron-based hard particles and ceramic particles having a hardness lower than that of alumina are used as the hard particles. That is, the iron-based hard particles are hard particles having a relatively low hardness because they contain iron. Further, ceramic particles having a hardness lower than that of alumina are hard particles having a relatively low hardness. By including these hard particles having a relatively low hardness in the powder aluminum alloy, while ensuring the wear resistance of the sliding member made of the powder aluminum alloy, the aggressiveness to the mating material is reduced and the sliding It is possible to reduce the amount of wear of the mating material at.

The hard particles may be contained in an appropriate amount in consideration of the wear resistance of the sliding member made of the powder aluminum alloy of the present invention and the aggressiveness to the mating material. In this case, the content of the hard particles is preferably 3 to 30% with the sliding member made of the powder aluminum alloy as 100% when the hard particles are composed of only iron-based hard particles. Further, when the hard particles consist only of ceramic particles, the sliding member made of the powdered aluminum alloy is set to 100% to be 1 to 30.
% Is preferable. Further, when the hard particles are composed of iron-based hard particles and ceramic particles, it is preferable that the sliding member made of the powder aluminum alloy is 1% to 30% based on 100%.

When the content of the hard particles is too large, the aggressiveness to the mating material is increased and the wear amount of the mating material is increased. On the contrary, when the content of the hard particles is small, the wear resistance of the powdery aluminum alloy sliding member of the present invention is deteriorated. On the other hand, if the content of the hard particles is too large, the machinability deteriorates and the manufacturing cost increases accordingly.

The iron-based hard particles and the ceramic particles used as the hard particles each preferably have a particle size of 2 to 20 μm. If the particle diameter of the hard particles is less than 2 μm, the wear resistance of the sliding member made of powdered aluminum alloy is reduced, and if it exceeds 20 μm, the aggression to the mating material is increased and the wear amount of the mating material is increased. In addition, the machinability is lowered, and the manufacturing cost is increased.

The hard particles used for the sliding member made of the powdered aluminum alloy of the present invention have a microhardness, that is, MHV (Mic
The ro-Vikers Harness) is preferably less than 2000. The MHV of the alumina particles is 2000, and by using hard particles having an MHV of less than 2000, it is possible to reduce the aggressiveness to the mating material and reduce the wear amount of the mating material.

As the iron-based hard particles, Stellite N is used.
0.1, FeW, FeMo, JPH3, high to low carbon iron chromium (FeCrC) alloy particles can be used. Of these, high to low carbon iron chromium alloy particles are preferably used. The high-to-low carbon alloy particles are hard particles having a relatively low hardness, and can reduce the aggression to the mating material and reduce the wear amount of the mating material, and at the same time improve the resistance of the powder aluminum alloy sliding member. Wearability can be secured.

Further, as the ceramic particles, mulley
G, SiO₂, TiO₂, TiC, Cr ₃C₂, MgO / A
l₂O₃Particles such as can be used. Of these
It is preferable to use light particles. Mullite particles are
It has a lower MHV than the Lumina particles and has an appropriate hardness.
Therefore, it reduces the aggression to the mating material and reduces the wear amount of the mating material.
Can be lowered and made of powder aluminum alloy
The wear resistance of the moving member can be ensured.

In the sliding member made of the powdered aluminum alloy of the present invention, a solid lubricant may be added, if necessary, in addition to the above components. In this case, graphite, carbon, MoS ₂ , BN, glassy carbon or the like can be used as the solid lubricant. Further, it is preferable that the solid lubricant is approximately 5% or less, with the mass of the sliding member made of the powder aluminum alloy of the present invention being approximately 100%. This is because if the solid lubricant is added in an amount of more than 5%, the extrudability during production will be reduced.

The powder aluminum alloy sliding member of the present invention is preferably a powder aluminum alloy sliding member having a large number of recesses formed on the sliding surface that slides on the mating member by water blast.

The large number of recesses formed on the sliding surface of the sliding member made of powdered aluminum alloy can ensure the oil retaining function of the sliding surface by functioning as an oil reservoir. The anti-scuff property of the sliding member can be improved. Further, by applying high-pressure water to the sliding surface, the sliding surface is work hardened, and the wear resistance of the sliding member made of powdered aluminum alloy can be improved accordingly. The water blast can be performed by jetting ultra-high pressure water obtained by an ultra-high pressure water generation pump with a nozzle and applying it to the surface of the sliding surface of the sliding member made of powdered aluminum alloy.

Alternatively, in the sliding member made of the powdered aluminum alloy of the present invention, a large number of concave portions are formed on the sliding surface which slides on the mating material by shot blasting using fine particles coated with either Ni or Sn. It is preferable that the sliding member is made of a powder aluminum alloy on which either the Ni coating or the Sn coating is formed.

By performing shot blasting on the sliding surface using the fine particles coated with Ni or Sn as described above, a large number of concave portions are formed on the sliding surface and adhered to the piston ring or the like which is a sliding partner. It is possible to improve the anti-scuffing property by suppressing the surface exposure of the aluminum alloy, which is easy to form, and forming a Ni or Sn film. Fine particles coated with Ni or Sn may be applied to the sliding surface, and Ni or Sn may be mechanically alloyed with the aluminum alloy (mechanical alloying) to form a Ni or Sn coating film on the sliding surface. Since the Ni or Sn coating is alloyed with the aluminum alloy in the concave portion formed on the sliding surface as described above, it is hard to wear and the scuff prevention property of the powder aluminum alloy sliding member of the present invention is improved. You can

Further, the large number of recesses formed on the sliding surface can ensure the oil retaining function of the sliding surface by playing the role of an oil reservoir, and as a result, the scuff preventing property of the sliding member made of the powder aluminum alloy. Can be improved. Further, by applying fine particles to the sliding surface, the sliding surface is work hardened, and the wear resistance of the powder aluminum alloy sliding member can be improved accordingly.

By applying the fine particles coated with either Ni or Sn to the sliding member made of powdered aluminum alloy in this manner, a large number of minute recesses can be formed on the sliding surface.

The aluminum alloy sliding member of the present invention can be manufactured according to the conventional method for manufacturing an aluminum alloy sliding member. That is, by the air atomizing method, the mass of the powdered aluminum alloy is set to 100% and
2 to 30% of silicon, 1 to 6% of manganese, 1 to 6% of magnesium, and the balance substantially consisting of aluminum and unavoidable impurities, and a numerical value of the mass percentage of silicon and a numerical value of the mass percentage of manganese. Number multiplied by 3
It can be formed by rapidly solidifying aluminum alloy powder having a composition of 0 or more.

Then, one or more kinds of iron-based hard particles such as high to low carbon iron chromium particles and ceramic particles having a hardness lower than that of alumina such as mullite particles are added to the aluminum alloy powder, and a V-type mixer or the like is added. It can be used and mixed uniformly. Then, the uniformly mixed aluminum alloy powder and hard particles can be obtained by using a cold isostatic press or the like to obtain a green compact such as a pellet. Next, the green compact such as the obtained pellet is heated in an electric furnace or the like, and when the temperature of the green compact reaches approximately 400 ° C., it is extruded by an extruder and slid by a powder aluminum alloy of a predetermined shape. The member can be formed.

(Second Invention) A second invention is a combination of a cylinder and a piston ring, wherein an inner peripheral sliding surface of the cylinder is constituted by the sliding member made of the powder aluminum alloy of the first invention. The outer peripheral sliding surface of the piston ring that slides with the inner peripheral sliding surface of the
It is a combination of a cylinder and a piston ring, characterized in that either a C coating or a resin coating is formed.

Since the inner peripheral sliding surface of the cylinder in the combination of the cylinder and the piston ring of the present invention is constituted by the sliding member made of the powder aluminum alloy of the first invention, the description of this portion will be made in the first invention. Let's turn to the explanation.

The outer peripheral sliding surface of the piston ring can be manufactured by using a commonly used method. A nitriding layer is formed on the surface of a commonly used piston ring by nitriding. And PVD method, CVD method, plasma C
The DLC film and the WC / C film can be formed by using the VD method or the like.

By thus forming the DLC film, the WC / C film, and the resin film on the outer peripheral sliding surface of the piston ring, which is the mating member of the cylinder, the first outer peripheral sliding surface of the cylinder used. It is possible to make the sliding member made of the powder aluminum alloy of the invention hard to adhere to the powder aluminum alloy. As a result, the scuff prevention property can be improved.

The wear resistance of the piston ring can be improved by forming a DLC film, a WC, and a resin film on the outer peripheral sliding surface of the piston ring. By forming these coatings on the piston ring, an excellent friction coefficient (μ) can be obtained.

[0052]

EXAMPLES As the following examples, the powder aluminum alloy sliding member of the present invention was manufactured and various evaluation tests were conducted.
This will be described below.

(First Evaluation Test: Evaluation of Abrasion Resistance and Aggressiveness of Counterpart Material) Using a LFW-1 abrasion tester, sliding member made of powder aluminum alloy of the present invention (hereinafter referred to as “invention material”) and comparison. The wear amount of the sliding member (hereinafter referred to as "comparative material") and the wear amount of the mating member were measured. The wear resistance of the material of the present invention and the comparative material was evaluated, and the aggression property of the partner material was evaluated from the wear amount of the mating material.

In this evaluation test, the material of the present invention and the comparative material were used as test rings, and the mating material was used as a test block. The amount of wear was measured by measuring the wear depth of the test ring and test block after the test. Note that the materials of the present invention and the comparative material are used as the bore surface of the cylinder, so that the material is a bore material, and the mating material is used as a piston ring. The compositions and measurement results of the material of the present invention and the comparative material are shown in Table 1.

[0055]

[Table 1]

The test ring material of the present invention and the comparative material were manufactured as follows. An aluminum alloy powder having a composition shown in Table 1 and having a particle size of 42 mesh or less was rapidly cooled and solidified by an air atomizing method. Next, the hard particles shown in Table 1 were added to this aluminum alloy powder and uniformly mixed with a rotary blade type mixer. By cold isostatic pressing the mixed aluminum alloy powder,
A pellet having a diameter of 170 mm and a length of 300 mm was produced. This pellet was heated to 400 ° C. in an electric furnace, and a round bar extruded material having a diameter of 65 mm was immediately produced by an indirect extruder.

Next, this round bar extruded material was machined and
The outer diameter of the invention material and comparative material shown in
A test ring having m and an axial length of 11 mm was produced. The test block of the mating material is SU whose surface is nitrided.
The S440B material was used. The size is 6.3 mm (length) x 1
It was 5.7 mm (width) x 10 mm (height).

This evaluation test was conducted as follows. The test ring was arranged on the lower side, and the test block was arranged on the upper side of the test ring so as to contact the test ring.
While the test ring was bathed in the base oil of 5W-30 standard used as a lubricating oil, the test block was pressed against the test ring with a load of 1764N for 160r.
After rotating for 30 minutes at a rotation speed of pm, the resulting wear depth of the test ring and the test block was measured. The oil temperature of the lubricating oil was room temperature.

First, the wear resistance of the material of the present invention and the comparative material will be examined.

Material No. 3 of the present invention has the smallest amount of wear and the wear depth is 0.6 μm. After that, the present invention material No. 4 has a wear depth of 0.8 μm, the present invention material No. 2 has a wear depth of 0.9 μm, the present invention material No. 5 has a wear depth of 1.0 μm, and the comparative material No. 3 has wear. The depth is 1.3 μm, and the wear depth of the present invention material No. 1 is 2.3 μm. In both of the present invention material and the comparative material, the Si content is in the range of 12 to 30% and the Mn content is 1 to 6% with the mass of the powder aluminum alloy as 100%.
, The content of Mg is between 1 and 6%, and the numerical value obtained by multiplying the numerical value of the mass percentage of Si and the numerical value of the mass percentage of Mn is 30 or more. Moreover, all contain hard particles.

On the other hand, Comparative Material No. 1 and Comparative Material No. 2 have wear depths of 48.2 μm and 23.9 μm, respectively, and have a large amount of wear and low wear resistance. In all of these comparative materials, the Si content is between 12 and 30%, and the Mn content is between 1 and 30%.
Between 6%, the content of Mg is between 1-6%,
Moreover, the numerical value obtained by multiplying the numerical value of the mass percentage of Si and the numerical value of the mass percentage of Mn is 30 or more, but none of them contains hard particles. Further, Comparative Material No. 9 has a wear depth of 35.3 μm and also has low wear resistance. This comparative material No. 9 also contained neither hard particles nor Mn. From these facts, it can be seen that the presence of hard particles is effective in ensuring wear resistance.

Comparative material No. 4, comparative material No. 6 and comparative material N
o.8 has wear depths of 15.2 μm, 29.3 μm and 1
It is 0.3 μm. Hard particles are added to all of these. However, in both Comparative Material No. 4 and Comparative Material No. 6, the content of Si is between 12 and 30%, the content of Mn is between 1 and 6%, and the content of Mg is 1 The value obtained by multiplying the numerical value of the mass percentage of Si and the numerical value of the mass percentage of Mn is 12 and 15, but is between 3 and 6%, and 3
Not 0 or more. Comparative material No. 8 has a Si content of 4
Although it is 0%, Mn is not contained. Therefore, the numerical value obtained by multiplying the numerical value of the mass percentage of Si and the numerical value of the mass percentage of Mn is 0. From these facts, the Si content is in the range of 12 to 30%, the Mn content is in the range of 1 to 6%, the Mg content is in the range of 1 to 6%, and S
It can be seen that when the value obtained by multiplying the numerical value of the mass percentage of i and the numerical value of the mass percentage of Mn is 30 or more, it is effective in ensuring the wear resistance of the aluminum powder alloy itself which is the matrix.

Further, comparing the comparative material No. 1 with the comparative material No. 2, it can be seen that the comparative material No. 2 having a larger content of Si and Mn has improved wear resistance. It can be seen that the wear resistance of the powder aluminum alloy itself can be improved by increasing the contents of Si and Mn, and the wear resistance of the powder aluminum alloy itself can be improved by containing Mn.

That is, generally, the content of Si is between 12 and 30%, the content of Mn is between 1 and 6%, and the content of Mg is 1 with the mass of the powdered aluminum alloy as 100%. If it is between 6% and 6 and the numerical value obtained by multiplying the numerical value of the mass percentage of Si and the numerical value of the mass percentage of Mn is 30 or more and further contains hard particles, the aluminum powder alloy slide It can be seen that the dynamic member has excellent wear resistance.

Next, the opponent attack of the material of the present invention and the comparative material, that is, the amount of wear of the opponent material will be examined.

Inventive Material No. 1, Inventive Material No. 2, Inventive Material N
o.3, Inventive material No. 4, Inventive material No. 5, Inventive material No. 6, Inventive material No. 7 and Inventive material No. 8 are wear depth of mating material (ring material) 2.6 μm, 2.1 μm, 0.4 μ respectively
m, 0.7 μm, 1.1 μm, 1.4 μm, 0.7 μm
And 0.8 μm. Neither contains iron,
The hard particles include carbon iron chromium alloy (FeCrC) particles or mullite particles.

When the comparative materials were examined, the comparative materials No. 5 and No. 8 containing no iron and using only alumina as hard particles had the wear depths of the mating materials of 6.6 μm and 6.1 μm. Has become. From these facts, it is considered that the use of relatively hard hard particles such as alumina among the hard particles will increase the wear of the mating material.

Further, in Comparative Material No. 3, Comparative Material No. 4 and Comparative Material No. 7, which contained both iron and alumina, the wear depths of the mating materials were 7.1 μm, 6.3 μm and 5. It is 2 μm, and the wear of the mating material is also large. On the other hand, the comparative material No. 6, which does not contain iron and contains mullite as hard particles, has a wear depth of the mating material of 0.5 μm.
Therefore, the amount of wear of the mating material is small. From these facts, it is considered that the presence of iron and alumina increases the amount of wear of the mating material. Further, even if the hard particles are added together as in the comparative material No. 3 and the comparative material No. 4, since the alumina is contained, it is considered that the amount of wear of the mating material is large.

(Second Evaluation Test: Evaluation of Abrasion Resistance in Corrosive Atmosphere and Attack of Counterpart Material) A sliding member made of the powder aluminum alloy of the present invention in a corrosive atmosphere (hereinafter referred to as " The wear amount of the sliding member (hereinafter referred to as "comparative material") for comparison and the wear amount of the mating material were measured to evaluate the wear resistance and the attacking property of the mating material. The outline of this evaluation test is shown in FIG.

In this evaluation test, a lower sample A was used as the material for the bore surface of the cylinder liner, that is, the present invention material and the comparative material which are cylinder bore materials. The lower sample A
A piston ring material was cut out as a mating material of the above and used as an upper test piece B. The amount of wear was measured by measuring the wear depth of the lower and upper test pieces after the test. The compositions and measurement results of the present invention material and the comparative material are shown in Table 2.

[0071]

[Table 2]

The material of the present invention and the comparative material of the lower test piece A of this evaluation test were manufactured as follows.

First, as in the case of the first evaluation test, by using the air atomizing method, the composition shown in Table 2 was
It was produced by rapidly solidifying aluminum alloy powder having a grain size of 2 mesh or less. Next, Table 1
The hard particles shown in 1 above were added and uniformly mixed with a rotary blade mixer. The mixed aluminum alloy powder was subjected to cold isostatic pressing to prepare a pellet having a diameter of 170 mm and a length of 300 mm. This pellet was heated to 400 ° C. in an electric furnace, and a round bar extruded material having a diameter of 65 mm was immediately produced by an indirect extruder.

Next, this extruded material was machined to a size of 30 mm × 30 mm composed of the material of the present invention and the comparative material shown in Table 2.
A lower sample A of × 5 mm (plate thickness) was produced.

As the upper test piece B of the mating material, the bore diameter is 85 m.
SUS440B gas nitriding piston ring for m length 1
The one cut into 5 mm was used.

This evaluation test was conducted as follows. First, the lower test piece A is arranged on the lower side, and the upper test piece B is arranged on the upper side thereof so as to come into contact with the lower test piece A. It was impregnated with a 20% aqueous sulfuric acid solution. Then, while pressing the upper test piece B against the lower test piece A with a load of 50 N in this state, the lower test piece is rotated for 30 minutes at a rotation speed of 0.6 m / s, and the lower test piece A and the upper test piece at that time are rotated. The wear depth of the sample B was measured.

The wear depth of the material No. 3 of the present invention is 2.2 μm, while the wear depth of the comparative material No. 7, the comparative material No. 9 and the comparative material No. 1
Wear depths of 0 are 17.1 μm and 22.1 μm, respectively
And 10.1 μm. The material No. 3 of the present invention which does not contain Fe and Cu is at least 1 of Fe and Cu.
It can be seen that the wear resistance is superior even in a corrosive atmosphere to these comparative materials containing at least one kind.

The wear depth of the mating material is 3.0 μm in the material No. 3 of the present invention, while in the material No. 3 of the present invention, in the material No. 7, the comparative material No. 9 and the material No. 10 of the comparison, 51.4 each
μm, 0.0 μm and 30.6 μm. Comparative material N containing alumina particles or SiC particles as hard particles and Fe in the composition of the powder aluminum alloy
It can be seen that o.7 and comparative material No. 10 have a large attacking property of the mating material and a large amount of wear of the mating material. On the other hand, the comparative material No. 9 containing no Fe and containing no hard particles has no wear amount of the mating material.

From these facts, when one or more of Fe and Cu is contained, the wear resistance in a corrosive atmosphere decreases,
Further, it is found that the amount of wear of the mating material becomes large when Fe is contained and when alumina and SiC which are relatively hard among the hard particles are contained.

(Third Evaluation Test: Evaluation of Scuffing Prevention Property Under Exhaust Lubrication) A sliding member made of the powder aluminum alloy of the present invention (hereinafter referred to as "material of the present invention") was tested using a reciprocating wear tester.
For comparison, a sliding member (hereinafter referred to as "comparative material") was slid on the piston ring material to evaluate the scuffing prevention property. The outline of this evaluation test is shown in FIG. In the present evaluation test, the lower test piece C is obtained by subjecting the material of the present invention and the comparative material, which can be used for the cylinder bore material, to finishing,
An upper test piece D was obtained by cutting out the piston ring material and subjecting it to surface treatment. The anti-scuffing property was evaluated by measuring the time from the start of this evaluation test to the time when the friction coefficient rapidly increased and the scuffing occurred. Table 3 shows the combination of the lower test piece C and the upper test piece D used in this evaluation test and the measurement results. The roughness in Table 3 is shown as a ten-point average roughness (Rz).

[0081]

[Table 3]

Material Nos. 3 and 8 of the present invention used as the lower test piece C were prepared in the same manner as in the second evaluation test.
It was created in the same shape. Therefore, the shape is 30
It is mm × 30 mm × 5 mm (plate thickness). The material of the present invention
The compositions of No. 3 and invention material No. 8 are as shown in Table 1. Further, the finishing processing methods shown in Table 3 were applied to the surfaces of the invention material No. 3 and the invention material No. 8 thus produced. That is, finish honing, fine shot Ni coat finish, fine shot Sn coat finish, water blast treatment finish, and fine shot finish were performed. Here, "water blast treatment finish" refers to a treatment method in which a large number of recesses are formed on the sliding surface by water blast, and "fine grain shot Ni coat finish" means surface treatment by shot blast using fine particles coated with Ni. The treatment method of forming a large number of concave portions and a Ni coating on the surface is "fine-grain shot Sn coat finish", which means that a large number of concave portions are formed on a sliding surface that slides on a mating material by shot blasting using Sn-coated fine particles. It refers to a treatment method of forming a recess and forming a Sn coating.
"Fine grain shot finish" refers to normal shot blasting.

Cast iron F230 and aluminum alloy A390.T6 were used as comparative materials for the lower test piece C. Cast iron F2
The surface of 30 was subjected to finishing honing. Also A39
The surface of 0 · T6 was subjected to electrolytic processing (ECM).
The shape was the same as that of the material of the present invention used in this evaluation test.
Note that A390 is an Al-Si-Cu-Mg alloy, where the total mass is 100%, Si is 17%, Cu is
Is 4.5%, Mg is 0.5%, and the balance is Al.

As the upper test piece D used as the piston ring material, a piston ring made of SUS440B gas nitriding for a bore diameter of 85 mm and cut to a length of 15 mm was used.

As shown in Table 3, the surface treatment is a surface treatment by simply performing a nitriding treatment and a surface treatment by performing a nitriding treatment and then plating chromium (Cr) thereon.

In the test, the lower test piece C was reciprocated at a reciprocating distance of 30 mm while the upper test piece D was contacted so that the tip of the upper test piece D was perpendicular to the surface of the lower test piece C and the upper test piece D was weighted with 49 N. Reciprocation was carried out at a reciprocating speed of 7 Hz, and the time when the friction coefficient suddenly increased was measured. As the lubricating oil, 5w30 base oil was used, and only a small amount was applied to the sliding surface of the lower test piece C before the test, and it was not replenished until the end of the test. The temperature was room temperature.

The finishing method for the lower test piece C in the combinations No. 1, No. 2 and No. 3 is finishing honing. The surface treatment of the upper sample D, which is the counterpart of the lower sample C, is resin coating, WC / C coating, and DLC coating, respectively. In case of combination No.7, further No.8
The time for the friction coefficient to rise sharply is longer than in the case. From this, it can be seen that forming a resin coating, a WC / C coating, or a DLC coating on the piston ring material, which is the counterpart of the cylinder bore material produced using the material of the present invention, helps prevent scuffing. That is, even if the cylinder bore material is mirror-finished, the piston ring is coated with resin, WC
It is considered that the anti-scuffing property is improved by forming the / C coat and the DLC coat.

Combination No.4, No.5, No.6, No.7, No.8
In the above, all of the lower side specimens are No. 8 materials of the present invention, and the surface treatment of the upper side specimen D, which is the mating material, is nitriding treatment. However, the finishing method of the lower sample C in the combinations No. 4, No. 5 and No. 6 is fine grain shot Ni coat finish, fine grain shot Sn coat finish and water blast treatment finish, respectively. The time of sudden rise is after 25 minutes or more have passed. On the other hand, in the combinations No. 7 and No. 8, the finishing method of the lower test piece C is finish honing and fine grain shot finishing, respectively, and the time when the friction coefficient suddenly increases is less than 2 minutes. It is as short as 4 minutes.

When fine grain shot Ni coat finish, fine grain shot Sn coat finish and water blast treatment finish and finish honing are compared, fine grain shot N
It can be said that the i-coat finish, the fine-grain shot Sn coat finish, the water blast treatment finish, and the like are more excellent in the scuff prevention property than the finish honing. It is considered that the finish honing has insufficient scuffing resistance because the surface tends to be mirror-finished. Further, fine grain shots have improved scuffing prevention properties as compared with finish honing, but it is considered to be still insufficient as compared with fine grain shots Sn coat finish and water blast treatment finish. From these facts, it is understood that the scuff prevention property can be improved by subjecting the cylinder bore material produced by using the material of the present invention to the fine shot Ni coat finish, the fine shot Sn coat finish and the water blast treatment finish.

The combinations No. 9, No. 10 and No. 11 have a shorter time until the friction coefficient suddenly increases depending on the combinations No. 4, No. 5 and No. 6. Combination No. 7
When comparing No. 10 with No. 10, the other two are the same except for the material of the cylinder bore material. Even in this case, the combination No. 7 using the material No. 8 of the present invention has a longer time in which the friction coefficient sharply increases. Therefore, it is considered that the material of the present invention has improved scuffing resistance as compared with the conventional cast iron.

The fine grain shot Ni coat finish, the fine grain shot Sn coat finish and the water blast treatment finish can be applied to the material of the present invention by using conventional cast iron or A3.
It can be considered that the anti-scuffing property can be improved as compared with the case of using 90T6.

(Fourth Evaluation Test: Evaluation of Friction Characteristics) Similar to the evaluation test of the scuff prevention property under the depletion lubrication described above, the sliding motion made of the powder aluminum alloy of the present invention was measured by using the reciprocating wear tester. Friction characteristics were evaluated by sliding a member (hereinafter referred to as "material of the present invention") and a sliding member (hereinafter referred to as "comparative material") for comparison with a piston ring material.

An outline of this evaluation test can be shown by using FIG. 2 as in the third evaluation test. Also in this evaluation test, a lower test piece C was obtained by finishing the present invention material and the comparative material which can be used as the cylinder bore material, and the piston ring material was cut out to obtain an upper test piece D. The friction characteristics were evaluated by measuring the friction coefficient when the friction coefficient (μ) became stable after starting this evaluation test.

The combination of the material of the lower test piece C, its finishing method and the surface roughness and the surface treatment method of the material used as the upper test piece D, except for the combination No. 12, is the third.
Selected from the combinations in the evaluation test. The combinations and the measurement results are shown in Table 4. That is, No. 1, No.
No. 7, No. 9 and No. 11 are the same combination as the third evaluation test, and No. 12 is a new combination.

Since the manufacturing method and the shape of the lower sample C and the upper sample D for each combination are the same as those in the third evaluation test, the description in the third evaluation test will be omitted.

[0096]

[Table 4]

In this evaluation test, 5 used as a lubricating oil was used.
While the base oil of W-30 standard is in an oil bath, the tip of the upper test piece D is contacted so as to be perpendicular to the surface of the lower test piece C, and the upper test piece D is weighted with 49N while the lower test piece is being weighted. The piece C was reciprocated at a reciprocating distance of 40 mm and a reciprocating speed of 5 Hz to measure the friction coefficient when the friction coefficient became stable. The oil temperature of the lubricating oil was room temperature.

The combinations No. 1 and No. 7 use the present invention material No. 3 and the present invention material No. 8, respectively, and both have finish honing on the surface. The surface treatment of the mating piston ring is resin coating for combination No. 1 and nitriding for combination No. 7. An excellent friction coefficient can be obtained regardless of whether the mating material is a resin coat or a nitriding treatment. It is considered that the friction coefficient is smaller than that of the combinations No. 9, No. 12 and No. 11 using the comparative material, because the surface by finish honing can be mirror-finished and the shearing force at the adhesion part is small.

When the cast iron FC230 used in the combinations No. 9 and No. 12 is the finish honing, the friction coefficient is large even if the mating material is plated with Cr. It is considered that the cast iron FC230 is hard to be mirror-finished and has a large friction coefficient due to the material having a large shearing force at the adhesion portion. Incidentally, in the combinations No. 9 and No. 12, the surface roughness of the finish-honed cast iron FC230 is different. The combination No. 9 having a larger roughness has a larger friction coefficient than the combination No. 7.

(Fifth Evaluation Test: Evaluation of Manufacturability, etc.) Inventive Material No. 1, Inventive Material No. 3, Inventive Material No. 7, Inventive Material No. 8,
Manufacturability was evaluated for Comparative Material No. 3, Comparative Material No. 7, Comparative Material No. 8 and Comparative Material No. 9. The evaluation of the manufacturability was judged by the extrusion initial pressure at the time of extrusion into the long material extruder and cracks, galling on the surface of the extruded long material, and the result of observation of the finished state. The extrudability was evaluated from the initial extrusion pressure, the surface cracks, galling, and the workability were evaluated from the observation of the finished state, and both were combined to evaluate the manufacturability. That is, when both extrudability and processability are good, manufacturability is considered to be good.
And When the extrudability was not a problem, but the processability was a problem, the manufacturability was considered to be slightly good, and the result was rated as “good”. When there was a problem in extrudability and could not be extruded, or there was a problem in both extrudability and processability, the manufacturability was considered to be poor, and the result was marked with x.

The manufacturing method was the same as the manufacturing method shown in the first evaluation test until it was extruded by the long material extruder. Therefore, the description of that portion will be omitted from the description in the first evaluation test. The manufactured long material was a thin pipe-shaped long material.

Table 5 shows the compositions and evaluation results of the material of the present invention and the comparative material used in this evaluation test.

[0103]

[Table 5]

All the materials of the present invention have good extrudability. That is, it is considered that there is no problem in the extrudability of not only thick materials but also thin materials.

In contrast, Comparative Material No. 3, Comparative Material No. 7, Comparative Material No. 8 and Comparative Material No. 9 were all poor in manufacturability.
It can be seen that these have no problem for thick and long materials, but have problems for thin materials. Comparative material No.3, comparative material
For No. 7 and comparative material No. 8, it is considered that the presence of alumina affects the extrudability. Regarding Comparative Material No. 9, it is considered that the presence of Cu increases the hardness and reduces the elongation.

(Sixth Evaluation Test: Evaluation of Thermal Conductivity) Further, the thermal conductivity of the material of the present invention was measured to evaluate the thermal conductivity. For comparison, the thermal conductivity of the comparative material was measured. Table 6 shows the composition and thermal conductivity of the material of the present invention and the comparative material used in this evaluation test.

The manufacturing method and shape of the material of the present invention and the comparative material used in this evaluation test are the same as those in the evaluation test of wear resistance and opponent material attack. Therefore, the description of the manufacturing method and the shape will be omitted in the description of the first evaluation test.

[0108]

[Table 6]

As described above, it can be said that the sliding member made of the powder aluminum alloy of the present invention has excellent thermal conductivity when it has the compositions of Inventive Material No. 7 and Inventive Material No. 9.

[0110]

The sliding member made of the powder aluminum alloy of the present invention can have excellent wear resistance and can reduce the amount of wear of the mating material. Furthermore, it can have excellent manufacturability.

In the sliding member made of the powdered aluminum alloy of the present invention, the scuff prevention property is improved by forming a large number of recesses on the sliding surface which slides with the mating material by water tablast. You can

Furthermore, in the powder aluminum alloy sliding member of the present invention, a large number of concave portions are formed on the sliding surface which slides on the mating material by shot blasting using fine particles coated with either Ni or Sn and Ni. By forming either the coating or the Sn coating, the scuff prevention can be improved.

The combination of the cylinder and the piston ring of the present invention can have excellent anti-scuffing property.

[Brief description of drawings]

FIG. 1 is a diagram showing an outline of a second evaluation test.

FIG. 2 is a diagram showing an outline of a third evaluation test and a fourth evaluation test.

[Explanation of symbols]

A: Lower sample B: Upper sample C: Lower sample D: Upper sample

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) C23C 28/00 C23C 28/00 C F02F 1/00 F02F 1/00 D G 5/00 5/00 5 F F Term (reference) 3G024 AA22 FA00 FA06 FA09 GA00 GA08 GA18 HA07 HA10 4K018 AA16 AB01 BA08 BA13 BA20 BB04 FA01 FA05 FA24 FA25 KA02 KA08 KA09 4K044 AA06 AB03 AB04 AB10 BA06 BA10 BA18 CB02 BB03 BC01 CA12 CA13 CA14 CA23 CA23 CA14 CA23

Claims (11)

[Claims] 1. A sliding member made of a powder aluminum alloy, comprising a matrix formed of the powder aluminum alloy and hard particles dispersed in the matrix, wherein the powder aluminum alloy has a mass of the powder aluminum alloy of 100%. As 12 to 30% of silicon and 1 to
6% manganese, 1-6% magnesium and the balance substantially aluminum and inevitable impurities, and the numerical value obtained by multiplying the numerical value of the mass percentage of the silicon by the numerical value of the mass percentage of the manganese is 30. The composition is as described above, and the hard particles are one or more of iron-based hard particles and ceramic particles having a hardness lower than that of alumina, and a sliding member made of a powder aluminum alloy. 2. When the hard particles are composed of only the iron-based hard particles, the content of the hard particles is 3 to 10 with the mass of the sliding member made of the powder aluminum alloy being 100%.
The sliding member made of the powder aluminum alloy according to claim 1, which has a content of 30%. 3. When the hard particles are composed of only the ceramic particles, the content of the hard particles is 1 to 30% with the mass of the powder aluminum alloy sliding member being 100%. The sliding member made of the powder aluminum alloy according to 1. 4. When the hard particles are composed of the iron-based hard particles and the ceramic particles, the content of the hard particles is 1 to 100% by mass of the sliding member made of the powder aluminum alloy. The sliding member made of the powder aluminum alloy according to claim 1, which has a content of 30%. 5. The powdered aluminum sliding member according to claim 1, 2, 3 or 4, wherein the hard particles have an MHV of less than 2000. 6. The powder aluminum alloy sliding member according to claim 1, wherein the iron-based hard particles are high to low carbon iron chromium alloy particles. 7. The sliding member made of a powder aluminum alloy according to claim 1, wherein the ceramic particles are mullite particles. 8. The average particle diameter of the hard particles is 2 to 20 μm.
The sliding member made of a powdered aluminum alloy according to claim 1, wherein the sliding member is m. 9. A plurality of recesses are formed on a sliding surface that slides on a mating member by water tablast.
A sliding member made of powder aluminum alloy according to 3, 4, 5, 6, 7 or 8. 10. A large number of concave portions are formed on a sliding surface which slides on a mating material by shot blasting using fine particles coated with either Ni or Sn, and Ni.
A coating film or a Sn coating film is formed,
A sliding member made of powder aluminum alloy according to 2, 3, 4, 5, 6, 7 or 8. 11. A combination of a cylinder and a piston ring, wherein the inner peripheral sliding surface of the cylinder has the above-mentioned 1, 2, 3,
An outer peripheral slide of the piston ring, which is constituted by the powder aluminum alloy sliding member described in any one of 4, 5, 6, 7, 8, 9, and 10, and slides on the inner peripheral sliding surface of the cylinder. A combination of a cylinder and a piston ring, characterized in that the moving surface is formed with any one of a DLC film, a WC / C film and a resin film.