JPH03117779A - Slide member - Google Patents

Abstract

PURPOSE:To reduce abration of a first member and a second member by dispos ing primary crystal Si forming a circular arc and protruding in hyper-eutectic Al-Si alloy at least at a slide surface part of the first member to come into contact with the second member, and applying a composite dispersion plating process at a slide surface part of the second member to the first member. CONSTITUTION:For a slide member including a first member and a second member to come into contact with each other slide relative to each other, at least a slide surface of the first member to the second member has primary crystal Si which contributes to abrasion resistance in hyper-eutectic Al-Si alloy forming a circular arc without surface cracking or removal. In addition, the primary crystal Si in the form of the circular arc is protruded in a range of 1-6mum by etching Al foundation. A composite dispersion plating process is applied to at least a slide surface part of the second member to the first mem ber. Both of the first and the second members to come into contact with each other to slide relatively have less abrasion to have a good abrasion resistance, thereby the durability is improved.

Description

[Detailed description of the invention] [Purpose of the invention]

(Industrial Application Field) This invention is suitable for use as a sliding member when two members come into contact with each other and slide relative to each other, and has wear resistance from room temperature to high temperatures of about 250°C. The present invention relates to a sliding member that is in good condition, has a small amount of wear, and has excellent durability. (Prior Art) Conventionally, there have been various combinations of sliding members when two members come into contact with each other and slide relative to each other. For example, at least one member is made of steel material. There are various types of materials, such as those made of a copper alloy material, and those made of an aluminum alloy material. When one of these members is made of an aluminum alloy material, for example, the sliding surface of the member made of the aluminum alloy material is polished and then etched with a mixture of NaOH, H2O2, and water. The silicon particles were raised and then washed with water, and then the surface of the silicon particles exposed on the sliding surface was etched with a mixture of HNO3 and water to dissolve and smooth the surface of the silicon particles (JP-A-59 -107081 Publication), aluminum alloy sliding surface polished with a specific grindstone (
JP-A-61-230871, JP-A-62-249
No. 69) and by applying a shot blast finish to the surface of a sliding member made of a fiber composite material with an aluminum alloy as a matrix, the aluminum alloy on the surface is selectively removed and silicon particles and fibers are made to protrude from the surface. , in which four parts are formed on the surface between the protruding silicon particles or m fibers, and then the surface is mechanically polished (Japanese Patent Application Laid-open No. 63
207528), and the sliding surface portion of a sliding member in which primary crystal Si is protruded by conventional grinding has a surface metallographic structure as shown in FIG. (Problems to be Solved by the Invention) However, in such conventional sliding members made of aluminum alloy, primary crystal S, which contributes to wear resistance,
By making i protrude from the surface, 11 abrasion resistance is improved, but depending on the mating material, the amount of wear of the mating material may increase due to sliding with the aluminum alloy, A problem has been that wear of the aluminum alloy may also increase due to wear. (Object of the Invention) The present invention has been made in view of such conventional problems, and includes a first member and a second member that abut each other and slide relative to each other. In the sliding member, at least the sliding surface portion relative to the second member is made of an aluminum alloy, and both the first member and the second member have a small amount of wear and have excellent wear resistance. The purpose is to provide a sliding member.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a sliding member having a first member and a second member that are in contact with each other and slide relative to each other, wherein at least the second member of the first member The sliding surface against the member has an arcuate shape in which the primary crystal Si, which contributes to wear resistance in the hypereutectic An-3t alloy, does not cause surface cracking or falling off. The structure is characterized in that crystalline Si protrudes in a range of 1 to 6 μm, and at least the sliding surface of the second member relative to the first member is subjected to a composite dispersion plating treatment. The structure of the sliding member is used as a means to solve the above-mentioned conventional problems. In the sliding member according to the present invention, the sliding surface portion of the first member relative to at least the second member is made of hypereutectic An-
In the 3i alloy, the primary crystal Si, which contributes to improving wear resistance, forms an arc shape without causing surface cracking or falling off. This can be done by grinding using 1 elastic paper stone. The elastic whetstone used in this case is oxide or carbide. Abrasive grains made of mixed particles selected from various particles such as nitrides, diamonds, iron sand, metal grains, etc. are held with appropriate elasticity by a flexible resin made of flexible epoxy resin, urethane resin, etc. things are used. By performing the grinding process using such an elastic grindstone, the relatively soft aluminum alloy base is ground, and the relatively hard initial Si is ground into an arc shape. Further, the sliding surface of the first member is etched with respect to the An base, so that the arc-shaped primary crystal Si protrudes from the surface of the An base within a range of 1 to 6 pm. ing. In this case, an alkaline or acidic etching solution is used, and more specifically, an alkaline etching solution such as sodium hydroxide, or an acidic etching solution such as phosphoric acid, sulfuric acid, nitric acid, or hydrochloric acid is used. By performing electrolytic and chemical polishing using these etching solutions, the arcuate primary Si crystals are made to protrude from the sliding surface by a range of 1 to 6 JLm, more preferably 4 to 6 JLm. In this way, by making the primary Si crystals protruding from the surface into an arc shape, there are no corners, so that the primary Si crystals that protrude from the surface are not affected by the shearing force or impact force generated between it and the second member, which is the mating material. This makes it difficult for crystalline Si to be missing. Furthermore, under friction conditions where the lubricating oil film is thin, if the protruding height of primary Si is large, the lubricating oil film is likely to break, and metal contact with the second member is likely to occur. By making the surface of the initial Si material, which has a high deformation resistance, have an arc shape, it is possible to reduce the contact area with the second member, thereby preventing damage to the second member due to oil film rupture. As a result, the frictional force is reduced, and primary Si crystals are less likely to crack or fall off. This greatly contributes to improving the wear resistance in high-temperature atmospheres ranging from room temperature to 250° C., where the oil film thickness becomes thinner, that is, the viscosity of the lubricating oil becomes lower. However, if the protrusion height of primary Si is smaller than lILm, the protrusion height is insufficient, so sufficient wear resistance cannot be obtained, especially in a high-temperature atmosphere ranging from room temperature to about 250°C. In order to obtain more sufficient wear resistance, it is particularly desirable that the protrusion height be 4 JLm or more. On the other hand, if the protrusion height is greater than 6 μm, it is not preferable because the protrusion height is too large and the protruding primary Si is likely to be broken even by a slight frictional force. Furthermore, during sliding in a high-temperature atmosphere, the elastic deformation region of the AfL base becomes narrower, and the protruding primary Si tends to be buried in the Au base. If it is 6JLm, the Au base will not be completely buried, the effect of improving the wear resistance due to the protruding primary crystal Si will be maintained, and the oil retention will be sufficient, so that the Au base will not be easily worn. In this way, in the first member, the primary Si crystals in the AJI-3i alloy constituting at least the sliding surface portion are in an arc shape, and the arc-shaped primary Si crystals are formed by etching the A intersection. Since it is a material that stands out in the range of 1 to 6 pm, it not only shows excellent abrasion resistance at room temperature like conventional sliding members, but also shows excellent wear resistance at 250°C.
It shows good wear resistance even in high temperature atmospheres,
It exhibits excellent wear resistance in high-temperature atmospheres ranging from room temperature to about 250°C. in this case,
In a high temperature atmosphere exceeding 250℃, All
The base becomes softer, and the protruding primary Si crystals tend to be buried in the AfL base, making it easier for the Au base itself to wear out. Furthermore, since this A-shaped base tends to soften, it tends to cause plastic flow during sliding, and it adheres to the second member, deteriorating its wear resistance. Next, in the sliding member according to the present invention, the second member which is a mating member of the first member is subjected to a composite dispersion plating treatment on at least the sliding surface portion thereof relative to the first member. be. In this case, the composite dispersion plating applied to the second member is, for example, (1) N1-P-3i3N, (electrolytic plating) containing 4.0 to 6.5% by weight of P in Ni plating, Si3N4 powder with an average particle size of 0.6 to 0.8 JLm is
Electrolytic plating using 30 area% dispersed material. (2) N1-P-Co-Si3 N4 (Electrolytic plating) Electrolytic plating using the above component (1) further containing 15 to 35% by weight of Co. is used. In such electrolytic plating, P has the effect of forming a Ni2P alloy phase through thermosetting treatment to improve the wear resistance of the plating layer, and Co has the effect of improving the wear resistance and heat resistance of the plating layer in a high-temperature atmosphere. It has the effect of further improving sex. In such electrolytic plating, the plating thickness is 40 to 2
00) Lm, the hardness of the plating layer is 800-10100
It is particularly desirable to set it to about OH. Furthermore, it is desirable that the degree of dispersion of Si3N4 be between 10 and 30 area%.If it is less than 10% by volume, the wear resistance of the plating layer itself tends to decrease, while if it is more than 30% by area, it will cause damage to the mating material. This is because it tends to reduce the wear resistance of a certain first member. The second member is made of a conductive material that can be plated, such as cast iron, carbon steel, spring steel, stainless steel, or aluminum alloy. (Function of the Invention) In the sliding member according to the present invention, at least the sliding surface of the first member with respect to the second member is made of a hypereutectic Al-3t alloy in which primary crystal Si, which contributes to improving wear resistance, is circular. It has an arc shape, and the arc-shaped primary crystal Si protrudes in a range of 1 to 6 ILm due to the etching of the All base, and at least the sliding surface of the second member relative to the first member is subjected to a composite dispersion plating treatment. Because of this, both the first member and the second member, which come into contact with each other and slide relative to each other, have a low amount of wear and have excellent wear resistance. This results in greatly improved durability. (Example) In this example, a case is shown in which the first member is a disk and the second member is a bottle. The first member, the disk, is made of #An-
AA standard - A390 widely used as Si alloy
It is made from an alloy, and the die casting material of this alloy is cut into the shape of a predetermined disc rough material, and the sliding surface with the second member, the bottle, is made using a porous GC grindstone. Surface grinding (semi-finishing) was carried out using an elastic grindstone, and the sliding surface was further finished using an elastic grindstone.As a result, the wear-resistant primary Si crystals on the sliding surface formed an arc shape.Next, The A-shaped base on the sliding surface is etched with a NaOH aqueous solution, and the arc-shaped primary crystal Sf is removed from the base surface by 4
pm Disk with a protruding sliding surface part (No.
1) , and arc-shaped primary Si crystals are located 6 from the base surface.
Disc with a sliding surface that protrudes 4m (No. 2)
was produced as the first member. In addition, this primary Si is 6
FIG. 4 shows the surface metal structure of the sliding surface portion that protrudes by μm. In addition, as the second member, a bottle (No. 1) was used, in which the surface of a bottle rough material made of JISSK5 was subjected to a composite dispersion plating treatment of N1-P-Go-Si3N4. In this case, electrolytic plating was performed using a plating material in which the amount of added P was 5% by weight, the amount of added CO was 20% by weight, and the amount of Si3N4 dispersed was 30% by area, and the thickness of the plating layer was 50 J.
Lm. A bottle (No. 1) having a plating layer having a hardness of 900 HmV was prepared. Furthermore, for comparison, the disk was made of A390 alloy, which has excellent wear resistance as described above, was cut into the specified disk shape, and the sliding surface was polished with a grindstone to remove the primary Si surface. After smoothing, N
A disk (No. 3) has a sliding surface part in which the primary Si is made to protrude 4 μm from the base surface by etching with an aOH aqueous solution, and a disk (No. 3) has a sliding surface part in which the primary Si is made to protrude by about 0.61 Lm from the An base without breaking the primary Si by grinding. A disk (No. 4) having a sliding surface portion with a rough surface was fabricated. In addition, as a second member for comparison, JIS S
A bottle (No. 2) made of K5 bottle material whose surface was subjected to hard chromium plating treatment was used. In this case, the thickness of the hard chrome plating layer is 200 pm, and the hardness is 750 HmV.
A bottle was made. Next, as a combination of each disk (No. 1 to 4) and bottle (No. 1, 2) shown in Table 1,
Each was attached to the bottle-disk type friction tester shown in FIG. 2, and a friction (wear) test was conducted under the conditions shown in Table 2. As shown in Fig. 2, the pin-disk type friction tester used at this time was designed to rotate the disk 1 in the direction of arrow A, simultaneously press the bottle 2 in the direction of arrow B, and apply a contact load to the friction test machine. It is something that makes you The results are shown in Table 1 and FIG. As shown in Table 1 and FIG. 1, Example 1 is a combination of a first member and a second member according to the present invention.
In case 2, although the temperature of the disk is as high as 250°C, the first member, the disk (No.
1, 2) and the second member pin (No.
In both cases 1), the amount of wear on each sliding surface portion was considerably small, and it was recognized that the durability was extremely excellent not only at room temperature but also in high-temperature atmospheres. In contrast, a disk with a smooth primary Si surface (N
o, 3) and a pin with composite dispersion plating (No. 1)
In the case of Comparative Example 1, which is a combination with
No. 4) and pins with composite dispersion plating (No.
In the case of Comparative Example 2, which is a combination with 1), it was observed that the amount of wear on the disk and pin was even greater than in Comparative Example 1. Furthermore, in the case of Comparative Example 3.4, which is a combination of a disk (No. 1.2) that satisfies the present invention and a hard chrome-plated pin (No. 2), the wear amount of the pin was The number of discs (No. 1, 2
) has increased compared to Example 1.2, and Comparative Example 5. is a combination of the comparative example disks (No. 03, 4) and the hard chrome-plated pin (No. 2). In the case of No. 6, it was observed that the amount of wear on the pin was even greater, and the amount of wear on the disk was also greater. Furthermore, considering the case where the configuration of the first member among the sliding members according to the present invention is applied to the bore portion of a cylinder block made of an aluminum alloy, the mating material of primary crystal Si protruding on the sliding surface portion In addition to wear caused by sliding,
In the acidic friction atmosphere caused by HC carbon (concentration of about 0.02% by weight) and HNO3 (concentration of about 0.005% by weight) contained in the combustion gas, wear may occur due to corrosion of the A-based base. However, when the structure of the first member according to the present invention is adopted, the amount of friction wear per unit time of the protruding primary Si and the unit of Au base Since the amount of corrosion wear per hour is about the same (approximately 0.07m/Hr in both cases), the protruding height of primary Si is the same as before sliding regardless of the sliding time. Therefore, even after long-term sliding, there was no significant deterioration in wear resistance due to corrosive wear, and therefore, even after long-term sliding, excellent wear resistance was exhibited.

【Effect of the invention】

In the sliding member according to the present invention, the sliding surface portion of the first member constituting the sliding member is free from surface cracking and falling off of primary crystal Si, which contributes to wear resistance in hypereutectic A-3i alloy. In addition, due to the etching of the Au base, the arc-shaped primary crystal Si protrudes in a range of 1 to 6 μm, and the sliding surface of the second member, which also constitutes the sliding member, is composite dispersion plated. Since the treatment is applied to the structure, both the first member and the second member have a significantly less amount of wear when sliding, and the wear of one member does not affect the other member. It is possible to eliminate wear, and by combining the specified first member and second member, it is possible to reduce the amount of wear on both itself and the mating member, and it has excellent durability. This provides an extremely excellent effect of being a sliding member.

[Brief explanation of the drawing]

Figure 1 is a graph showing the results of high temperature friction tests, Figure 2 is a graph showing the results of high temperature friction tests.
The figure is an explanatory diagram showing the outline of the pin-disk type friction test, and Figure 3 is an enlarged photograph (400x) of the surface metallographic structure showing an enlarged sliding surface area with protruding primary Si crystals produced by conventional grinding.
, FIG. 4 shows an arc-shaped primary Si crystal in an embodiment of the present invention.
This is an enlarged photograph (400x) of the surface metallographic structure showing a sliding surface portion that protruded by 6 JLm. 1... First member (disk), 2... Second member (bin).

Claims (1)

[Claims] (1) In a sliding member having a first member and a second member that are in contact with each other and slide relative to each other, at least the sliding surface portion of the first member relative to the second member is made of hypereutectic Al. - In the Si alloy, the primary crystal Si that contributes to wear resistance forms an arc shape without causing surface cracks or falling off, and the etching of the Al base causes the primary crystal Si to become 1
A sliding member, characterized in that the sliding member protrudes in a range of ~6 μm, and at least a sliding surface portion of the second member relative to the first member is subjected to a composite dispersion plating treatment.