JPH0559200B2 - - Google Patents

Description

[Detailed description of the invention]

(a) Industrial application field This invention is applicable to automobiles, ships, various electric machines, OA
Plate film (overlay alloy) used as the surface layer of sliding parts and plain bearings of equipment, agricultural machinery, machine tools, food machinery, and other general industrial machinery.
The present invention relates to a method for manufacturing a sliding component and a plain bearing. (b) Conventional technology As a conventional technology, "Bearing Lubrication Handbook" June 1963
March 30th, published by Nikkan Kogyo Shimbun, pages 415, 432, and 433, a composite plating layer is provided by two-step electroplating layer, and this is diffused by heat treatment to create an alloy for the surface layer. The technique is shown. In addition, in Japanese Patent Publication No. 57-9635, alloys for Pb-Sn-Sb-In surface layers or alloys for Pb-Sn-Sb-Tl surface layers were prepared by two-step electroplating and heating diffusion.
A technique for providing is shown. Also, special public service in 1977-
In No. 22498, a copper alloy layer provided on a steel back metal is coated with molten lead indium, copper is diffused into the lead indium layer, and the back metal, copper-lead alloy layer, and lead-indium-copper surface layer are formed. A technique for making a sliding material is shown. (c) Problems to be solved by the invention In recent years, internal combustion engines for automobiles and other general industrial machinery have been making rapid progress, and there is a trend toward higher speeds and heavier loads, and the sliding For bearings and sliding materials, the life of the conventional surface layer alloys mentioned above has been shortened due to lack of lubricating oil film, especially under high-speed and high-load conditions, due to poor wear resistance, fatigue resistance, and corrosion resistance. Furthermore, sliding bearings are prone to so-called cavitation erosion, which erodes the surface layer of the sliding bearing in lubricating oil, and it is necessary to reduce and prevent this type of damage. It's here. Conventional Pb-Sn alloys, Pb-In alloys, and Pb-Sn-In alloys for surface layers have too large cavitation erosion, which is undesirable. There has been a strong demand from various industries to reduce and prevent cavitation erosion. In addition, the sliding material manufactured by the manufacturing method shown in Japanese Patent Publication No. 39-22498 is produced by joining molten lead-indium alloy with a copper alloy layer by casting, and then diffusing this copper alloy layer into the lead-indium alloy. An indium-copper surface layer was created.
For this reason, in Japanese Patent Publication No. 39-22498, it is necessary to heat the composite material to a very high temperature (650°C in the example of Japanese Patent Publication No. 39-22498) in order to diffuse copper, which has a high melting point, into the lead-indium alloy. It was necessary.
When heated to this high temperature, unevenness occurs on the surface of the copper-lead alloy layer (deformation of the surface of the copper-lead alloy layer) due to the temperature difference between copper and lead. It is impossible to obtain a surface layer (with a thickness of several micrometers), and as a result, there are disadvantages such as variations in bearing characteristics and poor reliability. The inventor of the present invention is Japanese Patent Application No. 60-109627
No. 266544), the Pb-Cu-In surface layer alloy or the Pb-Cu-In-Sn surface layer alloy was shown to be effective in solving these problems.
The scope of claims of this patent application 1986-109627 is that Pb
-The manufacturing method of Cu-In alloy was not specified. (d) Means for Solving the Problems The object of the present invention is to provide a surface layer for flat bearings and sliding materials under high speed and high loads, as well as for underwater or lubricating oil for sliding bearings. Pb can reduce cavitation erosion and can be used by resisting wear, fatigue, and corrosion caused by lubricating oil.
- To obtain a method for manufacturing sliding parts and plain bearings having a Cu-In or Pb-Cu-In-Sn plating film (surface layer). Plated film (surface layer) related to the method of the present invention
is Cu0.1~6%, In1~10% and the balance by weight.
Consists of Pb and unavoidable impurities. Other surface layer alloys relevant to the method of the invention include Cu0.1 to
6%, In 1 to 10%, Sn 8% or less, and the balance consists of Pb and inevitable impurities. The method of manufacturing sliding parts and plain bearings having a plating film (surface layer) of the present invention is to directly plate a copper-lead alloy with a steel back metal or to plate the Pb-
A Cu alloy is electroplated, and then In or In is electroplated on this Pb-Cu alloy plating layer, and then Sn or an In-Sn alloy is electroplated on top of the Pb-Cu alloy plating layer, and the two layers formed by these electroplatings are Alternatively, a composite plating layer consisting of three layers is heat-treated to cause mutual diffusion of the components of the composite plating layer, thereby causing Pb-Cu-
It is characterized by producing an alloy for an In surface layer or an alloy for a Pb-Cu-In-Sn surface layer. (E) Effect The Ni plating layer provided on the copper-lead alloy with the steel backing is effective in preventing the components of the plating film (surface layer) from diffusing into the copper-lead alloy with the steel backing. . (1) Pb-Cu for making plating film (surface layer)
The thickness of the alloy plating layer is in the range of 5 to 100 μm,
(2) The thickness of the In, In and Sn, or In-Sn alloy plating layer is in the range of 1 to 20 μm, and the total thickness of the so-called composite plating layer, which includes the above (1) and (2), is 6 μm.
It is in the range of ~129μm. Diffusion heat treatment of this composite plating layer is performed at a temperature range of 80 to 180°C for 10 minutes to 20 hours. (f) Examples Examples of the present invention will be described below. Pb-Cu alloy plating liquid composition shown in the table below on copper-lead alloy with steel backing plated directly or on top of Ni plating.
Pb and Cu alloy plating was applied under the plating conditions,
Next, In plating or In and Sn plating, that is, In plating and then Sn plating on top of that, or In-
Sn alloy plating (previously known and publicly used plating liquids, such as "Bearing Lubrication Handbook", Nikkan Kogyo Shimbun, June 1963)
(Pages 367 to 368, pages 432 to 438, published on March 30), and then diffused through heat treatment to form an alloy. Manufactured bearings.

【table】

[Table] In conventional Pb-Sn alloy electroplating, as the plating thickness increases, the roughness of the plating surface becomes rougher. Furthermore, conventional Pb-Sn-Cu alloy electroplating tends to cause the plating to become rough. Furthermore, Pb-Sn alloy electroplating and Pb-Sn-Cu alloy electroplating tend to change the surface condition and electrodeposited components due to variations in additives. Conventional Pb-Sn alloy electroplating and
Sn ⁺² is used in the plating liquid for Pb-Sn-Cu alloy electroplating.
This Sn ⁺² is oxidized to Sn +4, which is not deposited, by dissolved oxygen and Cu ⁺² in the plating solution, and when this Sn ⁺⁴ becomes excessive, the plating solution becomes cloudy and separates ^. , there is a risk of embrittling the electrodeposited material. Furthermore, if Cu ⁺² is present in the plating solution, the change from Sn ⁺² to Sn ⁺⁴ will be accelerated, making the plating solution unstable, and the plating solution will need to be separated by precipitation or ^the plating solution should be renewed. There was a problem in that it was not possible to continue the plating work. In the plating process in this example, the plating liquid is an extremely stable alloy plating liquid of Pb and Cu, so it
Compared to Pb-Sn plating and Pb-Sn-Cu plating,
It was possible to use it continuously for an extremely long time. Continuous plating was also possible while filtering with activated carbon to remove dust adhering to the plating jig and the object to be processed, as well as impurities in the plating solution. Furthermore, in the plating treatment of this example, a dense plating (surface layer) with specular gloss was obtained. For example, even when the base surface roughness was 3 to 5 μm higher, leveling was good, and after plating was completed, a surface with a surface roughness of about 0.1 to 0.8 μm was obtained. Table 1 compares the composition, mechanical properties, corrosion loss, and thickness of the reaction layer with the base alloy of various bearing surface layer alloys manufactured using the method of the present invention with bearing surface layer alloys manufactured using the conventional technology. It was shown. As is clear from Table 1, the surface layer alloy provided by the method of the present invention has higher hardness and tensile strength than the conventional surface layer alloy, and can withstand high loads. When Cu reaches 5%, elongation decreases. Therefore, Cu of 6% or more becomes brittle. In addition, looking at the corrosion loss with degraded oil, with the exception of Pb-Sn-In alloys without a Ni barrier, Sn or In diffuses into the base, and as a result, the corrosion loss at 165°C
After heat treatment for 1000 hours, the sample was significantly corrosive due to degraded oil. In contrast, the surface layer alloy provided by the method of the present invention has extremely high corrosion resistance, about 1/4 to 1/6 of that of conventional alloys. In particular, Pb-Cu-In-Sn is extremely good. The copper base alloy and the In and In alloys used in the method of the present invention
The thickness of the reaction layer of Sn is thin and good, but if the amount of Sn is excessive, the reaction layer becomes thick. If the thickness of this reaction layer exceeds 3 microns, it has the disadvantage of becoming gradually brittle and prone to fatigue. The reason for the increase in corrosion resistance is thought to be that the addition of Cu reduces the diffusion of In into the base alloy, as shown in Figure 1. When a Ni barrier is provided between the surface layer alloy and the base alloy, corrosion loss is extremely small and corrosion resistance is good. Even when there is no Ni barrier, by containing a predetermined amount of Cu, the residual rate of In in the surface layer increases and corrosion resistance that can be used practically can be obtained.

[Table] Next, a seizure test using a Suzuki tester and the amount of wear were investigated. The test conditions were as follows, and the shape and sample condition of the test piece 1 were as shown in FIGS. 2 to 4. Material of shaft 2: S450 Lubricating oil: SAE30#, applied 0.02ml during assembly Shaft rotation speed: 780r.pm Test piece: Outer diameter 27.2mmφ, inner diameter 22mmφ, depth 1mm
The base material is a Cu75%-Pb25%G copper alloy with a steel backing metal.The total thickness of the steel backing metal and copper alloy layer is 1.5mm, and a 10μm thick surface layer alloy is coated by electroplating. Established. Test time: 70 min. Table 2 shows the average values of seizure load and wear thickness under the condition of lubrication with one drop (0.02 ml) of oil applied only during assembly. The surface layer alloy according to the method of the present invention has a high seizure load and a small wear thickness.

[Table] Next, the fatigue resistance of the surface layer alloy provided by the method of the present invention was investigated by a bearing fatigue test using a Saphire tester. The test conditions are as follows. Shaft material: S55C, shaft shape 53mmφ Test bearing: Sintered copper-lead alloy with steel backing (Cu75%)
-Pb25%) and plated with various surface layer alloys shown in Table 3 to a thickness of 15 μm, test bearing outer diameter = 56.0 mm,
Test bearing wall thickness = 1.5mm, test bearing width =
26.0mm. Lubricating oil type and temperature: SAE20#, 90℃ Rotation speed: 3250r.pm Test time: 20 hours, Test load: 1330Kg/cm ²

[Table] As is clear from Table 3, the alloy produced by the method of the present invention is good with no fatigue cracks, Pb-5%Cu-
The reason why a small area was observed in 6%In-1%Sn was due to a part of the underlying alloy being destroyed. Next, the plating film (surface layer) related to the method of the present invention
The engine test was repeated three times. The test conditions are as follows. Test machine used: Motorcycle engine 35 horsepower Shaft rotation speed: 13000r.pm Shaft diameter: 33mm Shaft material: S50C Test time: 10 hours Lubricating oil: SAE20# Lubricating oil temperature: 145-150℃ Test load: Full load Test bearing: outer diameter 36.0mm, wall thickness 1.5mm, width 13.8mm,
After plating the plating film (surface layer) shown in Table 4 on the bearing (copper-lead sintered alloy with steel backing (Cu-75%-Pb25%)) with a Ni barrier,
A thickness of 15 μm was provided. As shown in Table 4, the alloy produced by the plating film (surface layer) preparation method of the present invention showed no cracks and was found to be extremely resistant to fatigue.

[Table] Also, plating film (surface layer) and base metal (Ni)
As is clear from Table 5, the method for producing the plating film (surface layer) of the present invention is superior in terms of adhesive strength. Further, to describe in detail the properties of the plating film (surface layer) related to the method of the present invention, as shown in Table 5, there is comparative data on heat treatment conditions and adhesive strength. This comparative data was obtained using the method shown in British Patent No. 2,121,547 and US Patent No. 4,501,154. is strong, with little difference due to heat treatment temperature, and is almost stable up to 165℃ Pb−
9%Sn-9%In) fluctuates downward. From this point of view, plating film (surface layer) (Pb-Cu-In alloy and Pb-Cu-In-Sn alloy) by the method of the present invention
I can see that it is excellent. In addition, in a comparative test of surface layer roughness, the surface roughness of the conventional surface layer alloy was 2 to 7μ compared to the surface roughness of the base metal of 0.5 to 3μ (Ni), whereas this The surface roughness of the plating film (surface layer) obtained by the method of the invention was 0.6μ, which is smaller than that.
In other words, the surface roughness was 1/3 to 1/11 that of conventional products, so the appearance was smooth. The method of the present invention has the following advantages. In other words, (1) the plating solution is an extremely stable Pb and Cu alloy plating solution, so it cannot be used in conventional Pb-Sn or Pb-Sn-
Easy to use continuously compared to Cu plating. Also,
Continuous plating is possible while performing activated carbon filtration. (2)
You can always get a detailed plating with a mirror shine. For example, leveling is good even when the base surface is 3 to 5μ,
After plating is completed, it becomes 0.1 to 0.8μ, which is extremely good. *P10/Ni/KS25 indicates that it consists of a steel layer + Kelmt sintered layer + Hi plating layer + Sn10%-Pb plating layer. In other words, the inner surface of semicircular KS25 is plated with Ni, and
Bearing with P10 plating. Kelmt is
Bronze containing 25% Pb. **P9 indicates an In9%-Sn10%-Pb alloy plating layer. *** In5 indicates that In is 5wt%. ＊＊＊＊ P8 indicates a Sn8%-Cu3%-Pb alloy plating layer. Next, cavitation tests on the surface layers of various alloy materials were conducted under the following conditions. In other words, (a)
Sample: 1.5μm Ni plating was applied on KS25 measuring 50mm vertically x 50mm horizontally x 1.5mm thick, and then
18μm −5%In, Pb−10%Sn, Pb−10%Sn−
9%In, Pb−10%Sn−2.5%Cu, Pb−2.5%Cu−
I plated 6% In. (b) Ultrasonic output: 19KHz,
At 600W, the diameter of the horn tip is 35mm, that is, the energy density is 62.4W/cm ² at 19KHz. (c) Impact conditions: An ultrasonic horn was placed with a clearance of 0.5 mm to the sample in water at a temperature of 15 to 20°C, and the test was conducted for 1 minute. The test results are shown in Table 6.

[Table] As shown in Table 6, Cu, Sn, and In have the effect of suppressing the cavitation erosion of Pb, but among them, Cu is most effective in strengthening Pb. (g) Effects of the invention In the method for producing a plating film (surface layer) of the present invention,
Since the plating liquid for the Pb--Cu alloy plating layer is extremely stable, it has become possible to use it continuously, making it possible to carry out the method of the present invention continuously. In addition, as is clear from the results shown in the examples, it is now possible to obtain an alloy with excellent properties as a surface layer for sliding parts or plain bearings, and
Cavitation erosion is significantly reduced compared to Pb-Sn alloy, Pb-In alloy and Pb-Sn-In alloy, and Pb-Sn-Cu for the conventional surface layer.
The cavitation erosion was reduced to the same level as that of the alloy, and the intended purpose of the present invention could be achieved.

[Brief explanation of the drawing]

Figure 1 is a front view of the test piece used in the seizure test, Figure 2 is a sectional view taken along the - line in Figure 1, and Figure 3 is a sectional view showing the test conditions of the seizure test. 4 is a schematic diagram showing the state of cavitation erosion test. 1 shows a test piece for the seizure test.

Claims (1)

[Scope of Claims] 1. A sliding plate that is used as a surface layer of sliding parts, flat bearings, etc. and has a plating film consisting of 0.1 to 6% Cu, 1 to 10% In, and the balance being Pb and unavoidable impurities. A method for manufacturing dynamic parts and plain bearings, which includes the steps of: providing a Pb-Cu alloy plating layer by electroplating; and providing an In plating layer on the Pb-Cu alloy plating layer by electroplating, thereby a step of creating a composite plating layer consisting of two layers; heat-treating the composite plating layer at a temperature range of 80 to 180°C to diffuse the constituent components of the composite plating layer;
and thereby forming a plating film. 2 The Pb-Cu alloy plating layer contains 60 to 150 g of lead borofluoride, 1.0 to 5.0 g of copper borofluoride, and 20 to 150 g of lead borofluoride.
In a Pb-Cu alloy plating liquid containing 120 g/of borofluoric acid, 0 to 35 g/of boric acid, and 1 to 6 g/of one or more additives of resorcinol, hydroquinone, and catechol, The temperature of the plating solution is 15-45℃, and the cathode current density is 1.0-45℃.
6.0 A/dm ² and a current density of 0.5 to 5.0 A/dm ² at an anode made of lead, and electroplating is performed while stirring the plating solution.
A manufacturing method according to claim 1. 3 Used as a surface layer for sliding parts and plain bearings, with a weight of 0.1 to 6% Cu, 1 to 10% In, and 8% Sn.
A method for manufacturing sliding parts and plain bearings having a plating film consisting of Pb and unavoidable impurities. On this Pb-Cu alloy plating layer, an In-Sn alloy plating layer is provided, thereby creating a two-layer composite plating layer, and this composite plating layer is heat-treated in a temperature range of 80 to 180℃. , the above manufacturing method of diffusing the constituent components of the composite plating layer, thereby creating an alloy for the surface layer. 2 The Pb-Cu alloy plating layer contains 60 to 150 g of lead borofluoride, 1.0 to 5.0 g of copper borofluoride, and 20 to 150 g of lead borofluoride.
In a Pb-Cu alloy plating liquid containing 120 g/of borofluoric acid, 0 to 35 g/of boric acid, and 1 to 6 g/of one or more additives of resorcinol, hydroquinone, and catechol, The temperature of the plating solution is 15-45℃, and the cathode current density is 1.0-45℃.
6.0 A/dm ² and a current density of 0.5 to 5.0 A/dm ² at an anode made of lead, and electroplating is performed while stirring the plating solution.
Manufacturing method according to claim 3.