JPH05203057A - Sliding member - Google Patents

Abstract

PURPOSE:To provide a sliding member having excellent wearing resistance and a counter part attacking property under a severe condition of high temperature, high load, etc. CONSTITUTION:In a sliding member, on at least a sliding surface, plating is applied with a nickel group alloy plating film containing 0.1 to 10.0wt.% boron and further containing 10 to 80wt.% tungsten or 5.0 to 70.0wt.% molybdenum. In this sliding member, excellent wearing resistance and a counter part attacking property are provided under a severe condition of high temperature, high load, etc., to obtain a good result even in the case of use for an engine of using high lead gasoline and an engine of high output and high load.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a sliding member having a nickel-base alloy plating layer formed on a sliding surface,
More specifically, the present invention relates to a sliding member in which a nickel-based alloy plating film containing boron and containing tungsten or molybdenum is formed on a sliding surface.

[0002]

2. Description of the Related Art A sliding member such as a piston ring for an internal combustion engine, which is subjected to high temperature and high load, is often provided with hard chrome plating on its sliding surface in order to improve wear resistance. However, the chrome plating not only requires a long time for the treatment, but also requires a large amount of treatment for the waste plating solution in order to prevent environmental pollution, resulting in an increase in the cost required for the plating. In addition, the use of chrome-plated sliding members in the components of high-lead gasoline engines and high-power, high-load engines may cause problems in terms of wear resistance, corrosion resistance, seizure resistance, etc. there were.

As a method for solving this problem, Japanese Patent Publication No. 56-18080 proposes a composite plating in which hard particles such as nitrides, carbides and oxides are dispersed in a Ni-P alloy matrix. According to this known plating, it is possible to form a film excellent in wear resistance, seizure resistance, and corrosion resistance to some extent by appropriately selecting the type, size, and amount of dispersed hard particles. It is used for sliding members such as cylinder liners and piston rings.

[0004]

However, the Ni-P alloy matrix in the composite nickel alloy plating in which the above hard particles are dispersed becomes brittle when subjected to high heat and high load, and is operated at high speed under severe conditions. When it is used as a sliding member of an engine, the wear resistance, seizure resistance, corrosion resistance, etc. are not always satisfactory.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a sliding member having a film having excellent wear resistance, seizure resistance, and particularly corrosion resistance formed on the sliding surface. ..

[0006]

In order to achieve the above object, the present invention contains 0.1 to 10.0% by weight of boron, and 10 to 80% by weight of tungsten or 5.0.
The present invention provides a sliding member in which a nickel-based alloy plating film containing molybdenum of 70.0 wt% is plated on at least the sliding surface.

Further, in the present invention, in the nickel-base alloy plating film, one kind or a combination of two or more kinds selected from hard particles such as oxides, carbides and nitrides having a particle size of 10 μm or less and solid lubricating particles is used. It also provides a sliding member dispersed in a proportion of 5 to 30% by volume.

[0008] In addition, the present invention provides a sliding member having a hardness of HV 800 or more by heat-treating the above nickel-base alloy plating film.

[0009]

Since the sliding member according to the present invention contains boron and tungsten or molybdenum on its sliding surface and has a nickel-base alloy plating film having excellent wear resistance, corrosion resistance and seizure resistance, high lead gasoline is used. Good results can be obtained even when used in an engine or a high-power, high-load engine.

[0010]

The present invention will be described in detail below with reference to sliding members according to the embodiments of the present invention.

An example of the use of the steel material used as the base material of the sliding member of this embodiment is 0.16 to 1.30.
% Steel, a steel material containing 12 to 19% of chromium, or a steel material containing molybdenum and vanadium. The sliding member of this example is a nickel-based alloy plating film having excellent wear resistance, seizure resistance, corrosion resistance, heat resistance, etc. on the peripheral sliding surface of the sliding member composed of the above-mentioned base material. Is formed.

Here, the nickel-base alloy plating film contains 0.1 to 10.0% by weight of boron (B), and
10-80% by weight of tungsten (W) or 5.0
A plating film made of a nickel-based alloy containing molybdenum (Mo) in an amount of ˜70.0% by weight.

Boron (B) in matrix of nickel-based alloy
Addition improves the corrosion resistance, seizure resistance, and wear resistance of the plating film, but the addition of tungsten (W) or molybdenum (Mo) further strengthens the toughness of the matrix and further improves the heat resistance and corrosion resistance of the plating layer. improves. As a result, it is possible to significantly improve various characteristics such as wear resistance, seizure resistance, and corrosion resistance of sliding members such as sliding members.

In order to obtain the effect of improving the wear resistance and the like by adding the above boron (B), the boron (B) should be at least 0.1.
It is necessary to contain it by weight%. On the other hand, if the content of boron (B) exceeds 10.0% by weight, the plating film becomes brittle.

The effect of adding tungsten (W) and molybdenum (Mo) is closely related to the content of boron (B) in the plating film. For example, when the boron content is high, tungsten (W) or molybdenum (Mo) is used.
Sufficient hardness and the like can be obtained even if the content is 0.1%. On the other hand, when the content of boron is low, the heat resistance of tungsten (W) is 80% by weight, and that of molybdenum (Mo) is up to 70% by weight with the addition of tungsten (W) or molybdenum (Mo). It is possible to improve the corrosion resistance, seizure resistance, and corrosion resistance.

[0016] The ratio of boron to tungsten (W) or molybdenum (Mo) determines how much wear resistance, seizure resistance, heat resistance, and corrosion resistance are required for the sliding member, or what the mating material is. It is appropriately selected according to various conditions such as whether it is a proper material.

Hard particles such as metal nitrides, metal carbides and metal oxides having a particle size of 10 μm or less (eg Si ₃ N ₄ ,
SiC, WC, Al ₂ O ₃ , ZrO ₂ , Cr ₂ O _3, etc.) or one or more selected from solid lubricant particles (for example, BN (boron nitride), polytetrafluoroethylene, etc.) You may combine and it may be made to contain in the said nickel base alloy plating film.

By incorporating these hard particles, seizure resistance and wear resistance can be improved. Also,
Friction can be reduced by incorporating solid lubricant particles. In this case, the content ratio of these hard particles is 5.0
If it is less than 30% by volume, the above effect cannot be obtained, and if it is more than 30% by volume, the density of the plating film itself decreases and becomes brittle, which is a problem in use.

Further, the finer the particle size of these hard particles and solid lubricant particles, the higher the effect of adding these particles. On the other hand, when the thickness is 10 μm or more, the attacking property against the other party becomes strong, the particles fall off, and the wear resistance of the plating film is impaired. The finer the particle size of a particle, the more expensive it is. Therefore, the particle size of the particle is appropriately selected within the above range in consideration of the price and the use situation. Preferably 0.3 μm to 5 μm
It is better to use one within the range. The addition amount of the hard particles or the solid lubricant particles is also appropriately selected within the above range in consideration of the purpose and the like.

Further, the above nickel-base alloy plating film,
Alternatively, when a plating film containing hard particles, solid lubricant particles, etc. is subjected to a heat treatment, a boron compound is produced to increase the hardness. The rate of increase in hardness depends on the processing temperature. For example, a nickel (Ni) -tungsten (W) -boron (B) plating film has a hardness of 650 Hv in the as-plated state, but when heat-treated at 580 ° C. for 1 hour, the hardness becomes 1150 Hv. Further, the nickel (Ni) -molybdenum (Mo) -boron (B) plating film has a hardness of 550 in the as-plated state.
Although it is Hv, the hardness becomes 1100 Hv by performing heat treatment at 580 ° C. for 1 hour.

As described above, the hardness of the nickel-base alloy plating film can be changed within a certain range depending on the heat treatment temperature, so that the heat treatment temperature can be changed to obtain the hardness suitable for the use condition.

The thickness of the nickel-base alloy plating film of the present invention is about 5 μm to 250 μm, and the thickness is selected according to the material, surface treatment, etc. of the outer peripheral sliding surface of the sliding member.

The plating solution and plating conditions for producing the sliding member coated with the nickel alloy film of nickel (Ni) -tungsten (W) -boron (B) according to the present invention are shown below. Plating solution composition Plating condition Silicon nitride (Si ₃ N ₄ ; 0.5 μm): 15
0 g / l sodium tungstate _{(Na 2 WO 4 · 2H 2} O):
60 g / liter diammonium citrate (NH ₄ C ₆ H ₆ O ₇ ): 60 g /
L nickel sulfate _{(Ni 2 SO 4 · 2H 2} O): 20g / l trimethylamine borane _{((CH 3) 3 NBH 3} ): 3g
/ Liter Current density: 3.0 A / dm ² Liquid temperature: 55 ° C

Next, the plating solution and plating conditions for producing the sliding member coated with the nickel alloy film of nickel (Ni) -molybdenum (Mo) -boron (B) according to the present invention are shown below. Plating solution composition Plating conditions Silicon nitride (Si ₃ N ₄ ; 0.5 μm): 15
0 g / liter sodium molybdate (Na ₂ MoO ₄ · 2H ₂ O):
60 g / liter diammonium citrate (NH ₄ C ₆ H ₆ O ₇ ): 60 g /
L nickel sulfate _{(Ni 2 SO 4 · 2H 2} O): 20g / l trimethylamine borane _{((CH 3) 3 NBH 3} ): 3g
/ Liter Current density: 3.0 A / dm ² Liquid temperature: 55 ° C

Next, the wear resistance of the sliding member according to the present invention,
The test results regarding opponent aggression are shown.

Silicon nitride (Si
₃ N ₄ ) -dispersed Ni-P alloy plating film on the sliding member is comparative sample A, and the sliding surface is silicon nitride (Si
₃ N ₄ ) -dispersed nickel (Ni) -tungsten (W) -boron (B) alloy plating film was used as a sliding member for sample B (Ni-49.1 wt% W-3.0 wt%
B), a sample B was heat treated at 580 ° C. for 1 hour to increase hardness, and a sample C was used as a sliding member, and a silicon nitride (S
i ₃ N ₄₎ nickel was dispersed (Ni) - molybdenum (Mo) - boron (Sample D (Ni-29.0 wt% Mo-2.8 wt sliding member subjected to alloy plating film B) % B), and sample D is heat-treated at 580 ° C. for 1 hour to obtain a sliding member having an increased hardness as sample E. Here, samples B to E are the sliding members of the present invention.

For the wear resistance and opponent attack test, an Amsler type wear tester was used, and almost half of the rotating piece was immersed in oil.
It was carried out by a method of contacting with a fixed piece (sample) and applying a load. The test conditions are as follows.

(Test Conditions for Abrasion Resistance and Opponent Aggression Test) Counterpart material: FC25 (HRB98) Lubricating oil: 10W30 Oil temperature: Room temperature Friction speed: 0.89 m / sec (500 rpm) Load: 60 Kg Time: 20 hours Abrasion amount measurement: Abrasion amount (μm) was measured with a step profile using a roughness meter.

The test results are shown in FIG. The samples B to E according to the invention of the present application have higher wear resistance than the comparative sample A,
It can be seen that the opponent's aggressiveness is also good. Further, it is apparent that even the sliding member according to the present invention, which is subjected to heat treatment, has better wear resistance and opponent attacking property than those which are not subjected to heat treatment.

[0030]

The sliding member according to the present invention contains boron and tungsten or molybdenum on its sliding surface and has a nickel-base alloy plating film excellent in wear resistance, corrosion resistance and seizure resistance. Good results can be obtained even when used in an engine to be used or a high-power, high-load engine.

[Brief description of drawings]

FIG. 1 is a graph showing test results regarding wear resistance and opponent attack of a sliding member of the present invention.

[Explanation of symbols]

A A comparative sample in abrasion resistance and opponent attack test B Sample with Ni-WB alloy plating film in which silicon nitride is dispersed C Sample B with heat treatment at 580 ° C. for 1 hour D Silicon nitride Dispersed Ni-Mo-B
Sample E coated with the above alloy plating film E Sample D heat-treated at 580 ° C. for 1 hour

Claims (3)

[Claims] 1. A nickel-base alloy plating film containing 0.1 to 10.0% by weight of boron and 10 to 80% by weight of tungsten or 5.0 to 70.0% by weight of molybdenum. A sliding member having at least a sliding surface plated. 2. A particle selected from hard particles such as oxides, carbides and nitrides having a particle size of 10 μm or less and solid lubricating particles.
The sliding member according to claim 1, wherein one kind or a combination of two or more kinds is dispersed in the nickel-based alloy plating film at a ratio of 5 to 30% by volume. 3. The sliding member according to claim 1, wherein the nickel-base alloy plating film is heat-treated to have a hardness of HV 800 or more.