JP2017186667A - Plating treatment material and slide member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a plating treatment material excellent in toughness; and to provide a slide member subjected to the plating treatment.SOLUTION: A plating treatment material 1 uses as a substrate 30, aluminum provided with at least 2-layered plating layer. The 2-layered plating layer has a base plating layer 21 and a surface plating layer 22, and the base plating layer 21 comprises an amorphous Ni plating layer having a film thickness of 4 μm or more, and the surface plating layer 22 comprises a Ni-P-based crystalline plating layer having a film thickness of 10 μm or more.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a plating material whose surface is plated and a sliding member which is plated.

  In recent years, in transportation equipment such as automobiles and railways, weight reduction and corrosion resistance have been demanded, but it has been easy to meet these performances by using aluminum as the material. However, since the wear resistance and the toughness are further required for a portion where a load or impact is applied such as a sliding member, it is indispensable to add characteristics by a surface treatment technique.

JP2015-129543A JP 2007-023316 A JP 2006-104536 A

  In the torque fluctuation absorbing damper described in Patent Document 1, the torque fluctuation absorbing damper made of aluminum or an aluminum alloy is subjected to hard alumite treatment or hard chrome plating treatment in order to improve wear resistance and corrosion resistance. However, while the anodized film can obtain a hardness higher than that of the base aluminum, the alumite film is insufficient in stretchability. There was a problem that peeling occurred. As for chromium plating, there has been a problem that the use of hexavalent chromium is being restricted due to the influence of environmental regulations such as the recent RoHS directive.

  In addition, the wear-resistant member and the power transmission component described in Patent Document 2 disclose a wear-resistant member provided with a crystalline Ni-P plating film in order to improve the wear resistance. Since the surface plating layer has a crystal structure, high hardness can be obtained, but as time passes, the base material comes into contact with the outside air due to the generation and progression of micropores in the plating layer, which causes corrosion. There was a problem that it was easy.

  Furthermore, in the sleeve described in Patent Document 3, the surface hardness of the plating layer formed on the split sleeve is ensured to improve the wear resistance, and at the same time, the surface of the plating layer can be used even when the split sleeve is used for a long period of time. The weather resistance is improved so that no discoloration occurs. However, since the thickness of the plating layer is thin, sufficient toughness cannot be obtained. For example, when an impact is applied to the surface, there is a problem that peeling or cracking of the plating layer is caused in a wide region.

  An object of an aspect of the present invention is to provide a plated material excellent in toughness and a sliding member that is plated.

  A plating material according to an aspect of the present invention is an aluminum-based plating material provided with at least two plating layers, and the two plating layers include a base plating layer, a surface plating layer, and a surface plating layer. The under plating layer is made of an amorphous Ni plating layer having a thickness of 4 μm or more, and the surface plating layer is made of a Ni—P crystalline plating layer having a thickness of 10 μm or more.

  As one aspect of the present invention, it is preferable that the base plating layer is a Ni-P plating layer containing 10 mass% or more and 13 mass% or less of P.

  As one aspect of the present invention, the surface plating layer is preferably an electroless plating layer in which the peak half-value width of the position of the Ni (200) plane in the X-ray analysis pattern is in the range of 0.3 to 1 °.

  As one aspect of the present invention, the surface plating layer preferably has a Vickers hardness of 500 or more.

  As one aspect of the present invention, an intermediate plating layer composed of at least one of high sulfur content Ni plating having a film thickness of 1 μm or more and 3 μm or less or Ni—P plating is provided between the base plating layer and the surface plating layer. It is preferable to be provided.

  As one aspect of the present invention, on the surface plating layer, a plating layer composed of at least one of black trivalent Cr plating or black non-chromium alloy plating having a thickness of 100 nm to 400 nm is provided. Is preferred.

  As one aspect of the present invention, the above-described plating material is used as a sliding member, and has a sliding surface having the base plating layer and the surface plating layer.

  According to the aspect which concerns on this invention, the sliding member excellent in toughness and the sliding member by which the plating process was carried out can be provided.

FIG. 1 is an example of a plating material according to the present embodiment. FIG. 2 is an example of a laminated structure of plating according to this embodiment. FIG. 3 shows a first modification of the laminated structure of plating according to this embodiment. FIG. 4 shows a second modification of the laminated structure of plating according to this embodiment. FIG. 5 is an explanatory diagram for explaining the marking fracture area of Example 1 and the marking damage area of Comparative Example 2.

  Hereinafter, embodiments according to the present invention will be described with reference to the drawings, but the present invention is not limited thereto. The components of the embodiments described below can be combined as appropriate. Some components may not be used. In addition, constituent elements in the embodiments described below include those that can be easily assumed by those skilled in the art, those that are substantially the same, and those in a so-called equivalent range.

[Sliding member]
FIG. 1 is an example of a plating material according to the present embodiment. A transmission having a chain 2 attached thereto is used for a vehicle such as a motorcycle or a bicycle, or an industrial device such as a robot. The transmission includes a derailleur having the plating material 1.

  The plating material 1 is pressed against the chain 2 to become a chain guide, and the chain 2 moves from the track 3a having a different radius from the center AX of the transmission gear to the track 3b, and the gear of the transmission is changed.

  Thus, the plating treatment material 1 is a sliding member provided with the sliding surface 11 on which the chain 2 slides. The sliding surface 11 needs to have not only corrosion resistance and wear resistance but also toughness that can withstand the collision of the chain 2. Therefore, in order to have the toughness with which the plating material 1 can withstand the collision of the chain 2, the sliding surface 11 is at least plated in the present embodiment.

  FIG. 2 is an example of a laminated structure of plating according to this embodiment. The base material 30 of the plating treatment material 1 is a material whose strength is lower than that of steel, such as aluminum, copper, titanium, or magnesium. For example, the base material 30 is formed of aluminum (Al) or an aluminum (Al) alloy. Thereby, the plating material 1 becomes lighter than the chain guide made of steel.

  When the base material 30 is an aluminum alloy, JIS standards A5052, A6061, A7075, etc. are used as an aluminum alloy, for example.

  A base plating layer 21 is laminated on the surface of the base material 30 of the sliding surface 11. A surface plating layer 22 is laminated on the base plating layer 21. That is, the plating layer 20 including the base plating layer 21 and the surface plating layer 22 is plated on the surface of the base material 30 of the sliding surface 11.

  The underlying plating layer 21 is a Ni—P amorphous plating layer. Since the structure of the base plating layer 21 is amorphous, it is possible to suppress the generation of micropores that occur over time, and it is possible to obtain a plating layer that is excellent in corrosion resistance. In general, as the time passes, the crystalline plating layer generates fine pores from the crystal interface and reaches the base of the plating layer, causing the base material and the base to come into contact with the outside air. However, even if the micropores are eroded from the crystalline surface plating layer, the erosion of the micropores can be suppressed if the underlying plating layer is amorphous.

  In the base plating layer 21, the film thickness d1 is 4 μm or more. When the film thickness d1 is 4 μm or more, the base plating layer 21 can be a plating layer with few pinholes and excellent corrosion resistance.

  For example, the base plating layer 21 contains P as an eutectoid element in an amount of 10 mass% (wt%) to 13 mass% (wt%). If P, which is a eutectoid element, is 15% by mass (wt%) or more in the base plating layer 21, amorphousness is easily lost. In the base plating layer 21, when P which is a eutectoid element exceeds 15 mass% (wt%), corrosion resistance will fall.

  A factor that determines the amorphous nature of the base plating layer 21 is the amount of P contained in the base plating layer 21. In general, in Ni—P plating, when the P content decreases, the structure becomes crystalline plating. Conversely, when the P content increases, the tendency for the structure to become amorphous increases. Although excellent corrosion resistance is obtained because the base plating layer 21 of the present embodiment is amorphous, the amount of P contained in the base plating layer 21 is at least 5 mass% (wt%) or more. The amount of P contained in the base plating layer 21 is more preferably 8% by mass (wt%) or more. Furthermore, the amount of P contained in the base plating layer 21 is preferably 10% by mass (wt%) or more. When the amount of P contained in the base plating layer 21 is lower than 5% by mass (wt%), coarse crystal grain boundaries are generated in the base plating layer 21 and the corrosion resistance of the base plating layer 21 is lowered.

Moreover, it is preferable that the quantity of P contained in the base plating layer 21 is 15 mass% (wt%) or less. When the amount of P contained in the base plating layer 21 increases, the hardness of the plating layer 20 itself tends to improve, but the amount of P contained in the base plating layer 21 is larger than 15% by mass (wt%). As a result, Ni ₃ P crystallized as a phosphide is likely to precipitate on the base plating layer 21. As a result, the amorphous property of the base plating layer 21 is lost, and the corrosion resistance of the base plating layer 21 is reduced.

  The surface plating layer 22 is a crystalline Ni plating layer. Thereby, the surface plating layer 22 exhibits high hardness, and it can be set as the plating layer 20 excellent in abrasion resistance. The crystalline surface plating layer 22 and the amorphous base plating layer 21 both have a better elongation than the anodic oxide film, and the influence of the strain is exerted on the base material 30 due to the external stress. Even if it exists, peeling of the plating layer 20 hardly occurs. Therefore, when the base material 30 is a material having a lower strength than steel, such as aluminum, copper, titanium, or magnesium, a characteristic that the original base material 30 does not have is added by plating.

  Moreover, it is preferable that the film thickness d2 of the surface plating layer 22 is 10 micrometers or more. When the film thickness d2 is thin, for example, due to the collision of the chain 2 or the like, sufficient resistance to the fracture stress brought from the outside to the surface plating layer 22 cannot be obtained, that is, the toughness of the surface plating layer 22 is lowered. Depending on the application, if the film thickness d2 of the surface plating layer 22 is at least 5 μm or more, more preferably 10 μm or more, the surface plating layer 22 is difficult to propagate cracks and delamination against an externally applied impact. It can be set as the plating layer 20 excellent in toughness.

  The surface plating layer 22 is an electroless plating layer as will be described later. When the surface plating layer 22 is subjected to X-ray analysis, the peak half-value width at the position of the Ni (200) plane in the X-ray analysis pattern is in the range of 0.3 to 1 °.

  The wear resistance of the surface plating layer 22 depends on the crystallite state of the surface plating layer 22. When the surface plating layer 22 is highly amorphous, the wear resistance is improved, and when the crystallite becomes fine, the wear resistance is lowered. In general, the crystallite size is determined by the Scherrer equation. That is, since the size of the crystallite is proportional to the reciprocal of the half width of the peak in X-ray diffraction, the state of the crystallite is quantified by measuring the half width of the peak by X-ray diffraction. Equation (1) is a Scherrer equation.

D = (K · λ) / (β · cos θ) (1)
here,
D: crystallite size (nm), β: half width (°), θ: Bragg angle of diffracted X-ray, λ: wavelength of measured X-ray (nm), K: constant 0 · 94
It is.

  In the X-ray diffraction pattern of the surface plating layer 22, it is preferable that the crystallite size is adjusted so that the peak half-width at the position of the Ni (200) plane is 1 ° or less. The peak half width at the position of the Ni (200) plane is more preferably 0.8 ° or less, still more preferably 0.6 ° or less, and the lower limit is preferably 0.3 ° or more. When the peak half-width at the position of the Ni (200) plane is smaller than 0.3 °, the crystallites of the surface plating layer 22 become large, and the strength of the surface plating layer 22 is derived from the hole-petch relationship. Since it decreases, there is a possibility that sufficient hardness cannot be obtained.

  In the X-ray diffraction described above, CuKα ray is used as an X-ray source, the tube voltage is 50 kV, the tube current is 200 mA, the scanning speed is 1 ° / min, and the diffraction angle 2θ is measured from 10 ° to 80 °. ing.

  The surface plating layer 22 has a Vickers hardness of 400 or more. The Vickers hardness of the surface plating layer 22 is more preferably 500 or more. Although depending on the application, in order to have sufficient performance as wear resistance, at least the surface plating layer 22 should have a Vickers hardness of 400 or more, more preferably 500 or more.

  For example, the thickness of the underlying plating layer 21 is 0.5 μm, the thickness of the surface plating layer 22 is 0.8 μm, the thickness of the intermediate plating layer is 0.5 μm, and the total thickness of the entire plating is 1. In the case of 8 μm, the indenter reaches the base plating layer 21 in the Vickers test. For this reason, the Vickers hardness of the surface plating layer 22 will be smaller than 400.

  FIG. 3 shows a first modification of the laminated structure of plating according to this embodiment. The same components as those described above are denoted by the same reference numerals and description thereof is omitted.

  A base plating layer 21 is laminated on the surface of the base material 30 of the sliding surface 11. A surface plating layer 22 is laminated on the base plating layer 21. A bright plating layer 40 is laminated on the surface plating layer 22. That is, on the surface of the base material 30 of the sliding surface 11, the plating layer 20 composed of the base plating layer 21, the surface plating layer 22, and the bright plating layer 40 are plated.

  The bright plating layer 40 is composed of at least one of black trivalent chromium (Cr) plating or black non-chromium alloy plating. Thereby, the corrosion resistance of the sliding surface 11 is increased without using a harmful plating solution such as hexavalent chromium. The thickness of the bright plating layer 40 is not less than 100 nm and not more than 400 nm.

  By providing the bright plating layer 40 on the plating layer 20, the sliding surface 11 is visually recognized as black as a whole, and is excellent in design.

  FIG. 4 shows a second modification of the laminated structure of plating according to this embodiment. The same components as those described above are denoted by the same reference numerals and description thereof is omitted.

  A base plating layer 21 is laminated on the surface of the base material 30 of the sliding surface 11. An intermediate plating layer 221 is laminated on the base plating layer 21. A surface plating layer 222 is laminated on the intermediate plating layer 221. A bright plating layer 40 is laminated on the surface plating layer 222. That is, on the surface of the base material 30 of the sliding surface 11, the plating layer 23 including the base plating layer 21, the intermediate plating layer 221, and the surface plating layer 222, and the bright plating layer 40 are plated. ing. Similar to FIG. 2, the bright plating layer 40 may not be provided as a second modification of the laminated structure of plating according to the present embodiment.

  Alternatively, the thickness d21 of the intermediate plating layer 221 is preferably 1 μm or more and 3 μm or less. If the thickness is less than 1 μm, the adhesion to the entire member is poor, and if it is 3 μm or more, the intermediate plating layer is hard and poor in toughness, so that the toughness of the surface plating layer may be reduced. Further, since the intermediate plating layer has a slow plating rate, if the film thickness is excessive, the productivity is significantly reduced.

  Here, the surface plating layer 222 is the same plating layer as the surface plating layer 21 shown in FIG. The film thickness d22 of the surface plating layer 222 is the same as the film thickness d2 of the surface plating layer 22 described above.

  The intermediate plating layer 221 is between the base plating layer 21 and the surface plating layer 222. The intermediate plating layer 221 is, for example, high sulfur content Ni plating. The intermediate plating layer 221 contains 0.05 mass% (wt%) or more and 0.2 mass% (wt%) or less of sulfur (S).

  Alternatively, the intermediate plating layer 221 is a Ni—P plating layer, and an amount of P different from the amount of P contained in the base plating layer 21 is contained in the intermediate plating layer 221. For example, the amount of P contained in the intermediate plating layer 221 is smaller than the amount of P contained in the base plating layer 21 and is more crystalline than the base plating layer 21.

  Any one of the plating treatment materials 1 described in the present embodiment, the first modified example of the present embodiment, and the second modified example of the present embodiment is a base material 30 that is inferior in strength to a steel material including aluminum. Is also suitable for the sliding member. The plating material 1 described in this embodiment, the first modification of this embodiment, or the second modification of this embodiment is excellent in corrosion resistance, wear resistance, and toughness.

[Production method]
Below, an example of the process of manufacturing the metal-plating processing material 1 which concerns on the 1st modification of the embodiment mentioned above is demonstrated.

(Base material preparation process)
An aluminum plate material (A7075-T6 material) cut to a thickness of 1.5 mm and 60 × 60 (mm) is prepared as the base material 30.

(Pretreatment process)
Examples of the pretreatment of the base material 30 to the aluminum alloy include a zinc substitution method, and in particular, a double zincate method (degreasing, etching, activation / surface adjustment as necessary, first zincate (zinc substitution), zincate peeling, 2-zincate (zinc substitution) Washing is preferably performed between the treatment steps, and known treatments conventionally used can be applied. This known process is called a double zincate method.

(Under plating process)
In the base plating treatment step, the Ni-P film is grown by immersing the product after the pretreatment step described above in a plating solution. As the plating solution, a conventionally known method or a commercially available plating solution can be applied.

When applying electroless Ni-P plating, it is usually composed of the following components.
Metal salt: As a nickel ion supply source, a water-soluble salt such as nickel sulfate or nickel chloride is used, and nickel is used in a concentration range of 2 to 10 g / l with 5 g / l as a standard.
Reducing agent: Hypophosphite, mainly sodium hypophosphite, is used in a concentration range of 5 to 50 g / l with 25 g / l as a standard.
Complexing agent: Although there is no restriction | limiting in particular as a seed, At least 1 or more types of amino acids, such as hydroxycarboxylic acids, such as a citric acid, malic acid, lactic acid, tartaric acid, and glycine, and alanine, are used.
In addition, monocarboxylic acids such as acetic acid and propionic acid, and dicarboxylic acids such as succinic acid, phthalic acid, and maleic acid can be added as a pH buffering agent. Furthermore, about 0.1-10 ppm of heavy metal salts, such as Pb and Bi, and S containing compound can also be added as a stabilizer.
Although it does not restrict | limit especially as process conditions, As temperature, 50-95 degreeC and pH 4.0-5.5 are general conditions.

On the other hand, when electric Ni-P plating is applied, it is usually composed of the following components.
Metal salt: Nickel sulfate, nickel chloride, etc. are mentioned as a nickel ion supply source, The density | concentration of these salts is 100-450 g / l.
Moreover, phosphorous acid, hypophosphorous acid, and its alkali metal salt are mentioned as a phosphorus supply source, The salt concentration is 5-100 g / l. In addition, pH buffer agents such as boric acid, phosphoric acid, carbonic acid, and aqueous ammonia, and conductive salts such as sulfuric acid and hydrochloric acid can be added.
The treatment conditions are usually pH 0.5 to 2.0, and the cathode current density is operated in the range of 1 to ²⁰ A / dm2.

(Surface plating process)
After the base plating process, a surface plating process is performed. The crystalline Ni plating is provided by, for example, electric Ni plating. After Ni-P plating in the base plating process, the product washed with water is immediately put into a crystalline plating bath, and Ni film formation is started.
A liquid typified by a Watt bath can be used as the plating bath, and it is usually used in the following composition.
Metal salt: As a metal supply source, nickel sulfate (NiSO ₄ .6H ₂ O) 280 g / l is used as a standard, and a concentration range of 200 to 350 g / l is used.
Conductive salt / anodic dissolution aid: Nickel chloride (NiCl ₂ .6H ₂ O) 50 g / l is used as a standard, and a concentration range of 30 to 80 g / l is used.
pH buffering agent: Boric acid (H ₃ BO ₃ ) is used in a concentration range of 10 to 60 g / l with 35 g / l as a standard.
It is also possible to add a known additive in the plating treatment bath containing these as a main component. For example, 0.5 to 3 g of a sulfur-containing compound such as saccharin or naphthalenedisulfonic acid as a primary brightener or stress reducer. / L, 0.1 to 2 g / L of 2-butyne-1,4-diol, propargyl alcohol, coumarin, etc. as a secondary brightener, and 10 to 1000 ppm of a surfactant such as sodium lauryl sulfate as a pit inhibitor. be able to.
The plating electrolysis conditions are such that the pH liquid temperature is 50 to 60 ° C., the current density is 1 to 5 A / dm ² , and the time is controlled according to the required film thickness. As described above, a plating film in which the plating film quality is crystalline is obtained.

(Black gloss plating process)
After the Ni plating in the surface plating process, the washed product is immediately put into the black plating bath and film formation is started. For the black trivalent chromium plating or the black non-chromium alloy plating, any known plating treatment bath can be used.

[Example]
Next, examples according to the present invention will be described. Plating treatment materials of Examples 1 to 8 and Comparative Examples 1 to 8 shown in Table 1 are prepared, half width measurement, corrosion resistance evaluation, wear resistance evaluation, and toughness evaluation are performed, and the results are summarized in Table 1. It was. Moreover, about the metal-plating process performed to Examples 1-8 and Comparative Examples 1-8, it is as showing below. NA in Table 1 indicates that P content is not detected. The intermediate plating layer between the base plating layer and the surface plating layer is a high sulfur content Ni plating, and sulfur (S) is 0.1 mass% (wt%).

<Examples 1, 5, 6, 8 and Comparative Examples 5, 6, 7, 8>
Base material: thickness 1.5 mm, 60 × 60 (mm) piece (aluminum plate (A7075-T6 material))
Pretreatment: Double zincate method (Nippon McDermid Co., Ltd.)
Base plating: Electroless Ni-P plating Nickel sulfate 5g / l as nickel
Sodium hypophosphite 25g / l
Sodium citrate 15g / l
Bi 2ppm
pH 5.0 Temperature 90 ° C
Surface plating: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 280g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 50g / l
Boric acid (H ₃ BO ₃ ) 35 g / l
Saccharin 2g / l
pH4.5 Temperature 50 ° C
Intermediate plated: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 300g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 60g / l
Boric acid (H ₃ BO ₃ ) 40 g / l
Saccharin 2g / l
Kaolin particles 5g / l with particle size of 1μm or less
pH 3.5 Temperature 50 ° C
Black plating: Black trivalent chromium plating (manufactured by Nihon McDermid Co., Ltd.)

<Example 2>
Base material: thickness 1.5 mm, 60 × 60 (mm) piece (aluminum plate (A7075-T6 material))
Pretreatment: Double zincate method (manufactured by Uemura Kogyo Co., Ltd.)
Base plating: Electroless Ni-P plating Nickel sulfate 4.5g / l as nickel
Sodium hypophosphite 25g / l
Glycine 20g / l
Malic acid 5g / l
Pb 1ppm
pH 5.0 Temperature 85 ° C
Surface plating: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 280g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 50g / l
Boric acid (H ₃ BO ₃ ) 35 g / l
Saccharin 2g / l
pH4.5 Temperature 50 ° C
Intermediate plated: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 300g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 60g / l
Boric acid (H ₃ BO ₃ ) 40 g / l
Saccharin 2g / l
Kaolin particles 5g / l with particle size of 1μm or less
pH 3.5 Temperature 50 ° C
Black plating: Black non-chromium alloy plating (Nippon Chemical Industry Co., Ltd.)

<Example 3>
Base material: thickness 1.5 mm, 60 × 60 (mm) piece (aluminum plate (A7075-T6 material))
Pretreatment: Double zincate method (Kisai Corporation)
Base plating: Electroless Ni-P plating Nickel sulfate 4.5g / l as nickel
Sodium hypophosphite 25g / l
Glycine 20g / l
Malic acid 5g / l
Boric acid 5g / l
pH 5.0 Temperature 85 ° C
Surface plating: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 250g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 45g / l
Boric acid (H ₃ BO ₃ ) 35 g / l
Saccharin 2g / l
2-butyne-1,4-diol 1g / l
pH4.5 Temperature 50 ° C
Intermediate plated: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 300g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 60g / l
Boric acid (H ₃ BO ₃ ) 40 g / l
Saccharin 2g / l
Kaolin particles 5g / l with particle size of 1μm or less
pH 3.5 Temperature 50 ° C
Black plating: Black non-chromium alloy plating (manufactured by Kizai Co., Ltd.)

<Examples 4 and 7, Comparative Example 3>
Base material: thickness 1.5 mm, 60 × 60 (mm) piece (aluminum plate (A7075-T6 material))
Pretreatment: Double zincate method (Nippon McDermid Co., Ltd.)
Base plating: Electroless Ni-P plating Nickel sulfate 5g / l as nickel
Sodium hypophosphite 25g / l
Sodium citrate 15g / l
Bi 2ppm
pH 3.5 Temperature 90 ° C
Surface plating: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 280g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 50g / l
Boric acid (H ₃ BO ₃ ) 35 g / l
Saccharin 2g / l
pH4.5 Temperature 50 ° C
Intermediate plated: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 300g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 60g / l
Boric acid (H ₃ BO ₃ ) 40 g / l
Saccharin 2g / l
Kaolin particles 5g / l with particle size of 1μm or less
pH 3.5 Temperature 50 ° C
Black plating: Black non-chromium alloy plating (Nippon Chemical Industry Co., Ltd.)

<Comparative Example 1>
Base material: thickness 1.5 mm, 60 × 60 (mm) piece (aluminum plate (A7075-T6 material))
Pretreatment: Double zincate method (Nippon McDermid Co., Ltd.)
Base plating: untreated surface plating: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 280g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 50g / l
Boric acid (H ₃ BO ₃ ) 35 g / l
Saccharin 2g / l
pH4.5 Temperature 50 ° C
Black plating: Black trivalent chromium plating (manufactured by Nihon McDermid Co., Ltd.)

<Comparative example 2>
Base material: thickness 1.5 mm, 60 × 60 (mm) piece (aluminum plate (A7075-T6 material))
Pretreatment: Double zincate method (Nippon McDermid Co., Ltd.)
Base plating: Electroless Ni-P plating Nickel sulfate 5g / l as nickel
Sodium hypophosphite 25g / l
Sodium citrate 15g / l
Bi 2ppm
pH 5.0 Temperature 90 ° C
Surface plating: Untreated black plating: Black trivalent chromium plating (manufactured by Nihon McDermid Co., Ltd.)

<Comparative Example 4>
Base material: thickness 1.5 mm, 60 × 60 (mm) piece (aluminum plate (A7075-T6 material))
Pretreatment: Double zincate method (Nippon McDermid Co., Ltd.)
Base plating: Electroless Ni-P plating Nickel sulfate 5g / l as nickel
Sodium hypophosphite 25g / l
Sodium citrate 15g / l
Bi 2ppm
pH 6.5 Temperature 90 ° C
Surface plating: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 280g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 50g / l
Boric acid (H ₃ BO ₃ ) 35 g / l
Saccharin 2g / l
pH4.5 Temperature 50 ° C
Intermediate plated: Ni electroplating nickel sulfate _{(NiSO 4 · 6H 2 O)} 300g / l
Nickel chloride _{(NiCl 2 · 6H 2 O)} 60g / l
Boric acid (H ₃ BO ₃ ) 40 g / l
Saccharin 2g / l
Kaolin particles 5g / l with particle size of 1μm or less
pH 3.5 Temperature 50 ° C
Black plating: Black non-chromium alloy plating (Nippon Chemical Industry Co., Ltd.)

(Evaluation of composition of base plating)
The plating treatment materials of Examples 1 to 8 and Comparative Examples 2 to 8 were cut into 20 × 20 (mm), and an electron probe microanalyzer (EPMA-1610: manufactured by Shimadzu Corporation) was used to check the surface of the plating treatment material. At an arbitrary point, qualitative and semi-quantitative elemental analysis was performed at an acceleration voltage of 15 kV, and the P content in the underlying plating layer was measured.

(Evaluation of plating hardness)
In the plated materials of Examples 1 to 8 and Comparative Examples 1 to 8, 40 g according to JISZ2244 “Vickers hardness test—test method” using a microhardness tester (HM-220: manufactured by Mitutoyo Corporation). The Vickers hardness was measured with a load of 1 and summarized in Table 1.

(Measurement of plating film thickness)
The specimen thicknesses of the samples before and after the plating treatments of Examples 1 to 8 and Comparative Examples 1 to 8 were measured with a micrometer, and the film thickness was calculated from the difference. Samples having a film thickness of 1 μm or less were measured by cross-sectional observation with SEM (SEM ULTRAplus: manufactured by Carl Zeiss).

(Corrosion resistance test)
The samples (60 × 60 test pieces) in Examples 1 to 8 and Comparative Examples 1 to 8 were evaluated for corrosion resistance by a salt spray test in accordance with JISH8502 “Plating corrosion resistance test method”. Masked with PTFE tape so that the 50 × 50 corner of the central part on one side of each sample is exposed, installed in a cast testing machine, sprayed salt water on the exposed surface, and evaluated the corrosion resistance. (JISZ2371 salt spray test method).
Regarding corrosion resistance, a case where the pitting corrosion score due to the corrosion product of the Al material generated by the corrosion reaching the base material is less than 5 points is judged as “corrosion resistance (◯)”, and a case where 5 points or more occurred It was determined as “insufficient corrosion resistance (×)”.

(CASS test conditions)
For sodium chloride items, conditions of 50 ± 5 g / l are used.
For the item of cupric chloride, a condition of 0.26 ± 0.02 g / l is used.
For the pH item, the conditions of 3.0 to 3.2 are used.
The condition of 1.5 ± 0.5 ml / 80 cm ² / h is used for the spray amount item.
The condition of 50 ± 2 ° C. is used for the test chamber temperature item.
For the item of salt water tank temperature, the condition of 63 ± 2 ° C. is used.
For the item of compressed air pressure, a condition of 70 to 167 kPa is used.

(Evaluation of toughness)
In a friction and wear tester (FPR-2100: manufactured by Reska Co., Ltd.), a high-bearing steel pin (SUJ2) processed so that the tip angle is 90 ° and R is 0.1 mm is attached to the wearer. The pins were rotationally moved so that the surfaces of the samples in Examples 1 to 8 and Comparative Examples 1 to 8 were marked. The wearer is moved while rotating outwardly so as to vortex from the center. The evaluation conditions are as follows.
Load: 3 kg, rotation speed: 50 rpm, initial radius: 4 mm, end radius: 10 mm
Wear: SUJ2 pin, R: 0.1 mm

  FIG. 5 is an explanatory diagram for explaining the marking fracture area of Example 1 and the marking damage area of Comparative Example 2. The marking line generated on the surface of the sample was observed with a microscope (VHHX-1000: Digital microscope manufactured by Keyence Corporation), and the width L of the fracture area (cracking or peeling area) extending outward from the marking line (see FIG. 5). ) Were measured, and those having a fracture area of less than 3 μm were determined to be “tough” (◯), and those having a fracture area of 3 μm or more were determined as “insufficient toughness (×)”.

  In the above, various useful examples of the present invention have been shown and described. The present invention is not limited to the various embodiments and modifications described above, and various modifications can be made without departing from the gist of the present invention and the contents described in the appended claims. There is no.

DESCRIPTION OF SYMBOLS 1 Plating treatment material 2 Chain 11 Sliding surface 21 Base plating layer 22, 222 Surface plating layer 30 Base material 40 Bright plating layer 221 Intermediate plating layer

Claims (7)

A plating treatment material based on aluminum, provided with at least two plating layers,
The two plating layers have a base plating layer and a surface plating layer,
The base plating layer is made of an amorphous Ni plating layer having a thickness of 4 μm or more,
A plating treatment material, wherein the surface plating layer is made of a Ni-P-based crystalline plating layer having a thickness of 10 μm or more.   The plating treatment material according to claim 1, wherein the base plating layer is a Ni—P plating layer containing 10% by mass or more and 13% by mass or less of P.   2. The electroless plating layer according to claim 1, wherein the surface plating layer is an electroless plating layer having a peak half width at a position of the Ni (200) plane in the X-ray analysis pattern in a range of 0.3 to 1 °. The plating treatment material according to 2.   The plating material according to any one of claims 1 to 3, wherein the surface plating layer has a Vickers hardness of 500 or more.   An intermediate plating layer composed of at least one of high sulfur content Ni plating or Ni-P plating with a film thickness of 1 μm to 3 μm is provided between the base plating layer and the surface plating layer. The plating material according to any one of claims 1 to 4.   2. A plating layer comprising at least one of black trivalent Cr plating or black non-chromium alloy plating having a thickness of 100 nm to 400 nm is provided on the surface plating layer. The plating treatment material according to claim 5.   The plating material according to any one of claims 1 to 6 is used as a sliding member, and has a sliding surface having the base plating layer and the surface plating layer. A sliding member characterized.