JPH11350197A - Composite plating method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a composite plating method which deposits a metallic matrix at a regulated thickness and uniformly codeposits ceramic particles on the metallic matrix. SOLUTION: This composite plating method consists in arranging a cylindrical electrode 10 apart a spacing within the hollow part of a cylinder block 2, supplying a composite plating liquid, which is prepd. by mixing ceramic particles 52 with a plating liquid, into the inner holes of the cylindrical electrode 10, injecting the supplied composite plating liquid through the through-holes 13 formed at the peripheral wall of the cylindrical electrode 10, applying the plating liquid to the inside wall 2b of the hollow part and recovering the composite plating liquid applied to the inside surface 2b from the outer side of the cylindrical electrode 10. In such a case, the injection rates from the through-holes 13 are kept nearly the same.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite plating method for forming a composite plating film on the inner surface of a hollow portion of a work.

[0002]

2. Description of the Related Art A cylinder block for an internal combustion engine is, for example, one in which a cylinder inner surface serving as a sliding surface of a piston ring is cast and formed integrally with the cylinder block, and a Ni / SiC composite plating film is applied to the cylinder inner surface. is there. Ni
The / SiC composite plating film is obtained by co-depositing silicon carbide (SiC) particles in a Ni matrix, which is a metal phase, and has improved wear resistance on the inner surface of the cylinder.

On the other hand, a high-speed plating method is disclosed in Japanese Unexamined Patent Publication No. Hei 7-118891, "Surface treatment apparatus".
According to this high-speed plating method, the composite plating solution can be forcibly flowed along the inner surface of the cylinder, and the composite plating film can be applied to the inner surface of the cylinder at high speed. The following figure shows the Ni / SiC composite plating film treatment by the apparatus of the publication.

FIG. 9 is an explanatory view of a conventional Ni / SiC composite plating process. Opening 101 of cylinder block 100
By disposing a cylindrical electrode 102 with a gap S in the inside, an annular passage 104 is formed between the opening 101 and the electrode 102.
To form A composite plating solution is flowed through the annular passage 104 as shown by the arrow, and then around the top of the electrode 102, the electrode 10
The flow is turned inward as shown by the arrow in FIG. While continuing the flow of the composite plating solution, the electrode 102
And the cylinder block 100, the SiC particles 107 in the Ni matrix 106 of the composite plating film 105.
... (... indicates a plurality (number). The same shall apply hereinafter).

[0005]

However, the composite plating film 105 shown in FIG. 9 has a problem shown in the following figure. FIG. 10 is an enlarged view of part 10 of FIG. Since the composite plating solution flows in the direction of the arrow along the annular passage 104, the N
A large amount of SiC particles 107 are eutectoid in the i matrix 106. Therefore, as the composite plating solution flows upward (downstream side), the SiC particles 107 in the composite plating solution decrease, and the eutectoid amount of the SiC particles 107 gradually decreases toward the downstream side. For this reason, there is a problem that the wear resistance of the composite plating film decreases on the downstream side.

FIG. 11 is an illustration of the flow rate of a conventional Ni / SiC composite plating solution. The composite plating solution 109 flows along the annular passage 104 as shown by a white arrow. At this time, the flow rate of the composite plating solution 109 on the surface side of the opening 101 becomes small due to the resistance of the surface of the opening 101 as shown by the white arrow. Therefore, the Ni ions 108 in the composite plating solution 109 are collected at the central side where the flow velocity is large, and the Ni ion concentration on the surface side of the opening 101 becomes lower than the specified concentration. As a result, there is a possibility that the Ni matrix 106 of the composite plating film 105 cannot be deposited to a specified thickness.

Accordingly, an object of the present invention is to provide a composite plating method capable of depositing a metal matrix to a specified thickness, and furthermore capable of uniformly depositing ceramic particles on the metal matrix.

[0008]

In order to achieve the above-mentioned object, a first aspect of the present invention is to dispose a cylindrical electrode in a hollow portion of a work with a gap therebetween, and to form a plating solution inside a cylindrical electrode with a plating solution. A composite plating solution mixed with particles is supplied, and the supplied composite plating solution is jetted through a plurality of through-holes formed in the peripheral wall of the cylindrical electrode and applied to the inner surface of the hollow portion, and the composite plating solution hitting the inner surface is formed into a cylindrical shape. A composite plating method for recovering from the outside of an electrode, characterized in that jetting speeds from the plurality of through holes are substantially the same.

By jetting the composite plating solution from the plurality of through holes and applying the composite plating solution substantially perpendicularly to the inner surface of the hollow portion, the composite plating solution hitting the inner surface of the hollow portion becomes turbulent. In addition, by making the injection speed of the composite plating solution from the injection holes substantially the same, the collision conditions of the composite plating solution with the hollow portion are averaged. For this reason, metal ions and ceramic particles can be uniformly dispersed in the composite plating solution. As a result, the metal ion concentration in the composite plating solution can be maintained at a specified concentration near the inner surface. Further, the ceramic particles in the composite plating solution can be uniformly dispersed near the inner surface.

A second aspect of the present invention is characterized in that the cylindrical electrode is rotated when the composite plating solution is jetted through the plurality of through holes. By rotating the cylindrical electrode, the composite plating solution sprayed from the plurality of through holes can be more uniformly applied to the entire inner surface of the hollow portion. For this reason, the metal phase matrix can be deposited to a more uniform thickness over the entire inner surface, and the ceramic particles can be uniformly co-deposited in the metal phase matrix.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. The drawings should be viewed in the direction of reference numerals. FIG. 1 is an overall view showing a composite plating apparatus according to the present invention. The composite plating apparatus 1 is arranged in a work mounting table 6 mounted on a main body 4 for mounting a cylinder block (work) 2 for an internal combustion engine, and in a hollow portion 2a of the cylinder block 2 mounted on the work mounting table 6. Cylindrical electrode 1
0, a rotation mechanism 20 for rotating the cylindrical electrode 10 around the axis 10 a of the cylindrical electrode 10, and a plating solution circulation mechanism 30 for supplying a composite plating solution 29 to the inner hole (inside) 11 of the cylindrical electrode 10. And an energizing mechanism 45 for energizing the cylinder block 2 and the cylindrical electrode 10. In addition, the cylindrical electrode 1
0 will be described in detail with reference to FIGS. 2b is an inner surface of the hollow portion 2a, 2c is a water jacket serving as a cooling water passage, 2d is a crank chamber, and 3 is an annular passage of a gap S1 formed by the inner surface 2b and the cylindrical electrode 10.

The work mounting table 6 is a member having an insulating member 7 on a work receiving surface 6a and a recovery hole 6b for a composite plating solution. The insulating member 7 is a plate material formed of, for example, ceramic or synthetic resin. The reason why the insulating member 7 is provided is to insulate the cylinder block 2 from the work mounting table 6 and apply electricity only to the cylinder block 2, thereby efficiently applying a composite plating film to the inner surface 2 b of the cylinder block 2. The reason why the work mounting table 6 is provided with the recovery hole 6b is that the composite plating solution 29 hitting the inner surface 2b of the cylinder block 2 is recovered from the recovery hole 6b, and the composite plating solution 29 is smoothly circulated. This is because the composite plating film is efficiently applied to the inner surface 2b of the substrate 2.

Next, the rotation mechanism 20 will be described. The rotating mechanism 20 is a mechanism that is applied to a cylinder block for a four-cylinder engine and rotates four cylindrical electrodes 10. Here, the description will be made on the content of rotating one cylindrical electrode 10. The rotation mechanism 20 includes a motor 21 attached to the main body 4 and a drive shaft 2 connected to the motor 21.
2 and a drive gear 23 attached to the drive shaft 22
, A gear 24 meshed with the drive gear 23, and the gear 2
4 is attached substantially at the center and the threaded portion 1 of the cylindrical electrode 10 is provided at the upper end.
4 to which a support shaft 25 is attached. The mechanism for rotating the four cylindrical electrodes 10 will be described in detail with reference to FIG.

[0014] The plating solution circulation mechanism 30
9, a first supply path 33 extending from the tank 31 to the supply port 32, a pump 34 provided in the middle of the first supply path 33, and a chamber 35 formed on the outlet side of the supply port 32. And a second supply passage 3 opened in the support shaft 25 so that the entrance side 36a communicates with the chamber 35.
6 and a cylindrical electrode 10 communicating with the outlet side of the second supply path 36.
, An annular passage 3 communicating with the inner hole 11 through a through-hole 13, a collecting port 37 communicating with the annular passage 3 through a collecting hole 6 b of the work mounting table 6, and a collecting port 3.
It comprises a recovery path 38 extending from 7 to the tank 31, a control valve 39 provided in the middle of the recovery path 38, and a stirrer 40 attached to the tank 31.

The control valve 39 is connected to the crank chamber 2
This is a valve for adjusting the liquid level 29a of the composite plating solution 29 in d. The stirrer 40 stirs the composite plating solution 29 in the tank 31 with the wing 41. Power supply mechanism 45
Is connected to the lower end of the support shaft 25 by a rotary connector 4 for energization.
6, an anode 47 is connected to the rotary connector 46, and a cathode 48 is connected to the cylinder block 2.

FIG. 2 is a sectional view taken along line 2-2 of FIG. The drive gear 23 of the rotating mechanism 20 meshes with the inner gears 24, 24, and the inner gears 24, 24 mesh with the first and second transmission gears 26, 27, respectively, and the first and second transmission gears 26, 27 respectively.
27 meshes with the outer gears 24,24. Therefore, the rotational force of the motor 21 is first transmitted from the drive gear 23 to the inner gears 24, 24 as shown by arrows, and then from the inner gears 24, 24 to the first and second transmission gears 26, 24 as shown by arrows. 27, and then the first and second transmission gears 2
Outer gears 24,2 from arrows like 6,27
Transfer to 4. As a result, the rotating shaft 2 with the gears 24.
5 rotate as indicated by the outline arrows, respectively,
The cylindrical electrode 10 (see FIG. 1) attached to the rotating shaft 25
Each of them rotates like the white arrow.

FIGS. 3A and 3B are explanatory views of a cylindrical electrode according to the present invention, wherein FIG. 3A is a sectional view, and FIG. In (a), the cylindrical electrode 10 is, for example, an electrode in which a titanium (Ti) base material is clad with platinum (Pt) or an electrode in which a Ti base material is clad with iridium oxide (IrO ₂ ). 1 and the inner surface 2b of the cylinder block 2 (FIG. 1).
Shown in ) And a cylindrical peripheral wall 12 facing the peripheral wall 12.
, A plurality of through holes 13 spirally arranged, a lid portion 14 formed at an upper end portion, and a screw portion 15 formed at a lower end portion. In (b), the cylindrical electrode 10 is set to a height H (see (a)) and a circumferential length L of the peripheral wall 12, and the through holes 13 are arranged in the peripheral wall 12 at a constant angle θ (24 °). Things. The arrangement of the through holes 13 will be described in detail with reference to FIG.

FIG. 4 is a developed view of the cylindrical electrode according to the present invention. The through holes 13 are staggered in the peripheral wall 12 and have an inclination angle θ.
Are arranged at a pitch P along the spiral. The reason why the through holes 13 are spirally arranged is to uniformly apply the composite plating solution 29 to the inner surface 2b (shown in FIG. 1) of the cylinder block 2 facing the peripheral wall 12. Moreover, the reason why the through holes 13 are arranged in a staggered manner is that the distance between the through holes 13 is smaller than that in the grid pattern,
This is because the through holes 13 are densely arranged in the peripheral wall 12.

Next, the composite plating method will be described with reference to FIGS. FIG. 5 is a first explanatory view of the composite plating method according to the present invention, and shows a principle diagram of the composite plating method. First, the cylinder block 2 is connected to the insulating member 7 of the work table 6.
To cover the cylindrical electrode 10 with a gap S1 opened. Next, the motor 21 is driven, and the rotational force of the motor 21 is transmitted to the driving gear 23 → the gear 24 → the support shaft 25 so that the cylindrical electrode 10
Is rotated about the axis 10a. Next, the stirrer 40
Is rotated to agitate the composite plating solution 29 in the tank 31. In this state, the pump 34 is driven to drive the tank 3
1 as indicated by arrows a1 to a3.
The gas is supplied to the inner hole 11 of the cylindrical electrode 10 through the supply path 33 → the supply port 32 → the chamber 35 → the second supply path 36.

The composite plating solution 29 in the inner hole 11 is
3, and is ejected to the outside of the cylindrical electrode 10 as shown by an arrow b and strikes the inner surface 2 b of the cylinder block 2 at right angles. Then, the composite plating solution 29 that has hit the inner surface 2b of the cylinder block 2 is recovered in the tank 31 through the annular passage 3 → the recovery port 37 → the recovery path 38 as shown by arrows c1 and c2. With the composite plating solution 29 circulated, the energizing mechanism 45 is operated to energize the cylindrical electrode 10 and the cylinder block 2.

FIG. 6 shows a second example of the composite plating method according to the present invention.
It is an explanatory view, and shows a state in which a composite plating solution 29 is sprayed from the through holes 13 of the cylindrical electrode 10. By jetting the composite plating solution 29 from the through holes 13 and hitting the inner surface 2b of the cylinder block 2 almost at right angles as indicated by arrows b, the composite plating solution 29 hitting the inner surface 2b becomes turbulent. In addition, by making the injection speed of the composite plating solution 29 from the injection holes 13 approximately the same, the collision conditions of the composite plating solution 29 on the inner surface 2b are averaged. Therefore, metal ions 5
And the ceramic particles 52 can be uniformly dispersed in the composite plating solution 29.

As a result, the metal ion concentration in the composite plating solution 29 can be maintained at a specified concentration in the vicinity of the inner surface 2b, so that the metal matrix 51 of the composite plating film 50 can be maintained.
Can be deposited to a specified thickness T. Also, inner surface 2
b, the ceramic particles 5 in the composite plating solution 29
2 can be uniformly dispersed, so that the ceramic particles 52 can be co-deposited uniformly in the metal matrix 51.

Furthermore, by rotating the cylindrical electrode 10, the composite plating solution 29 sprayed from the through holes 13 can be uniformly applied to the entire inner surface 2b of the cylinder block 2. Therefore, the metal matrix 5 is formed over the entire inner surface 2b.
1 can be deposited to a uniform thickness, and the ceramic particles 52 can be co-deposited uniformly in the metal matrix 51.

FIG. 7 shows a third example of the composite plating method according to the present invention.
It is explanatory drawing and shows the state which expanded the cylindrical electrode on the right side of the sectional view of the cylinder block 2. FIG. For convenience, the through hole 13
Are described by adding a to j. The cylindrical electrode 10 is rotated while spraying the composite plating solution 29 (see FIG. 5) from the through holes 13a to 13j. As a result, first, the through hole 13a
Of the composite plating solution 29 sprayed from the inner surface 2b of the cylinder block 2 as shown by an arrow,
The composite plating solution 29 sprayed from above is shifted slightly above the position P1 and applied. Next, the composite plating solution 29 sprayed from the through hole 13c is applied to the position P2 as shown by the arrow,
The composite plating solution 29 jetted from 3d is applied slightly above the position P2, and the composite plating solution 29 jetted from the through hole 13e is applied to the position P3 as shown by an arrow.

Further, the composite plating solution 29 sprayed from the through hole 13f is applied to the inner surface 2 of the cylinder block 2 as shown by the arrow.
The composite plating solution 29 sprayed from the through holes 13g and 13h is sequentially shifted slightly above the position P4 and applied to the position P4 of b. Next, the composite plating solution 29 sprayed from the through holes 13j is applied to the position P5 as shown by the arrow.

For this reason, the inner surface 2b of the cylinder block 2
The composite plating solution 29 can be uniformly applied to the area E of the positions P1 to P6. As a result, the composite plating solution 2
9, the metal matrix 51 can be deposited to a specified thickness while maintaining the metal ion concentration in the specified concentration, and the ceramic particles 52... It can be uniformly eutectoid therein.

FIG. 8 shows a glass in which the composite plating according to the present invention is compared with the conventional composite plating. The horizontal axis shows the plating position between the cylinder head side end P7 and the crankcase side end P8 of the inner surface 2b of the cylinder block 2, and the vertical axis shows the ceramic particles (Si ₃ N ₄ particles) 52 in the composite plating film 50. .. (See FIG. 6). The bold solid line is a graph of an example in which the composite plating film 50 is applied by the composite plating apparatus 1 (shown in FIG. 1) according to the present invention, and the thin solid line is that in which the composite plating film 50 is applied by the conventional apparatus shown in FIG. It is a graph of a comparative example. As the composite plating solution 29, a plating solution containing Ni ions and P ions as metal ions and suspending silicon nitride (Si ₃ N ₄ ) particles as ceramic particles was used.

According to the embodiment, the ceramic particles (Si ₃ N ₄ particles) 52... From the end P 7 on the cylinder head side to the end P 8 on the crank chamber side of the inner surface 2 b of the cylinder block 2.
It can be seen that the amount of eutectoid was kept constant. On the other hand, according to the comparative example, the eutectoid amount of ceramic particles (Si ₃ N ₄ particles) 52 gradually decreases from the cylinder head side end P7 of the inner surface 2b of the cylinder block 2 to the crank chamber side end P8. You can see that

According to the embodiment, the composite plating film 5
0 metal matrix (Ni-9P matrix) 51
(Shown in FIG. 6) can be deposited to a specified thickness T. On the other hand, according to the comparative example, the metal matrix (Ni-9P matrix) 51 of the composite plating film 50 is deposited to a specified thickness T. Turned out to be impossible. Therefore, according to the embodiment, the wear resistance of the inner surface 2b of the cylinder block 2 can be uniformly increased.

The same effect was obtained by using a plating solution containing Ni ions as metal ions and suspending silicon carbide (SiC) particles as ceramic particles.

[0031]

EXAMPLES Examples of the present invention will be described below with reference to Tables 1 and 2. However, the present invention is not limited to these experimental examples.

[0032]

[Table 1]

Experiment No. 1: the composite plating solution 29 (see FIG. 1) is nickel sulfate (NiSO ₄ ) 45 to 70 g / l
(Liter), 250 g of sodium sulfate (Na ₂ SO ₄ )
/ L, boric acid 40 g / l and phosphorous acid 40 g / l, pH = 2.5, and silicon nitride (Si ₃ N ₄ ) particles 4
It is a suspension of 5 g / l. A cylindrical electrode 10 (FIG. 1)
) Has 169 through holes 13 with a hole diameter of 2.0 mm in the peripheral wall 12.

While rotating the cylindrical electrode at 5 rpm, the composite plating solution 29 is circulated at a flow rate of 30 l / min, and the current density is set in the range of 10 A / dm ^{2 to} 12.5 A / dm ² to form the cylindrical electrode 10. And the cylinder block 2 were energized for 72 minutes. As a result, the composite plating film could have a specified thickness of 100 μm, and Si ₃ N ₄ particles could be co-deposited uniformly in the Ni-9P matrix of the composite plating film. Therefore, the wear resistance of the inner surface 2b of the cylinder block 2 can be uniformly increased.

[0035]

[Table 2]

Experiment No. 2: The composite plating solution 29 is composed of nickel sulfate (NiSO ₄ ) 400 g / l and boric acid 35 g /
l, pH with addition of 2.5 g / l of saccharin sodium =
2.5 is obtained by suspending 60 g of silicon carbide (SiC) particles. The cylindrical electrode 10 was used in Experiment No. 1, a through hole 13 having a hole diameter of 2.0 mm is formed in the peripheral wall 12.
69 were opened. While rotating the cylindrical electrode at 5 rpm, the composite plating solution 29 was circulated at a flow rate of 30 l / min, the current density was set to 64 A / dm ² , and the cylindrical electrode 1
0 and the cylinder block 2 were energized for 7 minutes. As a result, Experiment No. 1, the composite plating film can have a specified thickness of 100 μm.
The SiC particles could be co-deposited uniformly in the i matrix. Therefore, the wear resistance of the inner surface 2b of the cylinder block 2 can be uniformly increased.

In the above Experiment No. 1, the metal ion (Ni
Ions, P ions) 51a and ceramic particles (Si ₃
The metal matrix (Ni-9P matrix) is made of Si ₃ N ₄ using a composite plating solution 29 containing N ₄ particles) 52.
The content of eutectoid particles was explained, and experiment N
o. 2, a composite plating solution 2 containing metal ions (Ni ions) 51a and ceramic particles (SiC particles) 52
9 using a metal matrix (Ni matrix) 5
Although the content of co-depositing the ceramic particles (SiC particles) 52 in the embodiment 1 has been described, a composite plating solution containing other metal ions or ceramic particles may be used. In the above-described experimental example, the content of applying the composite plating film to the inner surface 2b of the cylinder block 2 has been described. However, it is also possible to apply the composite plating film to the inner surface of the hollow portion of another work. In the above-described experimental example, the description has been given of the case where the composite plating film is applied to the cylinder block 2 of the four-cylinder engine using the four cylindrical electrodes 10. However, the number of the cylindrical electrodes 10 is changed to, for example, six cylinders. It is also possible to apply to a cylinder block or the like of an engine.

In the above experimental example, the inner hole 1 of the cylindrical electrode 10 was
Although the description has been given of the content in which 1 is closed by the lid 14, the inner hole 11 may be closed by the bottom of the cylindrical electrode. At this time, the composite plating solution is supplied to the inside hole 11 from the top side opposite to the bottom. In the above-described experimental example, the content in which the insulating member 7 is attached to the work receiving surface 6a of the work mounting table 6 has been described.
In addition, the same effect can be obtained by applying an insulating coating such as a ceramic coating or a resin coating.

[0039]

According to the present invention, the following effects are exhibited by the above configuration. According to the first aspect of the present invention, the composite plating solution hitting the inner surface of the hollow portion becomes turbulent by spraying the composite plating solution from the plurality of through holes and applying the composite plating solution substantially perpendicularly to the inner surface of the hollow portion. In addition, by making the injection speed of the composite plating solution from the injection holes substantially the same, the collision conditions of the composite plating solution with the hollow portion are averaged. For this reason, metal ions and ceramic particles can be uniformly dispersed in the composite plating solution.

As a result, the metal ion concentration in the composite plating solution can be maintained at a specified concentration near the inner surface, so that the metal phase matrix of the composite plating film can be deposited to a specified thickness. Further, since the ceramic particles in the composite plating solution can be uniformly dispersed in the vicinity of the inner surface, the ceramic particles can be co-deposited uniformly in the metal phase matrix.

According to the second aspect, by rotating the cylindrical electrode, the composite plating solution sprayed from the plurality of through holes can be uniformly applied to the entire inner surface of the hollow portion. For this reason, the metal phase matrix can be deposited to a uniform thickness over the entire inner surface, and the ceramic particles can be uniformly co-deposited in the metal phase matrix.

[Brief description of the drawings]

FIG. 1 is an overall view showing a composite plating apparatus according to the present invention.

FIG. 2 is a sectional view taken along line 2-2 of FIG.

FIG. 3 is an explanatory view of a cylindrical electrode according to the present invention.

FIG. 4 is a development view of a cylindrical electrode according to the present invention.

FIG. 5 is a first explanatory view of a composite plating method according to the present invention.

FIG. 6 is a second explanatory view of the composite plating method according to the present invention.

FIG. 7 is a third explanatory view of the composite plating method according to the present invention.

FIG. 8 shows a glass in which the composite plating according to the present invention is compared with the conventional composite plating.

FIG. 9 is an explanatory view of a conventional Ni / SiC composite plating process.

FIG. 10 is an enlarged view of part 10 in FIG. 9;

FIG. 11 is an explanatory diagram of a flow rate of a conventional Ni / SiC composite plating solution.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Composite plating apparatus, 2 ... Cylinder block (work), 2a ... Hollow part, 2b ... Inner surface, 10 ... Cylindrical electrode, 1
DESCRIPTION OF SYMBOLS 1 ... Inside hole (inside), 12 ... Peripheral wall, 13 ... Through-hole, 29
... composite plating solution, 52 ... ceramic particles (Si ₃ N ₄ particles, SiC particles), S1 ... gap.

Claims (2)

[Claims] 1. A cylindrical electrode is disposed in a hollow portion of a workpiece with a gap therebetween, and a composite plating solution in which ceramic particles are mixed with a plating solution is supplied to the inside of the cylindrical electrode. A composite plating method of spraying through a plurality of through-holes formed in the peripheral wall of the electrode and hitting the inner surface of the hollow portion, and recovering the composite plating solution hitting the inner surface from the outside of the cylindrical electrode, comprising: A composite plating method characterized in that the injection speeds of the two are substantially the same. 2. The composite plating method according to claim 1, wherein a cylindrical electrode is rotated when the composite plating solution is jetted through the plurality of through holes.