JPS5933680B2 - Metsuki method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a plating apparatus in which a plating solution is circulated upward from the bottom of a plating tank, and particularly to a plating method applied to a composite plating apparatus.

Conventionally, when performing plating processing, especially composite plating processing, it is necessary to shorten plating time, remove hydrogen bubbles that adhere to the cathode surface, prevent blooming, equalize the distribution of suspended solids in the plating layer, and layer the plating layer. It has become common practice to stir the plating solution for the purpose of making the thickness uniform and improving the smoothness of the plating surface.
One way to stir this plating solution is to provide a plating solution storage tank attached to the plating tank and circulate the plating solution between the two tanks.
There is a method of stirring the plating solution by flowing it upward from the bottom, and this stirring method has various advantages.

However, stirring the plating solution through this circulation alone may result in insufficient agitation and the above-mentioned agitation effect may not be achieved satisfactorily. Especially in composite plating, it is necessary to disperse and homogenize suspended substances in the plating solution. In this respect, more reliable stirring was desired. Figure 1 shows a conventionally used composite plating device in which the plating solution is circulated from the bottom of the plating tank upwards. The plating solution storage tank 2 is provided with a plating solution storage tank 2, and the plating solution is supplied from the plating solution storage tank 2 to the lower part of the plating processing tank 1 by a pump 3 as shown by the arrow. The plating solution in the plating tank 1 flows from bottom to top, and the plating solution overflowing into the plating solution recovery chamber 4 from the upper part of the plating tank 1 is collected into the plating solution storage tank 2. A metal body to be plated (anode electrode) 5 and a body to be plated (cathode electrode) 6 are placed in the plating tank 1, and each is connected to a plating power source (not shown) to perform the plating process. Nasu) be done. To explain this apparatus in more detail, the plating treatment tank 1
Inside, from the bottom, there are electrically insulating packing T, anode extraction plate 8, electrically insulating packing 9, cathode extraction plate 10, electrically conductive packing 110, body to be plated (cathode) 6, electrically insulating packing 13, and plating solution recovery. Toys 14 are arranged. Furthermore, each of these parts has a hole with the same diameter as the inner diameter of the cylindrical body to be plated 6 approximately in the center thereof, and these centers are arranged so that they are all lined up on the same axis, and the plating liquid passage 15 is formed. A plating solution inflow conduit 16 is connected to the bottom of the passage 15. The above anode extraction plate 8
In the center of the hole is a metal body (anode) support part I to be plated.
A metal body (anode) 5 to be plated is provided on this supporting part.
is supported and fixed so as to be located at the center of the plating solution passage 15. The cathode extraction plate 10 and the anode extraction plate 8 are insulated from each other with an electrically insulating packing 9 interposed between them.
The plating solution recovery toy 14 and the object to be plated (cathode) 6 are fixed to the cathode extraction plate 10 with bolts 19 via electrically insulating packing 13 and conductive packing 11, respectively. Ru. The open end of the plating solution recovery toy 14 faces the upper part of the plating solution recovery chamber 4 provided in the plating treatment tank 1. Furthermore, both the cathode extraction plate 10 and the body to be plated (cathode) 6 are in contact with an electrical connection member 20 . Electrically, the anode take-out plate 8 is connected to the 4 side of a plating power source (not shown), and the metal body 5 to be plated, which is supported and fixed to the anode take-out plate 8, is connected to the anode in the plating tank. Constructed as.

Further, a bolt 19 is connected to the 8 side of a plating power source (not shown), and this bolt 19, cathode extraction plate 10, and object to be plated 1
2 are electrically connected via the conductive packing 11 or the electrical connection member 20, the plated body 12 is also configured as a cathode. Note that 21 is a plating solution outflow conduit. In this method, since the anode 5 is fixed to the anode take-out plate 8, the main factor that suspends the eutectoid fine particles in the plating solution is the force due to turbulence caused by the flow velocity in the plating solution passage 15.

The force due to this turbulent flow is extremely large in the Y-axis direction in the figure when the plating solution flows from the bottom upwards compared to the flow in the X-axis direction. In other words, the velocity component ■A (vector amount) obtained by the eutectoid fine particles in the plating solution is ■1=
VAX + VAY (now VAX is the velocity component in the X-axis direction), and it is considered that ■AY > VAX, so VA + VA
It becomes Y. The velocity component that contributes to causing the eutectoid fine particles in the plating solution to collide with the plating material is AX, and the turbulent force due to the flow velocity in the plating solution passage 15 hardly contributes to the velocity VAX as described above. 0 Moreover, when the flow rate of the plating solution in the plating solution passage 15 is high, the amount of eutectoid enemy particles in the plating layer decreases;
If the flow rate in the plating solution is lowered, the suspension of the eutectoid particles in the plating solution cannot be maintained in a good state, and plating defects such as flattening, which is characteristic of composite plating, often occur.The present invention solves the above problems. In order to properly suspend the eutectoid particles in the plating solution, the anode is rotated to stir the plating solution, and centrifugal force is applied to the eutectoid particles. It is characterized by ensuring a sufficient amount of analysis.

The present invention will be explained below with reference to the conceptual diagram shown in FIG.

In FIG. 2, the anode body 30, the metal to be plated (cathode electrode) 31, the packings 32, 33, and the plating liquid passage 34 are respectively the metal body to be plated (anode electrode) 5 in FIG.
, a body to be plated (cathode electrode) 6, packings 11 and 13, and a liquid passageway 15, and the plating method according to the present invention is characterized by rotating an anode body 30 having a specific shape, which will be described later. are doing. The anode body 30 has stirring blades 30b provided on the circumferential surface of an anode rod 30a.
A specific example is shown in which stirring blades 30b are integrally formed with 0a from the same material. In the figure, (4) is the anode rod 30a
A concave portion is formed on the circumference of the anode rod 30a, and the convex portion formed by the concave portion is the stirring blade 30b. They are formed on each surface and serve as stirring blades 30b.Also (E)
(g) is a combination of an angular recess and a semicircular convex part, (G is a combination of a semicircular recess and a semicircular convex part) on the circumferential surface of the anode rod 30a. The above-mentioned stirring blades 30b are shown in FIG.
(1) shows the state in which stirring blades 30b are arranged in a straight line from the upper end to the lower end of the anode rod 30a, and (■) shows the state in which stirring blades 30b are arranged in the axial direction of the circumferential surface of the anode rod 30a, and (■) Long stirring blades 30b are arranged in a staggered manner from the upper end to the lower end of the anode rod 30a. In the plating method according to the present invention, the anode body 30 as described above is disposed in a circulation type plating treatment tank in the flow line direction of the plating solution in the plating solution passage 34, and plating is performed while rotating the anode body 30. .

Then, the eutectoid fine particles suspended in the plating solution have a velocity component V in that direction due to the centrifugal force caused by the rotation of the anode body 30.
bx is the velocity component VbY that is most dependent on the flow rate of the plating solution
The optimal value of the composite speed of the velocity component VbY and the flow velocity VbY of the plating solution, that is, the collision speed of the eutectoid fine particles with the object to be plated, is arbitrarily determined. . The plating method according to the present invention is a velocity component dependent on the flow velocity of the plating solution in the plating passageway. A centrifugal force that is controlled independently of the BY causes the eutectoid fine particles to have a velocity in a direction perpendicular to the streamline direction of the plating solution. Since the component (2) By is generated, an efficient plating action can be performed, and a composite plating film in which eutectoid fine particles are extremely well dispersed in the plating layer can be obtained.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional view of the main part showing a conventional circulation type plating device, Fig. 2 is a conceptual longitudinal sectional view of the main part for explaining the plating method according to the present invention, and Fig. 3 is the anode body. FIG. 4 is a plan view showing a portion shown in FIG. 1... Plating treatment tank, 30... Anode body, 30a... Anode rod, 30b... Stirring blade, 31... To be plated Metal (cathode electrode), 34
・・・・・・Plating liquid passage.

Claims (1)

[Claims] 1 In a circulation type plating device in which the plating solution flows in from the bottom of the plating tank and flows out from the top, an anode body with stirring blades on the surface of the anode rod is arranged in the flow direction of the plating solution in the plating tank. and a plating method characterized in that plating is performed while rotating the anode body.