JPH0533195A - Plating device for stainless steel member and plating method using this device - Google Patents

Abstract

PURPOSE:To form a plating layer having excellent adhesion and high quality on a stainless steel member without generating sparks at all at the time of power feeding since contact rollers are not used, unlike heretofore. CONSTITUTION:This plating device for the stainless steel member and the plating method using this device are disposed in series with an electrolytic degreasing cell 1 in which an electrolytic degreasing bath 1b is housed and an electrode 1a for degreasing is disposed, an electrolytic activating cell 2 in which an electrolytic activating bath 2b is housed and an electrode 2a for activating is disposed, and a plating cell 3 in which a plating bath 3b is housed and an electrode 3a for plating is disposed in this order. A power source 13 for degreasing and activating, the negative electrode 13a of which is connected to the above-mentioned electrode 1a for degreasing and the positive pole 13b of which is connected to the above-mentioned electrode 2a for activating, and a power source 14 for plating, the negative electrode 14a of which is connected to the above-mentioned electrode 1a for degreasing and the positive electrode 14b of which is connected to the electrode 3a for plating are provided. The stainless steel member 10 travels continuously in a contactless feeding state from the above-mentioned electrolytic degreasing cell 1 to the above-mentioned plating cell 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plating apparatus for stainless steel members and a plating method using the same, and more particularly to a stainless steel member which is continuously coated with a plating layer having excellent adhesion and stable quality. The present invention relates to a plating apparatus for a stainless steel member that can be formed on a steel plate and a plating method using the same.

[0002]

2. Description of the Related Art Stainless steel members are used in various fields because they have excellent corrosion resistance and mechanical strength and are relatively inexpensive. However, since a strong passivation film is formed on the surface of the stainless steel member and the electrical connectivity and solderability are inferior, the application as a material for electronic / electrical components must be restricted.

Therefore, at least a part of the surface of the stainless steel member is plated with a noble metal such as gold or silver to provide the stainless steel member with excellent corrosion resistance and mechanical strength and the plated noble metal. By utilizing both of the excellent electrical connectivity and solderability characteristics, for example, electrical contacts, connectors, switches, terminals and the like that are required to have spring properties are manufactured.

Conventionally, plating of stainless steel members is generally performed using a plating apparatus as shown in FIG. In the plating apparatus, an electrolytic degreasing tank 1, an electrolytic activation tank 2, and a plating tank 3 are arranged in this order, and further, an intermediate position between the electrolytic degreasing tank 1 and the electrolytic activation tank 2 and an intermediate position between the electrolytic activation tank 2 and the plating tank 3. Washing tanks 4, 5 and 6 are arranged at the position and on the downstream side of the plating tank 3, respectively.

The washing tank 4 has contact rollers 4a, 4
b and 4c are provided, and these are connected to the negative electrode 7a of the electrolytic degreasing power supply 7. The positive electrode 7b of the electrolytic degreasing power source 7 is connected to the degreasing electrode 1a arranged in the electrolytic degreasing tank 1. Contact rollers 5a, 5b, 5c are also arranged in the water washing tank 5, and these are connected to the negative electrode 8a of the electrolytic activation power source 8. The positive electrode 8b of the electrolytic activation power source 8 is connected to the activation electrode 2a arranged in the electrolytic activation bath 2.

Further, the contact roller 6 is also provided in the washing tank 6.
a, 6b, 6c are provided, and these are the power source 9 for plating.
Is connected to the negative electrode 9a. The positive electrode 9b of the plating power source 9 is connected to the plating electrode 3a arranged in the plating tank 3. All of the above contact rollers are for contacting the surface of the stainless steel member to supply the current supplied from each power source to the stainless steel member.
It is made of an i-based alloy.

An uncoiler 1 around which a stainless steel member 10 such as a strip is wound is provided on the upstream side of the electrolytic degreasing tank 1.
1 is arranged, and a coiler 12 for winding the stainless steel member 10 is arranged on the downstream side of the washing tank 6. In the plating process, first, the electrolytic degreasing tank 1 contains a predetermined electrolytic degreasing bath 1b, the electrolytic activation tank 2 contains a predetermined electrolytic active bath 2b, and the plating tank 3 contains a predetermined plating bath 3b. Then, the stainless steel member 10 is unwound from the uncoiler 11 and continuously made to run in the apparatus from the electrolytic degreasing tank 1 to the plating tank 3 with the stainless steel member 10 being in contact with the contact rollers of each washing tank, and finally the coiler 12 is used. Wind up.

Then, in this process, a current having a predetermined value is supplied from each of the power supplies 7, 8 and 9. In the electrolytic degreasing tank 1, cathodic electrolysis occurs between the stainless steel member 10 and the degreasing electrode 1a, and as a result, oil and dirt attached to the surface of the stainless steel member 10 are physically generated by a large amount of generated gas. The stainless steel member 10 is washed in the water washing tank 4 and then moved to the next electrolytic activation tank 2.

In the electrolytic activation tank 2, cathodic electrolysis occurs between the activating electrode 2a and the stainless steel member 10, and as a result, the passive film (oxide) on the surface of the stainless steel member 10 is reduced and the surface thereof is reduced. Activate. Then, after the stainless steel member 10 is washed in the washing tank 5, it travels to the next plating tank 3. The above process has a position as a pretreatment prior to the substantial plating on the stainless steel member.

Here, the electrolytic degreasing treatment is usually carried out in an electrolytic degreasing bath 1b at a bath temperature of about 50.degree.
The conditions are as follows: an alkaline aqueous solution having a concentration of about 100 g / l, a current density of 1 to 5 A / dm ² , and a treatment time of 0.5 to 5 minutes. The conditions for the electrolytic activation treatment are usually as follows: Electrolytic activation bath 2b, bath temperature: about 40 ° C., H
Cl concentration: 15% acid aqueous solution, current density: 1-5
A / dm ² , processing time: 0.5 to 5 minutes are used.

After such pretreatment, in the plating tank 3, the activated surface of the stainless steel member 10 is subjected to predetermined electrolytic plating, and the plated stainless steel member 10 is washed in the washing tank 6. After being done, it is wound up by the coiler 12.

[0012]

By the way, in the above-mentioned conventional plating apparatus, power is supplied to the stainless steel member through a contact roller (power supply roller) which is in contact with the stainless steel member. However, since the contact resistance between the stainless steel member and the contact roller is large, sparks may occur from the contact point between the two when the power is supplied. Then, when the spark is generated, the spot where the spark is generated in the stainless steel member becomes a surface defect. As a result, the surface appearance of the finally obtained plated member is inferior, or the adhesion of the plating is deteriorated, causing problems such as peeling of the plated layer. This spark frequently occurs when the power is supplied at a high current density.

In order to solve such a problem, conventionally, the contact roller is made of a material in which a precious metal such as gold or silver is plated on the surface of an Fe-Ni alloy,
Alternatively, measures have been taken to reduce the energizing current to supply power. However, in the case of the former measure, although the contact resistance with the stainless steel member is reduced and the occurrence frequency of sparks is reduced, however, the sparks cannot be completely prevented. In the case of the latter measure, although the generation of sparks is suppressed, the pretreatment becomes insufficient, so the adhesion between the plating layer formed in the plating tank and the stainless steel member decreases, and the plating layer Frequently peeling off occurs. That is, it becomes difficult to stably form a high quality plating layer.

The present invention solves the above-mentioned problems and pretreatment or plating of a stainless steel member can be performed without using a contact roller, so that no spark is generated at the time of power feeding, and therefore the adhesion is excellent. It is an object of the present invention to provide a plating apparatus for a stainless steel member capable of performing excellent plating and a plating method using the same.

[0015]

To achieve the above object, in the present invention, an electrolytic degreasing bath is accommodated, and an electrolytic degreasing bath in which a degreasing electrode is disposed and an electrolytic activation bath are accommodated. , An electrolytic activation bath in which an activation electrode is disposed and a plating bath in which a plating bath is accommodated and in which a plating electrode is disposed are arranged in series in this order, and the negative electrode is the degreasing electrode. A degreasing / activating power source which is connected and whose positive electrode is connected to the activation electrode; and a plating power source whose negative electrode is connected to the degreasing electrode and whose positive electrode is connected to the plating electrode. Provided is a plating apparatus for a stainless steel member, characterized in that the stainless steel member continuously runs in a contactless power supply state from the electrolytic degreasing tank to the plating tank. The material is continuously run from the electrolytic degreasing tank to the plating tank, the surface of the stainless steel member is degreased by anode electrolysis in the electrolytic degreasing tank, and then the surface of the stainless steel member by cathode electrolysis in the electrolytic activation tank. Activate it, and finally,
There is provided a method for plating a stainless steel member, characterized in that electrolytic plating is performed in the plating bath.

The basic structure of the plating apparatus of the present invention is shown in FIG. In the figure, an electrolytic degreasing tank 1, a water washing tank 4, an electrolytic activation tank 2, a water washing tank 5, a plating tank 3, and a water washing tank 6 are arranged in series in this order. The electrolytic degreasing tank 1 has a degreasing electrode 1a and an electrolytic activity. An activating electrode 2a is arranged in the tank 2, a plating electrode 3a is arranged in the plating tank 3, an uncoiler 11 is arranged upstream of the electrolytic degreasing tank 1, and a coiler 12 is arranged downstream of the washing tank 6. Uncoiler 11 to coiler 1
The fact that the stainless steel member 10 continuously travels in each tank up to 2 is no different from the case of the conventional apparatus of FIG.

However, in the case of the device of the present invention, unlike the case of the conventional device shown in FIG. 2, first, the contact rollers are not present in the washing tanks 4, 5 and 6. Further, the negative electrode 13a of the power source 13 and the degreasing electrode 1a of the electrolytic degreasing tank are connected,
Further, by connecting the positive electrode 13b and the activation electrode 2a of the electrolytic activation tank, a power supply circuit composed of the positive electrode 13b of the power source 13-the activation electrode 2a-the stainless steel member 10-the degreasing electrode 1a-the negative electrode 13a of the power source 13. Are formed.

Therefore, the power source 13 functions as a degreasing / activating electrode capable of supplying power to both the electrolytic degreasing tank 1 and the electrolytic activation tank 2. Further, the power source 14 connects the negative electrode 14a and the degreasing electrode 1a of the electrolytic degreasing tank,
Further, by connecting the positive electrode 14b and the plating electrode 3a of the plating bath, the positive electrode 14b of the power source 14-the plating electrode 3a-the stainless steel member 10-the degreasing electrode 1a-.
A power supply circuit including the negative electrode 14a of the power supply 14 is formed.

Therefore, the power source 14 functions as a power source for electrolytic degreasing and plating, but mainly functions as a power source for plating. In the apparatus of the present invention, the stainless steel member 10 unwound from the uncoiler 11 continuously travels without contacting the contact rollers during the entire process until it is wound up by the coiler 12. Therefore, no spark that causes a surface defect of the stainless steel member 10 is generated. Therefore, unlike the case of the conventional device, it becomes possible to energize at a high current density without worrying about the occurrence of sparks.

During the traveling process of the stainless steel member 10, in the electrolytic degreasing tank 1, anode electrolysis occurs between the stainless steel member 10 and the degreasing electrode 1a. As a result, the generated gas cleans the surface of the stainless steel member 10. Then, in the electrolytic activation tank 2, the stainless steel member 1
Cathodic electrolysis occurs between 0 and the activation electrode 2a. As a result, the surface of the stainless steel member 10 is activated.

At this time, it is preferable to use an electrode made of stainless steel which is a soluble electrode as the activation electrode 2a. At the same time as activating the stainless steel member 10, the components such as Cr and Ni of the stainless steel electrode are
This is because they are deposited on the surface of the stainless steel member 10, and as a result, the adhesion of the plated layer formed can be improved compared to the case where an insoluble electrode such as iron is used.

In this pretreatment process, since the stainless steel member is running in a completely non-contact power supply state, the electrolytic degreasing treatment and the electrolytic activation treatment should be performed at a high current density without worrying about the occurrence of sparks. You can Therefore, since the surface of the stainless steel member can be sufficiently cleaned and activated, the adhesion of the plating layer formed in the plating tank 3 becomes excellent.

Further, since the plating in the plating tank 3 is also performed in a non-contact power supply state, there is no fear of sparking due to contact with a contact roller as in the conventional case.
It can be plated at a suitable current density. Further, in the present invention, the stainless steel member 10 is the electrolytic degreasing tank 1,
When passing through the electrolytic activation bath 2 and the plating bath 3, the traveling always runs in the same direction, and the route does not bend due to rollers etc. as is conventionally done in some parts, so the traveling stainless steel member Will not be deformed by these rollers or the surface will not be scratched, and it becomes possible to manufacture a plated material having excellent surface quality.

In the present invention, it is also possible to perform non-contact power supply only in the above-mentioned pretreatment step and supply power using a power supply roll in the plating tank as in the conventional case.

[0025]

EXAMPLE In the apparatus of FIG. 1, electrodes 1a, 2a, 3a
As the electrodes of the materials shown in Table 1,
An electrolytic degreasing bath 1b having an H concentration of 10% and a bath temperature of 50 ° C., an electrolytic active bath 2b having an HCl concentration of 15% and a bath temperature of 30 ° C. were used. As the plating bath 3b, in the case of Ni plating, the composition: nickel sulfate 250 g / 1, boric acid 30g / l, nickel chloride 3
In the case of 0 g / l, Ag plating, composition: silver cyanide 50
g / l, potassium cyanide 50 g / l, potassium carbonate 3
0 g / l, in the case of Au plating, composition: potassium gold cyanide 10 g / l, potassium cyanide 30 g / l, potassium carbonate 30 g / l, dibasic potassium phosphate 30 g / l, thickness 0.06 mm, width 100 mm SUS301 strip 1
No. 0 was plated with Ni, Ag, and Au.

Power supply and power supply from the degreasing / activation power supply 13
Pretreatment was performed by changing the time as shown in Table 1, and N
In the case of i plating, the current density from the plating power supply 14 is 3 A
/ Dm ²Power supply for 5 minutes, current density 1 for Ag plating
A / dm²Power supply for 5 minutes, current density in case of Au plating
0.5 A / dm²Power is supplied for 10 minutes, and each has a thickness of 3μ
m Ni plating, Ag plating, and Au plating were performed.

For comparison, the conventional apparatus shown in FIG. 2 was used to perform the pretreatment at the current densities shown in Table 1 for the indicated time, and then Ni plating, Ag plating, and Au plating was applied. The contact rolls in this conventional apparatus are all made of Fe-Ni alloy. Observe the surface of each obtained plated strip with a microscope,
The spark generation amount was calculated by measuring the spark scratches existing per 1 m of the strip material.

After heating each plated strip for 30 minutes in the air at 400 ° C., a cross-cut test was conducted on its surface to examine the adhesion of the plated layer. No peeling (excellent adhesion): ○, slightly peeled (adhesiveness good): △, a lot of peeling (poor adhesion): evaluated as ×. The above results are collectively shown in Table 1.

[0029]

[Table 1]

[0030]

As is clear from the results shown in Table 1, since the apparatus of the present invention does not use a contact roller,
No spark is generated when power is supplied. therefore,
In the pretreatment stage, power can be supplied at a high current density to perform sufficient electrolytic degreasing and electrolytic activation, so the plating layer formed on the surface of the stainless steel member has excellent adhesion and at the same time a good quality plating layer. become.

Further, since the contact roller is not required and the power source is reduced by one series as compared with the case of the conventional apparatus, the equipment cost of the apparatus is also low and its industrial value is great.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a basic configuration of a device of the present invention.

FIG. 2 is a schematic diagram showing a basic configuration of an example of a conventional device.

[Explanation of symbols]

1 Electrolytic degreasing tank 1a Degreasing electrode 1b Electrolytic degreasing bath 2 Electrolytic activation tank 2a Active electrode 2b Electrolytic activation bath 3 plating tank 3a Electrode for plating 3b Plating bath 4 water washing tank 4a, 4b, 4c Contact roller 5 water washing tank 5a, 5b, 5c Contact roller 6 water washing tank 6a, 6b, 6c Contact roller 7 Power source for electrolytic degreasing 7a Negative electrode of power supply 7 7b Positive electrode of power supply 7 8 Power supply for electrolysis activation 8a Negative electrode of power supply 8 8b Positive electrode of power supply 8 9 Power supply for plating 9a Negative electrode of power supply 9 9b Positive electrode of power supply 9 10 Stainless steel parts 11 Uncoiler 12 coilers 13 Degreasing and activation power supply 13a Negative electrode of power supply 13 13b Positive electrode of power supply 13 14 Power supply for plating 14a Negative electrode of power supply 14 14b Positive electrode of power supply 14

Claims (3)

[Claims] 1. An electrolytic degreasing bath containing an electrolytic degreasing bath and an electrode for degreasing, an electrolytic activating bath containing an electrolytic activating bath and having an activating electrode, and a plating bath. A degreasing / activator in which a plating tank in which a plating electrode is housed is arranged in series in this order, the negative electrode is connected to the degreasing electrode, and the positive electrode is connected to the activation electrode. Power source and a plating power source, the negative electrode of which is connected to the degreasing electrode and the positive electrode of which is connected to the plating electrode, and stainless steel in a non-contact power supply state from the electrolytic degreasing tank to the plating tank. A plating device for stainless steel members, wherein the members continuously run. 2. The plating apparatus according to claim 1, wherein the stainless steel member is continuously run from the electrolytic degreasing tank to the plating tank, and the surface of the stainless steel member is degreased by anode electrolysis in the electrolytic degreasing tank. Then,
A method for plating a stainless steel member, characterized in that surface activation of a stainless steel member is performed by cathode electrolysis in the electrolytic activation tank, and finally electrolytic plating is performed in the plating tank. 3. A stainless steel member is run in a non-contact power supply state in the electrolytic degreasing tank and the electrolytic activation tank,
The method for plating a stainless steel member according to claim 2, wherein the stainless steel member is caused to travel in contact with a power feeding roller in the plating tank.