JPH0751279B2 - Lead composite copper plate and its manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention is a composite plate of lead having particularly excellent weather resistance to sea salt particles, acid rain, etc. and copper having excellent corrosion resistance, such as roofs and walls. It is used for various building materials.

(Prior Art) Conventionally, there is no composite of a copper plate and a lead plate, and the copper plate and the lead plate are merely used as individual units.

(Problems to be Solved by the Invention) The most important problem in a composite material is the adhesive strength at the interface between two different materials. If the adhesive strength is weak, processing,
Not only will molding problems occur, but durability after being processed into a product cannot be guaranteed. Therefore, the present invention provides a lead composite copper plate having strong adhesion strength at the interface between the copper plate and the lead plate, which has characteristics such as weather resistance and corrosion resistance, and a method for producing the lead composite copper plate.

(Means for Solving the Problem) A first invention is one in which a nickel-based plating layer and a lead-based plating layer are sequentially provided on at least one surface of a copper plate, and the lead plate is roll-bonded to the copper plate via these plating layers. is there.

A second aspect of the present invention is the first step of performing at least one surface of nickel plating treatment and nickel-cobalt alloy plating treatment on at least one surface of a copper plate, followed by lead plating treatment and lead-tin alloy plating treatment on the plating layer. Of these, a second step of performing one plating treatment and a third step of rolling and coating a lead plate on the plating layer are performed.

(Operation) According to the above configuration, the nickel-based plating layer and the lead-based plating layer, which are the bonding mediators applied to the copper plate, are affinity bonded to the copper plate on one side, and are closely bonded to the lead plate on the other side. .

(Example) As an example of the present invention, a nickel plating process was used as the plating process in the first step, and a lead plating process was used as the plating process in the second step. Nickel-cobalt alloy plating treatment, second
The process in which the lead-tin alloy plating process is performed is described in "Example 5
8 "will be described below.

"Examples 1 to 4" A 0.4 mm copper plate was electrolytically degreased at 45 ° C and 5% sodium orthosilicate for 10 Adm ² , 2 "using the copper plate as a cathode, and then thoroughly washed with water,
After dipping and pickling in 50 ° C. hydrochloric acid-sulfuric acid, it is thoroughly washed with water and subjected to the nickel plating treatment of the following first step.

(1) First step, nickel plating NiSO ₄・ 6H ₂ O 240g / l, H ₃ BO ₃ 30g / l, NiCl ₂・ 6H ₂ O 45g /
l 、 Temperature 55 ℃ 、 Current density 5A /
The electroless nickel plating treatment is performed by setting the electrolysis time and the plating amount corresponding to the electrolysis time under dm ² as shown in Table 1 to form a nickel plating layer on one surface of the copper plate. Here, the nickel plating layer (also the nickel plating layer is the same) is required to uniformly coat the plating surface of the copper plate without leaving a minute exposed portion of the base material, but the plating amount need not be excessive. A sufficient effect was exhibited even with a plating amount of about 1.5 gm ² . Next, after sufficiently washing with water, a lead plating treatment of the following second step is performed.

(2) Second step, lead plating treatment Lead borofluoride 380 g / l, hydrofluoric acid 45 g / l, glue
Table 1 shows the electrolysis time and the plating amount corresponding to the electrolysis time at a temperature of 25 ° C and a current density of 10 A / dm ² in a bath of 0.5 gl.
Then, the lead plating layer is formed on the nickel plating layer by performing the electroplating treatment by setting as shown in FIG. The second step is not necessarily continuous with the first step, but it is desirable to use the continuous plating step as much as possible from the viewpoint of ensuring the adhesiveness of both layers. Further, the lead-based plating layer is for forming a new surface at the interface during the roll-bonding with the lead plate in the next step (third step). The required plating thickness is larger, and a plating amount of 1 g / m ² , preferably 10 g / m ² or more is suitable.

Then, after sufficiently washing with water and drying, a lead plate rolling coating treatment of the third step is performed.

(3) Third step, rolling treatment for lead plate rolling Using a two-stage cold rolling machine (roll diameter 300 mm), a cast lead plate with a thickness of 2.0 mm is cold-rolled on the lead plating layer of the copper plate to change the rolling load. By doing so, the rolling rate of the lead plate was changed to perform the roll bonding. The appropriate range of the rolling rate during rolling differs depending on the rolling force, rolling roll diameter, rolling speed, etc.The important point is that a new surface constantly appears at the interface during rolling, and a strong bond between the lead-based plating layer and the lead plate. To be born. In fact, since the lead plate is a softer material than the copper plate, the copper plate is hardly rolled and apparently sufficient adhesion is secured under the condition that only the lead plate is rolled. Calculated from the thickness and the change in the thickness of the lead layer after composite, the lead plate itself is 30%, preferably 50
Sufficient adhesion is assured if a rolling ratio of more than 100% is secured.

[Examples 5 to 8] A 0.4 mm copper plate was electrolytically degreased at 45 ° C. and 5% sodium orthosilicate for 10 A / dm ² , 2 ″ using the copper plate as a cathode, and then thoroughly washed with water and hydrochloric acid at 50 ° C. After dipping and pickling in sulfuric acid, it is thoroughly washed with water and subjected to the nickel-cobalt alloy plating treatment of the following first step.

(1) a first step, nickel - cobalt alloy plating _{NiSO 4 · 6H 2 O 240g /} l, CoSO 4 · 7H 2 O15g / l, H 3 BO 3 30g /
Table 1 shows the electrolysis time and the plating amount corresponding to the electrolysis time at a temperature of 55 ° C and a current density of 5 A / dm ² in a bath consisting of 45 g / l of NiCl ₂ · 6H ₂ O and 45 g / l of additives. The nickel-cobalt alloy plating treatment is performed by setting the above to form a nickel-cobalt alloy plating layer on one surface of the copper plate.
The cobalt content ratio in the plating layer is not particularly specified,
Even with a content ratio of only a few percent, finer crystals are formed than in the nickel-only plating layer, and the plating layer with a high cobalt ratio has better adhesion. If the interfacial bond strength required for the lead composite copper sheet to be the product is very high, the alloy plating treatment is more advantageous than the nickel single plating treatment.

Next, after sufficiently washing with water, a lead-tin alloy plating treatment of the following second step is performed.

(2) Second step, lead-tin alloy plating treatment Lead borofluoride 380 g / l tin borofluoride 30 g / l, hydrofluoric acid 45 g / l, glue 0.5 g / l in a bath consisting of a temperature of 25 ℃,
The electrolysis time and the plating amount corresponding to the electrolysis time are set under the current density of 10 A / dm ₂ as shown in Table 1 to perform the electroplating with lead-tin alloy, and the lead is deposited on the nickel-cobalt alloy plating layer. Forming a tin alloy plating layer. Regarding the content of tin in the lead-tin alloy plating layer, the adhesion with the base is improved as the tin ratio increases, and even if the content ratio is only a few percent, the lead-only plating layer In comparison with the above, finer crystals are formed, and in particular, when the rolling rate of the lead plate cannot be increased, the adhesion strength of the plating layer having a higher tin ratio is stronger.

Next, after sufficiently washing with water and drying, a lead plate rolling coating treatment of the third step is performed.

(3) Third step, lead plate rolling coating treatment Using a two-stage cold rolling mill (roll diameter 300 mm)
A cast lead plate having a thickness of 2.0 mm was cold-rolled on the tin alloy plated layer to change the rolling load of the lead plate, thereby performing the roll bonding.

As shown in the drawing, the nickel-based plating layer 2 coated on the copper plate 1 removes a stable oxide film on the copper plate, and has a good adhesion to the base material of the copper plate 1, as shown in the drawing. It becomes a plating layer, and as a result, the upper lead-based plating layer 3 firmly adheres to the copper plate 1 via the lower nickel-based plating layer 2 and also has an affinity bond with the lead plate 4 to form a copper plate and a lead plate. It is compounded with sufficient adhesive strength.

Next, Comparative Examples 1 to 3 are shown below in order to clarify the effect of the present invention.

Comparative Example 1 A copper plate was sufficiently pickled, washed with water and dried, and then both steps of the electric nickel plating treatment and the electric lead plating treatment were omitted, and a lead plate rolling coating treatment of the third step was tried. The rolling rate of the lead plate was changed by changing the rolling load.

Comparative Example 2 After the copper plate was sufficiently pickled and washed with water, only the electric nickel plating treatment was omitted, that is, only the electric lead plating treatment was applied under the plating treatment conditions of Example 1 to try the lead plate rolling coating treatment. The rolling rate of the lead plate was changed by changing the rolling load.

Comparative Example 3 A copper plate was sufficiently pickled, washed with water, and then subjected to electric nickel-cobalt alloy plating by the plating of Example 5.
Attempts were made to roll-roll the lead plate. The rolling ratio of the lead plate was changed by changing the load.

The above samples were evaluated by the following methods.

1) Peel test A composite plate having a width of 25 mm (length 150 mm) was cut out, and the adhesion between the composite layer and the copper plate was evaluated by a 180 ° peel test.

2) OT bending test OT adhesion bending was performed so that the composite layer was on the outside and the inside, and the state of peeling between the composite layer and the material was observed.

3) Salt water immersion test OT-bent test pieces were immersed in 5% saline (40 ° C) for 3 weeks, and the progress of peeling on the end faces was observed.

4) Cooling / heat cycle test A test piece of 50 × 150 mm was subjected to a repeated test up to 1500 times by immersing it in a hot silicone oil bath at 120 ° C. (5 ′) and keeping it cooled to room temperature (5 ′) as one cycle. Peeling, blistering of the lead surface, cracking of the lead layer, etc. were observed.

Table 1 shows the evaluation test results of each sample. In Table 1, ⊚ in the peel test indicates that the adhesion strength is sufficient and the lead plate itself is broken. In other OT bending tests and salt water immersion tests, ◎ indicates that no abnormality or deterioration was observed compared to before the test, Δ indicates that the lead composite layer was slightly peeled off at the processed portion such as bending, X indicates that peeling of the composite layer was recognized as sticking. ◎ in the cooling / heating cycle test indicates that no abnormality or deterioration was observed in the peeling test after applying the cooling / heating cycle, as in the initial stage, and △ indicates that the lead composite layer was slightly peeled off at the processing site such as bending. , X indicates that peeling of the composite layer was recognized as sticking.

(Effects of the Invention) The present invention is a nickel-based plating layer coated on a copper plate by roll-bonding the lead plate through a bonding mediating means consisting of a nickel-based plating layer and a lead-based plating layer covering the plating layer. Removes a stable oxide film on the copper plate to form a plating layer with good adhesion to the base material of the copper plate, and as a result, the lead-based plating layer that is the upper layer is firmly bonded to the copper plate through the nickel-based plating layer that is the lower layer. The effect of being able to industrially provide a lead composite copper plate that adheres well to the copper plate and is bonded to the copper plate in an affinity manner to combine the copper plate and the lead plate with sufficient adhesive strength to ensure stable adhesion over a long period of time. There is.

[Brief description of drawings]

The drawing is a partially enlarged sectional view of the lead composite copper plate according to the present invention. In the figure, 1 is a copper plate, 2 is a nickel plating layer, 3 is a lead plating layer, and 4 is a lead plate.

Claims (2)

[Claims] 1. A lead-composite copper plate obtained by sequentially providing a nickel-based plating layer and a lead-based plating layer on at least one surface of a copper plate, and rolling-bonding the lead plate to the copper plate through these plating layers. 2. A first step of subjecting at least one surface of a copper plate to one of nickel plating treatment and nickel-cobalt alloy plating treatment, followed by lead plating treatment and lead-tin alloy plating treatment on the plating layer. Second step of applying one plating treatment and third step of rolling and coating a lead plate on the plating layer
A method of manufacturing a lead composite copper sheet comprising steps.