JPH0311876B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a method for manufacturing a copper composite steel sheet that has excellent corrosion resistance, especially outdoor weather resistance, and the copper composite steel sheet can be used stably over a long period of time as various building materials. It is something. (Conventional technology) Copper plates have been used for many years as roofing materials, wall materials, etc., but in order to use copper plates alone, it is usually about 0.2
Because it requires a thickness of more than mm, it is a fairly expensive material, and because the material itself is hard, it requires special skill and ingenuity in the processing method. Copper-plated steel sheets were proposed for this purpose, but in a normal corrosive environment, if a flaw occurs that reaches the base material during construction or use, the plating layer does not have a sacrificial anode effect, but rather pores in the base material. There was a defect that promoted eating. This problem can be considerably improved by using a stainless steel plate as the substrate, but it does not solve the problem of being easily scratched.In this respect, it would be better to make the plating layer thicker, but it would reduce the productivity of the plating line. As a result, an effective solution cannot be reached. As described above, the copper-based materials conventionally used as roofing materials and wall materials each have their own drawbacks, and there is a need for a material that is cheaper, easier to construct, and has higher quality reliability. (Problems to be Solved by the Invention) In view of the above, the present invention seeks to provide a method for manufacturing a copper composite steel sheet as a material that is cheaper than a copper sheet, has a longer life than a copper-plated steel sheet, and is easier to construct. (Means for Solving the Problems) The present invention comprises a first step of applying nickel plating to at least one surface of a base steel plate, a second step of applying copper plating on the nickel plating layer, and a second step of applying nickel plating to the nickel plating layer. This is a method for producing a copper composite steel plate by a third step of rolling and coating a copper plate on the layer. Here, base steel sheets include stainless steel sheets, ordinary steel sheets, (hot-rolled steel sheets,
At least one side of cold-rolled steel sheets or other materials is coated with a known plating layer such as aluminum plating, zinc plating, chrome plating, tin plating, zinc-aluminum alloy plating, iron-zinc alloy plating, etc. It also includes steel sheets coated by melting or electroplating. In addition,
When the base steel sheet is a regular steel sheet, a copper plating layer with better adhesion can be obtained compared to a stainless steel sheet.
The nickel plating layer, which serves as a base, is not always necessary in some cases. Furthermore, in the case of a single-sided plated ordinary steel plate, the non-plated surface is used as the composite treated surface. (Function) A copper plating layer with good adhesion can be obtained on the base steel plate through the nickel plating layer, and the copper plating layer forms a new surface with the copper plate that is rolled and composited on top of the copper plate to strengthen the copper plate. to be joined to. (Example) To describe the specific means of the present invention below, when the base steel plate is a stainless steel plate, first, the plating surface is degreased by cathodic electrolysis treatment in caustic soda or sodium orthosilicate solution, and after washing with water, Usually, cathodic electrolytic pickling is applied, but for stainless steel plates, ferrite type or austenite type, especially Cr, Ni,
Pickling resistance may vary depending on the content of Si, Mo, C, etc. The surface of the steel plate, whose water wettability has been ensured by pickling, is sufficiently washed with water so that no residue of the pickling solution remains attached, and then electroplated with nickel. The role of this lower plating layer is to ensure sufficient adhesion between the subsequently processed upper copper plating layer and the base steel sheet. Therefore, the nickel plating layer needs to cover the surface of the steel plate uniformly so that no minute exposed portions of the base material remain, but there is no need to apply an excessive amount of plating. In the case of stainless steel plates, a sufficient effect was achieved with a plating amount of about 1.5 g/m ² . In addition, if copper plating is directly applied to the surface of a steel sheet without applying a nickel plating layer, it is not clear before the copper is composited, but the appropriate rolling rate range for the copper plate when composited with copper is narrow, and rolling rate management is required. strictly,
It becomes necessary to carry out the process at a higher rolling reduction rate. That is,
This is disadvantageous in terms of manufacturing conditions, and in addition, the adhesion between the copper layer and the substrate after copper composite is weak, especially when the rolling reduction rate when rolling bonding to copper is low (especially noticeable when the initial reduction is less than 35%). ), the copper layer may peel off from the edge of the cut part, or the copper layer may peel off from the end surface of the cut part, or after the bending test, it may be soaked in 5% saline solution for 10 minutes at room temperature.
If the copper layer is left immersed for several days, deterioration of the adhesion between the copper layer and the substrate is easily observed. The mechanism of action of the nickel plating layer is not clear, but
It removes the stable oxide film on the stainless steel plate to create a plating layer with good adhesion to the base, and is extremely effective in making the above-mentioned upper copper plating layer firmly adhere to the base. . As is clear from its purpose, it is sufficient to apply nickel plating to one side, and this purpose is easily achieved if no anode is placed on the non-plated side during electrolytic treatment. The nickel-plated steel sheet is then copper-plated. The nickel plating process and the copper plating process do not necessarily have to be continuous. From the viewpoint of adhesion between both layers, it is preferable to perform the plating process as continuously as possible. If the plating process cannot be continuous for unavoidable reasons, the plating process should be performed on the nickel-plated surface immediately before copper plating. Wet brushing or light pickling with dilute hydrochloric acid is effective. The role of the copper plating layer is to maintain adhesion between the copper composite layer and the nickel-plated base steel sheet, so it is important that the underlying nickel-plated surface is uniformly covered with the copper plating layer. points are secured, and
The amount of plating should be sufficient to generate a new surface at the interface when rolled and joined to the copper plate, preferably 10 g/m ²
The above plating amount is appropriate. Next, a copper plate (including a coil shape) is cold rolled and bonded to the layer surface of the copper plating layer. It is important that there is no dirt on the surface of the plated base steel plate or copper plate that would inhibit good adhesion between the two materials, and that there is no chemically stable oxide film on the copper plate. If there is a possibility that adhesion inhibiting factors remain, remove them by physical means (for example, Scotch brite polishing or scraping with a wire brush).
In addition, during cold rolling, it is important to select the optimum cold rolling rate that constantly creates a new surface at the bonding interface between the copper plate and the copper plating layer, depending on the rolling force, rolling roll diameter, rolling speed, etc. That's true. The present invention will be specifically explained based on examples.
Stainless steel plate with a thickness of 0.4 mm (SUS304, plate width 200
mm) was electrolytically degreased in a 5% sodium silicate solution at 45°C using the steel plate as a cathode, and then thoroughly washed with water.
Then, after electrolytic pickling in a 15% sulfuric acid solution at 55°C,
After thorough washing with water, a sample of a copper composite steel plate was obtained by electrolytic nickel plating, electrolytic copper plating, and rolling bonding of the copper plate according to the following steps. (1) In a plating bath consisting of 240 g of nickel chloride and 100 g of hydrochloric acid, at a temperature of 40°C and a current density of
The plating amount was confirmed at 10 A/dm ² and the nickel plating time was selected as shown in Table 1. (2) After thoroughly washing the plated layer surface of the above nickel plating with water, place it in a bath consisting of 300 g of copper sulfate, 100 g of sulfuric acid, and 30 g of ammonia sulfate at a temperature of 25°C.
The current density is 20A/ ^dm2 , and the copper plating time is shown in Table 1.
As shown in Examples 1 to 9, the amount of plating was adjusted and confirmed, thoroughly washed with water, and then dried to obtain a steel plate for copper composite. (3) Two-high cold rolling mill (work roll diameter is upper roll
80mmφ, lower roll 300mmφ, copper plate in contact with upper roll), roll a 1.0mm thick copper plate onto a stainless steel plate with copper plating on the upper layer.
Cold rolled and joined at 20.0 tons/10mm. In the table, ratio -1 refers to Comparative Example 1, in which both nickel plating and copper plating were omitted, that is, only pickling was performed, and a rolling load of 20.0 tons/10 mm copper composite was attempted. Ratio-2 is the one in which nickel plating is omitted, that is, only copper plating is applied, and then copper composite is applied at a rolling load of 20.0 tons/10 mm. Ratio-3 is one in which only nickel plating is applied, copper plating is omitted, and copper composite is applied at a rolling load of 10.0 tons/10 mm. The following evaluation tests were conducted for each sample of the following copper composite steel sheets. (1) Peeling test The sample with a width of 25 mm was cut out, and the adhesion between the composite layer and the steel plate was evaluated using a 180° peeling test. (2) Adhesive bending test Adhesive bending was performed so that the composite layer was on the outside and inside, and the peeling situation between the composite layer and the base steel plate was observed. (3) Salt water immersion test The closely bent test piece was immersed in 5% salt water (40
℃) for 3 weeks, and the progress of peeling at the end face was observed. (4) Cold-thermal cycle test A cold-thermal cycle test in which a 50 x 150 mm test piece is immersed in a hot silicone oil bath at 120°C for 5 minutes, then cooled to room temperature (by blowing cold air with a blower) and held for 5 minutes.
The test was repeated 1500 times, and peeling at the end face, blistering on the copper surface, and cracking on the copper layer were observed. Table 1 shows the above samples and the test results for the samples. In Table 1, ◎ in the peel test indicates that the adhesion strength is sufficient and the copper plate itself breaks. In other contact bending tests and salt water immersion tests, ◎ indicates that no abnormality or deterioration is observed compared to before the test. △ indicates that the copper composite layer has slightly peeled off at the processed parts such as bending. × indicates that peeling of the composite layer was clearly observed. ◎ in the cooling/heating cycle test means that no abnormality or deterioration is observed in the peeling test after applying the cooling/heating cycle, as in the initial stage. △ means that the copper composite layer has slightly peeled off at the bending and other processing parts. × indicates that peeling of the composite layer is clearly recognized, and ○ in the peel test, adhesion bending test, and cooling/heating cycle indicates that there is almost no abnormality. (Effects of the Invention) As described above, according to the present invention, as is clear from the test results, not only a durable material (copper composite steel plate) with excellent corrosion resistance and weather resistance is provided, but also a copper material and a steel plate. It has the characteristics of providing a luxurious feel and easy construction by combining the characteristics of

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Claims (1)

[Scope of Claims] 1. A first step of applying nickel plating to at least one side of a base steel sheet, a second step of applying copper plating on the nickel plating layer, and a step of applying a copper plate on the copper plating layer. A method for producing a copper composite steel sheet comprising a third step of rolling coating. 2. Claim 1, wherein the base steel plate is made of stainless steel plate.
The method for producing the copper composite steel sheet described above.