JPH0788599B2 - Method for producing iron-coated composite material - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an iron-coated composite material, and more particularly to a method for manufacturing an iron-coated composite material having a malleable and soft electrodeposited iron plating layer.

[0002]

2. Description of the Related Art As a method for producing a metal-coated composite material, an electrodeposition plating method for forming a metal coating layer on the surface of a core material by electroplating, a vacuum deposition method for coating a metal layer on the surface of the core material by metal deposition, and a core Known are the clad method of inserting the material into the outer metal tube and subjecting it to a drawing process to form a metal coating layer, and the hot dip coating method of running the core material into the molten metal and coating the surface of the core material with the molten metal. Has been.

However, the electrodeposition plating method is mainly used as a method for producing the iron-coated composite material. The reason is,
In the vacuum deposition method, the vapor pressure of iron is low, so it is difficult to deposit by industrial means.In the clad method, it is difficult to obtain a high-purity iron tube of the desired size to be used as a cladding tube from the market, and even if it can be obtained, it is very In addition to being expensive, there is a problem in terms of economic efficiency to industrially adopt such as poor yield because the joining between the core metal which is a dissimilar metal cannot be sufficiently obtained in the drawing process, In the hot dipping method, since the melting point of iron is as high as 1535 ° C., the metal material that can be used as the core material is limited.

However, the electrodeposited iron-plated layer of the iron-coated composite material obtained by the conventional electrodeposition-plating method has no malleability and toughness, is difficult to plastically work, and is subject to strong bending deformation. There is a defect that cracks occur when it is played.
Therefore, in order to obtain an iron-coated composite material of a desired size, the core material is rolled to a predetermined size in advance, plastic working such as wire drawing is performed, and then this core material is subjected to an iron electrodeposition plating step. There is.

[0005]

However, when the core material becomes thin, especially when the material has low mechanical strength,
A lot of breakage troubles occur in the electrodeposition plating process, which is a win. For example, an iron-plated enamel copper wire obtained by electrodepositing a ferromagnetic iron on a thin core wire of a non-magnetic conductor such as copper or a copper alloy is used as a wire material for a high-frequency coil because it has excellent high-frequency characteristics. In the case of such a thin core wire, disconnection trouble is likely to occur due to mechanical tension applied in the electrodeposition plating step, which is a cause of markedly reducing productivity.

Particularly, in recent years, in order to reduce the size of the coil, when the outer diameter of the core wire is reduced to 30 to 25 microns, the core wire is often unable to withstand the mechanical tension in the electrodeposition plating step and is often broken. Therefore, manufacturing is difficult.

The present invention has been made in order to solve the above-mentioned problems, and can be easily processed to a predetermined size by plastic working such as rolling and wire drawing, and electrodeposition iron plating by bending. It is an object of the present invention to provide a method for producing an iron-coated composite material having excellent mechanical properties which does not cause cracks in the layer.

[0008]

According to the present invention, a plastically workable metal core material is immersed in an acidic iron salt aqueous solution, high purity electrolytic iron having a purity of 99.9% or more is used as an anode, and a bath temperature is set to 40. ℃
Above and current density of 0.3 A / dm ² or above 0.5 A
Characterized in that the iron plated layer is electrodeposited on the outer periphery of the metal core material by applying a current at a low current density of / dm ² or less, hot or cold plastic working, and working to a predetermined size. A method for producing an iron-coated composite material is provided.

In the above structure, it is preferable to use ferrous sulfate as the main component of the acidic iron salt aqueous solution.

[0010]

In the method of manufacturing an iron-coated composite material according to the present invention, a plastically workable metal core material is immersed in an acidic iron salt aqueous solution, and electroplating is performed under the following conditions. High-purity electrolytic iron having a purity of 99.9% or more is used for the anode. A bath temperature of 40 ° C or higher and a current density of 0.3 A /
It is set to a low current density of dm ^{2 to} 0.5 A / dm ² . By this electroplating, the purity of 99.
97% or more, carbon content 20ppm or more 150ppm
Hereinafter, it is possible to form a tough and soft electrodeposited iron plating layer having a composition having an oxygen content of 40 ppm or less, a Vickers hardness of 250 or less, little internal stress, and ductility.
As a result, an iron-coated composite material having excellent plastic workability can be obtained.

On the other hand, the anode has a purity of 99.9%.
If the above high-purity electrolytic iron is not used, the co-deposition of impurities during plating will occur. The eutectoid of this impurity refines the crystal in order to activate the generation of plating crystal nuclei, but when the crystal is refined, the grain boundary becomes large, and the crystal lattice plane (face-centered cubic lattice type iron, The slip deformation on the (110) plane stops at the grain boundaries, and the plastic workability becomes extremely poor.
Further, since the impurities co-deposit on the grain boundaries, the mechanical properties are deteriorated, and cracks occur in the electrodeposited iron plating layer during plastic working such as rolling and drawing. That is, a sound iron-coated composite material cannot be obtained.

When the plating bath temperature is lower than 40 ° C. or the current density is less than 0.3 A / dm ² ,
Plating efficiency is extremely deteriorated. On the other hand, the current density is 0.5
When the current density is higher than A / dm ² , the overvoltage of plating deposition becomes large, the generation of plating crystal nuclei becomes active, the plating crystals become finer, and the plastic workability becomes extremely poor as described above. . Further, hydrogen is likely to be generated in the plating solution, many crystal nucleus generation points are generated, and the crystal is also finely divided, so that the plastic workability is remarkably deteriorated as described above.

[0013]

EXAMPLE FIG. 1 shows a process flow chart of an example of a method for producing an iron-coated composite material according to the present invention. The core material 1 is, for example, a metal rod material or a wire material having a circular or rectangular cross section.

The electrodeposition iron plating apparatus 2 comprises a hydrochloric acid bath, a sulfuric acid bath or a mixed bath thereof, and the anode has a purity of 9%.
High-purity electrolytic iron of 9.9% or more is used. Electrolysis parameters such as component concentration of the electrolytic solution, bath temperature, and current density are determined in consideration of the material, structure, plating thickness, etc. of the core material 1. However, the purity is 99.97% or more, the content carbon content is 20 ppm or more and 150 ppm or less, the content oxygen content has a composition of 40 ppm or less, in order to form an electrodeposition iron plating layer of Vickers hardness 250 or less, It is necessary to set the bath temperature to 40 ° C. or higher and the current density to a low current density of 0.3 A / dm ^{2 to} 0.5 A / dm ² . A batch type or a continuous type is selected in consideration of the shape of the core material 1. A flexible iron-coated composite base material 3 is obtained from the electrodeposition iron plating device 2.

The extrusion device, rolling device or drawing device 4 is
The flexible iron-coated composite base material 3 is subjected to plastic working. Extrusion, rolling and wire drawing are selected depending on the shape and size of the flexible iron-coated composite base material 3. When the diameter is relatively large, wire drawing is performed after extrusion or rolling. If the diameter is relatively small, draw directly. The flexible iron-coated composite material 5 processed into a predetermined size is obtained from the extrusion device, the rolling device or the wire drawing device 4.

FIGS. 2 (a), (b) and (c) show an example of the flexible iron-coated composite material 5, in each of which 6 is an electrodeposited iron plating layer.

-Production Example 1-A copper material having an outer diameter of 8 mmφ was used as the core material. As pretreatment, cathode degreasing in sodium hydroxide-based alkaline solution (treatment condition; liquid temperature 50 ° C, cathode voltage DC4V, treatment time 3 minutes), washing with water and pickling in hydrochloric acid-based solution Scale and oxide removal and water washing were performed.

After the pretreatment, a 0.4 mm thick electrodeposited iron plating layer was formed under the following conditions. The conditions are: plating solution; FeCl ₂ .4H ₂ O 300 g / l CaCl ₂ .2H ₂ O 200 to 400 g / l pH 1-2 bath temperature; 60 ° C. plating solution circulation flow rate; 5 to 10 l / min anode; high purity Electrolytic iron (purity 99.9%) Current density: 0.5 A / dm ² .

The composition of the electrodeposited iron plating layer has a purity of 99.97.
% Or more, carbon content 20 ppm or more and 150 ppm or less,
It was confirmed by component analysis that the oxygen content was 40 ppm or less. The Vickers hardness was 115.

The obtained iron-coated copper material could be made into a flexible iron-coated composite wire of 0.06 mmφ by cold drawing without intermediate annealing. No abnormalities such as cracks were found in the electrodeposited iron plating layer. Further, by adding the intermediate annealing, a flexible iron-coated composite wire of 0.02 mmφ could be obtained. No abnormalities such as cracks were found in the electrodeposited iron plating layer.

-Production Example 2-A copper material having an outer diameter of 8 mmφ was used as the core material. As pretreatment, cathode degreasing in sodium hydroxide-based alkaline solution (treatment condition; liquid temperature 50 ° C, cathode voltage DC4V, treatment time 3 minutes), washing with water and pickling in hydrochloric acid-based solution Scale and oxide removal and water washing were performed.

After the pretreatment, an electroplated iron plating layer having a thickness of 0.4 mm was formed under the following conditions. The conditions are as follows: plating solution; FeSO ₄ + 7H ₂ O 150 g / l (NH ₄ ) ₂ SO ₄ 150 g / l pH 2-3 bath temperature; 50 ° C. circulation flow rate of plating solution; 5-10 l / min anode; high-purity electrolytic iron ( Purity 99.9%) Current density: 0.3 A / dm ² .

The composition of the electrodeposited iron plating layer has a purity of 99.97.
% Or more, carbon content 20 ppm or more and 150 ppm or less,
It was confirmed by component analysis that the oxygen content was 40 ppm or less. The Vickers hardness was 112.

The obtained iron-coated copper material could be made into a flexible iron-coated composite wire of 0.1 mmφ by cold drawing without intermediate annealing. No abnormalities such as cracks were found in the electrodeposited iron plating layer. Further, by adding the intermediate annealing, a flexible iron-coated composite wire of 0.02 mmφ could be obtained. No abnormalities such as cracks were found in the electrodeposited iron plating layer.

-Production Example 3-A copper material having an outer diameter of 8 mmφ was used as the core material. As pretreatment, cathode degreasing in sodium hydroxide-based alkaline solution (treatment condition; liquid temperature 50 ° C, cathode voltage DC4V, treatment time 3 minutes), washing with water and pickling in hydrochloric acid-based solution Scale and oxide removal and water washing were performed.

After the pretreatment, a 0.4 mm thick electrodeposited iron plating layer was formed under the following conditions. Conditions, the plating _{solution: FeSO 4 · 7H 2 O 250g} / l FeCl 2 · 4H 2 O 40g / l NH 4 Cl 20g / l pH 2~3 bath temperature; at 5 to 10 L / min; 40 ° C. plating solution circulation flow rate is there.

The composition of the electrodeposited iron plating layer has a purity of 99.97.
% Or more, carbon content 20 ppm or more and 150 ppm or less,
It was confirmed by component analysis that the oxygen content was 40 ppm or less. The Vickers hardness was 124.

The obtained iron-coated copper material could be made into a flexible iron-coated composite wire of 0.1 mmφ by cold drawing without intermediate annealing. No abnormalities such as cracks were found in the electrodeposited iron plating layer. Further, by adding the intermediate annealing, a flexible iron-coated composite wire of 0.02 mmφ could be obtained. No abnormalities such as cracks were found in the electrodeposited iron plating layer.

[0029]

According to the method for producing an iron-coated composite material of the present invention, an iron-coated composite material having a plastically workable electrodeposited iron plating layer can be suitably obtained. Therefore, an ultrafine iron-coated composite material, which has been difficult to obtain until now, can be obtained. As a result, the applications of the iron-coated composite material can be expanded, and electronic parts and the like using the iron-coated composite material can be made smaller and have higher performance and lower costs.

[Brief description of drawings]

FIG. 1 is a process flow chart of an embodiment of a method for manufacturing an iron-coated composite material according to the present invention.

2 (a), (b), (c) are cross-sectional views of an iron-coated composite material, respectively.

[Explanation of symbols]

 1 Core Material 2 Electroplated Iron Plating Equipment 3 Flexible Iron Coated Composite Base Material 4 Extrusion, Rolling, Drawing Equipment 5 Flexible Iron Coated Composite Material 6 Electroplated Iron Plating Layer

Claims (1)

[Claims] 1. A high-purity electrode having a purity of 99.9% or more is immersed in an anode by immersing a plastically workable metal core material in an acidic iron salt aqueous solution.
The temperature of the bath, which is the main factor of electrolysis parameters, is 40
℃ or more and current density of 0.3 A / dm ² or more 0.5
A low current density of A / dm ² or less is set and electricity is applied, and an iron plating layer is electrodeposited on the outer periphery of the metal core material , hot or cold.
A method for producing an iron-coated composite material, which comprises subjecting to plastic working to a predetermined size .