JPH0649685A - Production of iron-coated composite material - Google Patents

Abstract

PURPOSE:To produce an iron-coated composite material capable of being easily worked to a specified size by the plastic working such as rolling and drawing, without cracking the electrodeposited plating layer even when bent and excellent in mechanical characteristics. CONSTITUTION:A plastically workable metallic core is dipped in an aq. acidic iron salt soln., and an iron plating layer having >=9.97% purity and <=250 Vickers hardness and contg. 20-150ppm of carbon and <=40ppm of oxygen is electrodeposited on the core. Consequently, an extra-fine iron-coated composite material which has heterofore been hardly formed is obtained, the range of the use of the composite material is increased, and the electronic parts, etc., using the composite material are made compact, highly effective and inexpensive.

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 extremely difficult. 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, and electric current is applied to the outer circumference of the metal core material at a purity of 99.97% or more. , Vickers hardness 250 having a composition containing 20 ppm or more and 150 ppm or less of carbon content and 40 ppm or less of oxygen content
Provided is a method for producing an iron-coated composite material, which comprises electrodepositing the following iron plating layer.

In the above structure, it is preferable to use ferrous sulfate as the main component of the acidic iron salt aqueous solution. Further, it is preferable to use high-purity electrolytic iron as the anode during energization. Further, it is preferable that after the iron plating layer is electrodeposited, hot or cold plastic working is performed to work it into a predetermined size.

[0010]

The iron plating layer can be electrodeposited on the outer periphery of the metal core material by immersing the metal core material that can be plastically processed in the acidic iron salt aqueous solution and energizing the metal core material. At this time, if the purity of the iron plating layer is less than 99.97%, impurities existing in the electrodeposited iron plating layer are precipitated in the crystal grain boundaries of iron, deteriorating the mechanical properties, and causing rolling, drawing, etc. Since the iron-deposited iron plating layer is cracked during the plastic working of to produce a healthy iron-coated composite material, the component concentration of the electrolyte solution, temperature, current density and other factors should be adjusted so that the purity is 99.97% or more. Control electrolysis parameters.

From the results of experimentally confirming the relationship between the carbon content in the electrodeposited iron plating layer and the plastic workability of the iron-coated composite material, the carbon content of less than 20 ppm was 150 ppm.
If the content of carbon exceeds 20 ppm, the plastic workability is poor, and the electrodeposited iron plating layer is fragile and cracks, so that the processing cannot be performed easily. Control component concentration, temperature, current density and other electrolysis parameters.

Further, the electrodeposited iron plating layer having an oxygen content of more than 40 ppm is extremely inferior in plastic workability even if the carbon content is in the range of 20 to 150 ppm, so that the oxygen content should be 40 ppm or less. , Component concentration of electrolyte,
Control temperature, current density and other electrolysis parameters. Further, in the above composition, the electrodeposited iron plating layer having a Vickers hardness of more than 250 is fragile, easily cracks, and has poor plastic workability.
The component concentration, temperature, current density and other electrolysis parameters of the electrolytic solution are controlled as follows.

[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 electrodeposited iron plating apparatus 2 is composed of a hydrochloric acid bath, a sulfuric acid bath or a mixed bath thereof.
Purity is 99.97% in consideration of dimensions, plating thickness, etc.
As described above, the component concentration, temperature, current density, etc. of the electrolytic solution have a composition with a carbon content of 20 ppm or more and 150 ppm or less and an oxygen content of 40 ppm or less, and can form an electrodeposited iron plating layer with a Vickers hardness of 250 or less. Electrolysis parameters are determined. 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 circulating 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 (4)

[Claims] 1. A metal core material capable of plastic working is dipped in an acidic iron salt aqueous solution and is energized to have a purity of 99.97% or more and a carbon content of 20 ppm or more on the outer periphery of the metal core material.
A method for producing an iron-coated composite material, which comprises electrodepositing an iron plating layer having a Vickers hardness of 250 or less having a composition of 50 ppm or less and an oxygen content of 40 ppm or less. 2. The method for producing an iron-coated composite material according to claim 1, wherein ferrous sulfate is used as a main component of the acidic iron salt aqueous solution. 3. The method for producing an iron-coated composite material according to claim 1 or 2, wherein:
A method for producing an iron-coated composite material, which comprises using high-purity electrolytic iron. 4. The method for producing an iron-coated composite material according to claim 1, wherein the iron plating layer is electrodeposited, and then hot or cold plastic working is performed to work it into a predetermined size. A method for producing an iron-coated composite material, comprising: