WO2017142115A1

WO2017142115A1 - Clad steel wire and manufacturing method thereof

Info

Publication number: WO2017142115A1
Application number: PCT/KR2016/001849
Authority: WO
Inventors: 정진영; 김종성; 임재덕
Original assignee: 고려제강 주식회사
Priority date: 2016-02-16
Filing date: 2016-02-25
Publication date: 2017-08-24
Also published as: KR101787032B1; KR20170096413A

Abstract

The present invention relates to a clad steel wire and a manufacturing method thereof, the method comprising: a first step of plasma-heat treating the surface of a steel wire; a second step of cladding the steel wire, having undergone the first step, with a clad member in a strip state; a third step of plasma-heat treating the clad steel wire having undergone the second step; a fourth step of hot rolling the clad steel wire, having undergone the third step, using a rolling roll; and a fifth step of wire drawing the clad steel wire, having undergone the fourth step, using a wire drawing machine. As such, it is possible to improve the bonding property between a steel wire and a clad member, thereby manufacturing a steel wire excellent in corrosion resistance.

Description

Clad steel wire and manufacturing method

The present invention relates to a clad steel wire and a method of manufacturing the same, and more particularly, to a method of manufacturing a steel wire having excellent corrosion resistance by improving the bonding property between the steel wire and the clad member through a plasma heat treatment and a spiral cladding process.

Various bridges, such as suspension bridges and cable-stayed bridges, and wires used in the seabed should be excellent in durability. In particular, since wires are frequently in contact with seawater, wires are mainly made of steel wire. Steel wire is a wire made of steel, which is frequently used for bridges and buildings. However, even in the case of steel wire, if frequent exposure to sea water, the steel wire is corroded, so corrosion resistance is required. At this time, the corrosion resistance (corrosion resistance) refers to the property that corrosion is unlikely to occur.

As a general method for increasing the corrosion resistance of such steel wire, there are methods such as zinc plating, zinc-aluminum alloy plating, and grease oil coating. However, there is a limitation that the service life of the steel wire is not long. In order to overcome this problem, a method of fabricating clad steel wire through the clad process has been developed. A clad process means the process of overlapping and rolling a metal plate and a raw material mechanically. That is, by combining a variety of different metals together to take only the advantages of each metal. Even in the case of steel wire, after cladding process by combining with the clad molding member, it is possible to produce a clad steel wire excellent in corrosion resistance.

As an example of a method of manufacturing such a clad steel wire, Korean Unexamined Patent Publication No. 2009-0043816 (published on May 07, 2009) discloses an invention related to a clad wire manufacturing method. Reference will now be made to FIG. 1 to describe the disclosed invention.

Disclosed is a step of manufacturing the clad molding member 10 formed in the U-shape by passing the clad molding member 10 through the first forming roller 20, the feeding device inside the U-shaped clad molding member 10 Inserting the wire 12 into the 22, passing the clad molding member 10, the wire 12 is inserted through the second forming roller 30 to close the opened part of the clad molding member 10 Molding in the shape of a ruler, welding and sealing with the welding device 40, and transferring the welded clad forming member 10 to the drawing device 50 to draw in the form of a clad wire 100. A method of manufacturing the clad wire 100 is disclosed.

However, when manufacturing the clad wire 100 according to the disclosed invention, there is a disadvantage in that the integrity of the bonding surface of the clad molding member 10 and the wire 12 is low, the soundness is inferior. In cladding the clad molding member 10 and the wire 12, the cladding member 10 and the wire 12 are manufactured to have high bonding properties, thereby improving the life of the clad wire 100 and ultimately, There is a need for an invention that can increase corrosion resistance in seawater.

The present invention relates to a clad steel wire and a method for manufacturing the same, and an object thereof is to manufacture a steel wire having excellent corrosion resistance by improving the bonding property between the steel wire and the clad member through a plasma heat treatment and a spiral cladding treatment.

In order to achieve the above object, a method of manufacturing steel wire which requires corrosion resistance is performed by plasma heating of the surface of the steel wire, and the clad in strip state of the steel wire passed through the first step. Hot rolling of the second and third cladding wires subjected to the cladding treatment and the third and third cladding wires subjected to the plasma heating treatment using a rolling roll. And a fifth step of wire drawing the clad steel wire which has undergone the fourth step and the fourth step of processing by using a drawing machine.

In addition, the heating temperature of the first step of the clad steel wire manufacturing method may be characterized in that 100 ~ 200 ℃.

In addition, the cladding treatment of the second step of the clad steel wire manufacturing method includes the step of twisting the cladding member spirally along the longitudinal direction of the steel wire passed through the first step with the steel wire passed through the first step. You can do

In addition, the heating temperature of the third step of the clad steel wire manufacturing method may be characterized in that 500 ~ 800 ℃.

In addition, the hot rolling of the fourth step of the clad steel wire manufacturing method may be characterized by rolling so that the reduction ratio of the cross-sectional area of the clad steel wire passed through the third step is 5 to 10%.

In addition, the clad member of the clad steel wire manufacturing method may be characterized in that any one of aluminum, stainless steel, titanium and titanium alloy.

Bonding between the steel wire and the clad member is improved through the plasma heat treatment on the surface of the steel wire according to the present invention, thereby increasing the corrosion resistance of the clad steel wire and extending its life.

In addition, the hot rolling process improves the bond between the steel wire and the clad member, thereby increasing the corrosion resistance of the clad steel wire and extending its life.

1 is a view showing the prior art related to the clad wire manufacturing method.

2 is a view showing a clad steel wire manufacturing method according to the present invention.

3 is a diagram illustrating a cladding treatment step of a clad steel wire according to the present invention;

4 is a cross-sectional view of the clad steel wire according to the present invention.

5 is a view showing a flowchart of a method for manufacturing a clad steel wire according to the present invention.

Hereinafter, with reference to the accompanying drawings a preferred embodiment according to an embodiment of the present invention will be described in detail.

2 is a view showing a clad steel wire manufacturing method according to the present invention. Hereinafter, a method of manufacturing a clad steel wire will be described with reference to FIG. 2.

The prepared steel wire 100 is subjected to a first step S100 of plasma heating 210 the surface of the steel wire 100. First prepare the steel wire (100). At this time, the steel wire 100 is preferably a high strength steel wire 100 having a carbon content of 0.6 ~ 1.0%. When the carbon content of the steel wire 100 is low, the tensile strength of the clad steel wire is lowered, causing a problem that the service life is shortened. Thereafter, the surface of the prepared high strength steel wire 100 is subjected to plasma heating treatment 210. The plasma heating treatment 210 in the first step of the present invention refers to a process of heating the steel wire 100 to 100 to 200 ° C. by treating plasma on the surface of the steel wire 100.

Plasma refers to a gaseous state that is separated into electrons with positive charges and ions with positive charges at very high temperatures. It is often called the 'fourth material state' and has a high degree of charge separation, which is neutral due to the same negative and positive charge as a whole. Plasma is used in many fields and is also used in metal processing. The reason why the plasma heating treatment 210 is preferable in the present invention is that the heating time of the steel wire 100 is shortened by being heated to ultra high temperature compared to other heating methods. Due to the shortening of the heating time, the probability that separate impurities are combined with the steel wire 100 is reduced. In addition, since plasma heating is a clean heating source, there is an advantage that the heating environment can be effectively controlled. Due to the advantages of the plasma heat treatment 210 it is possible to produce a high corrosion resistance and high quality final clad steel wire (120).

Plasma is generated by the plasma module, and the plasma is treated on the surface of the steel wire 100. The reason for treating the plasma on the surface of the steel wire 100 is that in the process in which the steel wire 100 and the clad member 110 are later bonded, the surface of the steel wire 100 is washed to remove foreign substances and to clean the joint surface. This is to increase the adhesion between the steel wire 100 and the clad member 110.

When the surface of the steel wire 100 is plasma treated, the steel wire 100 is heated. When the steel wire 100 is heated in this way, the bond between the steel wire 100 and the clad member 110 is increased. At this time, the heating temperature at which the steel wire 100 is heated is preferably 100 ~ 200 ℃. When the heating temperature of the steel wire 100 is 100 ° C. or less, the temperature required for heat diffusion during the bonding process between the steel wire 100 and the clad member 110 is low, so that the joint surface is not good, and the temperature is higher than 200 ° C. The surface of the 100 becomes a high temperature and reacts rapidly with oxygen, and an oxidation scale phenomenon occurs in which thin film-like materials are formed on the surface of the steel wire 100. Due to this oxidation scale phenomenon, the bond between the steel wire 100 and the clad member 110 is reduced. Therefore, the heating temperature of the steel wire 100 through the plasma in the first step (S100) of the present invention is preferably 100 ~ 200 ℃.

The steel wire 101 that has passed through the first step S100 is subjected to the second step S110 that is cladding with the cladding member 110. Hereinafter, the second step S110 in the present invention will be described.

As described above, the cladding refers to a process of mechanically bonding a metal plate or a material by rolling over it. In the present invention, the steel wire 101 and the clad member 110 which passed through the first step are rolled up. At this time, the clad member 110 is preferably in a strip state. The strip state means a long thin strip of metal. When the clad member 110 in the strip state is wound around the cylindrical steel wire 101 through the first step extending in the longitudinal direction, the contact area between the steel wire 101 through the first step and the clad member 110 is increased. This is because the bonding property is excellent. In addition, the material of the clad member 110 is preferably any one of aluminum, stainless steel, titanium and titanium alloy. Aluminum is a metal element belonging to 3 cycles in group 13 of the periodic table, and is used in window sill pots and has a feature of poor corrosion. Stainless steel is a generic term for corrosion-resistant steel made for the purpose of improving the lack of corrosion resistance, which is the biggest defect of iron, and is excellent in corrosion resistance and heat resistance compared to conventional carbon steel. Titanium has a very high stiffness and elastic modulus, and is widely used in wire and other industrial materials, and mainly forms an alloy with iron to form a titanium alloy. Titanium and titanium alloys also have the advantage of excellent corrosion resistance. As such, if the material of the clad member 110 is any one of aluminum, stainless steel, titanium, and titanium alloy, the clad member 110 meets the purpose of manufacturing the final clad steel wire 120 requiring corrosion resistance.

In the cladding process 300, the clad member 110 is generally wrapped in a U shape around the steel wire 101 which has undergone the first step, and a portion of the cladding member 110 that is not connected to the end of the clad member 110 is welded. The steel wire 101 and the clad member 110 which passed through the first step by the U-shaped joining method are joined. However, in the present invention, as an embodiment of the bonding method, a spiral processing method is used. Hereinafter, the spiral cladding process of the final clad steel wire 120 according to the present invention will be described with reference to FIG. 3.

FIG. 3 is a view showing a state of the clad steel wire 102 in which the cladding process 300 is completed, that is, passed through the second step. The cladding member 110 is spirally twisted about the steel wire 101 passed through the first step formed in the longitudinal direction, and the longitudinal direction of the steel wire 101 passed through the first step is spaced at regular intervals between the clad members 110. As a result, it is closely attached. At this time, since the clad member 110 spirally winds the steel wire 101 passed through the first step in a spiral manner, the clad member 110 forms a constant angle with respect to the center line in the longitudinal direction of the steel wire 101 passed through the first step while forming a predetermined angle. The steel wire 101 is wound around.

As described above, the clad member 110 is compared with the form of spirally twisting the steel wire 101 which has undergone the first step and the method of winding the conventional clad member 110 in a U shape. FIG. 4 is a cross-sectional view of the clad steel wire 102 which has undergone the second step. Referring to FIG. 4 below. In the cladding process, in the conventional case, since the end portions of the clad member 110 are to be welded on the upper portion of the steel wire 101 which has undergone the first step, the clad member surrounding the steel wire 101 which has undergone the first step ( The gap between the ends of 110 is bound to occur. Due to the gap of the clad member 110, the bond between the steel wire 101 and the clad member 110, which has undergone the first step, becomes low, resulting in a shortened life. However, since the spiral cladding treatment method 300 according to the present invention is twisted in a spiral manner, as shown in FIG. 4, the clad member 110 surrounding the steel wire 101 which has undergone the first step has undergone the first step. Since 101 is continuously wrapped, there is no gap between the clad members 110, and there is no need to weld the clad members 110 separately. Due to this structure, the bond between the steel wire 101 and the clad member 110 which passed through the first step is increased. As a result, the life of the final clad steel wire 120 is made to be long, and meets the purpose of manufacturing the final clad steel wire 120 is required corrosion resistance according to the present invention.

The cladding steel wire 102 that has undergone the cladding process 300, that is, the second step, is subjected to the third step S120 of being subjected to the plasma heating treatment 220. Plasma heat treatment 220 in the third step is subjected to the same plasma treatment method as plasma heat treatment 210 in the first step. The clad steel wire 102 which has undergone the second step is in a state where the clad member 110 is bonded to the steel wire 101, and the plasma heating treatment 220 at this step has undergone the second step with the clad member 110. The bonding interface of the clad steel wire 102 is formed. Due to the bonding interface by the plasma heating treatment 220, the bonding property between the clad member 110 and the clad steel wire 102 which has undergone the second step is increased. At this time, unlike the plasma heating treatment 210 in the first step, the heating temperature of the clad steel wire 102 that passed through the second step of the plasma heating treatment 220 in the third step is preferably 500 to 800 ° C. When the heating temperature is 500 ° C. or less, the diffusion energy is insufficient, so that the bonding interface is not formed smoothly, and thus the bonding property between the clad steel wire 102 and the clad member 110 which has passed through the second step is low. In addition, when the heating temperature is 800 ° C or more, the mechanical and wire properties of the final clad steel wire 120 is degraded due to the decomposition of the structure of the clad steel wire 102 which has undergone the second step, thereby lowering the strength of the final clad steel wire 120. As a result, the life of the final clad steel wire 120 is shortened, and a problem that causes disconnection of the final clad steel wire 120 occurs in the drawing process 500 to be described later. Therefore, the heating temperature of the plasma heat treatment 220 in the third step is preferably 500 ~ 800 ℃.

The clad steel wire 103 which has passed through the third step S120 is subjected to the fourth step S130 which is a process 400 for hot rolling. Hot rolling, also called hot rolling, refers to rolling a metal material through a rolling roll 401 at a temperature above a recrystallization temperature. Generally, in metal materials, when the metal exceeds the melting point (absolute temperature) of the reference metal, diffusion occurs actively. Therefore, recrystallization starts in the cold worked material. Therefore, if the hot working (baking) at the temperature above the recrystallization start process hardening does not occur, there is an advantage that can be large deformation in one hot working. In addition, although not shown in the present invention, in general, in rolling, it is preferable to perform a post-treatment that is subjected to a large pressure reduction by hot rolling, followed by cold rolling. Therefore, if the clad steel wire 103 subjected to the third step in the present invention is subjected to the fourth step (S130) of the process of hot rolling 400 through the rolling roll 401, the third step in one rolling The adhesion between the clad steel wire 103 and the clad member 110 may be increased, and work hardening in the rolling process may be prevented.

When the clad steel wire 103 subjected to the third step becomes the clad steel wire 104 subjected to the fourth step through the hot rolling process 400, the reduction ratio of the cross-sectional area of the clad steel wire 103 subjected to the third step is 5 to 10. It is preferable to roll so that it may become%. If the cross-sectional area reduction rate is 5% or less, the bond between the clad steel wire 104 and the clad member 110 through the fourth step is weakened, and if the cross-sectional area reduction rate is 10% or more, the final clad steel wire completed due to the nonuniform thickness of the clad member 110. This is because a quality problem of 120 occurs. Therefore, rolling so that the reduction ratio of the cross-sectional area of the clad steel wire 103 which has passed through the third step is 5 to 10% corresponds to the purpose of extending the life and increasing the corrosion resistance of the final clad steel wire 120 of the present invention.

The clad steel wire 104 passed through the fourth step is subjected to the fifth step S140, which is a process of wire drawing 500. Wire drawing 500 is a type of metal processing method is a processing method to draw a line through the hole of the drawing machine 501 when manufacturing a steel wire, iron wire, etc. to make a line of the desired shape and dimensions. A bar of moderate thickness is drawn out through the drawing machine 501 punched in accordance with the shape of the cross section of the desired line to reduce the thickness, and the process is repeated to make the line thinner. According to the present invention, to make the final clad steel wire 120 of the desired shape and dimensions to make a hole of the drawing machine 501 corresponding to this, and using this, the final clad steel wire 120 through the drawing process (500) process ) Will finally produce. At this time, it is preferable that the drawing process 500 includes a process of coating the clad steel wire 104 which has undergone the fourth step through a separate machine (not shown). The coating treatment is to apply a lubricating coating on the material to facilitate the drawing process, and the lubricating coating suitable for the clad member 110 should be applied. In addition, the thickness of the clad member 110 of the final clad steel wire 120 is preferably 50μm or more. This is because when the thickness of the clad member 110 is too thin in the drawing process 500, sufficient corrosion resistance cannot be secured and thus does not meet the object of the present invention.

Figure 5 is a view showing a flow chart of the clad steel wire manufacturing method according to the present invention. Hereinafter, the clad steel wire manufacturing method according to the present invention will be described with reference to FIG. 5.

The steel wire 100 is subjected to a first step S100 of plasma heating the surface of the steel wire 100. At this time, the heating temperature of the plasma heat treatment 210 is preferably 100 ~ 200 ℃. The steel wire 101 having undergone the first step S100 passes through the cladding member 110 in the strip state and the second step S110 in which the cladding process 300 is performed. At this time, it is preferable that the cladding process 300 is performed while spirally twisting the clad member 110 to the center of the steel wire 101 which has passed through the first step S100. The clad steel wire 102 which has passed through the second step S110 is subjected to the third step S120 of the plasma heat treatment 220. At this time, the heating temperature of the plasma heating treatment 220 is preferably 500 ~ 800 ℃. The clad steel wire 103 which passed through the third step S120 is subjected to the fourth step S130 which is hot rolled through the rolling roll 401. At this time, the cross-sectional area reduction rate in the hot rolling (400) is preferably 5 to 10%. The clad steel wire 104 that passed through the fourth step (S130) is finally subjected to the fifth step (S140) that is drawn (500) through the drawing machine 501, and finally the final clad steel wire 120 is produced .

Although the present invention has been described with reference to various embodiments, the present invention is not limited thereto, and any thing that can be reasonably interpreted from the scope of the present invention will naturally belong to the scope of the present invention.

Claims

In the method of manufacturing a steel wire (corrosion resistance) is required,

A first step of plasma-heating the surface of the steel wire;

A second step of cladding the steel wire having passed through the first step with a clad member in a strip state;

A third step of plasma-heating the clad steel wire which has undergone the second step;

A fourth step of hot rolling the clad steel wire subjected to the third step by using a rolling roll; And

And a fifth step of wire drawing the clad steel wire which has passed through the fourth step by using a drawing machine.
The method according to claim 1,

Clad steel wire manufacturing method characterized in that the heating temperature of the first step is 100 ~ 200 ℃.
The method according to claim 2,

The cladding process of the second step,

And cladding the cladding member in a spiral manner along the longitudinal direction of the steel wire that passed through the first step, and closely attaching the clad member to the steel wire that passed through the first step.
The method according to claim 3,

Clad steel wire manufacturing method, characterized in that the heating temperature of the third step is 500 ~ 800 ℃.
The method according to claim 4,

The hot rolling process of the fourth step,

Clad steel wire manufacturing method characterized in that the rolling so that the reduction ratio of the cross-sectional area of the clad steel wire passed through the third step is 5 ~ 10%.
The method according to claim 1,

The clad member is a clad steel wire manufacturing method, characterized in that any one of aluminum, stainless steel, titanium and titanium alloy.
Clad steel wire, characterized in that the cladding member is spirally clad along the longitudinal direction of the steel wire.
The method according to claim 7,

The cladding member has a thickness of 50 μm or more,

The clad member is clad steel wire, characterized in that any one of aluminum, stainless steel, titanium and titanium alloy.