KR101989308B1 - A solid wire having reduced slag - Google Patents

Abstract

An embodiment of the present invention is a method of manufacturing a semiconductor device, comprising: 0.02 to 0.08 weight% of carbon (C), 0.2 to 1.0 weight% of silicon (Si), 0.9 to 1.5 weight% of manganese (Mn) ) Of 0.02 to 0.025% by weight, the balance iron (Fe) and impurities, and X represented by the following formula is 60.6 to 200:
<Expression>
X = [Al] / [Ti] * 100
Where [Ti] and [Al] are the contents (wt%) of the titanium and the aluminum relative to the total weight of the solid wire, respectively.

Description

A SOLID WIRE HAVING REDUCED SLAG &lt; RTI ID = 0.0 &gt;

The present invention relates to a solid wire in which slag is reduced, and more particularly, to a solid wire in which slag is reduced and the produced slag can be easily peeled off.

As the steel sheet of the structural member of the lower body of the automobile, a galvanized steel sheet, a zinc alloy coated steel sheet, a non-coated steel sheet, or the like is used. In addition, gas shielded arc welding is often applied to the welding of the structural member of the undercarriage.

However, when the steel sheet is arc welded, a blowhole may be generated in the welded joint portion, that is, the weld metal. Particularly, it is known that a blowhole tends to occur when a galvanized steel sheet or a zinc alloy plated steel sheet is arc-welded.

In the blowhole, bubbles are generated by gasification of CO ₂ gas or various adsorption components and further by gasification by reaction of low-temperature gasification reaction components, because carbon in the weld metal reacts with oxygen due to heat input at the time of welding, As a result of being trapped in the weld metal with the solidification of the metal, it remains as a public. Particularly, in zinc or zinc alloy coated steel sheets, a zinc or zinc alloy plated on the surface of the steel plate is evaporated at the time of welding, and the zinc vapor becomes bubbles in the molten weld metal. If a large number of such blowholes are generated, the strength of the welded joint is lowered to cause a problem as a structural member, paint defects tend to occur, and the appearance and shape of the weld bead are liable to be defective.

On the other hand, a steel sheet used for a structural member of a car lower body is usually painted by electrodeposition coating after welding. However, in the case of welding by the gas-shielded arc welding method, since CO ₂ , Ar + 5 to 20% CO ₂ is used for the shield gas, deoxidation elements such as Si and Mn in the welding wire, It reacts with the component and becomes an oxide. The oxide floats on the molten weld metal surface and becomes slag. Since such slag (oxide) does not have conductivity, electrodeposition coating is not carried out on the slag on the surface of the weld bead, and coating defects and coating defects are generated, and corrosion resistance and aesthetics of the welded portion after coating are lowered.

Therefore, in the gas shielded arc welding of a steel sheet used for a structural member of a car lower body, especially a zinc or zinc alloy coated steel sheet, blowholes are prevented from occurring in the weld metal of the weld joint as much as possible. At the same time, it is very important to suppress the occurrence of slag on the weld metal surface.

Japanese Unexamined Patent Application Publication No. 07-080478 discloses a welding wire used for gas shield arc welding of a zinc or zinc alloy plated steel sheet, which mainly suppresses the occurrence of blowholes and accompanying pits in gas shield arc welding A welding wire is disclosed. The disclosed welding wire comprises, by weight percent, C; 0.03 to 0.15%, Si; 1.00 to 2.50%, Mn; 0.10 to 1.00%, with the proviso that Mn / Si is in the range of 0.65% or less; P; 0.0015 to 0.200% in total of one or two of Al and Ti, 0.0050 to 0.0500% in total of one or both of S and O, the balance being Fe and unavoidable impurities will be.

Japanese Patent Laid-Open No. 62-124095 discloses an invention for improving slag releasability. That is, the slag produced after welding mainly contains a metal oxide of SiO ₂ -FeO-MnO system, the property of which is determined by the composition ratio of Si and Mn in the weld metal, the amount of Si and the amount of Mn in the weld metal are high Si And low Mn.

It is an object of the present invention to provide a solid wire in which the amount of slag generated during welding or welding is remarkably reduced and inevitably the peelability of the produced slag is improved, .

One aspect of the present invention relates to a method of manufacturing a semiconductor device, which comprises 0.02 to 0.08 weight% of carbon (C), 0.2 to 1.0 weight% of silicon (Si), 0.9 to 1.5 weight% of manganese (Mn), 0.01 to 0.035 weight% of titanium (Ti) 0.02 to 0.025% by weight, the balance of iron (Fe) and impurities, and X represented by the following formula is 60.6 to 200.

<Expression>

X = [Al] / [Ti] * 100

Where [Ti] and [Al] are the contents (wt%) of the titanium and the aluminum relative to the total weight of the solid wire, respectively.

In one embodiment, X may be 60.6-95.

In one embodiment, X may range from 120 to 200.

In one embodiment, the solid wire may further comprise 0.02 wt% or less of phosphorus (P).

In one embodiment, the solid wire may further comprise 0.025 to 0.035 weight percent sulfur (S).

In one embodiment, the solid wire may further include 0.3% by weight or less of copper (Cu).

In one embodiment, the solid wire may further include 0.025 to 0.05 wt% of chromium (Cr).

In one embodiment, the solid wire may further comprise less than 0.002 wt% vanadium (V).

In one embodiment, the solid wire may further include not more than 0.01% by weight of molybdenum (Mo).

In one embodiment, the impurities may comprise at least one of 0.005-0.02 wt% nickel (Ni) and 0.001-0.01 wt% zirconium.

According to an aspect of the present invention, by controlling the composition of the solid wire to a certain range, the amount of slag generated during welding or welding can be remarkably reduced.

In addition, the solid wire adjusts the surface tension and heat shrinkage characteristics of the weld slag so that the slag inevitably produced can be easily peeled off.

It should be understood that the effects of the present invention are not limited to the effects described above, but include all effects that can be deduced from the description of the invention or the composition of the invention set forth in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a graph showing the composition of a solid wire according to a production example of the present invention and a comparative production example. Fig.
2 is a graph showing the surface tension according to the composition of molten slag.
Figure 3 shows the volume change associated with the solidification of molten slag.
4 shows the composition of the molten slag produced from the solid wire according to the embodiment of the present invention and the comparative example.
5 is a photograph of a weld bead formed from a solid wire according to the production example of the present invention and the comparative production example.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements, not excluding other elements unless specifically stated otherwise.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

One aspect of the present invention relates to a method of manufacturing a semiconductor device, which comprises 0.02 to 0.08 weight% of carbon (C), 0.2 to 1.0 weight% of silicon (Si), 0.9 to 1.5 weight% of manganese (Mn), 0.01 to 0.035 weight% of titanium (Ti) 0.02 to 0.025% by weight, the balance of iron (Fe) and impurities, and X represented by the following formula is 60.6 to 200.

<Expression>

X = [Al] / [Ti] * 100

Where [Ti] and [Al] are the contents (wt%) of the titanium and the aluminum relative to the total weight of the solid wire, respectively.

Carbon (C): 0.02 to 0.08 wt%

Carbon has a deoxidizing action and improves the strength of the weld metal. In the case of thin plate welding, it is not necessary to consider multi-layer welding, so it is not necessary to consider the strength reduction due to reheating, and it is not necessary to consider reduction in strength by reheating. From low strength mild steel of 300MPa or less to high tensile steel plate of 590MPa or more, Can be obtained.

However, if the content of carbon is lowered to less than 0.02 wt%, the strength is applicable only to mild steel and general versatility is lowered. When the content of carbon is more than 0.08% by weight, crack resistance is remarkably lowered. In addition, the amount of spatters and fumes generated increases, deoxidization is excessively performed, oxygen in the melting paper is decreased, and the viscosity and surface tension of the melting paper are increased. As a result, the barrier action for alleviating the arc force is lowered, and the content of the material can be deteriorated.

Silicon (Si): 0.2 to 1.0 wt%

Silicon can increase the electrical resistance while securing the strength of the solid wire. When the amount is less than 0.2% by weight, the strength is lowered, and it is difficult to apply it to other than mild steel. Further, since the electric resistance of the solid wire is excessively lowered, the current value per feed amount is increased. As a result, the heat input is increased, so that the content-locking property and the under-cut property may be deteriorated. Therefore, it is necessary to contain 0.2 wt% or more of silicon.

On the other hand, when the content of silicon is more than 1.0% by weight, deoxidation is excessively carried out, oxygen in the molten metal decreases, and the viscosity and surface tension of the fused paper become high. As a result, the barrier action for alleviating the arc force is lowered, and the content of the undercoat layer may be deteriorated.

Manganese (Mn): 0.9 to 1.5 wt%

The manganese can secure the strength of the solid wire and increase the electrical resistance. When the content is less than 0.9% by weight, the strength is lowered, and it is difficult to apply it to other than mild steel. Further, since the electric resistance of the solid wire is excessively lowered, the current value per feed amount is increased. As a result, the heat input is increased, so that the content-locking property and the under-cut property may be deteriorated. Therefore, it is necessary to contain at least 0.2 wt% of manganese.

On the other hand, when the content of manganese is more than 1.0% by weight, deoxidation is excessively carried out, oxygen of the molten oil decreases, and the viscosity and surface tension of the melting paper become high. As a result, the barrier action for alleviating the arc force is lowered, and the content of the undercoat layer may be deteriorated. In addition, an excessive amount of slag may be generated and paintability may be deteriorated.

Titanium (Ti): 0.01 to 0.035% by weight

Titanium can improve arc stability in the high current region. Since titanium is a deoxidizing element, generation of blowholes can be suppressed. If the content of titanium is less than 0.01% by weight, it is difficult to sufficiently realize such effect. If the content is more than 0.035% by weight, excess slag may occur. Therefore, the content of titanium can be adjusted to 0.01 to 0.035% by weight, preferably 0.025 to 0.035% by weight, in consideration of the balance of the inhibition of blowholes and slag generation.

Aluminum (Al): 0.02 to 0.025 wt%

Aluminum is a strong deoxidizing element, which accelerates the deoxidation of molten metal during arc welding, but it can increase the amount of slag generated. If the content of aluminum in the solid wire is less than 0.02 wt%, it is difficult to sufficiently realize such an effect. If the aluminum content is more than 0.025 wt%, slag generation reaction may be promoted.

Further, in the solid wire, X represented by the following formula may be 60.6-200.

<Expression>

X = [Al] / [Ti] * 100

Where [Ti] and [Al] are the contents (wt%) of the titanium and the aluminum relative to the total weight of the solid wire, respectively.

In particular, referring to FIG. 1, when the solid wire satisfies the condition that the X is 60.6 to 200 and the Al content is 0.02 wt% or more, the slag generation amount is reduced and the slag produced is remarkably improved .

2 is a graph showing the surface tension according to the composition of molten slag. Referring to FIG. 2, as the content of SiO ₂ and TiO ₂ in molten slag increases, the surface tension decreases. On the other hand, the surface tension increases as the content of Al ₂ O ₃ and MnO increases. That is, the solid wire includes a certain amount of Si and Mn in consideration of the basic physical properties to be provided by the solid wire such as strength, crack resistance and electrical resistance, and by increasing the content of Ti and Al compared to the conventional one, It is possible to increase the surface tension of the molten slag produced from the molten slag, whereby the solidified slag can be easily peeled off. At this time, the surface tension of the molten slag may be 580 mN / m or higher, preferably 600 mN / m or higher, and more preferably 600 to 650 mN / m. If the surface tension of the molten slag is more than 650 mN / m, the barrier action for alleviating the arc force may be lowered, and the content of the slag may be deteriorated. The X for controlling the surface tension of the molten slag to the above range may be 120 to 200, preferably 180 to 200. [

Figure 3 shows the volume change associated with the solidification of molten slag. 3, Al ₂ O ₃ , Al ₂ SiO ₅ and Mn ₃ Al ₂ Si ₃ O ₁₂ contained in molten slag generated from a solid wire containing a certain amount of Al are iron (Fe , steel, there is a large difference in the volume change accompanying solidification, so that the solidified slag can be easily peeled off. At this time, the amount of change in volume accompanying the solidification of the molten slag may be 2.00 * E-04 cm ³ or more, preferably 2.00 * E-04 to 5.00 * E-04 cm ³ . The X for adjusting the volume change to the above range may be 60.6 to 95. [

On the other hand, the solid wire may further include the following components.

Phosphorus (P): not more than 0.02% by weight

The solid wire may further comprise 0.02 wt% or less of phosphorus (P). Phosphorus is an inevitable impurity present in steel, and is generally contained as an impurity in a solid wire for arc welding. At this time, phosphorus is one of the main elements causing high-temperature cracking of the weld metal, and it is desirable to suppress as much as possible. If the content of phosphorus is more than 0.02% by weight, high temperature cracking of the weld metal becomes remarkable. Therefore, the content of phosphorus in the solid wire may be 0.02 wt% or less, and preferably 0.001 to 0.02 wt% in consideration of cost and productivity.

Sulfur (S): 0.025 to 0.035 wt%

The solid wire may further include 0.025 to 0.035% by weight of sulfur (S). Sulfur is an inevitable impurity existing in the steel, and it is generally contained in the solid wire for arc welding as an impurity. At this time, the sulfur reduces the surface tension of the weld bead and makes the slag wet to the weld bead in a shape close to a sphere, so that the peelability of the slag can be improved. However, if the content of sulfur is more than 0.035 wt%, crack resistance of the weld metal may be deteriorated. Therefore, the content of sulfur in the solid wire may be 0.035% by weight or less, and preferably 0.025 to 0.035% by weight in consideration of cost and productivity.

Copper (Cu): not more than 0.3 wt%

The solid wire may further contain 0.3% by weight or less of copper (Cu). Copper is an element derived from copper plating on the wire surface as needed. Copper plating is a surface treatment method capable of stabilizing the feedability and conductivity of the wire. When copper plating is performed, a certain amount of copper may be included in the solid wire. If the content of copper is more than 0.3% by weight, the susceptibility to cracking may be increased. Therefore, the content of copper in the solid wire may be 0.3% by weight or less, preferably 0.05 to 0.3% by weight in consideration of the feedability and conductivity of the wire.

Cr (Cr): 0.025 to 0.05 wt%

The solid wire may further include 0.025 to 0.05 wt% of chromium (Cr). In general, chromium improves the strength of the weld metal. If the content of chromium is less than 0.025% by weight, it is difficult to sufficiently improve the strength of the weld metal, and if it exceeds 0.05% by weight, the toughness of the weld metal may be deteriorated.

Vanadium (V): not more than 0.002 wt%

The solid wire may further include 0.002 wt% or less of vanadium (V). Vanadium can also improve the strength of the weld metal and, if included in the solid wire together with the chromium, can further improve the strength of the wire. If the content of vanadium exceeds 0.002% by weight, the toughness of the weld metal may be deteriorated. Therefore, the content of vanadium in the solid wire may be 0.002 wt% or less, preferably 0.0001-0.02 wt%, considering the strength of the weld metal.

Molybdenum (Mo): not more than 0.01% by weight

The solid wire may further include molybdenum (Mo) of 0.01 wt% or less. Molybdenum can improve the strength of the weld metal. The lower limit for achieving this effect may be 0.001% by weight, but is not limited thereto. On the other hand, if the content of molybdenum is more than 0.01% by weight, the content of the molybdenum may be deteriorated, and the amount of spatter may be increased.

impurities

The impurities may include at least one of 0.005 to 0.02% by weight of nickel (Ni) and 0.001 to 0.01% by weight of zirconium. If the content of nickel and zirconium is out of the above range, the content of the alloy may be deteriorated, and a large amount of spatter may occur.

Hereinafter, embodiments of the present invention will be described in detail.

Example

In order to evaluate the peelability of the slag inevitably generated after welding with solid wire, the surface tension of the molten slag derived from the solid wire having the composition shown in the following Table 1 and the volume change accompanying the solidification of the slag were measured, Are shown together in Table 1 below.

ingredient Example 1 Example 2 Example 3 Example 4 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Si 0.2 0.2 0.5 0.5 0.2 0.2 0.5 0.5 Mn One One One One One One One One Ti 0.01 0.03 0.01 0.03 0.01 0.03 0.01 0.03 Al 0.02 0.02 0.02 0.02 0.01 0.01 0.01 0.01 Fe Balance Balance Balance Balance Balance Balance Balance Balance Slag
Al ₂ O ₃
Included include include include include Without Without Without Without X
([Al] / [Ti]
* 100) 200 66.7 200 66.7 100 33.3 100 33.3 Surface tension
(mN / m) 645 584 623 591 589 575 557 561 ΔV
(cm ³ ) 2.38E-04 4.43E-04 2.18E-04 3.94E-04 - 5.46E-05 - 1.51E-04

(Unit: wt%)

Referring to Table 1, since the molten slag of Examples 1 to 4 contains solid Al ₂ O ₃ derived from Al contained in the solid wire, slag peeling property due to surface tension and volume change is excellent It is expected.

Specifically, in the case of Examples 1 and 3 in which X is in the range of 180 to 200, since the surface tension of molten slag is large, the produced slag can be easily peeled off. On the other hand, in the case of Examples 2 and 4 in which X is in the range of 50 to 70, since the solidification volume change of the molten slag is large, the slagability of the resulting slag can be remarkably improved accordingly.

Manufacturing example

The compositions of the solid wires according to Production Examples 1 to 4 and Comparative Production Examples 1 to 3 are shown in Table 2 below.

ingredient Production Example 1 Production Example 2 Production Example 3 Production Example 4 Comparative Preparation Example 1 Comparative Production Example 2 Comparative Production Example 3 C 0.045 0.055 0.072 0.073 0.07 0.072 0.081 Si 0.631 0.79 0.543 0.487 0.65 0.524 0.458 Mn 1.192 1.47 1.214 1.21 1.18 1.25 1.199 P 0.01 0.017 0.01 0.01 0.012 0.01 0.01 S 0.026 0.03 0.032 0.035 0.0089 0.004 0.06 Ni 0.014 - 0.014 0.014 0.01 0.014 0.014 Cr 0.031 - 0.031 0.031 0.02 0.031 0.031 Mo 0.003 - 0.003 0.003 0.01 0.003 0.003 Cu 0.213 0.01 0.213 0.213 0.201 0.213 0.213 V 0.001 - 0.001 0.001 - 0.001 0.001 Ti 0.01 0.03 0.027 0.033 0.001 0.013 - Zr 0.001 0.002 0.001 0.001 - - - Al 0.02 0.025 0.025 0.02 - 0.002 - Ca - 0.0001 - - - - Fe Balance Balance Balance Balance Balance Balance Balance X
([Al] / [Ti]
* 100) 200 83.3 92.6 60.6 0.0 15.38 -

(Unit: wt%)

Experimental example: Weld bead appearance evaluation

FIG. 5 is a photograph of weld beads produced after welding using solid wires according to Production Examples and Comparative Production Examples. FIG. 5, in Comparative Production Examples 1 to 3, a large amount of slag was observed in the center and side portions of the weld bead, whereas in the weld beads of Production Examples 1, 3 and 4, the amount of slag was reduced, , And in the weld bead of Production Example 1, slag hardly occurred.

It will be understood by those skilled in the art that the foregoing description of the present invention is for illustrative purposes only and that those of ordinary skill in the art can readily understand that various changes and modifications may be made without departing from the spirit or essential characteristics of the present invention. will be. It is therefore to be understood that the above-described embodiments are illustrative in all aspects and not restrictive. For example, each component described as a single entity may be distributed and implemented, and components described as being distributed may also be implemented in a combined form.

The scope of the present invention is defined by the appended claims, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

Claims (10)

A solid wire for gas shielded arc welding of zinc or zinc alloy plated steel sheet,
(Al), 0.02 to 0.025 wt% of aluminum (Al), 0.02 to 0.08 wt% of carbon (C), 0.2 to 1.0 wt% of silicon, 0.9 to 1.5 wt% of manganese (Mn) (Fe) and impurities,
X represented by the following formula is 180 to 200,
Wherein the molten slag produced from the solid wire has a surface tension of 580 to 650 mN / m.
<Expression>
X = [Al] / [Ti] * 100
Where [Ti] and [Al] are the contents (wt%) of the titanium and the aluminum relative to the total weight of the solid wire, respectively. delete delete The method according to claim 1,
Wherein the solid wire further comprises 0.02 wt% or less of phosphorus (P). The method according to claim 1,
Wherein the solid wire further comprises 0.025 to 0.035 weight percent sulfur (S). The method according to claim 1,
Wherein the solid wire further comprises 0.3% by weight or less of copper (Cu). The method according to claim 1,
Wherein the solid wire further comprises 0.025 to 0.05 weight percent chromium (Cr). The method according to claim 1,
Wherein the solid wire further comprises 0.002 wt% or less of vanadium (V). The method according to claim 1,
Wherein the solid wire further comprises molybdenum (Mo) of 0.01 wt% or less. The method according to claim 1,
Wherein the impurity comprises at least one of 0.005 to 0.02 weight percent nickel (Ni) and 0.001 to 0.01 weight percent zirconium.

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