JP2723800B2 - Gas shielded arc welding wire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas shielded arc welding wire used for gas shielded arc welding.
In particular, the present invention relates to a gas shielded arc welding wire capable of stably maintaining a welding arc.

[0002]

2. Description of the Related Art The demand for improving the performance of a gas shielded arc welding method used in the manufacture of automobiles, steel bridges, and the like is increasing year after year. Conventionally, in order to improve the gas shielded arc welding technique, an appropriate shield gas component and an improved control method of a welding power source have been performed.

However, in order to obtain a weld efficiently,
It is extremely important to prevent defects due to instability of the welding arc and to maintain a stable welding arc for a long time. The instability of the welding arc refers to fluctuations in the welding arc length that can be confirmed with the naked eye, disappearance of the welding arc for a short time that is not recognized by the naked eye (so-called broken welding arc), and short-circuiting between the wire and the molten pool (for a short time). (Hereinafter referred to as short circuit).

[0004] When the welding arc becomes unstable, the shape of the molten pool becomes irregular, and defects in the bead shape are likely to occur. Further, when the welding arc becomes unstable, it becomes necessary for the welding operator to finely adjust the welding arc length, and the welding efficiency is reduced.

To solve such problems, for example, after removing the residual lubricant on the surface of the wire, potassium carboxylate is fixed on the surface of the wire. An arc stabilizing technique for stabilizing the arc discharge phenomenon by regulating the amount of free copper powder has been proposed (Japanese Patent Publication No. 3-7703).
5).

[0006] Another method is to prevent the wear of the current-carrying copper chip and to prevent the wire feed conduit liner from being blocked by regulating the amount of copper powder remaining on the surface of the copper-plated wire. Has been proposed (Japanese Unexamined Patent Publication No.
1-3696).

[0007]

However, in the above-mentioned prior art, it is not possible to sufficiently reduce the occurrence of short-time arc breaking and short-circuiting which cannot be recognized by the naked eye. For this reason, in each of the prior arts described above, it is not possible to avoid deterioration in welding workability such as welding defects and a decrease in welding efficiency.

[0008] The present invention has been made in view of the above problems, it is possible to feed stably, it is possible to reduce short-term short-circuit with the molten pool and welding arc breakage, thereby An object of the present invention is to provide a gas shielded arc welding wire capable of reducing welding defects and improving welding efficiency.

[0009]

The gas shielded arc welding wire according to the present invention is characterized in that the amount of water contained in the surface deposit is 2% or less.

Preferably, the moisture content of the surface deposit is 0.5% or less, and more preferably, the moisture content of the surface deposit is 0.2% or less.

[0011] Further, the present invention provides a method for manufacturing a semiconductor device, comprising:
Wt% C, 0.30-1.10 wt% Si, 0.1 wt%.
85 to 2.60 wt% Mn, 0.001 to 0.0
30% by weight of P, 0.001 to 0.030% by weight of S
And 0.01 to 0.50% by weight of Cu, with the balance being iron and unavoidable impurities.

Further, the composition of the solid wire is as follows:
The composition contains 0.01 to 1.80% by weight of Ni,
0.01 to 0.70% by weight of Cr, 0.01 to 0.65
% Mo, 0.01 to 0.50% Al and at least one selected from the group consisting of Ti and / or Zr having a total weight of 0.01 to 0.30% by weight. can do.

[0013]

The present inventors have conducted various experimental studies to determine the conditions for maintaining a stable welding arc, and have found the following.

That is, based on the analysis result of the wire and the wire surface and the observation result of the welding arc phenomenon photographed by a high-speed camera, the moisture in the substance adhering to the wire surface shows that the wire between the current-carrying tip and the wire is displaced. And found that this made the arc unstable.

The moisture in the wire surface deposits is the remaining wire drawing lubricant and those that have been altered. That is, in consideration of the slipperiness (feedability) between the current-carrying tip and the wire, the moisture adhering to the wire surface is less than the lubricating film of the rust preventive or the lubricant applied for feed. Also, it has been found that metal contact easily occurs between the current-carrying chip and the wire, which results in poor feeding.

For this reason, the present invention regulates the amount of moisture in the wire surface deposits. As a result of numerous experiments by the present inventors, the amount of water contained in the surface deposits of the gas shielded arc welding wire is reduced. In the case of 2% or less, the wire for gas shielded arc welding can be fed stably, and it is possible to reduce the shortage of welding arc and short-time short-circuit between the wire for gas shielded arc welding and the molten pool. There was found.

The effect of preventing arc breakage and short-circuit due to the stable feeding of the wire is further improved by further reducing the moisture content of the surface deposit to 0.5% or less, and further improving the moisture content of the surface deposit. Is set to 0.2% or less, this effect is further improved.

The reasons for the increase in the amount of moisture in the surface deposits of the gas-shielded arc welding wire include the generation of moisture due to the decomposition of oil in the surface deposits and the use of lubricant in the wire drawing process before oil coating. It is considered to be residual. For this reason, as a means for regulating the amount of water, there is, for example, a method of regulating a decomposition reaction. This method suppresses the catalytic effect of the decomposition reaction by removing metal powder by a filter, and cools a wire and oil. The effect of heat is thereby suppressed. In addition, the amount of water can be regulated even if the remaining wire drawing lubricant is removed, and this method sufficiently dries the wire before the oiling treatment. With such a method, it is possible to regulate the amount of water in the surface deposits.

On the other hand, when the gas shielded arc welding wire is a solid wire, the chemical composition of the solid wire can be within the range specified in JIS Z3312. That is, the composition of the solid wire is preferably as defined in claim 4 or 5.

The reasons for adding the components of the solid wire and the reasons for limiting the composition in the present invention will be described below.

C: 0.001 to 0.15% by weight C is an indispensable element for obtaining deoxidation and strength of the weld metal. However, when the C content is less than 0.001% by weight, both deoxidation and strength are insufficient, and 0.15% by weight.
If the content is more than 10% by weight, hot cracking tends to occur in the weld metal. Therefore, the content of C is desirably 0.001 to 1.15% by weight.

Si: 0.30 to 1.10% by weight Si is added for deoxidizing the weld metal. However, S
When the i content is less than 0.30% by weight, deoxidation is insufficient,
If it exceeds 1.10% by weight, the toughness of the weld metal tends to decrease. Therefore, the content of Si is 0.30 to 1.10.
% By weight.

Mn: 0.85 to 2.60% by weight Mn is added to obtain deoxidation and strength of the weld metal. However, if the Mn content is less than 0.85% by weight, deoxidation and strength are insufficient, and if it exceeds 2.60% by weight, low-temperature cracking is liable to occur in the weld metal. Therefore, M
The content of n is desirably 0.85 to 2.60% by weight.

P: 0.001 to 0.030% by weight P is added to separate the droplet from the tip of the solid wire. However, when the P content is less than 0.001% by weight, the effect is insufficient, and when the P content exceeds 0.030% by weight, hot cracks are easily generated in the weld metal. Therefore, the content of P is desirably 0.001 to 0.030% by weight.

S: 0.001 to 0.030% by weight S is an effective component for detaching the droplet from the tip of the solid wire. However, if the S content is less than 0.001% by weight, the effect is insufficient, and if the S content exceeds 0.030% by weight, hot cracks are easily generated in the weld metal. Therefore, the content of S is desirably 0.001 to 0.030% by weight.

Cu: 0.01 to 0.50% by weight Cu is an indispensable element for increasing the electrical conductivity of the solid wire and increasing the strength of the weld metal. However, Cu
When the content is less than 0.01% by weight, the electrical conductivity and strength are insufficient, and when the content exceeds 0.50% by weight, high temperature cracks are easily generated in the weld metal. Therefore, the content of Cu is 0.1.
The content is desirably from 0.01 to 0.50% by weight.

It should be noted that Cu may exist in any state of being plated on the wire surface, being dissolved in steel, or being in the form of grain boundary precipitates. However, in order to improve the electrical conductivity of the wire, it is preferable that Cu is 0.10 to 0.40% by weight in a state where the surface of the wire is plated.

On the other hand, inevitable impurities include Be,
B, N, Mg, Ca, V, Co, Zn, As, Se, S
r, Y, Nb, Cd, In, Sn, Sb, Te, Ba,
There are W, Hg, Tl, Pb, Bi and the like. These impurities are each 0.05% by weight or less, and a total of 0.50% by weight.
If it is the following, it may be contained. It is preferable that the content of impurities is small. If the content of at least one of the above-mentioned impurity elements exceeds 0.05% by weight, adverse effects such as an increase in instability of the welding arc and an increase in crack susceptibility occur, and these elements are also adversely affected. When the total content exceeds 0.50% by weight, adverse effects such as an increase in welding arc instability and an increase in cracking susceptibility occur.

Further, in addition to the above components, one or more of the following components may be added to the solid wire in an appropriate amount.

Ni: 0.01 to 1.80% by weight Ni is an element effective for obtaining the low-temperature toughness and strength of the weld metal. However, when the Ni content is less than 0.01% by weight, both the low-temperature toughness and the strength are insufficient.
If it exceeds 80% by weight, hot cracks are likely to occur in the weld metal. Therefore, the content of Ni is 0.01 to 1.80.
% By weight.

Cr: 0.01 to 0.70 wt% Cr is an element effective for increasing the strength of the weld metal. However, if the Cr content is less than 0.01% by weight, the effect of increasing the strength is insufficient, and if it exceeds 0.70% by weight, the elongation of the weld metal tends to be insufficient, and low-temperature cracking tends to occur. . Therefore, the content of Cr is desirably 0.01 to 0.70% by weight.

Mo: 0.01 to 0.65% by weight Mo is an element effective for obtaining the low-temperature toughness and strength of the weld metal. However, when the Mo content is less than 0.01% by weight, both the low-temperature toughness and the strength are insufficient, and the Mo content is too low.
If it exceeds 65% by weight, hot cracking is apt to occur in the weld metal, and the elongation of the weld metal tends to be insufficient. Therefore, the content of Mo is desirably 0.01 to 0.65% by weight.

Al: 0.01 to 0.50% by weight Al is an element effective for deoxidizing a weld metal and adjusting a weld bead. However, the Al content is 0.01% by weight.
When the amount is less than the above, both deoxidation and bead shaping properties are insufficient. On the other hand, when the amount is more than 0.50% by weight, hot cracks are easily generated in the weld metal. Therefore, the content of Al is 0.01
It is desirably set to 0.50% by weight.

Ti and / or Zr; 0.01 to 0.30
% By weight Ti and Zr are effective components for reducing the deoxidation and spatter of the weld metal, and the same effect is obtained by adding any of them. Therefore, one or both of Ti and Zr may be added, but if the total content of Ti and / or Zr is less than 0.01% by weight, deoxidation and reduction of spatter are insufficient, and 0.30% or less. If the content is more than 10% by weight, hot cracking tends to occur in the weld metal. Therefore, the total content of Ti and / or Zr is desirably 0.01 to 0.30% by weight.

Since Ti is more effective in reducing sputtering than Zr, it is preferable to make Ti more than Zr.

[0036]

Next, an embodiment of the present invention will be described. First, a method for measuring the amount of water in the present invention will be described. There are many methods for analyzing the substance adhering to the surface of a gas-shielded arc welding wire (hereinafter, referred to as a wire). The most effective method was to collect and analyze attached substances on the surface by ultrasonic cleaning in an organic solvent such as ether.

According to this method, first, the wire is ultrasonically cleaned in an organic solvent such as petroleum ether, and the wire body is taken out of the organic solvent, and the organic solvent is filtered through a filter paper (membrane filter) having a pore diameter of 0.2 μm. To obtain a filtrate. The filtrate is mixed with an organic solvent and a wire surface deposit that has passed through a filter paper having a pore size of 0.2 μm. The filtrate thus obtained is allowed to stand at 50 ° C. or lower and at atmospheric pressure, and the organic solvent is gradually evaporated. The filtrate is subjected to gas chromatography analysis (GC analysis) every 3 hours.
To analyze the content of the organic solvent. As a result, the filtrate when the organic solvent is no longer detected is used as a measuring solution, and the water content in the measuring solution is determined according to JIS-K2275 (Test method for crude oil and petroleum product components). It is measured by the F method.

In this case, the obtained measurement solution does not contain an organic solvent, and consists only of the wire surface adhering matter passed through a filter paper having a pore size of 0.2 μm. % Of the weight) is the amount of water contained in the wire surface deposit.

Accordingly, the amount of water is not affected by the weight of the wire and the amount of the organic solvent, and is the most effective method for measuring the amount of water contained in the deposit on the wire surface. Also,
According to this method, a wire of several kg or more can be easily analyzed, so that a trace substance adhering to the surface of the wire can be collected with high accuracy. The water content specified in the present invention is measured by this method.

In this case, the ultrasonic cleaning is performed so that the wire surface is not damaged and copper powder and iron powder are not generated.

Next, an embodiment of the present invention will be specifically described. Rolling or drawing process, heat treatment process (if necessary), washing process, copper plating process, washing process, finish drawing process, washing process, feeding or rust prevention for solid wire having the composition shown in Table 1 below , And each of the steps of an oil application step and a spool winding or large-capacity pack manufacturing step were sequentially performed.

In this case, by appropriately changing the conditions of each step, the amount of water contained in the surface deposits was changed variously, welding was performed on a mild steel base material, and welding workability was evaluated.
The welding conditions are as follows.

Welding conditions Solid wire diameter: 1.2 mm Current: 280 (A), DCEP (DC reverse polarity) Voltage: 32 (V) Shielding gas: CO ₂ gas, 25 l / min.

Table 1 also shows the results of the sensory evaluation of the moisture content of the surface deposits on the solid wire and the welding workability when welding was performed under these welding conditions. In addition, as Comparative Examples 13 to 18, welding workability was also evaluated with respect to the results of similar welding using solid wires having compositions deviating from claims 4 and 5 of the present application.

[0045]

[Table 1]

In the workability evaluation column, the welding workability was expressed by a sensory evaluation in five stages. 5 represents excellent, 3 represents good, 1 represents poor, 4 represents an intermediate between excellent and good, and 2 represents an intermediate between good and poor.

As is clear from Table 1, the workability is excellent in Examples 1 to 12 in which the amount of water on the surface of the solid wire is 2% or less. That is, the solid wire of the present embodiment is fed stably, and short-time short-circuiting between the solid wire and the molten pool and welding arc breakage can be reduced. As a result, it is possible to reduce welding defects and improve welding efficiency. On the other hand, in Comparative Examples 13 to 18, since the water content of the surface deposit exceeded 2%,
The welding workability was low.

[0048]

According to the present invention, since the moisture content of the surface deposits on the gas-shielded arc welding wire is regulated to 2% or less, the gas-shielded arc welding wire is fed stably, Short-time short-circuits between the arc welding wire and the molten pool and the breakage of the welding arc can be reduced. As a result, it is possible to reduce welding defects and improve welding efficiency.

Claims (5)

(57) [Claims] 1. A gas shielded arc welding wire characterized in that the amount of water contained in the surface deposit is 2% or less. 2. The gas shielded arc welding wire according to claim 1, wherein the moisture content of the surface deposit is 0.5% or less. 3. The gas shielded arc welding wire according to claim 2, wherein the water content of the surface deposit is 0.2% or less. 4. 0.001 to 0.15% by weight of C,
0.30 to 1.10% by weight of Si, 0.85 to 2.
60 wt% Mn, 0.001 to 0.030 wt% P, 0.001 to 0.030 wt% S and 0.01
The gas shielded arc welding according to any one of claims 1 to 3, wherein the solid wire contains Cu in an amount of 0.5 to 0.50% by weight and the balance is iron and inevitable impurities. For wire. 5. 0.001 to 0.15% by weight of C,
0.30 to 1.10% by weight of Si, 0.85 to 2.
60 wt% Mn, 0.001 to 0.030 wt% P, 0.001 to 0.030 wt% S and 0.01
To 0.50% by weight of Cu,
To 1.80% by weight of Ni, 0.01 to 0.70% by weight of Cr, 0.01 to 0.65% by weight of Mo, 0.0
1 to 0.50% by weight of Al and at least one selected from the group consisting of Ti and / or Zr having a total weight of 0.01 to 0.30% by weight, with the balance being iron and unavoidable impurities. The gas-shielded arc welding wire according to any one of claims 1 to 3, wherein the wire is a solid wire having the following composition.