JP2723799B2 - 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-circuit 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]

Gas shielded arc welding wire according to the present invention SUMMARY OF THE INVENTION An ultrasonic wire in an organic solvent
After washing and removing the wire body, the pore size of 0.2 μm
Filtration using filter paper (membrane filter)
Ion concentration in the measurement solution obtained by removing the organic solvent
And iron ion concentration in the copper on the wire surface
When the ion concentration and the iron ion concentration are defined as the ion concentration, the copper ion concentration contained in the wire surface deposit is 5000 ppm or less and the iron ion concentration is 500 ppm or less.

Preferably, the copper ion concentration and the iron ion concentration of the surface deposit are not more than 3000 ppm and 300 ppm, respectively.
ppm or less, and more preferably, the copper ion concentration and the iron ion concentration of the surface deposit are 1000 ppm or less and 100 ppm or less, respectively.

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.

[0012] Further, the composition of the solid wire is such that the composition contains 0.01 to 1.80% by weight of Ni, 0.01% by weight.
To 0.70% by weight of Cr, 0.01 to 0.65% by weight of Mo, 0.01 to 0.50% by weight of Al and a total weight of 0.01 to 0.30% by weight of Ti and / or Z
It may contain at least one selected from the group consisting of r.

[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 surface of the wire and the observation result of the welding arc phenomenon photographed by a high-speed camera, it is dissolved in the oil for feeding or rust prevention attached to the surface of the wire. Metal ions (copper ions and iron ions) have been found to interfere with the stable feeding of the wire between the conducting tip and the wire, which makes the arc unstable. Dissolution of metal ions (copper ions and iron ions) in the oil reduces the fatty acids in the oil necessary for improving the feedability and rust prevention, and reduces the distance between the current-carrying tip and the gas shielded arc welding wire. It was found that metal contact was likely to occur at this time, resulting in poor feeding.

For this reason, the present invention regulates the copper ion concentration and the iron ion concentration in the wire surface deposits, but as a result of many experiments by the present inventors, the present invention has found that the copper ions and the iron ions are contained in the gas shielded arc welding wire surface deposits. Copper ion concentration is 5
When the iron ion concentration is 500 ppm or less and the iron ion concentration is 500 ppm or less, the gas-shielding arc welding wire can be fed stably, and the welding arc is broken and the short-circuit between the gas-shielding arc welding wire and the molten pool is short. It has been found that can be reduced.

The effect of preventing arc breakage and short-circuit due to the stable feeding of the wire is further improved by further reducing the copper ion concentration and the iron ion concentration of the surface deposit to 3000 ppm or less and 300 ppm or less, respectively.
The copper ion concentration and iron ion concentration of the surface deposits were 10
This effect is further improved by setting the content to 00 ppm or less and 100 ppm or less.

Means for regulating the concentration of copper ions and iron ions on the surface deposits of the gas shielded arc welding wire depends on, for example, the method of applying oil for feeding or rust prevention. When used in circulation, there are a method of removing a metal fine powder before ionization by installing a filter in a circulation path, and a method of applying static electricity to oil to aggregate and remove ultrafine metal impurities. In this way,
It is possible to regulate copper and iron ions in surface lubricants.

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 wt% Cu is an indispensable element for increasing the electric 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.

The Cu may be present in any state of being plated on the surface of the wire, dissolved in steel or 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 welding arc instability and an increase in cracking 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.

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

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% by weight 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 that Ti be greater than Zr.

[0035]

Next, an embodiment of the present invention will be described. First, a method for measuring the copper ion concentration and the iron ion concentration in the present invention will be described. There are various methods for analyzing a substance adhering to the surface of a gas-shielded arc welding wire (hereinafter, referred to as a wire). The inventors of the present application have determined the most preferable method of analyzing copper ion concentration and iron ion concentration by trial and error. As a result of the investigation, it was most effective to use a method of ultrasonically cleaning the wire in an organic solvent such as petroleum ether to collect and analyze the deposits on the surface.

In 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. The organic solvent is then passed through a filter paper (membrane filter) having a pore size 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 obtained when the organic solvent is no longer detected is used as a measurement solution, and this measurement solution is acid-decomposed. C.
By performing P (inductively coupled plasma) analysis, the copper ion concentration and the iron ion concentration in the measurement solution are measured.

In this case, the obtained measuring solution does not contain an organic solvent, and is composed of only the wire surface adhering matter which has passed through a filter paper having a pore size of 0.2 μm, and has a copper ion concentration and an iron ion in the measuring solution. The concentrations (% based on the total weight of the measurement solution) are the copper ion concentration and the iron ion concentration contained in the wire surface deposits.

Accordingly, the copper ion concentration and the iron ion concentration are not affected by the wire weight and the amount of the organic solvent, and are the most effective method for measuring the copper ion concentration and the iron ion concentration contained in the wire surface deposits. In addition, according to this method, since a wire of several kg or more can be easily analyzed, a trace substance adhering to the wire surface can be collected with high accuracy. The copper ion concentration and iron ion concentration specified in the present invention are 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 concentration of copper ions and the concentration of iron ions contained in the surface deposits are variously changed, and welding is performed on the mild steel base material.
The 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 copper ion concentration and the iron ion concentration 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 8 to 14, welding workability was also evaluated with respect to the results of similar welding performed using solid wires having compositions deviating from claims 4 and 5 of the present application.

[0044]

[Table 1]

In the workability evaluation column, the welding workability was evaluated by sensory and expressed in five levels. 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 apparent from Table 1, Example 1 in which the copper ion concentration of the oil adhering to the surface of the solid wire is 5000 ppm or less and the iron ion concentration is 500 ppm or less.
In cases of to 7, the workability is excellent. That is, the solid wire of this embodiment is fed stably, and short-time short-circuiting between the solid wire and the molten pool and breaking of the welding arc can be reduced. As a result, it is possible to reduce welding defects and improve welding efficiency. On the other hand, in Comparative Examples 8 to 14, the copper ion concentration of the surface deposit was 5000 p.
pm or an iron ion concentration exceeding 500 ppm, the welding workability was low.

[0047]

According to the present invention, the copper ion concentration of the deposit on the surface of the wire for gas shielded arc welding is reduced to 5000 pp.
m or less, and the iron ion concentration is regulated to 500 ppm or less, so that the gas-shielded arc welding wire is stably fed, and a short-circuit between the gas-shielded arc welding wire and the molten pool is short-circuited. Welding arc breakage can be reduced. As a result, it is possible to reduce welding defects and improve welding efficiency.

Claims (5)

(57) [Claims] 1. The wire is ultrasonically cleaned in an organic solvent, and
After removing the main body of the ear, filter paper (pore
Filtration using an organic solvent in the filtrate
Of copper ion and iron ion in the measurement solution obtained by removing
Ion concentration in the wire surface deposits
And a concentration of iron ions, wherein the concentration of copper ions contained in the wire surface deposit is 5000 ppm or less and the concentration of iron ions is 500 ppm or less. 2. A copper ion concentration of the surface deposit is 300.
The gas shielding arc welding wire according to claim 1, wherein the iron ion concentration is 0 ppm or less and the iron ion concentration is 300 ppm or less. 3. A copper ion concentration of the surface deposit is 100.
The gas-shielded arc welding wire according to claim 2, wherein the iron ion concentration is 0 ppm or less and the iron ion concentration is 100 ppm or less. 4. The solid wire comprises 0.001 to 0.15% by weight of C and 0.30 to 1.10% by weight of S.
i, 0.85 to 2.60% by weight of Mn, 0.001 to 0.030% by weight of P, 0.001 to 0.030% by weight of S and 0.01 to 0.50% by weight of Cu 4. A solid wire having a composition comprising iron and unavoidable impurities.
The wire for gas shielded arc welding according to any one of the above. 5. The solid wire according to claim 1, wherein said solid wire comprises 0.001 to 0.15% by weight of C and 0.30 to 1.10% by weight of S.
i, 0.85 to 2.60% by weight of Mn, 0.001 to 0.030% by weight of P, 0.001 to 0.030% by weight of S and 0.01 to 0.50% by weight of Cu Containing, 0.01 to 1.80% by weight of Ni,
0.01 to 0.70% by weight of Cr, 0.01 to 0.65
% Of Mo, 0.01 to 0.50% by weight of Al and at least one selected from the group consisting of 0.01 to 0.30% by weight of Ti and / or Zr, with the balance being the balance. Is a solid wire having a composition consisting of iron and unavoidable impurities.
The wire for gas shielded arc welding according to any one of the above.