JPS596760B2 - Steel wire for arc welding - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a small diameter steel wire used for arc welding, and more specifically, a 2.0 mW wire used for inert gas shielded arc welding, carbon dioxide gas shielded arc welding, submerged arc welding, etc.
An arc that is made of a small diameter steel wire of tΦ or less and has excellent feedability and rust prevention by attaching a rust preventive agent that has functions such as lubrication and rust prevention to the surface of the copper-plated wire. The company provides steel wire for welding.

As automation in various welding operations progresses, various highly efficient welding methods using small diameter wires and high current density have been developed and put into practical use.

In such welding, the melting speed of the wire is high and the wire feeding speed is necessarily high, making it difficult to stabilize the welding arc. If the arc is unstable during welding, it will adversely affect the welding result. In particular, if the conduit tube from the wire feed motor to the welding torch is long, warm, or curved, resulting in a large feeding resistance, this will cause a noticeable problem in wire feeding, causing arcing. In cases where the welding is extremely unstable, it may even be impossible to continue welding. Under these circumstances, conventionally, lubricating oil is applied to the surface of the welding wire at a rate of 0.5 to 2.0 f (V) per 10 kg of wire.

2) Apply esters, soaps, etc. alone or in combination diluted with a solvent such as water, acetone, alcohols, etc.

Although improvements have been made in wire feedability, etc., using wire surface treatment techniques such as those described above, these techniques have the following drawbacks and pose practical problems.

1) The amount of diffusible hydrogen in the weld metal is proportional to the amount of organic substances such as lubricants and oils attached.

The amount of diffusible hydrogen in the weld metal of low alloy high tensile strength steel is 2CC/
100? Since it is said that the following is desirable, the amount of adhesion is 0.1? /1 kg, it cannot be applied to welding this type of high-grade steel material. Furthermore, if welding wire is used with oil attached to it, problems arise in terms of the mechanical performance of the weld metal. Furthermore, a mixture of this oil, dust, welding fume, etc. accumulates in the conduit tube during welding, and over time this actually impedes feedability, and in extreme cases, welding is interrupted. Therefore, it has been necessary to clean the conduit tube at frequent intervals. 2) If a wire wound around a spool or the like is left unwrapped at a work site for several days, feeding performance deteriorates.

3) When applying a lubricating substance diluted with water, water often remains on the wire surface together with the lubricating substance, causing discoloration and rust.

Furthermore, when using other organic solvents, great care is required to prevent ignition and deterioration of the working environment, and maple ventilation equipment is also required. In view of the current state of conventional arc welding solid wires, there is a desire for a wire that satisfies the following conditions.

In other words, regarding feeding performance, the wire can be fed stably under any severe conditions during welding, even when the conduit tube is long and has to be bent due to a narrow worksite, and even when feeding at high speeds. In addition, it must be excellent in two conditions regarding rust resistance. In other words, it must be able to withstand long-term storage (usually 1 to 2 years) in its original packaging, and it must be able to withstand being stored for a long time (usually 1 to 2 years), or for several days after opening (welding must be interrupted and the wire set in the welding machine before the next work is carried out). It is to withstand exposure (if left untreated). Excellent rust resistance means that there is no sign (or trace) of discoloration or rust under the above two conditions, and that the feeding and lining performance that was exhibited immediately after manufacture can be maintained for a long time. And this is an absolute condition. The present invention can fully satisfy the above-mentioned conditions, and has 0.0
40 to 80% by weight of oil-soluble amine and 20 to 20% of rust preventive oil are applied to the surface of the copper-plated wire to a plating thickness of 5 to 0.15 μm.
A rust preventive agent consisting of 60% by weight was added at a rate of 0.0% per kg of wire weight.
The gist of the present invention is a steel wire for arc welding characterized by having a thickness of 0.05 to 0.10'.

Examples of the oil-soluble amine of the present invention include stearylamine (Cl8H38NH2) dimethylstearylamine (R
Examples include aliphatic amines such as -N(?) and diamine (RNH(CH2)NH2).

These oil-soluble amines act as adsorption inhibitors to improve the gloss of the copper-plated surface, and the bonding state between the amine and the metal is the arrangement between the high electron density of the nitrogen atom and the metal electrons. By forming positional bonds, oil-soluble amines form a strong chemisorption layer on the metal surface, suppressing reactions at both the anode and cathode simultaneously. As a result, excellent rust resistance can be achieved over a long period of time with a small amount of coating. On the other hand, examples of antirust oils include vegetable oils such as palm oil, tallow, and mineral oils.

This anti-rust oil and oil-soluble amine are easily mixed, and just by applying a small amount to the surface of the wire, the feedability is improved and the rust-resistant young fruit is exhibited.

The mixing ratio of the oil-soluble amine and rust-preventive oil that constitutes the rust preventive agent is 40-80% by weight of the oil-soluble amine and 20-6% by weight of the rust preventive oil.
Both are mixed at 0% by weight to make 100%.
If the oil-soluble amine is more than 80% by weight and the rust preventive oil is less than 20% by weight, the rust resistance and feedability will deteriorate and the arc will become unstable.
On the other hand, if the oil-soluble amine is less than 40% by weight and the rust preventive oil is more than 60% by weight, the rust resistance will deteriorate. In the present invention, a rust preventive agent consisting of 40 to 80% by weight of the oil-soluble amine and 20 to 60% by weight of rust preventive oil is applied to the surface of the product wire at a wire weight of 11% by weight.
<0.05 to 0.10' per g. Adhesion amount is 0
If D5I1k9 is less, the wire feedability during welding will be poor and the b arc will become unstable. Rust resistance also deteriorates. 0
．． If it exceeds 12/1k9, is the amount of diffusible hydrogen in the weld metal 2CC/1001? Illusionary high tensile steel that exceeds
It cannot be used for welding low alloy steel, etc.

Next, the reason why the copper plating thickness of the wire was specified to be 0.05 to 0.15 μm will be described. It is generally known that the current copper plating thickness of wires is in the range of 0.4 to 1.0/Tm, and that long-term storage is possible if the thickness is 0.5 μm or more. The copper content in the weld metal is not only that contained in the wire but also copper added by copper plating. The amount added increases as the plating thickness increases and the wire diameter decreases. Although a thin wire with a diameter of 2.0 mm or less is thin, the amount of copper transferred from the copper plating is greater than the copper content of the wire itself. According to JIS standards, the amount of copper in coated arc welding rod core wire is 0.2% or less for Type 1 No. 1 and Type 2 No. 1;
Although it is specified as 0.3% or less in Type 2 and Type 2 No. 2, there are no regulations regarding the copper content of wires for inert gas shield welding and carbon dioxide arc welding. However, generally 0.05 (
fl), so the copper content of the wire should be 0.05% and the thickness should be 0.4 to 1.0μ.
Calculating the copper content in the weld metal when m is 1.6
For mmΦ, it is 0.17 to 0.35%, and for 1.2 mmΦ, it is 0.20 to 0.44%. Recently, from the viewpoint of neutron irradiation embrittlement in nuclear reactor structures (pressure vessels), it has been said that it is desirable for the copper content in the weld metal to be 0.1% or less, but as mentioned above, the current copper-plated wire is 0.1% or less. Since the plating thickness is 4 to 1.0 μm and the copper content in the weld metal exceeds 0.1%, it is not preferable to apply it to pressure vessel welding. The welding thickness must be 0.15 μm or less, but with conventional wire surface coating agents, the wire plating thickness is 0.15 μm or less.
The following products cannot withstand long-term storage in normal packaging conditions, and it is impossible to prevent discoloration and rust even if exposed for a short period of time. On the other hand, the rust preventive of the present invention has sufficient rust resistance even when the plating thickness is 0.4 to 1.0 μm or less than Ql5 μm. However, if it is less than 0.05 μm, the rust resistance deteriorates, so the copper plating thickness of the wire is specified to be 0.05 to 0.15 μm. That is, a steel wire for arc welding with a plating thickness of 0.05 to 0.15 μm is coated with a rust preventive agent consisting of 40 to 80% by weight of an oil-soluble amine and 20 to 60% by weight of a rust preventive oil on the wire surface. Although it is extremely thin at 0.05 to 0.15 μm compared to conventional wires, it has sufficient rust resistance and the copper content in the weld metal is less than 0.1%, making it suitable for use in nuclear reactor structures (pressure Good welds can be obtained when welding containers). Next, the present invention will be explained in detail based on examples.

First, the relationship between the mixing ratio of the oil-soluble amine and rust preventive oil constituting the rust preventive agent and the wire feedability and the rust resistance will be described. In Fig. 1, I is a wire diameter of 1.2 Φ, a rust preventive agent with various mixing ratios of oil-soluble amine and rust preventive oil,
Steel wire with plating thickness of 0.15μm (CO.O8%
lO. 75%, Mnl. 6O(Ff)) wire 1 on the surface
The wire feedability when 0.08' of wire was deposited per kg was investigated by measuring the load current value of the wire feed motor.

The load current value of this wire feed motor is small for wires with good feedability, and high for wires with poor feedability. However, the temperature of the wire is 20℃ with the package open.
, humidity of 800/) for 10 days. In the figure, A is an oil-soluble amine (stearylamine), B is a rust preventive oil (palm oil), and the oil-soluble amine is 8
It can be seen that if it exceeds 0% by weight (if the rust preventive oil is 20% by weight), the load current value of the wire feeding motor increases and the feeding performance deteriorates.

Alternatively, apply 0.08 t/kg of wire to the surface of a wire with a wire diameter of 1.2 mm and a plating thickness of 0.15 μm using a rust preventive agent with various mixing ratios of oil-soluble amine and rust preventive oil, and then open the package. The wire was left in an atmosphere with a temperature of 3'C and a humidity of 90%, and the number of days until discoloration and spots of rust appeared on the wire surface was determined. It is clear from the figure that when the oil-soluble amine is 40 to 80% by weight (the rust preventive oil is 20 to 60% by weight!), the number of days for discoloration and spot rust to occur is 7 to 8 days. It can be seen that the rust resistance is poor when the mixing ratio is other than the above. The relationship between the amount of rust preventive applied and wire feedability is shown in Figure 2.

A rust preventive agent containing 60% by weight of oil-soluble amine and 40% by weight of antirust oil was attached to the surface of a wire with a diameter of 1.2 mm and a plating thickness of 0.15 μm, and the load current of a wire feed motor that would not damage the weld was measured. The relationship between the amount of rust preventive agent deposited on the wire surface and wire feedability was investigated. However, the condition of the wire was the same as in the case of Fig. 1, and it was left unpacked in an atmosphere with a temperature of 20°C and a humidity of 80 (fl) for 10 days, and the welding conditions were also the same as in the case of Fig. 1. be. As is clear from the figure, as the amount of rust preventive agent attached increases, the load current of the wire feed motor decreases, and when it becomes 0.052/11<g or more, it shows a very stable value. As an example of this measurement result, Figure 3 shows that the amount of rust preventive coating is 0.0052/
1k9,0.02t/11<9,0.08t/1kg shows the load current fluctuation situation, which is 0.08t/1kg.
It is clear that 1k9 is extremely stable. The feedability test shown in Figures 1 and 2 above is shown in Figure 4.
This was done using the equipment shown in the figure.

That is, the wire 6 wound around the spool is pressed by the feed roller 1, and the conduit tube 2 of about 3 m length
The wire is fed to the welding torch 3 through a 1-turn loop 5 of 00mmΦ, and an arc is continuously emitted to the steel plate 4 rotating in the direction of the arrow 4'' to continue welding, and at the same time, the load current of the wire feed roller 1 is recorded in direct current balance. Next, the relationship between the amount of rust preventive agent deposited on the wire surface and the rust resistance is shown in FIG.

A rust preventive agent containing 60% by weight of oil-soluble amine and 40% by weight of rust preventive oil was applied to the surface of a wire with a diameter of 1.2 mmΦ, and the wire was left unwrapped in an atmosphere at a temperature of 30°C and humidity of 90%. The number of days until discoloration and dotted rust appeared on the surface was investigated. It is clear from the figure that the coating amount of D rust preventive agent is 0.05'/1
It can be seen that if the weight is 0.05 μm or more and the mating thickness is 0.05 μm or more, the number of days for discoloration and spot rust to occur is 7 to 8 days, indicating that the material has sufficient rust resistance. Next, the rust preventive agent used in the feedability test shown in Figure 2 (oil-soluble amine: 60% by weight, rust preventive oil: 40% by weight)
(CO.O9%, SiO.63%,
Mnl. 9l%, MOO. The amount of diffusible hydrogen in the deposited metal when welding is determined using JIS Z3ll3-1
Measured based on 970.

The wire used here has a wire diameter of 1.2Φ, a plating thickness of 0.15 μm, and an amount of rust preventive coating on the wire surface of 0.02'/11<G,O. ．． O5'
/1kg, 0.10t/1k9, and 0.12'/1k9, and the results of welding using these wires and measuring the amount of diffusible hydrogen in the deposited metal are shown in Table 1. . As is clear from Table 1, the amount of rust preventive applied is 0.1
It can be seen that if it exceeds t/1 kg, the amount of diffusible hydrogen increases significantly, which is not preferable.

As detailed above, the steel wire for arc welding of the present invention improves wire feeding performance during welding, and maintains quality immediately after manufacture without causing surface changes such as discoloration or rust even if left for a long time. In addition, the amount of diffusible hydrogen in the weld metal can be significantly reduced.

Furthermore, the plating thickness of the wire can be made extremely thin at 0.05 to 0.15 μm, and the copper content in the weld metal can be reduced, making it an excellent material suitable for welding nuclear reactor structures (pressure vessels). play the fruit.

[Brief explanation of drawings]

Figure 1 shows the relationship between the mixing ratio of oil-soluble amine and rust preventive oil in the rust preventive agent and the load current of the wire feed motor, and the relationship between the number of days for discoloration and rust spots to occur. is a diagram showing the relationship between the amount of rust preventive agent deposited on the wire surface and the load current of the wire feed motor, Figure 3 is a diagram showing the change in load current for three examples in the experiment shown in Figure 2, and Figure 4 is A schematic diagram showing the feedability test equipment shown in Figures 1 and 2, and Figure 5 shows the relationship between the amount of rust preventive coating on the wire surface and the number of days for discoloration and spot rust to occur, using the copper plating thickness as a parameter. FIG. 1...Feeding roller, 2...Conduit tube, 3...Torch, 4...Steel plate, 5...Loop, 6 ...Wire wound around a spool.

Claims (1)

[Claims] 1 A rust preventive agent consisting of 40 to 80% by weight of oil-soluble amine and 20 to 60% by weight of rust preventive oil is applied to the surface of the copper-plated wire to a plating thickness of 0.05 to 0.15 μm for 1 kg of wire weight.
A steel wire for arc welding, characterized in that 0.05 to 0.10 g/g is deposited.