JPS608919B2 - automatic welding wire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an automatic welding wire that is not plated with copper or the like.

Generally, the surface of automatic welding wire is plated with copper or the like to improve rust resistance and appearance.

However, on the other hand, plated wires have various drawbacks as follows. (I) There is a risk that rust will enter the weld metal and cause cracks to occur in the weld.

{口i) When the wire is subjected to frictional force in a welding torch, the plating is scraped and becomes powder, which clogs the wire passage inside the torch and makes the arc unstable.

During the manufacturing of wire, pollution is generated by waste liquids such as cyanide.

For this reason, the present inventors investigated and considered various surface treatments that could be used instead of plating in order to eliminate the drawbacks of conventional wires. 0.5% by weight or more of acid amine salt or 0% of carboxylic acid partial ester of polyhydric alcohol
．． 5% by weight or more or 0.5% by weight of both
1. Containing the above, and containing a lubricity improver such as fatty acid, graphite, and molybdenum disulfide. By applying refined mineral oil that contains more than I found that it was greatly improved.

That is, the present invention is based on such technical results and provides an unplated wire that has various superior welding performance than conventional plated wire, and also prevents pollution. .

For wires that are not plated for purposes other than welding, such as wires for ropes, an attempt is made to apply vegetable oil such as rapeseed oil during the final finishing of the wire to give the wire surface shine and provide short-term rust prevention. has also been done.

However, these oils are not suitable for welding wires because they have insufficient anti-corrosion ability and also deteriorate and solidify over a long period of time. In comparison, refined natural oils such as kerosene, spindle oil, and machine oil are sufficiently stable substances and do not deteriorate like vegetable oils. It also has appropriate viscosity and lubrication performance, reducing the frictional force that the wire receives within the welding torch. However, since mineral oil alone does not have sufficient rust prevention ability, adding 0.5% by weight or more of carboxylic acid amine salt or carboxylic acid partial ester of polyhydric alcohol to this mineral oil will dramatically improve the rust prevention ability. Ru. The carboxylic acid amine salt mentioned here is a salt produced by a substance having an amino group (-NH2, =NH, 3N), such as dodecylamine, oleoyl imidazoline, dicyclohexylamine, etc., and a carboxylic acid. An example of the structural formula is as follows. In addition, the carboxylic acid partial ester of a polyhydric alcohol referred to here is an ester of an alcohol having a large number of hydroxyl groups (monoOH) such as sorbitan, monooleate, pentaerythritol, and monooleate with a carboxylic acid, and its chemical An example of the structural formula is as follows. The cause of metal rust is that oxygen and moisture are adsorbed on the metal surface and react with the metal to form oxides.

Therefore, in order to prevent metal oxidation, a protective film can be formed on the metal surface using a substance that has a polar group with very strong adsorption power. For this reason, the carbonyl group of carboxylic acid (one COOR
), refined mineral oil containing polar groups that have a strong affinity for metals, such as the amino groups of amines (1NH2, =NH, 3N) and the hydroxyl groups of polyhydric alcohols (1OH), are applied to the surface of the welding wire. When applied, it forms a protective film as shown in Figures 1 and 2, keeping moisture and oxygen out. In the figure, 1 is a wire, 2 is a polar group, and 3 is a hydrocarbon group. In addition, even if moisture or oxygen is attached to the metal surface first, polar groups such as COOR, which have a strong bond with the metal, will penetrate under the moisture and oxygen molecules due to their substitution effect and lift them to the surface. Demonstrates rust prevention power. Here, the substance with polar groups added to the refined mineral oil only needs to cover the metal surface in a few molecular layers.
It is sufficient if the content is about 0.5% by weight or more. The lower limit of 0.5% by weight is because a sufficient adsorption film cannot be formed with a content below this value. 1. Lubricity improvers such as fatty acids, graphite, and molybdenum disulfide are added to refined mineral oil. Adding more than a wide weight % reduces the frictional force exerted within the welding torch. In other words, if the additive amount is below these lower limits, a homogeneous adsorption film as shown in Figure 2 cannot be obtained, and the film may be partially damaged, making it difficult to achieve practical rust prevention or lubrication effects. You won't be able to get it.

It should be noted that in order to create an adsorption film like the one shown in Figure 2, it is clear that both additives with polar groups and refined mineral oil with hydrocarbon groups are required, so the amounts to be added should be adjusted according to common sense. There is an upper limit, and the value is 5% by weight, as shown in Figures 3 and 4. This is because even if it is added in an amount exceeding 5% by weight, it cannot be expected to significantly increase the antirust effect or the lubricating effect, but it has the disadvantage of increasing costs. In addition, Fig. 3 shows that refined mineral oil contains only sorbitan monooleate (characteristic A) and only dicyclohexylamine salt (characteristic B).
), a mixture of 1'2 each of solvitamin monooleate and dicyclohexylamine salt (Characteristic C) shows the experimental results of investigating the number of rust spots generated when 0.1% to 70% of each was added. It is a diagram.

In addition, Figure 4 shows a mixture of refined mineral oil mixed with 1'2 of sorbitan monooleate and dicyclohexylamine salt (characteristic C), and a mixture of graphite mixed with the mixture (characteristic D) of 0.1 It is a figure which shows the result of the experiment which investigated the lubricating effect when adding ~70%. In addition, in the experiment shown in Fig. 4, the torch shape was 300 and 2
Motor for wire feeding when feeding inside the turn
The lubrication effect was confirmed by changes in the Yuka flow. Next, we actually made unplated wire coated with refined mineral oil containing lubricity improvers such as these carboxylic acid amine salts, partial esters of polyhydric alcohols, fatty acids, molybdenum disulfide, and graphite, as specified by JIS. wet test,
The results of the salt water mist test and indoor storage test are shown in Table 1 below. A wire coated with refined mineral oil containing 50% by weight at a rate of 3 coats per 10kg of wire was found to be 1.5 to 2% lower than conventional plated wire in wet tests and indoor storage tests. It has excellent rust prevention power.

In particular, those containing dicyclohexylamine salts have a remarkable effect in preventing gas phase corrosion, and therefore have good storage test results. In addition, 5. carboxylic acid moiety ester of polyhydric alcohol. A wire coated with refined mineral oil containing 10 kg of wire at a rate of 3 coats per 10 kg of wire has 1.5 to 2.0 times more rust prevention power than conventional plated wire in wet tests and salt fog tests. In particular, those containing sorbitan monooleate have extremely high water displacement properties, and therefore have good wet test results. In addition, when refined mineral oil containing 5.0% by weight of a mixture of carboxylic acid amine salt and carboxylic acid partial ester of polyhydric alcohol was applied at a rate of 3 days per 10k9 of wire, the vapor phase corrosion resistance of both was improved. Due to the synergistic effect of replaceability, conventional plated 2.0
~3. It has M sound rust resistance. Table 1 Rust resistance test results for each F car Note) 1 Refined ore top 11K each contains 5 weight additives.

Note) 2 The amount of coating on the waa is 39 per 10 waa. Next, the lubrication performance of the wire surface was determined by changing the shape of the actual welding torch and determining the magnitude of the motor current value that controls wire feeding. This motor current value changes in proportion to the force required for feeding the wire, and this value is small for wires with good lubrication performance. As a result, as shown in Table 2 below, unplated wires coated with refined mineral oil containing carboxylic acid amine salts or carboxylic acid partial esters of polyhydric alcohols have approximately 50% higher feed rate than conventional plated wires. The load is reduced, and the addition of lubricity improvers such as fatty acids and molybdenum disulfide graphite will further reduce the feeding load. Table 2 Additive K for each jiwata
Next, from the aspect of welding performance, we experimented with various substances with polar groups added to mineral oil. As shown in Table 3 below, compared to other substances with polar groups, carboxylic acid Wires containing amine salts and carboxylic acid moiety esters of polyhydric alcohols have the most stable arc during welding, less spatter, and provide performance equivalent to or better than conventional plated wires. There was no difference in the results when molybdenum disulfide and graphite were added in an amount of 1.0 to 2.0%.

Table 3 Welding performance with various additives In the above examples, the content of carboxylic acid amine salt, carboxylic acid partial ester, or a mixture of both was 5.
．． Although we have only explained the case of 0% by weight, similar results can be obtained if the content is 0.5% by weight or more and 5% by weight or less. Similar effects can be obtained with respect to the agent as long as it is 1.0% by weight or more and 5% by weight or less.

As a result, 0.5% by weight or more of carboxylic acid amine salt or 0.5% of carboxylic acid partial ester of polyhydric alcohol
1. Contains 0.5% to 50% by weight of 0.5% to 50% by weight, or a mixture of both, and 1.% by weight to 50% by weight, and 1. Unplated wire coated with refined mineral oil containing 5% by weight or more and 5% by weight or less has rust resistance 2 to 3 times better than conventional plated wire, and the wire feed It was revealed that the load was reduced by approximately 50%, and the welding performance, such as arc stability and spatter generation rate, was equivalent to or better than that of plated welding.

In addition, since plating is not required, manufacturing costs can be reduced and the risk of pollution can be eliminated, making it highly industrially viable.

[Brief explanation of the drawing]

FIG. 1 is an enlarged cross-sectional view of the wire according to the present invention, FIG. 2 is an enlarged cross-sectional view of the surface of the wire, and FIGS. 3 and 4 are characteristic diagrams showing the effects of the wire according to the present invention. 1...Wire. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1 Carboxylic acid amine salt 0.5% by weight or more and 50% by weight
Contains 0.5% to 50% by weight of the following or a carboxylic acid partial ester of polyhydric alcohol, or a combination of both of 0.5% to 50% by weight, and contains fatty acids, graphite, disulfide, etc. An automatic welding wire characterized in that it is not plated with copper plating or the like coated with refined mineral oil containing 1.0% by weight or more and 50% by weight or less of a lubricity improver such as molybdenum.