JPS5945096A - Welding material - Google Patents

Abstract

PURPOSE:To reduce defects by welding the painted steel plates without removing the paint coated film in the weld zone and to improve welding efficiency, by incorporating specific components in a welding material and incorporating one or both of 1 kind or >=2 kinds among Se, Te, Sb and S which are limited in weight ratios. CONSTITUTION:A welding material produced by incorporating 0.05wt% Ti in steel contg., by weight, 0.15% C, 1.0% Si and <=3.0% Mn and incorporating one or both of 0.005-0.1wt% in total of 1 or >=2 kinds selected from Se, Te, Sb and 0.04-0.1wt% S is used as a coated arc welding electrode, a welding wire for submerged arc welding or further a filler wire and a filler rod for gas shielded arc welding. The reason for limiting the chemical components lies in that if C is contained too much the corrosion resistance is poor. If Si is contained too much, the toughness is poor. A too much content of Mn results in the inferior shape of beads and poor corrosion resistance and machinability.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a welding material used for welding painted steel plates that have been subjected to rust prevention treatment.

Various types of steel structures such as tanks, bridges, ships, and automobiles are subject to the following measures to prevent corrosion during their manufacture or assembly:
In most cases, steel plates are coated with a primer to prevent rust, and then they are cut and welded as appropriate for fabrication or assembly. As a rust prevention treatment at this time, painting with wash primer or zinc-rich shop primer is often performed. Zinc-rich shop primers include organic ones (e.g. zinc dust + epoxy resin, etc.) and inorganic ones (e.g. zinc dust + ethyl silicate, etc.). ,
It has the effect of preventing corrosion of steel plates through the action of zinc dust as a sacrificial anode.

However, if steel plates coated with this type of shop primer are welded as they are, the burning of the resin and the formation of zinc scum will disturb the arc during welding, increase the generation of spatter, and cause pits and blowouts in the welded area. There is a problem in that welding defects such as holes are likely to occur, which may adversely affect the mechanical strength of the welded part.

Therefore, prior to welding painted steel plates, the coating film on the welded area is sometimes removed by grinding, etc., but such removal work is extremely troublesome and time-consuming, so it reduces the construction efficiency of steel structures. This caused a significant decrease in

Therefore, there are attempts to reduce the occurrence of pores such as blowholes by reducing the amount of lead powder in the paint, but even if such a primer is used, it is not possible to prevent the formation of pores. It was a difficult tuna.

This invention was made to solve the conventional problems described in 1-1. The object of the present invention is to provide a welding material that does not cause welding defects such as pin spots or blowholes in the welded parts, has good mechanical strength in the welded parts, and can improve the construction efficiency of steel structures.

The welding material according to the present invention can be used for welding painted steel plates that have been subjected to anti-corrosion treatment. Suitable for use, C: 0.15
% by weight or less, Si: 1.0% or less, Mn: 3.0% by weight or less, (contains as this component, and as necessary Ni, Affl, Co, Zr, W, M
In addition to impregnating Ti: 0.05 to 0.3% by weight into steel containing Cr, etc., one or more selected from Se, Te, and Sb are combined. , O
O5~0, 1% by weight and S: 0.04~0.1% by weight
It is characterized by containing one or both of the following.

The welding material according to the present invention is used as a coated arc welding rod, a welding wire for submerged arc welding,
Furthermore, gas shielded arc welding (MIG welding, TI
G welding, C02 welding, MAG welding, MAG pulse welding, etc.), as welding wire in the case of consumable electrode method.
Alternatively, it is used as a filler wire or filler rod in the case of -Jl consumable electrode method.

Next, the chemical composition of the welding material according to the present invention (weight j11%
) will be explained below.

C: 0.15% by weight or less C is an element necessary to ensure the mechanical strength of the welded part, but if it is contained in a large amount, it will deteriorate the corrosion resistance of the welded part, so the content should be 0.15% by weight or less. .

Si: 1.0% by weight or less' Sl is an effective element as a deoxidizing agent, and preferably i
It is preferable to contain 2% by weight or more of iO. Also, 0
．． A content of 5% or more of the claw portion has the effect of improving arc stability and oxidation resistance. However, if the content exceeds 1% by weight, the toughness deteriorates and high temperature embrittlement occurs, so it is necessary to limit the content to 1.0% by weight or less.

Mn: 3.0% by weight or less Mn is an element that is effective as a deoxidizing agent and also contributes to improving the strength of the weld, and is preferably 0.5% by weight.
It is preferable to contain it in an amount of % by weight or more.

However, if it exceeds 3.0% by weight, the shape of the beet deteriorates,
Since it deteriorates corrosion resistance and workability, it needs to be 3.0% by weight or less.

These two are the basic elements contained in steel, but in addition to that, Ni:o, 5-5 is added to improve strength and toughness.
If necessary, it is desirable to include Mo: 0.1 to 1.0 weight %.

The welding material of the present invention contains Ti in addition to the above basic components, and further contains Se and Te.

Although one or both edges of S and one or more of sb are contained, the reason for limiting the range of these components is as follows.

Ti: 0.05-0.3% by weight Ti is an effective element for improving the arc stability during welding, reducing the generation of spatter, and improving the strength of the weld. 0.0 to get the effect.
05% by weight or more.

However, even if the content exceeds 0.3% by weight, the arc stabilizing effect will be saturated and the mechanical properties of the weld will deteriorate, so the content should be in the range of 0.05 to 0.3% by weight.

Se, Te, Sb and S are elements effective in preventing the generation of pores in welded parts, and Se, Te
, Sb, and one or both of Sb and Sb. When containing one or more of Se, Te, and Sb, the total content is 5% or more in order to obtain the above effects, but if it is too large, the welded part will become brittle and the machine will not be machined. Since it reduces the strength of the target and is also expensive, the combination of these 1; 1 reduces O,L TOTO%.
This is the following. In addition, when S is contained, it is contained in an amount of 0.04,000 i-% or more in order to obtain the effect described in L.
If it is too large, the welded part will deoxidize and the mechanical strength will decrease, so the content should be 0.1% by weight or less.

Examples will now be described.

First, welding wire (diameter) with the steel composition shown in the table.

2 mm) was manufactured, and welding of the fillet part A (not shown in the attached drawing) was performed by pulse MAG welding. The welding conditions at this time were: current 250A, 220 pulses/second, shielding gas (8
0% Ar + 20% C02), and the heat length was 20 cm. The painted surfaces 1a and 2a of the painted steel sheet 1.2 shown in the figure are coated with an inorganic zinc primer containing 40% zinc powder.

Next, each welded part was photographed using X-rays to examine the number of pores, and the same results shown in the table were obtained.

As is clear from the results shown in the table, S, Se, Te
When using a welding wire of the present invention containing one or both of Sb and Sb,
The number of pores in the welded part was extremely small, whereas the number of pores in the welded part was considerably large when welding wire made of a comparative material outside the appropriate amount range was used.

As is clear from the above explanation, the welding material of this invention
When welding coated steel plates using this method, welding defects such as pits and blowholes are extremely small, and the mechanical strength of the welded area is good, making it unnecessary to remove the coating from the welded area. Since there are no holes, it can bring about benefits such as high efficiency in the construction of steel structures.

[Brief explanation of drawings]

The drawing is an explanatory view of fillet welding performed in an embodiment of the present invention. d

Claims (1)

[Claims] (1) C: 0, 15% by weight or less, Si: 1.
Steel containing 0 weight% and Mn: 3, 0% or less is made to contain Ti: 0.05 to 0.3Φ111%, and one selected from Se, Te, Sb or Total of 2 or more types 0.005~O, Lf<ffi%
4. Containing one or both of and S: 0.04 to 0.1Φli4%. Welding material with special characteristics.