JPS6264496A - Seamless flux cored wire for stainless steel welding - Google Patents

Abstract

PURPOSE:To better arc state and the droplet transfer and to reduce spatters by filling the flux containing the specified quantity of metallic component in the inner part surrounded by the sheath composed of a stainless steel pipe by specifying the slag component content in the flux. CONSTITUTION:The flux containing >=59wt% metal component for the whole flux is filled to the inner part surrounded by the sheath being composed of austenitic stainless steel pipe. the filling is performed so that the slag content in the flux becomes 4.5-9.5% for the total weight of a wire. Accordingly, the time lag in the melting of the wire sheath and containing flux is reduced to make the arc state and droplet transfer performance better and the generation of the spatter and slag contamination is reduced.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a 7-layer choir for stainless steel welding that does not have an opening around the circumference, and more specifically relates to a 7-layer choir for stainless steel welding that does not have an opening around the perimeter. This invention relates to a seamless 7/F tuxed shear wire that has good droplet transferability and allows for a diamond-shaped hemorrhoidal weld with less svantal formation.

[Prior art] As shown in Fig. 1, the seamless flux choir has no openings around the outer skin and has a circular symmetrical cross-sectional shape with no directionality. The demand for these wires has been increasing in recent years, as they have many advantages such as excellent wire performance, wire feedability, and straightness of the wire.

In the field of welding materials for stainless steel, flux choirs are being put into practical use to take advantage of the above-mentioned advantages of seamless wires.

However, the general characteristics of seamless wire and stainless steel wire are as follows:
As disclosed in Japanese Patent Application Laid-open No. 49-123140, in the 7':j-containing choir, the # contact current flows only to the outer surface of the wire.

There is a problem in that as a result of the delayed bath melting of the flux in the core, the legs of the arc move around, causing the arc to become rounded and the concentration of the arc to deteriorate.

This problem was solved in the same publication by optically grasping the flux having a coarse grain size (L, 8 to 100 grains) in the built-in 72 grains. In the case of seamless 7-lux rewires, compared to general 7-lux choirs, this phenomenon is much more pronounced and becomes an even more serious problem, depending on the usage and manufacturing method. However, the problem could not be solved by adjusting the particle size of the built-in 7:7x as disclosed in the same publication.

In other words, a seamless 7 lux choir is usually
After filling 7 sixes into an o-size with an outer diameter of 7 to 14 mm and a wall thickness of 1 to 3 mm, the wire is drawn to 1.6 mm.
Although it is manufactured by reducing the diameter of the product to φ or 14 mmφ, the reduction in feed during this time is more than $1d90, and the built-in flux is also compressed by the drawing force.

Furthermore, in the case of stainless steel welding materials, the difference between the outer stainless steel component and the target weld metal (14 components) must be fully adjusted, and a large amount of alloy material must be added to compensate for the wear and tear of the alloy component due to welding. Since it must contain M, the 72x filling standard must be higher than that of a general 72x sifter.

In addition, when austenitic stainless steel FI14 is used as the outer stainless steel, due to its high Roe hardenability, it is photo-annealed (1050 ℃ × 30 minutes).

In principle, it is possible to use mild steel or 7-elite stainless steel for the outer skin, but since the difference between the outer skin component and the target weld metal component will be even larger, %72Tx-filled austenitic stainless steel is used. In the case of steel shell9
The wire must be made larger than the above, and the outer skin (area) must be made small, so wire breakage is likely to occur during the wire drawing process, and welded metal J! ! This method cannot be applied to Meiyo-do because of the large dispersion and fluctuation of the four components.

As mentioned above, the seamless flux choir for stainless steel welding has a high optical emissivity of 7/F, has a high degree of compression after filling, and has been heat treated at temperatures of 10 (70°C or higher) several times. Therefore, the internal organs have an extremely dense and hard structure, making them difficult to melt.

In addition, the outer skin shape is a simple circle.

7 in the center of the wire due to fc not having a complete conductor in the center.
No arc is generated in the boot part, and the welding current flows only to the outer skin.Furthermore, since the outer skin of stainless steel has a large electrical resistance, the outer skin will melt more quickly due to Joule heat generation.

Therefore, in the case of seamless 72x shear wire for stainless steel, f′i, the time difference between the melting of the outer stainless steel and the inner door 7x becomes larger.
The f:il phenomenon of unstable arcs, frequent occurrence of spatter, and fire failures such as slab entrainment is a problem that cannot be compared to a general 7-rank choir.
1 yen, which was a serious problem.

The invention should solve the problems mentioned above. 1.2
mm, 1.0 mmb or smaller, stainless steel/less mm contact mi seamless 7 lux-containing wire can reduce the time lag in melting between the wire outer sheath and the inner R7 lux, thereby reducing arc-shaped M% droplet transfer. To provide a seamless 7-piece choir for stainless steel welding, which has good properties and can reduce the amount of spatter and bag entrainment.

[Means for solving problems]

The gist of the present invention is to place 72x, which contains metal components of 59% or more relative to the entire 7x, in a circular part surrounded by an outer skin made of austenitic stainless steel pipe. is 4.5 for the total wire Xt
This is a seamless 72x-filled choir for stainless steel welding that is special in that it is filled to a content of ~9.5%.

The present invention provides a seamless 7-layer choir for stainless steel welding, although the arc stability, concentration, and transferability of the arc are particularly inferior to that of a general 7-layer choir.
Is the built-in 7 lux subjected to severe toning processing? This is due to the fact that it has become extremely hard and stiff due to the heat treatment, so the time delay in melting the 7-piece part against the outer skin during bathing becomes much longer. To improve it, use a comb that melts the built-in flux itself.

Is it safe to speed up the melting timing? ″1
．． This is based on new knowledge that it is effective to include a large amount of metal powder such as a deoxidizing agent in the 721.72x.

[Effect]

The present invention will be explained in detail below along with its operation.

First, 5US304L steel nose was used as the outer skin.

Flux light 94 rate and slag components (oxides, fluorides) lid! Wire equivalent to JIsZ 3323 YF-308L (1.2 mm) Seamless flux wire gold is manufactured.
(DO 几P 20 ox, 31 V 1 30 c
Carbon dioxide arc welding was carried out under the SI conditions of an/rnln, and the factors affecting the welding workability were examined in detail.

In addition, in this case, the 7 lux light army in the wire is 9 to 2
Changes were made within a range of 8%.

As a result, it was found that the amount of spatter generated tends to decrease as the amount of slag components in the wire decreases, and the arc condition is particularly influenced by the amount of metal components in the built-in 7 lux. It was found that the concentration and stability of the particles increased, and the particle size of the droplets became smaller.

That is, Fig. 2 shows the relationship between the amount of slab components in the wire and the amount of spatter generated. It has become clear that the amount of spatter generated decreases as 4) decreases.

This means that the wire with a low lid containing slag components in the wire is
72 Tx light 914' 4 or 7 slag component content is low, and the proportion of non-conductive @ material in the wire cross section is reduced.
The reason for this is thought to be that the dense flow was substantially reduced. The amount of spatter generated was determined by collecting the spatter generated during welding in a steel valley and weighing it.

In addition, Figure 3 shows the relationship between the metal component content in 7nonox and the maximum droplet diameter during welding. It has little to do with the amount of water, but is greatly influenced by the amount of metal components in the filled 7 lacs, and when the amount of metal components is small, the droplet diameter can reach up to 1 m.

In contrast to the extremely unstable arc condition where the point of arc generation is not constant and there is an arc sound of knocking/clattering,
As the metal component content in the flux increases, the droplet diameter gradually becomes smaller, and as the metal component content in the flux increases, the droplet size gradually decreases.
It has been found that when the arc is blown to 59% or more, the droplets are extremely fine and the droplet transfer form is mostly spray-like, resulting in an extremely stable arc state with uniform arc sound.

By the way, the arc of these wires; the dog evil view festival is ltl! i5
! The maximum droplet diameter in Fig. 3 was determined from a high-speed photographic film of 3000 frames (3 seconds).

The phenomenon in which the arc condition is improved by increasing the content of metal components in the 7 lux can be understood as follows.

In other words, oxides and heptadides are generally used as components that form slag, but among these, fluoride and N
Alkali gold N oxides such as ano and KzO have a significant effect on slag physical properties and arc conditions, so their usage is necessarily limited, and slag is 8IOhTrOhZr.
The product is composed of oxides such as O*, ALaOs*MgO, etc. However, all of these main component oxides have higher melting points than the stainless steel/skinless steel, and this is thought to be the cause of the time lag in melting between the stainless steel skin and the internal flux mentioned earlier. .

A large amount of metal powder with a relatively low melting point enters between these oxide particles with a relatively low melting point, and the metal itself becomes strong. As a result, the entire 7 lux is extremely easy to melt.

It is thought that the time difference between melting with the outer shell is almost eliminated, the protrusion phenomenon of the haflux columns disappears, and droplet migration and arc conditions are improved.

The present invention is based on the above experimental results, and the reason why the metal component content in 7 lacs is limited to 59 or more is because, as mentioned above, if it is less than 959%, the arc state, shape, and droplet transferability will deteriorate. It depends. Also, the total weight of the wire is
The reason for limiting the amount of the slag component to 4.5 to 9.5 is that if the slag component t is 4.5%, the slag t will be insufficient, and the encapsulation of the slag will be uneven. If it exceeds .5%, not only will spatter increase as mentioned above, but also the 7 lux light*i' in the wire will have to be increased in consideration of the metal content. This is because the thickness of the outer skin is inevitably thin, and troubles such as cliffs and cracks occur easily during the wire drawing process.

In addition, in the present invention, the metal component is 1. Usually stainless steel @
Nl %Cr, Mo, Nb %W used for
Alloying agents such as O, deoxidizing agents such as At, Mn%T1, etc., ferroalloys containing these components, iron powders, stainless steel powders, etc., especially iron powders, stainless steel copper powders, ferroalloys, etc. They are conveniently classified according to their component compositions in order to organize the metal components in the seven shoes.

In addition, the slag component refers to oxides other than the above metal components,
Refers to non-metallic components such as compounds, specifically td 5i02
．． 'rio= , Zr0z , klxOs ,
FeO%MgO, Oak.

Mn01Na20. K2O, LI20%UaFz,
It means NaF, etc., and raw materials actually used in the formulation include silica sand, rutile, chiku/white, zirnin salado, alumina, soda ash, potassium feldspar, fluorite, etc.
In addition to the above components, these raw materials also contain impurities such as P and s.

In the present invention, a seamless 72x shear wire and d,
It refers to a flux wire without an external opening as shown in M1 Prisoner, and is generally manufactured by drawing a pipe filled with 72Tx as mentioned above, but it is made of a sheathed hoop material filled with flux. It is also possible to manufacture by welding the joints.

In any case, the present invention is a wire manufactured through a wire drawing process with an area reduction rate of 90% or more and at least one sintering process (static specific heat treatment No. 8) after being filled with flux before reaching the product diameter. When applied to 9JJ, the increase is significant.

In addition, in the present invention, the upper limit of the metal component content in 7 lacs was not particularly determined, but in the wire extension work 8
7 lux in the wire from the viewpoint of preventing a! X rate is 30
% or less, and therefore, the upper limit of the metal component-containing lid in the 7 sixes is necessarily about 85%.

[Example J The effects of the present invention will be specifically explained below with reference to Examples.

Austenitic stainless steel 6' with the composition shown in Table 1
Using eve, the gold h4 component word in 72x; tfi
■Change the slag component content in the wire.

JIS Z3323 YF- with a diameter of 1.0 to 1-6 mm
3081, YF-309L, YF-316L compatible wire? Manufactured and all failure gas arc welding in a downward position on a 5LJS304L steel flat plate under the bath welding conditions shown in Table 2,
The weldability of each was compared.

In addition, the wire is Flux Mitsukaki Kaso product Cζ light X30
mrn) was carried out.

In addition, the flux used was Jp granulation in water glass before Kotaka, and the slag component was N brought from water glass.
Also included are ano, KzO, and stow.

The results are shown in Tables 3 to 5 for each wire diameter, and the wire pigeons 7, 8, 9, 10. The droplet diameter was large and the arc condition was unstable.

Mano, wire pigeon 7 with low slab component Nf content in the wire
In the case of No. 1 and No. 11, the arc condition was good, but the amount of slag was small and the encapsulation was poor.

The slag could not uniformly cover the bead light surface.

Furthermore, wire m6 with a high content of slag components in the wire
, 8, 24.25, there were many 51E children due to sputtering. In particular, in the case of wire N116, which had a high slag component content and a relatively high flux flux rate, wire breakage also occurred during the wire drawing process to reach a wire diameter of 1.0 mm.

On the other hand, the metal component content in the flux is high,
In the case of the 27 non-inventive examples in which the slag component in the wire is appropriate, the arc condition is good.

Most of the cases showed droplet transfer in the form of a spray, and there were few fish that produced 9 ivy in one drop, and there were no problems with slag envelopment.

Demonstrates extremely good welding workability.

In addition, the welding work a evaluation in Tables 3 to 5 is ◎:
Very good, Q: good, △: slightly poor, 1x: poor.

Table 1 Table 3 (Wire diameter 1-0mm) Table 5 (Wire diameter 1-6mm) [Effects of the invention] As described above, the present invention increases the metal content in the built-in flux, Furthermore, by suppressing the slag component content for the entire Jijt within an appropriate range, we are able to reduce arc conditions, droplet migration, spatter generation, etc., which have been particularly problematic in conventional small-diameter seamless flux choirs for stainless steel. This made it possible to make improvements.

[Brief explanation of drawings]

Figure 1 is a water exchange diagram of the cross-sectional shape of the seamless flux wire, Figure 2 is a diagram showing the relationship between the slab component in the wire and the amount of spatter generated, and Figure 3 is the metal in the flux. It is a figure showing the relationship between component content and the maximum droplet diameter in #cherry blossoms. 1... Outer skin, 2... Flux. Agent: Patent attorney Hikaru Akisawa and 2 others

Claims (1)

[Claims] (1) A flux containing a metal component of 59% by weight or more based on the total flux is placed inside the outer skin made of austenitic stainless steel pipe so that the slag component content in the flux is 4.5% based on the total weight of the wire. ~9.5%
A seamless flux-cored wire for stainless steel welding, characterized by being filled so that