DE2322460B2 - Electrode wire - Google Patents

Description

The present invention relates to an electrode material for arc welding, in particular electrode wires for welding and melting of the steels in the inert gas medium. The invention can be particularly effective with automatic and semi-automatic ones Welding used in overhead, inclined and horizontal positions on vertical surfaces will.

There are known electrode wires for welding and melting the steels in the protective gas medium, which represent a steel jacket with a powder-like core arranged in this. The best Technological welding properties are exhibited by electrode wires whose core contains rutile. It is z. B. an electrode wire of the type mentioned (the so-called powder wire) is known, the 55 percent by weight Contains rutile, 16 percent by weight manganese, 14 percent by weight ferrosilicon and aggregates. In the production of this well-known wire, magnetite is used as surcharge, which is in a Amount of 15 percent by weight of the weight of the core is used. The proportion of the steel jacket this wire is 84 percent by weight of the total weight of the wire (see patent specification 34 18 446, Class 219-130, issued in USA).

However, this wire does not ensure good mechanical properties of the weld. So z. B. the impact work at a temperature of + 20 ^ C is only 8 to 9 kgm and at a temperature from 18 "C only 3 to 4 kgm.

When welding a metal covered with rust, pores form in the weld.

It is well known that the mechanical properties of welds are quite unfavorable from that Hydrogen contained in the sweat can be influenced.

The stated composition of the electrode wires does not contain any elements that represent hydrogen to bind in the weld not detachable connections. Therefore the scope is more like this Electrode wires restricted. For example, they cannot be used in constructions that are exposed to dynamic loads, as well as in structures that operate at low temperatures can be used.

An electrode wire is also known which ensures good mechanical properties of the weld and its powder core enclosed in a steel jacket (in percent by weight of the weight of the core) contains:

Rutile 20 to 40

Ferromanganese 10 - = 13

Ferrosilicon 0, e> 2.0

Feldspar 0.6 to 6.0

Fluorosilicate 0.6 to 4.5

Iron powder 37.0 to 68.0

(see GDR patent specification 90 691).

However, the presence of the iron powder in the core of the wire reduces the storage times of the Wire.

The properties of the wire, the core of which is moistened, which leads to corrosion of the iron powder are not restored by glow.

Includes the presence of iron powder that significant amounts of hydrogen and oxygen, in the wire core also substantially increases the porosity of a ₅ sweat, especially in the case where a rusty metal being welded.

The invention was based on the object of providing such an electrode wire for welding and to create melting in the protective gas medium, the core composition of which is the production of good technological welding properties and mechanical properties of the weld in one wide range of welding data and high performance of hardfacing guaranteed as well as the Formation of pores in the seams when welding the metal, especially when welding one with Prevents scale and rust from covered metal.

This task is accomplished by creating an electrode wire for welding and reflowing solved by steels in the protective gas medium, which has a steel jacket with a in this enclosed represents powdery core, which contains rutile, ferromanganese, ferrosilicon and aggregates; the powder-like core of the wire according to the invention contains, in addition to the components mentioned, the, related on the weight of the core, in the following quantities:

Weight percent

Rutile 40 to 75

Ferromanganese 17 to 28

Ferrosilicon 1.8 to 9.5

are used as surcharges:

3.0 to 9.5 percent by weight hematite,
1.8 to 7.5 percent by weight feldspar,

1.2 to 6.0 weight percent sodium fluosilicate.

The presence of the stated amounts of rutile in the powdery core of the invention Wire ensures that the arc burns steadily and that the welds are perfectly formed. We have found that a reduction in the rutile content of the wire according to the invention to below the lower limit mentioned is inadmissible because it greatly impairs the stability of the arc burning and a strong spraying of the electrode metal takes place. When increasing the top The limit remains the melting speed of the

3 4

The core behind the melting speed of the steel material, which is very unfavorable to the mechanical shell back, which affects an enlargement of the shafts of the metal. To resolve the Prevent amount of non-metallic inclusions in the form of hydrogen in the weld of non-melted core particles and sodium fluosilicate in the wire according to the invention thus the properties of the weld metal were significantly introduced within the stated limits. The introduction worsens. The use of an amount of sodium fluorosilicate which is below the amount of ferromanganese and ferrosilicon of the lower limit mentioned does not bring any concern taking into account the warranties. Exceeding the upper limit The performance of good mechanical properties leads to a severe deterioration in stability Sweat set. With those mentioned in the erio of burning the arc and beyond wire according to the invention contained amounts of these to a violent spraying of the electrode metal. Elements are formed in the weld easily melt- The wire with the assemblable according to the invention Iron manganese silicate, which easily coagulates and settles in the core, exhibits excellent technology. The non-gic welding properties remaining in the weld are guaranteed metallic inclusions have a round shape 15 a small amount of gases in the weld as well on. All of this has a positive effect on the impact strength and the high quality of the seams. The by means of the wire Sweat. The seams made are characterized by a high resistance

The reduction in ferromanganese and ferromanganese against pore formation marked. the

silicon content below the specified limit is inadequate- Properties of the wire, the core of which is moistened

casual, because otherwise there were pores 20 in the weld, are heated at temperatures between

form. The amounts of these elements that see the upper 250 and 300 ^r C are restored.

Crossing boundaries causes a significant The chosen ratio between the components

An increase in strength and a reduction in the plastic allow the production of a slag with

sweat. good physical properties. As a result of that

To produce a slag with good physical properties, sodium fluorosilicate is present in the core and that

See properties contains the core of the invention iron powder is missing, it became possible the gas content

proper wire hematite. greatly lower the sweat and increase the resistance

We have proven that lowering the seams prevents the formation of pores and cracks.

of the hematite content below the lower limit.

severe deterioration in the formation of sweat 30 The advantages of the electrode according to the invention

evokes. wire compared to the known be through

This is due to the fact that the slags illustrated in the following examples

Contains only rutile, a very narrow crystalline During the welding process, electrode

have sation area. By wiring such a slag (they are briefly referred to as A, B and C)

quickly crystallizes at the seam surface, prevents 35 with a powder-type designed according to the invention

they prevent the gas from leaking out of the metal. Used on the upper core, the diameter of which is 2.0 mm

The surface of such seams also forms cracks, which one bore. The proportion of the steel jacket was in each

The consequence of the action of the pressure of the gases is that the wire is 84% of the total weight of the wire.

are at the slag-metal interface. The weld was carried out in the overhead position

To expand the crystallization range of 40 by means of a semi-automatic process with

Slag is introduced into the wire core hematite. reversed polarity carried out.

A hematite content of over 9.5% significantly increases sweat data:

the sensitivity of the metal to hot cracking because the welding current is 350 to 450 A.

for the formation of easily fusible intergranular voltage of the arc ... 28 to 35 V.

Contributes to intermediate layers. 45

The presence of feldspar in the mentioned- Carbon dioxide was used as a protective medium,

th quantities in the core increases the stability of the light- The steel to be welded together with a

arc burning and improved technological thickness of 16 mm had the following composition:

Data of the slag. Carbon 0.18 "/ 0

With feldspar quantities below the lower limit 50 manganese 0.45 ⁰ zo

are, the seams have notches, which are not silicon '.'. '. ".'. '.'. '.'. '.'. '.'. '.'. '.'.". '. '.'. 020 ⁰ O

represents permissible error. Sulfur ...................... o | o20 ° / o

An increase in the amount of feldspar to more than 0.015 ⁰ zo phosphorus

the upper limit leads to a deterioration in the ^ _est '''" iron

physical properties of the slag because 55

whose viscosity increases significantly and the raffia

ability to worsen, what is a general wire is listed in the following table 1:

represents my known fact. Table I.

In the course of the welding process, in particular

when welding metal, the electrode wire with scale and 60 components of the core

Rust is covered, is in the zone of the ABC of light

arc a large amount of hydrogen. It's all-

It is common knowledge that hydrogen, which is rutile 75.0 55.7 40.0

at higher temperatures it dissolves in the metal, in ferromanganese 17.0 25.0 28.0

The metal is deposited in the course of crystallization. 65 ferrosilicon 1.9 5.0 9.4

As the rate of deposition of the water- hematite 3.1 7.5 9.4

feldspar 1.8 3.7 7.5 are formed in the sweat

Pores, and there remains a large amount of water sodium fluorosilicate 1.2 3.1 5.7

Results of the test of welds in the seams carried out by means of said electrode wires are.

Table 2

Elek- Tear- Specific- Impact Strength,

Trode-resistance fish notch cruet

wire (kg'mm ⁵ ) elongation (kgm / cm ¹ )

(° / o) + 2O ⁰ C -6O ⁰ C

A. 48 to 52 24 to 28 13 to 15 5 to 6th 8th B. 50 to 55 28 to 32 15 to 20 10 to 12 C. 58 to 62 25 to 28 15 to 17 6 to

Welding by means of wires with cores, the compositions of which are given in the examples are, will be successful after semi-automatic and automatic procedures in overhead, inclined and in a horizontal position on the vertical surface of the seam.

The examples given sufficiently characterize the advantages of the invention Wire.

From Table 2 it can be seen that the welds in the seams made by means of the electrode wires A, B and C have good mechanical properties.

In addition, the wires produced according to the invention ensure excellent formation of the Seams, good separability of the slag crust, with the performance of overlay welding 10 to 14 kg / hour reached. The spraying of the electrode material is minimal. Those carried out by means of the wire Seams are characterized by good mechanical properties, high resistance to pores and Crack formation marked. The wire enables a rusty metal to be welded. The properties of the wire, the core of which is moistened, can be annealed at temperatures between 250 and 300 ° C can be restored.

Claims (1)

Claim: Electrode wire for welding and melting the rods in the protective gas medium, the represents a steel jacket with a powder-like core enclosed therein, which Contains rutile, ferromanganese, ferrosilicon and aggregates, characterized in that in addition to the components mentioned, based on the weight of the core, in quantities Weight percent Rutile 40 to 75 Ferromanganese 17 to 28 Ferrosilicon 1.8 to 9.5 used as surcharges 3.0 to 9.5 percent by weight hematite, 1.8 to 7.5 percent by weight feldspar, Contains 1.2 to 6.0 percent by weight sodium fluosilicate.