DE1943025A1 - Welded construction made of a copper-nickel alloy - Google Patents

Description

■■ 1943025 Dipl.-Ing. H. Sauerland ■ Dr.-Ing. R. King Patent Attorneys · 4000 Düsseldorf · Cecilienallee 76 · Telephone 43S7as

Our file: 25 178 August 22, 1969

International Nickel Limited, Thames House, Millbank, London, S, W. 1 , Great Britain

"Welded construction made of a copper-Niokel alloy"

■ f

The beneficial properties of copper-nickel alloys with 25 "to 35% nickel are well known. Avg Addition of one or more elements such as niobium, silicon, aluminum, titanium, beryllium, iron can these alloys are hardened to increase their hardness and strength noticeably. To these alloys that can reach a yield strength of at least 35 kg / mm after hardening, some recently developed alloys with 29 to 33% nickel include, 1.25 to 1.55% niobium, 0.2 to 0.4% silicon, 0.5 to 1% Iron, 0 to 0.1% carbon, 0.5 to 1.5% manganese, 0 to 0.05% titanium and 0.15 to 0.35% aluminum, the remainder including melting-related impurities copper.

When welding such hardened copper-nickel-Le *. Alloys arise difficulties, especially with the aforementioned niobium-containing alloy. The weld metal between the parts to be welded together should be just as strong as the parts themselves, but the strength is the weld seam when using a filler metal in MIG welding or a core of a covered one Electrode with a composition corresponding to the composition of the cured parts to be welded together noticeably increased immediately after welding

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less than the strength of the base material. This is due to the fact that the desired hardness can only be achieved through a curing can be achieved.

Post-welding curing is usually difficult and often extremely uneconomical and impractical or, especially with large welded constructions, also practically impossible.

The invention is based on the surprising finding that in welded constructions made of hardened copper-nickel alloys of the type in question can be achieved solid and healthy welded joints, if that Weld deposit has a certain composition. As a result According to the invention, a weld metal of $ 28 to $ 35 Nickel, 1.6 to 2.6% niobium, max. 0.8 $ silicon, 0 to 2 $ iron, 0 to 0.1% carbon, 0 to 4 x $ manganese, 0 to $ 0.5 titanium and $ 0 to $ 0.2 aluminum, the rest inclusive Impurities caused by the mining of copper defeated. Such a weld metal is achieved without hardening generally a yield strength of at least 38.5 kg / mm across the cross section of the weld seam.

In the weld metal, the nickel ensures the corrosion resistance, for which 30 $ nickel is completely sufficient. Niobium carries contributes most to strength, so the niobium content must be $ 1.6 to $ 2.6, and preferably $ 1.9 to $ 2.4.

The weld metal can be welded without impairing the strength Contains silicon up to $ 0.8 when welded. At a Increasing the silicon content from 0.2 or 0.3 to 0.8 $, the toughness of the weld metal is somewhat reduced, see above that the silicon content preferably does not exceed $ 0.6 ",

The manganese combines with the sulfur in the sweat

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and prevents the formation of a coherent and au Phase with low melting point leading to weld cracks. The weld metal can be used without affecting the technological Features up to $ 4 hangan included.

In order to avoid weld porosity, the weld metal Contains aluminum. However, this has no noticeable effect on strength while over 0.2 # aluminum lead to weld cracks.

The iron content should be at least $ 0.3, since iron is known to contribute to the good corrosion resistance of the copper-nickel alloys in question. However , a sieve content in excess of 2f> increases the tendency for weld cracks to form.

Bas weld metal may also contain carbon, which is considered to be Contamination of the various alloy components in the filler metal, the core wire or the cladding • Is borne. The carbon content is said to be like this, however be as low as possible and not exceed 0.1 #, there when the carbon bonds easily with the niobium.

The weld metal can also get up to $ 0.5 titanium from deoxidation contain. In this order of magnitude, the titanium has no significant effect on the properties of the Weld metal.

It is known that commercial niobium is usually low Contains quantities of tantalum, which in this way also gets into the weld seam as an impurity. Tantalum represents however, it is not an equivalent of the nlob and results in weld cracking if its content exceeds $ 0.2.

The alloy according to the invention can be used as an additional metal

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with MIG welding or as core wire of a sheathed Use electrode. To this extent, the invention includes both the filler metal, the core wire and the core of a covered electrode and the covered electrode itself a.

The filler metal of the present invention consists of $ 28 to $ 35 Nickel, $ 2.1 to $ 2.7 niobium, $ 0.2 to 0.8 silicon, $ 0 to 296 iron, $ 0 to 0.1 carbon, $ 0 to 4 manganese, $ 0 to $ 0.5 titanium and $ 0 to $ 0.25 aluminum, the rest inclusive heat-related impurities copper. The additional metal advantageously contains at least $ 0.3 each Iron and silicon. If you were to use the filler metal as the base material, it would be just one without hardening Achieve yield strength of 28 kg / mm, which is well below the required value. On the other hand, the filler metal normally has an excess of 38.5 kg / mm after welding. increasing yield point. .

When used as the core of a jacket electrode, the alloy consists of 28 to 35 $ nickel, 0.8 to 2.7 $ niobium, 0.2 to 0.8% silicon, 0 to 2 $ iron, 0 to 0.1 $ carbon ; 0 to 4 $ manganese, 0 to 0.5 $ titanium and 0 to 0.35 $ aluminum, the remainder including impurities caused by melting copper. The casing in this case consists essentially of 10 to 40 $ calcium carbonate, 5 "to 40 $ cryolite, 2 to 11 $ niobium, Ό to 30 $ manganese carbonate, 0 to 8 $ titanium dioxide, 0 to 2 $ silicon, 0 to 2 $ , $ 5 titanium, $ 0 to $ 3.5 aluminum, and $ 0 to $ 5 bentonite.

There must be flat or horizontal, vertical and overhead weld seams be laid, for which a good electrode is suitable; must. Independent of the respective weld seam position it is essential to avoid damaging perspiration porosity. A criterion for a sufficiently low po-

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Rosity consists in the fact that it is 150 cm long and 12.5 mm wide weld seam has no more than 20 pores. It was found that to avoid a harmful Porosity regardless of the welding position Electrode should contain a small amount of aluminum, although the weld deposit does not contain more than $ 0.2 aluminum may hold. Aluminum also allows efficient transfer of the niobium from the electrode across the arc in the sweat. The aluminum can get in the cladding and / or located in the core, the aluminum contents of the core and the cladding in the following manner on top of one another should be coordinated:

Aluminum in the cladding Aluminum in the core

3.5 until -Ir 4th 0 0 0.05 1.4 until 1 0., 05 until 0.1 1 until O, 6th 0.1 until 0.15 0.6 until 0, 2 0.15 Ms 0.2 2.2 until 0 0.2 until 0.35 0 until

Both the cladding and the core must contain niobium, otherwise weld cracks will occur. However, the total niobium content should not exceed $ 12. That's how it lies Niobium content of the core at $ 2 to $ 2.7 if the cladding Contains a maximum of $ 8 niobium.

Additional metal and core must contain at least 0.2? S silicon, to allow the alloy to be hot worked into wire. Silicon also serves as a deoxidizer and keeps the sweat flowing, making the welder's job easier. Core wire and filler metal should therefore contain at least 0.3% silicon, while the aluminum in the filler metal does not provide any advantages. To-

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The spare metal and core can be used as impurities without damage still contain small amounts of other elements. To the However, harmful impurities include lead, antimony, wiemut, tin, sulfur and phosphorus, of which the alloy preferably not more than O, OO5 # each or in total $ 0.01 lead, antimony and bismuth, no more than 0.01 tin or no more than $ 0.002 each or no more than a total of $ 0.005 sulfur and contains phosphorus as these elements are both the Impair both cold and hot deformability of the alloy. .

In a particularly preferred electrode, the core is made from $ 29 to $ 33 nickel, $ 0.8 to $ 1.55 niobium, $ 0.2 to $ 0.4 silicon, $ 0.5 to $ 1 iron, $ 0 to $ 0.1 carbon, $ 0.5 to $ 1.5 manganese, $ 0 to $ 0.05 titanium, and $ 0.2 to $ 0.35. Aluminum and the coating of $ 22 to $ 26 calcium carbonate, $ 22 to $ 28 cryolite, $ 3.5 to $ 9.5 niobium, $ 20 to $ 26 manganese carbonate, $ 4 to $ 6 titanium dioxide, $ 0.6 to $ 1.5 silicon, 0 ,8th to $ 1.6 titanium and $ 2 to $ 5 bentonite.

During welding, the calcium carbonate develops carbon dioxide, which protects the sweat sump against oxidation by the atmosphere. It also forms a slag component that helps clean the weld metal by removing the sulfur and the welds during cooling ens shields from the atmosphere.

The amount of calcium carbonate in the coating determines various characteristics of the electrode, which range from 22 to 26 $ calcium carbonate achieve optimal values. If the coating does not contain enough calcium carbonate, there will be too little Protective gas is developed and the weld metal is slightly oxidized. Excessive calcium carbonate contents lead to formation small pearls on the electrode tip and premature Melting off the cladding, thereby exposing the core.

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This results in difficulties and high losses Alloy elements of both the cladding and the core; In addition, the resulting slag becomes powdery and is difficult to remove.

The cryolite acts as a refining element in the welding slag. He helps remove oxides from the Weld in so that the weld seam is free of inclusions and slag. Cryolite content from 22 to 28% make the slag easily removable and result in a optimal combination of burn-off speed and viscosity and a minimum of weld spatter, exceeding one of the aforementioned salary limits leads to a premature melting of the cladding, thereby exposing the core.

The titanium oxide stabilizes the arc and leads to a spraying metal transition, which is the case with coated electrodes is extremely desirable. This allows changes in the arc, i.e., the distance between Electrode tip and workpiece so that the welder does not have to move the electrode unnecessarily. The titanium oxide content the coating is preferably about 4 to 6%. Larger or lower contents make welding difficult and result in an extremely unfavorable slag, in particular when laying vertical or overhead welds. '

The manganese carbonate primarily facilitates the removal of the slag layer. It also develops at the Welding additional carbon dioxide, which serves as a protective gas. The decomposition of the manganese carbonate leads to a Increase in the manganese content of the sweat, but it has an effect the increase in the manganese content does not affect the properties of the weld seam. The casing preferably contains

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8AD ORIGINAL

wise 20 to 26 # manganese carbonate, especially when welding of pipes.

The silicon of the cladding improves the fluidity of the Slag and weld metal; it also serves as a des-

Oxidizing agent for the welding metal. The silicon can are usually introduced as a nickel-silicon alloy with a silicon content of $ 30. Contains the wrapping below 0.696 silicon, difficulties arise during welding, which can be transferred to the weld seam. Silicon levels above $ 1.5 make both the welds as well as the slag more liquid than necessary and result in a sticky and difficult to remove slag.

The titanium of the casing serves as a deoxidizer and can be introduced in the form of a nickel-titanium alloy. Titanium content outside the preferred content limits from $ 0.8 to $ 1.6 can result in poor meltdown, heavy splash and a slag that is difficult to remove.

Generally the weight of the envelope is $ 35 to $ 45 the electrode weight. The envelope can by means of conventional Process, in particular by extrusion, are brought onto the core. Bentonite is a colloidal clay and improves the compressibility of the coating compound. In addition, the coating composition can, as usual, use sodium silicate as a binder contain.

The following are the percentages of three different wrappings listed:

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Table I. A.
«■■" • ■ MB 4th B. C. 4th 24 24 '28 Kai zi um carbonate 24 24 20th Cryolite 7th 5.7 7th niobium 23 9 23 23 9 Manganese carbonate 5 3 5 5 8th Titanium dioxide 2.1 - aluminum : o. 0.9 0. silicon 1. 1.3 0. titanium 3 3 3 Bentonite

The invention is explained in more detail below on the basis of exemplary embodiments:

example 1

Between two 12.5 mm thick and firmly with one 5 cm thick A V-seam was placed on the plates clamped to the support plate. The bracing of the two plates prevented them from being movement during welding and promoted cracking. The plates were cured and made of an alloy with $ 1.34 niobium, 0.34% silicon, 0.08% aluminum, 0.81% Iron, 0.8% manganese and 29.95% nickel, the remainder essentially Copper. The plates were under the TIG method Use of a 2.4 mm thick additional wire with 2.4696 Niobium, 0.34% silicon, 0.04% titanium, 0.71% iron, 0.81% manganese and 30.1% nickel, the remainder essentially copper welded together. The final composition of the weld was 2.21% niobium, 0.23% silicon, 0.046% aluminum, 0.028% titanium, 1.1% iron * 0.92% manganese and 28.5% nickel, The remainder is essentially copper.

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The weld seam was faulty, especially cracked, slag- and pore-free. Tensile specimens were machined from the weld seam immediately after welding.

The tensile specimens had a tension spring across the welding direction

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stiffness of 65 kg / mm, a yield strength of 43 kg / mm and an elongation of 13.5%. The break occurred in the heat affected Zone of the plates. A sample consisting entirely of weld metal had a tensile strength of 68.5 kg / mm, a yield strength of 51 kg / mm and an elongation of 19% and a notched impact strength of 5 kgm.

A 6 mm thick sample could be pulled over a mandrel with a Bend a radius of 12 mm over 180 °. After bending could no defects are found on the sample.

Example 2

Substantially similar results were obtained with the achieve the plates described in Example 1 than this with a filler wire of the same composition, the diameter of which was 1.5 mm, were welded by the MIG method. The weld contained $ 1.98 niobium, 0.35% silicon, 0.03% titanium, 0.72% iron, 0.85% manganese and 30% nickel, the remainder being essentially copper.

Example 3

Even better results were achieved when welding the under Example 1 described plates with an additional wire of the same Composition, but can be achieved with a diameter of 0.7 mm in short arc welding. the The weld seam was healthy and of exceptional quality. Their composition was 2.34% niobium, 0.31% silicon,

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«■ 11 -

0.04 * titanium, 0.7 * iron, 0.859 * manganese and 30.296 nickel, The remainder is essentially copper. A transverse sample had tensile strength of 68.2 kg / mm, a yield point of 44 kg / mm, an elongation of 14 »5 *» its break point was in the heat-affected Zone of the base material. The tensile test of the

The weld seam, on the other hand, had a tensile strength of 70 kg / now, a yield point of 48.2 kg / now and an elongation of 26 * with a notched impact strength of 6.4 kgm.

Example 4

A V-butt weld was made with a covered electrode between two in a vertical position 9.5 now thick plates made of a hardened alloy with 1.5 * niobium, 0.27 * silicon, 0.13 * aluminum, 0.58 * Elsen, 1.01 * Manganese and 30.9 * nickel, the remainder being essentially copper. The core of the electrode consisted of 1.42 * niobium, 0.23 * Silicon, 0.25 * aluminum, 0.6 * iron, 0.85 * manganese and 30.4 * nickel, the remainder essentially copper; consequently it had a composition consistent with the Flatten and a coating according to composition A in table 1.

Little difficulties arose when laying the Welding and removing the slag between the passages was just a light lift and brush with a wire brush required. The weld seam contained 2.04 * niobium, 0.46 * silicon, 0.08 * aluminum, 0.95 * Iron, 2.1 * manganese, 0.04 * titanium and 30.1 * nickel, the remainder essentially copper; she was healthy and pointed to one Length of 15 cm has only three pores. Tensile specimens taken across the weld had a yield strength of

ρ Ο

44.3 kg / mm, a tensile strength of 63.3 kg / mm and a Elongation of 16.5 *; their break point was in the heat affected zone of the plate. This experiment shows the excellent

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«12 -

Seichneten properties of the electrodes according to the invention when welding in a constrained position as well as the need for a Enclosure containing aluminum in the case of an aluminum-containing one Core wire.

Example 5

Between two hardened plates with 1.34 $ niobium, 0.17% silicon, 0 »215 ^ aluminum, 0.67 # iron, 1.12? Έ manganese and 3Ο, 59δ nickel, the remainder being essentially copper, an overhead VS weld seam placed. The coated electrode consisted of a core with 2, O59 & niobium, $ 0.28 silicon, $ 0.21 aluminum, 0.85c iron, $ 0.84 manganese, $ 0.05 titanium and # 30.7 nickel, The remainder was essentially copper and a coating * of composition A in Table I. The weld seam consisted of 2.196 niobium, 0.4596 silicon, 0.04 # aluminum, 1.02 $ iron, 2.145 ^ manganese, 309S nickel and 0.04 $ Titanium, the remainder essentially copper.

The quality of the machined weld seam was extremely good. It had only 12 pores over a length of 15 om on. A transverse test showed a tensile strength in the tensile test

p ρ

speed of 64 kg / mm, a yield strength of 42.3 kg / mm and ^ an elongation of $ 159, the break being in the thermo-™ flow zone of the plate. The notched impact strength of the weld seam was 3.9 kgm.

Example 6

Between two of the plates described in Example 5 was Another suture was placed overhead, but using an electrode with a core of $ 2.12 niobium, $ 0.3 Silicon, 0.73 # iron, 0.85 # manganese, 30.5 # nickel and $ 0.01 titanium, res, t consisted essentially of copper while the coating of the composition in B of Table I

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spoke. The weld seam analysis showed 2.52 $ niobium, 0.76 $ silicon, $ 0.18 aluminum, 1.253 * iron, $ 2.25 manganese, $ 30 Nickel and $ 0.08 titanium, the remainder essentially copper.

The quality of the machined weld seam was excellent. It had only three pores per 15 cm. This attempt shows, moreover, that this is necessary to avoid welding porosity during overhead welding Addition of aluminum both in the cladding and in the core can be done.

Transverse samples of the visual weld had a tensile strength of 64.5 kg / mm, a yield strength of 41.8 kg / mm and a Elongation of $ 13.0; the break point was in the heat affected zone of the plate. The impact strength was in the weld seam 2.8 kgm.

Example 7

Between two further plates according to Example 5 was one Third overhead weld seam made using an electrode whose core is made of 1.27 $ niobium, Q, 27 $ silicon, $ 0.095 aluminum, $ 0.079 iron, $ 0.73 manganese and $ 30 nickel, The remainder consisted essentially of copper. The wrapping contained $ 24 calcium carbonate, $ 23 cryolite, $ 23 manganese carbonate, $ 5 titanium dioxide, $ 7.4 niobium, $ 0.9 silicon * $ 1.3 titanium and $ 0.5 Aluminum. When examining the weld seam, around ten small marginal pores were found over a length of 15 cm. This again shows that a small amount of aluminum added both in the core and in the cladding Reduced sweat porosity.

The effect of aluminum on visual cracking and the requirement to limit the aluminum content in the weld to a maximum of $ 0.2 is shown by the results of

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Try where butt welds are on hardened and niobium-containing plates were placed, all under 0.1 $ aluminum contained «, the aluminum and niobium contents of the filler metal and the covered electrodes were different. The weld seams became sample discs worked out and examined for weld cracks. The results obtained are summarized in Table II.

Table II

niobium
($> aluminum Sweat
seam Result 2.05 additive
metal 4.0.05 crack free TIG 1.34 0.08 crack free Sheathed electrode 2.05 0.24 0.15 crack free TIG 1.34 Oo 18 0.24 various
dene 'klei
ne cracks Sheathed electrode 2.72 0.52 0.8 strong
cracked TIG 0.86

Although the electrodes and filler metals according to the invention are particularly suitable for welding hardened copper-nickel alloys, they can also be used for welding other copper-nickel alloys with about 30 $ nickel and high strength. For example, it was possible to achieve excellent results with an additional wire according to the invention on plates made from an alloy with $ 3.75 chromium, $ 0.05 silicon, $ 0.79 iron, 0.55 $ Mafigan, 29.0 % nickel , 0.1? Ί titanium and 0.11 ^ zirconium, the remainder being essentially copper. The filler wire was composed of 2.07 $ niobium, 0 _s $ 33 silicon ^ $ 0.8 iron, 0.2 manganese $ '

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30.1% nickel and 0.09% titanium, the remainder essentially copper. A transverse sample had a tensile strength of 55.6 kg / mm, a yield point of 36 kg / am and an elongation of 13.5% with a notched impact strength of 10.5 kgm.

It turned out that tantalum is not an equivalent of JUiobs in experiments with tantalum-containing filler wires when welding hardened plates made of an alloy with 30.9% Fickel, 1.5% niobium, 1.01% manganese, 0.27% silicon and 0.58% Iron, the remainder essentially copper. The compositions of the additional wires result from the following table III, the alloy residue in each case consisting of copper ".

Si Ni Tabel III Ti Pe Ta
I et ι 0.22
0.24
0.22
0.26 30.7
30.8
31.3
30.5 0.03
0.04
0.04
0.04 0.77
0.71
0.76
0.72 0.42
0.68
1.50
0.45 Mn Nb 0.77
0.83
0.73
0.79 1.54
1.58
0.37
2.67

All the welds were cracked.

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Claims (13)

International Nickel Limited, Thames House, Millbank, London, S. W. 1, Great Britain, SSSSS5S5 * SSb 2SS SSE SEE SSS SSS ■■■ SSb ^ ZSSSb SSh SSa SSS ^ SSSSSSS. SSE Sä »SSSSiS> SSb SSäSSS SES SES SES SSS SSS Patent claims: 1. Welded construction made of a copper-nickel alloy with a yield point of at least 35 kg / mm, characterized in that the Weld seam made of 28 to 35% nickel, 1.6 to 2.6% niobium, a maximum of 0.8% silicon, 0 to 2% iron, 0 to 0.1% carbon, 0 to 4% manganese, 0 to 0.5% titanium and 0 to 0.2% aluminum, the remainder copper including melt-related Impurities. 2. Welded construction according to claim 1, characterized g e k e η η ζ e i c h η e t that. at least one component Made of a hardened copper-nickel alloy containing niobium consists. 3. Welded construction according to claim 1, characterized G e k en η z ic h η e t that at least one component from an alloy with 29 to 33% nickel, 1.25 to 1.55% niobium, 0.2 to 0.4% silicon, 0.5 to 1% iron, 0 to 0.1% carbon, 0.5 "to 1.5% manganese, 3/4 to 0.05% titanium and 0.15 to 0.35% aluminum, the remainder including melt-related Impurities is made up of copper. 4. Additional metal for making a weldment according to Claim 1, characterized in that g e k en η ζ e 1 c h.n e t, that it consists of 28 to 35% nickel, 2.1 to 2.7% niobium, 0.2 to 0.8% silicon, 0 to 2% iron, 0 to 0.1% carbon, 0 to 4% manganese, 0 to 0.5% titanium and 0 to 0.25% aluminum, the remainder including melt-related impurities copper. 009843 / 1T69 ~ 17 « 5. Additional metal after. Claim 4, characterized in that there is at least $ 0.3 iron and contains at least $ 0.3 silicon. 6. core wire for a covered electrode for producing a weldment according to claim 1, characterized marked that he was from $ 28 to $ 33 Nickel, 0.8 Ms $ 2.7 Niobium, Q, 2 to 0.8 $ Silicon, 0 to $ 2 iron, $ 0 to 0.1 carbon, $ 0 to 4 manganese, $ 0 to $ 0.5 titanium and $ 0 to $ 0.35 aluminum, the remainder including smelting-related impurities made of copper. 7. core wire according to claim 6, characterized in that that it contains at least $ 0.3 iron. 8. core wire according to claim 6, characterized in that it contains at least $ 0.15 aluminum. 9. core wire according to claim 8, characterized. marked, that it contains at least $ 0.2 aluminum. 10. core wire according to claim 6, characterized in that that it consists of $ 29 to $ 33 nickel, $ 0.8 to $ 1.55 niobium, $ 0.2 to $ 0.4 silicon, $ 0.5 to $ 1 iron, $ 0 to $ 0.1 carbon, $ 0.5 to 1.5 manganese, $ 0 to $ 0.05 titanium, and $ 0.2 to $ 0.35 aluminum, the remainder including copper there is impurities caused by the melting process. 11. core wire according to claims 6 to 10, characterized in that it is provided with a sheath from 10 to 40 $ calcium carbonate, 5 to 40 $ cryolite, 2 to 11 $ niobium, 0 to 30 $ manganese carbonate, 0 to 8 $ titanium dioxide, 0 098 4,? / 1 169 O Ms $ 2 silicon, O Ms $ 2.5 titanium, O to $ 3.5 aluminum and there is 0 to 5 $ bentonite and that much aluminum contains that the aluminum content of the weld seam is at most Is $ 0.2. ' 12. Core wire according to claim 11, characterized in that that its aluminum content is based on the aluminum content of the casing as follows: Aluminum content Wrapping
($) 1 , 4 the until 1 3.5 Ms 0 , 6 1.4 until 0 , 2 1 until 0 0.6 until 0.2 0 Aluminum covered
of the core wires s
($) 0 0.05 until 0.1 0 until 0.15 0.05 until 0.2 0.1 until 0.35 0.15 until s eke η η 0.2 H d a d u r c 13. core wire according to claim 12, draws that its serving is from $ 22 to $ 26 Calcium carbonate, $ 22 to $ 28 cryolite, $ 3.5 to $ 9.5 niobium, $ 20 to $ 26 manganese carbonate, $ 4 to $ 6 titanium dioxide, $ 0.6 to It consists of $ 1.5 silicon, $ 0.8 to 1.6 titanium and $ 2 to $ 5 bentonite. 0098437116s