DE1521539B2 - Corrosion-resistant wire or rod-shaped material and method for its manufacture - Google Patents

Description

1 2

The invention relates to a corrosion resistance achieve. Since the composite in the solid phase uses a capable wire or rod-shaped material with a minimum of deterioration of the metallurgically connecting surfaces to a core made of rapidly oxidizing material, e.g. steel, and an outer protective jacket, the bond strength is high More from an alloy based on nickel or copper-nickel 5-layer material due to a minimal proportion of the base, the components that create brittleness via an intermediate layer with the core,
It is advantageous to use low-carbon, stainless steels for the production of this material. to use because carbides are not so easy with them

Ropes or cables are usually made of steel - as with the other steels, they are precipitated

strands of different dimensions produced io In addition, stainless steels produce a sufficient

and are stranded after suitable stretching or tensile strength. Furthermore, certain are stainless

braided so that the steels required for the cable are not magnetic, which in some cases

To achieve tensile strength. The strands or wires are cheap.

of such a cable are in the atmosphere. As for the method according to the invention, especially in seaworthy use, due to seawater 15, a deterioration due to upper and the organisms present there of a basket surface oxidation with the formation of chromium oxide exposed to rosion. In order to remedy this situation, what is caused by a chromium content in the rust is avoided known that an austerity-free steel could be produced for each individual strand before the nitic core made of a strong stainless steel composite in the solid phase is achieved. This erod. Like. With a sheath made of copper-nickel 20 are more favorable conditions for the bond, Od. The like. To use the metallurgical, preferred stainless steels as well upon exposure to air in the solid phase, is connected, as is the case with chromium oxide coatings, which - as shown below, for example explained in the USA patent specification 2 753 623 - represent a problem that is difficult to solve, is written. Austenitic stainless steels and the like. Further features and advantages of the invention can be seen However, alloys have chromium components between 25 and 25 given in the following description see 12 and 18%. As a result, carbides are removed from the drawing, the execution, when slow heating or includes examples of the invention. In the drawing shows cooling in the range between 426 to 815 ° C

is carried out. Carbides are for the end Fig. 1 a schematic view of a device

product is harmful because it is a fragility to carry out the process,

cause and, without protection, cause corrosion. 2 shows a cross section along line 2-2 of FIG

speed up. Fig. 1 on a larger scale than this, with a

A method for producing copper plating is already known, indicated by dotted lines,

a multiple metal, with the help of which a basic F i g. 3 shows a section along line 3-3 of FIG. 1 in

plate with a plate containing chromium under pressure 35 on a larger scale than this,

and heat is connected. Before the association, the F i g. 4 shows a cross section along line 4-4 of the at a temperature of about 1093 to 1260 ° C i g. 1 on a larger scale than this takes place, the chromium-containing plate with a position of the finished product.
Layer of a metal that is difficult to oxidize, as in the drawing, 1 is coated with copper over nickel. The heating takes place for 40 drawn cords made of stainless steel for a period of V2 to 2 hours, during the time shown, which, for example, can have a diameter of 7.9 mm, even if the pressure is constantly maintained. This strand is a must. Overall, this type of annealing requires a lot of time to be prepared and then cleaned by immersion in conversion, which in turn requires an acid, which forms an electroplating bath as well as extensive treatment systems, since only one 45, with a relatively low material throughput per time strand before the cleaned one is removed in the acid a thin copper layer 5 unit is possible. That, moreover, only forms in batches. This galvanic deposition means that a process can be used, even if the strand cleaned by the acid is also mentioned in front of it (German patent specification 912 733). The long warm-up time called before taking out in the same acid with copper is also affected by electroplating, so that the precipitation of carbides before the plating is unfavorable to which the air no longer has access to the steel, which affects the adhesive strength of the composite material. rapid surface oxidation to chromium oxide

The invention is therefore based on the object would call. The strength of the copper plating is not

a multilayer, a rapidly oxidizing and critical, besides being of such a size

A corrosion-resistant protective jacket 55 should have holes in which chromium oxide

to create material with which the form could be reduced to a minimum

different parts at relatively low den. So through this process the whole becomes

Temperatures rapidly and preferably continuously Chromium oxide on the surface of the strand when

are connectable to each other. This task is removed when it is brought into the bathroom and replaced by a copper

the material mentioned at the outset according to the Er- 60 surface layer, which then has a

Finding solved that results between the core and protection against chromium oxide formation. Any

the protective sheath an intermediate layer of copper copper oxidation that could occur on the core,

or a chromium-free noble metal would result in copper oxide, which, however, is much slower

and that the core, the protective jacket and the interstitial structures are removed much more easily than chromium oxide

layer metallurgically in solid phase. Furthermore, the copper surface forms the

are connected to each other. With this material, a stainless steel core is an ideal one

A relatively short compression of the metal is sufficient if it is in for the subsequent bond

in solid phase, in order to ensure a sufficient bond to solid phase is pure, with certain copper

3 4

Nickel sheaths provide a favorable diffusion copper-nickel strip before entering the Rezielt cake 11 could have formed. The distance between

With 3 two degreased, cleaned strips are seen from the feed of the pressure rollers 13 and the a copper-nickel alloy referred to, the output of the retort 11 is small, so that a for example a copper-nickel content between 5 and 5 oxidation, which increases slowly during movement 70:30 to 90:10 per cent. These two are in- formed up to the rollers before being pressed together, suitably by cold rolling or the like is also small and can be removed quickly, semi-hard state, for example! Ahart, brought together. The compression is achieved with a reduction in been. The individual strips (Fig. 2) have a range between 10 to 15% carried out, wherein Thickness on the order of 0.305 mm and 10 12% is a preferred size. The result a width of 15.8 mm. Copper-nickel alloys is now that the strips 3 are wrapped around the core relatively low in the galvanic forms and with this under pressure and at one Range of metals and alloys. They are there- no melting-inducing heat in solid be linked forth relatively inactive in seawater and phase. The stripes become outside of the others corrosive environments. In addition, they are in a solid phase with one another along lengthways seats they are connected to strong parts that counteract rotting, which are designated by 23. Properties, since they release copper ions, which are necessary for the pressure rollers 13 have roller contact living organisms are toxic, so that the formation of guide rings 25 and there a small free such organisms on the surface of the strands passage or roller spacing of 0.25 mm or is prevented. Cable, which according to the invention 20 less where the composite at the longitudinal partial strips 23 can therefore be produced more easily. The result is a print of rubbish changed and the tendency towards cracking material 27, which can now, as indicated, fall off, is reduced. It is true that copper-nickel alloys are used. as mentioned above, preferably used, but separating results, so the side edges can through Titanium can also be used. 25 any other suitable and known means

When feeding the parts into the facility to be removed. The finished form of the sheath

according to FIG. 1 slide the strip 3 through electrical is at 29 in FIG. 4 shown.

Contacts 7 and the copper-coated core 1 It is known that a composite in the solid phase

through an electrical contact 9. The with the help of pressure rollers not only a substantial one

Parts then go through a retort 11, in which a 30 reduction during pressure to form a

reducing atmosphere of dissociated Am- so-called green composite requires, but

moniak is circulated. In the absence of a heat treatment (at a temperature

Copper coating, for example at 5 on temperature, below which the liquid phase forms) for

stainless steel, such a reducing improvement in the bond is required. One

Atmosphere at an extraordinarily low 35 such heat treatment can be done during printing

Dew point (for example -51 ° C) can be maintained, or can be carried out afterwards. In the pre-

In order to keep the formation of water to a minimum, the temperature occurs during the

add that the reduction of chromium oxide un- pressure, among other things, because the

favorably influenced. When using a copper strip 3 and the core 1 through the heated retort

jacket, a higher dew point can be used 40 11 have passed through. The heating time is

(for example + 10 to 15 ° C), so that the formation is short and, for example, only 40 seconds or maximum

of water, which, as mentioned, for the least 1 minute. The benefit of this process is found

Reduction of copper oxide has an unfavorable effect easily. The temperature is essentially

could. Such a higher dew point can be sustained considerably until the roll is drawn in,

easier to maintain. , 45 The coated material leaving the rollers 13

The strand 1 moves from the retort 11 and material now enters a retort 31 with a nitrogen atmosphere of a roller frame 15, which faces a water cooling jacket on the strips 3 of the nip of the pressure rollers 13. The cross-sections of the one through which the material rolls during a period of time are at the feeder in FIG. 3 shown. Denoted at 17 through 50 seconds or at most 1 minute is an electrical control device that goes 50. The exit temperature of the material when leaving the retort 21 via lines 19 with the contacts 7 and 9 is of the order of magnitude. A line closing the circuit at 121 ° C. As indicated at 33, a 21 can be connected to one of the rollers 13 as a ground. Water spraying take place in order to achieve a final By a known control circuit of the rapid cooling to about 37 ° C, control device 17 is achieved that flows through 55 whereupon the material is then in a roll 35 on the two strips 3 and the strand 1 through. which then assumes room temperature, these currents preferably flow in such a way that if any undesired side edge piece is set at a temperature of approximately the finished product remains, it can be in the copper-nickel- Strips 3 and in a known manner, for example by cutting off, at a temperature of approximately 982 ° C in strand 1, 60 scraping off, shearing off or the like, removed,
is enough. The most favorable temperature ranges for The great importance of the short heating time in the copper-nickel strips 3 are between 815 of the retort 11 (40 seconds) and the short Kühibis 982 ° C in order to avoid melting. A time of 50 seconds in the cooling retort 31 shows a favorable range for the core 1 is between 843 in that an excessive precipitation of up to 1010 ° C. 65 carbon from the austenitic steel on a

The result is that the dissociated ammonia minimum is reduced. Austenitic, stainless

gas in the retort 11 effectively any steels precipitate carbides when they are either long-

Reduced copper oxide, which slowly heats up on the sam in a range of 426 to 815 ° C

or cooled down. Through the quick passage through this area during heating, pressure bonding and cooling the carbide precipitation is reduced to a minimum and the formation of the so-called sigma phase prevented during cooling. It has already been pointed out above that the preferably used stainless steels with a low carbon content are beneficial. Carbides are for the end product is detrimental in that it becomes fragile cause and accelerate corrosion that can occur at any defect.

The stainless steel of the core 1 is in a fully annealed condition. A structure is therefore a solid one Solution. At a temperature between 1010 and 1038 ° C, this steel would leave its solid solution. Therefore, the temperature in the retort 11 does not reach these values.

Although the layer 5 is made of copper according to the above statements, any one can also be used other metal is used which is suitable for the formation of a bond in the solid phase, but is this advantageously chromium-free. So, for example, silver, gold or can be used any other precious metal.

Claims (15)

Patent claims: 1. Corrosion-resistant wire or rod-shaped material with a core rapidly oxidizing material, such as steel, and an outer protective jacket made of a Alloy based on nickel or copper-nickel, which is connected to the core via an intermediate layer is, characterized in that between the core and the protective jacket an intermediate layer made of copper or a chromium-free noble metal is arranged and that the core, the protective jacket and the intermediate layer are metallurgically connected to one another in the solid phase. 2. wire or rod-shaped material according to claim 1, characterized in that a Intermediate layer of gold or silver is arranged. 3. wire or rod-shaped material according to claim 2, characterized in that the Outer jacket consists of a copper alloy with about 70 to 90% copper and 10 to 30% nickel. 4. wire or rod-shaped material according to any one of the preceding claims, characterized characterized in that the steel contains chromium. 5. wire or rod-shaped material according to any one of the preceding claims, characterized characterized in that the steel does not contain any carbon deposits. 6. wire or rod-shaped material according to any one of the preceding claims, characterized indicated that the steel is in normalized condition. 7. wire or rod-shaped material according to any one of the preceding claims, characterized characterized in that the steel is an austenitic steel. 8. wire or rod-shaped material according to any one of the preceding claims, characterized characterized in that the steel is a low-carbon, stainless steel. 9. Process for the production of a corrosion-resistant wire or rod-shaped Material according to claims 1 to 8 by pressing on, characterized in that the with the core coated with the metal of the intermediate layer with one or more strips of the The metal of the protective jacket is heated in a reducing atmosphere and the strips are underneath a pressure and a temperature on the core and pressed against each other on their longitudinal edges are pressed together with reduction so that the individual parts are in the solid phase join together, the material is then rapidly cooled, with both heating in the reducing atmosphere as well as cooling the material at a time is made for a minute or less. 10. The method according to claim 9, characterized in that the cleaned core on galvanic Ways is coated with the metallic intermediate layer. 11. The method according to any one of claims 9 or 10, characterized in that the core and heating the strip above 815 ° C but below a temperature at which to melt the parts occurs. 12. The method according to any one of claims 9 to 11, characterized in that the core is heated to a temperature in the range between 815 and 1010 ° C. 13. The method according to any one of claims 9 to 12, characterized in that the strips be heated to a temperature in the range between 815 and 982 ° C. 14. The method according to any one of claims 9 to 13, characterized in that a reduction of about 10 to 15% of the material is made. 15. The method according to any one of claims 9 to 14, characterized in that the cleaning and applying the intermediate layer by electrolytic means in an acid bath will. 1 sheet of drawings