DE1294681B - Process for producing a hard superconducting alloy with an increased critical current density - Google Patents

Description

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The invention relates to a method for fabricating atoms during heat treatment Position of a hard superconducting alloy with the alloy results. In the main the particles precipitated by the dispersion secondary phase have increased critical current density, hardening. ■ their composition and / or size in the

Under a superconducting metal or a selected precipitation annealing temperature over time superconducting alloy is understood to be such a changeable. Under different conditions Substance, which is below characteristic critical, the phase could consist of particles, their to-values of temperature, current strength and magnet composition is invariable over time, whose field any detectable resistance for electrical quantity, however, at the selected precipitation glow current flow loses. As a parameter for measuring io temperature is variable with time. This last one Superconductivity of a metal or a named particle corresponds to the equilibrium alloy the critical current is used. Composition with the selected precipitation The high current carrying capacity of superconducting temperature. Again under different conditions Substances can be used anywhere where electromagnets could eventually form a mixture in the secondary phase can be operated at low temperatures, 15 of the two phases mentioned above, used to generate magnetic fields. In the German Auslegeschrift 1233 962 is single. Likewise, this high electrical conductivity can help achieve the desired excretion all such cases beneficial application fin- phase in the general form by procedural den, where energy transmission lines are delimited at low or treatment indications, without specific Temperatures can be operated. The ao marking the composition of the said Increase in the critical current density and thus the elimination phase.

Current carrying capacity, of a superconducting substance.

fes has the advantage that the scope or set elimination phase is in a selected one Space requirement of the critical to achieve a given class of hard superconducting alloys Current density required apparatus 35 den, which is an improvement of the current conduction essential decreased. In the case of an electromagnet, such superconductors are caused. This is supposed to go through can be a certain predetermined magnetic field choice of a certain starting alloy and strength and a certain magnetic field volume is reached with treatment according to a special process Achieve an apparatus of smaller size. will. These selected according to the invention

An object of the invention is to provide a 30 and treated alloy intended for a current process to increase the ability to carry current under superconducting conditions a hard superconducting alloy, which is at least an order of magnitude higher Superconducting conditions. Further through the ver is than that of differently composed and / or drive according to the invention an alloy with superconducting not treated in this way improved superconducting properties are created, 35 alloys.

whose current carrying capacity is below its criti- According to the invention, in the method for

see temperature and magnetic field strength as essential production of a hard superconducting alloy is increased, which allows a superconducting solenoid with increased critical current density in the way pre-improved Properties to produce. Finally gone that an alloy made of metals should be a superconducting alloy with improved 40 from one or more of groups III, IV, V, VI, Properties according to the method according to the invention VII, VIII, IVa, Va and VIa of the periodic can be created. Systems (corresponding to the 1956 edition of the

The term "hard" superconductor denotes a "Webster's New Collegiate Dictionary") consists, im Class of superconducting alloys whose superconductive liquid state is added as oxygen, carbon, 45 nitrogen or hydrogen admixed, the so obtained Magnetic field is gradually destroyed in the tene mixture at a temperature below the In contrast to a so-called "soft" supra-melting point of the alloy to achieve a Head that homogenizes the additive evenly when it reaches its critical magnetic level field quite abruptly into its normal resistance and the homogenized alloy thus obtained condition returns. 5 »formation of a finely divided excretion phase,

In the one which does not belong to the state of the art and which contains the additive mentioned, is annealed, German Auslegeschrift 1233 962 is a process on which the alloy then in its dimensions to increase the critical current density of a »har- is deformed to a desired wire size, th «superconducting alloy described in According to a preferred embodiment of the

According to a certain selected superconducting invention, an alloy, the structure of which consists essentially of an oxide, carbide, hydride or nitride of the general single homogeneous phase, of a separating formula MX , in which M is a metal, is used as an additive , annealing in the multiphase range of equivalency whose electronegativity is smaller than the electroweight diagram at a temperature and while the main alloy component is subjected to a period of time that is sufficient for the metal to form. The reduction of the dimensions of the alloy annealed around the precipitation of a secondary phase within the invention, which therefore contains the mentioned induced precipitation phase of the volume of the homogeneous basic structure. The process used there can be carried out in such a way that the separation concerns the production of a secondary knife of the annealed alloy in a non-mechanical phase, which is reduced from the initial homogeneous 65 nischen way to a value below the phase of the treated alloy . of which the critical current density of the precipitating secondary phase comprises the product, the alloy containing the manure phase by mechanically in the rearrangement of the homogeneous basic see processing or precipitation annealing treatment.

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ment can no longer be increased. The designation point cooled and to achieve an equation »electronegativity« is here and in the following distribution of the added impurity in that of L. Pauling in his book »The homogenized. The homogenized alloy Nature of the Chemical Bond, Cornell University mix is then used in a sense defined below HomoPress, 2nd edition. Further advantages and details of the invention glow, which results in a uniformly finely divided output from the following explanation of precipitation in the entire structure of the alloy. will. It turns out that in this way “. _ _n,. ... .....,,. hard superconductor treated according to the invention a

Influence of the precipitation _{annealing treatment 10 has a critical} current density which is around a magnitude. Generally speaking, it is known that the order is higher than that of a superconductor which is not treated in this way to produce the metals and alloys.

which form hard superconductors, a function of the In practice, superconducting materials become part of it so-called interstitial impurities are usually produced in the form of wires that become soles Metal, these impurities from the group of noids or electromagnets of any shape Carbon, oxygen, and nitrogen can be used. Let it be pointed out here-hydrogen exist, and indeed it is so, shown that the critical current density of supradass as the amount of contamination increases, the conductive alloys are increased by cold working Manufacturability of such metals and alloys can be. For example, the cold weight loss mediates. You will almost certainly have deformation of superconducting alloys like them established that in such cases the presence is necessary in order to bring them into wire form, such impurities have a detrimental effect that can be wound into solenoids, which in on the physical and mechanical properties- this way treated alloy has a higher degree th of the material obtained as the end product. of superconductivity. However, in those cases where the Before the invention, therefore, the precipitation phase mentioned in those skilled in the art went into superconducting leaufs the field of hard superconductor alloys is produced, their metallurgical Herin the way before that one always the starting material positional history a cold deformation after the as pure as possible and has this high induction of elimination, can Degree of purity throughout the manufacturing process determine that the superconducting properties of the process tried to maintain. 30 type cold worked alloys by at least

The invention is based on the discovery that, instead of avoiding the presence of such impurities - an improvement that is solely attributable to improvement - an order of magnitude greater than that of cold processing, they are added by deliberately adding them. According to a preferred embodiment, when combined with a heat treatment, the invention also provides a method for producing a hard superconductor containing these impurities, which contains the desired precipitation phase, a profound and over-precipitation phase and their earlier rapid increase in the critical current density of the metallurgical manufacturing history mechanical respective super-hard processing treatments treated in this way, such as a ladder. Expediently, the aforementioned die cold forging can have the desired precipitation phase before the formation of the contamination of the relevant selected hard 40.
Superconducting alloy in the form of oxide, carbide, Ni As mentioned above, it is to be expected that the

trids or hydrides of one of the alloy metals for the introduction of oxygen according to the invention, carbon. If the oxygen, carbon, fuel, nitrogen or hydrogen is added in bound nitrogen or hydrogen in the form of a metal form or in unbound form, whereby according to the compound M (O, C, N or H), the critical current density should be 45 according to the invention which preferably relates to the metal of the connection to a surrounding superconducting alloy, have lower electronegativity than the metal which primarily makes this alloy constituent capable of being manufactured or processed. Of course- superconducting alloy adversely affected. Borrowed it is also possible and is within the scope of this reason and because the worsening of the invention, the manufacturability or processibility leading to the precipitation on the one hand and impurities in unbound form, the increase in the critical current density on the other hand, i.e. the impurity of a certain alloy - Generally with different speeds as gaseous oxygen, nitrogen or water goes on, it is not possible with complete hydrogen or as elemental carbon added accuracy a certain concentration range can be. However, this type of addition offers 55 for the respective additive, which leads to practical difficulties, since it is difficult to allow the improvement of the critical current density of the treated additive in terms of quantity with the desired or delten alloy without checking the required degree of accuracy. Alloy completely unsuitable for processing

To do the basic induction operations. In some cases it may be possible tion of the pronounced increase in the critical 60 to several thousand parts, for example one Current density with the help of a certain amount of the certain oxide or carbide for improvement the additive causing the precipitation must be added to the superconductivity of the alloy, exceptionally well simple. In the liquid state, there is still sufficient manufacturability and control a hard workability composite according to the invention is maintained so that the so made superconducting alloy, which said 65 treated alloy blank into a desired certain content of an excretion her- shape and size can be processed. That's why Contains leading additive. The result obtained in this way is intended to be used in cases where the beneficial effects are obtained Alloy mixture is then under its melting the cold processing with the favorable effects

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one illustrated the desired elimination phase, which leads to a wire of elevation Seeks to combine an alloy that has a smaller diameter than that in FIG. 1 guide the formation of the desired excretion and 2 wires shown is processed; the critical one phase required amount of the respective additive den- current density of these small diameter wires Do not exceed the amount that shows a full 5 in comparison with the critical current density ligen impairment of manufacturability or deterioration in the FIGS. 1 and 2 wires shown, not only workability of the alloy treated in this way. the effect of excretion

To the problem of processability, as there are additives on the critical current density, but can also recognize through the addition causing the precipitation that the dimensions of the wire are equal can, to avoid or at least largely io if a direct influence on the critical current going reduce, one can have the superconductor density; this "dimensional effect" becomes Manufacture using powder metallurgy processes. described in detail below. If, for example, the superconductivity of a

The niobium-zirconium superconductor alloy increases the amount of information about the cold deformation of the should, by adding zirconium oxide in sufficient quantity to 15 superconducting wires to the percentage transverse, to the critical current density of the alloy cut reduction of the precipitation annealed by the formation of an oxide-containing excretion sample. The cold forming or other To increase phase, one can make the alloy in the mechanical processing effected cross-way produce that one zirconium powder with cutting reduction stands to the diameter of the Niobium powder in the desired amounts together with a sample heat-treated according to the invention in folmit either niobium oxide or zirconium oxide homogeneous gender relationship: mixes. The mixture thus obtained is then through

a high-temperature-resistant mold for the formation of a cross-section reduction = 1 - (* -) * -100,

of a wire of the desired dimension hot Wo /

extruded. Then the oxide containing 85 LJ

Separation phase by annealing the alloy at where d _{0 is} the initial diameter of the alloy to be deformed at a temperature in the range from 200 to 1000 ° C, d _{f is} the final diameter of the first alloy to be deformed, preferably in the range from 800 to 1000 ° C.

be procreated. At the higher temperatures, the measurements of the critical current density on the

the precipitation phase, even if the heat-deformed wire samples were in all cases treatment is only briefly carried out in finely divided liquid helium at 4.2 ° K, namely Shape exist, which is to achieve maximum supply with one of a superconducting magnet in took the critical current density of the treated direction transverse to that induced in the wire sample Alloy seems to be the cheapest. Current flow generated magnetic field. If not specifically

Above, the process for increasing the 35 is indicated differently, the extent of the cold critical current density of hard superconductors by deformation was described between the process step of turning certain precipitation-bringing about homogenization and the process step of the additives and the class of alloy precipitation annealing treatment for all Discussions in which the method was kept essentially constant according to the samples used. Invention is applicable to advantage, outlined 40 _. . . _T

been. Example I.

The following exemplary embodiment shows the binary niobium

A special hard superconductor, which consists of an alloy with 25 percent by weight of zirconium with a binary base alloy based on niobium with a diameter of approx. tion. The description of the example, which analyzes the hydrogen and carbon, resulted in a content of 0.0056% O ₂ , 0.0017% N ₂ , by bringing about the necessary results, the separation phase according to the invention achieved 0.0005 ⁰ ZoH ₂ and 0.0080% carbon. The cast-stamped improvement in superconductivity measured was divided into 4 parts. The first part is revealed in detail on the basis of FIG. 1 50% added to the 0.0100% O _2; the second part to 3 of the drawing; of these shows 0.0250% O ₂ and the third part 0.0200% carbon

F i g. 1 is a graph showing the material by melting and casting the alloy parts in question with the effect of a certain addition of carbon O ₂ and carbon in an arc. material and oxygen to the critical current density j _L The oxygen was added as ZrO ₂ and the carbon as a function of a direction transverse to the electrical direction as ZrC. The fourth part received no current flow of an applied magnetic field in a niobium additive.

25% Zirconium Alloy Wire at 4.2 ° K in fms- Each of the alloy pieces went 51% cold

sigem helium, forged to 3.8 to 5.1 mm and then however-

F i g. Figure 2 is a graph in which the corn is analyzed. The results agreed with the critical current density of different alloy wires 60 addition match; the analysis of no addition entals Function of a holding alloy applied in the transverse direction agreed with the analysis before Magnetic field is applied and which corresponds to the dependent cold forging. The alloy parts were made the critical current density from the presence then to the formation of a precipitation phase of oxygen as the precipitation phase - annealed for about 15 minutes at 800 ° C and then Leading additive in the alloy illustrated 65 cold to a final diameter of about 0.406 mm 3 shows a graphical shape corresponding to FIGS. 1 and 2.

The effect of the oxygen and carbon density of the same niobium-zirconium base alloy added on the critical current density in this

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Type of manufactured wires is shown in FIG. 1 shown. density can lead. On the other hand, it was discovered that

From Fig. 1 it can be seen that the alloy samples show a reduction in dimension or diameter

with the addition of oxygen and carbon (the length of these wires, with a fixed dimension of

\ enA, B and C) compared to the wire cold deformation, leads to a strong increase in the critical

without such an addition (curve D) leads to a substantial current density, especially if the

lent increased critical current density. For example, chemical etching is used to reduce its size

is done with a magnet applied in the transverse direction.

field of 20 kilogauss the critical current density of the The mutual dependency and relationship between alloy wire sample without oxygen or carbon see this "dimensional effect" and the addition of cold material about 3-10 ⁴ AZCm ² ; on the other hand, deformation effects result from the following of that alloy wire sample (curve) which examples in connection with FIGS. 3 to 8 contain an addition of 0.0250% oxygen and in the drawing; of these shows

800 ° C of an annealing treatment to form a fig. 3 is a graph showing the

oxygen-containing precipitation phase subject to critical current density of a binary niobium-zirconium-

the critical current density is applied to the same base alloy with 25% zirconium,

applied magnetic field strength increased to 8 · 10 ⁴ A / cm ² . which after the to the curves / to M in the

That the addition of the specified amounts of oxygen was treated in the programs given in the figure,

or carbon not as such on its own without generating alloy wire samples that are based on

the presence of one containing the additive- an average diameter of about

the secondary elimination phase the increase ao 0.127 mm are processed, instead of a final diameter

the critical current density of the manufactured wires diameter of about 0.406 mm as with the alloy

the following example shows. samples according to Figs. 1 and 2,

_R. . . F i g. 4 a graphical representation in which the egg spie 11 critical current density as a function of the reciprocal. In this experiment, a binary niobium-zirconium diameter was applied to the wire sample and conium alloy with 25 percent by weight of zirconium, which shows the divergence of the measured critical nium in 4 parts divided and illustrated these into wires of current density of wires, which are processed in 3.96 to 0.406 mm diameter, and manufactured in exactly the same way, with the exception after the immediately after the designations, that in one case the final Abis , F, G and H in FIG. 2 specified program. 30 measurement reduction to a wire of less Like curves G and H in FIG. 2 show, have as 0.127 mm by chemical etching instead of those samples that have not been subjected to any mechanical precipitation, such as by cold annealing treatment, whether deformation was achieved with (curve H),

or without (curve G) addition of oxygen in the form of FIG. Figure 5 is a graph in which the zirconia has essentially the same value 35 critical current density versus the transverse critical current density. The effect of the applied magnetic field strength is plotted, whereby in the annealing treatment at 800 ° C with subsequent production of the wires, a constant off-cold deformation on the improvement of the critical measurement reduction by cold deformation on-current density of the alloy results from curve F, was applied,

which relates to an alloy sample showing the 40 F i g. 6 is a graph showing the same

original amount of oxygen, without particular importance of the coordinates as in FIG. 5 for

Oxygen addition, which contains, however, cold deformed illustrating the effect on the critical

and at the precipitation triggering temperature current density of alloy wire samples, which in

was annealed at 800 ° C. The alloy sample of the same size as the wire sample in FIG. 5

(Curve E), to which oxygen was subjected to cold working in an amount of 45 with the

0.0250% was added and the one combination difference that the reduction in wire dimensions

of cold working and precipitation annealing with a solution below about 0.399 mm by chemical etching

800 ° C was brought about by an increase instead of mechanically,

the critical current density almost by a factor of 3 F i g. 7 and 8 are those measured at two field strengths

versus the sample (curve F) at the measured 50 critical current density of the wire samples

applied magnetic field strength of 10 to 25 kilogauss against the logarithm of the ratio of

marked; with respect to the sample (curve ff), start and end cross-sectional area of the wire;

which 0.0250% O _{2 was} added, but these representations show the effect of a

no annealing treatment to bring about a cold deformation of the wire samples to achieve a

Was subjected to precipitation, the critical mechanical area reduction was greater than

Current density of the sample (curve E) averaged 99%.

increased by an average factor of more than 4. Example III

The influence of the dimensions _{A binary} Nk> b zirconium alloy with 25 Ge As mentioned above, the critical current 60 percent by weight zirconium was treated according to the methods described in the additional densities of superconducting alloys by cold working I and II even in the absence of a precipitation annealing with the difference that in the present case increase the treatment. However, the invention lies in the fact that wires up to a final diameter of 0.127 mm were processed, among other things, by the very unexpected finding. The manufacturing and processing basis, that in certain cases a mechanical process of these wires is in the explanations on processing hard superconductors over a critical / up to M in FIG. 3 reproduced. The curve / wire diameter also actually results in a down to M in FIG. 3 it can be seen that here, instead of an increase in the critical current, one would take obviously the same results as with the

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Curves in Figures 1 and 2 obtained; that is, always to distribute the oxygen evenly. The individual pieces were then subjected to a heat treatment at 800 ° C with a cross-sectional minin alloys, which were cold-forged as zirconium oxide and contain oxygen to form an oxygen-containing precipitation phase for 1 hour, the critical current density itself annealed for 5 long at 800 ° C. The annealed alloy increased in magnitude compared to the cases, was then added by means of cold drawing to a wire sample in which either no additional oxygen was processed with a final diameter of 0.254 mm (curves K and L) or where the same procedure was used an alloy oxygen was added, but no annealing blank was repeated to produce wire samples with a treatment to achieve a precipitation instead of the final diameter of 0.127 mm. On found (curve M). Particularly significant, however, is that two groups of wires were obtained in this way - the fact that the critical current density of all samples in which a constant 0.127 mm wire was noticeably higher, namely by one size diameter with different degrees of cold order than that of the 0.406 mm wires with deformation had been achieved. The critical same manufacturing and machining process is. For example, the 15 current densities of the final wire samples were obtained through processing step E at 4.2 ° K and one in the direction transverse to the direction and the associated curve E in FIG. 2 marked with the current flow induced in the wires applied wire sample almost the same production th magnetic field measured. The results are in the course like those through the processing course / and the graphic representations in FIG. 7 and 8 associated curve / in FIG. 3 marked wire ao in which the critical current density as a sample; Differences existed only with regard to the function of the logarithm of the ratio between the final diameter of the wire samples and the initial and final cross-section of the wires applied to the extent of the cold deformation. In detail is. It can be seen that reductions in cross-section experienced by the wire shown by the curve of over 99% actually lead to a reduction in the sample a cross-sectional reduction of 98.6%, instead of an increase during the increase shown by the curve / However, as it is obtained, a wire sample has a reduction in cross-section of only a lower 99.86% in the course of wire production. It can be seen that cross-section reductions are made in one. Transverse direction applied magnetic field of example

The critical current density of Example V is 20 kilogauss

0.406 mm wire is about 8 · IO ⁴ A / cm ² , while this experiment is intended to place the effect of the 0.127 mm wire under the same test and demonstrate that the conditions of a critical current density of a little measurement reduction points to the critical currents alone in excess of 1.5 x 10 ⁵ A / cm ² . This increase can exercise tight. This was achieved in such a way that the greater cold deformation is not attributed to the homogenized wire according to Example IV, as shown by the example below of various wire diameters from 7.75 to IV. Therefore, in addition to the 1.65 mm, by cold deformation, namely by means of cold deformation and the precipitation of an acidic increase in the diameter of 5.58 to 1.17 mm attributable to a 48% cross-sectional reduction on wire material-containing phase, the critical current density must obviously still be reduced Any 40 wires of various dimensions were then annealed for another factor to increase the critical one at 800 ° C for 1 hour and then to a current density such as that shown by the curves in FIG. 3 show 99.5% cold deformation contributing to a number of. Since the only obvious difference, subject to dimensions of 0.398 to 0.048 mm, as to the final diameter of the wire samples. The final samples thus obtained, this suggests that the dimension in any case is exactly the same manufacture and consistency as that observed Increased stress, however, had very different table current densities, as shown by the curves in FIG. 3 wire diameter. The results for showing in this way must contribute. treated wires are shown in FIG. Of the

. . second part of the experiment to expose and

Example IV _{5o to} N _acnwe j _s (j effect of _it Abmessungsverringe-

This example aims to reduce the effects of the tion alone by means of chemical etching prior to cold processing taken from the simultaneous effects. For this purpose, wires were isolated from the reduction in size and any 0.402 mm in diameter by the same procedure Differences in the effect of these parameters are produced as the wire in FIG. 5. This wire meter on the critical current density of superconducting 55 was then in its dimension, starting from the alloy samples can be detected. To 0.402 mm, further reduced, by means of chemidiesem Purpose, alloy wires were made with a shear etch by dipping in a solution constant diameter after a preparation of 75 percent by weight of nitric acid and 25 percent by weight and processing methods made that percent hydrofluoric acid, respectively was exactly the same for each of the individual samples, with 60 always only a few seconds at a time, so as not to the only exception is that one cold piece has to be removed more than a few hundredths of a millimeter, processing took place to the following extent: After immersion, the wire was rinsed,

An alloy blank of 8.9 mm diameter is cleaned and dried and then its critical with 0.0050% oxygen content was measured on wires with current density. The results are in the various diameters from 7.75 up to 1.65 mm 65 graphic representation of F i g. 6 reproduced, deformed; Pieces of the same length were then used in A comparison of the critical current density values of the 1500 ° C homogenized in order to avoid any contraction by 99.5% cold drawing with different Eliminate settlement fluctuations in them and diameters manufactured wires according to FIG. 5 in

In contrast to those in a non-mechanical way, such as by etching in their dimensions reduced wires according to FIG. 6 clearly shows that the chemical etching to dimensions below Wires reduced in diameter by about 0.177 mm have higher critical current densities than the corresponding ones Wires that have been reduced in size by cold processing.

The ratio of the effects of size reduction through mechanical processing drive versus size reduction using non-mechanical methods such as chemical etching, are made even clearer on the basis of the graph in FIG. 4, in which the critical current density versus the reciprocal diameter of the according to the present example manufactured wires is applied, once at 10 kilogauss and the other time for 25 kilogauss measured. The dashed curves in FIG. 4 give the characteristics of the chemically etched wires, ao the full line shows the characteristics of the reduced dimensions due to cold deformation Wires again. It should be noted that with the larger diameters, the cold forming Wires with a reduced diameter show the same values of the critical current density as the etched wires. When the wire diameter decreases above the value 100 of the reciprocal diameter (in centimeters) also shows the course of the critical current density for the etched wires increasing inclination, while the critical current density is constant for the cold-deformed wires Seems to strive for value. From this it is evident that chemical etching of the wires over a a certain wire diameter causes an increase in the critical current density by a factor, which is greater than the increase in the critical current density as shown by a combination of the Cold deformation and that increase in the critical current density, which results in the formation of a precipitation phase, which contains the additives according to the invention described above, is to be attributed. The particular exact value of the wire diameter at which the beneficial effect of the size reduction noticeably set in by non-mechanical means, such as chemical etching, depends on the composition of the Superconductor, the type of additive used to induce the precipitation phase, the previous one Manufacturing and processing history of the wire as well as the size of the wire used of the current flow in the wire in the transverse direction applied magnetic field variable.

The enhanced superconducting effects achieved by chemical etching of the small diameter wires can also be achieved by any other non-mechanical reduction in the wire dimensions beyond the point from which further mechanical processing does not increase the superconductivity provides more, achieve. Instead of chemical etching, for example Evaporation process to reduce the wire diameter while increasing its Superconductivity find application. The evaporation method is in terms of its applicability subject to greater restrictions than chemical etching, since in some cases the for Achieving a significant metal vapor pressure is part of the high temperatures required Eliminate the improvement in superconductivity achieved through previous cold deformation can.

With a view to achieving a maximum increase in superconductivity in a given hard superconductor in the present invention is the effect of precipitation phase and the effect of size reduction have been combined into a uniform process. To achieve a maximum Increase in the critical current density of a given hard superconductor alloy wire the manufacturing and processing method should be the formation of the described, the invention Additive containing precipitation phase, a cold deformation after the precipitation of the Include addition as well as further a reduction in size beyond the point of which, on the basis of cold deformation, no further influence on the superconductivity of the treated Alloy yields more.

Claims (8)

Patent claims: 1. Process for producing a hard superconducting alloy with increased critical Current density, characterized in that an alloy consisting of metals one or more of groups III, IV, V, VI, VII, VIII, IVa, Va and VIa of the periodic System consists in the liquid state as an additive oxygen, carbon, nitrogen or hydrogen mixed in, the alloy obtained in this way after deformation has taken place at a temperature below the melting point of the alloy to achieve an even distribution of the additive homogenized and the homogenized alloy after a possibly done Cold working to form a finely divided precipitation phase, which contains the additive mentioned contains, is annealed, whereupon the alloy is then reduced in size to a desired one lower wire thickness is cold formed. 2. The method according to claim 1, characterized in that the annealed and cold deformed Alloy is not mechanically reduced in diameter to such a value below which the critical current density of the alloy containing the precipitation phase can no longer be increased by cold forming or precipitation annealing. 3. The method according to claim 1 or 2, characterized in that the additive used is an oxide, carbide, hydride or nitride of the general formula MX , wherein M is a metal whose electronegativity is smaller than the electronegativity of the metal forming the main alloy constituent. 4. The method according to one or more of the preceding claims, characterized in, that a binary niobium-zirconium alloy is assumed. 5. The method according to claim 4, characterized in that a binary niobium-zirconium alloy 25 to 60 percent by weight of zirconium is assumed. 6. Method according to one or more of the Claims 2 to 5, characterized in that the non-mechanical reduction in diameter the precipitation-annealed and cold-worked alloy by means of chemical etching he follows. 7. The method according to one or more of claims 2 to 5, characterized in that the non-mechanical reduction of the diameter of the precipitation annealed and cold deformed alloy takes place by means of evaporation. 8. Modification of the method according to claim 1 for the production of a hard, superconducting Alloy with increased critical current density, characterized in that the alloy with the addition of an additive containing oxygen, carbon, nitrogen or hydrogen powder metallurgical processes and the resulting alloy then the deformation and subjected to heat treatments according to claim 1. For this purpose 2 sheets of drawings