DE2011581C - Process for the production of a niobium titanium superconductor - Google Patents

Description

nium, tantai, hafnium, carbon, oxygen and nitrogen, individually or in groups, where the heat treatment of the starting alloy preceding the rapid cooling process at a temperature between 800 and 1000 ° C and the second stage of the final aging over 0.5 to 6 hours are preferably undertaken, results from the following examples.

Example i

... ^E5ne ° ^Ni b-65 <Vo titanium alloy was initially heated for 1 hour at 950 ⁰ C, then rapidly cooled and then under a Flächenreduzie tion of 99.9% eezoeen to a wire. This

LMiuii wuiuc uann heated in vacuum to 300 ° C for 127 hours and finally to 375 ° C for 1 hour. The conductor obtained gave a critical current density of 2.5 x 10 6 "Amp./cm ² at a temperature of 4.2 ° K in an external magnetic field of 30 kG, and its tensile strength was 175 kg / mm- ¹ . The same starting alloy became for comparison, after cold forming, heated for 1 hour to 400 ° C. The conductor showed a critical current density of 1.8 · 105 Amp./cm ² in an external magnetic field of 30 kG and had a tensile strength of 160 kg / mm ² .

Example 2

A niobium-35% titanium alloy was first heated to 950 ° C. for 1 hour and then rapidly cooled. The alloy was then coated with copper and then cold-drawn to form a wire with a niobium-titanium core with a diameter of 0.25 mm and an outside diameter of 0.33 mm with a reduction in area of 99.9%. This wire was then heated in vacuo to 250 ° C. for 250 hours and finally to 400 ° C. for 1 hour. The resulting conductor showed a critical current density of 2.15-10 ⁵ amps / cm ² in an external magnetic field of 30 kG and had a tensile strength of 120 kg / mm ² .

For comparison, the same alloy was heated to 425 ° C. for 1 hour after cold working. The resulting conductor showed a critical current density of 1.65 · 10 'Amp./cm ² in an external magnetic field of 30 kG and had a tensile strength of 110 kg / mm ² .

Example 3

A niobium 50% titanium alloy with an additive of 1 percent by weight tantalum, 0.28 percent by weight Oxygen and 0.12 weight percent nitrogen heated over 1 hour to 1000 ° C and then quickly cooled The alloy then became a wire with a reduction in area of 99.5% pulled, which then in vacuum initially over Was heated to 250 ° C and finally over ι hour to 400 ° C for 120 hours. The resulting conductor showed a critical current density of 2.3 · ^{10 s AmpVcm 2} in an external magnetic field of 3OkG.

uicsciuc alloy was used for casting after

the cold forming heated to 425 ° C over 1 hour. The resulting conductor exhibited a critical current density of 1.75 · lü · " ¹ amp./cm ² .

Example 4

A niobium 30%> titanium alloy with an addition of 1.5 percent by weight of zirconium and 2.5 percent by weight Tantalum and less than 350 ppm oxygen were heated to 950 ° C. over 1 hour

a ₅ and then rapidly cooled. The alloy was then drawn under an area reduction of 99.8% to a wire, which was then heated in vacuum initially for 200 hours at 375 ° C and finally for 1.5 hours at 480 ⁰ C. The resulting conductor exhibited a critical current density of 1.2 · 10 ⁵ AmpVcm- in an external magnetic field of 75 kG.

The same alloy showed a critical current density of 0.5 · 10 ⁵ Amp./cm- with only one-stage aging following cold deformation.

Example 5

A niobium 30% titanium alloy with an addition of 0.2 percent by weight carbon and 1.1 percent by weight oxygen was heated to 950 ° C. for 1 hour and then cooled with smoke. The alloy was then cold-drawn with a reduction in area of 99.5% to form a wire, which was finally heated first to 300 ° C. over 130 hours and then to 430 ° C. over 5 hours. The resulting conductor exhibited a critical current density of 1.5 · 10 ⁵ AmpVcm ² in an external magnetic field of 75 kG.

Claims (1)

I 2 a 99% cold-deformed conductor according to a patent claim: heat treatment over 0.1 to 5 hours, a critical field strength of at least 50 kG and a critical current density of at least about 1. Process for the production of a niobium 5 0.4 · 10 * Ampfern * in an external magnetic field of iitan-inipconductors with 30 to 70 weight percent 20 kG shows when the treatment temperature with niobium, which after its on a heat treatment approx ⁰ C is selected, and on the other hand it is aged in two stages of forming the starting alloy following cold working at a treatment temperature of about 400 ° C, the first having a critical field strength of at least 70 kG and a critical level compared to the second stage in an io Current density of at least approximately a lower temperature range and over a 0.7 · 10 * AmpVcm * in an external magnetic field of a longer period of time is carried out, since it has about 20 kG. Furthermore, this is characterized by the fact that the printout indicates that the value for the transition alloy before its cold deformation is msr-h tritic-h »c» ^ _m , i; ^ ht _o ^ „rii ^ r τ <»;» »R _a> , r ....... aDgeicufnt and then the first stage of the final 15 0.9 · 105 Amp./cm- 'or 1.0 · 10 ·' Amp. / cm ² in a benclen aging at a temperature between external magnetic fields of about 20 kG leaves, 150 and 400 C for 5 to 250 hours and if such a heat treatment at 300 or second stage at a temperature between 350 400 "C for 2.5 hours after cold forming and 550 C for 0.3 to 10 hours - aging of the conductor at room temperature men will be _{prefixed 30} ( _{I () to 5 ()} <> q _over 5 months, I. The method according to claim 1, characterized in that the indication is given that a short time indicates that the heat treatment of the conductors preceding the rapid cooling spaces for this aging hardly affect the superconductivity of the process and that an over multiple starting alloy at a temperature between - More months of aging the best properties 800 and 1000 ° C is made. 25 shafts for the head can be achieved. J. method according to claims 1 and 2, from the German Auslegesehrift 1 188 824 is characterized in that the second stage continues ^vo to a process for the preparation of suprader final aging for 0.5 to 6 STUN conductive wires and tapes made of titanium-niobium A ';.. s ^{e "o, mmen Wl} l ^d - alloys known where the raw material from 4 method according to one of claims 1 to 30 alloys with 20 to 45 percent by weight niobium, up to 3, characterized in that the supra-remainder of titanium, initially from the temperature range conductor, is cooled so quickly before the final aging with the /? Phase that this is copper-plated. _{hold and next to it only} martensitic, over- w λ ίΤΤ ι - ^{one of the claims 1 saturated "solid solution} , but no equilibrium ^, characterized in that the starting 35" solid solution occurs and is then cold-formed into wires and alloy in addition to 30 to 70 percent by weight of niobium strips, which then only lian or in addition to titanium up to 4% by weight heat treatment over a specified percent molybdenum vanadium, zirconium, tan period of 10 to 25 hours at temperatures al, hafnium, carbon, oxygen and stick between 250 and 650 ⁰ C and preferably contains an intermediate, individually or in groups. 40 see 350 and 600 ⁰ C are subjected, with Annealing temperature and duration are coordinated in such a way that the ■ Targeted lamellar structure of the structure preserved remains, whereupon there may be a slight nu Rrfir, ^ u ♦ · «* · ,, _ ,. ⁴⁵ closing deformation follows. This procedure The invention relates to a method of manufacturing that fundamentally differs from the invention of a niobium-titanium silicon conductor with 30 to 70Ge methods and from the method according to vvichtsprozent niobium, which according to his on one of the German Auslegesehrift 1289 997 in that Heat treatment of the starting alloy following the aging following the cold deformation only Ka! Deformation [is aged in two stages, with the 50 being carried out in one stage. nSdriS2n ^ J ^eitf f ^IC i ^to . ^r _u ^second , ^e " ^{stage in} one The invention is based on the object that lower temperature range and carried out over a longer process of the type mentioned in the Rich-Äer w.rd. _{to improve> that} niobium-titanium superconductor with a VerfS, ^German ^ ⁿ A ^u slegesehrift 1289997 is higher values for the critical current density in procedures for increasing the critical field 55 can be set SnetSemvnn ^ m ¹¹⁶ ! ¹ , ^{current density in s} , strong »™ * ^{According to the} invention, the object is thereby Kk JerfnlT superconductors in order to at least release the fact that the starting alloy is In mi η W, r £ Τ ^"Nl0b Ti ^at - ^Le ß ^{c ycle} - rapidly cooled guild and that the first stage of Sm'iß welihim i G ^ htsprozent Titan known final aging at a temperature be- for whom! th 0 % Γ ⁿ " ^{Ch d} Z- ^cold r ^c [ ^formun ß ^6o see 150 and 400 ⁰ C over 5 to 250 hours and hoi 5, '? "α ⁶ ". ^{For a heat} treatment, the second stage at a temperature between 350 SnteioZ Ξ? ^η ηΓ w ^ICh Tu ^lO u ^{up to 600} ° ^{C and 55} °° ^{C for 3 to} 10 hours. This heat treatment which will range k ^S to ^U n ^d krnn ^a l ^a Z ^{ßCbeiii:, r 0} ^ f ₁ ^limit The progressiveness of this invention Hp. Ι Ρίιϊ "'κ!" Aging by aging 65 measure, which is preferably applied to the starting alloy oe amren m "^ ^^! n ^ MSV!" ^ ^ ^ß "is ^realized , which in addition to 30 to 70 weight It is now! T precede of 10 to 5O ⁰ C. percent niobium only titanium or up to next to titanium b.s is now shown in this publication that 4 percent by weight of molybdenum, vanadium, zirconia