Preparation method for multi-core MgB2/Fe/Cu superconducting wire

Abstract

The invention discloses a preparation method for a multi-core MgB2 / Fe / Cu superconducting wire. The preparation method comprises the following steps of: 1, preparing precursor powder; 2, filling the precursor powder into a pure iron tube, and placing the pure iron tube into a first oxygen-free copper tube to obtain a tubulated composite; 3, performing rotary forging and drawing treatment on the tubulated composite to obtain single-core wires; 4, placing a copper-niobium composite rod and six single-core wires into a second oxygen-free copper tube, performing secondary assembly to obtain a second composite rod, and performing rotary forging and drawing and grooving rolling treatment on the second composite rod to obtain a multi-core MgB2 / Fe / Cu wire; and 5, sealing the two ends of the wire, placing the sealed wire into a vacuum furnace, and performing vacuum sintering to obtain the multi-core MgB2 / Fe / Cu superconducting wire. The multi-core MgB2 / Fe / Cu superconducting wire has critical current density Jc reaching 1.8*10<4>A / cm<2> under 20 K and 1T, and a requirement for the practicability of the multi-core MgB2 / Fe / Cu superconducting wire is met.

Description

Technical field

[0001] The invention belongs to the technical field of superconducting material processing engineering, and specifically relates to a multi-core MgB 2 / Fe / Cu superconducting wire preparation method. Background technique

[0002] MgB 2 The material was synthesized as early as 1954, but its superconductivity was not discovered until 2001, due to its high critical temperature (T c =39K), and has the advantages of large coherence length, no weak grain boundary connection, etc., which has always been the research hotspot of various scientific research groups at home and abroad. After a large number of systematic studies, it has been found that element doping can improve MgB 2 Wire / strip is an effective means of high field current-carrying capacity, and TiC doping is also one of the effective dopants at present.

[0003] Currently preparing MgB 2 Superconducting wire strips mainly include continuous filling and molding technology, namely CTFF technology and traditional pow...

Examples

Embodiment 1

[0034] Step 1. Magnesium powder (particle size is -325 mesh, mass purity 99%), amorphous boron powder (mass purity above 99%) and TiC powder (mass purity 99%, particle size not greater than 1μm) according to Mg: The atomic ratio of B:TiC=1:1.96:0.04 is mixed, mixed evenly and pressed into a block, and then the block is placed in a mixed atmosphere of argon and hydrogen (the volume percentage of argon in the mixed atmosphere is 90%, The remainder is hydrogen) under the protection of heat treatment at 850℃ for 3 hours. After cooling, use an agate mortar to manually crush the block for 20 minutes. Put the crushed block into the agate tank, and follow the broken block and agate ball. Put the agate ball in the mass ratio of 1:10, ball mill at 500rpm for 3h, put the ball milled powder into a 200 mesh filter sieve for sieving, retain the sieved powder, remove the upper part of the sieve, and finally sieve Add a mixed powder of magnesium powder and boron powder with a mass of 8% of the...

Embodiment 2

[0041] Step 1. Magnesium powder (particle size is -325 mesh, mass purity 99%), amorphous boron powder (mass purity above 99%) and TiC powder (mass purity 99%, particle size not greater than 1μm) according to Mg: The atomic ratio of B:TiC=1:1.92:0.08 is mixed, mixed evenly and pressed into a block, and then the block is placed in a mixed atmosphere of argon and hydrogen (the volume percentage of argon in the mixed atmosphere is 95%, The remainder is hydrogen) under the protection of heat treatment at 950℃ for 1h. After cooling, use an agate mortar to manually crush the block for 30 minutes. Put the crushed block into an agate tank, according to the crushed block and agate ball Put the agate ball in the mass ratio of 1:15, ball mill at 400rpm for 1h, put the ball milled powder into a 325 mesh filter sieve for sieving, retain the sieved powder, remove the upper part of the sieve, and finally sieve Add a mixed powder of magnesium powder and boron powder with a mass of 15% by mass o...

Embodiment 3

[0048] Step 1. Magnesium powder (particle size is -325 mesh, mass purity 99%), amorphous boron powder (mass purity above 99%) and TiC powder (mass purity 99%, particle size not greater than 1μm) according to Mg: The atomic ratio of B:TiC=1:1.94:0.06 is mixed, mixed evenly and pressed into a block, and then the block is placed in a mixed atmosphere of argon and hydrogen (the volume percentage of argon in the mixed atmosphere is 92%, The remainder is hydrogen) under the protection of heat treatment at 900℃ for 1.5h. After cooling, use an agate mortar to manually crush the block for 25min. Put the crushed block into an agate tank, according to the crushed block and agate The mass ratio of the ball is 1:12 into the agate ball, ball milled at 450 rpm for 2 hours, the ball milled powder is put into a 300 mesh filter sieve for sieving, the sieved powder is retained, the upper part of the sieve is removed, and finally passed Add a mixed powder of magnesium powder and boron powder with ...

Technical field

[0001] The invention belongs to the technical field of superconducting material processing engineering, and specifically relates to a multi-core MgB 2 / Fe / Cu superconducting wire preparation method. Background technique

[0002] MgB 2 The material was synthesized as early as 1954, but its superconductivity was not discovered until 2001, due to its high critical temperature (T c =39K), and has the advantages of large coherence length, no weak grain boundary connection, etc., which has always been the research hotspot of various scientific research groups at home and abroad. After a large number of systematic studies, it has been found that element doping can improve MgB 2 Wire / strip is an effective means of high field current-carrying capacity, and TiC doping is also one of the effective dopants at present.

[0003] Currently preparing MgB 2 Superconducting wire strips mainly include continuous filling and molding technology, namely CTFF technology and traditional pow...

Examples

Embodiment 1

[0034] Step 1. Magnesium powder (particle size is -325 mesh, mass purity 99%), amorphous boron powder (mass purity above 99%) and TiC powder (mass purity 99%, particle size not greater than 1μm) according to Mg: The atomic ratio of B:TiC=1:1.96:0.04 is mixed, mixed evenly and pressed into a block, and then the block is placed in a mixed atmosphere of argon and hydrogen (the volume percentage of argon in the mixed atmosphere is 90%, The remainder is hydrogen) under the protection of heat treatment at 850℃ for 3 hours. After cooling, use an agate mortar to manually crush the block for 20 minutes. Put the crushed block into the agate tank, and follow the broken block and agate ball. Put the agate ball in the mass ratio of 1:10, ball mill at 500rpm for 3h, put the ball milled powder into a 200 mesh filter sieve for sieving, retain the sieved powder, remove the upper part of the sieve, and finally sieve Add a mixed powder of magnesium powder and boron powder with a mass of 8% of the...

Embodiment 2

[0041] Step 1. Magnesium powder (particle size is -325 mesh, mass purity 99%), amorphous boron powder (mass purity above 99%) and TiC powder (mass purity 99%, particle size not greater than 1μm) according to Mg: The atomic ratio of B:TiC=1:1.92:0.08 is mixed, mixed evenly and pressed into a block, and then the block is placed in a mixed atmosphere of argon and hydrogen (the volume percentage of argon in the mixed atmosphere is 95%, The remainder is hydrogen) under the protection of heat treatment at 950℃ for 1h. After cooling, use an agate mortar to manually crush the block for 30 minutes. Put the crushed block into an agate tank, according to the crushed block and agate ball Put the agate ball in the mass ratio of 1:15, ball mill at 400rpm for 1h, put the ball milled powder into a 325 mesh filter sieve for sieving, retain the sieved powder, remove the upper part of the sieve, and finally sieve Add a mixed powder of magnesium powder and boron powder with a mass of 15% by mass o...

Embodiment 3

[0048] Step 1. Magnesium powder (particle size is -325 mesh, mass purity 99%), amorphous boron powder (mass purity above 99%) and TiC powder (mass purity 99%, particle size not greater than 1μm) according to Mg: The atomic ratio of B:TiC=1:1.94:0.06 is mixed, mixed evenly and pressed into a block, and then the block is placed in a mixed atmosphere of argon and hydrogen (the volume percentage of argon in the mixed atmosphere is 92%, The remainder is hydrogen) under the protection of heat treatment at 900℃ for 1.5h. After cooling, use an agate mortar to manually crush the block for 25min. Put the crushed block into an agate tank, according to the crushed block and agate The mass ratio of the ball is 1:12 into the agate ball, ball milled at 450 rpm for 2 hours, the ball milled powder is put into a 300 mesh filter sieve for sieving, the sieved powder is retained, the upper part of the sieve is removed, and finally passed Add a mixed powder of magnesium powder and boron powder with ...

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