IEC TR 61788-20:2014

IEC TR 61788-20 ®
Edition 1.0 2014-07
TECHNICAL
REPORT
Superconductivity –
Part 20: Superconducting wires – Categories of practical superconducting
wires – General characteristics and guidance

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IEC TR 61788-20 ®
Edition 1.0 2014-07
TECHNICAL
REPORT
Superconductivity –
Part 20: Superconducting wires – Categories of practical superconducting

wires – General characteristics and guidance

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
R
ICS 29.050 ISBN 978-2-8322-1779-5

– 2 – IEC TR 61788-20:2014 © IEC 2014
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Categories of practical SC wires . 7
5 Technical sheet assisting in the specification and the use of practical SC wires. 8
6 Class of practical SC wires . 8
7 Product parameters . 8
8 Joints . 8
9 Appearance . 8
10 Quality assurance . 8
11 Test methods . 8
12 Inspection . 9
13 Shipping label . 9
Annex A (informative) Structural characteristics of practical SC wires . 10
A.1 General . 10
A.2 Overview of SC materials . 10
A.3 Overview of functional components . 10
A.3.1 Matrix materials . 10
A.3.2 Stabilizer . 11
A.3.3 Reinforcing component . 11
A.3.4 Insulation . 11
Annex B (informative) Classes of practical SC wires . 13
B.1 Nb-Ti group . 13
B.2 Nb Sn group . 13
B.3 MgB . 14
B.4 BSCCO group . 15
B.5 REBCO group . 15
Annex C (informative) Technical information assisting in the specification and use of
practical SC wires . 17
C.1 General . 17
C.2 Product parameters . 17
C.3 Appearance . 17
C.4 Quality assurance . 17
C.5 Test methods . 17
C.6 Technical record . 18
Bibliography . 19

Table B.1 – Constituents composing the Nb-Ti group SC wires . 13
Table B.2 – Constituents composing the Nb Sn group SC wires . 14
Table B.3 – Constituents composing the MgB SC wires . 14
Table B.4 – Constituents composing the BSCCO SC wires . 15
Table B.5 – Constituents composing REBCO SC wires . 16

– 4 – IEC TR 61788-20:2014 © IEC 2014
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SUPERCONDUCTIVITY –
Part 20: Superconducting wires –
Categories of practical superconducting wires –
General characteristics and guidance

FOREWORD
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The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a technical report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC 61788-20, which is a technical report, has been prepared by IEC technical committee
90: Superconductivity.
The text of this technical report is based on the following documents:
Enquiry draft Report on voting
90/335/DTR 90/344/RVC
Full information on the voting for the approval of this technical report can be found in the
report on voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 61788-20 series, published under the general title
Superconductivity, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

– 6 – IEC TR 61788-20:2014 © IEC 2014
INTRODUCTION
Superconducting (SC) wires are a central and often enabling technology of many important
industrial products. Consensus-based standards for SC wires greatly facilitate the creation of
procurement specifications, design and engineering of components, certification of quality,
description of operating devices, and generalization of use in industrial technologies.
The present technical report (TR IEC61788-20) provides a description of the general features
of practical SC wires. The practical low temperature superconducting (LTS) wires have been
used extensively in a variety of applications since the late 1960s. These applications include
magnetic resonance imaging magnets, research an
...