EN 61788-18:2013

Superconductivity - Part 18: Mechanical properties measurement - Room temperature tensile test of Ag- and/or Ag alloy-sheathed Bi-2223 and Bi-2212 composite superconductors

IEC 61788-18:2013 specifies a test method detailing the tensile test procedures to be carried out on Ag/Bi-2223 and Ag/Bi-2212 superconductive composite wires at room temperature. This test is used to measure the modulus of elasticity and to determine the 0,2 % proof strength. When the 0,2 % proof strength could not be determined due to earlier failure, the stress level at apparent strains of 0,05 %, 0,1 %, 0,15 %, 0,2 %, 0,25 % with increment of 0,05 % is measured. The values for elastic limit, fracture strength, percentage elongation after fracture and the fitted type of 0,2 % proof strength serve only as a reference. The sample covered by this test procedure should have a round or rectangular cross-section with an area of 0,3 mm2 to 2,0 mm2 (corresponding to the tape-shaped wires with width of 2,0 mm to 5,0 mm and thickness of 0,16 mm to 0,4 mm). Key words: superconductivity, mechanical properties measurement

Supraleitfähigkeit - Teil 18: Messung der mechanischen Eigenschaften - Zugversuch von Ag und/oder Ag-Legierung ummantelten Bi-2223 und Bi-2212 Verbundsupraleitern bei Raumtemperatur

Supraconductivité - Partie 18: Mesure des propriétés mécaniques - Essai de traction à température ambiante des supraconducteurs composites Bi-2223 et Bi-2212 avec gaine Ag et/ou en alliage d'Ag

La CEI 61788-18:2013 spécifie une méthode d'essai détaillant les modes opératoires d'essai de traction à exécuter sur des fils composites supraconducteurs d'Ag/Bi-2223 et d'Ag/Bi-2212 à température ambiante. Cet essai est utilisé pour mesurer le module d'élasticité et pour déterminer la charge d'épreuve à 0,2 %. Lorsqu'on ne peut pas déterminer la charge d'épreuve à 0,2 % en raison d'une défaillance antérieure, on mesure le niveau de contrainte pour des déformations apparentes de 0,05 %, 0,1 %, 0,15 %, 0,2 %, 0,25 % avec un incrément de 0,05 %. Les valeurs de la limite élastique, de la résistance à la rupture, du pourcentage d'allongement après fracture et du type ajusté de charge d'épreuve à 0,2 % ne servent que de référence. Il convient que l'échantillon couvert par ce mode opératoire d'essai ait une section circulaire ou rectangulaire d'une surface de 0,3 mm2 à 2,0 mm2 (correspondant aux fils en forme de bande d'une largeur de 2,0 mm à 5,0 mm et d'une épaisseur de 0,16 mm à 0,4 mm). Mots clé: supraconductivité, propriétés mécaniques

Superprevodnost - 18. del: Merjenje mehanskih lastnosti - Natezni preskus Ag- in/ali z Ag zlitino oplaščenih Bi-2223 in Bi-2212 kompozitnih superprevodnikov pri sobni temperaturi (IEC 61788-18:2013)

General Information

• Status: Published
• Publication Date: 12-Dec-2013
• Withdrawal Date: 16-Oct-2016
• ICS: 29.050 - Superconductivity and conducting materials
• Technical Committee: CLC/SR 90 - Superconductivity
• Drafting Committee: IEC/TC 90 - IEC_TC_90
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 13-Dec-2013
• Completion Date: 13-Dec-2013
• Ref Project: SIST EN 61788-18:2014 - Superconductivity - Part 18: Mechanical properties measurement - Room temperature tensile test of Ag- and/or Ag alloy-sheathed Bi-2223 and Bi-2212 composite superconductors

Standards Content (Sample)

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Superconductivity - Part 18: Mechanical properties measurement - Room temperature
tensile test of Ag- and/or Ag alloy-sheathed Bi-2223 and Bi-2212 composite
superconductors
Supraconductivité - Partie 18: Mesure des propriétés mécaniques - Essai de traction à
température ambiante des supraconducteurs composites Bi-2223 et Bi-2212 avec gaine
Ag et/ou en alliage d'Ag
Ta slovenski standard je istoveten z: EN 61788-18:2013
ICS:
29.050 Superprevodnost in prevodni Superconductivity and
materiali conducting materials
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 61788-18
NORME EUROPÉENNE
December 2013
EUROPÄISCHE NORM
ICS 29.050
English version
Superconductivity -
Part 18: Mechanical properties measurement -
Room temperature tensile test of Ag- and/or Ag alloy-sheathed Bi-2223
and Bi-2212 composite superconductors
(IEC 61788-18:2013)
Supraconductivité -  Supraleitfähigkeit -
Partie 18: Mesure des propriétés mécaniques - Teil 18: Messung der mechanischen
Essai de traction à température ambiante des Eigenschaften -
supraconducteurs composites Bi-2223 et Zugversuch von Ag und/oder Ag-Legierung
Bi-2212 avec gaine Ag et/ou en alliage d'Ag ummantelten Bi-2223 und Bi-2212
(CEI 61788-18:2013) Verbundsupraleitern bei Raumtemperatur
(IEC 61788-18:2013)
This European Standard was approved by CENELEC on 2013-10-17. CENELEC members are bound to comply
with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard
the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the CEN-CENELEC Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and notified
to the CEN-CENELEC Management Centre has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus,
the Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany,
Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

CEN-CENELEC Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2013 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 61788-18:2013 E
Foreword
The text of document 90/326/FDIS, future edition 1 of IEC 61788-18, prepared by IEC/TC 90
"Superconductivity" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
– latest date by which the document has to be implemented at (dop) 2014-07-17
national level by publication of an identical national
standard or by endorsement
– latest date by which the national standards conflicting with (dow) 2016-10-17
the document have to be withdrawn

Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
Endorsement notice
The text of the International Standard IEC 61788-18:2013 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 61788-6 NOTE Harmonized as EN 61788-6.
ISO 3611:2010 NOTE Harmonized as EN ISO 3611:2010 (not modified).

- 3 - EN 61788-18:2013
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.
NOTE  When an international publication has been modified by common modifications, indicated by (mod), the
relevant EN/HD applies.
Publication Year Title EN/HD Year
IEC 60050 series International Electrotechnical Vocabulary - -
ISO 376 - Metallic materials - Calibration of force- EN ISO 376 -
proving instruments used for the
verification of uniaxial testing machines
ISO 6892-1 - Metallic materials - Tensile testing EN ISO 6892-1 -
Part 1: Method of test at room temperature
ISO 7500-1 - Metallic materials - Verification of static EN ISO 7500-1 -
uniaxial testing machines
Part 1: Tension/compression testing
machines - Verification and calibration of
the force-measuring system
ISO 9513 - Metallic materials - Calibration of EN ISO 9513 -
extensometer systems used in uniaxial
testing
IEC 61788-18 ®
Edition 1.0 2013-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Superconductivity –
Part 18: Mechanical properties measurement – Room temperature tensile test of

Ag- and/or Ag alloy-sheathed Bi-2223 and Bi-2212 composite superconductors

Supraconductivité –
Partie 18: Mesure des propriétés mécaniques – Essai de traction à température

ambiante des supraconducteurs composites Bi-2223 et Bi-2212 avec gaine Ag

et/ou en alliage d'Ag
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX W
ICS 29.050 ISBN 978-2-8322-1051-2

– 2 – 61788-18 © IEC:2013
CONTENTS
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Principle . 9
5 Apparatus . 9
5.1 General . 9
5.2 Testing machine . 9
5.3 Extensometer . 9
6 Specimen preparation . 9
6.1 General . 9
6.2 Length of specimen . 10
6.3 Removing insulation . 10
6.4 Determination of cross-sectional area (S ) . 10
7 Testing conditions . 10
7.1 Specimen gripping . 10
7.2 Setting of extensometer . 10
7.3 Testing speed . 10
7.4 Test . 10
8 Calculation of results . 12
8.1 Modulus of elasticity (E) . 12
8.2 0,2 % proof strength (R ) . 13
p 0,2
8.3 Tensile stress at specified strains (R ) . 13
A
8.4 Fracture strength (R ) . 14
f
9 Uncertainty of measurement . 14
10 Test report . 14
10.1 Specimen . 14
10.2 Results . 15
10.3 Test conditions . 15
Annex A (informative) Additional information relating to Clauses 1 to 14 . 16
Annex B (informative) Uncertainty considerations . 26
Annex C (informative) Specific examples related to evaluation of uncertainties for
Ag/Bi-2223 and Ag/Bi-2212 wires . 30

Figure 1 – Typical stress-strain curve and definition of modulus of elasticity and 0,2 %
proof strengths of an externally laminated Ag/Bi-2223 wire by brass foil . 11
Figure 2 – Typical stress-strain curve of an Ag/Bi-2223 wire where the 0,2 % proof
strengths could not be determined and definition of tensile stresses at specified strains . 12
Figure A.1 – Low mass Siam twin type extensometer with a gauge length of ~ 12,3 mm
(total mass ~ 0,5 g) . 16
Figure A.2 – Low mass double extensometer with a gauge length of ~ 25,6 mm (total
mass ~ 3 g) . 17
Figure A.3 – An example of the extensometer provided with balance weight and vertical
specimen axis . 18
Figure A.4 – Original raw data of an Ag/Bi-2223 wire measurement in form of load and
displacement graph . 19

61788-18 © IEC:2013 – 3 –
Figure A.5 – Typical stress versus strain of an Ag/Bi-2223 wire up to the elastic limit
corresponding to the transition region from elastic to plastic deformation (point G) . 20
Figure C.1 – Measured stress versus strain curve for Bi-2223 wire . 31

Table A.1 – Results of relative standard uncertainty values achieved on different
Ag/Bi-2223 wires during the international round robin tests . 23
Table A.2 – Selected data for F test for E of Sample E bare wire . 24
Table A.3 – Results of F-test for the variations of E of four kinds of Bi-2223 wires . 24
Table B.1 – Output signals from two nominally identical extensometers . 27
Table B.2 – Mean values of two output signals . 27
Table B.3 – Experimental standard deviations of two output signals . 27
Table B.4 – Standard uncertainties of two output signals . 27
Table B.5 – Coefficient of variations of two output signals . 28
Table C.1. – Load cell specifications according to manufacturer’s data sheet. 32
Table C.2 – Uncertainties from various factors for stress measurement . 33
Table C.3 – Uncertainties with respect to measurement of strain measurement . 35
Table C.4 – Summary of evaluated uncertainties caused by various factors . 35
Table C.5 – Results of uncertainty evaluation for the modulus of elasticity (E = 86,1
GPa) as a function of initial cross head rate . 36
Table C.6 – Uncertainties from various factors for stress measurement . 37
Table C.7 – Results of uncertainty evaluation for the stress (R = 42,5 MPa) as a function
of initial strain rate .
...