EN ISO 10618:1999

SLOVENSKI STANDARD
SIST EN ISO 10618:2000
01-december-2000
Ogljikova vlakna - Ugotavljanje nateznih lastnosti prej, impregniranih s smolo (ISO
10618:1999)
Carbon fibre - Determination of tensile properties of resin-impregnated yarns (ISO
10618:1999)
Kohlenstoffasern - Bestimmung des Zugverhaltens eines harzimprägnierten Garnes (ISO
10618:1999)
Fibres de carbone - Détermination des propriétés en traction sur fils imprégnés de résine
(ISO 10618:1999)
Ta slovenski standard je istoveten z: EN ISO 10618:1999
ICS:
59.100.20 Ogljikovi materiali Carbon materials
SIST EN ISO 10618:2000 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 10618:2000

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SIST EN ISO 10618:2000

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SIST EN ISO 10618:2000

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SIST EN ISO 10618:2000

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SIST EN ISO 10618:2000

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SIST EN ISO 10618:2000
INTERNATIONAL ISO
STANDARD 10618
First edition
1999-08-01
Carbon fibre — Determination of tensile
properties of resin-impregnated yarn
Fibres de carbone — Détermination des propriétés en traction sur fils
imprégnés de résine
A
Reference number
ISO 10618:1999(E)

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SIST EN ISO 10618:2000
ISO 10618:1999(E)
Contents
1 Scope .1
2 Normative references .1
3 Terms and definitions .1
4 Symbols.2
5 Principle.2
6 Apparatus and materials.2
7 Test specimens.3
8 Atmosphere for conditioning and testing .5
9 Procedure .5
10 Expression of results .5
11 Precision.8
12 Test report .8
Annex A (informative) Examples of heat-curable expoxy-resin systems.9
Annex B (informative) Examples of impregnating apparatus.10
Annex C (informative) Examples of tabs and tab-preparation apparatus .11
Annex D (informative) Examples of extensometers.13
©  ISO 1999
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic
or mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case postale 56 • CH-1211 Genève 20 • Switzerland
Internet iso@iso.ch
Printed in Switzerland
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SIST EN ISO 10618:2000
© ISO ISO 10618:1999(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO
member bodies). The work of preparing International Standards is normally carried out through ISO technical
committees. Each member body interested in a subject for which a technical committee has been established has
the right to be represented on that committee. International organizations, governmental and non-governmental, in
liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3.
Draft International Standards adopted by the technical committees are circulated to the member bodies for voting.
Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.
International Standard ISO 10618 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee
SC 13, Composites and reinforcement fibres.
Annexes A to D of this International Standard are for information only.
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SIST EN ISO 10618:2000

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SIST EN ISO 10618:2000
INTERNATIONAL STANDARD  © ISO ISO 10618:1999(E)
Carbon fibre — Determination of tensile properties of
resin-impregnated yarn
1 Scope
This International Standard specifies a method of test for the determination of the tensile strength, tensile modulus
of elasticity and strain at maximum load of a resin-impregnated yarn specimen. The method is applicable to yarns
(continuous and staple-fibre yarns) of carbon fibre for use as reinforcements in composite materials.
The tensile modulus of elasticity may be calculated by one of two methods, A and B. The result obtained will not
necessarily be the same in each case.
2 Normative references
The following normative documents contain provisions which, through reference in this text, constitute provisions of
this International Standard. For dated references, subsequent amendments to, or revisions of, any of these
publications do not apply. However, parties to agreements based on this International Standard are encouraged to
investigate the possibility of applying the most recent editions of the normative documents indicated below. For
undated references, the latest edition of the normative document referred to applies. Members of ISO and IEC
maintain registers of currently valid International Standards.
ISO 291:1997, Plastics — Standard atmospheres for conditioning and testing.
ISO 527-1:1993, Plastics — Determination of tensile properties — Part 1: General principles.
ISO 1886:1990, Reinforcement fibres — Sampling plans applicable to received batches.
ISO 1889:1997, Reinforcement yarns — Determination of linear density.
1)
ISO 10119:— , Carbon fibre — Determination of density.
ISO 10548:1994, Carbon fibre — Determination of size content.
3 Terms and definitions
For the purposes of this International Standard, the terms and definitions given in ISO 527-1 apply, with the
following addition:
3.1
cross-sectional area of a yarn
A
f
the linear density of a yarn divided by the density of the material in the yarn
NOTE It is expressed in square metres.

1) To be published. (Revision of ISO 10119:1992)
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SIST EN ISO 10618:2000
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ISO 10618:1999(E)
4 Symbols
The symbols used in this International Standard are as follows:
s tensile strength, in megapascals;
f
maximum tensile force, in newtons;
F
f
A cross-sectional area of yarn, in square metres;
f
r density of yarn, in kilograms per cubic metre;
f
T linear density of yarn, in tex;
tf
T linear density of impregnated yarn, in tex;
ti
E tensile modulus of elasticity, in gigapascals;
f
L extensometer gauge length, in millimetres;
0
L extensometer reading, in millimetres, at maximum load;
u
DL variation in the length, in millimetres, corresponding to the variation in the force, in newtons;
DF variation in the force, in newtons, corresponding to the variation in the length, in millimetres.
5 Principle
A sample of yarn is uniformly impregnated with resin, then cured to provide thin composite rod test specimens. The
specimens are loaded in tension at a constant speed by a suitable mechanical-testing machine until failure in order
to determine the load-extension curve.
The tensile strength, the tensile modulus of elasticity and the strain at maximum load are calculated from the force-
extension relationship.
The tensile modulus is determined by dividing the variation in the stress by the corresponding variation in the strain
between two points. For carbon-fibre yarns, the relation between stress and strain is not linear, hence a chord
modulus must be defined. In method A, the modulus is defined between two stress levels, whereas in method B it is
defined between two strain levels. For the purposes of this International Standard, method B is the reference
method. The linear density and the size content have to be determined independently.
NOTE The precision of the values obtained is the same for method A and for method B. Method A, or other methods, may
be used for purchase-specification or quality-control purposes by agreement between customer and supplier.
6 Apparatus and materials
6.1  Impregnating resin, compatible with the yarn and its size. The viscosity of the resin or resin solution shall be
such that sufficient resin pick-up is achieved to ensure uniform impregnation. The strain at failure of the cured resin
shall be at least twice that of the fibre, preferably three times. In this respect, heat-curable epoxy-resin systems with
a viscosity during impregnation of preferably less than 1000 mPa×s are suitable (see annex A for example), as is
any formulation capable of giving test specimens that fulfil the requirements of this International Standard. The resin
formulation, however, shall be specified in detail and shall be agreed upon between the fibre manufacturer and the
user.
6.2  Impregnation apparatus.
Test specimens can be prepared by any method which produces a uniformly impregnated, smooth specimen.
These methods include both single- and multiple-specimen preparation techniques. A multiple-specimen
impregnation apparatus may consist of the following:
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SIST EN ISO 10618:2000
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ISO 10618:1999(E)
  with yarn-tensioning devices.
6.2.1 Holder for the yarn-feed bobbin,
6.2.2  Impregnation bath, with temperature-control devices and impregnation rollers or yarn-tensioning bars.
6.2.3  Unit to remove excess resin from the impregnated yarn by passing it over rollers covered with fabric, paper
or felt and/or through a die.
6.2.4  Frame, to wind up the impregnated yarn, preferably made of wood or metal coated with rubber.
6.3  Curing oven, with temperature control. A fan circulation oven is preferred to ensure uniform curing of the
resin.
The temperature of the curing oven shall be controlled at ± 3 °C.
6.4  Tensile-testing machine, with a constant crosshead speed, equipped with force- and extension-recording
devices. The accuracy of the force indication shall be better than 1 % of the recorded value. The specimen-gripping
system shall ensure that the test specimen is aligned with the axis of the test machine.
 which automatically records the extension within
6.5 Extensometer linked to a continuous-recording device,
the gauge length of the extensometer as a function of the force acting on the test specimen. The extensometer shall
be sufficiently light to induce only negligible stresses in the test specimen.
The extensometer gauge length shall be at least 50 mm, but preferably 100 mm. The tolerance on the gauge length
shall be ±1 %.
The extensometer shall have a measurement tolerance of not more than 0,1 % over the required extension-
measurement range.
Examples of suitable extensometers are given in annex D. Other strain-measuring equipment, such as optical or
laser instruments, may be used, if suitable.
6.6  Balance, accurate to 0,1 mg, to weigh the test specimens in order to determine the linear density of the
impregnated yarn.
6.7  Graduated rule, at least 500 mm long and accurate to ± 1 mm, or other suitable measuring device.
7 Test specimens
7.1 Number of test specimens
Prepare sufficient test specimens to enable five valid determinations to be made. If any of the specimens fails within
the grips or at the tabs, or because of damage caused by the extensometer, discard the result and carry out a
repeat on a fresh test specimen.
7.2 Length of test specimens
For test specimens with tabs, the length of the test specimen between the tabs shall be either 150 mm ± 5 mm or
200 mm ± 5 mm. For test specimens without tabs, the total length of the test specimen shall be 250 mm ± 5 mm or
300 mm ± 5 mm (at least the extensometer gauge length plus twice the grip length).
In cases of dispute, for test specimens with tabs the length between the tabs shall be 150 mm ± 5 mm and for test
specimens without tabs the length of the test specimen shall be 250 mm ± 5 mm.
7.3 Preparation of test specimens
The procedure using the impregnation apparatus described in 6.2 is as follows:
Place the yarn bobbin on the holder.
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SIST EN ISO 10618:2000
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Pour the impregnating-resin mixture into the resin bath and adjust the temperature and viscosity to the desired
values.
Draw the yarn through the resin bath and through the system designed to remove
...