oSIST prEN ISO 527-4:2023

Plastics - Determination of tensile properties - Part 4: Test conditions for isotropic and orthotropic fibre-reinforced plastic composites (ISO/FDIS 527-4:2022)

This document specifies the test conditions for the determination of the tensile properties of isotropic and orthotropic fibre-reinforced plastic composites, based upon the general principles given in ISO 527-1.
NOTE 1   Unidirectional reinforced materials are covered by ISO 527-5.
The methods are used to investigate the tensile behaviour of the test specimens and for determining the tensile strength, tensile modulus, Poisson's ratios and other aspects of the tensile stress-strain relationship under the defined conditions.
The test method is suitable for use with the following materials:
—    fibre-reinforced thermosetting and thermoplastic composites incorporating non-unidirectional reinforcements such as mats, woven fabrics, woven rovings, chopped strands, combinations of such reinforcements, hybrids, rovings, short or milled fibres or preimpregnated materials (prepregs);
NOTE 2   Injection moulded specimens are covered by ISO 527-2.
—    combinations of the above with unidirectional reinforcements and multidirectional reinforced materials constructed from unidirectional layers, provided such laminates are symmetrical;
NOTE 3   Materials with completely or mainly unidirectional reinforcements are covered by ISO 527-5.
—    finished products made from materials mentioned above.
The reinforcement fibres covered include glass fibres, carbon fibres, aramid fibres and other similar fibres.

Kunststoffe - Bestimmung der Zugeigenschaften - Teil 4: Prüfbedingungen für isotrop und anisotrop faserverstärkte Kunststoffverbundwerkstoffe (ISO/FDIS 527-4:2022)

Dieses Dokument legt die Prüfbedingungen für die Bestimmung der Zugeigenschaften von isotropen und anisotropen faserverstärkten Kunststoffverbundwerkstoffen auf der Basis der allgemeinen Grundsätze aus ISO 527 1 fest.
ANMERKUNG 1   Unidirektional verstärkte Werkstoffe werden in ISO 527 5 behandelt.
Die Verfahren werden verwendet, um das Zugverformungsverhalten von Probekörpern zu untersuchen und die Zugfestigkeit, den Zugmodul, die Poissonzahlen und andere Gesichtspunkte der Zugspannungs-Dehnungs-Beziehung unter festgelegten Bedingungen zu ermitteln.
Das Prüfverfahren ist für Anwendung bei den folgenden Werkstoffen geeignet:
   thermoplastische und duroplastische (wärmehärtbare) Verbundwerkstoffe mit nicht-unidirektionalen Verstärkungen, wie Matten, Gewebe, Rovinggewebe, geschnittene Fasern, Kombinationen derartiger Verstärkungen, Mischverstärkungen, Rovings, Kurzfasern oder gemahlene Fasern oder vorimprägnierte Werkstoffe (Prepregs);
ANMERKUNG 2   Spritzgegossene Probekörper werden in ISO 527 2 behandelt.
   Kombinationen der vorstehend genannten Werkstoffe mit unidirektionalen Verstärkungen und multidirektionale verstärkte Werkstoffe, die aus unidirektionalen Schichten aufgebaut sind, vorausgesetzt, derartige Schichtwerkstoffe (Laminate) sind symmetrisch;
ANMERKUNG 3   Werkstoffe mit ausschließlich oder überwiegend unidirektionalen Verstärkungen werden in ISO 527 5 behandelt.
   Fertigerzeugnisse aus den vorstehend genannten Materialien.
Die berücksichtigten Verstärkungen schließen Glasfasern, Kohlenstofffasern, Aramidfasern und andere ähnliche Fasern ein.

Plastiques - Détermination des propriétés en traction - Partie 4: Conditions d'essai pour les composites plastiques renforcés de fibres isotropes et orthotropes (ISO/FDIS 527-4:2022)

Le présent document spécifie les conditions d’essai pour la détermination des propriétés en traction des composites plastiques renforcés de fibres isotropes et orthotropes, basées sur les principes généraux établis dans l’ISO 527‑1.
NOTE 1      Les matériaux renforcés unidirectionnels sont traités dans l’ISO 527‑5.
Les méthodes sont utilisées pour étudier le comportement en traction des éprouvettes et pour déterminer la résistance en traction, le module d’élasticité en traction, les coefficients de Poisson et d’autres aspects de la relation contrainte/déformation en traction dans les conditions définies.
La méthode d’essai convient aux matériaux suivants:
—    les composites thermodurcissables et thermoplastiques renforcés de fibres, contenant des renforts non unidirectionnels comme les mats, les tissus (fils de base ou stratifils), les fils de base coupés, les combinaisons de tels renforts, les hybrides, les stratifils, les fibres courtes et broyées ou les matériaux préimprégnés (prepregs);
NOTE 2      Les éprouvettes moulées par injection sont couvertes par l’ISO 527-2.
—    les combinaisons de matériaux ci-dessus avec un renfort unidirectionnel, et les matériaux renforcés multidirectionnels réalisés avec des couches unidirectionnelles, sous réserve que ces stratifiés soient symétriques;
NOTE 3      Les matériaux à renfort parfaitement ou principalement unidirectionnel sont couverts par l’ISO 527‑5.
—    les produits finis fabriqués avec les matériaux mentionnés ci-dessus.
Les fibres de renforcement concernées comprennent les fibres de verre, les fibres de carbone, les fibres d’aramide et autres fibres similaires.

Polimerni materiali - Določanje nateznih lastnosti - 4. del: Preskusni pogoji za izotropne in ortotropne z vlakni ojačene polimerne kompozite (ISO/FDIS 527-4:2022)

General Information

• Status: Not Published
• Public Enquiry End Date: 22-Feb-2023
• ICS: 83.120 - Reinforced plastics
• Technical Committee: IPMA - Polimer materials and products
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 07-Dec-2022
• Due Date: 26-Apr-2023
• Ref Project: prEN ISO 527-4 - Plastics - Determination of tensile properties - Part 4: Test conditions for isotropic and orthotropic fibre-reinforced plastic composites (ISO/FDIS 527-4:2022)

Relations

• Revised: SIST EN ISO 527-4:2022 - Plastics - Determination of tensile properties - Part 4: Test conditions for isotropic and orthotropic fibre-reinforced plastic composites (ISO 527-4:2021, Corrected version 2022-02)
• Effective Date: 02-Nov-2022
• Revised: SIST EN ISO 527-4:2022 - Plastics - Determination of tensile properties - Part 4: Test conditions for isotropic and orthotropic fibre-reinforced plastic composites (ISO 527-4:2021, Corrected version 2022-02)
• Effective Date: 18-Jan-2023
• Revised: SIST EN ISO 527-4:2022 - Plastics - Determination of tensile properties - Part 4: Test conditions for isotropic and orthotropic fibre-reinforced plastic composites (ISO 527-4:2021, Corrected version 2022-02)
• Effective Date: 19-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN ISO 527-4:2023
01-februar-2023
Polimerni materiali - Določanje nateznih lastnosti - 4. del: Preskusni pogoji za
izotropne in ortotropne z vlakni ojačene polimerne kompozite (ISO/FDIS 527-
4:2022)

Plastics - Determination of tensile properties - Part 4: Test conditions for isotropic and

orthotropic fibre-reinforced plastic composites (ISO/FDIS 527-4:2022)

Plastiques - Détermination des propriétés en traction - Partie 4: Conditions d'essai pour

les composites plastiques renforcés de fibres isotropes et orthotropes (ISO/FDIS 527-

4:2022)
Ta slovenski standard je istoveten z: prEN ISO 527-4
ICS:
83.120 Ojačani polimeri Reinforced plastics
oSIST prEN ISO 527-4:2023 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 527-4:2023
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oSIST prEN ISO 527-4:2023
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 527-4
ISO/TC 61/SC 13
Plastics — Determination of tensile
Secretariat: JISC
properties —
Voting begins on:
2022-12-02
Part 4:
Voting terminates on:
Test conditions for isotropic and
2023-02-24
orthotropic fibre-reinforced plastic
composites
Plastiques — Détermination des propriétés en traction —
Partie 4: Conditions d'essai pour les composites plastiques renforcés
de fibres isotropes et orthotropes
ISO/CEN PARALLEL PROCESSING
RECIPIENTS OF THIS DRAFT ARE INVITED TO
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
DOCUMENTATION.
IN ADDITION TO THEIR EVALUATION AS
Reference number
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 527-4:2022(E)
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
NATIONAL REGULATIONS. © ISO 2022
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)
FINAL
INTERNATIONAL ISO/FDIS
DRAFT
STANDARD 527-4
ISO/TC 61/SC 13
Plastics — Determination of tensile
Secretariat: JISC
properties —
Voting begins on:
Part 4:
Voting terminates on:
Test conditions for isotropic and
orthotropic fibre-reinforced plastic
composites
Plastiques — Détermination des propriétés en traction —
Partie 4: Conditions d'essai pour les composites plastiques renforcés
de fibres isotropes et orthotropes
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022
ISO/CEN PARALLEL PROCESSING

All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may

be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting on

the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below

or ISO’s member body in the country of the requester.
RECIPIENTS OF THIS DRAFT ARE INVITED TO
ISO copyright office
SUBMIT, WITH THEIR COMMENTS, NOTIFICATION
OF ANY RELEVANT PATENT RIGHTS OF WHICH
CP 401 • Ch. de Blandonnet 8
THEY ARE AWARE AND TO PROVIDE SUPPOR TING
CH-1214 Vernier, Geneva
DOCUMENTATION.
Phone: [phone]
IN ADDITION TO THEIR EVALUATION AS
Reference number
Email: [e-mail]
BEING ACCEPTABLE FOR INDUSTRIAL, TECHNO-
ISO/FDIS 527-4:2022(E)
Website: www.iso.org
LOGICAL, COMMERCIAL AND USER PURPOSES,
DRAFT INTERNATIONAL STANDARDS MAY ON
Published in Switzerland
OCCASION HAVE TO BE CONSIDERED IN THE
LIGHT OF THEIR POTENTIAL TO BECOME STAN-
DARDS TO WHICH REFERENCE MAY BE MADE IN
© ISO 2022 – All rights reserved
NATIONAL REGULATIONS. © ISO 2022
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)
Contents Page

Foreword ........................................................................................................................................................................................................................................iv

Introduction .................................................................................................................................................................................................................................v

1 Scope ................................................................................................................................................................................................................................. 1

2 Normative references ..................................................................................................................................................................................... 1

3 Terms and definitions .................................................................................................................................................................................... 1

4 Principle ........................................................................................................................................................................................................................ 5

5 Apparatus .................................................................................................................................................................................................................... 5

6 Test specimens ....................................................................................................................................................................................................... 5

6.1 Shape and dimensions ..................................................................................................................................................................... 5

6.2 Preparation of specimens .......................................................................................................................................................... 10

6.2.1 General ..................................................................................................................................................................................... 10

6.2.2 End tabs for type 3 specimens ............................................................................................................................ 10

6.2.3 Applications of end tabs for type 3 specimens ..................................................................................... 10

6.3 Gauge marks .......................................................................................................................................................................................... 10

6.4 Checking the specimens .............................................................................................................................................................. 10

6.5 Anisotropy ............................................................................................................................................................................................... 11

7 Number of specimens ........................................................................................................................................... ........................................11

8 Conditioning ..........................................................................................................................................................................................................11

9 Procedure .................................................................................................................................................................................................................11

9.1 Test atmosphere ................................................................................................................................................................................. 11

9.2 Measurement of specimen dimensions ......................................................................................................................... 11

9.3 Clamping ................................................................................................................................................................................................... 11

9.4 Prestresses ........................................................................................................................................... ................................................... 11

9.5 Setting of extensometers and strain gauges and placing of gauge marks ...................................... 11

9.6 Speed of testing ...................................................................................................................................................................................12

9.6.1 For type 1B test specimens ....................................................................................................................................12

9.6.2 For type 2, type 3 and type 4 test specimens ........................................................................................12

9.7 Recording of data ..............................................................................................................................................................................12

10 Calculation and expression of results ........................................................................................................................................12

10.1 Calculation of all properties for parallel sided specimens ...........................................................................12

10.2 Failure location related calculation of tensile strength for type 4 specimens ...........................12

11 Precision ....................................................................................................................................................................................................................12

12 Test report ...............................................................................................................................................................................................................12

Annex A (informative) Alignment of specimens ..................................................................................................................................14

Annex B (informative) Testing with tapered tensile specimen geometry without tabs (type

4) ........................................................................................................................................................................................................................................16

Annex C (informative) Unbonded tabs or gripping condition without tabs using fine grip

face ...................................................................................................................................................................................................................................19

Annex D (normative) Specimen preparation for type 2 and type 3 ................................................................................22

Annex E (normative) Failure location related calculation of tensile strength for type 4

specimens .................................................................................................................................................................................................................24

Bibliography .............................................................................................................................................................................................................................28

iii
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(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.

The procedures used to develop this document and those intended for its further maintenance are

described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the

different types of ISO documents should be noted. This document was drafted in accordance with the

editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).

Attention is drawn to the possibility that some of the elements of this document may be the subject of

patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of

any patent rights identified during the development of the document will be in the Introduction and/or

on the ISO list of patent declarations received (see www.iso.org/patents).

Any trade name used in this document is information given for the convenience of users and does not

constitute an endorsement.

For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and

expressions related to conformity assessment, as well as information about ISO's adherence to

the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see

www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 13,

Composites and reinforcement fibres, in collaboration with the European Committee for Standardization

(CEN) Technical Committee CEN/TC 249, Plastics, in accordance with the Agreement on technical

cooperation between ISO and CEN (Vienna Agreement).

This third edition cancels and replaces the second edition (ISO 527-4:2021), of which it constitutes a

minor revision.
The main changes are as follows:
— symbols Figures 1 and 5 have been updated to match the text;

— symbols in Table B.2 have been updated for consistency (upper case to lower case);

— symbols in Annex E have been updated for consistency (upper case to lower case);

— a reference has been added to the bibliography.
A list of all parts in the ISO 527 series can be found on the ISO website.

Any feedback or questions on this document should be directed to the user’s national standards body. A

complete listing of these bodies can be found at www.iso.org/members.html.
© ISO 2022 – All rights reserved
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)
Introduction

This document introduces a new test specimen, type 4, with a tapered geometry for use without

end tabs. The geometry has been developed to overcome difficulties with bonding end-tabbed test

specimens, especially when testing materials based on a thermoplastic matrix.
Guidance on gripping, including grip face design, is also added.
© ISO 2022 – All rights reserved
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oSIST prEN ISO 527-4:2023
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oSIST prEN ISO 527-4:2023
FINAL DRAFT INTERNATIONAL STANDARD ISO/FDIS 527-4:2022(E)
Plastics — Determination of tensile properties —
Part 4:
Test conditions for isotropic and orthotropic fibre-
reinforced plastic composites
1 Scope

This document specifies the test conditions for the determination of the tensile properties of isotropic

and orthotropic fibre-reinforced plastic composites, based upon the general principles given in

ISO 527-1.
NOTE 1 Unidirectional reinforced materials are covered by ISO 527-5.

The methods are used to investigate the tensile behaviour of the test specimens and for determining

the tensile strength, tensile modulus, Poisson's ratios and other aspects of the tensile stress-strain

relationship under the defined conditions.
The test method is suitable for use with the following materials:

— fibre-reinforced thermosetting and thermoplastic composites incorporating non-unidirectional

reinforcements such as mats, woven fabrics, woven rovings, chopped strands, combinations of such

reinforcements, hybrids, rovings, short or milled fibres or preimpregnated materials (prepregs);

NOTE 2 Injection moulded specimens are covered by ISO 527-2.

— combinations of the above with unidirectional reinforcements and multidirectional reinforced

materials constructed from unidirectional layers, provided such laminates are symmetrical;

NOTE 3 Materials with completely or mainly unidirectional reinforcements are covered by ISO 527-5.

— finished products made from materials mentioned above.

The reinforcement fibres covered include glass fibres, carbon fibres, aramid fibres and other similar

fibres.
2 Normative references

The following documents are referred to in the text in such a way that some or all of their content

constitutes requirements of this document. For dated references, only the edition cited applies. For

undated references, the latest edition of the referenced document (including any amendments) applies.

ISO 527-1:2019, Plastics — Determination of tensile properties — Part 1: General principles

ISO 1268 (all parts), Fibre-reinforced plastics — Methods of producing test plates

ISO 2818, Plastics — Preparation of test specimens by machining
ISO 16012, Plastics — Determination of linear dimensions of test specimens
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
© ISO 2022 – All rights reserved
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)

ISO and IEC maintain terminology databases for use in standardization at the following addresses:

— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
gauge length

initial distance between the gauge marks on the central part of the test specimen

Note 1 to entry: It is expressed in millimetres (mm).

Note 2 to entry: The values of the gauge length that are indicated for the specimen types in the different parts

of ISO 527 represent the maximum relevant gauge length.
[SOURCE: ISO 527-1:2019, 3.1]
3.2
thickness

smaller initial dimension of the rectangular cross-section in the central part of a test specimen

Note 1 to entry: It is expressed in millimetres (mm).
[SOURCE: ISO 527-1:2019, 3.2]
3.3
width

larger initial dimension of the rectangular cross-section in the central part of a test specimen

Note 1 to entry: It is expressed in millimetres (mm).
[SOURCE: ISO 527-1:2019, 3.3]
3.4
test speed
rate of separation of the gripping jaws
Note 1 to entry: It is expressed in millimetres per minute (mm/min).
[SOURCE: ISO 527-1:2019, 3.5]
3.5
stress

normal force per unit area of the original cross-section within the gauge length (3.1)

Note 1 to entry: It is expressed in megapascals (MPa).

Note 2 to entry: In order to differentiate from the true stress related to the actual cross-section of the specimen,

this stress is frequently called “engineering stress”.

Note 3 to entry: σ for “1"-direction specimens is defined as σ and for "2"-direction specimens as σ (see 3.9 and

1 2
Figure 2 for definitions of these directions).

[SOURCE: ISO 527-1:2019, 3.6, modified — Domain “” and Note 3 to entry has been added.]

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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)
3.5.1
strength
maximum stress observed during a tensile test
Note 1 to entry: It is expressed in megapascals (MPa).
[SOURCE: ISO 527-1:2019, 3.6.2]
3.6
strain
increase in length per unit original length of the gauge

Note 1 to entry: It is expressed as a dimensionless ratio, or as a percentage (%).

[SOURCE: ISO 527-1:2019, 3.7]
3.6.1
strain at strength
strain at which the strength (3.5.1) is reached

Note 1 to entry: It is expressed as a dimensionless ratio, or as a percentage (%).

[SOURCE: ISO 527-1:2019, 3.7.3]
3.7
tensile modulus
modulus of elasticity under tension

slope of the stress/strain curve σ(ε) in the interval between the two strains ε = 0,05 % and ε = 0,25 %

1 2
Note 1 to entry: It is expressed in megapascals (MPa).

Note 2 to entry: It may be calculated either as the chord modulus or as the slope of a linear least-squares

regression line in this interval.
Note 3 to entry: This definition does not apply to films.
Note 4 to entry: See Figure 1.
[SOURCE: ISO 527-1:2019, 3.9]
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)
Key
X strain, ε
Y stress, σ
a slope E
Figure 1 — Stress-strain curve
3.8
Poisson's ratio

negative ratio of the strain change Δε , in one of the two axes normal to the direction of extension,

to the corresponding strain change Δε in the direction of extension, within the linear portion of the

longitudinal versus normal strain curve
Note 1 to entry: It is expressed as a dimensionless ratio.

Note 2 to entry: Since the lateral strain change Δε is a negative number and the longitudinal strain change Δε is

n l

positive, the Poissons ratio as defined in ISO 527-1:2019, 3.10 is a positive number.

[SOURCE: ISO 527-1:2019, 3.10]
3.9
specimen coordinate axes
1, 2, 3

axes, where “1"-direction is normally defined in terms of a feature associated with the material

structure or the production process, such as the length direction in continuous-sheet processes (see

Figure 2) and the “2"-direction is perpendicular to the “1"-direction.

Note 1 to entry: The “1-direction is also referred to as the 0° or longitudinal direction and the “2’‘-direction as the

90° or transverse direction. The “3-direction” is perpendicular to the plane of the “1-direction” and “2-direction”.

The “3-direction” is also referred to as the “through-thickness” direction for planar systems.

Note 2 to entry: For unidirectional materials covered by part 5 of this International Standard, the direction

parallel to the fibres is defined as the “1"-direction and the direction perpendicular to the fibres (in the plane of

the prepreg/plate) as the “2"-direction.
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)
Figure 2 — Fibre-reinforced plastic composite showing axes of symmetry
3.10
failure position

failure location of specimen type 4 within the local coordinate system (u, v) of the tapered section

Note 1 to entry: It is expressed in millimetres (mm).
Note 2 to entry: See Figure 5.
4 Principle
According to ISO 527-1.
5 Apparatus

The apparatus shall conform to ISO 527-1:2019, Clause 5, except for the following.

The micrometre or its equivalent (see ISO 16012:2015, 5.5) shall read to 0,01 mm or better. It shall have

a suitable-size ball-ended anvil if used on irregular surfaces and a flat anvil if used on flat, smooth (e.g.

machined) surfaces.

When using extensometers with specimen type 4, use a gauge length of 25 mm (see ISO 527-1:2019,

5.1.5).

It is recommended to check alignment of the specimen and loading train as described in Annex A.

6 Test specimens
6.1 Shape and dimensions

Four types of test specimen are specified for use with this document, as detailed and illustrated in

Figure 3 (type 1 B), Figure 4 (types 2 and 3) and Figure 5 (type 4).

Type 1B is for testing fibre-reinforced thermoplastics. Type 1B specimens may also be used for

fibre-reinforced thermosets if they break within the gauge length. Type 1B shall not be used for

multidirectional, continuous-fibre-reinforced materials.
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)

Type 2 is rectangular without end-tabs, and Type 3 is rectangular with bonded end-tabs. They are

for testing fibre reinforced thermosets and thermoplastics. Specimens with unbonded end tabs are

considered as type 2.

The preferred width of type 2 and type 3 specimens is 25 mm, but widths of 50 mm or greater may be

used if the tensile strength is low due to the particular type of reinforcement used.

Type 4 is tapered without end-tabs and for testing fibre-reinforced composites, especially for testing

multidirectional, continuous-fibre reinforced thermoplastics. Please refer to Annex B.

The thickness of type 2, type 3 and type 4 specimens shall be between 2 mm and 10 mm.

To decide whether to use specimen with or without tabs, first carry out tests without using tabs

(specimen type 2 [rectangle] or type 4 [tapered]) and, if the tests are not successful, i.e. if almost all

specimens break in the grips (see Clause 7), perform test with bonded end tabs on the specimens

(specimen type 3). Refer to Annex C for guidance on unbonded tabs or gripping condition without tabs

using fine grip faces and careful control of the gripping force.

NOTE Continuous fibre reinforced composites typically have high fracture forces due to high tensile

strength of their fibres. Using specimen thicknesses larger than 4 mm can require an increased clamping length

to counter high clamping pressures.

The recommended specimen thickness for continuous-fibre-reinforced composites is 2 mm. For

compression-moulded materials, the thickness between the end-pieces of any type of specimen shall at

no point deviate from the mean by more than 2 %.
© ISO 2022 – All rights reserved
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)
Symbol Name Dimensions in millimetres
l Overall length ≥150
l Length of narrow parallel-sided portion 60,0 ± 0,5
r Radius ≥60
b Width at ends 20,0 ± 0,2
b Width of narrow portion 10,0 ± 0,2
h Thickness 2 to 10
L Gauge length (recommended for extensometers) 50,0 ± 0,5
L Initial distance between grips 115 ± 1

For some materials, the length of the tabs can be extended (e.g. so that l = 200 mm) to prevent breakage or slippage of

the specimen in the jaws.

It should be noted that a thickness of 4 mm gives a specimen which is identical to the type 1B specimen specified in

ISO 527-2.
Figure 3 — Type 1B specimen
a) Type 2 specimen
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)
b) Type 3 specimen
Key
1 centrings holes (optional), ϕ D
2 jaws
Symbol Name Dimensions in millimetres
Type 2 Type 3
L Overall length ≥250 ≥250
L Distance between end tabs — 150 ± 1
b Width 25 ± 0,5 or 50 ± 0,5 25 ± 0,5 or 50 ± 0,5
h Thickness 2 to 10 2 to 10
L Gauge length (recommended for extensometers) 50 ± 1 50 ± 1
L Initial distance between grips (nominal) 150 ± 1 150 ± 1
L Length of end tabs — ≥50
h Thickness of end tabs — 1 to 3
D Diameter of centring holes 3 ± 0,25 3 ± 0,25

NOTE Requirements on specimen quality and parallelism are given in ISO 527-1:2019, 6.4.

Figure 4 — Type 2 and type 3 specimens
© ISO 2022 – All rights reserved
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)
Symbol Name Dimensions in millimetres
Type 4
L Total length ≥300
b Width of parallel mid-section 25 ± 0,5
b Width at ends 28 ± 0,5
h Thickness 2 to 10
L Gauge length (recommended for extensometers) 25 ± 1
L Initial distance in between grips (nominal) 200
P Bézier curve control point in (u, v) coordinates (0; 0)
P Bézier curve control point in (u, v) coordinates (4,86; 0)
P Bézier curve control point in (u, v) coordinates (13,0; 0)
P Bézier curve control point in (u, v) coordinates (87,5; 1,5)
c Edge is a Bézier curve
j Clamping jaws

NOTE Requirements on specimen quality and parallelism are given in ISO 527-1:2019, 6.4.

Figure 5 — Type 4 specimen

Formulae (1) and (2) are the Bezier curve specifically resolved for the specimen type 4 to calculate a

polyline being applicable on most CNC machines. They define the local coordinates (u, v) of the tapered

section’s edge depicted in Figure 5. The transformation into the specimens coordinate system (x, y) is

depicted in Figure 5. The variable t should not exceed increments higher than 0,05 to avoid a course

partitioned polyline. A more detailed description on how to construct the type 4 specimen is given in

B.2.
ut()=+63,,08tt9841+ 45, 8t (1)
vt()=15, t (2)
with tw∈[]01,,itht Δ ≤ 005
© ISO 2022 – All rights reserved
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oSIST prEN ISO 527-4:2023
ISO/FDIS 527-4:2022(E)
6.2 Preparation of specimens
6.2.1 General

In the case of moulding and lamination materials, prepare a panel in accordance with ISO 1268 (all parts)

or another specified/agreed procedure. Cut individual specimens, or groups of specimens in the case of

type 3 specimens (see Annex D), from the panel.

In the case of finished products (for example, for quality control during manufacture or on delivery),

take specimens from flat areas.

Parameters for machining specimens shall be as specified in ISO 2818. Further guidance on cutting

specimens is given in Annex D.

For machining of type 4 specimens only, a polyline of the required profile can be calculated using the

Formulae (1) and (2).
6.2.2 End tabs for type 3 specimens

The ends of the specimen shall be reinforced, preferably with end tabs made of cross-ply or fabric glass-

fibre/resin laminate with the fibres at ±45° to the specimen axi
...