SIST EN ISO 527-1:2012

Plastics - Determination of tensile properties - Part 1: General principles (ISO 527-1:2012)

This part of ISO 527 specifies the general principles for determining the tensile properties of plastics and plastic composites under defined conditions. Several different types of test specimen are defined to suit different types of material which are detailed in subsequent parts of ISO 527. The methods are used to investigate the tensile behaviour of the test specimens and for determining the tensile strength, tensile modulus and other aspects of the tensile stress/strain relationship under the conditions defined. The methods are selectively suitable for use with the following materials: - rigid and semi-rigid (see 3.12 and 3.13, respectively) moulding, extrusion and cast thermoplastic materials, including filled and reinforced compounds in addition to unfilled types; rigid and semi-rigid thermoplastics sheets and films; - rigid and semi-rigid thermosetting moulding materials, including filled and reinforced compounds; rigid and semi-rigid thermosetting sheets, including laminates; - fibre-reinforced thermosets and thermoplastic composites incorporating unidirectional or non-unidirectional reinforcements, such as mat, woven fabrics, woven rovings, chopped strands, combination and hybrid reinforcement, rovings and milled fibres; sheet made from pre-impregnated materials (prepregs), - thermotropic liquid crystal polymers. The methods are not normally suitable for use with rigid cellular materials, for which ISO 1926 is used, or for sandwich structures containing cellular materials.

Kunststoffe - Bestimmung der Zugeigenschaften - Teil 1: Allgemeine Grundsätze (ISO 527-1:2012)

1.1   Dieser Teil von ISO 527 legt die allgemeinen Grundsätze zur Bestimmung der Zugeigenschaften von Kunststoffen und Kunststoff-Verbunden unter festgelegten Bedingungen fest. Mehrere verschiedene Probekörpertypen sind entsprechend den unterschiedlichen Werkstofftypen festgelegt, die in den folgenden Teilen von ISO 527 näher beschrieben werden.
1.2   Die Verfahren werden verwendet, um das Zugverformungsverhalten von Probekörpern zu untersuchen und die Zugfestigkeit, den Zugmodul und andere Gesichtspunkte der Zugspannungs-/Dehnungs-Beziehung unter festgelegten Bedingungen zu ermitteln.
1.3   Die Verfahren sind speziell zur Anwendung bei folgenden Werkstoffgruppen geeignet:
-   steife und halbsteife thermoplastische (siehe 3.12 und 3.13) Spritzguss-, Extrusions- und Gussform-massen einschließlich gefüllter und verstärkter Formmassen als Ergänzung zu ungefüllten Sorten; steife und halbsteife thermoplastische Platten und Folien;
-   steife und halbsteife duroplastische Formmassen einschließlich gefüllter und verstärkter Formmassen; steife und halbsteife duroplastische Platten einschließlich Schichtstoffe;
-   faserverstärkte duroplastische oder thermoplastische Verbundwerkstoffe mit unidirektionaler oder nichtunidirektionaler Verstärkung, wie Matten, Vliese und Gelege, Gewebe, Rovinggewebe, Kombinations- und Mischverstärkung, Stränge (Rovings) und Kurzfasern; Tafeln aus vorgetränkten Werkstoffen (Prepregs);
-   thermotrope flüssigkristalline Kunststoffe.
Die Verfahren sind üblicherweise nicht zur Anwendung mit harten Schaumstoffen, für die ISO 1926 angewendet wird, oder für Schichtstoff-Verbundwerkstoffen mit Schaumstoffkern geeignet.

Plastiques - Détermination des propriétés en traction - Partie 1: Principes généraux (ISO 527-1:2012)

L'ISO 527-1:2012 spécifie les principes généraux pour la détermination des propriétés en traction des plastiques et des composites en plastique dans des conditions définies. Plusieurs types différents d'éprouvettes sont définis en fonction des différents types de matériaux qui sont énumérés dans les parties suivantes de I'ISO 527.
Les méthodes sont utilisées pour étudier le comportement en traction des éprouvettes par la détermination de la résistance en traction, du module d'élasticité en traction et d'autres aspects de la relation contrainte/déformation en traction dans des conditions définies.
En principe, les méthodes ne peuvent pas être appliquées aux matériaux alvéolaires rigides, pour lesquels l'ISO 1926 est utilisée, ou aux structures sandwichs contenant des matériaux alvéolaires.

Polimerni materiali - Ugotavljanje nateznih lastnosti - 1. del: Splošna načela (ISO 527-1:2012)

Ta del standarda ISO 527 določa splošna načela za ugotavljanje nateznih lastnosti polimernih materialov in polimernih kompozitov pri določenih pogojih. Opredeljenih je več vrst preskušancev, da se zajamejo različne vrste materialov, ki so podrobno opisane v poznejših delih standarda ISO 527. Uporabljene so metode za preučevanje nateznih lastnosti preskušancev ter za ugotavljanje natezne trdnosti, nateznega modula in drugih vidikov razmerja natezna napetost/deformacija pri določenih pogojih. Metode so selektivno ustrezne za naslednje materiale: – trdi in poltrdi (glejte 3.12 in 3.13) plastomerni materiali za oblikovanje, ekstrudiranje in vlivanje, vključno s polnjenimi in ojačanimi spojinami poleg nepolnjenih vrst; trdi in poltrdi plastomerni trakovi in filmi; – trdi in poltrdi termoreaktivni materiali za oblikovanje, vključno s polnjenimi in ojačanimi spojinami; trdi in poltrdi termoreaktivni trakovi, vključno z laminati; – z vlakni ojačani termoreaktivni in plastomerni kompoziti, ki vsebujejo enosmerne ali večsmerne ojačitve, kot so mati, tkanine, tkani rovingi, rezane niti, kombinacijske in hibridne ojačitve, rovingi in brušena vlakna; trakovi iz predhodno impregniranih materialov; – termotropni polimeri iz tekočih kristalov. Metode običajno niso primerne za trde penjene materiale, za katere se uporablja standard ISO 1926, ali za strukture tipa »sendvič«, ki vsebujejo penjene materiale.

General Information

• Status: Withdrawn
• Public Enquiry End Date: 19-Jul-2010
• Publication Date: 22-Mar-2012
• Withdrawal Date: 30-Sep-2019
• ICS: 83.080.01 - Plastics in general
• Technical Committee: IPMA - Polimer materials and products
• Current Stage: 9900 - Withdrawal (Adopted Project)
• Start Date: 01-Oct-2019
• Due Date: 24-Oct-2019
• Completion Date: 01-Oct-2019
• Ref Project: EN ISO 527-1:2012 - Plastics - Determination of tensile properties - Part 1: General principles (ISO 527-1:2012)

Relations

• Replaced By: SIST EN ISO 527-1:2019 - Plastics - Determination of tensile properties - Part 1: General principles (ISO 527-1:2019)
• Effective Date: 25-Sep-2019
• Replaced By: SIST EN ISO 527-1:2019 - Plastics - Determination of tensile properties - Part 1: General principles (ISO 527-1:2019)
• Effective Date: 08-Jun-2022
• Replaces: SIST EN ISO 527-1:2000 - Plastics - Determination of tensile properties - Part 1: General principles (ISO 527-1:1993 including Corr 1:1994)
• Effective Date: 01-May-2012
• Revised: SIST EN ISO 527-1:2019 - Plastics - Determination of tensile properties - Part 1: General principles (ISO 527-1:2019)
• Effective Date: 23-May-2018

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO 527-1:2012
01-maj-2012
1DGRPHãþD
SIST EN ISO 527-1:2000
3ROLPHUQLPDWHULDOL8JRWDYOMDQMHQDWH]QLKODVWQRVWLGHO6SORãQDQDþHOD,62

Plastics - Determination of tensile properties - Part 1: General principles (ISO 527-
1:2012)
Kunststoffe - Bestimmung der Zugeigenschaften - Teil 1: Allgemeine Grundsätze (ISO
527-1:2012)
Plastiques - Détermination des propriétés en traction - Partie 1: Principes généraux (ISO
527-1:2012)
Ta slovenski standard je istoveten z: EN ISO 527-1:2012
ICS:
83.080.01 Polimerni materiali na Plastics in general
splošno
SIST EN ISO 527-1:2012 en,fr
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN ISO 527-1:2012

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SIST EN ISO 527-1:2012


EUROPEAN STANDARD
EN ISO 527-1

NORME EUROPÉENNE

EUROPÄISCHE NORM
February 2012
ICS 83.080.01 Supersedes EN ISO 527-1:1996
English Version
Plastics - Determination of tensile properties - Part 1: General
principles (ISO 527-1:2012)
Plastiques - Détermination des propriétés en traction - Kunststoffe - Bestimmung der Zugeigenschaften - Teil 1:
Partie 1: Principes généraux (ISO 527-1:2012) Allgemeine Grundsätze (ISO 527-1:2012)
This European Standard was approved by CEN on 14 February 2012.

CEN 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 CEN 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 CEN member into its own language and notified to the CEN-CENELEC Management Centre has the same
status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.





EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2012 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 527-1:2012: E
worldwide for CEN national Members.

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SIST EN ISO 527-1:2012
EN ISO 527-1:2012 (E)
Contents Page
Foreword .3

2

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SIST EN ISO 527-1:2012
EN ISO 527-1:2012 (E)
Foreword
This document (EN ISO 527-1:2012) has been prepared by Technical Committee ISO/TC 61 "Plastics" in
collaboration with Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by NBN.
This European Standard shall be given the status of a national standard, either by publication of an identical
text or by endorsement, at the latest by August 2012, and conflicting national standards shall be withdrawn at
the latest by August 2012.
Attention is drawn to the possibility that some of the elements of this document may be the subject of patent
rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 527-1:1996.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following
countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech
Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain,
Sweden, Switzerland, Turkey and the United Kingdom.
Endorsement notice
The text of ISO 527-1:2012 has been approved by CEN as a EN ISO 527-1:2012 without any modification.

3

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SIST EN ISO 527-1:2012

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SIST EN ISO 527-1:2012
INTERNATIONAL ISO
STANDARD 527-1
Second edition
2012-02-15
Plastics — Determination of tensile
properties —
Part 1:
General principles
Plastiques — Détermination des propriétés en traction —
Partie 1: Principes généraux
Reference number
ISO 527-1:2012(E)
©
ISO 2012

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SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2012
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 either ISO at the address below or ISO’s
member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail [e-mail]
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved

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SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Principle and methods . 5
4.1 Principle . 5
4.2 Method . 6
5 Apparatus . 6
5.1 Testing machine . 6
5.2 Devices for measuring width and thickness of the test specimens . 9
6 Test specimens . 9
6.1 Shape and dimensions . 9
6.2 Preparation of specimens . 9
6.3 Gauge marks .10
6.4 Checking the test specimens .10
6.5 Anisotropy .10
7 Number of test specimens .10
8 Conditioning . 11
9 Procedure . 11
9.1 Test atmosphere . 11
9.2 Dimensions of test specimen . 11
9.3 Gripping . 11
9.4 Prestresses .12
9.5 Setting of extensometers .12
9.6 Test speed .12
9.7 Recording of data .13
10 Calculation and expression of results .13
10.1 Stress .13
10.2 Strain .13
10.3 Tensile modulus .14
10.4 Poisson’s ratio .15
10.5 Statistical parameters .16
10.6 Significant figures .16
11 Precision .16
12 Test report .16
Annex A (informative) Determination of strain at yield.18
Annex B (informative) Extensometer accuracy for the determination of Poisson’s ratio .20
Annex C (normative) Calibration requirements for the determination of the tensile modulus .21
Bibliography .23
© ISO 2012 – All rights reserved iii

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SIST EN ISO 527-1:2012
ISO 527-1:2012(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 2.
The main task of technical committees is to prepare International Standards. 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.
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.
ISO 527-1 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 2, Mechanical properties.
This second edition cancels and replaces the first edition (ISO 527-1:1993), which has been technically revised.
It incorporates ISO 527-1:1993/Cor 1:1994 and ISO 527-1:1993/Amd 1:2005. The main changes are as follows.
— A method for the determination of Poisson’s ratio has been introduced. It is similar to the one used
in ASTM D638, but in order to overcome difficulties with precision of the determination of the lateral
contraction at small values of the longitudinal strain, the strain interval is extended far beyond the strain
region for the modulus determination.
— Definitions and methods have been optimized for computer controlled tensile test machines.
— The preferred gauge length for use on the multipurpose test specimen has been increased from 50 mm to
75 mm. This is used especially in ISO 527-2.
— Nominal strain and especially nominal strain at break will be determined relative to the gripping distance.
Nominal strain in general will be calculated as crosshead displacement from the beginning of the test,
relative to the gripping distance, or as the preferred method if multipurpose test specimens are used,
where strains up to the yield point are determined using an extensometer, as the sum of yield strain and
nominal strain increment after the yield point, the latter also relative to the gripping distance.
ISO 527 consists of the following parts, under the general title Plastics — Determination of tensile properties:
— Part 1: General principles
— Part 2 :Test conditions for moulding and extrusion plastics
— Part 3: Test conditions for films and sheets
— Part 4: Test conditions for isotropic and orthotropic fibre-reinforced plastic composites
— Part 5: Test conditions for unidirectional fibre-reinforced plastic composites
iv © ISO 2012 – All rights reserved

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SIST EN ISO 527-1:2012
INTERNATIONAL STANDARD ISO 527-1:2012(E)
Plastics — Determination of tensile properties —
Part 1:
General principles
1 Scope
1.1 This part of ISO 527 specifies the general principles for determining the tensile properties of plastics and
plastic composites under defined conditions. Several different types of test specimen are defined to suit different
types of material which are detailed in subsequent parts of ISO 527.
1.2 The methods are used to investigate the tensile behaviour of the test specimens and for determining the tensile
strength, tensile modulus and other aspects of the tensile stress/strain relationship under the conditions defined.
1.3 The methods are selectively suitable for use with the following materials:
— rigid and semi-rigid (see 3.12 and 3.13, respectively) moulding, extrusion and cast thermoplastic materials,
including filled and reinforced compounds in addition to unfilled types; rigid and semi-rigid thermoplastics
sheets and films;
— rigid and semi-rigid thermosetting moulding materials, including filled and reinforced compounds; rigid and
semi-rigid thermosetting sheets, including laminates;
— fibre-reinforced thermosets and thermoplastic composites incorporating unidirectional or non-unidirectional
reinforcements, such as mat, woven fabrics, woven rovings, chopped strands, combination and hybrid
reinforcement, rovings and milled fibres; sheet made from pre-impregnated materials (prepregs),
— thermotropic liquid crystal polymers.
The methods are not normally suitable for use with rigid cellular materials, for which ISO 1926 is used, or for
sandwich structures containing cellular materials.
2 Normative references
The following referenced documents are indispensable for the application 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 291, Plastics — Standard atmospheres for conditioning and testing
ISO 2602, Statistical interpretation of test results — Estimation of the mean — Confidence interval
ISO 7500-1:2004, Metallic materials — Verification of static uniaxial testing machines — Part 1:
Tension/compression testing machines — Verification and calibration of the force-measuring system
ISO 9513:1999, Metallic materials — Calibration of extensometers used in uniaxial testing
ISO 16012, Plastics — Determination of linear dimensions of test specimens
ISO 20753, Plastics — Test specimens
ISO 23529, Rubber — General procedures for preparing and conditioning test pieces for physical test methods
© ISO 2012 – All rights reserved 1

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SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
gauge length
L
0
initial distance between the gauge marks on the central part of the test specimen
NOTE 1 It is expressed in millimetres (mm).
NOTE 2 The values of the gauge length that are indicated for the specimen types in the different parts of ISO 527
represent the relevant maximum gauge length.
3.2
thickness
h
smaller initial dimension of the rectangular cross-section in the central part of a test specimen
NOTE It is expressed in millimetres (mm).
3.3
width
b
larger initial dimension of the rectangular cross-section in the central part of a test specimen
NOTE It is expressed in millimetres (mm).
3.4
cross-section
A
product of initial width and thickness, A = bh, of a test specimen.
2
NOTE It is expressed in square millimetres, (mm )
3.5
test speed
v
rate of separation of the gripping jaws
NOTE It is expressed in millimetres per minute (mm/min).
3.6
stress
σ
normal force per unit area of the original cross-section within the gauge length
NOTE 1 It is expressed in megapascals (MPa)
NOTE 2 In order to differentiate from the true stress related to the actual cross-section of the specimen, this stress is
frequently called “engineering stress”
3.6.1
stress at yield
σ
y
stress at the yield strain
NOTE 1 It is expressed in megapascals (MPa).
NOTE 2 It may be less than the maximum attainable stress (see Figure 1, curves b and c)
2 © ISO 2012 – All rights reserved

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SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
3.6.2
strength
σ
m
stress at the first local maximum observed during a tensile test
NOTE 1 It is expressed in megapascals (MPa).
NOTE 2 This may also be the stress at which the specimen yields or breaks (see Figure 1).
3.6.3
stress at x % strain
σ
x
stress at which the strain reaches the specified value x expressed as a percentage
NOTE 1 It is expressed in megapascals (MPa).
NOTE 2 Stress at x % strain may, for example, be useful if the stress/strain curve does not exhibit a yield point (see
Figure 1, curve d).
3.6.4
stress at break
σ
b
stress at which the specimen breaks
NOTE 1 It is expressed in megapascals (MPa).
NOTE 2 It is the highest value of stress on the stress-strain curve directly prior to the separation of the specimen, i.e
directly prior to the load drop caused by crack initiation.
3.7
strain
ε
increase in length per unit original length of the gauge.
NOTE It is expressed as a dimensionless ratio, or as a percentage (%).
3.7.1
strain at yield
yield strain
ε
y
the first occurrence in a tensile test of strain increase without a stress increase
NOTE 1 It is expressed as a dimensionless ratio, or as a percentage (%).
NOTE 2 See Figure 1, curves b and c.
NOTE 3 See Annex A (informative) for computer-controlled determination of the yield strain.
3.7.2
strain at break
ε
b
strain at the last recorded data point before the stress is reduced to less than or equal to 10 % of the strength
if the break occurs prior to yielding
NOTE 1 It is expressed as a dimensionless ratio, or as a percentage (%).
NOTE 2 See Figure 1, curves a and d.
3.7.3
strain at strength
ε
m
strain at which the strength is reached
NOTE It is expressed as a dimensionless ratio, or as a percentage (%).
© ISO 2012 – All rights reserved 3

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SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
3.8
nominal strain
ε
t
crosshead displacement divided by the gripping distance
NOTE 1 It is expressed as a dimensionless ratio, or as a percentage (%).
NOTE 2 It is used for strains beyond the yield strain (see 3.7.1) or where no extensometers are used.
NOTE 3 It may be calculated based on the crosshead displacement from the beginning of the test, or based on the
increment of crosshead displacement beyond the strain at yield, if the latter is determined with an extensometer (preferred
for multipurpose test specimens).
3.8.1
nominal strain at break
ε
tb
nominal strain at the last recorded data point before the stress is reduced to less than or equal to 10 % of the
strength if the break occurs after yielding
NOTE 1 It is expressed as a dimensionless ratio, or as a percentage (%).
NOTE 2 See Figure 1, curves b and c.
3.9
modulus
E
t
slope of the stress/strain curve σ(ε) in the strain interval between ε = 0,05 % and ε = 0,25 %
1 2
NOTE 1 It is expressed in megapascals (MPa).
NOTE 2 It may be calculated either as the chord modulus or as the slope of a linear least-squares regression line in this
interval (see Figure 1, curve d).
NOTE 3 This definition does not apply to films.
3.10
Poisson’s ratio
µ
negative ratio of the strain increment Δε , in one of the two axes normal to the direction of extension, to the
n
corresponding strain increment Δε in the direction of extension, within the linear portion of the longitudinal
l
versus normal strain curve
NOTE It is expressed as a dimensionless ratio.
3.11
gripping distance
L
initial length of the part of the specimen between the grips
NOTE It is expressed in millimetres (mm).
3.12
rigid plastic
plastic that has a modulus of elasticity in flexure (or, if that is not applicable, in tension) greater than 700 MPa
under a given set of conditions
3.13
semi-rigid plastic
plastic that has a modulus of elasticity in flexure (or, if that is not applicable, in tension) between 70 MPa and
700 MPa under a given set of conditions
4 © ISO 2012 – All rights reserved

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SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
ε
tm
ε ε
tb tb
σ , σ
m b
a
σ
b
σ , σ
b
y m
σ , σ
y m
c
σ
b
σ , σ
m b
d
σ
x
σ
2
σ
1
ε ε ε ε ε ε
1 2 m m m X % m
ε ε ε ε
b y y b
Figure 1 — Typical stress/strain curves
NOTE Curve (a) represents a brittle material, breaking without yielding at low strains. Curve (d) represents a soft
rubberlike material breaking at larger strains (>50 %).
4 Principle and methods
4.1 Principle
The test specimen is extended along its major longitudinal axis at a constant speed until the specimen fractures
or until the stress (load) or the strain (elongation) reaches some predetermined value. During this procedure,
the load sustained by the specimen and the elongation are measured.
© ISO 2012 – All rights reserved 5

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SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
4.2 Method
4.2.1 The methods are applied using specimens which may be either moulded to the chosen dimensions or
machined, cut or punched from finished and semi-finished products, such as mouldings, laminates, films and
extruded or cast sheet. The types of test specimen and their preparation are described in the relevant part of
ISO 527 typical for the material. In some cases, a multipurpose test specimen may be used. Multipurpose and
miniaturized test specimens are described in ISO 20753.
4.2.2 The methods specify preferred dimensions for the test specimens. Tests which are carried out on
specimens of different dimensions, or on specimens which are prepared under different conditions, may
produce results which are not comparable. Other factors, such as the speed of testing and the conditioning of
the specimens, can also influence the results. Consequently, when comparative data are required, these factors
shall be carefully controlled and recorded.
5 Apparatus
5.1 Testing machine
5.1.1 General
The machine shall comply with ISO 7500-1 and ISO 9513, and meet the specifications given in 5.1.2 to
5.1.6, as follows.
5.1.2 Test speeds
The tensile-testing machine shall be capable of maintaining the test speeds as specified in Table 1.
Table 1 — Recommended test speeds
Test speed Tolerance
v
%
mm/min
0,125
0,25
0,5
1 ±20
2
5
10
20
50
100
±10
200
300
500
5.1.3 Grips
Grips for holding the test specimen shall be attached to the machine so that the major axis of the test specimen
coincides with the direction of extension through the centre line of the grip assembly. The test specimen shall
be held such that slip relative to the gripping jaws is prevented. The gripping system shall not cause premature
fracture at the jaws or squashing of the specimen in the grips.
6 © ISO 2012 – All rights reserved

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SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
For the determination of the tensile modulus, it is essential that the strain rate is constant and does not change,
for example, due to motion in the grips. This is important especially if wedge action grips are used.
NOTE For the prestress, which might be necessary to obtain correct alignment (see 9.3) and specimen seating and
to avoid a toe region at the start of the stress/strain diagram, see 9.4.
5.1.4 Force indicator
The force measurement system shall comply with class 1 as defined in ISO 7500-1:2004.
5.1.5 Strain indicator
5.1.5.1 Extensometers
Contact extensometers shall comply with ISO 9513:1999, class 1. The accuracy of this class shall be attained
in the strain range over which measurements are being made. Non-contact extensometers may also be used,
provided they meet the same accuracy requirements.
The extensometer shall be capable of determining the change in the gauge length of the test specimen at any
time during the test. It is desirable, but not essential, that the instrument should record this change automatically.
The instrument shall be essentially free of inertia lag at the specified speed of testing.
For accurate determination of the tensile modulus E , an instrument capable of measuring the change of the
t
gauge length with an accuracy of 1 % of the relevant value or better shall be used. When using test specimens
of type 1A, this corresponds to a requirement of absolute accuracy of ±1,5 μm, for a gauge length of 75 mm.
Smaller gauge lengths lead to different accuracy requirements, see Figure 2.
NOTE Depending on the gauge length used, the accuracy requirement of 1 % translates to different absolute
accuracies for the determination of the elongation within the gauge length. For miniaturized specimens, these higher
accuracies might not be attainable, due to lack of appropriate extensometers (see Figure 2 )
Commonly used optical extensometers record the deformation taken at one broad test-specimen surface: In
the case of such a single-sided strain-testing method, ensure that low strains are not falsified by bending, which
may result from even faint misalignment and initial warpage of the test specimen, and which generates strain
differences between opposite surfaces of the test specimen. It is recommended to use strain-measurement
methods that average the strains of opposite sides of the test specimen. This is relevant for modulus
determination, but less so for measurement of larger strains.
5.1.5.2 Strain gauges
Specimens may also be instrumented with longitudinal strain gauges; the accuracy of which shall be 1 %
–6
of the relevant value or better. This corresponds to a strain accuracy of 20 x 10 (20 microstrains) for the
measurement of the modulus. The gauges, surface preparation and bonding agents should be chosen to
exhibit adequate performance on the subject material
5.1.6 Recording of data
5.1.6.1 General
The data acquisition frequency needed for the recording of data (force, strain, elongation) must be sufficiently
high in order to meet accuracy requirements.
5.1.6.2 Recording of strain data
The data acquisition frequency for recording of strain data depends on
— v the test speed, in mm/min;
— L /L the ratio between the gauge length and initial grip-to-grip separation;
0
© ISO 2012 – All rights reserved 7

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SIST
...

SLOVENSKI STANDARD
oSIST prEN ISO 527-1:2010
01-junij-2010
3ROLPHUQLPDWHULDOL'RORþDQMHQDWH]QLKODVWQRVWLGHO6SORãQDQDþHOD,62',6

Plastics - Determination of tensile properties - Part 1: General principles (ISO/DIS 527-
1:2010)
Kunststoffe - Bestimmung der Zugeigenschaften - Teil 1: Allgemeine Grundsätze
(ISO/FDIS 527-1:2010)
Plastiques - Détermination des propriétés en traction - Partie 1: Principes généraux
(ISO/DIS 527-1:2010)
Ta slovenski standard je istoveten z: prEN ISO 527-1
ICS:
83.080.01 Polimerni materiali na Plastics in general
splošno
oSIST prEN ISO 527-1:2010 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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oSIST prEN ISO 527-1:2010

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oSIST prEN ISO 527-1:2010


EUROPEAN STANDARD
DRAFT
prEN ISO 527-1
NORME EUROPÉENNE

EUROPÄISCHE NORM

April 2010
ICS 83.080.01 Will supersede EN ISO 527-1:1996
English Version
Plastics - Determination of tensile properties - Part 1: General
principles (ISO/DIS 527-1:2010)
Plastiques - Détermination des propriétés en traction - Kunststoffe - Bestimmung der Zugeigenschaften - Teil 1:
Partie 1: Principes généraux (ISO/DIS 527-1:2010) Allgemeine Grundsätze (ISO/FDIS 527-1:2010)
This draft European Standard is submitted to CEN members for parallel enquiry. It has been drawn up by the Technical Committee
CEN/TC 249.

If this draft becomes a European Standard, CEN 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.

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

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland,
Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.

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 supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.


EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2010 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN ISO 527-1:2010: E
worldwide for CEN national Members.

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oSIST prEN ISO 527-1:2010
prEN ISO 527-1:2010 (E)
Contents Page
Foreword .3

2

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oSIST prEN ISO 527-1:2010
prEN ISO 527-1:2010 (E)
Foreword
This document (prEN ISO 527-1:2010) has been prepared by Technical Committee ISO/TC 61 "Plastics" in
collaboration with Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by NBN.
This document is currently submitted to the parallel Enquiry.
This document will supersede EN ISO 527-1:1996.
Endorsement notice
The text of ISO/DIS 527-1:2010 has been approved by CEN as a prEN ISO 527-1:2010 without any
modification.

3

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oSIST prEN ISO 527-1:2010

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oSIST prEN ISO 527-1:2010
DRAFT INTERNATIONAL STANDARD ISO/DIS 527-1
ISO/TC 61/SC 2 Secretariat: AENOR
Voting begins on: Voting terminates on:
2010-04-08 2010-09-08
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION • МЕЖДУНАРОДНАЯ ОРГАНИЗАЦИЯ ПО СТАНДАРТИЗАЦИИ • ORGANISATION INTERNATIONALE DE NORMALISATION
Plastics — Determination of tensile properties —
Part 1:
General principles
Plastiques — Détermination des propriétés en traction —
Partie 1: Principes généraux
(Revision of first edition of ISO 527-1:1993, ISO 527-1:1993/Cor.1:1994 and ISO 527-1:1993/Amd.1:2005)
ICS 83.080.01

ISO/CEN PARALLEL PROCESSING
This draft has been developed within the International Organization for Standardization (ISO), and
processed under the ISO-lead mode of collaboration as defined in the Vienna Agreement.
This draft is hereby submitted to the ISO member bodies and to the CEN member bodies for a parallel
five-month enquiry.
Should this draft be accepted, a final draft, established on the basis of comments received, will be
submitted to a parallel two-month approval vote in ISO and formal vote in CEN.
In accordance with the provisions of Council Resolution 15/1993 this document is circulated in
the English language only.
Conformément aux dispositions de la Résolution du Conseil 15/1993, ce document est distribué
en version anglaise seulement.
To expedite distribution, this document is circulated as received from the committee secretariat.
ISO Central Secretariat work of editing and text composition will be undertaken at publication
stage.
Pour accélérer la distribution, le présent document est distribué tel qu'il est parvenu du
secrétariat du comité. Le travail de rédaction et de composition de texte sera effectué au
Secrétariat central de l'ISO au stade de publication.
THIS DOCUMENT IS A DRAFT CIRCULATED FOR COMMENT AND APPROVAL. IT IS THEREFORE SUBJECT TO CHANGE AND MAY NOT BE
REFERRED TO AS AN INTERNATIONAL STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS BEING ACCEPTABLE FOR INDUSTRIAL, TECHNOLOGICAL, COMMERCIAL AND USER PURPOSES, DRAFT
INTERNATIONAL STANDARDS MAY ON OCCASION HAVE TO BE CONSIDERED IN THE LIGHT OF THEIR POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN NATIONAL REGULATIONS.
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 SUPPORTING DOCUMENTATION.
©
International Organization for Standardization, 2010

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oSIST prEN ISO 527-1:2010
ISO/DIS 527-1
PDF disclaimer
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Reproduction may be subject to royalty payments or a licensing agreement.
Violators may be prosecuted.
©
ii ISO 2010 – All rights reserved

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oSIST prEN ISO 527-1:2010
ISO/DIS 527-1
Contents Page
Foreword . v
Introduction . vi
1 Scope . 1
2 Normative references . 2
3 Terms and definitions . 2
4 Principle . 5
5 Apparatus . 6
5.1 Testing machine . 6
5.1.1 General . 6
5.1.2 Test speeds . 6
5.1.3 Grips . 6
5.1.4 Force indicator . 6
5.1.5 Strain indicator . 7
5.1.6 Recording of data . 7
5.2 Devices for measuring width and thickness of the test specimens . 9
6 Test specimens . 9
6.1 Shape and dimensions . 9
6.2 Preparation of specimens. 9
6.3 Gage marks . 10
6.4 Checking the test specimens . 10
6.5 Anisotropy . 10
7 Number of test specimens. 11
8 Conditioning . 11
9 Procedure . 11
9.1 Test atmosphere . 11
9.2 Dimensions of test specimen . 11
9.3 Gripping . 12
9.4 Prestresses . 12
9.5 Setting of extensometers. 12
9.6 Test speed . 12
9.7 Recording of data . 13
10 Calculation and expression of results . 13
10.1 Stress . 13
10.2 Strain . 13
10.2.1 Strains up to a yield point . 13
10.2.2 Strains beyond a yield point (nominal strain) . 14
10.2.3 Nominal strains . 15
10.3 Tensile modulus . 15
10.3.1 Secant slope . 15
10.3.2 Regression slope . 15
10.4 Poisson's ratio . 16
10.5 Statistical parameters . 16
10.6 Significant figures . 16
11 Precision . 16
12 Test report . 16
© ISO 2010 – All rights reserved iii

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oSIST prEN ISO 527-1:2010
ISO/DIS 527-1
Annex A (informativ) Determination of strain at yield .18
Annex B (informativ) Extensometer accuracy for the determination of Poisson's ratio .21
Annex C (informativ) Calibration requirements for the determination of the tensile modulus
C.1 Introduction .22
C.2 Calibration Process .22
C.3 Calibration apparatus accuracy requirements .23
The calibration apparatus shall conform to the requirements given in ISO 9513, table 2 for class 0,2. .23
C.4 Report .23

iv © ISO 2010 – All rights reserved

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oSIST prEN ISO 527-1:2010
ISO/DIS 527-1
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 2.
The main task of technical committees is to prepare International Standards. 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.
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.
ISO 527-1 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 2, mechanical
properties.
This second edition cancels and replaces the first edition (ISO 527-1:1993), [of which has been technically
revised.
ISO 527 consists of the following parts, under the general title Plastics — Determination of tensile properties:
⎯ Part 1: General principles
⎯ Part 2 :Test conditions for moulding and extrusion plastics
⎯ Part 3: Test conditions for films and sheets:
⎯ Part 4: Test conditions for isotropic and orthotropic fibre-reinforced plastic composites
⎯ Part 5: Test conditions for unidirectional fibre-reinforced plastic composites
© ISO 2010 – All rights reserved v

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oSIST prEN ISO 527-1:2010
ISO/DIS 527-1
Introduction
This revision of ISO 527-1 has changed compared to the former version in the following aspects:
⎯ A method for the determination of of the Poisson ratio has been introduced. It is similar to the one used in
ASTM D638, but in order to overcome difficulties with precision of the determination of the lateral
contraction at small values of the longitudinal strain, the strain interval is extended far beyond the strain
region for the modulus determination.
⎯ Definitions and methods have been optimised for computer controlled tensile test machines.
⎯ The gage length for use on the multipurpose test specimen has been increased from 50 mm to 75 mm.
This will be used especially for Part 2 and be moved there. Part 1 will remain a general document.
⎯ For multipurpose test specimens the strain after yielding is calculated as the sum of the strain at yield,
determined with an extensometer, and the (nominal) strain increment, determined as post yield
crosshead displacement relative to a nominal gage length of also 75 mm. For QC-purposes and where
specified the continued use of 50 mm gage length is allowed
⎯ Stress at break and nominal strain will be reinstated as discussed in Rome


vi © ISO 2010 – All rights reserved

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oSIST prEN ISO 527-1:2010
DRAFT INTERNATIONAL STANDARD ISO/DIS 527-1

Plastics — Determination of tensile properties —
Part 1:
General principles
1 Scope
1.1 This part of ISO 527 specifies the general principles for determining the tensile properties of plastics
and plastic composites under defined conditions. Several different types of test specimen are defined to suit
different types of material which are detailed in subsequent parts of ISO 527.
1.2 The methods are used to investigate the tensile behaviour of the test specimens and for determining
the strength, tensile modulus and other aspects of the stress/strain relationship under the conditions defined.
1.3 The methods are selectively suitable for use with the following range of materials:
⎯ rigid and semi rigid thermoplastics (see NOTE) moulding, extrusion and cast materials, including filled an
reinforced compounds in addition to unfilled types; rigid and semi rigid thermoplastics sheets and films;
⎯ rigid and semi rigid thermosetting moulding materials, including filled and reinforced compounds; rigid and
semi rigid thermosetting sheets, including laminates;
⎯ fibre-reinforced thermoset and thermoplastics composites incorporating unidirectional or nonunidirectional
reinforcements such as mat, woven fabrics, woven rovings, chopped strands, combination and hybrid
reinforcement, rovings and milled fibres; sheet made from pre-impregnated materials (prepregs),
⎯ thermotropic liquid crystal polymers.
The methods are not normally suitable for use with rigid cellular materials or sandwich structures containing
cellular material. For rigid cellular materials see ISO 1926. Testing conditions of sandwich structures shall be
agreed upon by experts.
NOTE Semi rigid plastic: plastic that has a modulus of elasticity in flexure or, if that is not applicable, then in tension,
between 70 MPa and 700 MPa under stated conditions; rigid plastic: plastic that has a modulus of elasticity in flexure or, if
that is not applicable, then in tension, greater than 700 MPa under stated conditions.
1.4 The methods are applied using specimens which may be either moulded to the chosen dimensions or
machined, cut or punched from finished and semifinished products such as mouldings, laminates, films and
extruded or cast sheet. The types of test specimen and their preparation are described in the relevant part of
ISO 527 typical for the material. In some cases a multipurpose test specimen (See Normative references, ISO
3167 or ISO 20753) may be used. Miniaturized specimens are described in ISO 20753 (See Normative
references)
1.5 The methods specify preferred dimensions for the test specimens. Tests which are carried out on
specimens of different dimensions, or on specimens which are prepared under different conditions, may
produce results which are not comparable. Other factors, such as the speed of testing and the conditioning of
the specimens, can also influence the results. Consequently, when comparative data are required, these
factors must be carefully controlled and recorded.
1.6 For the purpose of this standard, the term “tensile” has been deleted for all stresses and strains
throughout the text. However, it shall be added when reporting data to avoid confusion with similar properties
obtained by different modes of deformation like bending or compression.
© ISO 2010 – All rights reserved 1

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oSIST prEN ISO 527-1:2010
ISO/DIS 527-1
2 Normative references
The following referenced documents are indispensable for the application 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 291 Plastics — Standard atmospheres for conditioning and testing.
ISO 1926 Rigid cellular plastics – Determination of tensile properties
ISO 2602 Statistical interpretation of test results — Estimation of the mean — Confidence interval.
ISO 3167 Plastics – Preparation and use of multipurpose test specimens
ISO 7500-1 Metallic materials - Verification of static uniaxial testing machines - Part 1: Tension/compression
testing machines - Verification and calibration of the force-measuring system
ISO 9513 Metallic materials -- Calibration of extensometers used in uniaxial testing
ISO 16012 Plastics – Determination of linear dimension of test specimens
ISO 20753 Plastics – Test specimens
ISO 23529: Rubber - General procedures for preparing and conditioning test pieces for physical test methods
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply
3.1
gage length, L :
0
Initial distance between the gage marks on the central part of the test specimen; see figures of the test
specimens in the relevant part of ISO 527.
NOTE 1 It is expressed in millimetres (mm).
NOTE 2 The values of the gage length that are indicated for the specimen types in the different parts of ISO 527
represent the relevant maximum gage length.
3.2
Thickness, h:
The smaller initial dimension of the rectangular cross section in the central part of a test specimen.
NOTE It is expressed in millimetres (mm).
3.3
Width, b:
The larger initial dimension of the rectangular cross section in the central part of a test specimen
NOTE It is expressed in millimetres (mm).
3.4
Cross section, A:
The product of initial width and thickness, A=bh.
2
NOTE It is expressed in square millimetres, (mm )
2 © ISO 2010 – All rights reserved

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oSIST prEN ISO 527-1:2010
ISO/DIS 527-1
3.5
Test speed, v:
Rate of separation of the gripping jaws of the testing machine during the test.
NOTE It is expressed in millimetres per minute (mm/min).
3.6
σ
Stress,
Force per unit area of the original cross-section within the gage length, carried by the test specimen at any
given moment.
NOTE1 It is expressed in megapascals (MPa)
NOTE2 In order to differentiate from the true stress related to the actual cross section of the specimen this stress is
frequently called "engineering stress"
3.6.1
stress at yield, σ :
y
Stress at the yield strain (see figure 1, curves b and c).
NOTE 1 It is expressed in megapascals (MPa).
NOTE 2 It may be less than the maximum attainable stress (see figure 1, curve b
3.6.2
strength, σ :
m
Stress at the first occurrence of a stress maximum observed during a tensile test (see figure 1).
NOTE 1 It is expressed in megapascals (MPa).
NOTE 2 This may also be the stress at which the specimen yields or breaks.
3.6.3
stress at x% strain, σ :
x
stress at which the strain reaches the specified value x expressed as percentage
NOTE 1 It is expressed in megapascals (MPa).
NOTE 2 Stress at x% strain may e.g. be useful if the stress/strain curve does not exhibit a yield point (see figure 1, curve
d).
3.6.4
Stress at break, σ :
b
Stress at which the specimen breaks.
NOTE 1 It is expressed in megapascals (MPa).
NOTE 2 It is the highest value of stress on the stress-strain curve directly prior to the separation of the specimen, i.e
directly prior to the load drop caused by crack initiation.
3.7
strain, ε
Increase in length per unit original length of the gage.
NOTE It is expressed as a dimensionless ratio, or in percentage (%).
3.7.1
strain at yield, ε
y
the first occurrence in a tensile test of strain increase without a stress increase.(see 4.3.1 and figure 1, curves
b and c)
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oSIST prEN ISO 527-1:2010
ISO/DIS 527-1
NOTE 1 It is expressed as a dimensionless ratio, or in percentage (%).
NOTE 2 See Annex A (informative) for computer controlled determination of the yield strain
3.7.2
ε
strain at break,
B
strain at the last recorded data point before the stress is reduced to less or equal 10% of the strength if the
break occurs prior to yielding. See figure 1, curves a and d.
NOTE It is expressed as a dimensionless ratio, or in percentage (%).
3.7.4
strain at strength, ε
M
Strain at which the strength is reached.
NOTE It is expressed as a dimensionless ratio, or in percentage (%).
3.8
Nominal strain, ε
t
Strain determined as crosshead displacement relative to a specified gage length, see NOTE 3.
NOTE 1 It is expressed as a dimensionless ratio, or in percentage (%).
NOTE 2 It is used for strains beyond the yield point (see 3.7.1).
NOTE 3 For multipurpose test specimens the gage length is set to 75 mm, if the strains up to yield are also determined
with a gage length of 75 mm. If a gage length of 50 mm is used for QC purposes and product release or where specified
and for miniaturized specimens the gripping distance for calculating the nominal strain (increment) is used
NOTE 4 For multipurpose test specimens showing strains after yield points nominal strain is calculated as the sum of
(extensometer) strain at yield and nominal strain increment after yield. See equations 7 and 8
3.8.1
nominal strain at break, ε
tB
nominal strain at the last recorded data point before the stress is reduced to less or equal 10% of the strength
if the break occurs after yielding. See figure 1, curves b and c.
NOTE 1 It is expressed as a dimensionless ratio, or in percentage (%).
NOTE 2 For multipurpose test specimens it is the sum of the strain at yield and the increase in gripping distance after
the yield point per unit original length of the gage. See equations 7 and 8.
3.9
Tensile modulus E :
t
Slope of the stress stra
...