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

ISO 527-1:2012 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 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
Publication Date
14-Feb-2012
Withdrawal Date
17-Sep-2019
Technical Committee
Drafting Committee
Current Stage
9960 - Withdrawal effective - Withdrawal
Completion Date
18-Sep-2019

Relations

Buy Standard

Standard
EN ISO 527-1:2012 - BARVE na pdf strani 15, natisnjeno za čitalnico
English language
30 pages
sale 10% off
Preview
sale 10% off
Preview
e-Library read for
1 day

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.

---------------------- Page: 1 ----------------------
SIST EN ISO 527-1:2012
---------------------- Page: 2 ----------------------
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.
---------------------- Page: 3 ----------------------
SIST EN ISO 527-1:2012
EN ISO 527-1:2012 (E)
Contents Page

Foreword ..............................................................................................................................................................3

---------------------- Page: 4 ----------------------
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.

---------------------- Page: 5 ----------------------
SIST EN ISO 527-1:2012
---------------------- Page: 6 ----------------------
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
---------------------- Page: 7 ----------------------
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 copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2012 – All rights reserved
---------------------- Page: 8 ----------------------
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
---------------------- Page: 9 ----------------------
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
---------------------- Page: 10 ----------------------
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
---------------------- Page: 11 ----------------------
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

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

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

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
product of initial width and thickness, A = bh, of a test specimen.
NOTE It is expressed in square millimetres, (mm )
3.5
test speed
rate of separation of the gripping jaws
NOTE It is expressed in millimetres per minute (mm/min).
3.6
stress
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
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
---------------------- Page: 12 ----------------------
SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
3.6.2
strength
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

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
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
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

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

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
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
---------------------- Page: 13 ----------------------
SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
3.8
nominal strain
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

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

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

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

corresponding strain increment Δε in the direction of extension, within the linear portion of the longitudinal

versus normal strain curve
NOTE It is expressed as a dimensionless ratio.
3.11
gripping distance
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
---------------------- Page: 14 ----------------------
SIST EN ISO 527-1:2012
ISO 527-1:2012(E)
ε ε
tb tb
σ , σ
m b
σ , σ
y m
σ , σ
y m
σ , σ
m b
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
---------------------- Page: 15 ----------------------
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
mm/min
0,125
0,25
0,5
1 ±20
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
---------------------- Page: 16 ----------------------
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

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 %

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;
© ISO 2012 – All rights reserved 7
---------------------- Page: 17 ----------------------
SIST
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.