FprEN ISO 14556

Metallic materials - Charpy V-notch pendulum impact test - Instrumented test method (ISO/FDIS 14556:2023)

Metallische Werkstoffe - Kerbschlagbiegeversuch nach Charpy (V-Kerb) - Instrumentiertes Prüfverfahren (ISO/FDIS 14556:2023)

Dieses Dokument legt den instrumentierten Kerbschlagbiegeversuch nach Charpy (V-Kerb) für metallische Werkstoffe sowie die Anforderungen an die Mess- und Aufzeichnungseinrichtungen fest.
In Bezug auf den in ISO 148-1 beschriebenen Kerbschlagbiegeversuch nach Charpy ermöglicht der hier be-schriebene Versuch weitergehende Aussagen über das Bruchverhalten des untersuchten Erzeugnisses unter schlagartigen Beanspruchungsbedingungen.
Die Ergebnisse von instrumentierten Charpy-Prüfungen sind nicht direkt auf Konstruktionen oder Bauteile übertragbar und dürfen nicht direkt in Auslegungsberechnungen oder Sicherheitsbeurteilungen verwendet werden.
ANMERKUNG Allgemeine Angaben zum instrumentierten Kerbschlagbiegeversuch können den Literaturhinweisen [1] bis [5] entnommen werden.

Matériaux métalliques - Essai de flexion par choc sur éprouvette Charpy à entaille en V - Méthode d'essai instrumenté (ISO/FDIS 14556:2023)

Kovinski materiali - Udarni preskus žilavosti po Charpyju (V-zareza) - Instrumentirana preskusna metoda (ISOF/DIS 14556:2023)

General Information

• Status: Not Published
• Publication Date: 15-Jun-2023
• ICS: 77.040.10 - Mechanical testing of metals
• Technical Committee: ECISS/TC 101 - Test methods for steel (other than chemical analysis)
• Drafting Committee: ECISS/TC 101 - Test methods for steel (other than chemical analysis)
• Current Stage: 6055 - CEN Ratification completed (DOR) - Publishing
• Start Date: 16-Apr-2023
• Completion Date: 16-Apr-2023
• Ref Project: kSIST FprEN ISO 14556:2023 - Metallic materials - Charpy V-notch pendulum impact test - Instrumented test method (ISO/FDIS 14556:2023)

Relations

• Revises: EN ISO 14556:2015 - Metallic materials - Charpy V-notch pendulum impact test - Instrumented test method (ISO 14556:2015)
• Effective Date: 18-Jan-2023

Standards Content (Sample)

SLOVENSKI STANDARD
oSIST prEN ISO 14556:2022
01-maj-2022
Kovinski materiali - Udarni preskus žilavosti po Charpyju (V-zareza) -
Instrumentirana preskusna metoda (ISO/DIS 14556:2022)

Metallic materials - Charpy V-notch pendulum impact test - Instrumented test method

(ISO/DIS 14556:2022)
Metallische Werkstoffe - Kerbschlagbiegeversuch nach Charpy (V-Kerb) -
Instrumentiertes Prüfverfahren (ISO/DIS 14556:2022)

Matériaux métalliques - Essai de flexion par choc sur éprouvette Charpy à entaille en V -

Méthode d'essai instrumenté (ISO/DIS 14556:2022)
Ta slovenski standard je istoveten z: prEN ISO 14556
ICS:
77.040.10 Mehansko preskušanje kovin Mechanical testing of metals
oSIST prEN ISO 14556:2022 en,fr,de

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

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oSIST prEN ISO 14556:2022
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oSIST prEN ISO 14556:2022
DRAFT INTERNATIONAL STANDARD
ISO/DIS 14556
ISO/TC 164/SC 4 Secretariat: ANSI
Voting begins on: Voting terminates on:
2022-02-24 2022-05-19
Metallic materials — Charpy V-notch pendulum impact test
— Instrumented test method

Matériaux métalliques — Essai de flexion par choc sur éprouvette Charpy à entaille en V — Méthode

d'essai instrumenté
ICS: 77.040.10
This document is circulated as received from the committee secretariat.
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
ISO/CEN PARALLEL PROCESSING
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
Reference number
NATIONAL REGULATIONS.
ISO/DIS 14556:2022(E)
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. © ISO 2022
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oSIST prEN ISO 14556:2022
ISO/DIS 14556:2022(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2022

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.
ISO copyright office
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Phone: [phone]
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Website: www.iso.org
Published in Switzerland
© ISO 2022 – All rights reserved
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oSIST prEN ISO 14556:2022
ISO/DIS 14556:2022(E)
Contents Page

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

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

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

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

3.1 Characteristic values of force (see Figure 2) ............................................................................................................... 1

3.2 Characteristic values of displacement (see Figure 2) .......................................................................................... 2

3.3 Characteristic values of impact energy ............................................................................................................................ 2

4 Symbols and abbreviated terms..........................................................................................................................................................3

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

6 Apparatus .................................................................................................................................................................................................................... 4

7 Test piece ..................................................................................................................................................................................................................... 6

8 Test procedure .......................................................................................................................................................................................................6

9 Expression of results ....................................................................................................................................................................................... 6

9.1 General ........................................................................................................................................................................................................... 6

9.2 Evaluation of the force-displacement curve ................................................................................................................ 7

9.3 Determination of the characteristic values of force ......... ..................................................................................... 7

9.4 Determination of the characteristic values of displacement ........................................................................ 7

9.5 Determination of the characteristic values of impact energy ...................................................................... 9

10 Test report .................................................................................................................................................................................................................. 9

Annex A (informative) Examples of instrumented strikers ....................................................................................................11

Annex B (informative) Example of support block for the calibration of a 2 mm striker ..........................12

Annex C (informative) Formulae for the estimation of the proportion of ductile fracture

surface ........................................................................................................................................... ...............................................................................13

Annex D (normative) Instrumented Charpy V-notch pendulum impact testing of miniature

test pieces .................................................................................................................................................................................................................14

Bibliography .............................................................................................................................................................................................................................17

iii
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oSIST prEN ISO 14556:2022
ISO/DIS 14556:2022(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 on the meaning of ISO specific terms and expressions related to conformity

assessment, as well as information about ISO's adherence to the WTO principles in the Technical

Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information

The committee responsible for this document is ISO/TC 164, Mechanical testing of metals, Subcommittee

SC 4, Fatigue, fracture and toughness testing.

This third edition cancels and replaces the second edition (ISO 14556:2015), which has been technically

revised.
© ISO 2022 – All rights reserved
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oSIST prEN ISO 14556:2022
DRAFT INTERNATIONAL STANDARD ISO/DIS 14556:2022(E)
Metallic materials — Charpy V-notch pendulum impact test
— Instrumented test method
1 Scope

This International Standard specifies a method of instrumented Charpy V-notch pendulum impact

testing on metallic materials and the requirements concerning the measurement and recording

equipment.

With respect to the Charpy pendulum impact test described in ISO 148-1, this test provides further

information on the fracture behaviour of the product under impact testing conditions.

The results of instrumented Charpy test analyses are not directly transferable to structures or

components, and shall not be directly used in design calculations or safety assessments.

General information about instrumented impact testing can be found in Reference [1] to Reference [5].

2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

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

ISO 148-1, Metallic materials — Charpy pendulum impact test — Part 1: Test method

ISO 148-2, Metallic materials — Charpy pendulum impact test — Part 2: Verification of testing machines

ISO WD 148-4, Metallic materials — Charpy pendulum impact test — Part 4: Testing of miniature Charpy

test pieces
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1 Characteristic values of force (see Figure 2)
3.1.1
general yield force

with Reference to an idealized representation of the force-displacement curve (see diagrams of

column 2 in Figure 2), force at the transition point from the linearly increasing part, discarding inertia

peak(s), to the curved increasing part of the force-displacement curve

Note 1 to entry: It represents an approximation of the force at which yielding occurs across the entire test piece

ligament (see 9.3).
3.1.2
maximum force

with Reference to an idealized representation of the force-displacement curve (see diagrams of

column 2 in Figure 2), maximum force in the course of the force-displacement curve

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oSIST prEN ISO 14556:2022
ISO/DIS 14556:2022(E)
3.1.3
unstable crack initiation force

if applicable, force at the beginning of a steep drop in the force-displacement curve (unstable crack

initiation)
3.1.4
crack arrest force
if applicable, force at the end (arrest) of unstable crack propagation
3.2 Characteristic values of displacement (see Figure 2)
3.2.1
general yield displacement
displacement corresponding to the general yield force, F
3.2.2
displacement at maximum force
displacement corresponding to the maximum force, F
3.2.3
displacement at unstable crack initiation

if applicable, displacement corresponding to the force at unstable crack initiation, F

3.2.4
crack arrest displacement

if applicable, displacement corresponding to the force at the end (arrest) of unstable crack propagation,

3.2.5
total displacement
displacement at the end of the force-displacement curve
3.3 Characteristic values of impact energy
3.3.1
energy at maximum force
partial impact energy from s = 0 to s = s

Note 1 to entry: Calculated as the area under the force-displacement curve from s = 0 to s = s .

3.3.2
energy at unstable crack initiation
if applicable, partial impact energy from s = 0 to s = s

Note 1 to entry: Calculated as the area under the force-displacement curve from s = 0 to s = s .

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oSIST prEN ISO 14556:2022
ISO/DIS 14556:2022(E)
3.3.3
crack arrest energy
if applicable, partial impact energy from s =0 to s = s

Note 1 to entry: Calculated as the area under the force-displacement curve from s = 0 to s = s .

3.3.4
total impact energy
energy absorbed by the test piece during the test

Note 1 to entry: Calculated as the area under the force-displacement curve from s =0 to s = s .

4 Symbols and abbreviated terms

For the purposes of this document, the symbols and abbreviations given in Table 1 are applicable (see

also Figure 2 and Figure 3).
Table 1 — Symbols and designations
Symbol Designation Unit
f Output frequency limit Hz
F Force N
F Crack arrest force N
F General yield force N
F Unstable crack initiation force N
F Maximum force N
g Local acceleration due to gravity m/s
h Height of fall of the centre of strike of the pendulum (see ISO 148-2) m
KV Absorbed energy as defined in ISO 148-1 J
m Effective mass of the pendulum corresponding to its effective weight kg
s Displacement m
s Crack arrest displacement m
s General yield displacement m
s Displacement at unstable crack initiation m
s Displacement at maximum force m
s Total displacement m
t Time s
t Time at the beginning of deformation of the test piece s
t Signal rise time s
v Initial striker impact velocity m/s
v Striker impact velocity at time t m/s
W Crack arrest energy J
W Energy at unstable crack initiation J
W Energy at maximum force J
W Total impact energy J
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oSIST prEN ISO 14556:2022
ISO/DIS 14556:2022(E)
5 Principle

5.1 This test consists of measuring the impact force, in relation to the test piece bending displacement,

during an impact test carried out in accordance with ISO 148-1. The area under the force-displacement

curve is a measure of the energy absorbed by the test piece.

5.2 Force-displacement curves for different steel products and different temperatures can be quite

different, even though the areas under the curves and the absorbed energies are identical. If the force-

displacement curves are divided into characteristic parts, various phases of the test can be deduced

which provide considerable information about the behaviour of the test piece at impact loading rates.

6 Apparatus
6.1 Testing machine

A pendulum impact testing machine, in accordance with ISO 148-2, and instrumented to determine the

force-time or force-displacement curve shall be used.

Comparisons between the total impact energy, W , from the instrumentation (see Clause 9.5) and the

absorbed energy indicated by the machine dial or encoder, KV, shall be made.

NOTE The instrumentation and the machine dial or encoder measure similar but different quantities.

Differences are to be expected (see Reference [6]).

If deviations between KV and W exceed 10 % of KV, the following should be checked:

a) friction of the machine;
b) calibration of the measuring system;
c) software used;

d) the possibility of applying the so-called “dynamic force adjustment”, see Reference [7], whereby

forces are adjusted until W and KV become equal.
6.2 Instrumentation and calibration
6.2.1 Traceable measurement

The equipment used for all calibration measurements shall be traceable to national or international

standards of measurement.
6.2.2 Force measurement

Force measurement is usually achieved by using two active electric resistance strain gauges attached

to the standard striker to form a force transducer. Suitable designs are shown in Annex A.

A full bridge circuit is made by two equally stressed (active) strain gauges bonded to opposite sides of

the striker and by two compensating (passive) strain gauges, or by substitute resistors. Compensating

strain gauges shall not be attached to any part of the testing machine which experiences impact or

vibration effects.

NOTE 1 Alternately, any other instrumentation to form a force transducer, which meets the required

performance levels, may be used.

The force measuring system (instrumented striker, amplifier, recording system) shall have a response

of at least 100 kHz, which corresponds to a rise time, t , of no more than 3,5 µs.

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oSIST prEN ISO 14556:2022
ISO/DIS 14556:2022(E)

A simple dynamic assessment of the force measuring chain can be performed by measuring the

value of the first inertia peak. By experience, the dynamics of the measuring chain can be considered

satisfactory if a steel V-notch test piece shows an initial peak greater than 8 kN when using an impact

velocity between 5 m/s and 5,5 m/s. This is valid if the centres of the active strain gauges are 11 mm to

15 mm away from the striker contact point.

The instrumentation of the striker shall be adequate to give the required nominal force range. The

instrumented striker shall be designed to minimize its sensitivity to non-symmetric loading.

NOTE 2 Experience shows that with the V-notch test piece, nominal impact forces up to 40 kN can occur for

most steel types.
6.2.3 Calibration

Calibration of the recorder and measuring system may be performed statically in accordance with the

accuracy requirements given below and in 6.2.4.

It is recommended that the force calibration be performed with the striker built into the hammer

assembly.

Force is applied to the striker through a special load frame equipped with a calibrated load cell and

using a special support block in the position of the test piece.

The contact conditions shall be approximately equal to those of the test and give reproducible results.

NOTE An example of a suitable support block for the calibration of a 2 mm striker is given in Annex B.

The static linearity and hysteresis error of the built-in, instrumented striker, including all parts of the

measurement system up to the recording apparatus (printer, plotter, etc.), shall be within ±2 % of the

recorded force, between 50 % and 100 % of the nominal force range, and within ±1 % of the full scale

force value between 10 % and 50 % of the nominal force range (see Figure 1).

For the instrumented striker alone, it is recommended that the accuracy be ±1 % of the recorded value

between 10 % and 100 % of the nominal range.
Key
X recorded value as percentage of nominal range
Y absolute error as percentage of nominal range

Figure 1 — Maximum permissible error of recorded values within the nominal force range

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oSIST prEN ISO 14556:2022
ISO/DIS 14556:2022(E)
6.2.4 Displacement measurement
Displacement is normally determined from force-time measurements. See Clause 9.

Displacement can also be determined by non-contacting measurement of the displacement of the striker,

relative to the anvil, using optical, inductive, or capacitive methods. The signal transfer characteristics

of the displacement measurement system shall correspond to that of the force measuring system in

order to make the two recording systems synchronous.

The displacement measuring system shall be designed for nominal values up to 30 mm; linearity errors

in the measuring system shall yield measured values to within ±2 % in the range 1 mm to 30 mm. A

dynamic calibratio
...