SIST EN ISO 15349-2:2021

SLOVENSKI STANDARD
01-oktober-2021
Nadomešča:
SIST EN ISO 15349-2:2003
Nelegirana jekla - Določevanje ogljika v majhnih količinah - 2. del: Metoda z
infrardečo absorpcijo po zgorevanju v indukcijski peči (s predgrevanjem) (ISO
15349-2:2021)
Unalloyed steel - Determination of low carbon content - Part 2: Infrared absorption
method after combustion in an induction furnace (with preheating) (ISO 15349-2:2021)
Unlegierter Stahl - Bestimmung niedriger Kohlenstoffgehalte - Teil 2: Verfahren mit
Infrarotabsorption nach Verbrennung im Induktionsofen (mit Vorwärmung) (ISO 15349-
2:2021)
Acier non alliés - Détermination des faibles teneurs en carbone - Partie 2: Méthode par
absorption dans l'infrarouge après combustion dans un four à induction (avec
préchauffage) (ISO 15349-2:2021)
Ta slovenski standard je istoveten z: EN ISO 15349-2:2021
ICS:
77.040.30 Kemijska analiza kovin Chemical analysis of metals
77.140.45 Nelegirana jekla Non-alloyed steels
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 15349-2
EUROPEAN STANDARD
NORME EUROPÉENNE
July 2021
EUROPÄISCHE NORM
ICS 77.080.20 Supersedes EN ISO 15349-2:2003
English Version
Unalloyed steel - Determination of low carbon content -
Part 2: Infrared absorption method after combustion in an
induction furnace (with preheating) (ISO 15349-2:2021)
Acier non alliés - Détermination des faibles teneurs en Unlegierter Stahl - Bestimmung niedriger
carbone - Partie 2: Méthode par absorption dans Kohlenstoffgehalte - Teil 2: Verfahren mit
l'infrarouge après combustion dans un four à induction Infrarotabsorption nach Verbrennung im
(avec préchauffage) (ISO 15349-2:2021) Induktionsofen (mit Vorwärmung) (ISO 15349-
2:2021)
This European Standard was approved by CEN on 11 July 2021.

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, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2021 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 15349-2:2021 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 15349-2:2021) has been prepared by Technical Committee ISO/TC 17 "Steel" in
collaboration with Technical Committee CEN/TC 459/SC 2 “Methods of chemical analysis for iron and
steel ” the secretariat of which is held by SIS.
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 January 2022, and conflicting national standards shall
be withdrawn at the latest by January 2022.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 15349-2:2003.
Any feedback and questions on this document should be directed to the users’ national standards
body/national committee. A complete listing of these bodies can be found on the CEN websites.
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, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 15349-2:2021 has been approved by CEN as EN ISO 15349-2:2021 without any
modification.
INTERNATIONAL ISO
STANDARD 15349-2
Second edition
2021-07
Unalloyed steel — Determination of
low carbon content —
Part 2:
Infrared absorption method after
combustion in an induction furnace
(with preheating)
Aciers non alliés — Détermination des faibles teneurs en carbone —
Partie 2: Méthode par absorption dans l'infrarouge après combustion
dans un four à induction (avec préchauffage)
Reference number
ISO 15349-2:2021(E)
©
ISO 2021
ISO 15349-2:2021(E)
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
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Published in Switzerland
ii © ISO 2021 – All rights reserved

ISO 15349-2:2021(E)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Reagents . 2
6 Apparatus . 3
7 Sampling and preparation of the test samples . 4
8 Procedure. 4
8.1 General . 4
8.2 Test portion . 5
8.3 Blank test . 5
8.4 Determination . 5
8.4.1 Pre-treatment of the test portion . 5
8.4.2 Combustion of the test portion . 6
8.5 Establishment of the calibration curve . 6
8.5.1 Calibration with sucrose standard solutions . 6
8.5.2 Calibration with calcium carbonate . 7
9 Expression of results . 7
9.1 Method of calculation . 7
9.2 Precision . 8
10 Test report . 8
Annex A (informative) Features of commercial induction furnaces and infrared carbon analysers 9
Annex B (informative) Additional information on the international inter-laboratory test .11
Annex C (informative) Graphical representation of precision data .12
Bibliography .13
ISO 15349-2:2021(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 1, Methods
of determination of chemical composition, in collaboration with the European Committee for
Standardization (CEN) Technical Committee CEN/TC 459/SC 2, Methods of chemical analysis for iron
and steel, in accordance with the Agreement on technical cooperation between ISO and CEN (Vienna
Agreement).
This second edition cancels and replaces the first edition (ISO 15349-2:1999), which has been
technically revised. The main changes compared to the previous edition are as follows:
— normative references have been revised;
— the precision data has been updated;
— the former Table B.3 has been deleted;
— the text has been improved editorially.
A list of all parts in the ISO 15349 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2021 – All rights reserved

INTERNATIONAL STANDARD ISO 15349-2:2021(E)
Unalloyed steel — Determination of low carbon content —
Part 2:
Infrared absorption method after combustion in an
induction furnace (with preheating)
1 Scope
This document specifies an infrared absorption method after combustion in an induction furnace for
the determination of the low carbon content in unalloyed steel.
The method is applicable to carbon contents between 0,000 3 % (mass fraction) and 0,009 % (mass
fraction).
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 648, Laboratory glassware — Single-volume pipettes
ISO 1042, Laboratory glassware — One-mark volumetric flasks
ISO 3696, Water for analytical laboratory use — Specification and test methods
ISO 14284, Steel and iron — Sampling and preparation of samples for the determination of chemical
composition
3 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at http:// www .electropedia .org/
4 Principle
Pre-heating of a test portion at low temperature followed by its combustion in presence of an accelerator
at a high temperature in an induction furnace in a current of pure oxygen.
Transformation of carbon into carbon dioxide and/or carbon monoxide.
Measurement by infrared absorption of the carbon dioxide and/or carbon monoxide evolved from the
sample and carried by a current of pure oxygen.
The calibration is carried out using sucrose or calcium carbonate.
ISO 15349-2:2021(E)
5 Reagents
During the analysis, unless otherwise stated, use only reagents of recognized analytical grade and only
water with a low content of organic matter, i.e. grade 2 water as specified in ISO 3696.
5.1 Water, free from carbon dioxide.
Boil water for 30 min, cool to room temperature and bubble oxygen (5.2) or a high purity inert gas
through it for 15 min. Prepare just before use.
5.2 Oxygen, minimum purity 99,95 % (volume fraction).
When the presence of organic contaminants is suspected in oxygen, an oxidation catalyst [copper(II)
oxide or platinum] tube heated to a temperature above 450 °C shall be used prior to the purifying unit.
The pressure of oxygen in the furnace is controlled by a pressure regulator designed especially for this
purpose.
5.3 Pure iron, containing less than 0,000 3 % (mass fraction) of carbon or having a very low and
known carbon content.
5.4 Solvent, appropriate for cleaning greasy or dirty test samples, for example, acetone.
5.5 Accelerator, common accelerators are copper, tungsten-tin mixture, iron, tungsten or nickel.
Copper, tungsten-tin mixture or tungsten containing less than 0,000 3 % carbon (mass fraction) may be
used.
Copper plate or pellet type tin and granular tungsten mixture containing less than 0,000 3 % (mass
fraction) of carbon or having a very low and known carbon content.
Plate shape or granular copper (about 0,1 g/plate) should be used after the following treatment. Heat
the copper plate at 450 °C to 600 °C for 10 min in a current of oxygen or air and cool in a desiccator
without grease. This treatment shall be carried out just before use.
If necessary, wash three times with acetone by decantation to remove organic contaminants and dry at
room temperature.
Pellet type tin (about 0,2 g/pellet) and granular tungsten, 1,68 mm (12 mesh) to 0,853 mm (20 mesh)
should be used after the following treatment. Heat the tungsten at 450 °C in air for 10 min and cool in
a desiccator without grease. Clean the tin for more than 5 min with hydrochloric acid in an ultrasonic
cleaner, rinse with water and dry in air. These treatments shall be carried out just before use.
5.6 Sucrose, standard solutions
Weigh, to the nearest 0,1 mg, the masses of sucrose (C H O ) indicated in Table 1, previously dried
12 22 11
at 100 °C to 105 °C for 2,5 h and cooled in a desiccator, and transfer to a series of seven 100 ml beakers.
Add 30 ml of water (5.1) to dissolve, transfer quantitatively into a series of 100 ml one-mark volumetric
flasks, dilute to the mark with water (5.1) and mix.
2 © ISO 2021 – All rights reserved

ISO 15349-2:2021(E)
Table 1 — Standard solution series of sucrose
Standard solution Mass of sucrose Corresponding mass of Carbon content in 1 g of
added carbon the test portion
reference number g
µg % mass fraction
a
1 0 0 0
2 0,010 0 4,21 0,000 42
3 0,025 0 10,53 0,001 05
4 0,060 0 25,26 0,002 53
5 0,120 0 50,53 0,005 05
6 0,180 0 75,79 0,007 58
7 0,240 0 101,1 0,010 11
a
Zero member.
5.7 Calcium carbonate
Dry calcium carbonate [minimum purity: 99,9 % (mass fraction)] at 180 °C for 1 h and cool in a
desiccator before use.
5.8 Magnesium perchlorate, anhydrous, [Mg(ClO ) ], particle size: from 0,7 mm to 2,0 mm.
4 2
Phosphorous pentoxide may also be used by some instrument manufacturers.
5.9 Inert ceramic (attapulgus clay), impregnated with sodium hydroxide, particle size: from 0,6 mm
to 1,2 mm.
6 Apparatus
The apparatus required for combustion in an inductio
...