EN ISO 4491-4:2019

SLOVENSKI STANDARD
01-julij-2019
Nadomešča:
SIST EN ISO 4491-4:2014
Kovinski prah - Ugotavljanje deleža kisika z redukcijskimi metodami - 4. del:
Skupni delež kisika z redukcijo-ekstrakcijo (ISO 4491-4:2019)
Metallic powders - Determination of oxygen content by reduction methods - Part 4: Total
oxygen by reduction-extraction (ISO 4491-4:2019)
Poudres métalliques - Dosage de l'oxygène par les méthodes de réduction - Partie 4:
Oxygène total par réduction-extraction (ISO 4491-4:2019)
Ta slovenski standard je istoveten z: EN ISO 4491-4:2019
ICS:
77.160 Metalurgija prahov Powder metallurgy
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 4491-4
EUROPEAN STANDARD
NORME EUROPÉENNE
May 2019
EUROPÄISCHE NORM
ICS 77.160 Supersedes EN ISO 4491-4:2013
English Version
Metallic powders - Determination of oxygen content by
reduction methods - Part 4: Total oxygen by reduction-
extraction (ISO 4491-4:2019)
Poudres métalliques - Dosage de l'oxygène par les
méthodes de réduction - Partie 4: Oxygène total par
réduction-extraction (ISO 4491-4:2019)
This European Standard was approved by CEN on 25 April 2019.

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, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, 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
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 4491-4:2019 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 4491-4:2019) has been prepared by Technical Committee ISO/TC 119 "Powder
metallurgy" in collaboration with Technical Committee CEN/SS M11 “Powder metallurgy” the
secretariat of which is held by CCMC.
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 November 2019, and conflicting national standards
shall be withdrawn at the latest by November 2019.
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 4491-4:2013.
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, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 4491-4:2019 has been approved by CEN as EN ISO 4491-4:2019 without any
modification.
INTERNATIONAL ISO
STANDARD 4491-4
Third edition
2019-04
Metallic powders — Determination
of oxygen content by reduction
methods —
Part 4:
Total oxygen by reduction-extraction
Poudres métalliques — Dosage de l'oxygène par les méthodes de
réduction —
Partie 4: Oxygène total par réduction-extraction
Reference number
ISO 4491-4:2019(E)
©
ISO 2019
ISO 4491-4:2019(E)
© ISO 2019
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 2019 – All rights reserved

ISO 4491-4:2019(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 1
5 Apparatus and materials. 2
6 Test portion . 3
7 Procedure. 3
7.1 General . 3
7.2 Blank test and calibration . 4
7.3 Test . 4
8 Expression of results . 4
8.1 Permissible tolerances . 4
8.2 Final result . 4
9 Test report . 4
Annex A (informative) Examples of conditions of extraction for selected metal powders .6
ISO 4491-4:2019(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 119, Powder metallurgy, Subcommittee
SC 2, Sampling and testing methods for powders (including powders for hardmetals).
This third edition cancels and replaces the second edition (ISO 4491-4:2013), of which it constitutes a
minor revision. The changes compared to the previous edition are as follows:
— addition of Clause 3 (Terms and definitions);
— Clause 6, changing from 0,1 mg to 0,000 1 g;
— changing carbon monoxide to CO and carbon dioxide to CO .
A list of all parts in the ISO 4491 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 2019 – All rights reserved

ISO 4491-4:2019(E)
Introduction
The determination of the oxygen content of metallic powders is of the utmost importance in many fields
of powder metallurgy.
The standard methods described in ISO 4491-2 and ISO 4491-3 do not give the total oxygen content of
the sample, as some oxygen-containing constituents are not reduced by hydrogen.
Therefore, a standard method for the determination of the total oxygen content is needed. The most
frequently used method is reduction-extraction. It can be carried out with various commercially
available instruments working according to different principles of extraction and measurement.
The results of the analysis depend on the type of equipment used and on the test parameters selected.
However, as indicated in Clauses 4 to 7, it is always possible, for a given type of metal powder, to optimize
the test conditions to obtain reproducible and accurate results with any of the commercially available
instruments, provided they are designed for testing the metal powder considered.
It is not possible to standardize one or more particular instruments. However, certain basic points of
procedure are considered for the analysis of metallic powders (see Clause 7).
NOTE The reduction-extraction method is also applicable to nitrogen determination and certain instruments
permit simultaneous measurement of oxygen and nitrogen contents. However, the determination of nitrogen is
not covered by this document.
INTERNATIONAL STANDARD ISO 4491-4:2019(E)
Metallic powders — Determination of oxygen content by
reduction methods —
Part 4:
Total oxygen by reduction-extraction
1 Scope
This document specifies a method for the determination of the total oxygen content of metallic powders
by reduction-extraction at high temperature.
By agreement, this method is also applicable to the determination of the total oxygen content of sintered
metal materials.
The method is applicable to all powders of metals, alloys, carbides, and mixtures thereof which are non-
volatile under the test conditions. The sample can be in powder or compact form.
The analysis is carried out on the powder as supplied, b
...