EN ISO 10070:2019
(Main)Metallic powders - Determination of envelope-specific surface area from measurements of the permeability to air of a powder bed under steady-state flow conditions (ISO 10070:2019)
Metallic powders - Determination of envelope-specific surface area from measurements of the permeability to air of a powder bed under steady-state flow conditions (ISO 10070:2019)
This document specifies a method of measuring the air permeability and the porosity of a packed bed of metal powder, and of deriving therefrom the value of the envelope-specific surface area. The permeability is determined under steady-state flow conditions, using a laminar flow of air at a pressure near atmospheric. This document does not include the measurement of permeability by a constant volume method.
Several different methods have been proposed for this determination, and several test devices are available commercially. They give similar, reproducible results, provided that the general instructions given in this document are respected, and the test parameters are identical.
This document does not specify a particular commercial test device and corresponding test procedure. However, for the convenience of the user, an informative annex has been included (see Annex A) which is intended to give some practical information on three specific methods:
— the Lea and Nurse method, involving a test device which can be built in a laboratory (see A.1);
— the Zhang Ruifu method, using a similar test device (see A.2);
— the Gooden and Smith method, involving a test device which can be built in a laboratory but for which a commercial test device also exists. (Two types of commercial test device exist; one of these is no longer available for purchase, but is still being used, see A.3.)
These methods are given as examples only. Other test devices available in various countries are acceptable within the scope of this document.
This testing method is applicable to all metallic powders, including powders for hardmetals, up to 1 000 µm in diameter, but it is generally used for particles having diameters between 0,2 µm and 75,0 µm. It is not intended to be used for powders composed of particles whose shape is far from equiaxial, i.e. flakes or fibres, unless specifically agreed upon between the parties concerned.
This testing method is not applicable to mixtures of different metallic powders or powders containing binders or lubricant.
If the powder contains agglomerates, the measured surface area can be affected by the degree of agglomeration. If the powder is subjected to a de-agglomeration treatment (see Annex B), the method used is to be agreed upon between the parties concerned.
Metallpulver - Bestimmung der spezifischen Außenoberfläche durch Messung der Permeabilität von Luft in einem Pulverbett unter gleichförmigen Strömungsbedingungen (ISO 10070:2019)
Dieses Dokument legt ein Verfahren zur Messung der Luftpermeabilität und der Porosität eines verdichteten Pulverbetts und daraus die Ableitung des Wertes für die spezifische Außenoberfläche fest. Die Permeabilität wird unter gleichförmigen Strömungsbedingungen mithilfe eines laminaren Luftstromes bei nahezu atmosphärischem Druck bestimmt. Dieses Dokument umfasst nicht die Messung der Permeabilität mithilfe des Verfahrens bei konstantem Volumen.
Für diese Bestimmung wurden mehrere unterschiedliche Verfahren vorgeschlagen und viele kommerzielle Prüfgeräte stehen zur Verfügung. Sie ergeben ähnliche, wiederholbare Ergebnisse, vorausgesetzt, die allgemeinen Anweisungen dieses Dokuments werden eingehalten und die Prüfparameter sind identisch.
Dieses Dokument behandelt kein bestimmtes kommerzielles Prüfgerät mit dem dazugehörigen Prüfverfahren. Trotzdem ist zur besseren Benutzerfreundlichkeit ein informativer Anhang mit praktischen Hinweisen zu drei spezifischen Verfahren angefügt (siehe Anhang A):
- das Verfahren nach Lea und Nurse, einschließlich eines Prüfgeräts, das in einem Labor aufgebaut werden kann (siehe A.1);
- das Verfahren nach Zhang Ruifu mit ähnlichem Prüfgerät (siehe A.2);
- das Verfahren nach Gooden und Smith, einschließlich eines Prüfgeräts, das in einem Labor aufgebaut werden kann, für das aber auch ein kommerzielles Prüfgerät existiert. (Es stehen zwei kommerzielle Prüfgeräte zur Verfügung; eines davon ist nicht mehr käuflich erwerbbar, wird jedoch nach wie vor eingesetzt – siehe A.3).
Diese Verfahren sind lediglich Beispiele. Innerhalb des Anwendungsbereiches dieses Dokuments sind auch andere Prüfgeräte, die in den verschiedenen Ländern zur Verfügung stehen, zulässig.
Dieses Prüfverfahren ist für alle Metallpulver, einschließlich Hartmetallpulver, mit einem Teilchendurchmesser bis 1 000 µm anwendbar, wird aber im Allgemeinen für Pulverteilchen mit einem Durchmesser von 0,2 µm bis 75,0 µm angewendet. Es dient nicht dazu, bei Pulvern angewendet zu werden, deren Pulverteilchen stark von der äquiaxialen Form abweichen, d. h. flocken- und nadelförmig, außer das wurde zwischen den beteiligten Parteien speziell vereinbart.
Dieses Prüfverfahren ist nicht anwendbar bei Gemischen aus verschiedenen Metallpulvern oder bei Pulvern, die Bindemittel oder Gleitmittel enthalten.
Wenn das Pulver Agglomerate enthält, kann die gemessene Oberfläche durch den Agglomerationsgrad beeinflusst sein. Wenn das Pulver einer Desagglomerationsbehandlung unterzogen wird (siehe Anhang B), muss das angewendete Verfahren zwischen den beteiligten Parteien vereinbart werden.
Poudres métalliques - Détermination de la surface spécifique d'enveloppe à partir de mesures de la perméabilité à l'air d'un lit de poudre dans des conditions d'écoulement permanent (ISO 10070:2019)
Le présent document spécifié une méthode de mesure de la perméabilité à l'air et de la porosité d'un lit de poudre métallique tassé, et permettant de déduire une valeur de la surface spécifique d'enveloppe. La perméabilité est déterminée dans des conditions d'écoulement permanent, à l'aide d'un débit d'air laminaire à une pression voisine de la pression atmosphérique. Le présent document ne traite pas de la mesure de la perméabilité à volume constant.
Plusieurs méthodes sont proposées pour remplir l'objectif fixé. De nombreux appareils d'essai, disponibles dans le commerce, permettent de mener à bien la détermination. Ces appareils d'essai donnent des résultats similaires et reproductibles dans la mesure où les instructions générales données dans le présent document sont respectées et où les paramètres d'essai identiques.
II n'est pas possible, dans le présent document, de se limiter à un appareil d'essai du commerce particulier et au mode opératoire d'essai correspondant. En vue d'aider néanmoins l'utilisateur, une annexe est prévue (voir Annexe A) pour donner des renseignements pratiques sur trois méthodes spécifiques:
— la méthode Lea et Nurse, impliquant un appareil d'essai conçu en laboratoire (voir A.1);
— la méthode Zhang Ruifu, utilisant un appareil d'essai similaire (voir A.2);
— la méthode Gooden et Smith impliquant un appareil d'essai qui peut être conçu en laboratoire, mais correspond aussi à un modèle du commerce. (Deux types d'appareil d'essai du commerce existent; l'un d'eux n'est plus disponible à l'achat, mais est toujours utilisé, voir A.3.
Ces méthodes sont données uniquement à titre d'exemple, mais n'excluent pas l'emploi d'autres matériels commercialisés dans certains pays et conformes au présent document.
La méthode d'essai est applicable à toutes les poudres métalliques, y compris les poudres de métaux durs, jusqu'à 1 000 μm de diamètre, mais est généralement réservée aux particules de diamètre comprises entre 0,2 et 75 μm. Elle n'est pas destinée à être utilisée pour les poudres composées de particules dont la forme s'écarte trop de I'équiaxialité, par exemple du type flocons ou fibres. Dans ce cas, il est admis de ne l'utiliser qu'avec le consentement de toutes les parties concernées.
La méthode d'essai n'est pas utilisable pour les mélanges de poudres métalliques différentes ou de poudres renfermant des liants ou lubrifiants.
Lorsque la poudre contient des agglomérats, la surface mesurée peut être affectée par le degré d'agglomération. Si la poudre est soumise à un traitement de désagglomération (voir Annexe B), la méthode utilisée doit être subordonnée à l'accord des parties concernées.
Kovinski prah - Ugotavljanje specifične ovojne površine z merjenjem zračne prepustnosti nasute plasti prašnih delcev pri ustaljenem toku zraka skoznjo (ISO 10070:2019)
Ta dokument določa metodo za merjenje zračne prepustnosti in poroznosti plasti kovinskega prahu in za izpeljevanje vrednosti specifične ovojne površine iz tega. Prepustnost se določa pod ustaljenimi pogoji pretoka, z uporabo laminarnega zračnega toka pri tlaku, ki je blizu atmosferskemu. Ta dokument ne vključuje merjenja prepustnosti po metodi konstantne prostornine. Za to ugotavljanje je bilo predlaganih več različnih metod in komercialno je na voljo več preskusnih naprav. Te naprave dajejo podobne rezultate z možnostjo reprodukcije pod pogojem, da se upoštevajo splošna navodila, podana v tem dokumentu, in da so preskusni parametri enaki. Ta dokument ne določa posebne komercialne preskusne naprave in ustreznega preskusnega postopka. Vendar je bil v pomoč uporabniku vključen informativni dodatek (glej dodatek A), katerega namen je podati nekaj praktičnih informacij glede treh specifičnih metod: – metoda Lea in Nurse, ki vključuje preskusno napravo, ki jo je mogoče izdelati v laboratoriju (glej A.1); – metoda Zhang Ruifu, pri kateri se uporablja podobna preskusna naprava (glej A.2); – metoda Gooden in Smith, ki vključuje preskusno napravo, ki jo je mogoče izdelati v laboratoriju, vendar zanjo obstaja tudi komercialna preskusna naprava. (Obstajata dva tipa komercialne preskusne naprave; eden od njiju ni več na voljo za nakup, a se še vedno uporablja, glej A.3.) Te metode so podane le kot primer. Druge preskusne naprave, ki so na voljo v različnih državah, so sprejemljive znotraj področja uporabe tega dokumenta. Ta metoda za preskušanje se uporablja za vse vrste kovinskega prahu, vključno s prahom za trde kovine, s premerom do 1000 μm, vendar se običajno uporablja za delce s premerom med 0,2 μm in 75,0 μm. Metoda ni namenjena za uporabo pri prahu, sestavljenem iz delcev, katerih oblika je daleč od enakoosne, tj. kosmi ali vlakna, razen če se glede tega zadevni stranki izrecno ne dogovorita drugače. Ta metoda za preskušanje se ne uporablja za mešanice različnega kovinskega prahu ali prahu, ki vsebuje veziva ali mazivo. Če prah vsebuje aglomerate, lahko stopnja aglomeracije vpliva na izmerjeno površino. Če prah ni izpostavljen deaglomeracijski obdelavi (glej dodatek B), se morata o uporabljeni metodi dogovoriti obe zadevni stranki.
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
01-marec-2020
Kovinski prah - Ugotavljanje specifične ovojne površine z merjenjem zračne
prepustnosti nasute plasti prašnih delcev pri ustaljenem toku zraka skoznjo (ISO
10070:2019)
Metallic powders - Determination of envelope-specific surface area from measurements
of the permeability to air of a powder bed under steady-state flow conditions (ISO
10070:2019)
Metallpulver - Ermittlung der spezifischen Außenoberfläche durch Messung der
Luftdurchlässigkeit einer Pulverprobe unter gleichförmigen Strömungsbedingungen (ISO
10070:2019)
Poudres métalliques - Détermination de la surface spécifique d'enveloppe à partir de
mesures de la perméabilité à l'air d'un lit de poudre dans des conditions d'écoulement
permanent (ISO 10070:2019)
Ta slovenski standard je istoveten z: EN ISO 10070:2019
ICS:
77.160 Metalurgija prahov Powder metallurgy
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EN ISO 10070
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2019
EUROPÄISCHE NORM
ICS 77.160
English Version
Metallic powders - Determination of envelope-specific
surface area from measurements of the permeability to air
of a powder bed under steady-state flow conditions (ISO
10070:2019)
Poudres métalliques - Détermination de la surface Metallpulver - Bestimmung der spezifischen
spécifique d'enveloppe à partir de mesures de la Außenoberfläche durch Messung der Permeabilität von
perméabilité à l'air d'un lit de poudre dans des Luft in einem Pulverbett unter gleichförmigen
conditions d'écoulement permanent (ISO 10070:2019) Strömungsbedingungen (ISO 10070:2019)
This European Standard was approved by CEN on 14 December 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, 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
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 10070:2019 E
worldwide for CEN national Members.
Contents Page
European foreword . 3
European foreword
This document (EN ISO 10070:2019) 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 June 2020, and conflicting national standards shall be
withdrawn at the latest by June 2020.
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.
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 10070:2019 has been approved by CEN as EN ISO 10070:2019 without any modification.
INTERNATIONAL ISO
STANDARD 10070
Second edition
2019-12
Metallic powders — Determination of
envelope-specific surface area from
measurements of the permeability to
air of a powder bed under steady-state
flow conditions
Poudres métalliques — Détermination de la surface spécifique
d'enveloppe à partir de mesures de la perméabilité à l'air d'un lit de
poudre dans des conditions d'écoulement permanent
Reference number
ISO 10070:2019(E)
©
ISO 2019
ISO 10070:2019(E)
© ISO 2019
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
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Published in Switzerland
ii © ISO 2019 – All rights reserved
ISO 10070:2019(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 3
5 General principles . 4
5.1 Permeability . 4
5.2 Carman-Arnell and Kozeny-Carman formulae . 4
5.3 General . 5
5.4 Envelope density . 5
6 Procedure. 6
6.1 Preparation of test portion . 6
6.2 Preparation of packed powder bed . 6
6.3 Determination . 6
7 Expression of results . 6
8 Test report . 7
Annex A (informative) Examples of methods of determining the permeability to air of a
powder bed . 8
Annex B (informative) Preliminary treatment of powder for de-agglomeration .17
Bibliography .18
ISO 10070:2019(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 second edition cancels and replaces the first edition (ISO 10070:1991), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— introduction of an automated test device based on the Gooden and Smith method, including
procedure and calibration.
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 10070:2019(E)
Introduction
The measurement of the permeability of a packed powder bed to a laminar gas flow is the basis of this
document. The determination can be made either at constant pressure drop (steady-state flow) or at
variable pressure drop (constant volume). This document deals only with determinations made under
steady-state flow conditions.
The permeability measured is influenced by the porosity of the powder bed. For a given particle shape,
the values of permeability and porosity can be used to calculate a specific surface area of the powder by
means of different formulae.
The surface area so calculated includes only those walls of the pores in the powder bed which are swept
by the gas flow. It does not take into account closed or blind pores. It is known as the envelope-specific
surface area. It can be very different from the total surface area of particles as measured, for instance,
by gas adsorption methods.
A single equation is used in the standard methods described in this document. It entails certain
limitations with respect to the type of powder (particle shape) and the porosity of the powder bed for
which the method is applicable. Consequently, this is not an absolute method, and the value obtained
depends upon the procedure
...
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