Additive manufacturing - Feedstock materials - Methods to characterize metal powders (ISO/ASTM 52907:2019)

This document provides technical specifications for metallic powders intended to be used in additive manufacturing and covers the following aspects:
—          documentation and traceability;
—          sampling;
—          particle size distribution;
—          chemical composition;
—          characteristic densities;
—          morphology;
—          flowability;
—          contamination;
—          packaging and storage.
This document does not deal with safety aspects.
In addition, this document gives specific requirements for used metallic powders in additive manufacturing.

Additive Fertigung - Ausgangswerkstoffe - Verfahren zur Charakterisierung von Metallpulvern (ISO /ASTM 52907:2019)

Dieses Dokument stellt technische Spezifikationen für Metallpulver zur Verfügung, die für die Nutzung bei der additiven Fertigung bestimmt sind und umfasst folgende Gesichtspunkte:
—   Dokumentation und Rückverfolgbarkeit;
—   Probenahme;
—   Teilchengrößenverteilung;
—   chemische Zusammensetzung;
—   Dichte;
—   Morphologie;
—   Fließfähigkeit;
—   Reinheitsgrad;
—   Verpackung und Lagerung.
Dieses Dokument behandelt keine Sicherheitsaspekte.
Darüber hinaus enthält dieses Dokument besondere Anforderungen an gebrauchte Metallpulver bei der additiven Fertigung.

Fabrication additive - Matières premières - Méthodes pour caractériser les poudres métalliques (ISO/ASTM 52907:2019)

Aditivna proizvodnja - Surovine - Metode za označevanje vrst kovinskega prahu (ISO/ASTM 52907:2019)

Ta mednarodni standard opisuje tehnične specifikacije za kovinske praške, namenjene za uporabo pri aditivni proizvodnji, in zajema naslednje vidike:
– dokumentacija in sledljivost
– vzorčenje
– porazdelitev velikosti delcev
– kemična sestava
– značilne gostote
– morfologija
– sipkost
– toplotne značilnosti
– čistost
– embalaža in shranjevanje
Ta mednarodni standard ne obravnava varnostnih vidikov.
Poleg tega ta mednarodni standard podaja določene zahteve za ponovno uporabljene kovinske
praške pri aditivni proizvodnji.

General Information

Status
Withdrawn
Publication Date
30-Mar-2020
Withdrawal Date
29-Jun-2020
Current Stage
6060 - Definitive text made available (DAV) - Publishing
Start Date
18-Dec-2019
Completion Date
18-Dec-2019

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Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN ISO/ASTM 52907:2020
01-marec-2020
Aditivna proizvodnja - Surovine - Metode za označevanje vrst kovinskega prahu
(ISO/ASTM 52907:2019)

Additive manufacturing - Feedstock materials - Methods to characterize metal powders

(ISO/ASTM 52907:2019)
Additive Fertigung - Ausgangswerkstoffe - Verfahren zur Charakterisierung von
Metallpulvern (ISO /ASTM 52907:2019)

Fabrication additive - Matières premières - Méthodes pour caractériser les poudres

métalliques (ISO/ASTM 52907:2019)
Ta slovenski standard je istoveten z: EN ISO/ASTM 52907:2019
ICS:
25.030 3D-tiskanje Additive manufacturing
77.160 Metalurgija prahov Powder metallurgy
SIST EN ISO/ASTM 52907:2020 en,fr,de

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

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SIST EN ISO/ASTM 52907:2020
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SIST EN ISO/ASTM 52907:2020
EN ISO/ASTM 52907
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2019
EUROPÄISCHE NORM
ICS 25.030
English Version
Additive manufacturing - Feedstock materials - Methods to
characterize metal powders (ISO/ASTM 52907:2019)

Fabrication additive - Matières premières - Méthodes Additive Fertigung - Technische Spezifikationen für

pour caractériser les poudres métalliques (ISO/ASTM Metallpulver (ISO/ASTM 52907:2019)

52907:2019)
This European Standard was approved by CEN on 26 July 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/ASTM 52907:2019 E

worldwide for CEN national Members.
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SIST EN ISO/ASTM 52907:2020
EN ISO/ASTM 52907:2019 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

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SIST EN ISO/ASTM 52907:2020
EN ISO/ASTM 52907:2019 (E)
European foreword

This document (EN ISO/ASTM 52907:2019) has been prepared by Technical Committee ISO/TC 261

"Additive manufacturing" in collaboration with Technical Committee CEN/TC 438 “Additive

Manufacturing” the secretariat of which is held by AFNOR.

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/ASTM 52907:2019 has been approved by CEN as EN ISO/ASTM 52907:2019 without

any modification.
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SIST EN ISO/ASTM 52907:2020
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SIST EN ISO/ASTM 52907:2020
INTERNATIONAL ISO/ASTM
STANDARD 52907
First edition
2019-11
Additive manufacturing — Feedstock
materials — Methods to characterize
metal powders
Fabrication additive — Matières premières — Méthodes pour
caractériser les poudres métalliques
Reference number
ISO/ASTM 52907:2019(E)
ISO/ASTM International 2019
---------------------- Page: 7 ----------------------
SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO/ASTM International 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 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. In the United States, such requests should be sent to ASTM International.

ISO copyright office ASTM International
CP 401 • Ch. de Blandonnet 8 100 Barr Harbor Drive, PO Box C700
CH-1214 Vernier, Geneva West Conshohocken, PA 19428-2959, USA
Phone: +41 22 749 01 11 Phone: +610 832 9634
Fax: +41 22 749 09 47 Fax: +610 832 9635
Email: copyright@iso.org Email: khooper@astm.org
Website: www.iso.org Website: www.astm.org
Published in Switzerland
ii © ISO/ASTM International 2019 – All rights reserved
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SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(E)
Contents Page

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

Introduction ..................................................................................................................................................................................................................................v

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

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

3 Terms and definitions ..................................................................................................................................................................................... 2

4 Technical specifications ................................................................................................................................................................................ 2

4.1 General ........................................................................................................................................................................................................... 2

4.2 Documentation and traceability .............................................................................................................................................. 2

4.3 Sampling ....................................................................................................................................................................................................... 3

4.4 Particle size distribution ................................................................................................................................................................ 3

4.5 Chemical composition ...................................................................................................................................................................... 5

4.6 Characteristic densities ................................................................................................................................................................... 6

4.7 Morphology ................................................................................................................................................................................................ 7

4.8 Flowability .................................................................................................................................................................................................. 7

4.9 Contamination ......................................................................................................................................................................................... 8

4.10 Packaging, handling and storage ............................................................................................................................................. 8

4.10.1 General...................................................................................................................................................................................... 8

4.10.2 Packaging and handling ............................................................................................................................................. 8

4.10.3 Storage ...................................................................................................................................................................................... 9

Annex A (informative) Examples of morphology ..................................................................................................................................10

Annex B (informative) Example of certificate ..........................................................................................................................................15

Bibliography .............................................................................................................................................................................................................................18

© ISO/ASTM International 2019 – All rights reserved iii
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SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(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 ISO/TC 261, Additive manufacturing, in cooperation with ASTM F 42,

Additive manufacturing technologies, on the basis of a partnership agreement between ISO and ASTM

International with the aim to create a common set of ISO/ASTM standards on additive manufacturing.

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/ASTM International 2019 – All rights reserved
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SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(E)
Introduction

The document aims to simplify the relation between the supplier and the customer for the supply of

metallic powder for additive manufacturing purpose whatever the process involved.

The document does not aim to develop new standards but provides a list of existing standards dedicated

to metallic powder that are suitable for additive manufacturing.
© ISO/ASTM International 2019 – All rights reserved v
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SIST EN ISO/ASTM 52907:2020
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SIST EN ISO/ASTM 52907:2020
INTERNATIONAL STANDARD ISO/ASTM 52907:2019(E)
Additive manufacturing — Feedstock materials — Methods
to characterize metal powders
1 Scope

This document provides technical specifications for metallic powders intended to be used in additive

manufacturing and covers the following aspects:
— documentation and traceability;
— sampling;
— particle size distribution;
— chemical composition;
— characteristic densities;
— morphology;
— flowability;
— contamination;
— packaging and storage.
This document does not deal with safety aspects.

In addition, this document gives specific requirements for used metallic powders in additive

manufacturing.
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 2591-1, Test sieving — Part 1: Methods using test sieves of woven wire cloth and perforated metal plate

ISO 3252, Powder metallurgy — Vocabulary

ISO 3923-1, Metallic powders — Determination of apparent density — Part 1: Funnel method

ISO 3923-2, Metallic powders — Determination of apparent density — Part 2: Scott volumeter method

ISO 3953, Metallic powders — Determination of tap density
ISO 3954, Powders for powder metallurgical purposes — Sampling
ISO 4497, Metallic powders — Determination or particle size by dry sieving
ISO 13320, Particle size analysis — Laser diffraction methods

ISO 13322-1, Particle size analysis — Image analysis methods — Part 1: Static image analysis methods

ISO 13322-2, Particle size analysis — Image analysis methods — Part 2: Dynamic image analysis methods

ISO 22412, Particle size analysis — Dynamic light scattering (DLS)
© ISO/ASTM International 2019 – All rights reserved 1
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SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(E)

ISO/ASTM 52900, Additive manufacturing — General principles — Fundamentals and vocabulary

ASTM B212, Standard Test Method for Apparent Density of Free-Flowing Metal powders Using the Hall

Flowmeter Funnel
ASTM B214, Standard Test Method for Sieve Analysis of Metal powders
ASTM B215, Standard Practices for Sampling Metal powders
ASTM B243, Standard Terminology of Powder Metallurgy

ASTM B329, Standard Test Method for Apparent Density of Metal powders and Compounds Using the Scott

Volumeter

ASTM B417, Standard Test Method for Apparent Density of Non-Free-Flowing Metal powders Using the

Carney Funnel
ASTM B527, Standard Test Method for Tap Density of Metal powders and Compounds

ASTM B822, Standard Test Method for Particle Size Distribution of Metal powders and Related Compounds

by Light Scattering
EN 10204:2005, Metallic products — Types of inspection documents
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 3252, ISO/ASTM 52900,

ASTM B243 and the following apply.

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/
3.1
EDX

X-ray spectrometry in which the energy of individual photons is measured by a parallel detector and

used to build up a histogram representing the distribution of X-rays with energy

[SOURCE: ISO/TS 80004-13:2017, 3.3.2.4, modified — "EDX" has been kept as the only term and "are"

has been changed to "is"]
4 Technical specifications
4.1 General

The supplier and customer shall choose the test methods appropriate to the customer's requirements.

4.2 Documentation and traceability

To ensure traceability, statements of conformity and inspection documents shall specify the following:

— a unique document reference,
— the name and the address of the supplier,
— the reference of powder lot,

— the product description, including chemical composition, standard and/or trade/common name,

2 © ISO/ASTM International 2019 – All rights reserved
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SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(E)

— the nature of powder production process (including e.g. type of gas used, environment conditions),

— the packaging description, including the packaging, the nature of the shielding gas and the desiccant

bag, if relevant,
— the date of analysis,
— storage and preservation instructions,

— all of the information to ensure the traceability (e.g. order number, applicable specification).

NOTE 1 When a desiccant bag is in contact with the powder, it can be a source of contamination.

The inspection document shall comply with EN 10204:2005, 4.1.
The statement of conformity should follow ISO/IEC 17050-1.

The reported values shall be linked to the test method used and the corresponding standard. The

relevant standards to characterize metallic powder or feedstock for additive manufacturing are detailed

in this document. Powder characteristics shall be subjected to a prior customer/supplier agreement.

The product shall be supplied with its material safety data sheet (SDS).

NOTE 2 The inspection document and the statement of conformity can be on the same document.

EXAMPLES Product description: Ni alloy 718 powder 10 µm to 45 µm.
Nature of production process: Vacuum Induction Melting argon gas atomization.
Packaging description: 10 kg bottle under Argon protective atmosphere.
For an example of certificate, see Annex B.
4.3 Sampling

Samples shall be representative of the powder lot, ensuring homogeneity when split. Methods and

equipment shall follow the requirements in ISO 3954, ASTM B215 or another method subjected to a

prior customer/supplier agreement with the method(s) reported.

Procedures should be included for equipment cleanliness prior to sampling to prevent cross

contamination of powder.
4.4 Particle size distribution

Particle size and particle size distribution shall be determined in accordance with one or several of the

methods and standards listed in Table 1.

The standards according to the methods used shall be indicated in the report (see Annex B).

© ISO/ASTM International 2019 – All rights reserved 3
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SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(E)
Table 1 — Methods used for particle size analysis
Typical
range
(varies
Method Expression of results Advantages Limitations
between
instru-
ments)
Laser diffraction — Measurements shall
0,1 μm to
be made on isolated
— Ease of use
3 mm
Cumulative volume
(ISO 13320)
particles (not touching)
percentages on a plot,
— Large sample sizes – liquid suspension can
with calculated values
are not required be necessary
Light scattering
D at which X % of the
1 nm to
total volume is below
(ISO 22412,
— High accuracy and
0,1 mm — Assumes spherical
this value
ASTM B822)
repeatability
particles when
calculating volumes
— Measurements
shall be made on
isolated particles (not
touching) – liquid
suspension can be used
— Accounts for non-
Image analysis
Either the number or — Result accuracy
spherical particles
≥5 μm volume of particles in depends on number of
(static:
— Capable of reporting
each size interval pixels
ISO 13322-1)
shape factors
— Set up procedures to
be determined by the
operator to achieve
optimum results for
that specific powder
— Measurements shall
— Accounts for non- be made on isolated
spherical particles particles (not touching)
– liquid suspension can
— Capable of reporting
be necessary
shape factors
Either the number or
Image analysis
— Result accuracy
volume of particles in
— Large amount
≥5 μm depends on number of
(dynamic:
each size interval and
of particles can
pixels
ISO 13322-2)
shape distribution
be measured
in each sample, — Set up procedures to
which provides a be determined by the
large dataset for operator to achieve
statistical analysis optimum results for
that specific powder
4 © ISO/ASTM International 2019 – All rights reserved
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SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(E)
Table 1 (continued)
Typical
range
(varies
Method Expression of results Advantages Limitations
between
instru-
ments)
— Appropriate sieve sizes
required
— Results obtained
assume near spherical
particles that pass
through the sieve
openings when the
particle diameter is
— Equipment
smaller than the size
The amounts of
required is cheaper
openings. This does not
Sieving
particles present in
overall than
take into account long
specified particle size
(ISO 2591-
≥45 μm equipment required
particles or particles
intervals, expressed
1, ISO 4497,
for other particle
with aglomerations.
as a percentage of the
ASTM B214)
size distribution
total particles
testing methods — Carefully controlled
cleaning of sieves
between tests required
— Results obtained are
discrete intervals
— Not suitable for
particles sized wholly
or mostly under 45 μm

NOTE 1 The laser diffraction and dynamic image analysis method results in higher values than the sieving

method. The sieving method gives a weight percent of powder impeded by or passing through a square net

whereas the laser diffraction method gives an equivalent diameter calculated from laser interferences.

NOTE 2 The results can be obtained by different methods; for example, quantification of the largest particles

by sieving and quantification of the thinnest particles by laser diffraction. The results obtained from different

methods can produce different results.

NOTE 3 The results are often expressed in D10 (first decile, i.e. 1/10 of the statistical population is below this

value), D50 (median value, i.e. half of the statistical population is below this value) and D90 (last decile, i.e. 9/10

of the statistical population is below this value).

NOTE 4 Generally, the particle size distribution of used powder shifts with use. The degree of shift is a function

of multiple parameters including material and process.

NOTE 5 Particle size is considered to be a useful property for comparing and controlling different lots of

powder over time as this characteristic will change with powder use.
4.5 Chemical composition

The chemical composition of the metallic powder shall be determined by any suitable testing procedure,

e.g. wet chemical processes, atomic absorption spectrometry, flame emission spectroscopy, or X-ray

fluorescence analysis.

For powder mixtures, preparation of the sample for chemical analysis shall be performed in accordance

with recognised methods.
NOTE 1 Example of recognised methods are available in MPIF STM 67.
© ISO/ASTM International 2019 – All rights reserved 5
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SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(E)

Table 2 identifies examples of standards for determination of carbon, sulphur, oxygen, nitrogen and

hydrogen elements by various combustion and fusion techniques. The chemical composition shall be

determined on a sample that is representative of the lot used (or reused) for additive manufacturing.

Table 2 — Examples of testing standards for chemical composition of metals
Alloys\Elements Carbon Sulphur Oxygen Nitrogen Hydrogen
Steel and iron ISO 9556, or ISO 13902 or ISO 17053 or ISO 10720 and
ISO 15349-2 or ISO 15350 or ASTM E1019 ISO 15351 or
ISO 15350 or ASTM E1019 ASTM E1019
ASTM E1019
Titanium and ASTM E1941 ISO 22963 or ASTM E1409 ASTM E1447
titanium alloys ASTM E1409
Nickel and nickel ISO 7524 or ISO 7526 or ASTM E1019 ASTM E1019
alloys
ASTM E1019 ASTM E1019
Aluminum and ASTM E2792
aluminum alloys
Cobalt alloys ISO 11873 or ISO 11873 or ASTM E1019 ASTM E1019
ASTM E1019 ASTM E1019
Copper and copper ISO 7266 ASTM E2575
alloys

NOTE 2 Chemical composition can shift with powder recycling, e.g. oxygen level can increase with each reuse.

The applicability of standards listed in Table 2 needs to be checked for powders, and material grade

selected.
It can be necessary to use multiple testing procedures in combination.
The values shall be expressed in weight percentage.
Analysis method(s) should be reported with results.
4.6 Characteristic densities

Apparent and tap densities are useful powder characteristics, enabling the control of different powder

lots, or different powder mixtures from virgin and used powders over time, respectively.

Apparent density shall be determined by Hall funnel method according to ISO 3923-1 or ASTM B212 for

free flowing powder. For non-free flowing powder, the Carney funnel method according to ISO 3923-1

or ASTM B417 shall be used; for powders that do not flow freely through a Carney funnel, a Scott

apparatus according to ISO 3923-2 or ASTM B329 shall be used.

To determine the appropriate size of graduated cylinder used in tap density measurement, apparent

density should be measured first. Tap density shall be measured according to ISO 3953 or ASTM B527.

NOTE 1 In practice, the minimum number of taps, N, is determined such that no further change in volume takes

place. For all further tests on the same type of powder, the cylinder is subjected to 2N taps, except where general

experience and acceptance has established a specific number of taps (no less than N taps) as being satisfactory.

For fine refractory metallic powders, 3 000 taps has been found to be satisfactory for all sizes.

Skeletal density by gas pycnometry can be determined according to ISO 12154 or ASTM B923. The

skeletal density gives the true density of the material and can therefore be used to evaluate porosity level.

NOTE 2 SEM images of the powder after a sample preparation can give qualitative information only about

internal porosity. For example, see EN 1274.
6 © ISO/ASTM International 2019 – All rights reserved
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SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(E)
4.7 Morphology

Powder morphology is strongly linked to the process used to produce the powder; as stated and

illustrated in EN 1274. Particle morphology shall be described using the vocabulary defined in ISO 3252

or ASTM B243 (see Annex A for examples).

NOTE 1 Powder morphology is considered to be a useful property for comparing and controlling different lots

of powders over time.

In addition, qualitative image comparison and/or quantitative criteria can be subjected to a prior

customer/supplier agreement e.g. a quantitative shape factor defined as the maximum Feret’s diameter

divided by minimum Feret’s diameter, etc.
NOTE 2 The preferred method using SEM is secondary electron imaging.

Quantitative values shall be determined by automatic or semi-automatic methods with the number of

analysed particles being included in the report.

NOTE 3 A standard method for spreadability is under development within ISO/TC 261 and ASTM F 42.

Information on spreadability can be found in ASTM D7891.
4.8 Flowability

Powder flowability is a function of multiple factors, particularly the following:

— powder size distribution,

— cohesive strength by adsorbed water on the particles' surfaces from condensed, i.e. presence of

agglomerating forces such as capillary bridges formed by adsorbed water on particles’ surfaces

from condensed atmospheric vapour, electromagnetic forces in ferromagnetic materials, or Van der

Waals bonds,

— inter-particles friction, affected mostly by particles "surface roughness" and morphology of the

particle surfaces.

As moisture content is a key factor in determining flowability, where drying is required or prohibited

by the customer/supplier agreement or the selected flowability standard method (see list below), this

sha
...

SLOVENSKI STANDARD
SIST EN ISO/ASTM 52907:2020
01-marec-2020
Aditivna proizvodnja - Surovine - Metode za označevanje kovinskih praškov
(ISO/ASTM 52907:2019)

Additive manufacturing - Feedstock materials - Methods to characterize metal powders

(ISO/ASTM 52907:2019)
Additive Fertigung - Technische Spezifikationen für Metallpulver (ISO/ASTM
52907:2019)

Fabrication additive - Matières premières - Méthodes pour caractériser les poudres

métalliques (ISO/ASTM 52907:2019)
Ta slovenski standard je istoveten z: EN ISO/ASTM 52907:2019
ICS:
25.030 3D-tiskanje Additive manufacturing
77.160 Metalurgija prahov Powder metallurgy
SIST EN ISO/ASTM 52907:2020 en,fr,de

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

---------------------- Page: 1 ----------------------
SIST EN ISO/ASTM 52907:2020
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SIST EN ISO/ASTM 52907:2020
EN ISO/ASTM 52907
EUROPEAN STANDARD
NORME EUROPÉENNE
December 2019
EUROPÄISCHE NORM
ICS 25.030
English Version
Additive manufacturing - Feedstock materials - Methods to
characterize metal powders (ISO/ASTM 52907:2019)

Fabrication additive - Matières premières - Méthodes Additive Fertigung - Technische Spezifikationen für

pour caractériser les poudres métalliques (ISO/ASTM Metallpulver (ISO/ASTM 52907:2019)

52907:2019)
This European Standard was approved by CEN on 26 July 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,

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United Kingdom.
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© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO/ASTM 52907:2019 E

worldwide for CEN national Members.
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SIST EN ISO/ASTM 52907:2020
EN ISO/ASTM 52907:2019 (E)
Contents Page

European foreword ....................................................................................................................................................... 3

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SIST EN ISO/ASTM 52907:2020
EN ISO/ASTM 52907:2019 (E)
European foreword

This document (EN ISO/ASTM 52907:2019) has been prepared by Technical Committee ISO/TC 261

"Additive manufacturing" in collaboration with Technical Committee CEN/TC 438 “Additive

Manufacturing” the secretariat of which is held by AFNOR.

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/ASTM 52907:2019 has been approved by CEN as EN ISO/ASTM 52907:2019 without

any modification.
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SIST EN ISO/ASTM 52907:2020
INTERNATIONAL ISO/ASTM
STANDARD 52907
First edition
2019-11
Additive manufacturing — Feedstock
materials — Methods to characterize
metal powders
Fabrication additive — Matières premières — Méthodes pour
caractériser les poudres métalliques
Reference number
ISO/ASTM 52907:2019(E)
ISO/ASTM International 2019
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SIST EN ISO/ASTM 52907:2020
ISO/ASTM 52907:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO/ASTM International 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 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. In the United States, such requests should be sent to ASTM International.

ISO copyright office ASTM International
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Published in Switzerland
ii © ISO/ASTM International 2019 – All rights reserved
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Contents Page

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

Introduction ..................................................................................................................................................................................................................................v

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

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

3 Terms and definitions ..................................................................................................................................................................................... 2

4 Technical specifications ................................................................................................................................................................................ 2

4.1 General ........................................................................................................................................................................................................... 2

4.2 Documentation and traceability .............................................................................................................................................. 2

4.3 Sampling ....................................................................................................................................................................................................... 3

4.4 Particle size distribution ................................................................................................................................................................ 3

4.5 Chemical composition ...................................................................................................................................................................... 5

4.6 Characteristic densities ................................................................................................................................................................... 6

4.7 Morphology ................................................................................................................................................................................................ 7

4.8 Flowability .................................................................................................................................................................................................. 7

4.9 Contamination ......................................................................................................................................................................................... 8

4.10 Packaging, handling and storage ............................................................................................................................................. 8

4.10.1 General...................................................................................................................................................................................... 8

4.10.2 Packaging and handling ............................................................................................................................................. 8

4.10.3 Storage ...................................................................................................................................................................................... 9

Annex A (informative) Examples of morphology ..................................................................................................................................10

Annex B (informative) Example of certificate ..........................................................................................................................................15

Bibliography .............................................................................................................................................................................................................................18

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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 ISO/TC 261, Additive manufacturing, in cooperation with ASTM F 42,

Additive manufacturing technologies, on the basis of a partnership agreement between ISO and ASTM

International with the aim to create a common set of ISO/ASTM standards on additive manufacturing.

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/ASTM International 2019 – All rights reserved
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Introduction

The document aims to simplify the relation between the supplier and the customer for the supply of

metallic powder for additive manufacturing purpose whatever the process involved.

The document does not aim to develop new standards but provides a list of existing standards dedicated

to metallic powder that are suitable for additive manufacturing.
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SIST EN ISO/ASTM 52907:2020
INTERNATIONAL STANDARD ISO/ASTM 52907:2019(E)
Additive manufacturing — Feedstock materials — Methods
to characterize metal powders
1 Scope

This document provides technical specifications for metallic powders intended to be used in additive

manufacturing and covers the following aspects:
— documentation and traceability;
— sampling;
— particle size distribution;
— chemical composition;
— characteristic densities;
— morphology;
— flowability;
— contamination;
— packaging and storage.
This document does not deal with safety aspects.

In addition, this document gives specific requirements for used metallic powders in additive

manufacturing.
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 2591-1, Test sieving — Part 1: Methods using test sieves of woven wire cloth and perforated metal plate

ISO 3252, Powder metallurgy — Vocabulary

ISO 3923-1, Metallic powders — Determination of apparent density — Part 1: Funnel method

ISO 3923-2, Metallic powders — Determination of apparent density — Part 2: Scott volumeter method

ISO 3953, Metallic powders — Determination of tap density
ISO 3954, Powders for powder metallurgical purposes — Sampling
ISO 4497, Metallic powders — Determination or particle size by dry sieving
ISO 13320, Particle size analysis — Laser diffraction methods

ISO 13322-1, Particle size analysis — Image analysis methods — Part 1: Static image analysis methods

ISO 13322-2, Particle size analysis — Image analysis methods — Part 2: Dynamic image analysis methods

ISO 22412, Particle size analysis — Dynamic light scattering (DLS)
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ISO/ASTM 52900, Additive manufacturing — General principles — Fundamentals and vocabulary

ASTM B212, Standard Test Method for Apparent Density of Free-Flowing Metal powders Using the Hall

Flowmeter Funnel
ASTM B214, Standard Test Method for Sieve Analysis of Metal powders
ASTM B215, Standard Practices for Sampling Metal powders
ASTM B243, Standard Terminology of Powder Metallurgy

ASTM B329, Standard Test Method for Apparent Density of Metal powders and Compounds Using the Scott

Volumeter

ASTM B417, Standard Test Method for Apparent Density of Non-Free-Flowing Metal powders Using the

Carney Funnel
ASTM B527, Standard Test Method for Tap Density of Metal powders and Compounds

ASTM B822, Standard Test Method for Particle Size Distribution of Metal powders and Related Compounds

by Light Scattering
EN 10204:2005, Metallic products — Types of inspection documents
3 Terms and definitions

For the purposes of this document, the terms and definitions given in ISO 3252, ISO/ASTM 52900,

ASTM B243 and the following apply.

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/
3.1
EDX

X-ray spectrometry in which the energy of individual photons is measured by a parallel detector and

used to build up a histogram representing the distribution of X-rays with energy

[SOURCE: ISO/TS 80004-13:2017, 3.3.2.4, modified — "EDX" has been kept as the only term and "are"

has been changed to "is"]
4 Technical specifications
4.1 General

The supplier and customer shall choose the test methods appropriate to the customer's requirements.

4.2 Documentation and traceability

To ensure traceability, statements of conformity and inspection documents shall specify the following:

— a unique document reference,
— the name and the address of the supplier,
— the reference of powder lot,

— the product description, including chemical composition, standard and/or trade/common name,

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— the nature of powder production process (including e.g. type of gas used, environment conditions),

— the packaging description, including the packaging, the nature of the shielding gas and the desiccant

bag, if relevant,
— the date of analysis,
— storage and preservation instructions,

— all of the information to ensure the traceability (e.g. order number, applicable specification).

NOTE 1 When a desiccant bag is in contact with the powder, it can be a source of contamination.

The inspection document shall comply with EN 10204:2005, 4.1.
The statement of conformity should follow ISO/IEC 17050-1.

The reported values shall be linked to the test method used and the corresponding standard. The

relevant standards to characterize metallic powder or feedstock for additive manufacturing are detailed

in this document. Powder characteristics shall be subjected to a prior customer/supplier agreement.

The product shall be supplied with its material safety data sheet (SDS).

NOTE 2 The inspection document and the statement of conformity can be on the same document.

EXAMPLES Product description: Ni alloy 718 powder 10 µm to 45 µm.
Nature of production process: Vacuum Induction Melting argon gas atomization.
Packaging description: 10 kg bottle under Argon protective atmosphere.
For an example of certificate, see Annex B.
4.3 Sampling

Samples shall be representative of the powder lot, ensuring homogeneity when split. Methods and

equipment shall follow the requirements in ISO 3954, ASTM B215 or another method subjected to a

prior customer/supplier agreement with the method(s) reported.

Procedures should be included for equipment cleanliness prior to sampling to prevent cross

contamination of powder.
4.4 Particle size distribution

Particle size and particle size distribution shall be determined in accordance with one or several of the

methods and standards listed in Table 1.

The standards according to the methods used shall be indicated in the report (see Annex B).

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Table 1 — Methods used for particle size analysis
Typical
range
(varies
Method Expression of results Advantages Limitations
between
instru-
ments)
Laser diffraction — Measurements shall
0,1 μm to
be made on isolated
— Ease of use
3 mm
Cumulative volume
(ISO 13320)
particles (not touching)
percentages on a plot,
— Large sample sizes – liquid suspension can
with calculated values
are not required be necessary
Light scattering
D at which X % of the
1 nm to
total volume is below
(ISO 22412,
— High accuracy and
0,1 mm — Assumes spherical
this value
ASTM B822)
repeatability
particles when
calculating volumes
— Measurements
shall be made on
isolated particles (not
touching) – liquid
suspension can be used
— Accounts for non-
Image analysis
Either the number or — Result accuracy
spherical particles
≥5 μm volume of particles in depends on number of
(static:
— Capable of reporting
each size interval pixels
ISO 13322-1)
shape factors
— Set up procedures to
be determined by the
operator to achieve
optimum results for
that specific powder
— Measurements shall
— Accounts for non- be made on isolated
spherical particles particles (not touching)
– liquid suspension can
— Capable of reporting
be necessary
shape factors
Either the number or
Image analysis
— Result accuracy
volume of particles in
— Large amount
≥5 μm depends on number of
(dynamic:
each size interval and
of particles can
pixels
ISO 13322-2)
shape distribution
be measured
in each sample, — Set up procedures to
which provides a be determined by the
large dataset for operator to achieve
statistical analysis optimum results for
that specific powder
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Table 1 (continued)
Typical
range
(varies
Method Expression of results Advantages Limitations
between
instru-
ments)
— Appropriate sieve sizes
required
— Results obtained
assume near spherical
particles that pass
through the sieve
openings when the
particle diameter is
— Equipment
smaller than the size
The amounts of
required is cheaper
openings. This does not
Sieving
particles present in
overall than
take into account long
specified particle size
(ISO 2591-
≥45 μm equipment required
particles or particles
intervals, expressed
1, ISO 4497,
for other particle
with aglomerations.
as a percentage of the
ASTM B214)
size distribution
total particles
testing methods — Carefully controlled
cleaning of sieves
between tests required
— Results obtained are
discrete intervals
— Not suitable for
particles sized wholly
or mostly under 45 μm

NOTE 1 The laser diffraction and dynamic image analysis method results in higher values than the sieving

method. The sieving method gives a weight percent of powder impeded by or passing through a square net

whereas the laser diffraction method gives an equivalent diameter calculated from laser interferences.

NOTE 2 The results can be obtained by different methods; for example, quantification of the largest particles

by sieving and quantification of the thinnest particles by laser diffraction. The results obtained from different

methods can produce different results.

NOTE 3 The results are often expressed in D10 (first decile, i.e. 1/10 of the statistical population is below this

value), D50 (median value, i.e. half of the statistical population is below this value) and D90 (last decile, i.e. 9/10

of the statistical population is below this value).

NOTE 4 Generally, the particle size distribution of used powder shifts with use. The degree of shift is a function

of multiple parameters including material and process.

NOTE 5 Particle size is considered to be a useful property for comparing and controlling different lots of

powder over time as this characteristic will change with powder use.
4.5 Chemical composition

The chemical composition of the metallic powder shall be determined by any suitable testing procedure,

e.g. wet chemical processes, atomic absorption spectrometry, flame emission spectroscopy, or X-ray

fluorescence analysis.

For powder mixtures, preparation of the sample for chemical analysis shall be performed in accordance

with recognised methods.
NOTE 1 Example of recognised methods are available in MPIF STM 67.
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Table 2 identifies examples of standards for determination of carbon, sulphur, oxygen, nitrogen and

hydrogen elements by various combustion and fusion techniques. The chemical composition shall be

determined on a sample that is representative of the lot used (or reused) for additive manufacturing.

Table 2 — Examples of testing standards for chemical composition of metals
Alloys\Elements Carbon Sulphur Oxygen Nitrogen Hydrogen
Steel and iron ISO 9556, or ISO 13902 or ISO 17053 or ISO 10720 and
ISO 15349-2 or ISO 15350 or ASTM E1019 ISO 15351 or
ISO 15350 or ASTM E1019 ASTM E1019
ASTM E1019
Titanium and ASTM E1941 ISO 22963 or ASTM E1409 ASTM E1447
titanium alloys ASTM E1409
Nickel and nickel ISO 7524 or ISO 7526 or ASTM E1019 ASTM E1019
alloys
ASTM E1019 ASTM E1019
Aluminum and ASTM E2792
aluminum alloys
Cobalt alloys ISO 11873 or ISO 11873 or ASTM E1019 ASTM E1019
ASTM E1019 ASTM E1019
Copper and copper ISO 7266 ASTM E2575
alloys

NOTE 2 Chemical composition can shift with powder recycling, e.g. oxygen level can increase with each reuse.

The applicability of standards listed in Table 2 needs to be checked for powders, and material grade

selected.
It can be necessary to use multiple testing procedures in combination.
The values shall be expressed in weight percentage.
Analysis method(s) should be reported with results.
4.6 Characteristic densities

Apparent and tap densities are useful powder characteristics, enabling the control of different powder

lots, or different powder mixtures from virgin and used powders over time, respectively.

Apparent density shall be determined by Hall funnel method according to ISO 3923-1 or ASTM B212 for

free flowing powder. For non-free flowing powder, the Carney funnel method according to ISO 3923-1

or ASTM B417 shall be used; for powders that do not flow freely through a Carney funnel, a Scott

apparatus according to ISO 3923-2 or ASTM B329 shall be used.

To determine the appropriate size of graduated cylinder used in tap density measurement, apparent

density should be measured first. Tap density shall be measured according to ISO 3953 or ASTM B527.

NOTE 1 In practice, the minimum number of taps, N, is determined such that no further change in volume takes

place. For all further tests on the same type of powder, the cylinder is subjected to 2N taps, except where general

experience and acceptance has established a specific number of taps (no less than N taps) as being satisfactory.

For fine refractory metallic powders, 3 000 taps has been found to be satisfactory for all sizes.

Skeletal density by gas pycnometry can be determined according to ISO 12154 or ASTM B923. The

skeletal density gives the true density of the material and can therefore be used to evaluate porosity level.

NOTE 2 SEM images of the powder after a sample preparation can give qualitative information only about

internal porosity. For example, see EN 1274.
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4.7 Morphology

Powder morphology is strongly linked to the process used to produce the powder; as stated and

illustrated in EN 1274. Particle morphology shall be described using the vocabulary defined in ISO 3252

or ASTM B243 (see Annex A for examples).

NOTE 1 Powder morphology is considered to be a useful property for comparing and controlling different lots

of powders over time.

In addition, qualitative image comparison and/or quantitative criteria can be subjected to a prior

customer/supplier agreement e.g. a quantitative shape factor defined as the maximum Feret’s diameter

divided by minimum Feret’s diameter, etc.
NOTE 2 The preferred method using SEM is secondary electron imaging.

Quantitative values shall be determined by automatic or semi-automatic methods with the number of

analysed particles being included in the report.

NOTE 3 A standard method for spreadability is under development within ISO/TC 261 and ASTM F 42.

Information on spreadability can be found in ASTM D7891.
4.8 Flowability

Powder flowability is a function of multiple factors, particularly the following:

— powder size distribution,

— cohesive strength by adsorbed water on the particles' surfaces from condensed, i.e. presence of

agglomerating forces such as capillary bridges formed by adsorbed water on particles’ surfaces

from condensed atmospheric vapour, electromagnetic forces in ferromagnetic materials, or Van der

Waals bonds,

— inter-particles friction, affected mostly by particles "surface roughness" and morphology of the

particle surfaces.

As moisture content is a key factor in determining flowability, where drying is required or prohibited

by the customer/supplier agreement or the selected flowability standard method (see list below), this

shall be performed in accordance wi
...

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