EN ISO/ASTM 52940:2025

SLOVENSKI STANDARD
01-maj-2026
Dodajalna izdelava keramičnih izdelkov - Surovine - Karakterizacija keramične
suspenzije pri fotopolimerizaciji v posodi (ISO/ASTM 52940:2025)
Additive manufacturing of ceramics - Feedstock materials - Characterization of ceramic
slurry in vat photopolymerization (ISO/ASTM 52940:2025)
Additive Fertigung von Keramiken - Ausgangsmaterialien - Charakterisierung von
Keramikschlicker der Vat-Photopolymerisation (ISO/ASTM 52940:2025)
Fabrication additive de céramiques - Matières premières - Caractérisation de la
barbotine de céramique en photopolymérisation en cuve (ISO/ASTM 52940:2025)
Ta slovenski standard je istoveten z: EN ISO/ASTM 52940:2025
ICS:
25.030 3D-tiskanje Additive manufacturing
81.060.01 Keramika na splošno Ceramics in general
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO/ASTM 52940
EUROPEAN STANDARD
NORME EUROPÉENNE
November 2025
EUROPÄISCHE NORM
ICS 25.030
English Version
Additive manufacturing of ceramics - Feedstock materials -
Characterization of ceramic slurry in vat
photopolymerization (ISO/ASTM 52940:2025)
Fabrication additive de céramiques - Matières Additive Fertigung von Keramiken -
premières - Caractérisation de la barbotine de Ausgangsmaterialien - Charakterisierung von
céramique en photopolymérisation en cuve (ISO/ASTM Keramikschlicker der Vat-Photopolymerisation
52940:2025) (ISO/ASTM 52940:2025)
This European Standard was approved by CEN on 16 November 2025.

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, Türkiye 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
© 2025 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO/ASTM 52940:2025 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO/ASTM 52940:2025) 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 May 2026, and conflicting national standards shall be
withdrawn at the latest by May 2026.
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.
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 website.
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, Türkiye and the
United Kingdom.
Endorsement notice
The text of ISO/ASTM 52940:2025 has been approved by CEN as EN ISO/ASTM 52940:2025 without
any modification.
International
Standard
ISO/ASTM 52940
First edition
Additive manufacturing of
2025-11
ceramics — Feedstock materials —
Characterization of ceramic slurry
in vat photopolymerization
Fabrication additive de céramiques — Matières premières
— Caractérisation de la barbotine de céramique en
photopolymérisation en cuve
Reference number
ISO/ASTM 52940:2025(en) © ISO/ASTM International 2025

ISO/ASTM 52940:2025(en)
© ISO/ASTM International 2025
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
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Published in Switzerland
© ISO/ASTM International 2025 – All rights reserved
ii
ISO/ASTM 52940:2025(en)
Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Sampling and preparation of test sample . 2
5 Slurry characterization . 2
5.1 Ceramics content .2
5.2 Dynamic viscosity.2
5.3 Particle size distribution .3
5.4 Chemical composition of ceramic powders.4
5.5 Solid dispersion stability .5
6 Test report . 5
Annex A (informative) Principle of the ceramics content. 7
Annex B (informative) Characteristics and observation methods for changes in dispersion
stability . 8
Bibliography . 9

© ISO/ASTM International 2025 – All rights reserved
iii
ISO/ASTM 52940:2025(en)
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 261, Additive manufacturing, in cooperation
with ASTM Committee F42, 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, and in collaboration with the European Committee for Standardization (CEN)
Technical Committee CEN/TC 438, Additive manufacturing, in accordance with the Agreement on technical
cooperation between ISO and CEN (Vienna Agreement).
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.

© ISO/ASTM International 2025 – All rights reserved
iv
International Standard ISO/ASTM 52940:2025(en)
Additive manufacturing of ceramics — Feedstock materials —
Characterization of ceramic slurry in vat photopolymerization
1 Scope
This document specifies the characterization of ceramic slurry for use as feedstock in vat photopolymerization
additive manufacturing (AM) processes. The characterization includes the composition and properties of
the slurry, such as solids content, dynamic viscosity, particle size distribution, chemical composition, and
solid dispersion stability. This document also provides available methods on sampling and preparing slurry
samples for testing.
This document does not deal with safety aspects.
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 1513, Paints and varnishes — Examination and preparation of test samples
ISO 3252, Powder metallurgy — Vocabulary
ISO 8213, Chemical products for industrial use — Sampling techniques — Solid chemical products in the form of
particles varying from powders to coarse lumps
ISO 9276-1, Representation of results of particle size analysis — Part 1: Graphical representation
ISO 9276-2, Representation of results of particle size analysis — Part 2: Calculation of average particle sizes/
diameters and moments from particle size distributions
ISO 11358-1, Plastics — Thermogravimetry (TG) of polymers — Part 1: General principles
ISO 13097, Guidelines for the characterization of dispersion stability
ISO/ASTM 52900, Additive manufacturing — General principles — Fundamentals and vocabulary
ASTM B243, Standard Terminology of Powder Metallurgy
ASTM C242, Standard Terminology of Ceramic Whitewares and Related Products
ASTM C1145, Standard Terminology of Advanced Ceramics
ASTM D6370, Standard Test Method for Rubber — Compositional Analysis by Thermogravimetry (TGA)
ASTM D7348, Standard Test Methods for Loss on Ignition (LOI) of Solid Combustion Residues
ASTM E1131, Standard Test Method for Compositional Analysis by Thermogravimetry
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 3252, ISO/ASTM 52900, ASTM
B243, ASTM C242 and ASTM C1145 apply.

© ISO/ASTM International 2025 – All rights reserved
ISO/ASTM 52940:2025(en)
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
4 Sampling and preparation of test sample
Test samples shall be representatives of the ceramic slurry product batch. The sampling methods and
devices for a certain quantity of ceramic slurry shall comply with the requirements mutually agreed upon
by the supplier and customer. The obtained samples shall be suitable for examination and preparation in
accordance with ISO 1513. The sampling procedure for testing raw ceramic powders prior to mixing with
photocurable resins shall comply with the requirements specified in ISO 8213; otherwise, the methods
specified in a suitable national standard, or another method mutually agreed upon by the supplier and
customer, shall be used.
The number of samples to be taken depends on the sampling plan (e.g. ISO 28590) or supply agreements. Test
samples shall be taken in consideration of the minimum sample amount as well as the repetitions required
in each test method. Preparation of test samples as well as all operations for subsequent characterization
tests are recommended to be performed under a UV-blocked laboratory environment.
5 Slurry characterization
5.1 Ceramics content
Ceramics content refers to the amount of ceramic powder in the total slurry. The amount of ceramic powder
that has been added during the slurry preparation process is expressed as mass fraction in SI unit (kg/kg)
or more commonly mass percentage (wt %). If the proportion of ceramic powder in test sample is unknown,
the ceramics content shall be estimated from the loss on ignition of ceramic slurry referring to ISO 11358-1,
ASTM D6370, ASTM D7348, and ASTM E1131 (see Annex A).
5.2 Dynamic viscosity
Dynamic viscosity describes the flow resistance of a fluid and is an important fluid property that is related
2 -1 -1
to the internal friction within the fluid. Dynamic viscosity is usually expressed in N·s/m , kg·m ·s , Pa·s (or
mPa·s) in SI units, or P (or cP) in CGS units.
X = shear rate in 1/s X = shear rate in 1/s
Y = viscosity (Pa s) Y = viscosity (Pa s)
a) Zirconia slurry b) Alumina slurry

© ISO/ASTM International 2025 – All rights reserved
ISO/ASTM 52940:2025(en)
Figure 1 — Examples of dynamic viscosity of the commercial AM ceramic slurries
Dynamic viscosity is the measurement of a fluids resistance to gradual deformation or movement caused
by shear or tensile stress, and it usually refers to the rheological property of a suspension slurry in ceramic
materials. The dynamic viscosity of a ceramic slurry in vat photopolymerization is affected by various
factors, such as ceramic powder contents, particle distribution and shapes, the types of resins, hydrodynamic
interactions between powders and resins, and slurry mixing condit
...