EN ISO/ASTM 52924:2023

Additive manufacturing of polymers - Qualification principles - Classification of part properties (ISO/ASTM 52924:2023)

This document establishes the required or the achievable classes of part properties for additive manufactured polymer parts in order to get a common understanding on part quality. It is aimed at providers of manufacturing services for polymer parts who use additive manufacturing machines and at the customers for these services. Designers of parts as well as buyers and providers of manufacturing services can specify, in a traceable manner, the required or the achievable level of part properties with the aid of this document. The classification is based on mechanical, physical and geometrical properties. Further properties can be defined between buyer and provider of manufacturing.
This document is applicable to parts that have been manufactured from a thermoplastic polymer by means of thermal reaction fusion of material typically applied by a powder bed fusion (PBF) or material extrusion (MEX) processes. This document is also applicable to thermoplastic parts made by other processes, provided that due consideration is given to process-specific topics.
The classification of part properties applies to parts in as-built condition, that have been unpacked from the build space, with all support structures removed, but prior to any post-processing operations.
Specific industries (e.g. aerospace and medical) typically specify additional requirements.

Additive Fertigung von Polymeren - Qualifizierungsgrundsätze - Klassifizierung von Bauteileigenschaften (ISO/ASTM 52924:2023)

Dieses Dokument legt die erforderlichen oder die erreichbaren Bauteileigenschaftsklassen für additiv gefertigte Kunststoffbauteile fest, um ein allgemeines Verständnis über die Bauteilqualität zu ermöglichen. Es wendet sich an Anbieter von Fertigungsdienstleistungen für Kunststoffbauteile, die zur Herstellung additive Fertigungsanlagen einsetzen, und an die Auftraggeber dieser Dienstleistungen. Konstrukteure von Bauteilen sowie Einkäufer und Anbieter von Fertigungsdienstleistungen können das erforderliche beziehungsweise die erreichbaren Bauteileigenschaften mithilfe dieses Dokuments nachvollziehbar spezifizieren. Die Klassifizierung basiert auf mechanischen, physikalischen und geometrischen Eigenschaften. Zwischen dem Käufer und dem Fertigungsanbieter können weitere Eigenschaften festgelegt werden.
Dieses Dokument ist anwendbar für Bauteile, die mittels einer, typischerweise mithilfe von pulverbettbasierten Schmelzverfahren (PBF) oder Materialextrusionsverfahren (MEX) herbeigeführten, thermischen Reaktionsfusion eines Materials aus einem thermoplastischen Polymer gefertigt wurden. Dieses Dokument ist auch anwendbar für mittels anderer Prozesse gefertigte thermoplastische Bauteile, vorausgesetzt, dass die prozessspezifischen Themen berücksichtigt werden.
Die Klassifizierung der Bauteileigenschaften gilt für aus dem Bauraum entpackte Teile im Zustand „wie gebaut“, an denen sämtliche Stützkonstruktionen entfernt, jedoch noch keine Nachbearbeitungsarbeiten durchgeführt wurden.
Bestimmte Branchen (z. B. Luft- und Raumfahrt und Medizin) legen typischerweise zusätzliche Anforderungen fest.

Fabrication additive des polymères - Principes de qualification - Classification des propriétés de la pièce (ISO/ASTM 52924:2023)

Le présent document établit les classes de propriétés de la pièce requises ou pouvant être atteintes pour les pièces en polymère fabriquées de manière additive, afin de disposer d’une compréhension  commune sur la qualité des pièces. Il est destiné aux fournisseurs de services de fabrication de pièces en polymère qui utilisent des machines de fabrication additive et aux clients de ces services. Les concepteurs de pièces aussi bien que les acheteurs et les fournisseurs de services de fabrication peuvent spécifier, de manière traçable, le niveau des propriétés de la pièce requis ou pouvant être atteint à l’aide du présent document. La classification est basée sur des propriétés mécaniques, physiques et géométriques. D’autres propriétés peuvent être définies entre l’acheteur et le fournisseur de services de fabrication.
Le présent document s’applique aux pièces qui ont été fabriquées à partir d’un polymère thermoplastique par réaction thermique de fusion de matériau généralement réalisée par des procédés de fusion sur lit de poudre (PBF) ou d’extrusion de matériau (MEX).
La classification des propriétés de la pièce s’applique à des pièces en état de fabrication qui ont été déballées depuis l’espace de fabrication, avec l'ensemble des structures support ayant été retirées, mais avant toute opération de post-traitement.
Certaines industries (par exemple l'aérospatiale et le médical) spécifient généralement des exigences supplémentaires.

Dodajalna izdelava polimernih izdelkov - Kvalifikacija - Razvrščanje lastnosti polimernih izdelkov (ISO/ASTM 52924:2023)

Ta standard je namenjen ponudnikom proizvodnih storitev za polimerne dele, ki uporabljajo stroje za aditivno proizvodnjo, in strankam za te storitve. Projektanti delov ter kupci in ponudniki proizvodnih storitev lahko s pomočjo tega standarda na sledljiv način določijo zahtevano ali dosegljivo raven kakovosti. Ta standard se uporablja za dele, ki so bili proizvedeni iz termoplastičnega polimera z laserskim sintranjem (LS) ali iztiskanjem materiala (MEX). V konkretnem primeru je treba preveriti njegovo uporabnost za druge postopke za polimere. Razredi kakovosti se uporabljajo za dele, ki niso bili naknadno obdelani po razpakiranju iz delovnega prostora in odstranitvi morebitnih podpornih struktur.

General Information

• Status: Published
• Publication Date: 15-Aug-2023
• Withdrawal Date: 01-May-2022
• ICS: 25.030 - Additive manufacturing
• Technical Committee: CEN/TC 438 - Additive Manufacturing
• Drafting Committee: CEN/TC 438 - Additive Manufacturing
• Current Stage: 6060 - Definitive text made available (DAV) - Publishing
• Start Date: 16-Aug-2023
• Completion Date: 16-Aug-2023
• Ref Project: SIST EN ISO/ASTM 52924:2023 - Additive manufacturing of polymers - Qualification principles - Classification of part properties (ISO/ASTM 52924:2023)

Standards Content (Sample)

SLOVENSKI STANDARD
01-november-2023
Dodajalna izdelava polimernih izdelkov - Kvalifikacija - Razvrščanje lastnosti
polimernih izdelkov (ISO/ASTM 52924:2023)
Additive manufacturing of polymers - Qualification principles - Classification of part
properties (ISO/ASTM 52924:2023)
Additive Fertigung - Qualifizierungsgrundsätze - Güteklassen für additiv gefertigte
Kunststoffbauteile (ISO/ASTM 52924:2023)
Fabrication additive des polymères - Principes de qualification - Classification des
propriétés de la pièce (ISO/ASTM 52924:2023)
Ta slovenski standard je istoveten z: EN ISO/ASTM 52924:2023
ICS:
25.030 3D-tiskanje Additive manufacturing
83.080.01 Polimerni materiali na Plastics in general
splošno
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO/ASTM 52924
EUROPEAN STANDARD
NORME EUROPÉENNE
August 2023
EUROPÄISCHE NORM
ICS 25.030
English Version
Additive manufacturing of polymers - Qualification
principles - Classification of part properties (ISO/ASTM
52924:2023)
Fabrication additive des polymères - Principes de Additive Fertigung - Qualifizierungsgrundsätze -
qualification - Classification des propriétés de la pièce Güteklassen für additiv gefertigte Kunststoffbauteile
(ISO/ASTM 52924:2023) (ISO/ASTM 52924:2023)
This European Standard was approved by CEN on 16 July 2023.

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
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO/ASTM 52924:2023 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO/ASTM 52924:2023) 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 February 2024, and conflicting national standards
shall be withdrawn at the latest by February 2024.
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 52924:2023 has been approved by CEN as EN ISO/ASTM 52924:2023 without
any modification.
INTERNATIONAL ISO/ASTM
STANDARD 52924
First edition
2023-08
Additive manufacturing of
polymers — Qualification principles
— Classification of part properties
Fabrication additive des polymères — Principes de qualification —
Classification des propriétés de la pièce
Reference number
ISO/ASTM 52924:2023(E)
© ISO/ASTM International 2023
ISO/ASTM 52924:2023(E)
© ISO/ASTM International 2023
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: [phone] Phone: [phone]
Fax: [phone]
Email: [e-mail] Email: [e-mail]
Website: www.iso.org Website: www.astm.org
Published in Switzerland
ii
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3  Terms and definitions . 1
4 Symbols and abbreviations .2
4.1 Symbols . 2
4.2 Abbreviations . 2
5  Classification system . 3
5.1 Definition of the classes of part property . 3
5.2 Typical classification of important material classes and usage of the classification
system for part properties . 4
6  Test specimens for determining the characteristic values for the classification
system. 6
6.1 General . 6
6.2 Tensile properties . 6
6.3 Dimensional accuracy . 6
6.4 Density . 6
6.5 Labelling . 7
6.6 Orientation, grid arrangement, and distribution in the build space . 7
6.6.1 General . 7
6.6.2 Orientation and grid arrangement to be used . 7
6.6.3 Distribution in the build space . 7
6.7 Manufacturing . 11
7  Determination of characteristic values and classification in the classification
system.12
7.1 General .12
7.2 Mechanical properties . 12
7.2.1 General .12
7.2.2 Determination of characteristic values .12
7.2.3 Classification in the classification system .13
7.3 Dimensional accuracy .13
7.3.1 General .13
7.3.2 Determination of characteristic values . 13
7.3.3 Classification in the classification system . 14
7.4 Relative part density . 14
7.4.1 General . 14
7.4.2 Determination of characteristic values . 14
7.4.3 Classification in the classification system . 14
7.5 Classification in classes of part properties . 14
8  Initial classification and regular checking of the classifications .15
8.1 Standard classification procedure . 15
8.2 Initial classification . 15
8.3 Regular checking . 15
8.4 Renewed determination of the classifications in case of replacement of relevant
machine components . 15
Annex A (informative)  Form for part property classification in accordance with this
document .17
Bibliography .18
iii
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(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 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.
iv
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(E)
Introduction
The goal of this document is to improve the communication between providers and users of additive
manufactured polymer parts in relation to the part quality to be supplied. For this purpose, quality
criteria and part properties are categorised into a system of quality classes.
In the additive manufacturing processes relevant for polymers, the part properties depend very heavily
on the machine systems, the material and the process control used. Typically, the process control can
be optimised for productivity or quality. These goals are in principle contradictory in the context of the
performance of a specific machine.
The property classes listed in this document help to make clear the differences in quality. The property
classes enable the user to define part specifications for manufacturing.
Along with the specification of the property classes, this document states which property classes
can be achieved with typical materials. Test specimens and their arrangement in the build space are
specified (the related CAD data are included with this document as positioned STL data and AMF data
and available on: https://standards.iso.org/iso/52924/ed-1/en/). The determination of the mechanical
tensile properties, the dimensional accuracy and the part density with the aid of these test specimens
is described to make possible the assignment to property classes for the related characteristic values.
This document refers to parts produced by PBF and MEX processes. Certain processes within these
categories have also been known under different process names and trademarks. For example, (for
PBF) laser sintering when the fusion is enabled by a laser, -trademarked as SLS®, (selective laser
1)
sintering) . Other thermoplastic PBF trademarks include multi jet fusion (MJF) or high speed sintering
where the fusion is enabled by infra-red light. MEX processes for thermoplastic polymers are also
known by names such as fused layer modelling (FLM), fused layer manufacturing or fused filament
fabrication (FFF). FDM (fused deposition modelling) is an existing trademark for this type of process.
The mentioning of trademarks in this document are only for informative reasons and does not intend
any form of endorsement of the mentioned products.
Rather than comparing capabilities of hardware, material solutions based on common parameter
set inputs, are compared based on part property outcomes. This document supplies a framework for
comparison of those outcomes. The goal of such a comparison exercise is one of “what does it take to
get to a particular class outcome". The benefit of this approach is to decouple the nuances of different
hardware solution providers from the comparison process, allowing a focus on material property
outcomes, which are much more impactful in terms of end user value.
1)  SLS® is an example of a suitable product available commercially. This information is given for the convenience
of users of this document and does not constitute an endorsement by ISO of this product.
v
© ISO/ASTM International 2023 – All rights reserved

INTERNATIONAL STANDARD ISO/ASTM 52924:2023(E)
Additive manufacturing of polymers — Qualification
principles — Classification of part properties
1 Scope
This document establishes the required or the achievable classes of part properties for additive
manufactured polymer parts in order to get a common understanding on part quality. It is aimed at
providers of manufacturing services for polymer parts who use additive manufacturing machines and
at the customers for these services. Designers of parts as well as buyers and providers of manufacturing
services can specify, in a traceable manner, the required or the achievable level of part properties with
the aid of this document. The classification is based on mechanical, physical and geometrical properties.
Further properties can be defined between buyer and provider of manufacturing.
This document is applicable to parts that have been manufactured from a thermoplastic polymer by
means of thermal reaction fusion of material typically applied by a powder bed fusion (PBF) or material
extrusion (MEX) processes. This document is also applicable to thermoplastic parts made by other
processes, provided that due consideration is given to process-specific topics.
The classification of part properties applies to parts in as-built condition, that have been unpacked
from the build space, with all support structures removed, but prior to any post-processing operations.
Specific industries (e.g. aerospace and medical) typically specify additional requirements.
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 37, Rubber, vulcanized or thermoplastic — Determination of tensile stress-strain properties
ISO 291, Plastics — Standard atmospheres for conditioning and testing
ISO 527-1, Plastics — Determination of tensile properties — Part 1: General principles
ISO 527-2, Plastics — Determination of tensile properties — Part 2: Test conditions for moulding and
extrusion plastics
ISO 10350-1, Plastics — Acquisition and presentation of comparable single-point data — Part 1: Moulding
materials
2)
ISO 17295 , Additive manufacturing — General principles — Part positioning, coordinates and orientation
ISO/ASTM 52900, Additive manufacturing — General principles — Fundamentals and vocabulary
3  Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/ASTM 52900 and the
following apply.
2)  ISO 17295 cancels and replaces ISO/ASTM 52921-13 which is still available at
https:// www .astm .org/ f2921 -13r19 .html.
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(E)
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/
3.1
part density
ρ
density of a part in as-built condition
Note 1 to entry: The part density is calculated by the following formula:
m
ρ= (1)
V
where m is the mass of the sample and V is the nominal volume according to the external dimensions of
the sample.
3.2
nominal material density
ρ
M
solid density of the part material, measured on a specimen free of pores
Note 1 to entry: In data sheets, the nominal material density is mostly stated as material density of compounded,
injection molded or compression molded material.
3.3
relative part density
D
ratio of part density (3.1), and nominal material density ρ (3.2)
M
Note 1 to entry: The relative part density is calculated by:
ρ
D= (2)
ρ
M
4 Symbols and abbreviations
4.1 Symbols
The following symbols are used throughout this document:
Symbol Designation Unit
D relative part density %
m part mass g, kg
V part volume cm
ρ part density g/cm
Ρ nominal material density g/cm
M
4.2 Abbreviations
The following abbreviations are used throughout this document:
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(E)
ABS acrylonitrile butadiene styrene
MEX material extrusion
NW non-tool related dimensions
PA6 polyamide 6
PA11 polyamide 11
PA12 polyamide 12
PAEK polyaryletherketone
PC polycarbonate
PE polyethylene
PEI/PC polyetherimide/polycarbonate blend
PP polypropylene
TG tolerance group
TPE thermoplastic elastomer
TPA thermoplastic copolyamide
TPC thermoplastic polyester elastomer
TPU thermoplastic polyurethane
5  Classification system
5.1  Definition of the classes of part property
Classes of part properties shall be established based on mechanical tensile properties, density and
dimensional accuracy of manufactured parts.
To make the differences in quality during the additive manufacturing of polymer parts clearer and
easier to communicate, the classification system shown in Table 1 shall be used.
This system classifies typical value ranges for important part characteristics and assigns these ranges
to common materials for the powder bed fusion and material extrusion processes.
The classification system contains eleven different classes of part properties that are sequentially
numbered from 0 to 10.
Material characteristic values determined as per typical standards from the tensile test (ISO 527-1 or
for elastic materials ISO 37) and the density measurement in 7.4 are used as characteristic values. At
the same time, the dimensional accuracy achievable with additive manufacturing is assigned to the
tolerance classes in accordance with ISO 20457 for dimensions that are not tool related.
Part property classes 0 to 10 cover ranges that can typically be achieved on consideration of all the
material aspects of polymer-processing additive processes. Here each characteristic value shall be
considered independent from the others and dependent on the part orientation. This means that each
characteristic value can have a different class.
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(E)
Table 1 — Classes of part properties for polymer parts from additive manufacturing
Characteristic Tensile modulus Strength/ tensile Strain at break/  Relative part Dimensional
value strength elongation at density accuracy
break
Unit MPa MPa % %
Test standard ISO 527-1 ISO 527-1/ ISO 37 ISO 527-1/ ISO 37 In accordance ISO 20457
with 7.4
Class 10 >8 000 >100 >200 >99,5 —
Class 9 >6 000 ≤ 8 000 >85 ≤ 100 >100 ≤ 200 >99 ≤ 99,5 —
Class 8 >5 000 ≤ 6 000 >70 ≤ 85 >50 ≤ 100 >98,5 ≤ 99 TG 1 NW
Class 7 >4 000 ≤ 5 000 >60 ≤ 70 >35 ≤ 50 >97,5 ≤ 98,5 TG 2 NW
Class 6 >3 000 ≤ 4 000 >50 ≤ 60 >25 ≤ 35 >95 ≤ 97,5 TG 3 NW
Pro-per-
Class 5 >2 500 ≤ 3 000 >45 ≤ 50 >20 ≤ 25 >92,5 ≤ 95 TG 4 NW
ty class
Class 4 >2 000 ≤ 2 500 >40 ≤ 45 >15 ≤ 20 >90 ≤ 92,5 TG 5 NW
Class 3 >1 500 ≤ 2 000 >30 ≤ 40 >10 ≤ 15 >85 ≤ 90 TG 6 NW
Class 2 >1 000 ≤ 1 500 >20 ≤ 30 >5 ≤ 10 >80 ≤ 85 TG 7 NW
Class 1 >500 ≤ 1 000 >10 ≤ 20 >3 ≤ 5 >70 ≤ 80 TG 8 NW
Class 0 >0 ≤ 500 >0 ≤ 10 > 0 ≤ 3 >0 ≤ 70 TG 9
5.2  Typical classification of important material classes and usage of the classification
system for part properties
The intention is to make the range of typical part properties for a material type and an additive
manufacturing process distinguishable and comparable. To clarify this point, typical average
classifications for important material classes for powder bed fusion and for material extrusion are
summarised in Table 2 based on the state of the art and experts’ experience.
The compilation shows that characteristic values cannot always be classified exactly in one grade. Due
to differences between machines and variations in parameters, the related achievable characteristic
values can fall into different classes. On the basis of Table 2, users of additive manufactured parts can
compare the quality of parts from different providers, different machines and parameter sets by asking
the part manufacturers on their classifications. The actual requirements on the specific parts can then
be defined depending on the intended application of the final part using the classification system.
Table 2 — Examples for classifications for typical powder bed fusion and material extrusion
materials
Characteristic PA 11 PAEK TPA/TPC/ PEI/PC PA 12
Class PA 12 (PBF) ABS (MEX)
value range (PBF) (PBF) TPU (PBF) (MEX) (MEX)
XY/ XY/ XY/ XY/ XY/ XY/
Alignment XY/YX ZX ZX ZX ZX ZX ZX ZX
YX YX YX YX YX YX
<500 0   X X
500 ≤ 1 000 1
1 000 ≤ 1 500 2      X X
1 500 ≤ 2 000 3 X X X X    X X
2 000 ≤ 2 500 4    X X X
2 500 ≤ 3 000 5     X
3 000 ≤ 4 000 6  X X
4 000 ≤ 5 000 7
5 000 ≤ 6 000 8
6 000 ≤ 8 000 9
>8 000 10
a
The component density is specified independent of orientation.
© ISO/ASTM International 2023 – All rights reserved

C
...

SLOVENSKI STANDARD
01-november-2023
Aditivna proizvodnja polimernih izdelkov - Kvalifikacija - Razvrščanje lastnosti
polimernih izdelkov (ISO/ASTM 52924:2023)
Additive manufacturing of polymers - Qualification principles - Classification of part
properties (ISO/ASTM 52924:2023)
Additive Fertigung - Qualifizierungsgrundsätze - Güteklassen für additiv gefertigte
Kunststoffbauteile (ISO/ASTM 52924:2023)
Fabrication additive des polymères - Principes de qualification - Classification des
propriétés de la pièce (ISO/ASTM 52924:2023)
Ta slovenski standard je istoveten z: EN ISO/ASTM 52924:2023
ICS:
25.030 3D-tiskanje Additive manufacturing
83.080.01 Polimerni materiali na Plastics in general
splošno
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO/ASTM 52924
EUROPEAN STANDARD
NORME EUROPÉENNE
August 2023
EUROPÄISCHE NORM
ICS 25.030
English Version
Additive manufacturing of polymers - Qualification
principles - Classification of part properties (ISO/ASTM
52924:2023)
Fabrication additive des polymères - Principes de Additive Fertigung - Qualifizierungsgrundsätze -
qualification - Classification des propriétés de la pièce Güteklassen für additiv gefertigte Kunststoffbauteile
(ISO/ASTM 52924:2023) (ISO/ASTM 52924:2023)
This European Standard was approved by CEN on 16 July 2023.

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
© 2023 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO/ASTM 52924:2023 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO/ASTM 52924:2023) 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 February 2024, and conflicting national standards
shall be withdrawn at the latest by February 2024.
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 52924:2023 has been approved by CEN as EN ISO/ASTM 52924:2023 without
any modification.
INTERNATIONAL ISO/ASTM
STANDARD 52924
First edition
2023-08
Additive manufacturing of
polymers — Qualification principles
— Classification of part properties
Fabrication additive des polymères — Principes de qualification —
Classification des propriétés de la pièce
Reference number
ISO/ASTM 52924:2023(E)
© ISO/ASTM International 2023
ISO/ASTM 52924:2023(E)
© ISO/ASTM International 2023
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: [phone] Phone: [phone]
Fax: [phone]
Email: [e-mail] Email: [e-mail]
Website: www.iso.org Website: www.astm.org
Published in Switzerland
ii
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3  Terms and definitions . 1
4 Symbols and abbreviations .2
4.1 Symbols . 2
4.2 Abbreviations . 2
5  Classification system . 3
5.1 Definition of the classes of part property . 3
5.2 Typical classification of important material classes and usage of the classification
system for part properties . 4
6  Test specimens for determining the characteristic values for the classification
system. 6
6.1 General . 6
6.2 Tensile properties . 6
6.3 Dimensional accuracy . 6
6.4 Density . 6
6.5 Labelling . 7
6.6 Orientation, grid arrangement, and distribution in the build space . 7
6.6.1 General . 7
6.6.2 Orientation and grid arrangement to be used . 7
6.6.3 Distribution in the build space . 7
6.7 Manufacturing . 11
7  Determination of characteristic values and classification in the classification
system.12
7.1 General .12
7.2 Mechanical properties . 12
7.2.1 General .12
7.2.2 Determination of characteristic values .12
7.2.3 Classification in the classification system .13
7.3 Dimensional accuracy .13
7.3.1 General .13
7.3.2 Determination of characteristic values . 13
7.3.3 Classification in the classification system . 14
7.4 Relative part density . 14
7.4.1 General . 14
7.4.2 Determination of characteristic values . 14
7.4.3 Classification in the classification system . 14
7.5 Classification in classes of part properties . 14
8  Initial classification and regular checking of the classifications .15
8.1 Standard classification procedure . 15
8.2 Initial classification . 15
8.3 Regular checking . 15
8.4 Renewed determination of the classifications in case of replacement of relevant
machine components . 15
Annex A (informative)  Form for part property classification in accordance with this
document .17
Bibliography .18
iii
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(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 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.
iv
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(E)
Introduction
The goal of this document is to improve the communication between providers and users of additive
manufactured polymer parts in relation to the part quality to be supplied. For this purpose, quality
criteria and part properties are categorised into a system of quality classes.
In the additive manufacturing processes relevant for polymers, the part properties depend very heavily
on the machine systems, the material and the process control used. Typically, the process control can
be optimised for productivity or quality. These goals are in principle contradictory in the context of the
performance of a specific machine.
The property classes listed in this document help to make clear the differences in quality. The property
classes enable the user to define part specifications for manufacturing.
Along with the specification of the property classes, this document states which property classes
can be achieved with typical materials. Test specimens and their arrangement in the build space are
specified (the related CAD data are included with this document as positioned STL data and AMF data
and available on: https://standards.iso.org/iso/52924/ed-1/en/). The determination of the mechanical
tensile properties, the dimensional accuracy and the part density with the aid of these test specimens
is described to make possible the assignment to property classes for the related characteristic values.
This document refers to parts produced by PBF and MEX processes. Certain processes within these
categories have also been known under different process names and trademarks. For example, (for
PBF) laser sintering when the fusion is enabled by a laser, -trademarked as SLS®, (selective laser
1)
sintering) . Other thermoplastic PBF trademarks include multi jet fusion (MJF) or high speed sintering
where the fusion is enabled by infra-red light. MEX processes for thermoplastic polymers are also
known by names such as fused layer modelling (FLM), fused layer manufacturing or fused filament
fabrication (FFF). FDM (fused deposition modelling) is an existing trademark for this type of process.
The mentioning of trademarks in this document are only for informative reasons and does not intend
any form of endorsement of the mentioned products.
Rather than comparing capabilities of hardware, material solutions based on common parameter
set inputs, are compared based on part property outcomes. This document supplies a framework for
comparison of those outcomes. The goal of such a comparison exercise is one of “what does it take to
get to a particular class outcome". The benefit of this approach is to decouple the nuances of different
hardware solution providers from the comparison process, allowing a focus on material property
outcomes, which are much more impactful in terms of end user value.
1)  SLS® is an example of a suitable product available commercially. This information is given for the convenience
of users of this document and does not constitute an endorsement by ISO of this product.
v
© ISO/ASTM International 2023 – All rights reserved

INTERNATIONAL STANDARD ISO/ASTM 52924:2023(E)
Additive manufacturing of polymers — Qualification
principles — Classification of part properties
1 Scope
This document establishes the required or the achievable classes of part properties for additive
manufactured polymer parts in order to get a common understanding on part quality. It is aimed at
providers of manufacturing services for polymer parts who use additive manufacturing machines and
at the customers for these services. Designers of parts as well as buyers and providers of manufacturing
services can specify, in a traceable manner, the required or the achievable level of part properties with
the aid of this document. The classification is based on mechanical, physical and geometrical properties.
Further properties can be defined between buyer and provider of manufacturing.
This document is applicable to parts that have been manufactured from a thermoplastic polymer by
means of thermal reaction fusion of material typically applied by a powder bed fusion (PBF) or material
extrusion (MEX) processes. This document is also applicable to thermoplastic parts made by other
processes, provided that due consideration is given to process-specific topics.
The classification of part properties applies to parts in as-built condition, that have been unpacked
from the build space, with all support structures removed, but prior to any post-processing operations.
Specific industries (e.g. aerospace and medical) typically specify additional requirements.
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 37, Rubber, vulcanized or thermoplastic — Determination of tensile stress-strain properties
ISO 291, Plastics — Standard atmospheres for conditioning and testing
ISO 527-1, Plastics — Determination of tensile properties — Part 1: General principles
ISO 527-2, Plastics — Determination of tensile properties — Part 2: Test conditions for moulding and
extrusion plastics
ISO 10350-1, Plastics — Acquisition and presentation of comparable single-point data — Part 1: Moulding
materials
2)
ISO 17295 , Additive manufacturing — General principles — Part positioning, coordinates and orientation
ISO/ASTM 52900, Additive manufacturing — General principles — Fundamentals and vocabulary
3  Terms and definitions
For the purposes of this document, the terms and definitions given in ISO/ASTM 52900 and the
following apply.
2)  ISO 17295 cancels and replaces ISO/ASTM 52921-13 which is still available at
https:// www .astm .org/ f2921 -13r19 .html.
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(E)
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/
3.1
part density
ρ
density of a part in as-built condition
Note 1 to entry: The part density is calculated by the following formula:
m
ρ= (1)
V
where m is the mass of the sample and V is the nominal volume according to the external dimensions of
the sample.
3.2
nominal material density
ρ
M
solid density of the part material, measured on a specimen free of pores
Note 1 to entry: In data sheets, the nominal material density is mostly stated as material density of compounded,
injection molded or compression molded material.
3.3
relative part density
D
ratio of part density (3.1), and nominal material density ρ (3.2)
M
Note 1 to entry: The relative part density is calculated by:
ρ
D= (2)
ρ
M
4 Symbols and abbreviations
4.1 Symbols
The following symbols are used throughout this document:
Symbol Designation Unit
D relative part density %
m part mass g, kg
V part volume cm
ρ part density g/cm
Ρ nominal material density g/cm
M
4.2 Abbreviations
The following abbreviations are used throughout this document:
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(E)
ABS acrylonitrile butadiene styrene
MEX material extrusion
NW non-tool related dimensions
PA6 polyamide 6
PA11 polyamide 11
PA12 polyamide 12
PAEK polyaryletherketone
PC polycarbonate
PE polyethylene
PEI/PC polyetherimide/polycarbonate blend
PP polypropylene
TG tolerance group
TPE thermoplastic elastomer
TPA thermoplastic copolyamide
TPC thermoplastic polyester elastomer
TPU thermoplastic polyurethane
5  Classification system
5.1  Definition of the classes of part property
Classes of part properties shall be established based on mechanical tensile properties, density and
dimensional accuracy of manufactured parts.
To make the differences in quality during the additive manufacturing of polymer parts clearer and
easier to communicate, the classification system shown in Table 1 shall be used.
This system classifies typical value ranges for important part characteristics and assigns these ranges
to common materials for the powder bed fusion and material extrusion processes.
The classification system contains eleven different classes of part properties that are sequentially
numbered from 0 to 10.
Material characteristic values determined as per typical standards from the tensile test (ISO 527-1 or
for elastic materials ISO 37) and the density measurement in 7.4 are used as characteristic values. At
the same time, the dimensional accuracy achievable with additive manufacturing is assigned to the
tolerance classes in accordance with ISO 20457 for dimensions that are not tool related.
Part property classes 0 to 10 cover ranges that can typically be achieved on consideration of all the
material aspects of polymer-processing additive processes. Here each characteristic value shall be
considered independent from the others and dependent on the part orientation. This means that each
characteristic value can have a different class.
© ISO/ASTM International 2023 – All rights reserved

ISO/ASTM 52924:2023(E)
Table 1 — Classes of part properties for polymer parts from additive manufacturing
Characteristic Tensile modulus Strength/ tensile Strain at break/  Relative part Dimensional
value strength elongation at density accuracy
break
Unit MPa MPa % %
Test standard ISO 527-1 ISO 527-1/ ISO 37 ISO 527-1/ ISO 37 In accordance ISO 20457
with 7.4
Class 10 >8 000 >100 >200 >99,5 —
Class 9 >6 000 ≤ 8 000 >85 ≤ 100 >100 ≤ 200 >99 ≤ 99,5 —
Class 8 >5 000 ≤ 6 000 >70 ≤ 85 >50 ≤ 100 >98,5 ≤ 99 TG 1 NW
Class 7 >4 000 ≤ 5 000 >60 ≤ 70 >35 ≤ 50 >97,5 ≤ 98,5 TG 2 NW
Class 6 >3 000 ≤ 4 000 >50 ≤ 60 >25 ≤ 35 >95 ≤ 97,5 TG 3 NW
Pro-per-
Class 5 >2 500 ≤ 3 000 >45 ≤ 50 >20 ≤ 25 >92,5 ≤ 95 TG 4 NW
ty class
Class 4 >2 000 ≤ 2 500 >40 ≤ 45 >15 ≤ 20 >90 ≤ 92,5 TG 5 NW
Class 3 >1 500 ≤ 2 000 >30 ≤ 40 >10 ≤ 15 >85 ≤ 90 TG 6 NW
Class 2 >1 000 ≤ 1 500 >20 ≤ 30 >5 ≤ 10 >80 ≤ 85 TG 7 NW
Class 1 >500 ≤ 1 000 >10 ≤ 20 >3 ≤ 5 >70 ≤ 80 TG 8 NW
Class 0 >0 ≤ 500 >0 ≤ 10 > 0 ≤ 3 >0 ≤ 70 TG 9
5.2  Typical classification of important material classes and usage of the classification
system for part properties
The intention is to make the range of typical part properties for a material type and an additive
manufacturing process distinguishable and comparable. To clarify this point, typical average
classifications for important material classes for powder bed fusion and for material extrusion are
summarised in Table 2 based on the state of the art and experts’ experience.
The compilation shows that characteristic values cannot always be classified exactly in one grade. Due
to differences between machines and variations in parameters, the related achievable characteristic
values can fall into different classes. On the basis of Table 2, users of additive manufactured parts can
compare the quality of parts from different providers, different machines and parameter sets by asking
the part manufacturers on their classifications. The actual requirements on the specific parts can then
be defined depending on the intended application of the final part using the classification system.
Table 2 — Examples for classifications for typical powder bed fusion and material extrusion
materials
Characteristic PA 11 PAEK TPA/TPC/ PEI/PC PA 12
Class PA 12 (PBF) ABS (MEX)
value range (PBF) (PBF) TPU (PBF) (MEX) (MEX)
XY/ XY/ XY/ XY/ XY/ XY/
Alignment XY/YX ZX ZX ZX ZX ZX ZX ZX
YX YX YX YX YX YX
<500 0   X X
500 ≤ 1 000 1
1 000 ≤ 1 500 2      X X
1 500 ≤ 2 000 3 X X X X    X X
2 000 ≤ 2 500 4    X X X
2 500 ≤ 3 000 5     X
3 000 ≤ 4 000 6  X X
4 000 ≤ 5 000 7
5 000 ≤ 6 000 8
6 000 ≤ 8 000 9
>8 000 10
a
The component density is specified independent of orientation.
© ISO/ASTM International 2023 – All rights reserved
...