EN ISO 683-3:2019

Heat-treatable steels, alloy steels and free-cutting steels - Part 3: Case-hardening steels (ISO 683-3:2019)

This document specifies the technical delivery requirements for
—          semi-finished products, hot formed, e.g. blooms, billets, slabs (see NOTE 1),
—          bars (see NOTE 1),
—          wire rod,
—          finished flat products, and
—          hammer or drop forgings (see NOTE 1)
manufactured from the case-hardening non-alloy or alloy steels listed in Table 3 and supplied in one of the heat-treatment conditions given for the different types of products in Table 1 and in one of the surface conditions given in Table 2.
The steels are, in general, intended for the manufacture of case-hardened machine parts.
NOTE 1    Hammer-forged semi-finished products (blooms, billets, slabs, etc.), seamless rolled rings and hammer-forged bars are covered under semi-finished products or bars and not under the term "hammer and drop forgings".
NOTE 2    For International Standards relating to steels complying with the requirements for the chemical composition in Table 3, however, supplied in other product forms or treatment conditions than given above or intended for special applications, and for other related International Standards, see the Bibliography.
In special cases, variations in these technical delivery requirements or additions to them can form the subject of an agreement at the time of enquiry and order (see 5.2 and Annex A).
In addition to this document, the general technical delivery requirements of ISO 404 are applicable.

Für eine Wärmebehandlung bestimmte Stähle, legierte Stähle und Automatenstähle - Teil 3: Einsatzstähle (ISO 683-3:2019)

Aciers pour traitement thermique, aciers alliés et aciers pour décolletage - Partie 3: Aciers pour cémentation (ISO 683-3:2019)

Le présent document spécifie les conditions techniques de livraison des
—          demi-produits formés à chaud, comme par exemple les blooms, billettes et brames (voir NOTE 1);
—          barres (voir NOTE 1);
—          fils machine;
—          produits plats finis; et
—          pièces forgées par martelage ou estampage (voir NOTE 1)
fabriqués à partir d'aciers alliés ou non alliés pour cémentation énumérés dans le Tableau 3 et livrés dans l'un des états de traitement thermique donnés pour les différents types de produits dans le Tableau 1 et dans l'un des états de surface donnés dans le Tableau 2.
Les aciers sont en général destinés à la fabrication de pièces mécaniques cémentées.
NOTE 1    Les produits semi-finis forgés par martelage (blooms, billettes, brames, etc.), les anneaux laminés sans soudure et les barres forgées par martelage figurent parmi les produits semi-finis ou les barres, et non sous l'appellation «pièces forgées par martelage ou estampage».
NOTE 2    Pour les Normes internationales relatives aux aciers qui sont conformes aux exigences de composition chimique du Tableau 3, mais fournis sous d'autres formes de produits ou dans des états de traitement autres que ceux indiqués ci-dessus, ou qui sont destinés à des applications spéciales, ainsi que pour d'autres Normes internationales analogues, voir la Bibliographie.
Dans certains cas particuliers, il est possible de déroger aux présentes conditions techniques de livraison ou d'en ajouter d'autres, à condition d'en convenir au moment de l'appel d'offres et de la commande (voir 5.2 et Annexe A).
En complément du présent document, les conditions générales techniques de livraison de l'ISO 404 sont applicables.

Toplotno obdelana, legirana in avtomatna jekla - 3. del: Cementacijska jekla (ISO 683-3:2019)

Ta dokument določa tehnične dobavne zahteve za:
– vroče oblikovane polizdelke, npr. bloke, palice, plošče (glej OPOMBO 1),
– palice (glej OPOMBO 1),
– valjane žice,
– končne ploščate izdelke in
– izkovke, kovane s padalnimi kladivi (glej OPOMBO 1),
izdelane iz nelegiranih ali legiranih cementacijskih jekel, navedenih v preglednici 3, ter dobavljenih v enem od
stanj toplotne obdelave, podanih za različne vrste izdelkov v preglednici 1, in enem od
površinskih stanj, podanih v preglednici 2.
Jekla so na splošno namenjena za izdelavo cementiranih strojnih delov.
OPOMBA 1: S kladivom kovani polizdelki (bloki, palice, plošče itd.), nevarjeni valjani obročki in
s kladivom kovani drogovi so v nadaljevanju zajeti pod polizdelki ali drogovi in ne pod izrazom »izkovki, kovani
s padalnimi kladivi«.
OPOMBA 2: Za mednarodne standarde v zvezi z jekli, skladnimi z zahtevami za kemično
sestavo v preglednici 3, ki pa so dobavljena v drugih oblikah izdelkov ali stanjih obdelave, kot so podani zgoraj, ali
namenjena za posebne aplikacije, in za druge povezane mednarodne standarde glejte bibliografijo.
V posebnih primerih so lahko različice teh splošnih tehničnih dobavnih zahtev ali dodatki k njim
predmet sporazuma v času povpraševanja in naročila (glej točko 5.2 in dodatek A).
Poleg tega dokumenta se uporabljajo tudi zahteve splošnih dobavnih pogojev iz standarda ISO 404.

General Information

• Status: Withdrawn
• Publication Date: 12-Feb-2019
• Withdrawal Date: 13-Apr-2025
• ICS: 77.140.10 - Heat-treatable steels
• ICS: 77.140.20 - Stainless steels
• Technical Committee: ECISS/TC 105 - Steels for heat treatment, alloy steels, free-cutting steels and stainless steels
• Drafting Committee: ECISS/TC 105 - Steels for heat treatment, alloy steels, free-cutting steels and stainless steels
• Current Stage: 9960 - Withdrawal effective - Withdrawal
• Start Date: 09-Feb-2022
• Completion Date: 14-Apr-2025
• Ref Project: SIST EN ISO 683-3:2019 - Heat-treatable steels, alloy steels and free-cutting steels - Part 3: Case-hardening steels (ISO 683-3:2019)

Relations

• Replaces: EN ISO 683-3:2018 - Heat-treatable steels, alloy steels and free-cutting steels - Part 3: Case-hardening steels (ISO 683-3:2016)
• Effective Date: 01-Aug-2018
• Replaced By: EN ISO 683-3:2022 - Heat-treatable steels, alloy steels and free-cutting steels - Part 3: Case-hardening steels (ISO 683-3:2022)
• Effective Date: 01-May-2019

Standards Content (Sample)

SLOVENSKI STANDARD
01-april-2019
1DGRPHãþD
SIST EN ISO 683-3:2018
Toplotno obdelana, legirana in avtomatna jekla - 3. del: Cementacijska jekla (ISO
683-3:2019)
Heat-treatable steels, alloy steels and free-cutting steels - Part 3: Case-hardening steels
(ISO 683-3:2019)
Aciers pour traitement thermique, aciers alliés et aciers pour décolletage - Partie 3:
Aciers pour cémentation (ISO 683-3:2019)
Ta slovenski standard je istoveten z: EN ISO 683-3:2019
ICS:
77.140.10 Jekla za toplotno obdelavo Heat-treatable steels
77.140.20 Visokokakovostna jekla Stainless steels
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EN ISO 683-3
EUROPEAN STANDARD
NORME EUROPÉENNE
February 2019
EUROPÄISCHE NORM
ICS 77.140.10; 77.140.20 Supersedes EN ISO 683-3:2018
English Version
Heat-treatable steels, alloy steels and free-cutting steels -
Part 3: Case-hardening steels (ISO 683-3:2019)
Aciers pour traitement thermique, aciers alliés et Für eine Wärmebehandlung bestimmte Stähle, legierte
aciers pour décolletage - Partie 3: Aciers pour Stähle und Automatenstähle - Teil 3: Einsatzstähle (ISO
cémentation (ISO 683-3:2019) 683-3:2019)
This European Standard was approved by CEN on 17 December 2018.

CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 683-3:2019 E
worldwide for CEN national Members.

Contents Page
European foreword . 3

European foreword
This document (EN ISO 683-3:2019) has been prepared by Technical Committee ISO/TC 17 "Steel" in
collaboration with Technical Committee CEN/TC 459/SC 5 “Steels for heat treatment, alloy steels, free-
cutting steels and stainless steels” the secretariat of which is held by DIN.
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 August 2019, and conflicting national standards shall
be withdrawn at the latest by August 2019.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 683-3:2018.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta,
Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 683-3:2019 has been approved by CEN as EN ISO 683-3:2019 without any modification.
The European steel numbers to the steel grades are to be found in informative Annex B.
The references to following European standards are given for information:
EN 10017, Steels rod for drawing and/or cold rolling – Dimensions and tolerances
EN 10021, General technical delivery conditions for steel products
EN 10029, Hot-rolled steel plates 3 mm thick or above – Tolerances on dimensions and shape
EN 10048, Hot-rolled narrow steel strip – Tolerances on dimensions and shape
EN 10051, Continuously hot-rolled strip and plate/sheet cut from wide strip of non.-alloy and alloy steels –
Tolerances on dimensions and shape
EN 10058, Hot rolled flat steel bars and steel wide flats for general purposes – Dimensions and tolerances
on shape and dimensions
EN 10059, Hot rolled square steel bars for general purposes – Dimensions and tolerances on shape and
dimensions
EN 10060, Hot rolled round steel bars - Dimensions and tolerances on shape and dimensions
EN 10061, Hot rolled hexagon steel bars – Dimensions and tolerances on shape and dimensions
EN 10160, Ultrasonic testing of steel flat product of thickness equal to or greater than 6 mm (reflection
method)
EN 10204, Metallic products – Types of inspection documents
EN 10308, Non-destructive testing – Ultrasonic testing of steel bars
INTERNATIONAL ISO
STANDARD 683-3
Third edition
2019-01
Heat-treatable steels, alloy steels and
free-cutting steels —
Part 3:
Case-hardening steels
Aciers pour traitement thermique, aciers alliés et aciers pour
décolletage —
Partie 3: Aciers pour cémentation
Reference number
ISO 683-3:2019(E)
©
ISO 2019
ISO 683-3:2019(E)
© ISO 2019
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
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.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Fax: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved

ISO 683-3:2019(E)
Contents Page
Foreword .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 Classification and designation . 3
4.1 Classification . 3
4.2 Designation . 3
5 Information to be supplied by the purchaser. 3
5.1 Mandatory information . 3
5.2 Options and/or supplementary or special requirements . 3
5.3 Ordering example . 4
6 Manufacturing process . 4
6.1 General . 4
6.2 Deoxidation . 4
6.3 Heat-treatment condition and surface condition at delivery . 4
6.3.1 Normal condition at delivery . 4
6.3.2 Particular heat-treatment condition . . 4
6.3.3 Particular surface conditions . 4
6.4 Traceability of the cast . 4
7 Requirements . 5
7.1 Chemical composition, hardness and hardenability . 5
7.1.1 General. 5
7.1.2 Hardenability . 5
7.1.3 Chemical composition . 5
7.2 Machinability . 5
7.3 Cold shearability . 5
7.4 Grain size . 5
7.5 Non-metallic inclusions . 6
7.5.1 Microscopic inclusions . 6
7.5.2 Macroscopic inclusions . 6
7.6 Internal soundness . 6
7.7 Surface condition . 6
7.8 Shape, dimensions and tolerances . 6
8 Inspection . 7
8.1 Testing procedures and types of documents . 7
8.2 Frequency of testing . 7
8.3 Tests to be carried out for specific inspection . 7
8.3.1 General. 7
8.3.2 Visual and dimensional inspection . 7
9 Test methods . 7
9.1 Chemical analysis . 7
9.2 Hardness and hardenability tests . 8
9.2.1 Verification of hardness . 8
9.2.2 Verification of hardenability . 8
9.3 Retests . 8
10 Marking . 8
Annex A (normative) Supplementary or special requirements .30
Annex B (informative) Designation of steels given in this document and of comparable
grades covered in various designation systems.32
ISO 683-3:2019(E)
Annex C (informative) Dimensional standards applicable to products complying with this
document .34
Annex D (informative) Classification of steel grades according to minimum tensile strength
as a function of diameter after hardening and tempering at 200 °C .35
Bibliography .36
iv © ISO 2019 – All rights reserved

ISO 683-3:2019(E)
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO’s adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see www .iso
.org/iso/foreword .html.
This document was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 4, Heat
treatable and alloy steels.
This third edition cancels and replaces the second edition (ISO 683-3:2016), which has been technically
revised. The main changes compared with the previous edition are as follows:
a
— in Table 1, footnote has been added;
e
— in Table 3, footnote has been changed.
A list of all parts in the ISO 683 series can be found on the ISO website.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/members .html.
INTERNATIONAL STANDARD ISO 683-3:2019(E)
Heat-treatable steels, alloy steels and free-cutting steels —
Part 3:
Case-hardening steels
1 Scope
This document specifies the technical delivery requirements for
— semi-finished products, hot formed, e.g. blooms, billets, slabs (see NOTE 1),
— bars (see NOTE 1),
— wire rod,
— finished flat products, and
— hammer or drop forgings (see NOTE 1)
manufactured from the case-hardening non-alloy or alloy steels listed in Table 3 and supplied in one
of the heat-treatment conditions given for the different types of products in Table 1 and in one of the
surface conditions given in Table 2.
The steels are, in general, intended for the manufacture of case-hardened machine parts.
NOTE 1 Hammer-forged semi-finished products (blooms, billets, slabs, etc.), seamless rolled rings and
hammer-forged bars are covered under semi-finished products or bars and not under the term “hammer and
drop forgings”.
NOTE 2 For International Standards relating to steels complying with the requirements for the chemical
composition in Table 3, however, supplied in other product forms or treatment conditions than given above or
intended for special applications, and for other related International Standards, see the Bibliography.
In special cases, variations in these technical delivery requirements or additions to them can form the
subject of an agreement at the time of enquiry and order (see 5.2 and Annex A).
In addition to this document, the general technical delivery requirements of ISO 404 are applicable.
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 377, Steel and steel products — Location and preparation of samples and test pieces for mechanical testing
ISO 404, Steel and steel products — General technical delivery requirements
ISO 642:1999, Steel — Hardenability test by end quenching (Jominy test)
ISO 643, Steels — Micrographic determination of the apparent grain size
ISO 4885, Ferrous materials — Heat treatments — Vocabulary
ISO 4948-1, Steels — Classification — Part 1: Classification of steels into unalloyed and alloy steels based
on chemical composition
ISO 683-3:2019(E)
ISO 4948-2, Steels — Classification — Part 2: Classification of unalloyed and alloy steels according to main
quality classes and main property or application characteristics
ISO/TS 4949, Steel names based on letter symbols
ISO 4967, Steel — Determination of content of non-metallic inclusions — Micrographic method using
standard diagrams
ISO 6506-1, Metallic materials — Brinell hardness test — Part 1: Test method
ISO 6508-1, Metallic materials — Rockwell hardness test — Part 1: Test method
ISO 6929, Steel products — Vocabulary
ISO 7788, Steel — Surface finish of hot-rolled plates and wide flats — Delivery requirements
ISO 9443, Surface quality classes for hot-rolled bars and wire rod
ISO/TR 9769, Steel and iron — Review of available methods of analysis
ISO 10474, Steel and steel products — Inspection documents
ISO 14284, Steel and iron — Sampling and preparation of samples for the determination of chemical
composition
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 377, ISO 4885, ISO 4948-1,
ISO 4948-2, ISO 6929, ISO 14284 and the following apply.
a
NOTE For deviations from these terms and definitions, see NOTE 1 of the Scope and footnote of Table 2.
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
case-hardening steels
steels with a relatively low carbon content, which are carburized or carbonitrided on their surface and
subsequently hardened
Note 1 to entry: These steels, after hardening, have a high degree of hardness in the surface zone and good
resistance to wear, while the core material is characterized principally by extreme toughness.
Note 2 to entry: Further, possibilities for heat treatment of case-hardening steels are, for example, nitrocarburizing
and nitriding.
3.2
non-alloy steel
as defined in ISO 4948-1
3.3
alloy steel
as defined in ISO 4948-1
2 © ISO 2019 – All rights reserved

ISO 683-3:2019(E)
4 Classification and designation
4.1 Classification
The classification of the relevant steel grades is in accordance with ISO 4948-1 and ISO 4948-2. Steel
grades C10E, C10R, C15E, C15R, C16E, C16R and 22Mn6 are non-alloy special steels. All other steel
grades covered by this document are alloy special steels.
4.2 Designation
For the steel grades covered by this document, the steel names as given in the relevant tables shall be
allocated in accordance with ISO/TS 4949.
A comparison between the designation of steels given in this document with various designation
systems is given in Annex B.
5 Information to be supplied by the purchaser
5.1 Mandatory information
The following information shall be supplied by the purchaser at the time of enquiry and order:
a) quantity to be delivered;
b) designation of the product form (slab, bloom, billet, round bar or square bar, wire rod, wide flats,
sheet, plate, strip, forging, etc.);
c) either the designation of the dimensional standard(s) and the dimensions and tolerances selected
from this or these (see 7.8) or, for example, in the case of drop forgings, the designation of the
drawing or any other document covering the dimensions and tolerances required for the product;
d) a reference to this document, i.e. ISO 683-3;
e) the designation of the steel type given in Table 3;
f) standard designation for a test report 2.2 or, if required, any other type of inspection document
in accordance with ISO 10474 (or in accordance with another regional standard, e.g. EN 10204 or
JIS G 0415).
5.2 Options and/or supplementary or special requirements
A number of options are specified in this document and listed below. If the purchaser does not indicate
the wish to implement any of these options, the products will be supplied in accordance with the basic
specifications of this document (see 5.1):
a) if a heat-treatment condition other than the untreated condition is required, the symbol for this
other condition (see Table 1, column 2);
b) if a surface condition other than “hot worked” or a special surface quality is required, the surface
condition (see Table 2) and the surface quality (see 7.7.3);
c) any requirement for restricted hardenability scatter bands for alloy steels (+HH, +HL; see 7.1.1,
Table 6 and Figure 1);
d) if any supplementary requirement shall be complied with, the symbol and, where necessary, the
details of this supplementary requirement (see Annex A);
e) any requirement for the verification of non-metallic inclusion content (see 7.5);
ISO 683-3:2019(E)
f) verification of hardenability and, if agreed, the information about calculation of the hardenability
(see 9.2.2);
g) any requirement concerning suitability of bars and rod for bright drawing (see 7.7.4);
h) any requirement relating to removal of surface defects (see 7.7.5).
5.3 Ordering example
EXAMPLE 50 hot-rolled round bars in accordance with ISO 1035-1 with a nominal diameter of 40 mm and
a nominal length of 8 000 mm with diameter tolerance according to class S and with length tolerance according
to class L2 of ISO 1035-4 made of steel grade ISO 683-3, 20MnCr5 (see Table 3) in the heat-treatment condition
annealed (+A), surface blast cleaned (+BC) (see Table 2), product analysis/option A.3 with an inspection
certificate 3.1 in accordance with ISO 10474.
50 Round bars ISO 1035 – 40,0S × 8 000L2
ISO 683-3 – 20MnCr5+A+BC, Option A.3
ISO 10474 – 3.1
6 Manufacturing process
6.1 General
The manufacturing process of the steel and of the products is, with the restrictions given by the
requirements in 6.2 to 6.4, left to the discretion of the manufacturer.
For minimum reduction ratio or minimum thickness deformation ratio of rolled and forged products,
see A.4.
6.2 Deoxidation
All steels shall be deoxidized.
6.3 Heat-treatment condition and surface condition at delivery
6.3.1 Normal condition at delivery
Unless otherwise agreed at the time of enquiry and order, the products shall be delivered in the
untreated condition, i.e. hot-worked condition.
6.3.2 Particular heat-treatment condition
If so agreed at the time of enquiry and order, the products shall be delivered in one of the heat-treatment
conditions given in Table 1, row numbers 3 to 8.
6.3.3 Particular surface conditions
If so agreed at the time of enquiry and order, the products shall be delivered in one of the particular
surface conditions given in Table 2, row numbers 3 to 6.
6.4 Traceability of the cast
The products shall be traceable to the cast, see Clause 10.
4 © ISO 2019 – All rights reserved

ISO 683-3:2019(E)
7 Requirements
7.1 Chemical composition, hardness and hardenability
7.1.1 General
Table 1 gives a survey on combinations of usual heat-treatment conditions at delivery, product forms
and requirements as specified in Tables 3 to 7 (chemical composition, hardenability, maximum hardness
and hardness range).
7.1.2 Hardenability
Unless otherwise agreed for alloy steels, the hardenability requirements given in Table 5 apply. If
agreed at the time of enquiry and order, alloy steels with restricted hardenability scatter bands given
in Table 6 or shown in Figure 1 shall be supplied.
A classification of steel grades according to minimum tensile strength as a function of diameter after
hardening and tempering is given in Annex D.
7.1.3 Chemical composition
The chemical composition determined by cast analysis shall comply with the values in Table 3.
Permissible deviations between the limiting values for cast analysis and the values for product analysis
are given in Table 4.
The product analysis shall be carried out when specified, at the time of the enquiry and order (see A.3).
7.2 Machinability
All steels are machinable in the conditions “soft-annealed”, “treated to hardness range”, “treated to
ferrite/pearlite structure” and “normalized.
Where improved machinability is required, the grades with a specified sulfur range should be ordered
and/or with a specific treatment to improve machinability (see also Table 3, footnote b).
7.3 Cold shearability
7.3.1 Under suitable shearing conditions (avoiding local stress peaks, preheating, application of blades
with a profile adapted to that of the product, etc.), all steels are cold shearable in the condition “soft-
annealed”.
7.3.2 Steel grades 28Cr4, 28CrS4, 20MnCr5, 20MnCrS5, 24CrMo4, 24CrMoS4, 22CrMoS3-5, 20MoCr4,
20MoCrS4, 16NiCr4, 16NiCrS4, 18NiCr5-4, 17CrNi6-6, 15NiCr13, 17NiCrMo6-4 and 18CrNiMo7-6, are,
under suitable conditions, also cold shearable when delivered in the condition “treated to improve
shearability” with the hardness requirements given in Table 7.
7.3.3 The non-alloy steels and steels 17Cr3, 17CrS3, 20Cr4, 20CrS4, 16MnCr5, 16MnCrS5, 16MnCrB5,
18CrMo4, 18CrMoS4, 20NiCrMo2-2 and 20NiCrMoS2-2 are, under suitable conditions, cold shearable
when delivered in the untreated condition.
7.4 Grain size
Unless otherwise agreed at the time of enquiry and order, the steel shall show a fine grain structure
with an austenitic grain size of 5 and finer, when tested in accordance with ISO 643. For verification,
see A.1.
ISO 683-3:2019(E)
7.5 Non-metallic inclusions
7.5.1 Microscopic inclusions
The special steels shall have a certain degree of cleanness, however, verification of the non-metallic
inclusion content requires a special agreement. If there is such an agreement at the time of enquiry and
order, the microscopic non-metallic inclusion content shall be determined to an agreed procedure and
within agreed limits in accordance with ISO 4967 or another regional standard.
For grades with specified minimum sulfur content, the agreement should not include sulphides.
7.5.2 Macroscopic inclusions
This requirement is applicable to the verification of the macroscopic inclusions in special steels. If
verification is agreed, the method and acceptance limits shall be agreed at the time of enquiry and order.
7.6 Internal soundness
Where appropriate, requirements relating to the internal soundness of the products shall be agreed at
the time of inquiry and order (see A.2).
7.7 Surface condition
7.7.1 All products shall have a smooth surface finish appropriate to the manufacturing processes
applied.
7.7.2 Minor surface imperfections which may occur under normal manufacturing conditions, such as
prints originating from rolled-in scale, are not to be regarded as defects.
7.7.3 Bars and wire rod are delivered with surface class A in accordance with ISO 9443 and hot-rolled
plates and wide flats shall be delivered with a surface in accordance with ISO 7788, unless otherwise
agreed at the time of enquiry and order.
Where no International Standard on the surface quality of steel products exists, detailed requirements
referring to this characteristic shall, where appropriate, be agreed at the time of enquiry and order.
It is more difficult to detect and eliminate surface discontinuities from coiled products than from cut
lengths. This should be taken into account when agreements on surface quality are made.
NOTE Bars and wire rod for cold heading and cold extrusion are covered fully by ISO 4954.
7.7.4 If suitability of bars and rod for bright drawing is required, this shall be agreed at the time of
enquiry and order.
7.7.5 Removal of surface discontinuities by welding shall only be permitted with the approval of the
customer or his/her representative. If surface discontinuities are repaired, the method and maximum
depth of removal shall be agreed at the time of enquiry and order.
7.8 Shape, dimensions and tolerances
The nominal dimensions, tolerances on dimensions and shape of the product shall be agreed at the time
of enquiry and order, if possible, with reference to the dimensional standards applicable (see Annex C).
6 © ISO 2019 – All rights reserved

ISO 683-3:2019(E)
8 Inspection
8.1 Testing procedures and types of documents
8.1.1 Products complying with this document shall be ordered and delivered with one of the inspection
documents as specified in ISO 10474 or another standard, e.g. regional standards EN 10204 or JIS G
0415. The type of document shall be agreed upon at the time of enquiry and order. If the order does not
contain any specification of this type, a test report shall be issued.
8.1.2 If, in accordance with the agreements made at the time of enquiry and order, a test report 2.2 is
to be provided, this shall cover the following information:
a) confirmation that the material complies with the requirements of the order;
b) results of the cast analysis for all elements specified in Table 3 for the steel grade concerned.
8.1.3 If, in accordance with the agreements in the order, an inspection certificate 3.1 or 3.2 is to be
provided, the specific inspections and tests described in 8.3 and Clause 9 shall be carried out and the
results shall be confirmed in the inspection certificate.
In addition, the inspection certificate shall cover the following:
a) confirmation that the material complies with the requirements of the order;
b) results of the cast analysis for all elements specified in Table 3 for the steel grade concerned;
c) results of all inspections and tests ordered by supplementary requirements (see Annex A);
d) the symbol, letters or numbers relating the test certificates, the test pieces and products to each other.
8.2 Frequency of testing
The amount of testing, the sampling conditions and the test methods to be applied for the verification of
the requirements shall be in accordance with Table 9.
8.3 Tests to be carried out for specific inspection
8.3.1 General
For non-alloy steels and for alloy steels without requirements concerning the verification of
hardenability, the hardness requirements according to Table 1, columns 8.2 and 9.2 and Table 7 are to
be verified.
For alloy steels being ordered with the verification of hardenability, unless otherwise agreed, only the
hardenability requirements according to Tables 5 and 6 are to be verified.
8.3.2 Visual and dimensional inspection
A sufficient number of products shall be inspected to ensure the compliance with the specification.
9 Test methods
9.1 Chemical analysis
The choice of a suitable physical or chemical analytical method for the analysis shall be at the discretion
of the manufacturer. In cases of dispute, the method product analysis used shall be agreed taking into
account the relevant existing International Standards.
ISO 683-3:2019(E)
The list of available International Standards on chemical analysis is given in ISO/TR 9769.
9.2 Hardness and hardenability tests
9.2.1 Verification of hardness
For products in the heat-treatment conditions +S (treated to improve shearability), +A (soft-annealed),
+TH (treated to hardness range), +FP (treated to ferritic-pearlitic structure) and +N (normalized), the
hardness shall be measured in accordance with ISO 6506-1 (see Tables 7 and 9).
9.2.2 Verification of hardenability
For alloy steels, as far as available, the manufacturer has the option to verify the hardenability by
calculation. The calculation method is left to the discretion of the manufacturer. If agreed at the time
of enquiry and order, the manufacturer shall give sufficient information about the calculation for the
customer to confirm the result.
If a calculation formula is not available or in the case of dispute, an end quench hardenability test shall
be carried out in accordance with ISO 642 and Table 9. The temperature for quenching shall comply
with Table 8. The hardness values shall be determined in accordance with ISO 6508-1, scale C.
9.3 Retests
Retests of case hardening steels and criteria shall be as specified in ISO 404.
10 Marking
The manufacturer shall mark the products or the bundles or boxes containing the products in a suitable
way, so that the identification of the cast, the steel type and the origin of the delivery is possible (see A.5).
8 © ISO 2019 – All rights reserved

ISO 683-3:2019(E)
Table 1 — Combinations of usual heat-treatment conditions at delivery, product forms and requirements according to Tables 3 to 7
No. 1 2 3 4 5 6 7 8 9
x indicates applicable to Applicable requirements
Heat-
treatment
Semi- Hammer Non-alloy steel grades Alloy steel grades
1 Symbol
Wire Flat
condition at
finished Bars and drop
rod products
8.1 8.2 9.1 9.2 9.3
delivery
products forgings
None
2 Untreated x x x x x —
or +U
Treated to
Column
3 improve +S x x — — —
Hardenability values
+S
shearability
according to Table 5 or 6
Chemical
Column
4 Soft-annealed +A x x x x x If option 5.2 f) is
composition As in col-
+A
ordered, the
according umn 8 (see
Brinell
Treated to Column
b verification of
to footnote
5 +TH — x x x x hardness
hardness range +TH
hardenability and, if
Tables 3 to Table 3)
according
agreed, the information
and 4
Treated to
to Table 7
Column
about calculation of the
6 ferrite- pearlite +FP — x — — x
+FP
hardenability (see 9.2.2)
a
structure
Normalized or
Column
7 normalizing +N — — — x —
+N
forming
Other treatment conditions, for example certain annealing conditions to achieve a certain structure, may be agreed at the time of enquiry
and order.
8 Others
The condition “annealed to achieve a spheroidization of the carbides (+AC)”, as required for cold heading and cold extrusion, is covered
in ISO 4954.
a
For products of certain grades, a 100 % ferrite-pearlitic structure cannot be achieved, despite an adapted heat-treatment, e.g. isothermal tempering for bars of 18CrNiMo7–6
gives F+P+B structure at any time.

ISO 683-3:2019(E)
Table 2 — Surface condition at delivery
No. 1 2 3 4 5 6 7 8 9
1 Surface condition at Symbol x indicates in general applicable to Notes
delivery
Semi- Bars Wire Flat Hammer
finished rod products and drop
products forgings
(as (see NOTE 1 to
blooms, Clause 1)
billets)
a
2 Unless Hot None or x x x x x —
otherwise worked +HW
agreed
c
3 Particular Hot +PI x x x x x —
conditions worked
supplied by and pickled
agreement
4 Hot +BC x x x x x
worked
and blast
cleaned
b
5 Hot +RM — x x — x
worked
and rough
machined
6 Others — — x x x x
a
The term “hot worked” also includes the continuously cast (+CC) condition in the case of semi-finished products.
b
Until the term “rough machined” is defined by, for example, machining allowances, the details are to be agreed at the
time of enquiry and order.
c
In addition, certain surface treatments, such as oiled, limed or phosphated, may be agreed upon.
10 © ISO 2019 – All rights reserved

ISO 683-3:2019(E)
a,b,c
Table 3 — Steel grades and chemical composition (applicable to cast analysis)
d
Mass fraction
%
Steel name
Cu
e
C Si Mn P S Cr Mo Ni
and B
Non-alloy steels
C10E 0,035
0,07 to 0,15 to 0,30 to
0,025 0,40 0,10 0,40 Cu: 0,30
0,020 to
0,13 0,40 0,60
C10R
0,040
C15E 0,035
0,12 to 0,15 to 0,30 to
0,025 0,40 0,10 0,40 Cu: 0,30
0,020 to
0,18 0,40 0,60
C15R
0,040
C16E 0,035
0,12 to 0,15 to 0,60 to
0,025 0,40 0,10 0,40 Cu: 0,30
0,020 to
0,18 0,40 0,90
C16R
0,040
0,18 to 0,10 to 1,30 to
22Mn6 0,025 0,035 0,40 0,10 0,40 Cu: 0,30
0,25 0,40 1,65
Alloy steels
17Cr3 0,035
0,14 to 0,15 to 0,60 to 0,70 to
0,025 — — Cu: 0,40
0,020 to
0,20 0,40 0,90 1,00
17CrS3
0,040
20Cr4 0,035
0,17 to 0,15 to 0,60 to 0,90 to
0,025 — — Cu: 0,40
0,020 to
0,23 0,40 0,90 1,20
20CrS4
0,040
28Cr4 0,035
0,24 to 0,60 to 0,90 to
0,40 0,025 — — Cu: 0,40
0,020 to
0,31 0,90 1,20
28CrS4
0,040
16MnCr5 0,035
0,14 to 0,15 to 1,00 to 0,80 to
0,025 — — Cu: 0,40
0,020 to
0,19 0,40 1,30 1,10
16MnCrS5
0,040
Cu: 0,40
0,14 to 0,15 to 1,00 to 0,80 to
16MnCrB5 0,025 0,035 — — B: 0,0008
0,19 0,40 1,30 1,10
f
to 0,0050
20MnCr5 0,035
0,17 to 0,15 to 1,10 to 1,00 to
0,025 — — Cu: 0,40
0,020 to
0,22 0,40 1,40 1,30
20MnCrS5
0,040
Elements not quoted in this table shall not be intentionally added to the steel without the agreement of the purchaser, other
than for the purpose of finishing the heat. All reasonable precautions shall be taken to prevent the addition of such elements
from scrap or other materials used in manufacture, which affect the hardenability, mechanical properties and applicability.
a
For steels with hardenability requirements (see Tables 5 and 6), except for phosphorus and sulfur, insignificant
deviations from the limits for cast analysis are permissible; these deviations shall, however, not exceed in the case of
carbon ±0,01 % and, in all other cases, the values according to Table 4.
b
Steels with improved machinability either by higher sulfur levels up to about 0,10 % S (including controlled sulphide
morphology) or lead additions may be supplied on request. In the first case, the upper limit of the manganese content may
be increased by 0,15 %.
c
Additional case-hardening steels, predominantly used for bearings, are covered by ISO 683-17.
d
Maximum values unless otherwise stated.
e
Steels may be supplied with a lowe
...