Steels - Determination of the depth of decarburization (ISO 3887:2017)

This document defines the decarburization and specifies three methods of measuring the depth of
decarburization of steel products.

Stahl - Bestimmung der Entkohlungstiefe (ISO 3887:2017)

Diese Internationale Norm definiert die Entkohlung und legt fünf Verfahren zur Bestimmung der Ent¬koh-lungs¬tiefe von Stahlerzeugnissen fest.

Aciers - Détermination de la profondeur de décarburation (ISO 3887:2017)

L'ISO 3887 :2017 définit la décarburation et spécifie trois méthodes de mesure de la profondeur de décarburation des produits acier.

Jekla - Določevanje globine razogličene plasti (ISO 3887:2017)

Ta dokument opredeljuje razogljičenje in določa tri metode za merjenje globine razogljičenja jeklenih izdelkov.

General Information

Status
Published
Public Enquiry End Date
30-Sep-2016
Publication Date
07-May-2018
Current Stage
6060 - National Implementation/Publication (Adopted Project)
Start Date
21-Feb-2018
Due Date
28-Apr-2018
Completion Date
08-May-2018

RELATIONS

Buy Standard

Standard
SIST EN ISO 3887:2018
English language
20 pages
sale 10% off
Preview
sale 10% off
Preview

e-Library read for
1 day
Draft
oSIST prEN ISO 3887:2016
English language
19 pages
sale 10% off
Preview
sale 10% off
Preview

e-Library read for
1 day

Standards Content (sample)

SLOVENSKI STANDARD
SIST EN ISO 3887:2018
01-julij-2018
1DGRPHãþD
SIST EN ISO 3887:2004
-HNOD'RORþHYDQMHJORELQHUD]RJOLþHQHSODVWL ,62
Steels - Determination of the depth of decarburization (ISO 3887:2017)
Stahl - Bestimmung der Entkohlungstiefe (ISO 3887:2017)
Aciers - Détermination de la profondeur de décarburation (ISO 3887:2017)
Ta slovenski standard je istoveten z: EN ISO 3887:2018
ICS:
77.040.99 Druge metode za Other methods of testing of
preskušanje kovin metals
77.080.20 Jekla Steels
SIST EN ISO 3887:2018 en,fr,de

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

---------------------- Page: 1 ----------------------
SIST EN ISO 3887:2018
---------------------- Page: 2 ----------------------
SIST EN ISO 3887:2018
EN ISO 3887
EUROPEAN STANDARD
NORME EUROPÉENNE
January 2018
EUROPÄISCHE NORM
ICS 77.040.99 Supersedes EN ISO 3887:2003
English Version
Steels - Determination of the depth of decarburization (ISO
3887:2017)

Aciers - Détermination de la profondeur de Stahl - Bestimmung der Entkohlungstiefe (ISO

décarburation (ISO 3887:2017) 3887:2017)
This European Standard was approved by CEN on 21 November 2017.

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

© 2018 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 3887:2018 E

worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 3887:2018
EN ISO 3887:2018 (E)
Contents Page

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

---------------------- Page: 4 ----------------------
SIST EN ISO 3887:2018
EN ISO 3887:2018 (E)
European foreword

This document (EN ISO 3887:2018) has been prepared by Technical Committee ISO/TC 17 “Steel” in

collaboration with Technical Committee ECISS/TC 101 “Test methods for steel (other than chemical

analysis)” 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 July 2018, and conflicting national standards shall be

withdrawn at the latest by July 2018.

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 3887:2003.

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 3887:2017 has been approved by CEN as EN ISO 3887:2018 without any modification.

---------------------- Page: 5 ----------------------
SIST EN ISO 3887:2018
---------------------- Page: 6 ----------------------
SIST EN ISO 3887:2018
INTERNATIONAL ISO
STANDARD 3887
Third edition
2017-11
Steels — Determination of the depth
of decarburization
Aciers — Détermination de la profondeur de décarburation
Reference number
ISO 3887:2017(E)
ISO 2017
---------------------- Page: 7 ----------------------
SIST EN ISO 3887:2018
ISO 3887:2017(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2017, Published in Switzerland

All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2017 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 3887:2018
ISO 3887:2017(E)
Contents Page

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

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

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

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Sampling ........................................................................................................................................................................................................................ 2

5 Measuring methods ........................................................................................................................................................................................... 2

5.1 General ........................................................................................................................................................................................................... 2

5.2 Metallographic method.................................................................................................................................................................... 3

5.2.1 General...................................................................................................................................................................................... 3

5.2.2 Selection and preparation of the sample .................................................................................................... 3

5.2.3 Measurement ...................................................................................................................................................................... 3

5.3 Methods for measuring the micro-indentation hardness .................................................................................. 5

5.3.1 General...................................................................................................................................................................................... 5

5.3.2 Selection and preparation of the sample .................................................................................................... 7

5.3.3 Measurement ...................................................................................................................................................................... 7

5.4 Methods of determination of the carbon content ..................................................................................................... 9

5.4.1 General...................................................................................................................................................................................... 9

5.4.2 Chemical analysis ............................................................................................................................................................ 9

5.4.3 Spectrographic analysis ............................................................................................................................................. 9

5.4.4 Interpretation of the results (chemical and spectrographic methods) ............................ 9

5.4.5 Electron probe microanalysis (EPMA) .......................................................................................................... 9

5.4.6 Glow discharge optical emission spectrometry (GDOES) .........................................................10

6 Test report ................................................................................................................................................................................................................10

Annex A (informative) Examples of typical decarburization microstructure ........................................................12

© ISO 2017 – All rights reserved iii
---------------------- Page: 9 ----------------------
SIST EN ISO 3887:2018
ISO 3887:2017(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 on 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 the following

URL: www.iso.org/iso/foreword.html.

This document was prepared by Technical Committee ISO/TC 17, Steel, Subcommittee SC 7, Methods of

testing (other than mechanical tests and chemical analysis).

This third edition cancels and replaces the second edition (ISO 3887:2003), which has been technically

revised. The following changes have been made:

— the scope has been expanded from “non-alloy and low-alloy steels” to “steel products”;

— the definitions of “partial decarburization” and “complete decarburization” have been modified;

— the term “depth of ferrite decarburization” has been deleted;

— the terms “depth profile of carbon content” and “depth profile of hardness” have been added;

— more measurement details for the micro-indentation hardness method have been added;

— two new methods of measuring the carbon depth profile, by GDOES and EPMA, have been added;

— examples of typical decarburization microstructures have been added.
iv © ISO 2017 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 3887:2018
INTERNATIONAL STANDARD ISO 3887:2017(E)
Steels — Determination of the depth of decarburization
1 Scope

This document defines the decarburization and specifies three methods of measuring the depth of

decarburization of steel products.
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 4545-1, Metallic materials —Knoop hardness test — Part 1: Test method
ISO 6507-1, Metallic materials — Vickers hardness test — Part 1: Test method

ISO 9556, Steel and iron — Determination of total carbon content — Infrared absorption method after

combustion in an induction furnace

ISO 14594, Microbeam analysis — Electron probe microanalysis — Guidelines for the determination of

experimental parameters for wavelength dispersive spectroscopy

ISO 14707, Surface chemical analysis — Glow discharge optical emission spectrometry (GD-OES) —

Introduction to use

ISO 15349-2, Unalloyed steel — Determination of low carbon content — Part 2: Infrared absorption method

after combustion in an induction furnace (with preheating)
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.

ISO and IEC maintain terminological databases for use in standardization at the following addresses:

— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
decarburization
reduction of carbon content from the surface zone of the steel
Note 1 to entry: A distinction is made between

a) partial decarburization, d , measured as the distance from the point at which the carbon content exceeds the

solubility limit in ferrite, becoming visible as e.g. pearlite, to the point at which there is no more visible difference

to the core carbon concentration, and

b) complete decarburization, also called ferrite decarburization, d , measured as the distance between the

surface of the product and the point up to which the carbon content is below the solubility limit of carbon in

ferrite so that only ferrite is present.

Note 2 to entry: The depth of complete decarburization as described in b) is determined by examination of the

microstructure.
© ISO 2017 – All rights reserved 1
---------------------- Page: 11 ----------------------
SIST EN ISO 3887:2018
ISO 3887:2017(E)
3.2
depth of functional decarburization

distance between the surface of the product and the point at which the carbon content or hardness is at

the level where the performance of the product would be unaffected by a reduction in carbon content

(i.e. at the minimum level specified in the product standard)
3.3
depth of total decarburization

distance between the surface of the product and the point at which the carbon content is that of the

unaffected core, the sum of the partial and the complete decarburization d + d being designated by the

3 1
letters DD
EXAMPLE DD = 0,08 mm.
Note 1 to entry: Expressed in millimetres.
3.4
depth profile of carbon content

curve indicating the relationship between the perpendicular distance from the surface of steel material

and the carbon content
3.5
depth profile of hardness

curve indicating the relationship between the perpendicular distance from the surface of steel material

and the hardness
4 Sampling

Samples should be taken at locations that are representative of the bulk specimen. The location

and number of samples taken depend on the nature of the material to be tested and are defined by

agreement between the parties concerned.

Specimens for the metallographic methods or micro-indentation hardness tests or electron probe

microanalysis should be cut from the bulk specimen perpendicular to the longitudinal axis of the product

so that measurements are made on a transverse plane. This procedure permits the determination of

the variation of decarburization around the periphery of the specimen. Unless otherwise specified, the

corner parts which can generate abnormal decarburization shall not be included. For specimens up to

about 2,5 cm diameter, the entire cross-section is polished and examined. For larger cross-sections,

one or more specimens shall be prepared to assess variations in surface decarburization. The sampling

scheme for large sections should be determined by agreement between the parties concerned.

Specimens for chemical analytical methods shall be of sufficient length so that the weight of incremental

turnings is adequate for chemical analysis or the size of milled surfaces is large enough for sparking yet

small enough to fit in the specimen holder.
5 Measuring methods
5.1 General

The choice of the method and its accuracy depend on the degree of decarburization, the microstructure,

the carbon content of the product examined and the shape of the component.
The usual methods employed on finished products are as follows:
— metallographic method (see 5.2);
2 © ISO 2017 – All rights reserved
---------------------- Page: 12 ----------------------
SIST EN ISO 3887:2018
ISO 3887:2017(E)

— method for measuring the micro-indentation hardness (Vickers or Knoop) for steels in the hardened

or quenched and tempered condition (see 5.3);
— method for the det
...

SLOVENSKI STANDARD
oSIST prEN ISO 3887:2016
01-oktober-2016
-HNOD'RORþHYDQMHJORELQHUD]RJOLþHQHSODVWL ,62',6
Steels - Determination of the depth of decarburization (ISO/DIS 3887:2016)
Stahl - Bestimmung der Entkohlungstiefe (ISO/DIS 3887:2016)
Aciers - Détermination de la profondeur de décarburation (ISO/DIS 3887:2016)
Ta slovenski standard je istoveten z: prEN ISO 3887
ICS:
77.040.99 Druge metode za Other methods of testing of
preskušanje kovin metals
77.080.20 Jekla Steels
oSIST prEN ISO 3887:2016 en,fr,de

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

---------------------- Page: 1 ----------------------
oSIST prEN ISO 3887:2016
---------------------- Page: 2 ----------------------
oSIST prEN ISO 3887:2016
DRAFT INTERNATIONAL STANDARD
ISO/DIS 3887
ISO/TC 17/SC 7 Secretariat: AFNOR
Voting begins on: Voting terminates on:
2016-06-22 2016-09-13
Steels — Determination of depth of decarburization
Aciers — Détermination de la profondeur de décarburation
ICS: 77.040.99
ISO/CEN PARALLEL PROCESSING
This draft has been developed within the International Organization for
Standardization (ISO), and processed under the ISO lead mode of collaboration
as defined in the Vienna Agreement.
This draft is hereby submitted to the ISO member bodies and to the CEN member
bodies for a parallel five month enquiry.
THIS DOCUMENT IS A DRAFT CIRCULATED
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
To expedite distribution, this document is circulated as received from the
IN ADDITION TO THEIR EVALUATION AS
committee secretariat. ISO Central Secretariat work of editing and text
BEING ACCEPTABLE FOR INDUSTRIAL,
composition will be undertaken at publication stage.
TECHNOLOGICAL, COMMERCIAL AND
USER PURPOSES, DRAFT INTERNATIONAL
STANDARDS MAY ON OCCASION HAVE TO
BE CONSIDERED IN THE LIGHT OF THEIR
POTENTIAL TO BECOME STANDARDS TO
WHICH REFERENCE MAY BE MADE IN
Reference number
NATIONAL REGULATIONS.
ISO/DIS 3887:2016(E)
RECIPIENTS OF THIS DRAFT ARE INVITED
TO SUBMIT, WITH THEIR COMMENTS,
NOTIFICATION OF ANY RELEVANT PATENT
RIGHTS OF WHICH THEY ARE AWARE AND TO
PROVIDE SUPPORTING DOCUMENTATION. ISO 2016
---------------------- Page: 3 ----------------------
oSIST prEN ISO 3887:2016
ISO/DIS 3887:2016(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2016, Published in Switzerland

All rights reserved. Unless otherwise specified, 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
Ch. de Blandonnet 8 • CP 401
CH-1214 Vernier, Geneva, Switzerland
Tel. +41 22 749 01 11
Fax +41 22 749 09 47
copyright@iso.org
www.iso.org
ii © ISO 2016 – All rights reserved
---------------------- Page: 4 ----------------------
oSIST prEN ISO 3887:2016
ISO/DIS 3887:2016(E)
Contents Page

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

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

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

3 Terms and definitions ..................................................................................................................................................................................... 1

4 Sampling ........................................................................................................................................................................................................................ 4

5 Measuring methods ........................................................................................................................................................................................... 4

5.1 General ........................................................................................................................................................................................................... 4

5.2 Micrographic method ........................................................................................................................................................................ 4

5.2.1 General...................................................................................................................................................................................... 4

5.2.2 Selection and preparation of the sample .................................................................................................... 5

5.2.3 Measurement ...................................................................................................................................................................... 5

5.3 Methods for measuring the micro-indentation hardness .................................................................................. 6

5.3.1 General...................................................................................................................................................................................... 6

5.3.2 Selection and preparation of the sample .................................................................................................... 6

5.3.3 Measurement ...................................................................................................................................................................... 6

5.4 Methods of determination of the carbon content ..................................................................................................... 9

5.4.1 General...................................................................................................................................................................................... 9

5.4.2 Chemical analysis .........................................................................................................................................................10

5.4.3 Spectrographic analysis ..........................................................................................................................................10

5.4.4 Interpretation of the results (chemical and spectrographic methods) .........................10

5.5 Method measuring the depth profile of the carbon content by EPMA ................................................10

5.5.1 General...................................................................................................................................................................................10

5.5.2 Preparation of the sample ....................................................................................................................................10

5.5.3 Measurement ...................................................................................................................................................................10

5.6 Method measuring the depth profile of the carbon content by GDOES ..............................................11

5.6.1 General...................................................................................................................................................................................11

5.6.2 Preparation of the samples ..................................................................................................................................11

5.6.3 Measurement ...................................................................................................................................................................11

6 Test report ................................................................................................................................................................................................................11

Annex A (informative) Examples of typical decarburization microstructure ........................................................13

Bibliography .............................................................................................................................................................................................................................15

© ISO 2016 – All rights reserved iii
---------------------- Page: 5 ----------------------
oSIST prEN ISO 3887:2016
ISO/DIS 3887:2016(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. 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. 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

The committee responsible for ISO/DIS 3887 is ISO/TC 17, Steel, Subcommittee SC 7, Methods of testing

(other than mechanical tests and chemical analysis).

This third edition cancels and replaces the second edition (ISO 3887:2003), which has been technically

revised.
iv © ISO 2016 – All rights reserved
---------------------- Page: 6 ----------------------
oSIST prEN ISO 3887:2016
DRAFT INTERNATIONAL STANDARD ISO/DIS 3887:2016(E)
Steels — Determination of depth of decarburization
1 Scope

This International Standard defines the decarburization and specifies five methods of measuring the

depth of decarburization of steel products.
2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated

references, the latest edition of the referenced document (including any amendments) applies.

ISO 4545-1, Metallic materials - Knoop hardness test - Part 1: Test method
ISO 6507-1, Metallic materials — Vickers hardness test — Part 1: Test method

ISO 9556, Steel and iron — Determination of total carbon content — Infrared absorption method after

combustion in an induction furnace

ISO 15349-2, Unalloyed steel — Determination of low carbon content — Part 2: Infrared absorption method

after combustion in an induction furnace (with preheating)

ISO 14594, Microbeam analysis — Electron probe microanalysis — Guidelines for the determination of

experimental parameters for wavelength dispersive spectroscopy

ISO 14707, Surface chemical analysis — Glow discharge optical emission spectrometry (GD-OES) —

Introduction to use
3 Terms a nd definiti ons
For the purposes of this document, the following terms and definitions apply.
3.1
decarburization
loss of carbon from the surface zone of the steel where the loss is:
a) either partial decarburization, d ;

b) or complete decarburization, also called ferrite decarburization, d , measured as the distance

between the surface of the product and the point up to which carbon is below the solubility limit of

carbon in ferrite so that only ferrite is present.

Note 1 to entry: The depth of complete decarburization as described in b) is determined by examination of the

microstructure.
3.2
depth of functional decarburization

distance between the surface of the product and the point at which the carbon content or hardness is

at the level where the performance of the product would be unaffected by a reduction in carbon (i.e., at

the minimum level specified in the product standard)
© ISO 2016 – All rights reserved 1
---------------------- Page: 7 ----------------------
oSIST prEN ISO 3887:2016
ISO/DIS 3887:2016(E)
3.3
depth of total decarburization

distance between the surface of the product and the point at which the carbon content is that of the

unaffected core, the sum of the partial and the complete decarburization d + d being designated by

3 1
the letters DD and expressed in millimetres, e.g., DD = 0,08 mm

Note 1 to entry: The various bands of decarburization are shown schematically in Figure 1. The boundaries

separating the various types of decarburization are shown as hatched bands with the width of the band

illustrating the practical variability in measurements due to the uncertainty of interpretation.

3.4
dep t h pr of i le of c a r b on c ont ent

the curve indicating the relationship between the perpendicular distance from the surface of steel

material and the carbon concentration
3.5
dep t h pr of i le of h a r d ne s s

the curve indicating the relationship between the perpendicular distance from the surface of steel

material and the hardness
2 © ISO 2016 – All rights reserved
---------------------- Page: 8 ----------------------
oSIST prEN ISO 3887:2016
ISO/DIS 3887:2016(E)
Key
a minimum carbon content specified in the product standard
b core carbon content

If the product has undergone a process involving carburization, the definition of the “core” shall form the

subject of an agreement between the parties concerned.

The permissible depth of decarburization shall be specified in the appropriate standard covering the product

or shall be the subject of an agreement between the parties concerned.

Figure 1 — Carbon content as a function of the distance from the surface: schematic

representation for a typical decarburized steel
© ISO 2016 – All rights reserved 3
---------------------- Page: 9 ----------------------
oSIST prEN ISO 3887:2016
ISO/DIS 3887:2016(E)
4 Sampling

4.1 Samples should be taken at locations that are representative of the bulk specimen. The location

and number of samples taken depend on the nature of the material to be tested and will be defined upon

agreements between the manufacturer and purchaser.

4.2 Specimens for the microscopical methods or for micro-indentation hardness tests or by electron

probe microanalysis should be cut from the bulk specimen perpendicular to the longitudinal axis of the

product so that measurements are made on a transverse plane. This procedure permits the determination

of the variation of decarburization around the periphery of the specimen. For specimens up to about 2,5

cm diameter, the entire cross-section is polished and examined. For larger cross-sections, one or more

specimens shall be prepared to assess variations in surface decarburization. The sampling scheme for

large sections should be determined upon mutual agreement between the manufacturer and purchaser.

4.3 Specimens for chemical analytical methods shall be of sufficient length so that the weight of

incremental turnings is adequate for chemical analysis or the size of milled surfaces is large enough for

sparking yet small enough to fit in the specimen holder.
5 Measuring methods
5.1 General

The choice of the method and its accuracy depend on the degree of decarburization, the microstructure,

the carbon content of the product examined and the shape of the component.
The usual methods employed on finished products are:
— a micrographic method (see 5.2);

— a method for measuring the microindentation hardness (Vickers or Knoop) for steels in the hardened

or quenched and tempered condition (see 5.3);

— a method for the determination of the carbon content by chemical or spectrographic analysis (see 5.4);

— a method for measuring the depth profile of the carbon content by electron probe microanalysis

(EPMA) (see 5.5);

— a method for measuring the depth profile of the carbon content by glow discharge optical emission

spectrometry (GDOES) (see 5.6).

The inclusion of several methods of measurement, each having its own sphere of application, avoids

the nec
...

Questions, Comments and Discussion

Ask us and Technical Secretary will try to provide an answer. You can facilitate discussion about the standard in here.