SIST EN ISO 17872:2020
(Main)Paints and varnishes - Guidelines for the introduction of scribe marks through coatings on metallic panels for corrosion testing (ISO 17872:2019)
Paints and varnishes - Guidelines for the introduction of scribe marks through coatings on metallic panels for corrosion testing (ISO 17872:2019)
This document describes methods of scribing coated steel or test-pieces for corrosion tests, where the coating system is applied at dry film thicknesses of less than 500 μm. It is intended as a guideline only, being based on the results of a collaborative trial with no subsequent corrosion testing having been carried out to determine the suitability of the introduced scribe marks for such tests. This document covers the scribing of metallic panels or test pieces (chemically treated or not) made from: - steel; - galvanized steel; - aluminium alloys; - magnesium alloys. It does not cover the scribing of electroplated metal or clad aluminium panels.
Beschichtungsstoffe - Leitfaden zum Anbringen von Ritzen durch eine Beschichtung auf Metallplatten für Korrosionsprüfungen (ISO 17872:2019)
Dieses Dokument legt Verfahren zum Ritzen von beschichtetem Stahl oder von Probenstücken für Korrosionsprüfungen fest, wenn das Beschichtungssystem in Trockenschichtdicken unter 500 μm aufgebracht ist. Es ist als Leitfaden zu sehen, der auf Ergebnissen gemeinsamer Untersuchungen beruht, ohne dass nachfolgend Korrosionsprüfungen durchgeführt wurden, um die Tauglichkeit der angebrachten Ritze für solche Prüfungen zu untersuchen.
Dieses Dokument behandelt das Ritzen von (chemisch vorbehandelten oder nicht vorbehandelten) metallischen Probenplatten oder Probenkörpern aus:
- Stahl;
- galvanisiertem Stahl;
- Aluminiumlegierungen;
- Magnesiumlegierungen.
Es behandelt nicht das Ritzen von verzinktem Metall oder plattierten Aluminiumplatten.
Peintures et vernis - Lignes directrices pour la production de rayures au travers du revêtement de panneaux métalliques en vue des essais de corrosion (ISO 17872:2019)
Le présent document décrit des méthodes de réalisation de rayures sur de l'acier revêtu ou sur des éprouvettes, en vue d'essais de corrosion, sur des systèmes de revêtement dont l'épaisseur de feuil sec est inférieure à 500 µm. Il est fondé sur le résultat d'un essai interlaboratoires, sans essai ultérieur de corrosion pour vérifier le caractère approprié des rayures effectuées, et n'est destiné qu'à donner des lignes directrices.
Le présent document traite de la réalisation de rayures sur des panneaux ou des éprouvettes métalliques (avec ou sans traitement chimique):
— en acier,
— en acier galvanisé,
— en alliages d'aluminium,
— en alliages de magnésium.
Il ne traite pas de la réalisation de rayures sur des panneaux en métal revêtu d'un dépôt électrolytique ou d'un alliage d'aluminium.
Barve in laki - Smernice za uvajanje sledi rezov v premazih na kovinskih ploščah za preskušanje odpornosti proti koroziji (ISO 17872:2019)
Ta dokument opisuje metode rezanja premazanega jekla ali preskusnih kosov za preskuse odpornosti proti koroziji, pri čemer je sistem premaza nanesen z debelino suhega filma, manjšo od 500 μm. Namenjen je izključno kot vodilo, saj temelji na rezultatih primerjalnih preskusov, brez izvedbe dodatnega preskušanja korozije, ki bi se izvedlo za določitev primernosti sledi povzročenih rezov za take preskuse. Ta dokument se navezuje na rezanje kovinskih plošč ali preskusnih kosov (kemično obdelanih ali ne), izdelanih iz: – jekla; – galvaniziranega jekla; – aluminijevih zlitin; – magnezijevih zlitin. Ne uporablja se za rezanje kovin z galvanskimi prevlekami ali prevlečenih aluminijastih plošč.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 17872:2020
01-januar-2020
Nadomešča:
SIST EN ISO 17872:2007
Barve in laki - Smernice za uvajanje sledi rezov v premazih na kovinskih ploščah
za preskušanje odpornosti proti koroziji (ISO 17872:2019)
Paints and varnishes - Guidelines for the introduction of scribe marks through coatings
on metallic panels for corrosion testing (ISO 17872:2019)
Beschichtungsstoffe - Leitfaden zum Anbringen von Ritzen durch eine Beschichtung auf
Metallplatten für Korrosionsprüfungen (ISO 17872:2019)
Peintures et vernis - Lignes directrices pour la production de rayures au travers du
revêtement de panneaux métalliques en vue des essais de corrosion (ISO 17872:2019)
Ta slovenski standard je istoveten z: EN ISO 17872:2019
ICS:
87.040 Barve in laki Paints and varnishes
SIST EN ISO 17872:2020 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
SIST EN ISO 17872:2020
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SIST EN ISO 17872:2020
EN ISO 17872
EUROPEAN STANDARD
NORME EUROPÉENNE
October 2019
EUROPÄISCHE NORM
ICS 87.040 Supersedes EN ISO 17872:2007
English Version
Paints and varnishes - Guidelines for the introduction of
scribe marks through coatings on metallic panels for
corrosion testing (ISO 17872:2019)
Peintures et vernis - Lignes directrices pour la Beschichtungsstoffe - Leitfaden zum Anbringen von
production de rayures au travers du revêtement de Ritzen durch eine Beschichtung auf Metallplatten für
panneaux métalliques en vue des essais de corrosion Korrosionsprüfungen (ISO 17872:2019)
(ISO 17872:2019)
This European Standard was approved by CEN on 5 August 2019.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this
European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references
concerning such national standards may be obtained on application to the CEN-CENELEC Management Centre or to any CEN
member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by
translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC Management
Centre has the same status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and
United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2019 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 17872:2019 E
worldwide for CEN national Members.
---------------------- Page: 3 ----------------------
SIST EN ISO 17872:2020
EN ISO 17872:2019 (E)
Contents Page
European foreword . 3
2
---------------------- Page: 4 ----------------------
SIST EN ISO 17872:2020
EN ISO 17872:2019 (E)
European foreword
This document (EN ISO 17872:2019) has been prepared by Technical Committee ISO/TC 35 "Paints and
varnishes" in collaboration with Technical Committee CEN/TC 139 “Paints and varnishes” 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 April 2020, and conflicting national standards shall be
withdrawn at the latest by April 2020.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN shall not be held responsible for identifying any or all such patent rights.
This document supersedes EN ISO 17872:2007.
According to the CEN-CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland,
Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Republic of
North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the
United Kingdom.
Endorsement notice
The text of ISO 17872:2019 has been approved by CEN as EN ISO 17872:2019 without any modification.
3
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SIST EN ISO 17872:2020
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SIST EN ISO 17872:2020
INTERNATIONAL ISO
STANDARD 17872
Second edition
2019-08
Paints and varnishes — Guidelines
for the introduction of scribe marks
through coatings on metallic panels
for corrosion testing
Peintures et vernis — Lignes directrices pour la production de rayures
au travers du revêtement de panneaux métalliques en vue des essais
de corrosion
Reference number
ISO 17872:2019(E)
©
ISO 2019
---------------------- Page: 7 ----------------------
SIST EN ISO 17872:2020
ISO 17872:2019(E)
COPYRIGHT PROTECTED DOCUMENT
© 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: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2019 – All rights reserved
---------------------- Page: 8 ----------------------
SIST EN ISO 17872:2020
ISO 17872:2019(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Scribe marks . 1
5 Apparatus . 5
6 Test panels . 6
7 Procedure. 6
8 Verification of the scribing tool . 6
9 Report . 6
Annex A (informative) Scribing tools . 8
Annex B (informative) Examples of possible different results in one corrosion test when
using different scribing tools.17
Bibliography .23
© ISO 2019 – All rights reserved iii
---------------------- Page: 9 ----------------------
SIST EN ISO 17872:2020
ISO 17872:2019(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 35, Paints and varnishes, Subcommittee
SC 9, General test methods for paints and varnishes.
This second edition cancels and replaces the first edition (ISO 17872:2007), which has been technically
revised. The main changes compared to the previous edition are as follows:
— Clause 2, "Normative references" and Clause 3, "Terms and definitions" have been added;
— figures of L-shaped and diagonal shaped scribes have been added;
— a second variation of the cross-sectional shape of U-shape scribe mark has been added in Figure 2;
— V-shape replaceable blade, disc milling cutter, graver and ceramic knife have been added to the list
of possible cutting tools;
— pictures of the cross sections have been added to the corresponding cutting tools;
— the examples for cutting tools in Table A.1 have been grouped to knife or blade tools, pencil type
tools and milling machines;
— the original Annex B has been replaced by a new annex on examples of possible different results in
one corrosion test when using different scribing tools.
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 2019 – All rights reserved
---------------------- Page: 10 ----------------------
SIST EN ISO 17872:2020
ISO 17872:2019(E)
Introduction
Many International Standards deal with corrosion testing, where scribe marks are introduced through
a coating to a metallic substrate. However, the method of scribe-mark introduction (scribing pattern,
tools, etc.) is not standardized across these standards.
The main purposes of an intentionally inflicted damage in a coating prior to corrosion testing are as
follows:
a) to simulate and to investigate how adhesion of a coating originating from an artificial damage after
exposure is ensured;
b) to obtain an accelerated response during a corrosion test, e.g. at quality control during production;
c) to investigate the general durability of a coating by observation of the rate of corrosion at a damage
spread after exposure.
Preliminary investigations have shown that several variants, both in terms of shape and dimensions, of
scribing tools are used. These variations occur both across countries and within countries. The effect of
using different tools is the production of scribe marks with different cross-sectional shape, depth and
exposed metal area. These differences will greatly affect test results obtained during corrosion tests, as
the intention of introducing scribe marks into a coating system is such that oxygen and the electrolyte
present during exposure testing can obtain access to a well-defined and active metal surface.
The actual method used to introduce a scribe mark depends on the coating type and thickness. However,
in all cases it is preferable if the cross-section is as smooth as possible, the metallic substrate is exposed
evenly and no coating remains on the exposed substrate.
© ISO 2019 – All rights reserved v
---------------------- Page: 11 ----------------------
SIST EN ISO 17872:2020
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SIST EN ISO 17872:2020
INTERNATIONAL STANDARD ISO 17872:2019(E)
Paints and varnishes — Guidelines for the introduction
of scribe marks through coatings on metallic panels for
corrosion testing
1 Scope
This document describes methods of scribing coated steel or test-pieces for corrosion tests, where the
coating system is applied at dry film thicknesses of less than 500 μm. It is intended as a guideline only,
being based on the results of a collaborative trial with no subsequent corrosion testing having been
carried out to determine the suitability of the introduced scribe marks for such tests.
This document covers the scribing of metallic panels or test pieces (chemically treated or not) made from:
— steel;
— galvanized steel;
— aluminium alloys;
— magnesium alloys.
It does not cover the scribing of electroplated metal or clad aluminium panels.
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 4618, Paints and varnishes — Terms and definitions
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4618 apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https: //www .iso .org/obp
— IEC Electropedia: available at http: //www .electropedia .org/
4 Scribe marks
Different scribe marks create different results depending on the used corrosion test.
The scribing method greatly affects how the corrosion process occurs and the reproducibility when
tests are repeated under the same conditions. Examples of possible different results in one corrosion
test when using different scribing tools are given in Annex B. In order to obtain results with high
accuracy and reproducibility, accurate and consistent scribing is required.
If not otherwise agreed or specified, a scribe mark is made as described in Figure 1a) to Figure 1e)
through the coating to the metal substrate according to the agreed conditions. For hot-dip galvanized
steel the scribe shall be cut completely through the paint coating and the metal layer and into the steel
substrate, as specified in ISO 12944-6 and ISO 12944-9.
© ISO 2019 – All rights reserved 1
---------------------- Page: 13 ----------------------
SIST EN ISO 17872:2020
ISO 17872:2019(E)
Typically, the suitable length of t
...
SLOVENSKI STANDARD
oSIST prEN ISO 17872:2018
01-oktober-2018
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]DSUHVNXãDQMHRGSRUQRVWLSURWLNRUR]LML ,62',6
Paints and varnishes - Guidelines for the introduction of scribe marks through coatings
on metallic panels for corrosion testing (ISO/DIS 17872:2018)
Beschichtungsstoffe - Leitfaden zum Anbringen von Ritzen durch eine Beschichtung auf
Metallplatten für Korrosionsprüfungen (ISO/DIS 17872:2018)
Peintures et vernis - Lignes directrices pour la production de rayures au travers du
revêtement de panneaux métalliques en vue des essais de corrosion (ISO/DIS
17872:2018)
Ta slovenski standard je istoveten z: prEN ISO 17872
ICS:
87.040 Barve in laki Paints and varnishes
oSIST prEN ISO 17872:2018 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
---------------------- Page: 1 ----------------------
oSIST prEN ISO 17872:2018
---------------------- Page: 2 ----------------------
oSIST prEN ISO 17872:2018
DRAFT INTERNATIONAL STANDARD
ISO/DIS 17872
ISO/TC 35/SC 9 Secretariat: BSI
Voting begins on: Voting terminates on:
2018-08-23 2018-11-15
Paints and varnishes — Guidelines for the introduction
of scribe marks through coatings on metallic panels for
corrosion testing
Peintures et vernis — Lignes directrices pour la production de rayures au travers du revêtement de
panneaux métalliques en vue des essais de corrosion
ICS: 87.040
THIS DOCUMENT IS A DRAFT CIRCULATED
This document is circulated as received from the committee secretariat.
FOR COMMENT AND APPROVAL. IT IS
THEREFORE SUBJECT TO CHANGE AND MAY
NOT BE REFERRED TO AS AN INTERNATIONAL
STANDARD UNTIL PUBLISHED AS SUCH.
IN ADDITION TO THEIR EVALUATION AS
ISO/CEN PARALLEL PROCESSING
BEING ACCEPTABLE FOR INDUSTRIAL,
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 17872:2018(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 2018
---------------------- Page: 3 ----------------------
oSIST prEN ISO 17872:2018
ISO/DIS 17872:2018(E)
COPYRIGHT PROTECTED DOCUMENT
© ISO 2018
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: +41 22 749 01 11
Fax: +41 22 749 09 47
Email: copyright@iso.org
Website: www.iso.org
Published in Switzerland
ii © ISO 2018 – All rights reserved
---------------------- Page: 4 ----------------------
oSIST prEN ISO 17872:2018
ISO/DIS 17872:2018(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Scribe marks . 1
5 Apparatus . 5
6 Test panels . 5
7 Procedure. 5
8 Verification of the scribing tool . 5
9 Report . 5
Annex A (informative) Scribing tools . 7
Annex B (informative) Examples of possible different results in one corrosion test when
using different scribing tools.17
Bibliography .22
© ISO 2018 – All rights reserved iii
---------------------- Page: 5 ----------------------
oSIST prEN ISO 17872:2018
ISO/DIS 17872:2018(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 35, Paints and varnishes, Subcommittee
SC 9, General test methods of paints and varnishes.
This second edition cancels and replaces the first edition (ISO 17872:2007), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— Clause 2 on "Normative references" and Clause 3 on "Terms and definitions" have been added;
— figures of L-shaped and diagonal shapped scribes have been added;
— a second variation of the cross-sectional shape of U-shape scribe mark has been added in Figure 2;
— V-shape replaceable blade, disc milling cutter, graver and ceramic knife have been added to the list
of possible cutting tools;
— pictures of the cross sections have benn added to the corresponding cutting tools;
— the examples for cutting tools in Table A.1 have been grouped to knife or blade tools, pencil type
tools and milling machines;
— the original Annex B has been replaced by a new annex on examples of possible different results in
one corrosion test when using different scribing tools.
iv © ISO 2018 – All rights reserved
---------------------- Page: 6 ----------------------
oSIST prEN ISO 17872:2018
ISO/DIS 17872:2018(E)
Introduction
Many International Standards deal with corrosion testing, where scribe marks are introduced through
a coating to a metallic substrate. However, the method of scribe-mark introduction (scribing pattern,
tools, etc.) is not standardized across these standards.
The main purposes of an intentionally inflicted damage in a coating prior to corrosion testing are as
follows:
a) to simulate and to investigate how adhesion of a coating originating from an artificial damage after
exposure is ensured;
b) to obtain an accelerated response during a corrosion test, e.g. at quality control during production;
c) to investigate the general durability of a coating by observation of the rate of corrosion at a damage
spread after exposure.
Preliminary investigations have shown that several variants, both in terms of shape and dimensions, of
scribing tools are used. This variation occurs both across countries and within countries. The effect of
using different tools is the production of scribe marks with different cross-sectional shape, depth and
exposed metal area. These differences will greatly affect test results obtained during corrosion tests, as
the intention of introducing scribe marks into a coating system is such that oxygen and the electrolyte
present during exposure testing can obtain access to a well-defined and active metal surface.
The actual method used to introduce a scribe mark depends on the coating type and thickness. However,
in all cases it is preferable if the cross-section is as smooth as possible, the metallic substrate is exposed
evenly and no coating remains on the exposed substrate.
© ISO 2018 – All rights reserved v
---------------------- Page: 7 ----------------------
oSIST prEN ISO 17872:2018
---------------------- Page: 8 ----------------------
oSIST prEN ISO 17872:2018
DRAFT INTERNATIONAL STANDARD ISO/DIS 17872:2018(E)
Paints and varnishes — Guidelines for the introduction
of scribe marks through coatings on metallic panels for
corrosion testing
1 Scope
This document describes methods of scribing coated steel or test-pieces for corrosion tests, where the
coating system is applied at dry film thicknesses of less than 500 μm. It is intended as a guideline only,
being based on the results of a collaborative trial with no subsequent corrosion testing having been
carried out to determine the suitability of the introduced scribe marks for such tests.
This document covers the scribing of metallic panels or test pieces (chemically treated or not) made from:
— steel,
— galvanized steel,
— aluminium alloys,
— magnesium alloys.
It does not cover the scribing of electroplated metal or clad aluminium panels.
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 4618, Paints and varnishes — Terms and definitions
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 4618 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 http: //www .iso .org/obp
4 Scribe marks
Different scribe marks create different results depending on the used corrosion test.
The scribing method greatly affects how the corrosion process occurs and the reproducibility when
tests are repeated under the same conditions. In order to obtain results with high accuracy and
reproducibility, accurate and consistent scribing is required.
If not otherwise agreed or specified, a scribe mark is made as described in Figure 1a) to e) through the
coating to the metal substrate according to the agreed conditions. Typically, the suitable length of the
scribed lines is in the range of 50 mm to 70 mm, depending on the coating thickness and the expected
amount of corrosion.
© ISO 2018 – All rights reserved 1
---------------------- Page: 9 ----------------------
oSIST prEN ISO 17872:2018
ISO/DIS 17872:2018(E)
The length of the scribe mark should be significantly more than the expected creep resulting from the
corrosion test carried out. It should give an overview what happens on the surface of the system. Too
short scribing lengths have an impact on the results.
The width of the scribe mark can also affect the result of a corrosion test. The smaller the width, the
stronger is the tendency for the exposed metal surface to be passivated by deposition of sparingly
soluble corrosion products. Kind and thickness of an organic coating can have an impact to the scribing
line in that way that the scribing line closes itself partially in kind of a capillary. Therefore no or less
electrolytes and/or oxygen could reach the metal surface.It is therefore important to select a scribing
tool which will provide a suitable scribe width for the corrosion test being carried out.
The orientation of the scribed lines is often significant in terms of affecting corrosion test results.
On panels with a slight inclination from the vertical, e.g. for salt-spray tests, more salt is collected in
a horizontally exposed scribe mark. Also, a horizontally exposed scribe mark will generate an even
salt distribution, whereas a diagonal, or more particularly a vertical, scribe mark tends to generate
a gradient, with an increasing amount of salt along the lower edge of the scribe mark. An increased
amount of salt usually leads to an increased corrosion rate, but on coated steel, high salt concentration
might have an inhibiting effect on corrosion since the formed corrosion products are very dense.
Milled/rolled aluminium substrates shall get basically two scribes in different orientations to consider
the influence of the milling/rolling direction to the corrosion result.
The cross-section of the scribe mark should be as uniform as possible along its entire length. The
coating should be cut smoothly along the direction of the scribe mark. The cross-sectional shape of
the scribe may be either “V” or “U” shaped, depending upon the tool used, and should be such that for
a “V”-shaped cut a > b > c and for a “U”-shaped cut a > b, with the width (b) of both “V” and “U” shapes
such that b > 0,2 mm (see Figure 2 for an explanation of the symbols). Certain scribing tools may also
produce a rectangular cross-section, where a, b and c are approximately equal (one example is the "U"-
shaped cut variation 2).
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