SIST EN ISO 26423:2016
(Main)Fine ceramics (advanced ceramics, advanced technical ceramics) - Determination of coating thickness by crater-grinding method (ISO 26423:2009)
Fine ceramics (advanced ceramics, advanced technical ceramics) - Determination of coating thickness by crater-grinding method (ISO 26423:2009)
This International Standard specifies a method for the determination of the thickness of ceramic coatings by a crater-grinding method, which includes the grinding of a spherical cavity and subsequent microscopic examination of the crater.
Because of the uncertainty introduced into the measurement of crater dimensions, the test is not suitable for use where the surface roughness of the coating and/or substrate exceeds 20 % of the coating thickness.
Hochleistungskeramik - Bestimmung der Schichtdicke mit dem Kalottenschleifverfahren (ISO 26423:2009)
Diese Internationale Norm legt ein Verfahren zur Bestimmung der Dicke von keramischen Beschichtungen mit einem Kalottenschleifverfahren fest, bei dem eine sphärische Vertiefung geschliffen und anschließend die Kalotte mikroskopisch untersucht wird.
Infolge der sich bei der Messung der Kalottenmaße ergebenden Unsicherheit ist diese Prüfung nicht für Anwendungen geeignet, bei denen die Oberflächenrauheit der Beschichtung und/oder des Grundwerkstoffes 20 % der Schichtdicke überschreitet.
ANMERKUNG Ein alternatives Verfahren zur Bestimmung der Dicke mit einem Kontaktprofilometer ist in ISO 18452 angegeben.
Céramiques techniques - Détermination de l'épaisseur de revêtement par la méthode de meulage de cratère (ISO 26423:2009)
L'ISO 26423:2009 spécifie une méthode permettant de déterminer l'épaisseur de revêtements céramiques par une méthode de meulage d'un cratère qui comprend l'obtention par abrasion d'une cavité sphérique suivie d'un examen microscopique du cratère.
En raison de l'incertitude introduite dans le mesurage des dimensions du cratère, l'essai n'est pas approprié lorsque la rugosité de la surface du revêtement et/ou du substrat dépasse 20 % de l'épaisseur du revêtement.
Fina keramika (sodobna keramika, sodobna tehnična keramika) - Ugotavljanje gostote premaza z metodo čelnega brušenja (ISO 26423:2009)
Ta mednarodni standard opredeljuje metodo za določanje debeline keramičnih prevlek z metodo čelnega brušenja, ki zajema brušenje okrogle vdolbine in nato pregled kraterja pod mikroskopom. Zaradi negotovosti, do katere pride pri merjenju kraterja, preskus ni primeren za uporabo v primerih, ko površinska hrapavost prevleke in/ali substrata presega 20 % debeline prevleke.
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN ISO 26423:2016
01-junij-2016
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SIST EN 1071-2:2004
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JRVWRWHSUHPD]D]PHWRGRþHOQHJDEUXãHQMD ,62
Fine ceramics (advanced ceramics, advanced technical ceramics) - Determination of
coating thickness by crater-grinding method (ISO 26423:2009)
Hochleistungskeramik - Bestimmung der Schichtdicke mit dem Kalottenschleifverfahren
(ISO 26423:2009)
Céramiques techniques - Détermination de l'épaisseur de revêtement par la méthode de
meulage de cratère (ISO 26423:2009)
Ta slovenski standard je istoveten z: EN ISO 26423:2016
ICS:
25.220.99 Druge obdelave in prevleke Other treatments and
coatings
81.060.30 Sodobna keramika Advanced ceramics
SIST EN ISO 26423:2016 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN ISO 26423:2016
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SIST EN ISO 26423:2016
EN ISO 26423
EUROPEAN STANDARD
NORME EUROPÉENNE
April 2016
EUROPÄISCHE NORM
ICS 81.060.30 Supersedes EN 1071-2:2002
English Version
Fine ceramics (advanced ceramics, advanced technical
ceramics) - Determination of coating thickness by crater-
grinding method (ISO 26423:2009)
Céramiques techniques - Détermination de l'épaisseur Hochleistungskeramik - Bestimmung der Schichtdicke
de revêtement par la méthode de meulage de cratère mit dem Kalottenschleifverfahren (ISO 26423:2009)
(ISO 26423:2009)
This European Standard was approved by CEN on 25 March 2016.
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, 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: Avenue Marnix 17, B-1000 Brussels
© 2016 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN ISO 26423:2016 E
worldwide for CEN national Members.
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SIST EN ISO 26423:2016
EN ISO 26423:2016 (E)
Contents Page
European foreword . 3
2
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SIST EN ISO 26423:2016
EN ISO 26423:2016 (E)
European foreword
The text of ISO 26423:2009 has been prepared by Technical Committee ISO/TC 206 “Fine ceramics” of
the International Organization for Standardization (ISO) and has been taken over as EN ISO 26423:2016
by Technical Committee CEN/TC 184 “Advanced technical ceramics” 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 October 2016, and conflicting national standards shall
be withdrawn at the latest by October 2016.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
This document supersedes EN 1071-2:2002.
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, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Turkey and the United Kingdom.
Endorsement notice
The text of ISO 26423:2009 has been approved by CEN as EN ISO 26423:2016 without any modification.
3
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SIST EN ISO 26423:2016
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SIST EN ISO 26423:2016
INTERNATIONAL ISO
STANDARD 26423
First edition
2009-01-15
Fine ceramics (advanced ceramics,
advanced technical ceramics) —
Determination of coating thickness by
crater-grinding method
Céramiques techniques — Détermination de l'épaisseur de revêtement
par la méthode de meulage de cratère
Reference number
ISO 26423:2009(E)
©
ISO 2009
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SIST EN ISO 26423:2016
ISO 26423:2009(E)
PDF disclaimer
This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but
shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In
downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat
accepts no liability in this area.
Adobe is a trademark of Adobe Systems Incorporated.
Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation
parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In
the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.
COPYRIGHT PROTECTED DOCUMENT
© ISO 2009
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means,
electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or
ISO's member body in the country of the requester.
ISO copyright office
Case postale 56 • CH-1211 Geneva 20
Tel. + 41 22 749 01 11
Fax + 41 22 749 09 47
E-mail copyright@iso.org
Web www.iso.org
Published in Switzerland
ii © ISO 2009 – All rights reserved
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SIST EN ISO 26423:2016
ISO 26423:2009(E)
Contents Page
Foreword. iv
1 Scope . 1
2 Normative references . 1
3 Symbols . 1
4 Principle. 3
5 Sampling. 3
6 Test procedure . 3
6.1 General. 3
6.2 Preparation for the test . 4
6.3 Test parameters . 4
6.4 Example of test parameters. 5
7 Microscopic examination and measurement. 5
7.1 Examination. 5
7.2 Measurement. 5
8 Calculations. 6
9 Uncertainty and sources of error. 7
10 Test report . 7
Annex A (informative) Errors associated with using different formulae for calculating film
thickness . 9
Annex B (informative) Estimating measurement uncertainty and errors. 12
Bibliography . 15
© ISO 2009 – All rights reserved iii
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SIST EN ISO 26423:2016
ISO 26423:2009(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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
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.
ISO 26423 was prepared by Technical Committee ISO/TC 206, Fine ceramics.
iv © ISO 2009 – All rights reserved
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SIST EN ISO 26423:2016
INTERNATIONAL STANDARD ISO 26423:2009(E)
Fine ceramics (advanced ceramics, advanced technical
ceramics) — Determination of coating thickness by crater-
grinding method
1 Scope
This International Standard specifies a method for the determination of the thickness of ceramic coatings by a
crater-grinding method, which includes the grinding of a spherical cavity and subsequent microscopic
examination of the crater.
Because of the uncertainty introduced into the measurement of crater dimensions, the test is not suitable for
use where the surface roughness of the coating and/or substrate exceeds 20 % of the coating thickness.
NOTE An alternative method for measurement of thickness, using a contact probe profilometer, is given in
ISO 18452.
2 Normative references
The following referenced documents are indispensable for the application 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 3290-1, Rolling bearings — Balls — Part 1: Steel balls
ISO/IEC 17025:2005, General requirements for the competence of testing and calibration laboratories
3 Symbols
For the purpose of this document, the following symbols apply.
D best estimate of the outer diameter of the crater, at the surface of the coating, in micrometres (see
Figure 1);
d best estimate of the inner diameter of the crater, defined by the bottom of the coating layer, in
micrometres (see Figure 1);
h thickness of the coating, in micrometres (see Figure 1);
m subscript indicating mean value (D , d , X , Y ).
m m m m
r radius of the ball, in micrometres (see Figure 1);
b
r radius of curvature of specimen;
s
l total penetration depth of the ball, in micrometres (see Figure 1);
T
l penetration depth of the ball in the substrate, in micrometres (see Figure 1);
t
© ISO 2009 – All rights reserved 1
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SIST EN ISO 26423:2016
ISO 26423:2009(E)
X distance, on a coplanar projection of the two craters, between the periphery of the outer crater and a
diametrically equivalent point on the same side of the inner crater, in micrometres (see Figure 1);
Y distance, on a coplanar projection of the two craters, between the periphery of the outer crater and a
diametrically equivalent point on the opposite side of the inner crater, in micrometres (see Figure 1).
Key
1 coating
2 substrate
Figure 1 — Principal dimensions used in the test method
2 © ISO 2009 – All rights reserved
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SIST EN ISO 26423:2016
ISO 26423:2009(E)
4 Principle
Coating thickness often plays a major role in the performance of coated tools and machine parts. Many
different techniques have been developed for assessing the coating thickness. Among these, the crater-
grinding method and the step height method (see ISO 18452) are easy to perform and applicable to most
coated systems.
The method is simple and straightforward. A crater is ground into the coated part by means of a rotating ball
wetted by an abrasive slurry. The thickness of the coating is derived from the ball and crater dimensional
characteristics. Contrast between the different materials constituting the coating and substrate is a
prerequisite for the method, to enable detection of the interface between the coating and the surface.
Test specimens should be either flat or cylindrical. Flatness can be considered as sufficient if the local
specimen radius of curvature, r , satisfies the relation r > 100 × r (for error u 1 %).
s s b
5 Sampling
A representative test specimen of the product under test shall be used. Test pieces shall be coated original
items or, where this is not possible, items made in the same way as the batch to be tested. For large parts,
separate manufacturing of the test piece may be necessary.
6 Test procedure
6.1 General
A ball wetted by an abrasive slurry is rotated against the surface of the test piece. A spherical wear crater is
produced, and the test is finished when the depth of penetration of the spherical crater is greater than the
coating thickness. The coating thickness is then derived from the dimensions of the wear scars (full crater and
substrate crater diameters) and the ball diameter.
Different test rig set-ups may be used. The ball can be rotated freely on a drive shaft, whereby its mass is
used to produce the contact load, or it may be clamped in the drive axis while the specimen is loaded by
means of a lever system. A typical arrangement is shown in Figure 2.
Alternatively, a wheel instead of a ball may be used, in which case the sample shall also
...
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.WDYOMDQMHHochleistungskeramik - Bestimmung der Schichtdicke mit dem Kalottenschleifverfahren (ISO 26423:2009)Céramiques techniques - Détermination de l'épaisseur de revêtement par la méthode de meulage de cratère (ISO 26423:2009)Fine ceramics (advanced ceramics, advanced technical ceramics) - Determination of coating thickness by crater-grinding method (ISO 26423:2009)81.060.30Sodobna keramikaAdvanced ceramics25.220.99Druge obdelave in prevlekeOther treatments and coatingsICS:Ta slovenski standard je istoveten z:FprEN ISO 26423kSIST FprEN ISO 26423:2015en01-november-2015kSIST FprEN ISO 26423:2015SLOVENSKI
STANDARD
kSIST FprEN ISO 26423:2015
EUROPEAN STANDARD NORME EUROPÉENNE EUROPÄISCHE NORM
FINAL DRAFT
FprEN ISO 26423
September
t r s w ICS
z sä r x rä u r Will supersede EN
s r y sæ tã t r r tEnglish Version
Céramiques techniques æ Détermination de l 5épaisseur de revêtement par la méthode de meulage de cratère
Hochleistungskeramik æ Bestimmung der Schichtdicke This draft European Standard is submitted to CEN members for unique acceptance procedureä It has been drawn up by the
If this draft becomes a European Standardá CEN members are bounwhich stipulate the conditions for giving this European Standard the status of a national standard without any alterationä
This draft European Standard was established by CEN in three ofer language made by translation under the responsibility of a CEN member into its own language and notified to the CENæCENELEC Management Centre has the same status as the official versionsä
CEN members are the national standards bodies of Austriaá Belgiumá Bulgariaá Croatiaá Cyprusá Czech Republicá Denmarká Estoniaá Finlandá Former Yugoslav Republic of Macedoniaá Franceá Germanyá Greeceá Hungaryá Icelandá Irelandá Italyá Latviaá Lithuaniaá Luxembourgá Maltaá Netherlandsá Norwayá Polandá Portugalá Romaniaá Slovakiaá Sloveniaá Spainá Swedená Switzerlandá Turkey and United Kingdomä
Recipients of this draft are invited to submitá with their commentsá notification of any relevant patent rights of which they are aware and to provide supporting documentationä
Warning ã This document is not a European Standardä It is distributed for review and commentsä It is subject to change without notice and shall not be referred to as a European Standardä
EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG
CEN-CENELEC Management Centre:
Avenue Marnix 17,
B-1000 Brussels
9
t r s w CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Membersä Refä Noä FprEN ISO
t x v t uã t r s w EkSIST FprEN ISO 26423:2015
FprEN ISO 26423:2015 (E) 2 Contents
Page European foreword . 3
kSIST FprEN ISO 26423:2015
FprEN ISO 26423:2015 (E) 3 European foreword The text of ISO 26423:2009 has been prepared by Technical Committee ISO/TC 206 “Fine ceramics” of the International Organization for Standardization (ISO) and has been taken over as FprEN ISO 26423:2015 by Technical Committee CEN/TC 184 “Advanced technical ceramics” the secretariat of which is held by DIN. This document is currently submitted to the Unique Acceptance Procedure. This document will supersede EN 1071-2:2002. Endorsement notice The text of ISO 26423:2009 has been approved by CEN as FprEN ISO 26423:2015 without any modification. kSIST FprEN ISO 26423:2015
kSIST FprEN ISO 26423:2015
Reference numberISO 26423:2009(E)© ISO 2009
INTERNATIONAL STANDARD ISO26423First edition2009-01-15Fine ceramics (advanced ceramics, advanced technical ceramics) — Determination of coating thickness by crater-grinding method Céramiques techniques — Détermination de l'épaisseur de revêtement par la méthode de meulage de cratère
kSIST FprEN ISO 26423:2015
ISO 26423:2009(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobe's licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobe's licensing policy. The ISO Central Secretariat accepts no liability in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitable for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below.
COPYRIGHT PROTECTED DOCUMENT
©
ISO 2009 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISO's member body in the country of the requester. ISO copyright office Case postale 56 • CH-1211 Geneva 20 Tel.
+ 41 22 749 01 11 Fax
+ 41 22 749 09 47 E-mail
copyright@iso.org Web
www.iso.org Published in Switzerland
ii © ISO 2009 – All rights reserved
kSIST FprEN ISO 26423:2015
ISO 26423:2009(E) © ISO 2009 – All rights reserved iiiContents Page Foreword.iv 1 Scope.1 2 Normative references.1 3 Symbols.1 4 Principle.3 5 Sampling.3 6 Test procedure.3 6.1 General.3 6.2 Preparation for the test.4 6.3 Test parameters.4 6.4 Example of test parameters.5 7 Microscopic examination and measurement.5 7.1 Examination.5 7.2 Measurement.5 8 Calculations.6 9 Uncertainty and sources of error.7 10 Test report.7 Annex A (informative)
Errors associated with using different formulae for calculating film thickness.9 Annex B (informative)
Estimating measurement uncertainty and errors.12 Bibliography.15
kSIST FprEN ISO 26423:2015
ISO 26423:2009(E) iv © ISO 2009 – All rights reserved 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. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. 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. ISO 26423 was prepared by Technical Committee ISO/TC 206, Fine ceramics.
kSIST FprEN ISO 26423:2015
INTERNATIONAL STANDARD ISO 26423:2009(E) © ISO 2009 – All rights reserved 1Fine ceramics (advanced ceramics, advanced technical ceramics) — Determination of coating thickness by crater-grinding method 1 Scope This International Standard specifies a method for the determination of the thickness of ceramic coatings by a crater-grinding method, which includes the grinding of a spherical cavity and subsequent microscopic examination of the crater. Because of the uncertainty introduced into the measurement of crater dimensions, the test is not suitable for use where the surface roughness of the coating and/or substrate exceeds 20 % of the coating thickness. NOTE An alternative method for measurement of thickness, using a contact probe profilometer, is given in ISO 18452. 2 Normative references The following referenced documents are indispensable for the application 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 3290-1, Rolling bearings — Balls — Part 1: Steel balls ISO/IEC 17025:2005, General requirements for the competence of testing and calibration laboratories 3 Symbols For the purpose of this document, the following symbols apply. D best estimate of the outer diameter of the crater, at the surface of the coating, in micrometres (see Figure 1); d best estimate of the inner diameter of the crater, defined by the bottom of the coating layer, in micrometres (see Figure 1); h thickness of the coating, in micrometres (see Figure 1); m subscript indicating mean value (Dm, dm, Xm, Ym). rb radius of the ball, in micrometres (see Figure 1); rs radius of curvature of specimen; lT total penetration depth of the ball, in micrometres (see Figure 1); lt penetration depth of the ball in the substrate, in micrometres (see Figure 1); kSIST FprEN ISO 26423:2015
ISO 26423:2009(E) 2 © ISO 2009 – All rights reserved X distance, on a coplanar projection of the two craters, between the periphery of the outer crater and a diametrically equivalent point on the same side of the inner crater, in micrometres (see Figure 1); Y distance, on a coplanar projection of the two craters, between the periphery of the outer crater and a diametrically equivalent point on the opposite side of the inner crater, in micrometres (see Figure 1).
Key 1 coating 2 substrate Figure 1 — Principal dimensions used in the test method
kSIST FprEN ISO 26423:2015
ISO 26423:2009(E) © ISO 2009 – All rights reserved 34 Principle Coating thickness often plays a major role in the performance of coated tools and machine parts. Many different techniques have been developed for assessing the coating thickness. Among these, the crater-grinding method and the step height method (see ISO 18452) are easy to perform and applicable to most coated systems. The method is simple and straightforward. A crater is ground into the coated part by means of a rotating ball wetted by an abrasive slurry. The thickness of the coating is derived from the ball and crater dimensional characteristics. Contrast between the different materials constituting the coating and substrate is a prerequisite for the method, to enable detection of the interface between the coating and the surface. Test specimens should be either flat or cylindrical. Flatness can be considered as sufficient if the local specimen radius of curvature, rs, satisfies the relation rs > 100 × rb (for error u 1 %). 5 Sampling A representative test specimen of the product under test shall be used. Test pieces shall be coated original items or, where this is not possible, items made in the same way as the batch to be tested. For large parts, separate manufacturing of the test piece may be necessary. 6 Test procedure 6.1 General A ball wetted by an abrasive slurry is rotated against the surface of the test piece. A spherical wear crater is produced, and the test is finished when the depth of penetration of the spherical crater is greater than the coating thickness. The coating thickness is then derived from the dimensions of the wear scars (full crater and substrate crater diameters) and the ball diameter. Different test rig set-ups may be used. The ball can be rotated freely on a drive shaft, whereby its mass is used to produce the contact load, or it may be clamped in the drive axis while the specimen is loaded by means of a lever system. A typical arrangement is shown in Figure 2. Alternatively, a wheel instead of a ball may be used, in which case the sample shall also be rotated (this is the same principle as used with dimple grinders for the preparation of TEM specimens). Different abrasives (e.g. diamond, alumina, silica) can be used, and commercially available suspensions based on alcohol, oil or water may be applied. The abrasive slurry may be smeared onto
...
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