1、BS EN ISO 14604:2016Fine ceramics (advancedceramics, advanced technicalceramics) Methods oftest for ceramic coatings Determination of fracturestrain (ISO 14604:2012)BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS EN ISO 14604:2016 BRITISH STANDARDNational foreword
2、This British Standard is the UK implementation of EN ISO 14604:2016.The UK participation in its preparation was entrusted to TechnicalCommittee RPI/13, Advanced technical ceramics.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does n
3、ot purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2016. Published by BSI StandardsLimited 2016ISBN 978 0 580 91167 5ICS 81.060.30Compliance with a British Standard cannot confer immunity fromlegal obli
4、gations.This British Standard was published under the authority of theStandards Policy and Strategy Committee on 31 December 2012.Amendments/corrigenda issued since publicationDate Text affected31 August 2016 This corrigendum renumbers BS ISO 14604:2012as BS EN ISO 14604:2016It is identical to ISO 1
5、4604:2012. It supersedes BS EN 1071-9:2009 and BS ISO 14604:2012 which are withdrawn.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 14604 April 2016 ICS 81.060.30 Supersedes EN 1071-9:2009English Version Fine ceramics (advanced ceramics, advanced technical ceramics) - Methods of test for c
6、eramic coatings - Determination of fracture strain (ISO 14604:2012) Cramiques techniques - Mthodes dessai des revtements cramiques - Dtermination de la dformation la rupture (ISO 14604:2012) Hochleistungskeramik - Verfahren zur Prfung keramischer Schichten - Bestimmung der Bruchdehnung (ISO 14604:20
7、12) 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 r
8、eferences 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
9、 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 Maced
10、onia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROP
11、ISCHES KOMITEE FR 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 worldwide for CEN national Members. Ref. No. EN ISO 14604:2016 E3 European foreword The text of ISO 14604:2012 has been prepared by Tec
12、hnical Committee ISO/TC 206 “Fine ceramics” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 14604:2016 by Technical Committee CEN/TC 184 “Advanced technical ceramics” the secretariat of which is held by DIN. This European Standard shall be given the stat
13、us 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 sub
14、ject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN 1071-9:2009. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement th
15、is 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, Slovak
16、ia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 14604:2012 has been approved by CEN as EN ISO 14604:2016 without any modification. BS EN ISO 14604:2016 EN ISO 14604:2016 (E) ISO 2012 All rights reserved iiiContents PageForeword ivIntroducti
17、on v1 Scope . 12 Normative references 13 Terms and definitions . 14 Significance and use 25 Principle 26 Apparatus and materials 26.1 Instrumentation . 26.2 Specimen preparation 37 Test procedure 47.1 Calibration 47.2 Sample loading 47.3 Strain determination 47.4 Crack detection . 57.5 Test paramete
18、rs 68 Test report . 6Bibliography .11BS EN ISO 14604:2016 ISO 14604:2012 (E)ForewordISO (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 t
19、echnical 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 clos
20、ely 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
21、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
22、 may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.ISO 14604 was prepared by Technical Committee ISO/TC 206, Fine ceramics.iv ISO 2012 All rights reservedBS EN ISO 14604:2016 ISO 14604:2012 (E)IntroductionThe fracture strain of a coa
23、ting is a critical factor often determining the performance of a coated product. Clearly, if stressed either directly or due to thermal effects (thermal expansion coefficient mismatch between the coating and substrate) coating cracking can occur if the critical fracture stress/strain is exceeded, an
24、d in many cases the effectiveness of the coating will be reduced. For example, corrosion-resistant coatings loose their protective character if cracking occurs, and optical coatings become ineffective when cracked. In many cases, cracking is the first stage of a much more serious form of failure in
25、which large areas of the coating can spall.This International Standard describes a method for the determination of fracture strain using a technique of applying stresses to a coupon of material by a uniaxial tensile or compressive test or a beam bending test where the initiation of fracture in the c
26、oating is determined using an acoustic emission method.The extent to which coated components can withstand external applied loads is an important property in the application of any coated system, and usually the failure stress is required. For calculation of the stress, both the fracture strain and
27、Youngs modulus of the coating should be known. ISO 14577-4:20071can be used to measure Youngs modulus by depth-sensing indentation, but there are other methods involving flexure and impact excitation that may also be applied (References 2, 3). ISO 2012 All rights reserved vBS EN ISO 14604:2016 ISO 1
28、4604:2012 (E)BS EN ISO 14604:2016 ISO 14604:2012 (E)Fine ceramics (advanced ceramics, advanced technical ceramics) Methods of test for ceramic coatings Determination of fracture strain1 ScopeThis International Standard describes a method of measuring the fracture strain of ceramic coatings by means
29、of uniaxial tension or compression tests coupled with acoustic emission to monitor the onset of cracking of the coating. Tensile or compressive strains can also be applied by flexure using four-point bending. Measurements can be made in favourable cases at elevated temperatures as well as at room te
30、mperature.2 Normative referencesThe 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.EN 10002-1, Metall
31、ic materials Tensile testing Part 1: Method of test at ambient temperatureEN 10002-5, Metallic materials Tensile testing Part 5: Method of test at elevated temperatureISO 12106, Metallic materials Fatigue testing Axial-strain-controlled method3 Terms and definitionsFor the purposes of this document,
32、 the following terms and definitions apply.3.1fracture strainstrain required to create a detectable crack in the coatingNOTE The presence of the crack can be detected using optical or scanning electron microscopy, or indirectly using acoustic emission3.2acoustic emissionAEgeneration of acoustic sign
33、alsNOTE See Figure 1 for definition of AE signals. AE signals are recorded as hits, counts, energy or amplitude (3.3, 3.4, 3.5 and 3.6).3.3AE hitsingle acoustic event above a set threshold3.4AE energyarea of the waveform of an AE hit3.5AE amplitudepeak of the waveform of an AE hitINTERNATIONAL STAND
34、ARD ISO 2012 All rights reserved 1BS EN ISO 14604:2016 ISO 14604:2012 (E)3.6AE thresholdarbitrary AE amplitude at which AE hits are deemed to be significant and above the AE signals generated by the test equipment3.7AE countsnumber of times the AE waveform passes a set threshold within a single hit3
35、.8waveguidemetallic wire connecting (usually by spot welding) the sample to the AE transducer4 Significance and useThis test procedure covers the measurement of fracture strain in tension or compression in coatings subject to mechanical stress at ambient or elevated temperature.The method is applica
36、ble to cases where the substrate is sufficiently ductile such that fracture of the coating occurs before the substrate. In addition, if during plastic deformation of the substrate acoustic signals are generated, this may interfere with those caused by coating fracture. Where possible, it is recommen
37、ded that a test be carried out with the uncoated substrate to determine whether such extraneous AE signals occur.5 PrincipleSpecimens of appropriate geometry are submitted to a mechanical stress; the subsequent strain is measured and the onset of coating failure is detected. The test draws upon the
38、expertise of standard tensile and compressive tests but requires additional care due to the precision required of the measurements. The applied stress may be tensile or compressive and may be applied directly or in flexure. The test shall be carried out to satisfy the requirements of accepted standa
39、rds for mechanical testing of materials under the selected method of loading.NOTE 1 Detection of the fracture of coatings can be carried out in a number of ways. The most convenient is to use acoustic emission (AE), which allows continuous monitoring of the specimen. Acoustic signals are produced wh
40、en a crack forms. These signals are captured using suitable detectors and the signals generated are then analysed. In many cases, a waveguide is used to carry the signal from the specimen to the detector; this waveguide is normally a metallic material. Use of two AE detectors can help to eliminate e
41、xtraneous signals coming from the loading mechanism. Commercially available AE systems can be used for this work.NOTE 2 Where AE cannot be used, crack detection is possible by high-resolution video systems, which may allow continuous monitoring. Alternatively, optical or scanning electron microscopy
42、 can be used to examine the samples. Normally this is done post-test, but in situ examination is also possible.6 Apparatus and materials6.1 Instrumentation6.1.1 In simplest terms, the equipment required is a mechanism to apply load to the specimen; extensometry to measure the strain; and apparatus t
43、o detect/monitor fracture of the surface layer. Load is normally applied continuously through servo-electric testing machines; the load capacity of the frame should be sufficient to allow straining of the specimen to beyond the yield point of the substrate material. Continuation of the test to compl
44、ete separation of the specimen is not normally required.6.1.2 For flexural testing, a suitable test jig is required; four-point bending is recommended as this applies more uniform bending moment over the gauge length. A suitable jig is shown in Figure 2.2 ISO 2012 All rights reservedBS EN ISO 14604:
45、2016 ISO 14604:2012 (E)6.1.3 Extensometry should be sufficiently precise to measure strain at a resolution of 0,01 %.6.1.4 For tests at high temperatures using the uniaxial test configuration, a furnace is required which allows access for attachment of load frame, together with extensometry, thermoc
46、ouples and waveguides to transmit the AE signals to the AE detector(s). For the four-point bend configuration, an oxidation-resistant jig shall be used.NOTE Deformation of oxide layers formed on a metallic jig will probably contribute to AE signals during the test.6.1.5 Crack detection in the coatin
47、g may be performed visually or by monitoring AE. Visual inspection requires suitable long-focal-length video facilities with a field of view containing the gauge length. At high temperatures, the availability of a cool path to the video camera is also required to avoid shimmer of the image.6.2 Speci
48、men preparation6.2.1 Standard specimens shall be used as appropriate for the uniaxial or flexure test configurations; for uniaxial tensile tests the specimen shapes are defined in EN 10002-1, for compression tests in ISO 12106 and, for flexure, simple bar-shaped samples of appropriate thickness can
49、be used. The coating may be deposited on to the sample after machining to the required shape, or in the case of flat specimens, the test piece can be machined from the coated material. In the latter case, care shall be taken to avoid damage to the test region that may cause premature fracture. Generally, the surface of the coating should not be ground or polished except where there is a requirement to do so.6.2.2 The strain that is measured using this technique represents a summation of the inherent fracture strain of the surf
