EN ISO 4499-4-2016 en Hardmetals - Metallographic determination of microstructure - Part 4 Characterisation of porosity carbon defects and eta-phase content《硬质合金显微组织的金相测定第4部分 表征孔隙率.pdf

1、BSI Standards PublicationBS EN ISO 4499-4:2016Hardmetals Metallographicdetermination ofmicrostructurePart 4: Characterisation of porosity, carbondefects and eta-phase contentBS EN ISO 4499-4:2016 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO4499-4:2016. It

2、 supersedes BS EN 24505:1993 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee ISE/65, Sintered metal components.A list of organizations represented on this committee can beobtained on request to its secretary.This publication does not purport to include

3、all the necessaryprovisions of a contract. Users are responsible for its correctapplication. The British Standards Institution 2016.Published by BSI Standards Limited 2016ISBN 978 0 580 81470 9ICS 77.040.99; 77.160Compliance with a British Standard cannot confer immunity fromlegal obligations.This B

4、ritish Standard was published under the authority of theStandards Policy and Strategy Committee on 31 March 2016.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 4499-4 March 2016 ICS 77.040.99; 77.160 Supersedes EN 24

5、505:1993English Version Hardmetals - Metallographic determination of microstructure - Part 4: Characterisation of porosity, carbon defects and eta-phase content (ISO 4499-4:2016)Mtaux-durs - Dtermination mtallographique de la microstructure - Partie 4: Caractrisation de la porosit, des dfauts carbon

6、e et de la teneur en phase ta (ISO 4499-4:2016) Hartmetalle - Metallographische Bestimmung der Mikrostruktur - Teil 4: Charakterisierung von Porositt, Kohlenstofffehlern und Anteil an Eta-Phase (ISO 4499-4:2016) This European Standard was approved by CEN on 4 February 2016. CEN members are bound to

7、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-CEN

8、ELEC 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 th

9、e 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, Luxemb

10、ourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

11、 2016 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 4499-4:2016 EBS EN ISO 4499-4:2016EN ISO 4499-4:2016 (E) 3 European foreword This document (EN ISO 4499-4:2016) has been prepared by Technical Committee ISO/TC 119 “Powder m

12、etallurgy“. 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 September 2016, and conflicting national standards shall be withdrawn at the latest by September 2016. Attention is drawn to the possibi

13、lity 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 24505:1993. According to the CEN-CENELEC Internal Regulations, the national standards organ

14、izations 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,

15、Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 4499-4:2016 has been approved by CEN as EN ISO 4499-4:2016 without any modification. BS EN ISO 4499-4:2016ISO 4499-4:2016(E)Forewor

16、d ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 Symbols and Units . 15 Principle 26 Apparatus . 27 Calibration of measurement apparatus . 28 Preparation of test samples 28.1 Methods of preparation . 28.2 Characterisation of porosity and carbon (graphite) defects . 3

17、8.3 Characterisation of eta-phase 39 Procedure. 39.1 General . 39.2 Determination of porosity . 39.3 Determination of carbon defects . 49.4 Determination of the -phase (eta-phase) 710 Uncertainty of measurement . 911 Test report . 9Bibliography .10 ISO 2016 All rights reserved iiiContents PageBS EN

18、ISO 4499-4:2016ISO 4499-4:2016(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 technical committees. Each member body inter

19、ested 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

20、 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 docume

21、nts 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

22、 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 th

23、e convenience of users and does not constitute an endorsement.For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the WTO principles in the Technical Barriers to Trade (TBT) see the following URL: Fo

24、reword - Supplementary information.The committee responsible for this document is ISO/TC 119, Powder metallurgy, Subcommittee SC 4, Sampling and testing methods for hardmetals.This first edition of ISO 4499-4 cancels and replaces ISO 4505:1978, which has been technically revised.ISO 4499 consists of

25、 the following parts, under the general title Hardmetals Metallographic determination of microstructure: Part 1: Photomicrographs and description Part 2: Measurement of WC grain size Part 3: Measurement of microstructural features in Ti (C,N) and WC/cubic carbide based hardmetals Part 4: Characteris

26、ation of porosity, carbon defects and eta-phase contentiv ISO 2016 All rights reservedBS EN ISO 4499-4:2016ISO 4499-4:2016(E)IntroductionIn standard WC/Co hardmetals, the chemistry, magnetic properties and density are generally controlled so that only two phases WC and Co are present.123The Co phase

27、 is an alloy and contains some W and C in solid solution. The WC phase is stoichiometric. If the composition is either high or low in total carbon content, then it is possible to see a third phase in the structure. For high C, this is graphite; for low C, it is eta phase (); typically, an M6C or M12

28、C carbide where M is (CoxWy). This part of ISO 4499 is concerned with the detection and measurement of these microstructural features together with the measurement of porosity levels. Porosity is important since these materials are manufactured by a powder metallurgical route and although the techni

29、que of liquid phase sintering is used to consolidate the multiphase structure, low levels of porosity can arise in some instances and affect properties such as density and strength. ISO 2016 All rights reserved vBS EN ISO 4499-4:2016BS EN ISO 4499-4:2016Hardmetals Metallographic determination of mic

30、rostructure Part 4: Characterisation of porosity, carbon defects and eta-phase content1 ScopeThis part of ISO 4499 specifies methods for the metallographic determination of the presence, type, and distribution of porosity, uncombined carbon and eta-phase in hardmetals.2 Normative referencesThe follo

31、wing 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 4499-2:2008,

32、Hardmetals Metallographic determination of microstructure Part 2: Measurement of WC grain size3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.3.1carbon defectsmacroscopic precipitates of carbon (graphite) which can be in the form of large angular r

33、osettes or small flakes3.2eta-phase-phasecubic carbide based on M6C or M12C structure where M is a mixture of Co and W usually in equal proportions; and which can be present as large (up to 100 m diameter) rosettes or small micrometre-sized particles4 Symbols and UnitsECD Equivalent Circle Diameter

34、of a specified phase, in micrometres (m)L total line length in a specified phase, in millimetres (mm)limeasured length of individual intercepts in a specified phase, in micrometres (m)lisum of the measured length of each individual interceptlxarithmetic mean linear intercept in phase x, in micrometr

35、es (m)INTERNATIONAL STANDARD ISO 4499-4:2016(E) ISO 2016 All rights reserved 1BS EN ISO 4499-4:2016ISO 4499-4:2016(E)N number of eta-phase particles interceptedm magnificationmmaxmaximum magnificationmminminimum magnification5 PrincipleThis part of ISO 4499 handles the following key issues: descript

36、ion of methods for sample preparation; description of how to identify and measure the relevant feature.In some cases, the approach adopted in ISO 4499-2 and ISO 4499-3 can be useful, whereby the intercept method is used on microphotographs of the structure for relevant quantification of feature size

37、, such as eta-phase or graphite rosettes.6 Apparatus6.1 Metallographic optical microscope, or other suitable equipment permitting observations and measurements on a screen up to the required magnification.6.2 Scanning electron microscope (SEM), permitting observations and measurements of features to

38、o small to be resolved with an optical microscope.6.3 Equipment for preparation of test-piece sections.7 Calibration of measurement apparatusFor reliable quantitative measurements, images shall be calibrated against a stage micrometre or scale traceable to a National Reference Standard. The most com

39、monly used stage micrometres for SEMs are the SIRA grids. These are ruled lines which form a grid and are available with 19,7 lines/mm and 2 160 lines/mm. However, these shall also be calibrated and certified as being traceable to a National Reference Standard.For images obtained from an optical mic

40、roscope, an image of the calibration graticule shall also be obtained using the same objectives (and internal magnification step changers or zoom position) and illuminating technique. The microscope shall be set up for Khler illumination to obtain the maximum resolution, see Reference 4.For images o

41、btained from a scanning electron microscope, images of the graticule should be obtained under the same conditions (accelerating kV, working distance, illumination aperture) as those used for the hardmetal.8 Preparation of test samples8.1 Methods of preparationThere are several methods for the prepar

42、ation of hardmetal surfaces for metallographic examination. For example, a detailed description is given in ISO 4499-1. Firstly, careful coarse grinding is carried out to remove sufficient material to ensure that the true structure is revealed. After grinding with fine diamond grit wheels, polishing

43、 is effected by using diamond paste or diamond powders of progressively finer grain size down to 1 m on rigidly supported laps of, for example, thin plastic, thin felt or paper.2 ISO 2016 All rights reservedBS EN ISO 4499-4:2016ISO 4499-4:2016(E)8.2 Characterisation of porosity and carbon (graphite)

44、 defectsFor porosity and carbon defects, the test-piece section shall be prepared as for metallographic examination and the surface to be examined shall be free from grinding and polishing marks. Care shall be taken to avoid tearing out of particles, which can lead to a misleading evaluation of poro

45、sity.8.3 Characterisation of eta-phaseEtching is necessary to reveal eta-phase particles (see 9.4). Eta-phase is metal carbide (usually M6C or M12C, where M is a combination of Co and W, for example, Co3W3C), that forms when the overall carbon content of the hardmetal is relatively low. Generally, i

46、t can grow in one of two morphologies, either as large rosettes or as small particles of a similar size to the other hard phases (WC or cubic carbides) present in the hardmetal (see 9.4). The presence of the eta-phase is usually determined after light etching in 10 % Murakamis reagent for a few seco

47、nds with immediate water flush following etching (see ISO 4499-1), which works well for identifying large eta-phase rosettes. When the eta-phase is present as smaller particles (see Figure 6), it is recommended to use a 5 % Murakamis solution for 20 min followed by washing the sample with water. In

48、both cases, the surface should be dried carefully with acetone or alcohol without wiping.9 Procedure9.1 GeneralIf the porosity or uncombined carbon is not uniform over the area of the test piece section being examined, the locations on the section to which the evaluation refers shall be identified,

49、for example, as top, bottom, edge, rim (case), core, etc.It should to be noted that the figures given in this Clause are only representing approximately 17of the field of view in the microscope.9.2 Determination of porosityPore size is defined as the maximum dimension of the pore in the section. Special reference shall be made to the presence of cracks or slits.9.2.1 Pores up to 10 m shall be assessed by scanning the surface of the test-piece section at a magnification of either 100 or 200. An area fully representativ