1、BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06Metallic powders, excluding powders for hardmetals Determination of dimensional changes associated with compacting and sinteringBS EN ISO 4492:2017National forewordThis British Standard is the UK implementation of EN IS
2、O 4492:2017. It is identical to ISO 4492:2017. It supersedes BS EN ISO 4492:2013, which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee ISE/65, Sintered metal components.A list of organizations represented on this committee can be obtained on request to its
3、secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2017 Published by BSI Standards Limited 2017ISBN 978 0 580 97217 1ICS 77.160Compliance with a British Standard canno
4、t confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 December 2017.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS EN ISO 4492:2017EUROPEAN STANDARDNORME EUROPENNEEUROP
5、ISCHE NORMEN ISO 4492November 2017ICS 77.160 Supersedes EN ISO 4492:2013EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGCEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2017 CEN Ref. No. EN ISO 4492:2017: EAll rights of exploitation i
6、n any form and by any means reserved worldwide for CEN national MembersMetallic powders, excluding powders for hardmetals - Determination of dimensional changes associated with compacting and sintering (ISO 4492:2017)Poudres mtalliques lexclusion des poudres pour mtaux-durs - Dtermination de changem
7、ents dimensionnels lis la compression et au frittage (ISO 4492:2017)Metallpulver, mit Ausnahme von Hartmetallpulvern - Ermittlung der Manderungen beim Pressen und Sintern (ISO 4492:2017)This European Standard was approved by CEN on 2 November 2017.CEN members are bound to comply with the CEN/CENELEC
8、 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 t
9、o 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 officia
10、l 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, Nor
11、way, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.English VersionEN ISO 4492:2017 (E)European forewordThis document (EN ISO 4492:2017) has been prepared by Technical Committee ISO/TC 119 “Powder metallurgy”.This European Standard shall
12、be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2018, and conflicting national standards shall be withdrawn at the latest by May 2018.Attention is drawn to the possibility that some of the elements of this document may be
13、 the subject of patent rights. CEN shall not be held responsible for identifying any or all such patent rights.This document supersedes EN ISO 4492:2013.According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this Euro
14、pean 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, Slova
15、kia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom.Endorsement noticeThe text of ISO 4492:2017 has been approved by CEN as EN ISO 4492:2017 without any modification.2BS EN ISO 4492:2017ISO 4492:2017(E)Foreword iv1 Scope . 12 Normative references 13 Terms and definitions . 14 Pr
16、inciple 15 Test parameters . 15.3 From die size to sintered size (total dimensional change). 26 Symbols and designations 27 Apparatus . 28 Sampling 29 Procedure. 210 Expression of results 310.1.1 Green dimensional change (spring back) . 310.1.2 Sintered dimensional change (positive or negative) 310.
17、1.3 Total dimensional change (positive or negative) . 311 Test report . 4Annex A (informative) Information on dimensional change behaviour . 9 ISO 2017 All rights reserved iiiContents PageBS EN ISO 4492:2017ISO 4492:2017(E)ForewordISO (the International Organization for Standardization) is a worldwi
18、de 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 tha
19、t 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 docum
20、ent 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 Directive
21、s, 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
22、 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 st
23、andards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs 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 pr
24、epared by Technical Committee ISO/TC 119, Powder metallurgy, Subcommittee SC 2, Sampling and testing methods for powders (including powders for hardmetals).This fourth edition cancels and replaces the third edition (ISO 4492:2013), of which it constitutes a minor revision to adjust tolerances and ge
25、ometry in Figures 1 and 2 and clarify the use of scale and micrometer.iv ISO 2017 All rights reservedBS EN ISO 4492:2017Metallic powders, excluding powders for hardmetals Determination of dimensional changes associated with compacting and sintering1 ScopeThis document specifies a method by which the
26、 dimensional changes associated with compacting and sintering of metallic powders are compared with those of a reference powder when processed under similar conditions (see Clause 4).The method applies to the determination of three types of dimensional changes involved with the processing of metalli
27、c powders, excluding powders for hardmetals.2 Normative referencesThe 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 ed
28、ition of the referenced document (including any amendments) applies.ISO 2740, Sintered metal materials, excluding hardmetals Tensile test pieces3 Terms and definitionsNo terms and definitions are listed in this document. ISO and IEC maintain terminological databases for use in standardization at the
29、 following addresses: ISO Online browsing platform: available at http:/www.iso.org/obp IEC Electropedia: available at http:/www.electropedia.org/ 4 PrincipleCompaction of a metallic powder or powder mix with admixed lubricant was used to produce a test piece that was sintered under controlled condit
30、ions. Depending upon the particular dimensional change required, measurement of the dimension of the uploaded die cavity, the green compact, and/or the sintered test piece is calculated. The algebraic difference between these various measurements is calculated as a percentage of the dimension of the
31、 die cavity or the green compact. (See Clause 9.)Standard test pieces made from a reference lot of powder are processed together with the sample under test and the dimensional changes of the two powders are reported (see Annex A for additional information).5 Test parametersThe reference powder shall
32、 be chosen by agreement between the supplier and user and shall have a composition and properties as close as possible to those of the powder to be tested.The following three types of dimensional changes are dealt with in this document:5.1 From die size to green size (spring back): The increase in d
33、imensions of a compact, measured at right angles to the direction of pressing, after being ejected from the die.INTERNATIONAL STANDARD ISO 4492:2017(E) ISO 2017 All rights reserved 1BS EN ISO 4492:2017ISO 4492:2017(E)5.2 From green size to sintered size (sintered dimensional change): The change in d
34、imensions of an object that occurs as a result of sintering.5.3 From die size to sintered size (total dimensional change).6 Symbols and designationsSymbol Designation UnitdDTest dimension of unloaded die mmdGTest dimension of green compact mmdSTest dimension of sintered compact mm dDGSpring back % (
35、+) dGSSintered dimensional change % (+ or ) dDSTotal dimensional change % (+ or )7 Apparatus7.1 Tools set, that will produce cylindrical (see Figure 1), rectangular (see Figure 2) or tensile test pieces (in accordance with ISO 2740), or test pieces similar to the actual components for which the powd
36、er is required.7.2 Press, capable of applying the pressures necessary to achieve the required density or required compacting pressure. See Figure 3.7.3 Scale, capable of weighing at least 100 g and readable to 0,001 g.7.4 Micrometer, or other suitable measuring device readable to 0,005 mm for measur
37、ing the dimensions of the compacts and the die.7.5 Sintering furnace, capable of producing sintering conditions (time-temperature curve and atmosphere) as close as possible to those used in industry for the type of material to be tested.8 SamplingRepresentative quantities of both the test and the re
38、ference powders sufficient to give at least three compacts shall be taken.9 Procedure9.1 The test powder and the reference powder shall be mixed under the same conditions with the same mass of additives, including lubricant, each taken from the same batch, to produce the composition of the sintered
39、components for which the powder is required.A test powder supplied ready for pressing shall be tested in the as-received condition.To avoid the possibility of distortion during sintering, it is recommended that the test pieces should not be less than 5 mm thick.9.2 Measure, to the nearest 0,005 mm,
40、the test dimension (diameter or length) of the die in the unloaded condition and record the value d Dobtained.2 ISO 2017 All rights reservedBS EN ISO 4492:2017ISO 4492:2017(E)9.3 Press, at the agreed density or agreed compacting pressure, at least three compacts from the test and reference powders p
41、repared as in 8.1.9.4 Measure, to the nearest 0,005 mm, the test dimension of the green compact and record the value d Gobtained.9.5 Sinter the test and reference compacts adjacent to each other under the conditions of time, temperature and atmosphere, which simulate production conditions to be used
42、 for the sintered components for which the test powder is required. The support used for the test pieces to prevent distortion (i.e. ceramic plate or furnace belt), the rate of heat-up, the atmosphere, and the cooling rate may affect the dimensional change being measured and should be consistent.9.6
43、 After cooling to room temperature, measure, to the nearest 0,005 mm, the test dimension of the sintered test and reference compacts and record the value d Sobtained, ensuring that the dimensions before and after sintering are taken from the same position on the compacts.10 Expression of results10.1
44、 The dimensional changes, expressed as percentages, are given in Formulae (1) to (3).10.1.1 Green dimensional change (spring back)=ddddDGGDD100 (1)10.1.2 Sintered dimensional change (positive or negative)ddddGSSGG=100 (2)10.1.3 Total dimensional change (positive or negative)ddddDSSDD=100 (3)10.2 Rep
45、ort the dimensional changes for both the test and reference powders as the average of at least three determinations, rounded to the nearest 0,01 %. ISO 2017 All rights reserved 3BS EN ISO 4492:2017ISO 4492:2017(E)11 Test reportThe test report shall include the following information:a) a reference to
46、 this document, i.e. ISO 4492;b) all details necessary for identification of the test sample;c) all details necessary for identification of the reference powder;d) the type of test piece, and its dimensions before sintering;e) the density of the green compact or if the compacts were pressed to a req
47、uired compacting pressure;f) sintering details;g) the result obtained;h) all operations not specified by this document, or regarded as optional;i) details of any occurrence which may have affected the result.4 ISO 2017 All rights reservedBS EN ISO 4492:2017ISO 4492:2017(E)Dimensions in millimetresa)
48、 Upper punch, L = H 10 b) Die, H = 60 mm to 80 mm c) Lower punch, L = H + 35Key1 cemented carbide2 shrink ringH height of tool dieFigure 1 Example of tooling to produce a cylindrical test piece ISO 2017 All rights reserved 5BS EN ISO 4492:2017ISO 4492:2017(E)Dimensions in millimetresa) Upper punch,
49、L = 25 b) Die 6 ISO 2017 All rights reservedBS EN ISO 4492:2017ISO 4492:2017(E)c) Lower punch, L = 70Key1 cemented carbide2 shrink ringaSteel, HRC 60 to 62.Figure 2 Example of tooling to produce a rectangular test piecea) Filling b) Pre-compacting ISO 2017 All rights reserved 7BS EN ISO 4492:2017ISO 4492:2017(E)c) Compacting d) EjectionKey1 tool die2 sample powder3 spacer4 lower punch5 upper punchFigure 3 Procedure of compacting and ejection8 ISO 2017 All rights reservedBS EN ISO 4492:2017ISO 4492:2017
