1、BRITISH STANDARDBS EN ISO 3738-2:2006Hardmetals Rockwell hardness test (scale A) Part 2: Preparation and calibration of standard test blocksThe European Standard EN ISO 3738-2:2006 has the status of a British StandardICS 77.160; 77.040.10g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g4
2、4g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58BS EN ISO 3738-2:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 28 April 2006 BSI 2006ISBN 0 580 48
3、167 0National forewordThis British Standard is the official English language version of EN ISO 3738-2:2006. It is identical with ISO 3738-2:1988.The UK participation in its preparation was entrusted to Technical Committee ISE/65, Sintered metal components, which has the responsibility to: A list of
4、organizations represented on this committee can be obtained on request to its secretary.Cross-referencesThe British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Corr
5、espondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not
6、of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep UK interests informed; monitor related international and European developments an
7、d promulgate them in the UK.Summary of pagesThis document comprises a front cover, an inside front cover, the EN ISO title page, the EN ISO foreword page, the ISO title page, the ISO foreword page, pages 1 to 4, an inside back cover and a back cover.The BSI copyright notice displayed in this documen
8、t indicates when the document was last issued.Amendments issued since publicationAmd. No. Date CommentsEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 3738-2April 2006ICS 77.160; 77.040.10English VersionHardmetals - Rockwell hardness test (scale A) - Part 2:Preparation and calibration of stand
9、ard test blocks (ISO 3738-2:1988)Mtaux durs - Essai de duret Rockwell (chelle A) - Partie2: Prparation et talonnage des blocs de rfrence (ISO3738-2:1988)Hartmetalle - Rockwell-Hrteprfung (Skala A) - Teil 2:Vorbereitung und Kalibrierung von Standard-Prfblcken(ISO 3738-2:1988)This European Standard wa
10、s approved by CEN on 9 March 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such nation
11、alstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a CEN member into its own language and notifie
12、d to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands,
13、Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of exploitation in any form
14、 and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 3738-2:2006: EForeword The text of ISO 3738-2:1988 has been prepared by Technical Committee ISO/TC 119 “Powder metallurgy” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 3738-2
15、:2006 by Technical Committee CEN/SS M11 “Powder metallurgy“, the secretariat of which is held by CMC. 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 2006, and conflicting national standar
16、ds shall be withdrawn at the latest by October 2006. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany,
17、 Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 3738-2:1988 has been approved by CEN as EN ISO 3738-2:2006 without an
18、y modifications. EN ISO 3738-2:2006INTERNATIONAL STANDARD 3738-2 INTERNATIONAL ORGANIZATDON FOR STANDARDIZATION ORGANISATION INTERNATIONALE DE NORMALISATION MEXAYHAPO,QHAR OPTAHM3AMR l-l0 CTAHflAPTM3AMM Hardmetals - Rockwell hardness test (scale A) - Part 2 : Preparation and calibration of Standard
19、test blocks Mtaux durs - Essai de duretk Rockwell fechelle Al - Partie 2: Prbpara tion et 6 talonnage des blocs de rhference ISO First edition 1988-12-15 Reference number ISO 3738-2: 1988 (E) EN ISO 3738-2:2006Foreword ISO (the International Organization for Standardization) is a worldwide federatio
20、n of national Standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Esch member body interested in a subject for which a technical committee has been established has the right to be represented on that committee.
21、 International organizations, govern- mental 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. Draft International Standards adopted by the techn
22、ical committees are circulated to the member bodies for approval before their acceptance as International Standards by the ISO Council. They are approved in accordance with ISO procedures requiring at least 75 % approval by the member bodies voting. International Standard ISO 3738-2 was prepared by
23、Technical Committee ISO/TC 119, Powder me tallurg y. Users should note that all International Standards undergo revision from time to time and that any reference made herein to any other International Standard implies its latest edition, unless otherwise stated. EN ISO 3738-2:2006Hardmetals - Rockwe
24、ll hardness test (scale A) - Part 2 : Preparation and calibration of Standard test blocks 1 Scope and field of application This part of ISO 3738 specifies the preparation and calibration of hardmetal primary Standard test blocks, secondary Standard test blocks and working Standard test blocks from m
25、aster stan- dard test blocks to be used for the verification of Rockwell hardness testing machines (scale A) and indenters for testing hardmetals. This document should be read in conjunction with ISO 3738-1. 2 Reference ISO 3738-1, liardmetals - Rockwell hardness test fscale Al - Part 7 : Pest metho
26、d. 3 Symbols and designations Table 1 Designation Standard deviation of hardness determinations on the first sur-face of a primary Standard test block Standard deviation of hardness determinations on the test surface of a primary Standard test block Mean Standard deviation of hardness determi- natio
27、ns on a primary Standard test block. Standard deviations shall be calculated using the equation than a total of 1 % (mlm) of other carbides 1e.g. of titanium, tantalum, niobium). The composition and structure shall be Chosen to give the desired hardness. Free carbon and eta- Phase shall be absent. 4
28、.2 Standard test blocks shall have a nominal diameter of 45 mm and a nominal thickness of 8 mm. The bottom face shall be chamfered 0,8 mm by 45O. 4.3 Every Standard test block shall be ground on both flat faces. The face on which indentations are to be made shall have a surface finish of R, 0,2 Pm,
29、and may be polished. The maximum deviation in flatness of the surfaces shall not exceed 0,010 mm. The bottom of the blocks shall not be convex. The maximum deviation in parallellism shall not exceed 0,020 mm per 50 mm. 5 Master standard test blocks 5.1 Two sets of five master Standard test blocks ea
30、ch shall be retained by the Cemented Carbide Producers Association ICCPA), USA, and one set shall be retained by the Secretariat of ISO/TC 119. One of the sets retained in the USA shall be used for calibrating primary Standard test blocks. 5.2 The markings and internationally agreed hardnesses and S
31、tandard deviations of three sets sf the five master test blocks are given in tables 2a), 2b) and 2). Table 2a) - Set one retained by CXPA 4 Preparation of Standard test blocks 4.1 All Standard test blocks referred to in this part of ISO 3738 shall comprise hardmetals composed substantially of tungst
32、en carbide and Cobalt without other carbides or with less Marking Hardness Standard deviation 2 series I 85,70 0,07 6 series El =,m 0,07 8 series Ill 91,08 0,06 2 series IV 91,59 0,04 8 series V 92,80 0,05 EN ISO 3738-2:2006Table 2b) - Set two retained by CCPA indentations shall then be made in such
33、 a way as to cover the whole test surface of the primary Standard test block and the Standard deviation (SJ of the results shall be calculated. Marking Standard deviation Hardness 4 series I 0,08 10 series II 0,08 6 series Ill 0,06 12 series IV 0,04 5 series V 0,08 6.6 After establishing uniformity,
34、 a further 0,35 mm shall be removed from the tested surface of the primary Standard test block (sec 4.3). The block is then ready to be calibrated. 6.7 Ten indentations shall be made on the test surface of the master Standard test block whose hardness is nearest to that of the primary Standard. The
35、arithmetic mean of the results shall be calculated to the nearest 0,Ol HRA and subtracted from the agreed hardness sf the block (see 5.2). The result is the correc- tion for the given combination of testing machine and indenter. Table 24 - Set retained by the secretariat of ISO/TC 119 Marking Standa
36、rd deviation Hardness 6 series I 85,69 0,07 5 series II 88,56 0,07 1 series Ill 91,06 0,06 14 series IV 91,60 0,06 6 series V 92,79 0,08 6.8 If the correction is greater than 020 HRA absolute, the machine and indenter shall be examined to ascertain the Cause. The test in 6.7 shall then be repeated.
37、NOTE - in such a The Standard deviation is calcula way as to cover the whole test ted on 40 surface. indentations made 6.9 Twenty indentations shall be made on the new test sur- face of the primary Standard test block and the Standard devi- ation (2) of the result shall be calcuiated. 5.3 The blocks
38、 shall not be reground and, to ensure that this has not been done, their thickness at the time of the calibration shall be measured and recorded. 6.10 The mean Standard deviation (SJ shall be calculated using the equation 5.4 Of the three sets in tables Za), 2b) and 2c), one of the sets retained by
39、CCPA shall be used for calibrating primary Standard test blocks. The other two sets shall be retained as permanent Standards, to be used only when a new master stan- dard is required. Blocks retained by ISO/TC 119 shall only be released by Permission of ISO/TC 119/SC 4. If sr, is greater than 0,07 H
40、RA, the block is too variable and shall be discarded. 6.11 ff the Standard deviation is acceptable, the arithmetic mean of the 20 results obtained according to 6.9 shall be calculated to the nearest 0,Ol HRA and corrected for the error of machine and indenter obtained according to 6.7. 6 Primary Sta
41、ndard test blocks 6.1 Primary Standard test blocks shall be prepared in sets of nominal hardnesses of 93,92, 91,88,5 and 85,5 HRA. Esch set shall comprise five blocks, one block of each nominal hardness. The result shall be rounded off to the nearest 0,02 HRA and shall be recorded together with the
42、date as the hardness of the primary Standard test block. To avoid excessive use of the test surface of the master stan- dard test blocks, the primary Standard test blocks shall be prepared and calibrated in groups of not less than 10 blocks of the same nominal hardness. 6.12 When calibrating a numbe
43、r of primary Standard test blocks of the same nominal hardness in an uninterrupted series, the correction may be determined only at the commencement of the series, unless there is reason to believe that the correc- tion may have altered. 6.2 Esch block shall be marked on the peripher-y with the lett
44、ers CCPA, with a number 1, II, Ill, IV or V, corresponding to the nominal hardness, and with one, two or three digits denoting the serial number. 6.13 The thickness of the primary Standard test block shall be measured and recorded together with the date on which it was calibrated. 6.3 Hardness measu
45、rements shall be made in accordance with the relevant clauses of ISO 3738-1, except that in 5.1 the testing equipment shall be such that the measurement tan be made to the nearest 0,l HRA and the form of the indenter shall be verified in accordance with sub-clause 5.2.2 of ISO 3738-1. 6.14 The test
46、sur-face sf primary Standard test blocks shall not be reground unless they are then recalibrated against the master Standard test blocks. NOTE - Primary Standard test blocks tan be obtained from the CAPA. 6.4 At least 0,35 mm shall be removed from the test surface (sec 4.3). 7 Secondary Standard tes
47、t blocks 7.1 Secondary Standard test blocks shall be prepared and calibrated against primary Standard test blocks, to avoid using the test sur-face of primary Standard test blocks excessively. 65 metal Three indentations shall be made on any piece of hard- to ensure that the indenter is firm in the
48、machine. Twenty 2 EN ISO 3738-2:20067.2 Secondary Standard test blocks shall be prepared in sets of five of nominal hardnesses of 93,92, 91,88,5 and 85,5 HRA. 8 Working Standard test blocks 73 letter Esch block shall be mar S and a serial number. ,ked on the periphery with the 7.4 Hardness measureme
49、nts shall be made in accordance with 6.3 except that the indenter shall be checked in accord- ante with 7.6 and 7.7. 7.5 Secondary Standard test blocks shall conform to the re- quirements of clause 4, and at least 0,35 mm shall be ground off the test surface. 7.6 A primary Standard test block shall be Chosen having a hardness nearest to that of the secondary Standard test block, and 20 indentations shall be made on its test surface. The arithmetic mean of the 20 results shall be calculated to the nearest 0,Ol HRA and subtracted from the calibrated hardness o
