1、 DEUTSCHE NORMJune 2006DIN EN ISO 3738-2 ICS 77.040.10; 77.160 Hardmetals Rockwell hardness test (scale A) Part 2: Preparation and calibration of standard test blocks (ISO 3738-2:1988) English version of DIN EN ISO 3738-2:2006-06 Hartmetalle Rockwell-Hrteprfung (Skala A) Teil 2: Vorbereitung und Kal
2、ibrierung von Standard-Prfblcken (ISO 3738-2:1988) Englische Fassung DIN EN ISO 3738-2:2006-06 Document comprises 8 pages No part of this standard may be reproduced without prior permission of DIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany, has the exclusiv
3、e right of sale for German Standards (DIN-Normen). English price group 8 www.din.de www.beuth.de !,o4C“11.06 9761732DIN EN ISO 3738-2:2006-06 2 National foreword This standard has been published in accordance with a decision taken by CEN/SS M11 to adopt, without alteration, International Standard IS
4、O 3738-2 as a European Standard. The responsible German body involved in its preparation was the Normenausschuss Werkstofftechnologie (Materials Technology Standards Committee), Technical Committee NA 145-01-04 AA Probenahme und Prf-verfahren fr Hartmetalle. The DIN Standard corresponding to the Int
5、ernational Standard referred to in clause 2 of the EN is as follows: ISO 3738-1 DIN ISO 3738-1 National Annex NA (informative) Bibliography DIN ISO 3738-1, Hardmetals Rockwell hardness test (scale A) Part 1: Test method EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 3738-2 April 2006 ICS 7
6、7.160; 77.040.10 English Version Hardmetals - Rockwell hardness test (scale A) - Part 2: Preparation and calibration of standard test blocks (ISO 3738-2:1988) Mtaux durs - Essai de duret Rockwell (chelle A) - Partie 2: Prparation et talonnage des blocs de rfrence (ISO 3738-2:1988) Hartmetalle - Rock
7、well-Hrteprfung (Skala A) - Teil 2: Vorbereitung und Kalibrierung von Standard-Prfblcken (ISO 3738-2:1988) This European Standard was 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 European Sta
8、ndard 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 Central Secretariat or to any CEN member. This European Standard exists in three official versions (English, French
9、, 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 Central Secretariat has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republi
10、c, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NO
11、RMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2006 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 3738-2:2006: EForeword The text of ISO 3738-2:1988 has been prepared by Tech
12、nical Committee ISO/TC 119 “Powder metallurgy” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 3738-2:2006 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
13、 a national standard, either by publication of an identical text or by endorsement, at the latest by October 2006, and conflicting national standards shall be withdrawn at the latest by October 2006. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the follo
14、wing countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spai
15、n, 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 any modifications. EN ISO 3278-2:2006 (E)21 Scope and field of application This part of ISO 3738 specifies the preparation and calibration of hardmetal pri
16、mary Standard test blocks, secondary Standard test blocks and working Standard test blocks from master 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 373
17、8-1. 2 Reference ISO 3738-1, liardmetals - Rockwell hardness test fscale Al - Part 7 : Pest method. 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
18、 test surface of a primary Standard test block Mean Standard deviation of hardness determi- nations 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 stru
19、cture shall be Chosen to give the desired hardness. Free carbon and eta- Phase shall be absent. 4.2 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 fla
20、t faces. The face on which indentations are to be made shall have a surface finish of R, 0,2 Pm, 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 0,02
21、0 mm per 50 mm. 5 Master standard test blocks 5.1 Two sets of five master Standard test blocks each 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 calib
22、rating primary Standard test blocks. 5.2 The markings and internationally agreed hardnesses and Standard 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 block
23、s referred to in this part of ISO 3738 shall comprise hardmetals composed substantially of tungsten 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,
24、05 EN ISO 3738-2:2006 (E)3Table 2b) - Set two retained by CCPA indentations shall then be made in such 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
25、 series II 0,08 6 series Ill 0,06 12 series IV 0,04 5 series V 0,08 6.6 After establishing uniformity, 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 sur
26、face of the master Standard test block whose hardness is nearest to that of the primary Standard. The 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
27、 testing machine and indenter. Table 24 - Set retained by the secretariat of ISO/TC 119 Marking Standard 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 m
28、achine and indenter shall be examined to ascertain the Cause. The test in 6.7 shall then be repeated. 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
29、Standard test block and the Standard devi- ation (2) of the result shall be calcuiated. 5.3 The blocks 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 calcul
30、ated using the equation 5.4 Of the three sets in tables Za), 2b) and 2c), one of the sets retained by 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 retaine
31、d by ISO/TC 119 shall only be released by Permission of ISO/TC 119/SC 4. If sr, is greater than 0,07 HRA, 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
32、 0,Ol HRA and corrected for the error of machine and indenter obtained according to 6.7. 6 Primary Standard 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 hard
33、ness. The result shall be rounded off to the nearest 0,02 HRA and shall be recorded together with the 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 calib
34、rated in groups of not less than 10 blocks of the same nominal hardness. 6.12 When calibrating a number 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
35、that the correc- tion may have altered. 6.2 Esch block shall be marked on the peripher-y with the letters 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 bloc
36、k shall be measured and recorded together with the date on which it was calibrated. 6.3 Hardness measurements 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 fo
37、rm of the indenter shall be verified in accordance with sub-clause 5.2.2 of ISO 3738-1. 6.14 The test 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
38、 CAPA. 6.4 At least 0,35 mm shall be removed from the test surface (sec 4.3). 7 Secondary Standard test 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 me
39、tal Three indentations shall be made on any piece of hard- to ensure that the indenter is firm in the machine. Twenty EN ISO 3278-2:2006 (E)47.2 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 le
40、tter Esch block shall be mar S and a serial number. ,ked on the periphery with the 7.4 Hardness measurements 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 clau
41、se 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
42、to the nearest 0,Ol HRA and subtracted from the calibrated hardness of the primary Standard test block. The result is the correction for the given combination of testing machine and indenter. 7.7 If the correction is greater than 0,3 HRA absolute, the machine and indenter shall be examined to ascert
43、ain the Cause. The test in 7.6 shall then be repeated. 7.8 Twenty indentations shall be made on the test surface of the secondary Standard test block and the Standard deviation (SJ of the results shall be calculated. 7.9 If the Standard deviation is greater than 0,lO HRA, the block shall be discarde
44、d, but if it is not greater than 0,lO HRA, the arithmetic mean of the 20 results shall be calculated to the nearest 0,Ol HRA and corrected for the error of machine and indenter obtained according to 7.6. The result shall be rounded off to the nearest 0,02 HRA and shall be recorded together with the
45、date as the hardness of the secondary Standard test block. The actua desired. I ha rdness values may be on the periphery if 7.10 When calibrating a number of secondary Standard test blocks of the same nominal hardness in an uninterrupted series, the correction may be determined only at the commencem
46、ent of the series, unless there is reason to believe that the correc- tion may have altered. 7.11 The thickness of the secondary Standard test block shall be measured and recorded together with the actual hardness value and the date on which it was calibrated. 7.12 The test surface of secondary Stan
47、dard test blocks shall not be reground unless they are then recalibrated against the primary Standard test blocks. NOTE - Secondary Standard test blocks may be manufactured by any organization possessing the equipment which meets the requirements of this part of ISO 3738. 8.1 Working Standard test b
48、locks shall be prepared and calibrated against secondary Standard test blocks to avoid excessive use of the test surface of secondary Standard test blocks. 8.2 Working Standard test blocks may be prepared in sets of from one to five (depending on the range of hardnesses of test pieces to be measured
49、), so as to have some or all of the follow- ing nominal hardnesses: 93, 92, 91, 88,5 and 85,5 HRA. 8.3 Esch block shall be marked letter W and a serial number. on the periphery with the 8.4 Working Standard test blocks shall conform to the re- quirements of 7.5. 8.5 The blocks shall be calibrated in accordance with 7.6 to 7.12, with the following alterations. 8.5.1 The words “primary Standard test blocks” shall be replaced by “secondary Standard test blocks”, and the words “secondary Standard test blocks” shall be replaced by “work- ing Standard test
