1、BRITISH STANDARD BS EN ISO 4545-2:2005 Metallic materials Knoop hardness test Part 2: Verification and calibration of testing machines The European Standard EN ISO 4545-2:2005 has the status of a British Standard ICS 77.040.10 BS EN ISO 4545-2:2005 This British Standard was published under the autho
2、rity of the Standards Policy and Strategy Committee on 30 January 2006 BSI 30 January 2006 ISBN 0 580 47639 1 National foreword This British Standard is the official English language version of EN ISO 4545-2:2005. It is identical with ISO 4545-2:2005. The UK participation in its preparation was entr
3、usted by Technical Committee ISE/NFE/4, Mechanical testing of metals, to Subcommittee ISE/NFE/4/5, Indentation/hardness testing, which has the responsibility to: aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or
4、proposals for change, and keep UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement in
5、ternational or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not p
6、urport to include all the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the EN ISO tit
7、le page, the EN ISO foreword page, the ISO title page, pages ii to iv, pages 1 to 14, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. Date CommentsEUROPEANSTANDARD NOR
8、MEEUROPENNE EUROPISCHENORM ENISO45452 November2005 ICS77.040.10 EnglishVersion MetallicmaterialsKnoophardnesstestPart2:Verification andcalibrationoftestingmachines(ISO45452:2005) MatriauxmtalliquesEssaideduretKnoopPartie2: Vrificationettalonnagedesmachinesdessai(ISO4545 2:2005) MetallischeWerkstoffe
9、HrteprfungnachKnoopTeil2: PrfungundKalibrierungderPrfmaschinen(ISO4545 2:2005) ThisEuropeanStandardwasapprovedbyCENon28October2005. CENmembersareboundtocomplywiththeCEN/CENELECInternalRegulationswhichstipulatetheconditionsforgivingthisEurope an Standardthestatusofanationalstandardwithoutanyalteratio
10、n.Uptodatelistsandbibliographicalreferencesconcernings uchnational standardsmaybeobtainedonapplicationtotheCentralSecretariatortoanyCENmember. ThisEuropeanStandardexistsinthreeofficialversions(English,French,German).Aversioninanyotherlanguagemadebytra nslation undertheresponsibilityofaCENmemberintoi
11、tsownlanguageandnotifiedtotheCentralSecretariathasthesamestatusast heofficial versions. CENmembersarethenationalstandardsbodiesofAustria,Belgium,Cyprus,CzechRepublic,Denmark,Estonia,Finland,France, Germany,Greece,Hungary,Iceland,Ireland,Italy,Latvia,Lithuania,Luxembourg,Malta,Netherlands,Norway,Pola
12、nd,Portugal, Slovakia, Slovenia,Spain,Sweden,SwitzerlandandUnitedKingdom. EUROPEANCOMMITTEEFORSTANDARDIZATION COMITEUROPENDENORMALISATION EUROPISCHESKOMITEEFRNORMUNG ManagementCentre:ruedeStassart,36B1050Brussels 2005CEN Allrightsofexploitationinanyformandbyanymeansreserved worldwideforCENnationalMe
13、mbers. Ref.No.ENISO45452:2005:E Foreword This document (EN ISO 4545-2:2005) has been prepared by Technical Committee ISO/TC 164 “Mechanical testing of metals“ in collaboration with Technical Committee ECISS/TC 1 “Steel - Mechanical testing“, the secretariat of which is held by AFNOR. This European S
14、tandard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by May 2006, and conflicting national standards shall be withdrawn at the latest by May 2006. According to the CEN/CENELEC Internal Regulations, the national standard
15、s organizations of the following 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, Slova
16、kia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 4545-2:2005 has been approved by CEN as EN ISO 4545-2:2005 without any modifications. EN ISO 4545-2:2005 Reference number ISO 4545-2:2005(E)INTERNATIONAL STANDARD ISO 4545-2 First edition 2005-11-15 Meta
17、llic materials Knoop hardness test Part 2: Verification and calibration of testing machines Matriaux mtalliques Essai de duret Knoop Partie 2: Vrification et talonnage des machines dessai EN ISO 4545-2:2005ii EN ISO 4545-2:2005 iii Contents Page Foreword iv 1 Scope . 1 2 Normative references . 1 3 G
18、eneral conditions . 1 4 Direct verification 2 5 Indirect verification. 4 6 Intervals between verifications . 6 7 Verification report/calibration certificate . 6 Annex A (informative) Notes on diamond indenters 7 Annex B (informative) Uncertainty of measurement of the calibration results of the hardn
19、ess testing machine. 8 Bibliography . 14 EN ISO 4545-2:2005 iv Foreword ISO (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 com
20、mittees. 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 closely with the
21、 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 Internatio
22、nal 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 may be t
23、he subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 4545-2 was prepared by Technical Committee ISO/TC 164, Mechanical testing of metals, Subcommittee SC 3, Hardness testing. ISO 4545-2 cancels and replaces ISO 4546:1993, which has been te
24、chnically revised. ISO 4545 consists of the following parts, under the general title Metallic materials Knoop hardness test: Part 1: Test method Part 2: Verification and calibration of testing machines Part 3: Calibration of reference blocks Part 4: Table of hardness values 1 Metallic materials Knoo
25、p hardness test Part 2: Verification and calibration of testing machines 1 Scope This part of ISO 4545 specifies the method of verification of testing machines for determining Knoop hardness for metallic materials in accordance with ISO 4545-1-1. It covers test forces from 0,098 07 N to 19,614 N. Th
26、e method is recommended only for indentations with diagonals W 0,020 mm. It specifies a direct verification method for checking the main functions of the machine, and an indirect verification method suitable for the overall checking of the machine. The indirect verification method may be used on its
27、 own for periodic routine checking of the machine in service. If a testing machine is also to be used for other methods of hardness testing, it should be verified independently for each method. 2 Normative references The following referenced documents are indispensable for the application of this do
28、cument. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 376:2004, Metallic materials Calibration of force-proving instuments used for the verification of uniaxial testing machines ISO
29、4545-1:2005, Metallic materials Knoop hardness test Part 1: Test method ISO 4545-3, Metallic materials Knoop hardness test Part 3: Calibration of reference blocks 3 General conditions Before a Knoop hardness testing machine is verified, it shall be checked to ensure that it is properly set up in acc
30、ordance with the manufacturers instructions. Especially, it should be checked that: a) the mount holding the indenter is capable of moving freely without any friction or excess side play; b) the indenter is firmly mounted in the mount; c) the test force can be applied and removed without shock or vi
31、bration and in such a manner that the readings are not influenced; EN ISO 4545-2:20052 d) the measuring system is integral with the machine: the change in mode from the application and removal of the test force to the measuring mode does not influence the readings, illumination does not affect the r
32、eadings, the centre of the indentation is near the centre of the field of view. 4 Direct verification 4.1 General 4.1.1 Direct verification should be carried out at a temperature of (23 5) C. If the verification is carried out at a temperature outside this range, it shall be noted in the verificatio
33、n report. 4.1.2 The instruments used for verification and calibration shall be traceable to national standards. 4.1.3 Direct verification involves: a) calibration of the test force; b) verification of the indenter; c) calibration of the measuring system; d) verification of the testing cycle. 4.2 Cal
34、ibration of the test force 4.2.1 Each test force used (see Table 2 in ISO 4545-1:2005), within the working range of the testing machine, shall be measured. 4.2.2 The test force shall be measured by one of the following two methods: by means of an elastic proving device in accordance with ISO 376:200
35、4, class 1, or by balancing against a force, accurate to 0,2 %, applied by means of calibrated masses or another method with the same accuracy. 4.2.3 Three readings shall be taken for each test force. Immediately before each reading is taken, the indenter shall be moved in the same direction as duri
36、ng the test. All readings shall be within the tolerances defined in Table 1. Table 1 Test-force tolerances Test force, F N Tolerance % 0,098 07 u F 1,961 1,5 1,961 u F u 19,614 1,0 4.3 Verification of the indenter 4.3.1 The four faces of the diamond pyramid shall be polished and free from surface de
37、fects. EN ISO 4545-2:20053 4.3.2 Verification of the shape of the indenter can be made by direct measurement or optical measurement. The device used for the verification shall be accurate to within 0,07. 4.3.3 The angle between the opposite edges at the vertex of the diamond pyramid shall be (172,5
38、0,1) (see Figure 1). 4.3.4 The angle between the opposite edges at the vertex of the diamond pyramid shall be (130 1,0) (see Figure 1). 4.3.5 The indenter constant c (see ISO 4545-1:2005, Table 1) shall be within 1,0 % of the ideal value 0,070 28, (0,069 58 u c u 0,070 98). NOTE To achieve the toler
39、ances for the indenter constant c, the values of angle and/or angle may be kept to closer tolerances than given above. 4.3.6 The angle between the axis of the diamond pyramid and the axis of the indenter holder (normal to the seating surface) shall be within 0,5. 4.3.7 The four faces shall meet at a
40、 common point. The maximum permissible length of the line of conjunction between opposite faces shall be less than 1,0 m (see Figure 2). NOTE For indents less than 0,020 mm, the maximum permissible length of the line of conjunction should be proportionally less. The line of conjunction may be determ
41、ined by measuring an indentation. 4.4 Calibration of the measuring system 4.4.1 The system for measuring the long diagonal of the indentation shall be calibrated at each magnification to be used against an accurately ruled line scale (object micrometer) or system of equivalent accuracy. The errors o
42、f the line scale shall be known within an uncertainty of 0,1 m or 0,05 %, whichever is greater. 4.4.2 The measuring system shall be verified by measurements made on a stage micrometer at a minimum of five intervals over each working range. Figure 1 Principle of the test and indenter geometry EN ISO
43、4545-2:20054 Dimensions in m Figure 2 Line of conjunction on the top of the indenter (schematic) 4.4.3 The maximum permissible error of the measuring system shall be 0,5 % or 0,4 m, whichever is greater. If necessary, a calibration factor can be applied to comply with this tolerance. 4.5 Verificatio
44、n of the testing cycle The testing cycle shall be timed with an uncertainty of 1 s and shall conform to the testing cycle of ISO 4545-1. 5 Indirect verification 5.1 Indirect verification should be carried out at a temperature of (23 5) C by means of reference blocks calibrated in accordance with ISO
45、 4545-3. If the verification is carried out at a temperature outside this range, it shall be noted in the verification report. 5.2 On each reference block, measure the reference indentation. For each block, the difference between the mean measured value and the certified long diagonal shall not exce
46、ed the greater of 0,5 % and 0,4 m. 5.3 When verifying testing machines used for several test forces, all used forces shall be chosen. One of the forces shall be the lowest force used and the other force shall be chosen within the upper half of those used. For each test force chosen, two different re
47、ference blocks shall be chosen within the range for which the machine is used. The ratio of the hardness values for the two blocks shall be equal to or greater than 2. 5.4 When verifying testing machines used for only one test force, three reference blocks shall be used, uniformly distributed over t
48、he range of the machine. 5.5 On each reference block, five indentations shall be made and measured. The tests shall be carried out in accordance with ISO 4545-1. 5.6 For each reference block, let d 1 , d 2 , , d 5be the values of the measured diagonals of the indentations, arranged in increasing order of magnitude, and 12 5 . 5 dd d d + = (1) 5.7 The repeatability r of the testing machine, under the particular verification conditions
