1、BSI Standards PublicationBS EN ISO 6508-3:2015Metallic materials Rockwell hardness testPart 3: Calibration of reference blocksBS EN ISO 6508-3:2015 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of EN ISO 6508-3:2015. It supersedes BS EN ISO 6508-3:2005 which iswithd
2、rawn.The UK participation in its preparation was entrusted to Technical Committee ISE/101/5, Indentation hardness testing.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a c
3、ontract. Users are responsible for its correct application. The British Standards Institution 2015.Published by BSI Standards Limited 2015ISBN 978 0 580 79171 0 ICS 77.040.10 Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under th
4、e authority of the Standards Policy and Strategy Committee on 31 March 2015.Amendments/corrigenda issued since publicationDate T e x t a f f e c t e dEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 6508-3 March 2015 ICS 77.040.10 Supersedes EN ISO 6508-3:2005English Version Metallic materia
5、ls - Rockwell hardness test - Part 3: Calibration of reference blocks (ISO 6508-3:2015) Matriaux mtalliques - Essai de duret Rockwell - Partie 3: talonnage des blocs de rfrence (ISO 6508-3:2015) Metallische Werkstoffe - Hrteprfung nach Rockwell - Teil 3: Kalibrierung von Hrtevergleichsplatten (ISO 6
6、508-3:2015) This European Standard was approved by CEN on 10 January 2015. CEN members are bound to 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 bibliog
7、raphical references concerning such national standards may be obtained on application to the CEN-CENELEC 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 responsib
8、ility of a CEN member into its own language and notified to the CEN-CENELEC Management Centre has the 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 Republi
9、c of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALIS
10、ATION EUROPISCHES KOMITEE FR NORMUNG CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2015 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 6508-3:2015 EBS EN ISO 6508-3:2015EN ISO 6508-3:2015 (E) 3 Foreword This
11、 document (EN ISO 6508-3:2015) has been prepared by Technical Committee ISO/TC 164 “Mechanicaltesting of metals“ in collaboration with Technical Committee ECISS/TC 101 “Test methods for steel (otherthan chemical analysis)” the secretariat of which is held by AFNOR. This European Standard shall be gi
12、ven the status of a national standard, either by publication of an identicaltext or by endorsement, at the latest by September 2015, and conflicting national standards shall bewithdrawn at the latest by September 2015. Attention is drawn to the possibility that some of the elements of this document
13、may be the subject of patentrights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 6508-3:2005. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the followingcountries are bound
14、 to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, CzechRepublic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,Ro
15、mania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 6508-3:2015 has been approved by CEN as EN ISO 6508-3:2015 without any modification. BS EN ISO 6508-3:2015ISO 6508-3:2015(E)Foreword iv1 Scope . 12 Normative references 13 Manufac
16、ture of reference blocks . 14 Calibration machine and calibration indenter . 24.1 General . 24.2 Calibration machine . 24.3 Calibration diamond indenter . 24.4 Calibration ball indenter . 45 Calibration procedure . 46 Number of indentations 57 Uniformity of hardness 58 Marking 69 Calibration certifi
17、cate . 710 Validity 7Annex A (normative) Uniformity of reference blocks 8Annex B (informative) Uncertainty of the mean hardness value of hardness-reference blocks 10Annex C (normative) Requirements for reference diamond indenters 16Bibliography .17 ISO 2015 All rights reserved iiiContents PageBS EN
18、ISO 6508-3:2015ISO 6508-3:2015(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 informationThe committee responsible for this document is ISO/TC 164, Mechanical testing of metals, Subcommittee SC 3, Hardness testing.This third edition cancels and replaces the second edition (ISO 6508-3:2005), which has been technically revised.ISO 6508 consists of the fol
25、lowing parts, under the general title Metallic materials Rockwell hardness test: Part 1: Test method Part 2: Verification and calibration of testing machines and indenters Part 3: Calibration of reference blocksiv ISO 2015 All rights reservedBS EN ISO 6508-3:2015Metallic materials Rockwell hardness
26、test Part 3: Calibration of reference blocks1 ScopeThis part of ISO 6508 specifies a method for the calibration of reference blocks to be used for the indirect and daily verification of Rockwell hardness testing machines, as specified in ISO 6508-2:2015.Attention is drawn to the fact that the use of
27、 hard metal for ball indenters is considered to be the standard type of Rockwell indenter ball. Steel indenter balls can be used only when complying with ISO 6508-1:2015, Annex A.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are i
28、ndispensable 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 376, Metallic materials Calibration of force-proving instruments used for the verification of uniaxial
29、testing machinesISO 6508-1:2015, Metallic materials Rockwell hardness test Part 1: Test methodISO 6508-2:2015, Metallic materials Rockwell hardness test Part 2: Verification and calibration of testing machines and indenters3 Manufacture of reference blocks3.1 The block shall be specially manufacture
30、d for use as a hardness-reference block.NOTE Attention is drawn to the need to use a manufacturing process, which will give the necessary homogeneity, stability of structure, and uniformity of surface hardness.3.2 Each hardness reference block shall be of a thickness not less than 6 mm. To minimize
31、the effect of hardness change with increasing number of indents, thicker blocks should be used.3.3 The reference blocks shall be free of magnetism. It is recommended that the manufacturer ensure that the blocks, if made of steel, have been demagnetized at the end of the manufacturing process (before
32、 calibration).3.4 The deviation from surface flatness of the top and bottom surfaces shall be 0,01 mm. The bottom of the blocks shall not be convex. The deviation from parallelism of the top and bottom surfaces shall be 0,02 mm per 50 mm.3.5 The test surface and lower surface shall be free from dama
33、ge, such as notches, scratches, oxide layers, etc., which can interfere with the measurement of the indentations. The surface roughness, Ra, shall not exceed 0,000 3 mm for the test surface and 0,000 8 mm for the bottom surface. Sampling length is l = 0,8 mm (see ISO 4287:1997, 3.1.9).INTERNATIONAL
34、STANDARD ISO 6508-3:2015(E) ISO 2015 All rights reserved 1BS EN ISO 6508-3:2015ISO 6508-3:2015(E)3.6 To verify that no material is subsequently removed from the reference block, the thickness at the time of calibration shall be marked on it, to the nearest 0,1 mm, or an identifying mark shall be mad
35、e on the test surface see 8.1 e).4 Calibration machine and calibration indenter4.1 General4.1.1 Calibrations and verifications of Rockwell calibration machines and calibration indenters shall be carried out at a temperature of (23 5) C.4.1.2 The instruments used for calibration shall be traceable to
36、 national standards.4.2 Calibration machine4.2.1 In addition to fulfilling the general conditions specified in ISO 6508-2:2015, Clause 3, the calibration machine shall also meet the requirements given in 4.2.2, 4.2.3, 4.2.4, 4.2.5, and 4.2.6.4.2.2 The machine shall be directly verified in intervals
37、not exceeding 12 months. Direct verification involves calibration and verification of the following:a) test force;b) measuring system;c) testing cycle; if this is not possible, at least the force versus time behaviour.4.2.3 The test force shall be measured by means of an elastic proving device (acco
38、rding to ISO 376) class 0,5 or better and calibrated for reversibility, or by another method having the same or better accuracy.Evidence should be available to demonstrate that the output of the force-proving device does not vary by more than 0,1 % in a period of 1 s to 30 s, following a stepped cha
39、nge in force.4.2.4 Each test force shall be measured and shall agree with the nominal preliminary test force, F0, to within 0,2 % and the nominal total test force, F, to within 0,1 %.4.2.5 The measuring system shall have a resolution of 0,000 1 mm and a maximum expanded uncertainty of 0,000 2 mm, wh
40、en calculated with a confidence level of 95 % over its working range.4.2.6 The testing cycle shall be timed with an uncertainty less than 0,5 s and shall conform to the testing cycle of Clause 5.4.3 Calibration diamond indenter4.3.1 The geometric shape and performance of calibration diamond indenter
41、s shall be calibrated as defined below. Direct verification of the geometric shape shall be made before first use and at a frequency of no greater than five years. Verification of the indenter performance, as specified in 4.3.3, shall be made before first use and at a frequency of no greater than 12
42、 months.4.3.2 The diamond indenter shall be measured on at least eight unique axial section planes equidistant from each other (e.g. the eight cross-sections will be spaced approximately 22,5 apart at 0, 22,5, 45, 67,5, 90, 112,5, 135, 157,5), and shall meet the following requirements:2 ISO 2015 All
43、 rights reservedBS EN ISO 6508-3:2015ISO 6508-3:2015(E)a) The cone angle shall be measured adjacent to the blend. The diamond cone shall have a mean included angle of (120 0,1). In each measured axial section, the included angle shall be (120 0,17).b) The mean deviation from straightness of the gene
44、ratrix of the diamond cone adjacent to the blend shall not exceed 0,000 5 mm over a minimum length of 0,4 mm. In each measured section, the deviation shall not exceed 0,000 7 mm.c) The radius of the spherical tip of the diamond shall be measured adjacent to the blend. The tip shall have a mean radiu
45、s of (0,200 0,005) mm. In each measured section, the radius shall be within (0,200 0,007) mm and local deviations from a true radius shall not exceed 0,002 mm.NOTE The tip of the diamond indenter is usually not truly spherical, but often varies in radius across its surface. Depending on the crystall
46、ographic orientation of the diamond stone with respect to the indenter axis, diamond tends to preferentially polish away more easily or with more difficulty at the tip, producing an increasingly flat or sharp surface in the central indenter axis region. The sphericity of the diamond tip can be bette
47、r evaluated by measuring multiple measurement windows of varying width. The measurement window would be bounded by widths measured along a line normal to the indenter axis. For example, the following window sizes can be evaluated: between 80 m from the indenter axis; between 60 m from the indenter a
48、xis; between 40 m from the indenter axis.d) The surfaces of the cone and the spherical tip shall blend in a smooth tangential manner. The location where the spherical tip and the cone of the diamond blend together will vary depending on the values of the tip radius and cone angle. Ideally for a perf
49、ect indenter geometry, the blend point is located at 100 m from the indenter axis measured along a line normal to the indenter axis. To avoid including the blend area in the measurement of the tip radius and cone angle, the portion of the diamond surface between 90 m and 110 m should be ignored.e) The inclination of the axis of the diamond cone to the axis of the indenter holder (normal to the seating surface) shall be within 0,3.4.3.3 Calibration diamond indenters shall be performance verified by
