1、BRITISH STANDARD BSEN 23878:1993 ISO3878:1983 Hardmetals Vickers hardness test The European Standard EN23878:1993 has the status of a British Standard UDC669.018.25:620.178.152.341BSEN23878:1993 This British Standard, having been prepared under the directionof the Iron and Steel Standards Policy Com
2、mittee, waspublished under the authorityof the Standards Boardand comes into effect on 15June1993 BSI 07-1999 The following BSI references relate to the work on this standard: Committee reference ISM/65 Special announcement in BSINews, January1993 ISBN 0 580 21913 5 Cooperating organizations The Eur
3、opean Committee for Standardization (CEN), under whose supervision this European Standard was prepared, comprises the national standards organizations of the following countries: Austria Oesterreichisches Normungsinstitut Belgium Institut belge de normalisation Denmark Dansk Standardiseringsraad Fin
4、land Suomen Standardisoimisliito, r.y. France Association franaise de normalisation Germany Deutsches Institut fr Normung e.V. Greece Hellenic Organization for Standardization Iceland Technological Institute of Iceland Ireland National Standards Authority of Ireland Italy Ente Nazionale Italiano di
5、Unificazione Luxembourg Inspection du Travail et des Mines Netherlands Nederlands Normalisatie-instituut Norway Norges Standardiseringsforbund Portugal Instituto Portugus da Qualidade Spain Asociacin Espaola de Normalizacin y Certificacin Sweden Standardiseringskommissionen i Sverige Switzerland Ass
6、ociation suisse de normalisation United Kingdom British Standards Institution Amendments issued since publication Amd. No. Date CommentsBSEN23878:1993 BSI 07-1999 i Contents Page Cooperating organizations Inside front cover National foreword ii Foreword 2 1 Scope and field of application 3 2 Referen
7、ces 3 3 Principle 3 4 Symbols and designations 3 5 Apparatus 3 6 Test pieces 3 7 Procedure 3 8 Expression of results 4 9 Test report 4 Annex ZA (normative) Normative references to international publicationswiththeir relevant European publications 5 National annex NA (informative) Relevant informatio
8、n from ISO146, ISO6507-1 and ISO6507-2 6 National annex NB (informative) Committees responsible Inside back cover National annex NC (informative) Cross-reference Inside back cover Figure NA.1 8 Figure NA.2 8 Table NA.1 6 Table NA.2 7BSEN23878:1993 ii BSI 07-1999 National foreword This British Standa
9、rd has been prepared under the direction of the Iron and Steel Standards Policy Committee and is the English language version of EN23878:1993 Hardmetals Vickers hardness test, published by the European Committee for Standardization (CEN). It is identical with ISO3878:1983, prepared by Technical Comm
10、ittee119, Powder metallurgy, of the International Organization for Standardization (ISO) with the active participation of the UK. This British Standard supersedes BS5600-4.6:1987, which is withdrawn and from which it differs by the addition of Annex ZA. A British Standard does not purport to include
11、 all the necessary provisions of a contract. Users of British Standards are responsible for their 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, pagesi a
12、ndii, theEN title page, pages2 to8, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN23878 A
13、pril1993 UDC669.018.25:620.178.152.341 Descriptors: Powder metallurgy, hard metals, mechanical tests, harness tests, Vickers hardness English version Hardmetals Vickers hardness test (ISO3878:1983) Mtaux-durs Essai de duret Vickers (ISO3878:1983) Hartmetalle Vickers-Hrteprfung (ISO3878:1983) This Eu
14、ropean Standard was approved by CEN on1993-04-02. 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 bibliographical references conce
15、rning 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, German). A version in any other language made by translation under the responsibility of a CEN member into its own
16、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, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland
17、and UnitedKingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels 1993 Copyright reserved to CEN members Ref. No. EN23878:1993EEN23878:1993 BSI 07-1999 2 Foreword In1992, ISO3878:1983 H
18、ardmetals Vickers hardness test was submitted to the CEN Primary Questionnaire procedure. Following the positive result of the CEN/CS Proposal ISO3878:1983 was submitted to the Formal Vote. The result of the Formal Vote was positive. This European Standard shall be given the status of a national sta
19、ndard, either by publication of an identical text or by endorsement, at the latest by October1993, and conflicting national standards shall be withdrawn at the latest by October1993. According to the Internal Regulations of CEN/CENELEC, the following countries are bound to implement this European St
20、andard: Austria, Belgium, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and UnitedKingdom. NOTEThe European references to international publications are given inAnnex ZA (normative).EN23878:1993 BSI 07-1999 3
21、 1 Scope and field of application This International Standard specifies the method of Vickers hardness test for hardmetals. 2 References ISO146, Metallic materials Hardness test Verification of Vickers hardness testing machines HV0,2 to HV100 1) . ISO409, Metallic materials Hardness test Tables of V
22、ickers hardness values for use in tests made on flat surfaces. Part1: HV5 to HV100; Part2: HV0,2 to less than HV5. ISO4505, Hardmetals Metallographic determination of porosity and uncombined carbon. ISO6507, Metallic materials Hardness test Vickers test. Part1: HV5 to HV100; Part2: HV0,2 to less tha
23、n HV5. 3 Principle SeeISO6507-1 and ISO6507-2. 4 Symbols and designations SeeISO6507-1 and ISO6507-2. 5 Apparatus 5.1 Testing machine, capable of applying a predetermined force or forces within the range of9,807N to490,3N (HV1 to HV50), in accordance with ISO146. 5.2 Indenter, a diamond in the form
24、of a right pyramid with a square base, in accordance with ISO146. 5.3 Measuring device, capable of measuring indentation diagonals to the following accuracy: d1004m: 0,24m; 1004mu d2004m: 1,04m; dW 2004m: 0,5%. 6 Test pieces 6.1 The thickness of the layer removed from the surface of the test piece s
25、hall be not less than0,2mm. The test shall be carried out on a surface which is free from foreign matter and, in particular, completely free from lubricants. The test surface shall be polished in accordance with ISO4505. Preparation shall be carried out in such a way that any alteration of the surfa
26、ce hardness, for example due to heat or cold working, is minimized. When determining the hardness of a test piece with a curved surface, a flat surface shall be prepared on the test piece on which to carry out the test. 6.2 The prepared test piece shall be at least1mm thick. The thickness of the tes
27、t piece shall be sufficient to allow the test to be carried out without breaking or deforming the test piece under the chosen force. For test pieces of small cross-section or of irregular shape, it may be necessary to provide some form of additional support, for example mounting in plastic material.
28、 7 Procedure 7.1 The test force shall be within the range of9,807N (HV1) to490,3N (HV50), the preferred force being294,2N (HV30). 7.2 The test piece shall be placed firmly on a rigid support. The contact surfaces shall be clean and free from foreign matter. It is important that the test piece is pla
29、ced firmly on the support so that displacement cannot occur during the test. 7.3 Force the indenter without shock or vibration perpendicularly into the surface to be tested until the applied force attains the specified value. The time from the initial application of force until the full test force i
30、s reached shall not be less than2s nor greater than8s. The duration of the test force shall be10 to15s. 7.4 Throughout the test, the apparatus shall be protected from shock or vibration. 7.5 If possible, at least three hardness determinations shall be made on the test piece. 7.6 The distance between
31、 the centre of any indentation and the edge of the test piece shall be at least2,5 times the mean diagonal of the indentation. The distance between the centres of two adjacent indentations shall be at least three times the mean diagonal of the indentation. If two adjacent indentations differ in size
32、, the spacing shall be based on the mean diagonal of the larger indentation. 7.7 The satisfactory condition of the indenter shall be verified frequently. Any irregularities in the shape of the indentation may indicate poor condition of the indenter. If the examination of the indenter confirms this,
33、then the test shall be rejected and the indenter renewed. 1) At present at the stage of draft. (Revision of ISO146.)EN23878:1993 4 BSI 07-1999 7.8 Measure the lengths of the two diagonals. The arithmetical mean of the two readings shall be taken for the calculation of the Vickers hardness. 7.9 Atten
34、tion is drawn to ISO409-1 and409-2, which contains conversion tables for use in tests made on flat surfaces. 8 Expression of results Report the arithmetical mean of the hardness values obtained, rounded to the nearest10HV. 9 Test report The test report shall include the following information: a) a r
35、eference to this International Standard; b) all details necessary for identification of the test sample; c) result obtained; d) all operations not specified by this International Standard, or regarded as optional; e) details of any occurrence which may have affected the result. NOTEThere is no gener
36、al process for accurately converting Vickers hardness into other scales of hardness. These conversions, therefore, should be avoided, unless a reliable basis for the conversion can be obtained by comparison tests.EN23878:1993 BSI 07-1999 5 Annex ZA (normative) Normative references to international p
37、ublications with their relevant European publications This European Standard incorporates by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, sub
38、sequent amendments to or revisions of any of these publications apply to this European Standard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). Publication Year Title EN/HD Year ISO146 Met
39、allic materials Hardness test Verification of Vickers hardness testing machines HV0,2 to HV100 ISO409-1 Metallic materials Hardness test Tables of Vickers hardness values for use in tests made on flat surfaces Part1:HV5 to HV100 ISO409-2 Metallic materials Hardness test Tables of Vickers hardness va
40、lues for use in tests made on flat surfaces Part2:HV0,2 to less than HV5 ISO4505 Hardmetals Metallographic determination of porosity and uncombined carbon EN24505 ISO6507-1 Metallic materials Hardness test Vickers test Part1:HV5 to HV100 ISO6507-2 Metallic materials Hardness test Vickers test Part2:
41、HV0,2 to less than HV5 BSEN23878:1993 6 BSI 07-1999 National annex NA (informative) Relevant information from ISO146, ISO6507-1 and ISO6507-2 NA.1 Introduction In clauses3, 4 and5 of this standard, reference is made to ISO6507-1, ISO6507-2 and ISO146, for which there are no corresponding British Sta
42、ndards. In order to ensure that the required information is readily accessible to the user, relevant extracts from these international standards are reproduced in the succeeding clauses. NA.2 Principle Forcing a diamond indenter in the form of a right pyramid with a square base and with a specified
43、angle between opposite faces at the vertex into the surface of a test piece and measuring the diagonals of the indentation left in the surface after removal of the test force, F. (SeeFigure NA.1). The Vickers hardness is proportional to the quotient obtained by dividing the test force by the sloping
44、 area of the identation which is assumed to be a right pyramid with a square base, and having at the vertex the same angle as the indenter. NA.3 Symbols and designations Table NA.1 NA.4 Verification of the test force NA.4.1 Each test force used (chosen from Table NA.2) within the working range of th
45、e testing machine, shall be measured, and, whenever applicable, this shall be done at not less than three positions of the plunger uniformly spaced throughout its range of movement during testing. NA.4.2 The test force shall be measured by one of the following two methods: a) measuring by means of a
46、n elastic proving device previously calibrated to an accuracy of 0,2%. b) balancing against a force, accurate to 0,2% applied by means of standardized masses with mechanical advantage. NA.4.3 Three readings shall be taken for each test force at each position of the plunger. Immediately before each r
47、eading is taken, the plunger shall have been moved in the same direction as during testing. NA.4.4 Each measurement of the force shall be within 1,0% of the nominal value of the test force, as given in Table NA.2. Symbol Designation F d HV Angle between the opposite faces at the vertex of the pyrami
48、dal indenter(136 ) Test force, in newtons Arithmetic mean, in millimetres, of the two diagonals d 1and d 2 Vickers hardness NOTEConstant Constant Test force Surface area of indentation - = 0,102 2F 136 2 - sin d 2 -0,189 1 F d 2 - = 1 g n - = 1 9,806 65 -0,102 =BSEN23878:1993 BSI 07-1999 7 Table NA.
49、2 NA.5 Verification of the indenter NA.5.1 The four faces of the square-based diamond pyramid shall be polished and free from surface defects. NA.5.2 The verification of the shape of the indenter can be made by direct measurement or by measurement of its projection on a screen. NA.5.3 The angle between the o
