1、CEN EN*23878 93 = 3404589 0046793 274 EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 23878 April 1993 UDC 669.018.25 : 620.178.152.341 Descriptors: Powder metallurgy, hard metals, mechanical tests, harness tests, Vickers hardness English version Hardmetals - Vickers hardness test (IS0 3878 : 1
2、983) Mtaux-durs - Essai de duret Vickers (IS0 3878 : 1983) Hartmetalle - Vickers-Hrteprfung (IS0 3878 : 1983) This European Standard was approved by CEN on 1993-04-02. CEN members are bound to comply with the CENKENELEC Internal Regulations which stipulate the conditions for giving this European Sta
3、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
4、, 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, Denmark, Finland, Fra
5、nce, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. CEN European Committee for Standardization Comit Europen de Normalisation Europisches Komitee fr Normung Central Secretariat: rue de Stassart 36, B-1050 Brussels O
6、 1993 Copyright reserved to CEN members Ref. No. EN 23878 : 1993 E CEN EN*23878 93 3q04589 00Yb4 LOO Page 2 EN 23878 : 1993 Foreword In 1992, IS0 3878 : 1983 Hardmetals - Vzckers hardness test was submitted to the CEN Primary Questionnaire procedure. Following the positive result of the CEN/CS Propo
7、sal IS0 3878 : 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 standard, either by publication of an identical text or by endorsement, at the latest by October 1993, and conflicting national standards s
8、hall be withdrawn at the latest by October 1993. According to the Internal Regulations of CENKENELEC, the following countries are bound to implement this European Standard: Austria, Belgium, Denmark, Finland, France, Germany) Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal
9、, Spain, Sweden, Switzerland and United Kingdom. NOTE. The Eumpean references to international publications are given in annex ZA (normative). CEN EN*:238?8 93 m 3404589 0046995 047 m 1 Scope and field of application This International Standard specifies the method of Vickers hardness test for hardm
10、etals. Page 3 EN 23878 : 1993 5.3 diagonals to the following accuracy : Measuring device, capable of measuring indentation d 200pm: f0,5%. IS0 146, Metallic materials - Hardness test - Verification of Vickers hardness testing machines HV 0.2 to HV 100.1) IS0 409, Metallic materials - Hardness test -
11、 Tables of Vickers hardness values for use in tests made on flat surfaces - Part 1 : HV 5 to HV 100. - Part 2 : HV 0,2 to less than HV 5. IS0 4505, Hardmetals - Metallographic determination of porosity and uncombimd carbon. IS0 6507, Metallic materials - Hardness test - Vickers test - Part 1 : HV 5
12、to HV 100. - Part 2 : HV 0.2 to less than HV 5. 3 Principle See IS0 6507/1 and IS0 6507/2. 4 Symbols and designations See IS0 6507/1 and IS0 6507/2. 5 Apparatus 5.1 Testing machine, capable of applying a predetermined force or forces within the range of 9,807 N to 490.3 N (HV 1 to HV 501, in accorda
13、nce with IS0 146. 5.2 Indenter, a diamond in the form of a right pyramid with a square base, in accordance with IS0 146. 6 Test pieces 6.1 the test piece shall be not less than 0,2 mm. The thickness of the layer removed from the surface of The test shall be carried out on a surface which is free fro
14、m foreign matter and, in particular, completely free from lubricants. The test surface shall be polished in accordance with IS0 4505. Preparation shall be carried out in such a way that any altera- tion of the surface hardness, for example due to heat or cold working, is minimized. When determining
15、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 least 1 mm thick. The thickness of the test piece shall be sufficient to allow the test to be carried out without breaking or
16、 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. 7 Procedure 7.1 The test force shall be within the range of 9,807 N (HV 1) to W,3
17、 N (HV 501, the preferred force being 294.2 N (HV 301. 7.2 The test piece shall be placed firmly on a rigid support. The contact surfaces shall be clean and free from foreign mat- ter. It is important that the test piece is placed firmly on the support so that displacement cannot occur during the te
18、st. 1) At present at the stage of draft. (Revision of IS0 146.) CEN ENS23878 93 3404589 0046996 T83 Page 4 EN 23878 : 1993 7.3 Force the indenter without shock or vibration perpen- dicularly into the suriace to be tested until the applied force at- tains the specified value. The time from the initia
19、l application of force until the full test force is reached shall not be less than 2 s nor greater than 8 s. The duration of the test force shall be 10 to 15s. 7.4 Throughout the test, the apparatus shall be protected from shock or vibration. 7.5 If possible, at least three hardness determinations s
20、hall be made on the test piece. 7.6 The distance between the centre of any indentation and the edge of the test piece shall be at least 2,5 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
21、 indenta- tion. If two adjacent indentations differ in size, 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 i
22、ndenter. If the examination of the indenter confirms this, then the test shall be rejected and the indenter renewed. 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 Attention is drawn to IS0 40911
23、 and 40912, which con- tains 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 nearest 10 HV. 9 Test report The test report shall include the following information : a) a reference to this In
24、ternational Standard; b) all details necessary for identification of the test sample; cl result obtained; di all operations not specified by this International Standard, or regarded as optional; e) details of any occurrence which may have affected the result. . NOTE - There is no general process for
25、 accurately converting Vickers hardness into other scales of hardness. These conversions, therefore, should be avoided, unless a reliable basis for the conversion can be ob- tained by comparison tests. CEN EN*:23878 93 m 3404589 0046997 9LT m Page 5 EN 23878 : 1993 Annex ZA (normative) Normative ref
26、erences to international publications 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.
27、 For dated references, subsequent 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 IS0 14
28、6 IS0 409-1 IS0 409-2 IS0 4505 IS0 6507-1 IS0 6507-2 EN/HD Year - - Metallic materials - Hardness test - Verifi- cation of Vickers hardness testing machines HV 0,2 to HV 100 - Metallic materials - Hardness test - Tables of Vickers hardness values for use in tests made on flat surfaces - Part 1 : HV
29、5 to HV 1 O0 - Metallic materials - Hardness test - Tables of Vickers hardness values for use in tests made on flat surfaces - Part 2: HV 0,2 to less than HV 5 Hardmetals - Metallographic determination of porosity and uncombined carbon EN 24505 - Metallic materials - Hardness test - Vickers test - Part 1: HV 5 to HV 100 - Metallic materials - Hardness test - Vickers test - Part 2: HV 0,2 to less than HV 5 -
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