1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS EN ISO 3953:2011Metallic powders Determination of tap density(ISO 3953:2011)BS EN ISO 3953:2011 BRITISH STANDARDNational forewordThis British Standard is the UK implementation
2、 of EN ISO 3953:2011.It supersedes BS EN ISO 3953:1995 which is withdrawn.The UK participation in its preparation was entrusted to TechnicalCommittee ISE/65, Sintered metal components.A list of organizations represented on this committee can beobtained on request to its secretary.This publication do
3、es not purport to include all the necessaryprovisions of a contract. Users are responsible for its correctapplication. BSI 2011ISBN 978 0 580 71218 0ICS 77.160Compliance with a British Standard cannot confer immunity fromlegal obligations.This British Standard was published under the authority of th
4、eStandards Policy and Strategy Committee on 28 February 2011.Amendments issued since publicationDate Text affectedEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 3953 February 2011 ICS 77.160 Supersedes EN ISO 3953:1995English Version Metallic powders - Determination of tap density (ISO 395
5、3:2011) Poudres mtalliques - Dtermination de la masse volumique aprs tassement (ISO 3953:2011) Metallpulver - Bestimmung der Klopfdichte (ISO 3953:2011) This European Standard was approved by CEN on 31 January 2011. CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stip
6、ulate the conditions for giving this European Standard 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 CEN-CENELEC Management Centre or to any CEN member. This European
7、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 language and notified to the CEN-CENELEC Management Centre has the same status as the official versions. CEN members are the
8、 national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Sw
9、itzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2011 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. N
10、o. EN ISO 3953:2011: EBS EN ISO 3953:2011EN ISO 3953:2011 (E) 3 Foreword This document (EN ISO 3953:2011) has been prepared by Technical Committee ISO/TC 119 “Powder metallurgy“. This European Standard shall be given the status of a national standard, either by publication of an identical text or by
11、 endorsement, at the latest by August 2011, and conflicting national standards shall be withdrawn at the latest by August 2011. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN and/or CENELEC shall not be held responsible for i
12、dentifying any or all such patent rights. This document supersedes EN ISO 3953:1995. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Re
13、public, 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 the United Kingdom. Endorsement notice The text of ISO 3953:2011 has
14、been approved by CEN as a EN ISO 3953:2011 without any modification. BS EN ISO 3953:2011ISO 3953:2011(E) ISO 2011 All rights reserved iiiForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing
15、 International Standards is normally carried out through ISO technical committees. 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 liais
16、on with ISO, also take part in the work. ISO collaborates closely with the 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 te
17、chnical committees is to prepare International Standards. Draft International 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 dr
18、awn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 3953 was prepared by Technical Committee ISO/TC 119, Powder metallurgy, Subcommittee SC 2, Sampling and testing
19、methods for powders (including powders for hardmetals). This fourth edition cancels and replaces the third edition (ISO 3953:1993), of which it constitutes a minor revision. BS EN ISO 3953:2011BS EN ISO 3953:2011INTERNATIONAL STANDARD ISO 3953:2011(E) ISO 2011 All rights reserved 1Metallic powders D
20、etermination of tap density 1 Scope This International Standard specifies a method for the determination of tap density, i.e. the density of a powder that has been tapped into a container under specified conditions. 2 Principle A specified amount of powder in a container is tapped by means of a tapp
21、ing apparatus until no further decrease in the volume of the powder takes place. The mass of the powder divided by its volume after the test gives its tap density. 3 Symbols For the purposes of this document, the symbols in Table 1 apply. Table 1 Symbols Symbol Meaning Unit tTap density g/cm3m Mass
22、of the powder g V Volume of the tapped powder cm34 Apparatus 4.1 Balance, of appropriate capacity to satisfy the requirements shown in Table 2 and of an accuracy to weigh to the nearest 0,1 g. 4.2 Graduated glass cylinder, calibrated to contain 100 cm3, the height of the graduated portion being appr
23、oximately 175 mm. The graduations shall be at 1 cm3intervals, thus allowing a measuring accuracy of 0,5 cm3. Alternatively: Graduated glass cylinder, calibrated to contain 25 cm3, the height of the graduated portion being approximately 135 mm. The graduations shall be at 0,2 cm3intervals. A 25 cm3cy
24、linder shall be used for powders of apparent density higher than 4 g/cm3, in particular for refractory metal powders, but may also be used for powders of lower apparent density. 4.3 Tapping apparatus, which permits the tapping of the graduated cylinder against a firm base. The tapping shall be such
25、that a densification of the powder can take place without any loosening of its surface layers. The stroke shall be 3 mm and the tapping frequency shall be between 100 and 300 taps/min. An example of a tapping apparatus is shown in Figure 1. BS EN ISO 3953:2011ISO 3953:2011(E) 2 ISO 2011 All rights r
26、eservedDimensions in millimetres Key 1 graduated measuring cylinder 2 holder with guide-pin 3 guide-bearing 4 anvil (steel) 5 cam aHeight of stroke. Figure 1 Example of tapping apparatus BS EN ISO 3953:2011ISO 3953:2011(E) ISO 2011 All rights reserved 35 Sampling 5.1 For the quantities of powder req
27、uired for each test, see Table 2. Table 2 Required sample quantities Apparent density g/cm3Cylinder capacity cm3Mass of testportion g 1 to 4 100 100 0,5 7 25 100 0,5 2 to 7 25 50 0,2 0,8 to 2 25 20 0,1 0,8 25 10 0,1 5.2 In general, the powder should be tested in the as-received condition. In certain
28、 instances, the powder may be dried. However, if the powder is susceptible to oxidation, the drying shall take place in a vacuum or in an inert gas. If the powder contains volatile substances, it shall not be dried. 5.3 The test shall be carried out on three test portions, if possible. 6 Procedure 6
29、.1 Clean the inside wall of the graduated cylinder (4.2) with a suitable clean brush or, if necessary, by rinsing with a solvent, such as acetone. If a solvent is used, thoroughly dry the cylinder before re-use. 6.2 Weigh, to the nearest 0,1 g, the mass of the test portion as indicated in Table 2, u
30、sing the balance (4.1). 6.3 Pour the test portion into the graduated cylinder. Take care that a level surface of the powder is formed. Place the cylinder in the tapping apparatus (4.3). Tap the cylinder until no further decrease in the volume of the powder takes place (see Note). NOTE In practice, t
31、he minimum number of taps, N, would be determined such that no further change in volume takes place. For all further tests on the same type of powder, the cylinder would be subjected to 2N taps, except where general experience and acceptance has established a specific number of taps (no less than N
32、taps) as being satisfactory. For fine refractory metal powders, 3 000 taps has been found to be satisfactory for all sizes. 6.4 If the tapped surface is level, read the volume directly. If the tapped surface is not Ievel, determine the tap volume by calculating the mean value between the highest and
33、 the lowest reading of the tapped surface. Read the final volume to the nearest 0,5 cm3when using a 100 cm3cylinder, and to the nearest 0,2 cm3when using a 25 cm3cylinder. BS EN ISO 3953:2011ISO 3953:2011(E) 4 ISO 2011 All rights reserved7 Expression of results The tap density is given by the follow
34、ing equation: tmV = where t, m and V are as defined in Table 1. Report the arithmetical mean of the number of determinations rounded to the nearest 0,1 g/cm3for values up to and including 4 g/cm3, and to the nearest 0,2 g/cm3for values greater than 4 g/cm3. 8 Test report The test report shall includ
35、e the following information: a) a reference to this International Standard, i.e. ISO 3953:2011; b) all details necessary for identification of the test sample; c) the drying procedure, if the powder has been dried; d) the cylinder capacity, mass of the test portion and method used; e) the result obt
36、ained; f) all operations not specified in this International Standard or regarded as optional; g) details of any occurrence which may have affected the result. BS EN ISO 3953:2011This page deliberately left blankThis page deliberately left blankBSI is the independent national body responsible for pr
37、eparing British Standardsand other standards-related publications, information and services. It presents the UK view on standards in Europe and at the international level. It is incorporated by Royal Charter.British Standards Institution (BSI)raising standards worldwideBSI Group Headquarters389 Chis
38、wick High Road London W4 4AL UKTel +44 (0)20 8996 9001Fax +44 (0)20 8996 Standards are updated by amendment or revision. Users of British Stan-dards should make sure that they possess the latest amendments or editions.It is the constant aim of BSI to improve the quality of our products and serv-ice
39、s. We would be grateful if anyone finding an inaccuracy or ambiguity whileusing this British Standard would inform the Secretary of the technical com-mittee responsible, the identity of which can be found on the inside frontcover.Tel: +44 (0)20 8996 9001 Fax: +44 (0)20 8996 7001BSI offers Members an
40、 individual updating service called PLUS which ensuresthat subscribers automatically receive the latest editions of standards.Tel: +44 (0)20 8996 7669 Fax: +44 (0)20 8996 7001Email: Buying standardsYou may buy PDF and hard copy versions of standards directly using acredit card from the BSI Shop on t
41、he website addition all orders for BSI, international and foreign standards publicationscan be addressed to BSI Customer Services.Tel: +44 (0)20 8996 9001 Fax: +44 (0)20 8996 7001Email: In response to orders for international standards, it is BSI policy tosupply the BSI implementation of those that
42、 have been publishedas British Standards, unless otherwise requested.Information on standardsBSI provides a wide range of information on national, Europeanand international standards through its Knowledge Centre.Tel: +44 (0)20 8996 7004 Fax: +44 (0)20 8996 7005Email: Various BSI electronic informati
43、on services are also available whichgive details on all its products and services. Tel: +44 (0)20 8996 7111 Fax: +44 (0)20 8996 7048Email: BSI Subscribing Members are kept up to date with standardsdevelopments and receive substantial discounts on the purchase priceof standards. For details of these
44、and other benefits contact Membership Ad-ministration. Tel: +44 (0)20 8996 7002 Fax: +44 (0)20 8996 7001 Email: Information regarding online access to British Standards via BritishStandards Online can be found at information about BSI is available on the BSI website at www.bsi- subsists in all BSI
45、 publications. BSI also holds the copyright,in the UK, of the publications of the international standardization bodies. Ex-cept as permitted under the Copyright, Designs and Patents Act 1988 no ex-tract may be reproduced, stored in a retrieval system or transmitted in anyform or by any means electro
46、nic, photocopying, recording or otherwise without prior written permission from BSI. This does not preclude the freeuse, in the course of implementing the standard of necessary details such assymbols, and size, type or grade designations. If these details are to be usedfor any other purpose than implementation then the prior written permissionof BSI must be obtained. Details and advice can be obtained from the Copy-right & Licensing Manager.Tel: +44 (0)20 8996 7070Email:
