1、BS ISO 9649:2016 Metallic materials Wire Reverse torsion test BSI Standards Publication WB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06BS ISO 9649:2016 BRITISH STANDARD National foreword This British Standard is the UK implementation of ISO 9649:2016. The UK participation in its preparation
2、 was entrusted to Technical Committee ISE/101/2, Ductility 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 contract. Users are responsible for its correct applic
3、ation. The British Standards Institution 2016. Published by BSI Standards Limited 2016 ISBN 978 0 580 85214 5 ICS 77.040.10 Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard was published under the authority of the Standards Policy and Strategy C
4、ommittee on 31 May 2016. Amendments issued since publication Date Text affectedBS ISO 9649:2016 ISO 2016 Metallic materials Wire Reverse torsion test Matriaux mtalliques Fils Essai de torsion alterne INTERNATIONAL STANDARD ISO 9649 Second edition 2016-05-15 Reference number ISO 9649:2016(E)BS ISO 96
5、49:2016ISO 9649:2016(E)ii ISO 2016 All rights reserved COPYRIGHT PROTECTED DOCUMENT ISO 2016, Published in Switzerland All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including
6、 photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Ch. de Blandonnet 8 CP 401 CH-1214 Vernier, Geneva, Switzerland Tel.
7、+41 22 749 01 11 Fax +41 22 749 09 47 copyrightiso.org www.iso.orgBS ISO 9649:2016ISO 9649:2016(E)Foreword iv 1 Scope . 1 2 Symbols and designations 1 3 Principle 1 4 Testing equipment 2 5 Test piece 2 6 Test conditions . 3 7 Procedure. 3 8 Test report . 3 Bibliography 4 ISO 2016 All rights reserved
8、 iii Contents PageBS ISO 9649:2016ISO 9649:2016(E) 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 committees. Eac
9、h 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 Internation
10、al Electrotechnical 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
11、 types of ISO documents 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 no
12、t be held responsible 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 in
13、formation given for the 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) se
14、e the following URL: Foreword - Supplementary information The committee responsible for this document is ISO/TC 164, Mechanical testing of metals, Subcommittee SC 2, Ductility testing. This second edition cancels and replaces the first edition (ISO 9649:1990), which has been technically revised.iv I
15、SO 2016 All rights reservedBS ISO 9649:2016INTERNATIONAL ST ANDARD ISO 9649:2016(E) Metallic materials Wire Reverse torsion test 1 Scope This International Standard specifies a method for determining the ability of metallic wire of diameter dimension from 0,3 mm to 10,0 mm inclusive to undergo plast
16、ic deformation during reverse torsion. This test is used to detect surface defects, as well as to assess ductility. 2 Symbols and designations The symbols and designations used in the reverse torsion test of wires are shown in Figure 1 and specified in Table 1. 1 Key 1 grip Figure 1 Reverse torsion
17、test of wires Table 1 Symbols and designations Symbol Designation Unit d Diameter of a round wire mm L Free length between grips mm N 1 Number of turns in one direction N 2 Number of turns in the opposite direction 3 Principle A test piece of wire is twisted a specified number of turns through 360 a
18、round its own axis in one direction, and then a specified number of turns through 360 in the opposite direction. ISO 2016 All rights reserved 1BS ISO 9649:2016ISO 9649:2016(E) 4 Testing equipment 4.1 The grips shall have a minimum hardness of 55HRC to provide rigidity and/or resistance to abrasion.
19、The grip shall be arranged in the testing machine in such a way that, during testing, they remain on the same axis and do not apply any bending force to the piece. One of the grips shall be capable of being rotated around the axis of the test piece in two opposite directions while the other shall no
20、t be subject to any angular deflection, except for such deflection as may be necessary to measure the torque. The distance between the grips shall be capable of adjustment for different test piece lengths. 4.2 The machine shall be constructed so that a change in length between the grips, caused by d
21、eformation of the test piece during the test, is not prevented. The machine shall be constructed so that an appropriate tensile stress (see 7.1) may be applied to the test piece. 4.3 The testing speed shall be able to be adjusted, and the number of turns shall be recorded. 4.4 A protective shield sh
22、all be provided to protect the operator from flying fragments in cases when the wire breaks into more than two pieces. 5 Test piece 5.1 The length of wire to be used as the test piece shall be as straight as possible. If straightening is necessary, it shall be done by using suitable methods. During
23、straightening, the surface of the wire shall not be damaged and the test piece shall not be subject to any twisting. Wire with a localized sharp curvature or kink shall not be used in the test. 5.2 Unless otherwise specified in the relevant standard, the nominal free length between the grips (L) of
24、the test piece shall be as given in Table 2. When testing for surface defects, a fixed free length between grips may be used. This length shall be as specified in the relevant standard and shall be stated in the test report. Table 2 Dependence of free length between the grips on nominal diameter of
25、the wire Nominal diameter d mm Free length between grips L mm (nominal) 0,3 d 1,0 1,0 d 5,0 5,0 d 10,0 200d 100d a 50d b a 50d may be used by special agreement. b 30d may be used by special agreement.2 ISO 2016 All rights reservedBS ISO 9649:2016ISO 9649:2016(E) 6 Test conditions In general, the tes
26、t is carried out at an ambient temperature between 10 C and 35 C. Tests carried out under controlled conditions, where required, shall be made at a temperature of (23 5) C. 7 Procedure 7.1 Place the test piece in the testing machine in such a way that its longitudinal axis coincides with the axis of
27、 the grips and so that it remains straight during the test. Unless otherwise specified, this may be ensured by applying to the test piece a constant tensile stress not exceeding 2 % of the nominal tensile strength of the wire. 7.2 After placing the test piece in the testing machine, rotate one grip
28、at a speed not exceeding 1 turn per second (or not exceeding 0,5 turns per second when the diameter d is 5 mm or greater) through the number of turns, N 1 , in one direction and then the other number of turns, N 2 , in the opposite direction. In general, N 1and N 2are specified in the relevant stand
29、ard. One turn comprises 360. After the test, the free length of wire between the grips shall be examined by eyes unless otherwise specified in the relevant standard. 7.3 If the number of turns, N 2 , meets the requirement of the relevant standard, the test piece is considered as having passed the te
30、st. If the number of turns, N 2 , reached does not meet the requirement of the relevant standard and the failure is within a distance of 2d from the grip, the test shall be considered invalid and shall be repeated. NOTE There is an example for this test in ISO 8458-3. 8 Test report The test report s
31、hall include the following information: a) a reference to this International Standard, i.e. ISO 9649; b) all details necessary for the identification of the test piece (type of the material, heat number, etc.); c) the diameter d of the test piece; d) all details regarding the test piece preparation
32、(method of straightening, etc.); e) the test conditions (the free length between the grips, the tensile stress applied, test speed, etc.); f) the number of turns (N 1 , N 2 ). ISO 2016 All rights reserved 3BS ISO 9649:2016ISO 9649:2016(E) Bibliography 1 ISO 8458-3, Steel wire for mechanical springs
33、Part 3: Oil-hardened and tempered wire4 ISO 2016 All rights reservedBS ISO 9649:2016BS ISO 9649:2016ISO 9649:2016(E) ISO 2016 All rights reserved IC S 77.040.10 Price based on 4 pagesThis page deliberately left blankBSI is the national body responsible for preparing British Standards and other stand
34、ards-related publications, information and services. BSI is incorporated by Royal Charter. British Standards and other standardization products are published by BSI Standards Limited. British Standards Institution (BSI) About us We bring together business, industry, government, consumers, innovators
35、 and others to shape their combined experience and expertise into standards -based solutions. The knowledge embodied in our standards has been carefully assembled in a dependable format and refined through our open consultation process. Organizations of all sizes and across all sectors choose standa
36、rds to help them achieve their goals. Information on standards We can provide you with the knowledge that your organization needs to succeed. Find out more about British Standards by visiting our website at or contacting our Customer Services team or Knowledge Centre. Buying standards You can buy a
37、nd download PDF versions of BSI publications, including British and adopted European and international standards, through our website at where hard copies can also be purchased. If you need international and foreign standards from other Standards Development Organizations, hard copies can be ordere
38、d from our Customer Services team. Copyright in BSI publications All the content in BSI publications, including British Standards, is the property of and copyrighted by BSI or some person or entity that owns copyright in the information used (such as the international standardization bodies) and has
39、 formally licensed such information to BSI for commercial publication and use. Save for the provisions below, you may not transfer, share or disseminate any portion of the standard to any other person. You may not adapt, distribute, commercially exploit, or publicly display the standard or any porti
40、on thereof in any manner whatsoever without BSIs prior written consent. Storing and using standards Standards purchased in soft copy format: A British Standard purchased in soft copy format is licensed to a sole named user for personal or internal company use only. The standard may be stored on more
41、 than 1 device provided that it is accessible by the sole named user only and that only 1 copy is accessed at any one time. A single paper copy may be printed for personal or internal company use only. Standards purchased in hard copy format: A British Standard purchased in hard copy format is for p
42、ersonal or internal company use only. It may not be further reproduced in any format to create an additional copy. This includes scanning of the document. If you need more than 1 copy of the document, or if you wish to share the document on an internal network, you can save money by choosing a subsc
43、ription product (see Subscriptions). Reproducing extracts For permission to reproduce content from BSI publications contact the BSI Copyright & Licensing team. Subscriptions Our range of subscription services are designed to make using standards easier for you. For further information on our subscri
44、ption products go to With British Standards Online (BSOL) youll have instant access to over 55,000 British and adopted European and international standards from your desktop. Its available 24/7 and is refreshed daily so youll always be up to date. You can keep in touch with standards developments a
45、nd receive substantial discounts on the purchase price of standards, both in single copy and subscription format, by becoming a BSI Subscribing Member. PLUS is an updating service exclusive to BSI Subscribing Members. You will automatically receive the latest hard copy of your standards when theyre
46、revised or replaced. To find out more about becoming a BSI Subscribing Member and the benefits of membership, please visit With a Multi-User Network Licence (MUNL) you are able to host standards publications on your intranet. Licences can cover as few or as many users as you wish. With updates supp
47、lied as soon as theyre available, you can be sure your documentation is current. For further information, email . Revisions Our British Standards and other publications are updated by amendment or revision. We continually improve the quality of our products and services to benefit your business. If
48、you find an inaccuracy or ambiguity within a British Standard or other BSI publication please inform the Knowledge Centre. Useful Contacts Customer Services Tel: +44 345 086 9001 Email (orders): Email (enquiries): Subscriptions Tel: +44 345 086 9001 Email: Knowledge Centre Tel: +44 20 8996 7004 Email: Copyright & Licensing Tel: +44 20 8996 7070 Email: NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BSI Group Headquarters 389 Chiswick High Road London W4 4AL UK BSI Back Cover.indd 1 27/01/2016 14:20
