《BS-ISO-7800-2003.pdf》由会员分享，可在线阅读，更多相关《BS-ISO-7800-2003.pdf（14页珍藏版）》请在三一文库上搜索。
1、BRITISH STANDARD BS ISO 7800:2003 Metallic materials Wire Simple torsion test ICS 77.040.10 ? Licensed Copy: London South Bank University, London South Bank University, Thu Mar 01 07:01:29 GMT+00:00 2007, Uncontrolled Copy, (c) BSI BS ISO 7800:2003 This British Standard was published under the autho
2、rity of the Standards Policy and Strategy Committee on 9 September 2003 BSI 9 September 2003 ISBN 0 580 42597 5 National foreword This British Standard reproduces verbatim ISO 7800:2003 and implements it as the UK national standard. The UK participation in its preparation was entrusted by Technical
3、Committee ISE/NFE/4, Mechanical testing of metals, to Subcommittee ISE/NFE/4/2, Ductility testing, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement internation
4、al publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all
5、 the necessary provisions of a contract. Users are responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on
6、 the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii to iv, pages 1 to 7 and
7、 a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. Amendments issued since publication Amd. No. DateComments Licensed Copy: London South Bank University, London South Bank University, Thu Mar 01 07:01:29 GMT+00:00 2007, Uncontrolled Copy,
8、(c) BSI Reference number ISO 7800:2003(E) OSI 3002 INTERNATIONAL STANDARD ISO 7800 Second edition 2003-09-01 Metallic materials Wire Simple torsion test Matriaux mtalliques Fils Essai de torsion simple BS ISO 7800:2003 Licensed Copy: London South Bank University, London South Bank University, Thu Ma
9、r 01 07:01:29 GMT+00:00 2007, Uncontrolled Copy, (c) BSI IS:0087 O3002(E) DPlcsid Fremia ihTs PDF file mya ctnoian emdebt dedyfepcaes. In ccacnadrow eitA hebods licnesilop gnic,y tihs file mirp eb yatnde iv roweb detu slahl ton ide ebtlnu deess teh typfecaes wihce era hml era deddebicsnede ti dna on
10、stlalde t noeh comuptfrep reromign tide ehtin.g In wodlnidaot gnihs fil,e trapise atpecc tiereht nser ehnopsiiblity fo nto ifnriigngn Aebods licnesilop gnic.y ehT ISO tneClar Secrteirata caceptl on siibality in this .aera Ai ebods a tedarmfo kra Aebod SystemI snctaropro.de teDials fo teh sfotwcudorp
11、 erats sut deo crtaee tihs PDF file cna f ebi dnuon tlareneG eh Ifnler oatit evt oeh file; tP ehDc-Frtaeino marapterew stpo ereimizde fro irptni.gn Evyre cera neeb sah takne tsne oeru taht teh file is siutlbae fosu re yb ISO memdob rebeis. In tlnu ehikletneve y ttah lborp aem lertait gno it is f,dnu
12、o plsaee ifnrom ttneC ehlar Secterirata ta teh serddaig sleb nevwo. ISO 3002 All irthgs erse.devr lnUeto sswrehise specified, on trap fo this lbupictaion maeb y cudorperro de tuilizi den yna form ro na ybm ynae,s lecetrinoc ro mceinahcla, incliduntohp gcoiypodna gn micrfoilm, wittuoh repmissii now n
13、ritign from ietI rehSa Ot tsserdda eh ebolw or ISOs memreb i ydobn the cnuotfo yr ttseuqer ehe.r ISO cirypothg fofice saCe tsopale 65 eneG 1121-HC 02 av leT. 4 + 10 947 22 1 11 xaF0 947 22 14 + 9 74 E-mial coirypthgis.o gro We bwww.is.o gro ii ISO 3002 Allr ihgtsser edevr BS ISO 7800:2003 Licensed C
14、opy: London South Bank University, London South Bank University, Thu Mar 01 07:01:29 GMT+00:00 2007, Uncontrolled Copy, (c) BSI ISO 7800:2003(E) I SO 3002 All irhgts seredevr iii Contents Page Forewordiv 1 Scope1 2 Symbols and designations.1 3 Principle.1 4 Testing equipment2 5 Test piece.2 6 Testin
15、g conditions2 7 Procedure.3 8 Test report3 Annex A (informative) Recommended types of grip depending on the diameter, d, or characteristic dimension, D, of the wire.5 Annex B (informative) Recommended method of straightening curved wires sufficiently to place them in test grips 6 Annex C (informativ
16、e) Evaluation of fractures occurring during simple torsion test.7 3002:0087 OSI SBBS ISO 7800:2003 Licensed Copy: London South Bank University, London South Bank University, Thu Mar 01 07:01:29 GMT+00:00 2007, Uncontrolled Copy, (c) BSI ISO 7800:2003(E) iv I SO 3002 All irhgts seredevr Foreword ISO
17、(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 interested in a subject for which a technical comm
18、ittee 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 Commission (IEC) on all matters of electrote
19、chnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the memb
20、er bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. 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 for identifyi
21、ng any or all such patent rights. ISO 7800 was prepared by Technical Committee ISO/TC 164, Mechanical testing of metals, Subcommittee SC 2, Ductility testing. This second edition cancels and replaces the first edition (ISO 7800:1984), which has been technically revised. 3002:0087 OSI SBBS ISO 7800:2
22、003 Licensed Copy: London South Bank University, London South Bank University, Thu Mar 01 07:01:29 GMT+00:00 2007, Uncontrolled Copy, (c) BSI INTENRATIONAL TSANDADR IS:0087 O3002(E) I SO 3002 All irhgts seredevr 1 Metallic materials Wire Simple torsion test 1 Scope This International Standard specif
23、ies a method for determining the ability of metallic wire of diameter or characteristic dimension 0,1 mm to 10 mm inclusive to undergo plastic deformation during simple torsion in one direction. 2 Symbols and designations The symbols and designations used in the simple torsion test of wires are show
24、n in Figure 1 and listed in Table 1. 3 Principle The test consists of twisting a test piece of wire around its own axis in one direction. Key 1 grip Figure 1 Table 1 Symbols and designations Symbol Designation Unit d Diameter of a round wire mm D Characteristic dimension for non-circular wires a mm
25、L Free length between grips mm Nt Number of turns a The characteristic dimension for non-circular wires is the maximum dimension of the cross section and is usually specified in the relevant standard. BS ISO 7800:2003 Licensed Copy: London South Bank University, London South Bank University, Thu Mar
26、 01 07:01:29 GMT+00:00 2007, Uncontrolled Copy, (c) BSI IS:0087 O3002(E) 2 I SO 3002 All irhgts seredevr 4 Testing equipment 4.1 Grips, having a minimum hardness of 55 HRC, and parallel faces. The recommended types of grips are given in Annex A. 4.2 Testing machine, constructed so that a change of l
27、ength between the grips, caused by contraction of the test piece during testing, is not prevented and that an appropriate tensile stress (see 7.1) may be applied to the test piece. The grips shall be placed in the testing machine in such a way that during testing they remain on the same axis and do
28、not apply any bending force to the test piece. One of the grips shall be capable of being rotated around the axis of the test piece while the other shall not be subject to any angular deflection, except for such deflection as may be necessary to measure the torque. The distance between the grips sha
29、ll be capable of adjustment for different test piece lengths. 5 Test piece 5.1 The length of wire to be used as the test piece shall be as straight as possible. 5.2 If straightening is necessary, it shall be done by a suitable method. A recommended method is given in Annex B. During straightening, t
30、he surface of the wire shall not be damaged and the test piece shall not be subjected to any twisting. Wire with localized sharp curvature shall not be tested. Unless otherwise specified, the nominal free length between the grips shall be as given in Table 2. Table 2 Dependence of free length betwee
31、n the grips on nominal diameter or characteristic dimension of the wire Nominal diameter, d, or characteristic dimension, D mm Free length between grips (nominal) a 0,3 u d (D) 3 V-grooved BS ISO 7800:2003 Licensed Copy: London South Bank University, London South Bank University, Thu Mar 01 07:01:29
32、 GMT+00:00 2007, Uncontrolled Copy, (c) BSI IS:0087 O3002(E) 6 I SO 3002 All irhgts seredevr Annex B (informative) Recommended method of straightening curved wires sufficiently to place them in test grips The following is a method of straightening wires sufficiently to be able to place them in test
33、grips of a torsion wire tester. This procedure is suggested for thick, high strength wire, which may present a safety hazard to the test operator if an attempt is made to place the wire in the test grips without first securing the wire. Equipment includes: a bench mounted vice, two adjustable vice g
34、rips and a piece of wood approximately 45 mm wide by 20 mm thick by a length slightly less than the free length between the grips given in Table 2, column 2 of this International Standard. The 20 mm dimension may be tapered from the centre to each end so that the ends of the wood are approximately 1
35、5 mm thick. Place the wood (45 mm dimension) securely between the jaws of the vice and clamp. Wrap a cushioning agent (such as masking tape) around the jaw of each vice grip that will be in contact with the wire when it is clamped to the board. The masking tape will protect the wire from being damag
36、ed (nicked). Place the wire (curvature down) on top of the board so that an equal length of the wire will extend beyond each end of the board. Adjust the vice grip and place the cushioned jaw on top of the wire near one end of the board. Grasp the other end of the wire and bend it down on the board.
37、 Clamp the wire in place with the other adjusted vice grip ensuring that the cushioned jaw is in contact with the wire. Insert the ends of the wire in the grips, apply a tensile stress not exceeding 2 % of the nominal tensile strength of the wire, release the vice grips and remove the board. Duplica
38、te set-ups may be made so that the next wire to be tested will be available when needed. BS ISO 7800:2003 Licensed Copy: London South Bank University, London South Bank University, Thu Mar 01 07:01:29 GMT+00:00 2007, Uncontrolled Copy, (c) BSI IS:0087 O3002(E) I SO 3002 All irhgts seredevr 7 Annex C
39、 (informative) Evaluation of fractures occurring during simple torsion test Type No. Aspect Description and characteristics Fracture plane Type of fracture Product Normal torsion fracture 1 a b Smooth: fracture plane perpendicular to wire axis (or slightly oblique). No cracks in fracture plane. Brit
40、tle: fracture plane at an angle of 45 to wire axis. No cracks in fracture plane. Fracture with local cracks Regular fracture (material defects) 2 a b c Smooth: fracture plane perpendicular to wire axis and partially cracked. Stepped: a part of the fracture plane is still smooth: partially cracked. I
41、rregular fracture plane: no cracks in fracture plane. Fracture with spiral cracks over the whole length (or large part of it) Crack formation already occurs after a low number (3 to 5) of torsions and is best visible at that moment 3 a b c Smooth: fracture plane perpendicular to wire axis and partia
42、lly or entirely cracked. Stepped: a part of the fracture plane is still smooth and partially or entirely cracked. Brittle: fracture plane at an angle of 45 and partially or entirely cracked or irregular fracture plane and partially or entirely cracked BS ISO 7800:2003 Licensed Copy: London South Ban
43、k University, London South Bank University, Thu Mar 01 07:01:29 GMT+00:00 2007, Uncontrolled Copy, (c) BSI BS ISO 7800:2003 BSI 389 Chiswick High Road London W4 4AL BSI British Standards Institution BSI is the independent national body responsible for preparing British Standards. It presents the UK
44、view on standards in Europe and at the international level. It is incorporated by Royal Charter. Revisions British Standards are updated by amendment or revision. Users of British Standards should make sure that they possess the latest amendments or editions. It is the constant aim of BSI to improve
45、 the quality of our products and services. We would be grateful if anyone finding an inaccuracy or ambiguity while using this British Standard would inform the Secretary of the technical committee responsible, the identity of which can be found on the inside front cover. Tel: +44 (0)20 8996 9000. Fa
46、x: +44 (0)20 8996 7400. BSI offers members an individual updating service called PLUS which ensures that subscribers automatically receive the latest editions of standards. Buying standards Orders for all BSI, international and foreign standards publications should be addressed to Customer Services.
47、 Tel: +44 (0)20 8996 9001. Fax: +44 (0)20 8996 7001. Email: ordersbsi-. Standards are also available from the BSI website at http:/www.bsi-. In response to orders for international standards, it is BSI policy to supply the BSI implementation of those that have been published as British Standards, un
48、less otherwise requested. Information on standards BSI provides a wide range of information on national, European and international standards through its Library and its Technical Help to Exporters Service. Various BSI electronic information services are also available which give details on all its
49、products and services. Contact the Information Centre. Tel: +44 (0)20 8996 7111. Fax: +44 (0)20 8996 7048. Email: infobsi-. Subscribing members of BSI are kept up to date with standards developments and receive substantial discounts on the purchase price of standards. For details of these and other benefits contact Membership Administration. Tel: +44 (0)20 8996 7002. Fax: +44 (0)20 8996 7001. Email: membershipbsi-glo