1、Rubber, vulcanized or thermoplastic Determination of flex cracking and crack growth (De Mattia)BS ISO 132:2017BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06 ISO 2017Rubber, vulcanized or thermoplastic Determination of flex cracking and crack growth (De Mattia)Caout
2、chouc vulcanis ou thermoplastique Dtermination de la rsistance au dveloppement dune craquelure (De Mattia)INTERNATIONAL STANDARDISO132Sixth edition2017-07Reference numberISO 132:2017(E)National forewordThis British Standard is the UK implementation of ISO 132:2017. It supersedes BS ISO 132:2011, whi
3、ch is withdrawn.The UK participation in its preparation was entrusted to Technical Committee PRI/22, Testing and analysis of rubber.A list of organizations represented on this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 provisi
4、ons of a contract. Users are responsible for its correct application. The British Standards Institution 2017 Published by BSI Standards Limited 2017ISBN 978 0 580 97195 2ICS 83.060Compliance with a British Standard cannot confer immunity from legal obligations. This British Standard was published un
5、der the authority of the Standards Policy and Strategy Committee on 31 August 2017.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS ISO 132:2017 ISO 2017Rubber, vulcanized or thermoplastic Determination of flex cracking and crack growth (De Mattia)Caoutchouc vulcani
6、s ou thermoplastique Dtermination de la rsistance au dveloppement dune craquelure (De Mattia)INTERNATIONAL STANDARDISO132Sixth edition2017-07Reference numberISO 132:2017(E)BS ISO 132:2017ISO 132:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll
7、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 photocopying, or posting on the internet or an intranet, without prior written permission. Permission can be requested fro
8、m either ISO at the address below or ISOs member body in the country of the requester.ISO copyright officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 132:2017ISO 132:2017(E)ii ISO 2017 All rights reservedCOP
9、YRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll 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 photocopying, or posting on the internet or an intranet, w
10、ithout 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 officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.org
11、ISO 132:2017(E)Foreword ivIntroduction v1 Scope . 12 Normative references 13 Terms and definitions . 14 Apparatus . 15 Calibration 36 Test pieces . 36.1 Shape, dimensions and preparation . 36.2 Preparation of test pieces for crack growth measurement 36.3 Time interval between vulcanization and testi
12、ng 56.4 Conditioning 66.5 Number of test pieces . 67 Test conditions . 67.1 Temperature 67.2 Humidity . 68 Procedure. 68.1 General . 68.2 Determination of flex cracking 68.3 Determination of crack growth . 79 Expression of results 79.1 Determination of flex cracking 79.2 Determination of crack growt
13、h . 810 Precision . 811 Test report . 8Annex A (normative) Calibration schedule 10Annex B (informative) Precision 12Bibliography .15 ISO 2017 All rights reserved iiiContents PageBS ISO 132:2017ISO 132:2017(E)ForewordISO (the International Organization for Standardization) is a worldwide federation o
14、f 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 committee has been established has the right to be represented on that committee. In
15、ternational 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 electrotechnical standardization.The procedures used to develop this document and those i
16、ntended for its further maintenance are described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the different 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
17、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 not be held responsible for identifying any or all such patent rights. Details of any patent rights identified during the development of the docu
18、ment 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 information given for the convenience of users and does not constitute an endorsement.For an explanation on the voluntary nature of standards,
19、the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html.This document was prepar
20、ed by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 2, Testing and analysis.This sixth edition cancels and replaces the fifth edition (ISO 132:2011), of which it constitutes a minor revision to update normative references in Clause 2 and improve the title and the key for
21、 Figure 1.iv ISO 2017 All rights reservedBS ISO 132:2017ISO 132:2017(E)ForewordISO (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 techni
22、cal 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 liaison with ISO, also take part in the work. ISO collaborates closely w
23、ith the International 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
24、 for the different 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
25、rights. ISO shall not 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
26、in this document is information given for the convenience of users and does not constitute an endorsement.For an explanation on the voluntary nature of standards, the meaning of ISO specific terms and expressions related to conformity assessment, as well as information about ISOs adherence to the Wo
27、rld Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following URL: www .iso .org/ iso/ foreword .html.This document was prepared by Technical Committee ISO/TC 45, Rubber and rubber products, Subcommittee SC 2, Testing and analysis.This sixth edition cancels and r
28、eplaces the fifth edition (ISO 132:2011), of which it constitutes a minor revision to update normative references in Clause 2 and improve the title and the key for Figure 1.iv ISO 2017 All rights reserved ISO 132:2017(E)IntroductionRepeated bending or flexing of a rubber causes cracks to develop in
29、that part of the surface where tension stress is set up during flexing or, if this part of the surface contains a crack, causes this crack to extend in a direction perpendicular to the stress. Certain soft vulcanizates, for instance those prepared from styrene-butadiene rubber, show marked resistanc
30、e to crack initiation, but it is possible for these vulcanizates to have a low resistance to growth (propagation) of cracks. It is important, therefore, to measure both the resistance to crack initiation by flexing and the resistance to crack propagation.The method is suitable for rubbers that have
31、reasonably stable stress-strain properties, at least after a period of cycling, and do not show undue stress softening or set, or highly viscous behaviour. The results obtained for some thermoplastic rubbers should be treated with caution if the elongation at yield is below, or close to, the maximum
32、 strain imposed during the test. ISO 2017 All rights reserved vBS ISO 132:2017BS ISO 132:2017Rubber, vulcanized or thermoplastic Determination of flex cracking and crack growth (De Mattia)WARNING 1 Persons using this document should be familiar with normal laboratory practice. This document does not
33、 purport to address all of the safety problems, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions.WARNING 2 Certain procedures specified in this document might in
34、volve the use or generation of substances, or the generation of waste, that could constitute a local environmental hazard. Reference should be made to appropriate documentation on safe handling and disposal after use.1 ScopeThis document specifies a method of test intended for use in comparing the r
35、esistance of vulcanized or thermoplastic rubbers to the formation and growth of cracks, when subjected to repeated flexing on the De Mattia type machine. For determination of crack growth, an artificial cut is made in the test piece to initiate cut growth.2 Normative referencesThe following document
36、s are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 18899:2013, Rubb
37、er Guide to the calibration of test equipmentISO 23529, Rubber General procedures for preparing and conditioning test pieces for physical test methods3 Terms and definitionsNo terms and definitions are listed in this document.ISO and IEC maintain terminological databases for use in standardization a
38、t the following addresses: ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp IEC Electropedia: available at h t t p :/ www .electropedia .org/ 4 Apparatus4.1 De Mattia type machine, the essential features of which are as follows.The machine has stationary parts, provided with
39、grips for holding one end of each of the test pieces in a fixed position, and similar but reciprocating parts for holding the other end of each of the test pieces. The travel is 57005+ ,mm and is such that the maximum distance between each set of opposing grips is 7501+mm (see Figure 1).The reciproc
40、ating parts are so arranged that their motion is straight and in the direction of, and in the same plane as, the common centreline of each opposing pair of grips. The planes of the gripping surfaces of each opposing pair of grips remain parallel throughout the motion.INTERNATIONAL STANDARD ISO 132:2
41、017(E) ISO 2017 All rights reserved 1BS ISO 132:2017ISO 132:2017(E)The eccentric which actuates the reciprocating parts is driven by a constant-speed motor to give 5,00 Hz 0,17 Hz, with sufficient power to flex at least six, and preferably 12, test pieces at one test. The grips hold the test pieces
42、firmly, without undue compression, and enable individual adjustment to be made to the test pieces to ensure accurate insertion.It is useful to arrange the test pieces in two equal groups, so that one group is being flexed while the other group is being straightened, thus reducing the vibration in th
43、e machine.For testing at elevated or subnormal temperatures, the machine can be enclosed in a chamber with temperature control near the centre of the test piece to 2 C, if necessary, by using an air circulator.4.2 Piercing tool and suitable jig, for piercing the test pieces (see 6.2).Dimensions in m
44、illimetresKey1 upper grip2 lower gripaTravel.Figure 1 De Mattia type machine, front view showing extended test piece, side view showing bent test piece and the grip travel2 ISO 2017 All rights reservedBS ISO 132:2017ISO 132:2017(E)The eccentric which actuates the reciprocating parts is driven by a c
45、onstant-speed motor to give 5,00 Hz 0,17 Hz, with sufficient power to flex at least six, and preferably 12, test pieces at one test. The grips hold the test pieces firmly, without undue compression, and enable individual adjustment to be made to the test pieces to ensure accurate insertion.It is use
46、ful to arrange the test pieces in two equal groups, so that one group is being flexed while the other group is being straightened, thus reducing the vibration in the machine.For testing at elevated or subnormal temperatures, the machine can be enclosed in a chamber with temperature control near the
47、centre of the test piece to 2 C, if necessary, by using an air circulator.4.2 Piercing tool and suitable jig, for piercing the test pieces (see 6.2).Dimensions in millimetresKey1 upper grip2 lower gripaTravel.Figure 1 De Mattia type machine, front view showing extended test piece, side view showing
48、bent test piece and the grip travel2 ISO 2017 All rights reserved ISO 132:2017(E)5 CalibrationThe requirements for calibration of the test apparatus are given in Annex A.6 Test pieces6.1 Shape, dimensions and preparationEach test piece shall be a strip with a moulded groove. The strips can be moulde
49、d individually in a multiple-cavity mould, as shown in Figure 2, or can be cut from a wide slab having a moulded groove.The groove in the test piece shall have a smooth surface and be free from irregularities from which cracks can start prematurely. The groove shall be moulded into the test piece or slab by a half-round ridge in the centre of the cavity.The half-round ridge shall have a radius of 2,38 mm 0,03 mm. The moulded groove shall be perpendicular to the direction of mill grain.Results can
