1、Rubber, vulcanized or thermoplastic Determination of low-temperature brittlenessBS ISO 812:2017BSI Standards PublicationWB11885_BSI_StandardCovs_2013_AW.indd 1 15/05/2013 15:06 ISO 2017Rubber, vulcanized or thermoplastic Determination of low-temperature brittlenessCaoutchouc vulcanis ou thermoplasti
2、que Dtermination de la fragilit basse tempratureINTERNATIONAL STANDARDISO812Fourth edition2017-07Reference numberISO 812:2017(E)National forewordThis British Standard is the UK implementation of ISO 812:2017. It supersedes BS ISO 812:2011, which is withdrawn.The UK participation in its preparation w
3、as 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 provisions of a contract. Users are responsible for its correct
4、application. The British Standards Institution 2017 Published by BSI Standards Limited 2017ISBN 978 0 580 97184 6ICS 75.160.10Compliance with a British Standard cannot confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy
5、Committee on 30 September 2017.Amendments/corrigenda issued since publicationDate Text affectedBRITISH STANDARDBS ISO 812:2017 ISO 2017Rubber, vulcanized or thermoplastic Determination of low-temperature brittlenessCaoutchouc vulcanis ou thermoplastique Dtermination de la fragilit basse tempratureIN
6、TERNATIONAL STANDARDISO812Fourth edition2017-07Reference numberISO 812:2017(E)BS ISO 812:2017ISO 812:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Unless otherwise specified, no part of this publication may be reproduced or
7、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 from either ISO at the address below or ISOs member body in the country of the requester.ISO copy
8、right officeCh. de Blandonnet 8 CP 401CH-1214 Vernier, Geneva, SwitzerlandTel. +41 22 749 01 11Fax +41 22 749 09 47copyrightiso.orgwww.iso.orgBS ISO 812:2017ISO 812:2017(E)ii ISO 2017 All rights reservedCOPYRIGHT PROTECTED DOCUMENT ISO 2017, Published in SwitzerlandAll rights reserved. Unless otherw
9、ise 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 from either ISO at the address be
10、low 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.orgISO 812:2017(E)Foreword iv1 Scope . 12 Normative references 13 Terms and definitions . 14 Appa
11、ratus and materials 25 Calibration 46 Test pieces . 47 Time interval between manufacture and testing . 48 Procedure. 58.1 Procedure A (determination of brittleness temperature) . 58.2 Procedure B (determination of 50 % brittleness temperature) 58.3 Procedure C (testing at a specified temperature) .
12、69 Precision . 710 Test report . 7Annex A (informative) Speed calibration of a solenoid-actuated low-temperature impact tester . 8Annex B (normative) Calibration schedule 11Annex C (informative) Precision 13Bibliography .15 ISO 2017 All rights reserved iiiContents PageBS ISO 812:2017ISO 812:2017(E)F
13、orewordISO (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 tec
14、hnical 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 International Electrotechnical Commission (IEC) on all matters o
15、f 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 types of ISO documents should be noted. This document
16、 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 not be held responsible for identifying any or all suc
17、h 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 information given for the convenience of users and d
18、oes 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 World Trade Organization (WTO) principles in the Technical Barriers to Tra
19、de (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 fourth edition cancels and replaces the third edition (ISO 812:2011), of which it constitutes a min
20、or revision.The changes compared to the previous edition are as follows: the normative references in Clause 2 have been updated; the definition of “failure” has been added in 3.4; a note has been added in 4.2.iv ISO 2017 All rights reservedBS ISO 812:2017ISO 812:2017(E)ForewordISO (the International
21、 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 committee has been est
22、ablished 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 electrotechnical standardiz
23、ation.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 types of ISO documents should be noted. This document was drafted in accordance wi
24、th 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 not be held responsible for identifying any or all such patent rights. Details of a
25、ny 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 information given for the convenience of users and does not constitute an endorse
26、ment.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 World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT) see the following UR
27、L: 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 fourth edition cancels and replaces the third edition (ISO 812:2011), of which it constitutes a minor revision.The changes compa
28、red to the previous edition are as follows: the normative references in Clause 2 have been updated; the definition of “failure” has been added in 3.4; a note has been added in 4.2.iv ISO 2017 All rights reserved INTERNATIONAL STANDARD ISO 812:2017(E)Rubber, vulcanized or thermoplastic Determination
29、of low-temperature brittlenessWARNING 1 Persons using this document should be familiar with normal laboratory practice. This document does not 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 heal
30、th practices and to ensure compliance with any national regulatory conditions.WARNING 2 Certain procedures specified in this document might involve the use or generation of substances, or the generation of waste, that could constitute a local environmental hazard. Reference should be made to appropr
31、iate documentation on safe handling and disposal after use.1 ScopeThis document specifies a method for determining the lowest temperature at which rubber materials do not exhibit brittle failure or the temperature at which half of the test pieces used in a test fail when impacted under specified con
32、ditions.The temperatures thus determined do not necessarily relate to the lowest temperature at which the material can be used since the brittleness will be affected by the conditions of test and especially by the rate of impact. Data obtained by this method are, therefore, intended to be used to pr
33、edict the behaviour of rubbers at low temperatures only in applications in which the conditions of deformation are similar to those specified in the test.Three procedures are described: procedure A, in which the brittleness temperature is determined; procedure B, in which the brittleness temperature
34、 for 50 % failure is determined; procedure C, in which the test piece is impacted at a specified temperature.Procedure C is used in the classification of rubber materials and for specification purposes.NOTE A similar test for rubber-coated fabrics is described in ISO 4646.2 Normative referencesThe f
35、ollowing documents 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
36、 18899:2013, Rubber Guide to the calibration of test equipmentISO 23529, Rubber General procedures for preparing and conditioning test pieces for physical test methods3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply.ISO and IEC maintain terminologic
37、al databases for use in standardization at the following addresses: IEC Electropedia: available at h t t p :/ www .electropedia .org/ ISO Online browsing platform: available at h t t p :/ www .iso .org/ obp ISO 2017 All rights reserved 1BS ISO 812:2017ISO 812:2017(E)3.1brittleness temperaturelowest
38、temperature at which none of a set of test pieces fractures due to low-temperature embrittlement when tested under the specified conditions3.250 % brittleness temperaturetemperature at which 50 % of a set of test pieces fractures due to low-temperature embrittlement when tested under the specified c
39、onditions3.3testing speedrelative linear velocity at impact between the striking edge of the test apparatus and a clamped test piece3.4failureany crack, fissure or hole visible to the naked eye, or complete separation into two or more pieces4 Apparatus and materials4.1 Test piece clamp and striker,
40、meeting the requirements of 4.1.1 to 4.1.3.4.1.1 The test piece clamp shall be rigid and designed to hold the test piece(s) as cantilever beam(s). Each individual test piece shall be held firmly and securely in the clamp without distortion. A suitable example of a clamp is shown in Figure 1.Key1 tes
41、t piece2 body of clamp3 holding screw4 test piece holderFigure 1 Example of test piece clamp4.1.2 The striking edge shall move relative to the test piece(s) along a path normal to the upper surface of the test piece(s) at a linear testing speed of 2,0 m/s 0,2 m/s at impact. The speed shall be mainta
42、ined within this range for at least 6 mm of travel following the impact.In order to obtain a speed within the specified limits during and after impact, care shall be taken to ensure that the striking energy is sufficient. It has been found that a striking energy of at least 3,0 J per test piece is n
43、ecessary. It might, therefore, be necessary to limit the number of test pieces impacted at one time.2 ISO 2017 All rights reservedBS ISO 812:2017ISO 812:2017(E)3.1brittleness temperaturelowest temperature at which none of a set of test pieces fractures due to low-temperature embrittlement when teste
44、d under the specified conditions3.250 % brittleness temperaturetemperature at which 50 % of a set of test pieces fractures due to low-temperature embrittlement when tested under the specified conditions3.3testing speedrelative linear velocity at impact between the striking edge of the test apparatus
45、 and a clamped test piece3.4failureany crack, fissure or hole visible to the naked eye, or complete separation into two or more pieces4 Apparatus and materials4.1 Test piece clamp and striker, meeting the requirements of 4.1.1 to 4.1.3.4.1.1 The test piece clamp shall be rigid and designed to hold t
46、he test piece(s) as cantilever beam(s). Each individual test piece shall be held firmly and securely in the clamp without distortion. A suitable example of a clamp is shown in Figure 1.Key1 test piece2 body of clamp3 holding screw4 test piece holderFigure 1 Example of test piece clamp4.1.2 The strik
47、ing edge shall move relative to the test piece(s) along a path normal to the upper surface of the test piece(s) at a linear testing speed of 2,0 m/s 0,2 m/s at impact. The speed shall be maintained within this range for at least 6 mm of travel following the impact.In order to obtain a speed within t
48、he specified limits during and after impact, care shall be taken to ensure that the striking energy is sufficient. It has been found that a striking energy of at least 3,0 J per test piece is necessary. It might, therefore, be necessary to limit the number of test pieces impacted at one time.2 ISO 2
49、017 All rights reserved ISO 812:2017(E)4.1.3 The principal dimensions of the apparatus see Figures 2 a) and b) shall be as follows:a) the striking edge shall have a radius of 1,6 mm 0,1 mm;b) the clearance between the striker and the test piece clamp at impact shall be 6,4 mm 0,3 mm;c) the separation between the point of impact of the striking edge and the test piece clamp shall be 8 mm 0,3 mm;d) the clamping length of the test piece clamp shall be 6,8 mm 0,3 mm.NOTE Commercial appara
