1、BSI Standards PublicationBS EN ISO 178:2010+A1:2013Plastics Determination of flexural propertiesBS EN ISO 178:2010+A1:2013National forewordThis British Standard is the UK implementation of EN ISO 178:2010+A1:2013. It is identical to ISO 178:2010, incorporating amendment 1:2013. It supersedes BS EN I
2、SO 178:2010, which is withdrawn.The start and finish of text introduced or altered by amendment is indicated in the text by tags. Tags indicating changes to ISO text carry the number of the ISO amendment. For example, text altered by ISO amendment 1 is indicated by !“.The UK participation in its pre
3、paration was entrusted to Technical Committee PRI/21, Testing of plastics.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 a
4、pplication. The British Standards Institution 2013. Published by BSI Standards Limited 2013ISBN 978 0 580 77078 4ICS 83.080.01Compliance 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 31 January 2011.Amendments/corrigenda issued since publicationDate Text affected31 July 2013 Implementation of ISO amendment 1:2013 with CEN endorsement A1:2013BRITISH STANDARDEUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 178 ICS 83.080.01 English Version Plastics - Determina
6、tion of flexural properties (ISO 178:2010) Plastiques - Dtermination des proprits en flexion (ISO 178:2010) Kunststoffe - Bestimmung der Biegeeigenschaften (ISO 178:2010) This European Standard was approved by CEN on 14 December 2010. CEN members are bound to comply with the CEN/CENELEC Internal Reg
7、ulations which stipulate 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 mem
8、ber. This European 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.
9、CEN members are the 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
10、, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR STANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: Avenue Marnix 17, B-1000 Brussels 2010 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN natio
11、nal Members. Ref. No. EN ISO 178:2010: E:2010+A1March 20133 Foreword This document (EN ISO 178:2010) has been prepared by Technical Committee ISO/TC 61 “Plastics” in collaboration with Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by NBN. This European Standard shall be
12、given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by June 2011, and conflicting national standards shall be withdrawn at the latest by June 2011. Attention is drawn to the possibility that some of the elements of this document may be
13、 the subject of patent rights. CEN and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 178:2003. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to imp
14、lement this European Standard: 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, S
15、witzerland and the United Kingdom. Endorsement notice The text of ISO 178:2010 has been approved by CEN as a EN ISO 178:2010 without any modification. This document (EN ISO 178:2010/A1:2013) has been prepared by Technical Committee ISO/TC 61 “Plastics“ in collaboration with Technical Committee CEN/T
16、C 249 “Plastics” the secretariat of which is held by NBN. This Amendment to the European Standard EN ISO 178:2010 shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by September 2013, and conflicting national standards shall
17、be withdrawn at the latest by September 2013. 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 identifying any or all such patent rights. According to the CEN-CENELEC Internal Re
18、gulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland,
19、 Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 178:2010/Amd 1:2013 has been approved by CEN as EN ISO 178:2010/A1:2013 without any modifica
20、tion. Foreword to amendment A1BS EN ISO 178:2010+A1:2013 ISO 178:2010+A1:2013 (E)EN ISO 2013 All rights reservediiiiiContents Page Foreword iv 1 Scope1 2 Normative references2 3 Terms and definitions .2 4 Principle .5 5 Test machine5 5.1 General .5 5.2 Test speed5 5.3 Supports and loading edge 6 5.4
21、 Force- and deflection-measuring systems .6 5.5 Equipment for measuring the width and thickness of the test specimens.7 6 Test specimens8 6.1 Shape and dimensions .8 6.2 Anisotropic materials9 6.3 Preparation of test specimens .9 6.4 Specimen inspection.10 6.5 Number of test specimens10 7 Atmosphere
22、 for conditioning and testing.10 8 Procedure.10 9 Calculation and expression of results 13 9.1 Flexural stress .13 9.2 Flexural strain 13 9.3 Flexural modulus.14 9.4 Statistical parameters .14 9.5 Significant figures .14 10 Precision 15 11 Test report15 Annex A (informative) Precision statement16 An
23、nex B (informative) Influence of changes in test speed on the measured values of flexural properties .18 Bibliography19 BS EN ISO 178:2010+A1:2013 ISO 178:2010+A1:2013 (E) ISO 2013 All rights reservediv Foreword ISO (the International Organization for Standardization) is a worldwide federation of na
24、tional 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. Intern
25、ational 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. International Standards are drafted in accordance with the
26、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 member bodies for voting. Publication as an International Standard requires approval by
27、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 identifying any or all such patent rights. ISO 178 was prepared by Technical Committee ISO/TC
28、 61, Plastics, Subcommittee SC 2, Mechanical properties. This fifth edition cancels and replaces the fourth edition (ISO 178:2001), which has been technically revised to harmonize it with ISO 527-22with respect to the test speeds used for the determination of the flexural modulus and for the determi
29、nation of other flexural properties. This has been done by specifying two methods, method A and method B. Method A is identical to the method specified in previous editions of ISO 178, i.e. it uses the same strain rate throughout the test, whereas method B uses two different strain rates (see 1.8 fo
30、r details). It also incorporates the Amendment ISO 178:2001/Amd.1:2004. !The fifth edition specifies measuring tips with an end radius of 50 mm. While this is useful to avoid alignment errors when dimensions on perfectly flat specimens are measured, it has disadvantages with injection-moulded specim
31、ens, which constitute the majority of specimens tested according to ISO 178. Injection-moulded specimens are never perfectly rectangular and, especially if made of semi-crystalline materials, also exhibit sink marks. Measuring tips with rounded ends tend to determine the minimum thickness, leading t
32、o artificially high values of stress and flexural modulus. Furthermore, the specified tips with round ends are not readily available and in the same instant rendered commonly used flat-ended tips obsolete, causing disagreement in audit processes. This amendment rectifies this error and introduces a
33、specification for measuring the dimensions of the test specimens that allows different instruments to be used, provided they measure not the extreme (maximum or minimum) dimensions, but rather an average value.“BS EN ISO 178:2010+A1:2013 ISO 178:2010+A1:2013 (E) ISO 2013 All rights reservedINTERNATI
34、ONAL STANDARD 1Plastics Determination of flexural properties 1 Scope 1.1 This International Standard specifies a method for determining the flexural properties of rigid (see 3.12) and semi-rigid plastics under defined conditions. A standard test specimen is defined, but parameters are included for a
35、lternative specimen sizes for use where appropriate. A range of test speeds is included. 1.2 The method is used to investigate the flexural behaviour of the test specimens and to determine the flexural strength, flexural modulus and other aspects of the flexural stress/strain relationship under the
36、conditions defined. It applies to a freely supported beam, loaded at midspan (three-point loading test). 1.3 The method is suitable for use with the following range of materials: thermoplastic moulding, extrusion and casting materials, including filled and reinforced compounds in addition to unfille
37、d types; rigid thermoplastics sheets; thermosetting moulding materials, including filled and reinforced compounds; thermosetting sheets. In agreement with ISO 10350-15and ISO 10350-26, this International Standard applies to fibre-reinforced compounds with fibre lengths u 7,5 mm prior to processing.
38、For long-fibre-reinforced materials (laminates) with fibre lengths 7,5 mm, see ISO 141257. The method is not normally suitable for use with rigid cellular materials or sandwich structures containing cellular material. In such cases, ISO 1209-13and/or ISO 1209-24can be used. NOTE For certain types of
39、 textile-fibre-reinforced plastic, a four-point bending test is preferred. This is described in ISO 14125. 1.4 The method is performed using specimens which may be either moulded to the specified dimensions, machined from the central section of a standard multipurpose test specimen (see ISO 20753) o
40、r machined from finished or semi-finished products, such as mouldings, laminates, or extruded or cast sheet. 1.5 The method specifies the preferred dimensions for the test specimen. Tests which are carried out on specimens of different dimensions, or on specimens which are prepared under different c
41、onditions, can produce results which are not comparable. Other factors, such as the test speed and the conditioning of the specimens, can also influence the results. NOTE Especially for semi-crystalline polymers, the thickness of the oriented skin layer, which is dependent on the moulding conditions
42、, also affects the flexural properties. 1.6 The method is not suitable for the determination of design parameters but can be used in materials testing and as a quality control test. 1.7 For materials exhibiting non-linear stress/strain behaviour, the flexural properties are only nominal. The equatio
43、ns given have been derived assuming linear elastic behaviour and are valid for deflections of the specimen that are small compared to its thickness. With the preferred specimen (which measures 80 mm 10 mm 4 mm) at the conventional flexural strain of 3,5 % and a span-to-thickness ratio, L/h, of 16, t
44、he deflection is 1,5h. Flexural tests are more appropriate for stiff and brittle materials showing small deflections at break than for very soft and ductile ones. BS EN ISO 178:2010+A1:2013 ISO 178:2010+A1:2013 (E) ISO 2013 All rights reserved2 1.8 Contrary to the previous editions of this Internati
45、onal Standard, this edition specifies two methods, method A and method B. Method A is identical to the method in previous editions of this International Standard, i.e. it uses a strain rate of 1 %/min throughout the test. Method B uses two different strain rates: 1 %/min for the determination of the
46、 flexural modulus and 5 %/min or 50 %/min, depending on the ductility of the material, for the determination of the remainder of the flexural stress-strain curve. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, o
47、nly the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 291, Plastics Standard atmospheres for conditioning and testing ISO 293, Plastics Compression moulding of test specimens of thermoplastic materials ISO 294-1:1
48、996, Plastics Injection moulding of test specimens of thermoplastic materials Part 1: General principles, and moulding of multipurpose and bar test specimens ISO 295, Plastics Compression moulding of test specimens of thermosetting materials ISO 2602, Statistical interpretation of test results Estim
49、ation of the mean Confidence interval ISO 2818, Plastics Preparation of test specimens by machining ISO 7500-1, Metallic materials Verification of static uniaxial testing machines Part 1: Tension/compression testing machines Verification and calibration of the force-measuring system ISO 9513, Metallic materials Calibration of extensometers used in uniaxial testing ISO 10724-1, Plastics Injection moulding of test specimens of thermosetting powder moulding compounds (PMCs) Part 1: General principles, and moulding of
