1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58environmental stress cracking (ESC) Part 2: Constant tensile load methodThe European Standard EN IS
2、O 22088-2:2006 has the status of a British StandardICS 83.080.01Plastics Determination of resistance to BRITISH STANDARDBS EN ISO 22088-2:2006BS EN ISO 22088-2:2006This British Standard was published under the authority of the Standards Policy and Strategy Committee on 29 September 2006 BSI 2006ISBN
3、 0 580 48767 9Amendments issued since publicationAmd. No. Date CommentsThis publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.National
4、forewordThis British Standard was published by BSI. It is the UK implementation of EN ISO 22088-2:2006. It supersedes BS EN ISO 6252:1998 which is withdrawn.The UK participation in its preparation was entrusted to Technical Committee PRI/21, Testing of plastics.A list of organizations represented on
5、 PRI/21 can be obtained on request to its secretary.EUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMEN ISO 22088-2August 2006ICS 83.080.01 Supersedes EN ISO 6252:1997 English VersionPlastics - Determination of resistance to environmental stresscracking (ESC) - Part 2: Constant tensile load method (IS
6、O22088-2:2006)Plastiques - Dtermination de la fissuration sous contraintedans un environnement donn (ESC) - Partie 2: Mthodesous contrainte de traction constante (ISO 22088-2:2006)Kunststoffe - Bestimmung der Bestndigkeit gegenumgebungsbedingte Spannungsrissbildung (ESC) - Teil 2:Zeitstandzugversuch
7、 (ISO 22088-2:2006)This European Standard was approved by CEN on 21 July 2006.CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this EuropeanStandard the status of a national standard without any alteration. Up-to-date lists and bibli
8、ographical references concerning such nationalstandards may be obtained on application to the Central Secretariat or to any CEN member.This European Standard exists in three official versions (English, French, German). A version in any other language made by translationunder the responsibility of a
9、CEN member into its own language and notified to the Central Secretariat has the same status as the officialversions.CEN members are the national standards bodies of Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
10、 Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.EUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGManagement Centre: rue de Stassart, 36 B-1050 Brussels 200
11、6 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.Ref. No. EN ISO 22088-2:2006: EForeword This document (EN ISO 22088-2:2006) has been prepared by Technical Committee ISO/TC 61 “Plastics“ in collaboration with Technical Committee CEN/TC 249 “Pla
12、stics“, the secretariat of which is held by IBN. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by February 2007, and conflicting national standards shall be withdrawn at the latest by February 2007
13、. This document supersedes EN ISO 6252:1997. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece,
14、 Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom. Endorsement notice The text of ISO 22088-2:2006 has been approved by CEN as EN ISO 22088-2:2006 without any modi
15、fications. EN ISO 22088-2:2006Reference numberISO 22088-2:2006(E)INTERNATIONAL STANDARD ISO22088-2First edition2006-08-15Plastics Determination of resistance to environmental stress cracking (ESC) Part 2: Constant tensile load method Plastiques Dtermination de la fissuration sous contrainte dans un
16、environnement donn (ESC) Partie 2: Mthode sous contrainte de traction constante EN ISO 22088-2:2006ii iiiContents Page Foreword iv 1 Scope . 1 2 Normative references . 1 3 Principle. 2 4 Apparatus 2 5 Conditioning and test conditions 3 5.1 Conditioning 3 5.2 Test temperature. 3 5.3 Test medium 3 6 T
17、est stress . 4 6.1 Maximum permissible stress. 4 6.2 Method A 4 6.3 Method B 4 6.4 Method C 4 7 Test specimens . 4 7.1 General. 4 7.2 Shape and dimensions. 4 7.3 Number 5 7.4 Preparation 5 8 Procedure 6 9 Expression of results . 7 9.1 Method A 7 9.2 Method B 7 9.3 Method C 7 10 Precision 7 11 Test r
18、eport . 8 Annex A (informative) Examples of stresses to be applied. 9 Bibliography . 10 EN ISO 22088-2:2006iv 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
19、 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. International organizations, governmental and non-governmental, in liaison with ISO, also take part
20、 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 rules given in the ISO/IEC Directives, Part 2. The main task of technical committees is to pr
21、epare 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 at least 75 % of the member bodies casting a vote. Attention is drawn to the possibility that
22、 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 22088-2 was prepared by Technical Committee ISO/TC 61, Plastics, Subcommittee SC 6, Ageing, chemical and environmental resistance. It cance
23、ls and replaces ISO 6252:1992, which has been technically revised. ISO 22088 consists of the following parts, under the general title Plastics Determination of resistance to environmental stress cracking (ESC): Part 1: General guidance Part 2: Constant tensile load method (replacement of ISO 6252:19
24、92) Part 3: Bent strip method (replacement of ISO 4599:1986) Part 4: Ball or pin impression method (replacement of ISO 4600:1992) Part 5: Constant tensile deformation method (new test method) Part 6: Slow strain rate method (new test method) EN ISO 22088-2:20061Plastics Determination of resistance t
25、o environmental stress cracking (ESC) Part 2: Constant tensile load method 1 Scope This part of ISO 22088 specifies methods for the determination of environmental stress cracking (ESC) of thermoplastics when they are subjected to a constant tensile load in the presence of chemical agents. It is appl
26、icable to test specimens prepared by moulding and/or machining and can be used both for the assessment of ESC of plastic materials exposed to different environments, and for the determination of ESC of different plastic materials exposed to a specific environment. This is essentially a ranking test
27、and is not intended to provide data to be used for design or performance prediction. NOTE Methods for the determination of environmental stress cracking by means of a constant-strain test are specified in ISO 22088-3, ISO 22088-4 and ISO 22088-5. 2 Normative references The following referenced docum
28、ents are indispensable for the application 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 293, Plastics Compression moulding of test specimens of thermoplastic mater
29、ials ISO 294-1, Plastics Injection moulding of test specimens of thermoplastic materials Part 1: General principles, and moulding of multipurpose and bar test specimens ISO 527-2:1993, Plastics Determination of tensile properties Part 2: Test conditions for moulding and extrusion plastics ISO 2818,
30、Plastics Preparation of test specimens by machining ISO 3167, Plastics Multipurpose test specimens ISO 22088-1:2006, Plastics Determination of resistance to environmental stress cracking (ESC) Part 1: General guidance EN ISO 22088-2:20062 3 Principle A test specimen is subjected to a constant tensil
31、e load, corresponding to a stress lower than that at yield, while immersed in a specified environment at the temperature selected for testing. The time and/or stress at which the specimen breaks is recorded. The environmental stress cracking of the test specimens is determined by one of the followin
32、g methods (A, B or C), depending upon the time to rupture: Method A: Determination of the tensile stress leading to rupture at 100 h. This stress is obtained by interpolation of the graph of time to rupture versus applied tensile stress. Method B: Determination of the time to rupture under a specifi
33、ed tensile stress. This method is used when the time to rupture exceeds 100 h. Method C: Determination of the time to rupture for a series of applied stresses. The graph of time to rupture versus applied stress is then examined to determine if the rupture time for some agreed-upon applied stress is
34、satisfactory. 4 Apparatus 4.1 Test device, allowing test specimens to be simultaneously subjected to a tensile load and exposed to a chemical environment. If the chemical is a liquid at the test temperature, the test specimen shall be completely immersed. If it is highly viscous at the test temperat
35、ure, the specimen may be covered with a coating of the agent at least 2 mm thick (see Clause 5). Parts of the device that come into contact with the test medium shall be made of an inert material. The constant tensile load may be applied with weights (Figure 1 is a schematic diagram of a suitable ap
36、paratus). The force shall be accurate to 1 % of the specified force. It is important to ensure that there is no unintended contact between moving parts, and that all moving parts of the apparatus are properly maintained and lubricated as appropriate. If the test device has several test stations, mea
37、ns shall be provided to prevent the vibration occurring through failure at one station from being transmitted to the whole system. Unless otherwise specified, forces shall be applied parallel to the longitudinal axis. NOTE Bending or twisting forces will produce different stresses and may affect the
38、 results and increase test variability. 4.2 Temperature-controlled bath or room, allowing the containers to be maintained at (23 2) C or at a higher test temperature up to (105 2) C (see 5.2). 4.3 Automatic timer, as shown schematically in Figure 1, to measure the time to rupture of each specimen to
39、 within 1 % of the elapsed time. 4.4 Equipment for the preparation of test specimens by moulding (see ISO 293 and ISO 294-1), machining (see ISO 2818) or die cutting. EN ISO 22088-2:20063Key 1 balance 2 frictionless bearing, or knife edge 3 wire attachment point 4 wire 5 circulation of temperature-c
40、ontrolled liquid 6 clamps 7 test specimen 8 chemical environment 9 weights 10 switch controlling timer 11 timer Figure 1 One type of apparatus for measuring fracture under constant load 5 Conditioning and test conditions 5.1 Conditioning Unless otherwise agreed between the interested parties, the te
41、st specimens shall be conditioned before testing for at least 24 h at (23 2) C and (50 10) % relative humidity. 5.2 Test temperature The preferred test temperatures are (23 2) C and (55 2) C. If required, other temperatures may be used, preferably selected from the following: (40 2) C, (70 2) C, (85
42、 2) C, (100 2) C or as agreed upon by the interested parties. 5.3 Test medium See ISO 22088-1:2006, 7.3. EN ISO 22088-2:20064 6 Test stress 6.1 Maximum permissible stress The stress applied to the test specimen during the test shall be less than the tensile stress at yield of the material at the tem
43、perature of the test. NOTE As a general guide, the stress that produces an elongation of 2 % after 1 h can be taken as the maximum permissible stress. This stress can be determined by preliminary tests using several different stresses. 6.2 Method A Conduct tests at a series of applied stress levels
44、to determine the applied stress that will cause failure in 100 h. Test a minimum of five specimens at each applied stress. The applied stress needed to produce failure in 100 h is calculated as described in 9.1. 6.3 Method B Determine the time to rupture under a single stress agreed between the inte
45、rested parties, but not higher than the maximum permissible stress defined in 6.1. 6.4 Method C Determine the times to rupture for agreed-upon applied stresses. The series of stresses shall be chosen in accordance with 8.7. Test a minimum of two specimens at each applied stress. The result is report
46、ed as the time to rupture for a particular applied stress. Method A is a subset of method C. 7 Test specimens 7.1 General When moulding test specimens, or when machining and polishing test specimens cut from large sheets or products, it is important to minimize any residual stress. Use the mildest c
47、onditions possible during specimen preparation. Annealing specimens prior to testing is recommended. Report the exact conditions used for specimen preparation and the conditions used for any annealing of specimens prior to testing. 7.2 Shape and dimensions Wherever possible, use the type 1BA small t
48、est specimen specified in Annex A of ISO 527-2:1993, as shown in Figure 2. The preferred thickness is (2 0,2) mm, but when the test specimens are prepared from finished products the thickness may be that of the product. Alternatively, a type 1BA specimen 3 mm to 4 mm thick may be used. EN ISO 22088-
49、2:20065Key l3overall length: 75 mm b2width at ends: (10 0,5) mm l1length of narrow, parallel-sided portion: (30 0,5) mm b1width of narrow, parallel-sided portion: (5 0,5) mm r radius, minimum: 30 mm h thickness: preferably (2 0,2) mm l0distance between gauge marks: 25 mm l2initial distance between grips: 57 mm Figure 2 ISO 527-2 type 1BA specimen (type 1B scaled down 2:1) 7.3 Number At least five specimens shall be tested at each tensile
