1、October 2009DEUTSCHE NORM English price group 9No part of this standard may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS 83.080.01!$ZBC“1553132w
2、ww.din.deDDIN EN ISO 22088-6Plastics Determination of resistance to environmental stress cracking (ESC) Part 6: Slow strain rate method (ISO 22088-6:2006)English version of DIN EN ISO 22088-6:2009-10Kunststoffe Bestimmung der Bestndigkeit gegen umgebungsbedingte Spannungsrissbildung (ESC) Teil 6: Ve
3、rfahren mit langsamer Dehnrate (ISO 22088-6:2006)Englische Fassung DIN EN ISO 22088-6:2009-10www.beuth.deDocument comprises 15 pagesDIN EN ISO 22088-6:2009-10 2 National foreword This standard has been prepared by Technical Committee ISO/TC 61 “Plastics” (Secretariat: ANSI, USA) in collaboration wit
4、h Technical Committee CEN/TC 249 “Plastics” (Secretariat: NBN, Belgium). The responsible German body involved in its preparation was the Normenausschuss Kunststoffe (Plastics Standards Committee), Technical Committee NA 054-01-04 AA Verhalten gegen Umgebungseinflsse. The DIN Standard corresponding t
5、o the International Standard referred to in clause 2 of the EN ISO is as follows: ISO 527-2 DIN EN ISO 527-2 DIN EN 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: Constan
6、t tensile load method Part 3: Bent strip method Part 4: Ball or pin impression method Part 5: Constant tensile deformation method Part 6: Slow strain rate method Because this standard does not contain any specifications regarding specimens, the results of tests carried out in accordance with this st
7、andard may vary. The effective gauge length is a geometric parameter and does not take into consideration compliance from the specimen-grip contact. Where there is no premature failure, a departure of the stress-strain curve in the test medium from that in air can also be a result of softening of th
8、e specimen due to absorption of or a reaction with the medium. In this case, there is no susceptibility to environmental stress cracking. National Annex NA (informative) Bibliography DIN EN ISO 527-2, Plastics Determination of tensile properties Part 2: Test conditions for moulding and extrusion pla
9、stics EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN ISO 22088-6 June 2009 ICS 83.080.01 English Version Plastics - Determination of resistance to environmental stress cracking (ESC) - Part 6: Slow strain rate method (ISO 22088-6:2006) Plastiques - Dtermination de la fissuration sous contraint
10、e dans un environnement donn (ESC) - Partie 6: Mthode vitesse de dformation lente (ISO 22088-6:2006) Kunststoffe - Bestimmung der Bestndigkeit gegen umgebungsbedingte Spannungsrissbildung (ESC) - Teil 6: Verfahren mit langsamer Dehnrate (ISO 22088-6:2006) This European Standard was approved by CEN o
11、n 23 May 2009. CEN members are bound to comply with the CEN/CENELEC Internal Regulations 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 b
12、e obtained on application to the CEN Management Centre or to any CEN member. 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
13、Management Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland, France,Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands,
14、 Norway, Poland, Portugal, Romania, Slovakia, Slovenia, 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 2009 CEN All rights of exploitation in any
15、form and by any means reserved worldwide for CEN national Members. Ref. No. EN ISO 22088-6:2009: E2 Contents Page Foreword3 1 Scope 4 2 Normative references 4 3 Terms and definitions .4 4 Principle6 5 Apparatus .8 6 Conditioning and test conditions.9 6.1 Conditioning.9 6.2 Test temperature9 6.3 Test
16、 medium.9 7 Test specimens9 8 Procedure .9 9 Expression of results . 10 10 Test report . 11 Annex A (normative) Strain calculation from crosshead displacement. 12 Bibliography. 13 DIN EN ISO 22088-6:2009-10 EN ISO 22088-6:2009 (E) Foreword The text of ISO 22088-6:2006 has been prepared by Technical
17、Committee ISO/TC 61 “Plastics” of the International Organization for Standardization (ISO) and has been taken over as EN ISO 22088-6:2009 by Technical Committee CEN/TC 249 “Plastics” the secretariat of which is held by NBN. This European Standard shall be given the status of a national standard, eit
18、her by publication of an identical text or by endorsement, at the latest by December 2009, and conflicting national standards shall be withdrawn at the latest by December 2009. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN a
19、nd/or CENELEC shall not be held responsible for identifying any or all such patent rights. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus, Czech Repub
20、lic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom. Endorsement notice The text of ISO 22088-6:2006 has
21、been approved by CEN as a EN ISO 22088-6:2009 without any modification. DIN EN ISO 22088-6:2009-10 EN ISO 22088-6:2009 (E) 34 1 Scope This part of ISO 22088 describes a procedure for assessing the environmental stress cracking (ESC) susceptibility of polymeric materials in chemical environments by s
22、lowly increasing the strain applied to a tensile specimen at a constant rate. It is applicable to test specimens prepared by moulding and/or machining and can be used to assess the relative ESC susceptibility of a material exposed to different environments or the relative ESC susceptibility of diffe
23、rent plastics exposed to a specific environment. This is essentially a ranking test and is not intended for the provision of design data. The principle advantage of the test compared with the test methods described in Parts 2 to 5 of ISO 22088 is the rapidity with which the ESC susceptibility of a p
24、articular polymer/environment combination can be assessed. 2 Normative references The following referenced documents 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 (in
25、cluding any amendments) applies. ISO 527-2, Plastics Determination of tensile properties Part 2: Test conditions for moulding and extrusion plastics ISO 22088-1, Plastics Determination of resistance to environmental stress cracking (ESC) Part 1: General guidance 3 Terms and definitions For the purpo
26、ses of this document, the terms and definitions given in ISO 22088-1 and the following apply. 3.1 crosshead displacement CHD distance the crosshead has moved from the start of the test 3.2 crosshead speed CHS distance travelled by the crosshead, CHD, divided by the time from the start of the test DI
27、N EN ISO 22088-6:2009-10 EN ISO 22088-6:2009 (E) 53.3 length of parallel-sided section of specimen l1length of the narrow parallel-sided section in the middle of the specimen (see Figure 1) 3.4 area of parallel-sided section A1cross-sectional area of the narrow parallel-sided section of the specimen
28、 (see Figure 1) 3.5 length of tapered region l2overall length of the tapered/non-parallel-sided region at one end of the specimen (see Figure 1) 3.6 length increment l2length of the sections into which the tapered/non-parallel-sided regions are divided in order to calculate the effective gauge lengt
29、h (see Figure 1) 3.7 area of incremental section in tapered section A2average cross-sectional area of one of the incremental sections into which the tapered/non-parallel-sided regions of the specimen are divided (see Figure 1) aNarrow parallel-sided section of the specimen, of length l1and cross-sec
30、tional area A1. bTapered/non-parallel-sided region of the specimen, of length l2. cIncremental sections (of no more than 1 mm in length) into which the tapered region is divided, of length l2and cross-sectional area A2. Figure 1 Schematic diagram of the specimen showing the relevant dimensions 3.8 e
31、ffective gauge length l0length of the specimen under strain, taking into account the contributions made by both the narrow parallel-sided section and the tapered sections at each end of the specimen NOTE The grips are assumed to extend up to the beginning of the tapered region of the specimen. If gr
32、ipped further back, allowance for the displacement in the wider parallel-sided section of the specimen will have to be made. The effective gauge length is given by: 201 122lllAA=+DIN EN ISO 22088-6:2009-10 EN ISO 22088-6:2009 (E) 6 3.9 stress force measured by the load cell divided by the initial cr
33、oss-sectional area, A13.10 strain distance, d, the crosshead has moved during the test, divided by the effective gauge length, l0(see Annex A) 3.11 strain rate l0is the gauge length as defined in Annex A. DIN EN ISO 22088-6:2009-10 EN ISO 22088-6:2009 (E) 10 8.3 Insert the specimen in the grips of t
34、he tensile-testing machine, ensuring that the specimen is axially aligned and completely enclosed within the environmental chamber. 8.4 Load the specimen rapidly ( 30 s) to a small load ( 100 N) just sufficient to take up any slack in the machine. 8.5 Fill the environmental chamber with the chemical
35、 under investigation to immerse the specimen. 8.6 Record the initial load and displacement, then switch on the data-logger. 8.7 Start the drive motor on the tensile-testing machine. 8.8 Allow the test to run until the specimen fractures or necks. 8.9 Inspect the specimen to ensure that it has not sl
36、ipped or broken in the grips. If slippage or fracture has occurred within the grips, record this and discard the results. 8.10 Unless otherwise agreed by the interested parties, conduct at least one repeat test. 8.11 To provide reference data, carry out the test in air in the same way as in the test
37、 medium. Unless otherwise agreed by the interested parties, the relative humidity of the air shall be (50 10) %. 9 Expression of results 9.1 The departure stress is determined by comparing the stress-strain curve in the environment with that in air. 9.2 Fit both stress-strain curves with third-order
38、 polynomials to the peak stress. If the correlation factor, R2, is 0,99, use a higher-order polynomial. This provides a convenient method to fit the data: = b + c2+ d39.3 Determine the derivative to obtain the tangent modulus of each polynomial at each stress: 2d23dbc d =+ + 9.4 Divide the derivativ
39、es (tangent moduli) obtained from the test conducted in the chemical environment by the derivatives obtained in air at each stress level. The departure stress is then defined as the stress at which this value equals to 0,75. chem airdd075, = 9.5 Record the value of the departure stress and all coeff
40、icients obtained for the polynomial fitted to the data. 9.6 The aggressivity of fluids or combinations of fluids on the polymer can be compared by normalizing the value of the departure stress relative to the maximum stress in air to obtain an ESC index: Departure stress in environmentESC indexMaxim
41、um stress in air= DIN EN ISO 22088-6:2009-10 EN ISO 22088-6:2009 (E) 1110 Test report The test report shall include the following information: a) a full description of the test material from which the specimens were taken, including composition, processing/service history and product type; b) the or
42、ientation, type and size of the test specimens and their surface preparation; c) the test medium used, including its chemical composition, temperature and pressure where appropriate; d) the test conditions, including the strain rate and the initial load and strain applied to the specimen; e) the ind
43、ividual test results and their arithmetic mean; f) the date of testing. DIN EN ISO 22088-6:2009-10 EN ISO 22088-6:2009 (E) 12 Annex A (normative) Strain calculation from crosshead displacement A.1 Assuming that the crosshead displacement is associated wholly with straining of the specimen, the strai
44、n is determined by estimating the extension of each element of material between the grips. The calculated strain in the gauge length is given by: 2112CHD 2llAA=+where CHD is the measured crosshead displacement; l1and A1are, respectively, the length and the cross-sectional area of the parallel-sided
45、section of the specimen; l2is an incremental length of the tapered/non-parallel-sided region of overall length l2 (one end only); A2is the cross-sectional area of an incremental section in the tapered region. Increments of l2shall not be greater than 1 mm in length. A schematic diagram of the specim
46、en is shown in Figure 1. A.2 The effective gauge length, l0, is taken as the denominator of the equation in Clause A.1 and is defined as: 201 122lllAA=+It should be noted that this calculation is required to define the strain rate. A.3 The grips are assumed to extend up to the beginning of the taper
47、ed region of the specimen. If the specimen is gripped further back, allowance for the displacement in the wider parallel-sided section of the specimen shall be made. DIN EN ISO 22088-6:2009-10 EN ISO 22088-6:2009 (E) 13Bibliography 1 TURNBULL, A., MAXWELL, A.S., PILLAI, S. Comparative assessment of
48、slow strain rate, 4-pt bend and constant load test methods for measuring environment stress cracking of polymers, Polymer Testing, 19 (2000), pp. 117-129 2 ARNOLD, J.C. The influence of liquid uptake on environmental stress cracking of glassy polymers, Mater. Sci. Eng., A197 (1995), p. 119 3 HOUGH,
49、M., WRIGHT, D. Two new test methods for assessing environmental stress cracking of amorphous thermoplastics, Polymer Testing, 15 (1996), p. 407 4 PILLAI, S., BULL, C., TURNBULL, A. Measurement of environment stress cracking of plastics, Euromat 97, Paper 2/59, Zwijndrecht: Netherlands Society for Materials Science, 1997 5 UGIANSKY, G.M., PAYER, J.H. (editors), Stress corrosion cracking The slow strain rate testing, ASTM STP 665, 1979 6 ISO 22088-2, Plastics Det
