1、November 2014Translation by DIN-Sprachendienst.English price group 11No part of this translation 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).IC
2、S 83.100!%=cH“2266437www.din.deDDIN EN ISO 844Rigid cellular plastics Determination of compression properties (ISO 844:2014);English version EN ISO 844:2014,English translation of DIN EN ISO 844:2014-11Harte Schaumstoffe Bestimmung der Druckeigenschaften (ISO 844:2014);Englische Fassung EN ISO 844:2
3、014,Englische bersetzung von DIN EN ISO 844:2014-11Plastiques alvolaires rigides Dtermination des caractristiques de compression (ISO 844:2014);Version anglaise EN ISO 844:2014,Traduction anglaise de DIN EN ISO 844:2014-11SupersedesDIN EN ISO 844:2009-10www.beuth.deIn case of doubt, the German-langu
4、age original shall be considered authoritative.Document comprises 15 pages10.14 DIN EN ISO 844:2014-11 2 A comma is used as the decimal marker. National foreword This document (EN ISO 844:2014) has been prepared by Technical Committee ISO/TC 61 “Plastics” (Secretariat: SAC, China) in collaboration w
5、ith Technical Committee ISO/TC 249 “Plastics” (Secretariat: NBN, Belgium). The responsible German body involved in its preparation was the DIN-Normenausschuss Materialprfung (DIN Standards Committee Materials Testing), Working Committee NA 062-04-37 AA Prfung weich-elastischer Schaumstoffe. The DIN
6、Standards corresponding to the International Standards referred to in this document are as follows: ISO 1923 DIN EN ISO 1923 ISO 5725 DIN ISO 5725 (withdrawn) Amendments This standard differs from DIN EN ISO 844:2009-10 as follows: a) an alternative method; Procedure B, and all relevant specificatio
7、ns have been added; b) the choice of the procedure for the determination of the compressive strength and corresponding relative deformation, the compressive stress at 10 % relative deformation and the compressive modulus of rigid cellular plastics has been given in detail; c) “square metres” has bee
8、n replaced by “square millimetres”; d) “kilopascal” has been replaced by “megapascal”; e) Figure 1 has been revised and Figure 2 has been supplemented. Previous editions DIN 53421: 1958x-01, 1971-05, 1984-06 DIN EN ISO 844: 2009-10 National Annex NA (informative) Bibliography DIN EN ISO 1923, Cellul
9、ar plastics and rubbers Determination of linear dimensions DIN ISO 5725, Precision of test methods Determination of repeatability and reproducibility for a standard test method by interlaboratory tests (withdrawn) EN ISO 844August 2014 ICS 83.100 Supersedes EN ISO 844:2009English Version Rigid cellu
10、lar plastics - Determination of compression properties (ISO 844:2014) Plastiques alvolaires rigides - Dtermination des caractristiques de compression (ISO 844:2014) Harte Schaumstoffe - Bestimmung der Druckeigenschaften (ISO 844:2014) This European Standard was approved by CEN on 7 July 2014. CEN me
11、mbers 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 be obtained on applica
12、tion to the CEN-CENELEC 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-CENELEC Manag
13、ement Centre has the same status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia
14、, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey andUnited Kingdom. CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels 2014 CEN All rights of exploitation in any form and by any means reserved worldwi
15、de for CEN national Members. Ref. No. EN ISO 844:2014 EEUROPEAN COMMITTEE FOR STANDARDIZATIONCOMIT EUROPEN DE NORMALISATIONEUROPISCHES KOMITEE FR NORMUNGEUROPEAN STANDARDNORME EUROPENNEEUROPISCHE NORMContents Page Foreword . 3 1 Scope . 4 2 Normative references. 4 3 Terms and definitions 4 4 Symbols
16、 and abbreviated terms . 5 5 Principle 5 6 Apparatus 5 6.1 Compression-testing machine 5 6.2 Devices for measuring displacement and force . 6 6.3 Instruments for measuring the dimensions of the test specimens 6 7 Test specimens 6 7.1 Dimensions . 6 7.2 Preparation . 7 7.3 Number 7 7.4 Conditioning .
17、 7 8 Procedure 7 9 Expression of results . 8 9.1 General 8 9.2 Compressive strength and corresponding relative deformation 9 9.3 Compressive stress at 10 % relative deformation 10 9.4 Compressive modulus of elasticity 10 10 Precision . 11 11 Test report . 11 Bibliography 13 2DIN EN ISO 844:2014-11 E
18、N ISO 844:2014 (E) ForewordThis document (EN ISO 844:2014) 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 given the status of a national standard, e
19、ither by publication of an identical text or by endorsement, at the latest by February 2015, and conflicting national standards shall be withdrawn at the latest by February 2015. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. CEN
20、 and/or CENELEC shall not be held responsible for identifying any or all such patent rights. This document supersedes EN ISO 844:2009. According to the CEN-CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Aus
21、tria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Swed
22、en, Switzerland, Turkey and the United Kingdom. Endorsement notice The text of ISO 844:2014 has been approved by CEN as EN ISO 844:2014 without any modification. 3DIN EN ISO 844:2014-11EN ISO 844:2014 (E)1 ScopeThis International Standard specifies a method of determining:a) the compressive strength
23、 and corresponding relative deformation,orb) the compressive stress at 10 % relative deformation,andc) when desired, the compressive modulus of rigid cellular plastics.There are two procedures: Procedure A employs crosshead motion for determination of compressive properties. Procedure A is intended
24、to be used when compressive stress at 10 % relative deformation has to be determined. Procedure B employs strain measuring devices mounted on the specimen (contact extensometer) or similar device which measures directly sample deformation. Procedure B is intended to be used when compressive modulus
25、has to be determined.NOTE Compressive strength (at maximum load) can be determined either with Procedure A and B.2 Normative referencesThe following documents, in whole or in part, are normatively referenced in this document and are indispensable for its application. For dated references, only the e
26、dition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.ISO 1923, Cellular plastics and rubbers Determination of linear dimensions3 Terms and definitionsFor the purposes of this document, the following terms and definitions apply
27、.3.1relative deformationratio of the reduction (in relation to its initial value) in thickness of the test specimen (Procedure A) or of extensometer gauge length (Procedure B)Note 1 to entry: It is expressed as a percentage.Note 2 to entry: mis the relative deformation corresponding to m(see 3.2).3.
28、2compressive strengthmmaximum compressive force Fmdivided by the initial cross-sectional area of the test specimen when the relative deformation is 10 %4DIN EN ISO 844:2014-11 EN ISO 844:2014 (E) 3.3compressive stress at 10 % relative deformation10ratio of the compressive force F10at 10 % relative d
29、eformation 10to the initial cross-sectional area of the test specimen3.4compressive modulus of elasticityEcompressive stress divided by the corresponding relative deformation below the proportional limit, i.e. when the relation is linear4 Symbols and abbreviated termsA0initial cross-sectional area,
30、in square millimetresE compressive modulus of elasticity, in megapascalsFeforce corresponding to xe(conventional proportional limit), in newtonsFmmaximum force, in newtonsF10force at 10 % relative deformation, in newtonsh0initial thickness of test specimen (Procedure A) or extensometer gauge length
31、(Procedure B), in millimetresmrelative deformation corresponding to compressive strength m, in percentmcompressive strength, in megapascals10compressive stress at 10 % relative deformation, in magapascalsxedisplacement at Fein the conventional elastic zone, in millimetresxmdisplacement at maximum fo
32、rce, in millimetresx10displacement at 10 % relative deformation, in millimetres5 PrincipleA compressive force is applied in an axial direction to the faces of test specimen.The maximum stress supported by the test specimen is calculated.If the value of the maximum stress corresponds to a relative de
33、formation of less than 10 %, it is noted as the “compressive strength”. Otherwise, the compressive stress at 10 % relative deformation is calculated and its value noted as the “compressive stress at 10 % relative deformation”.6 Apparatus6.1 Compression-testing machineUse a compression-testing machin
34、e suited to the range of force and displacement involved and having two square or circular plane, parallel plates which are polished and cannot be deformed and of which the length of one side (or the diameter) is at least 10 cm. One of the plates shall be fixed and the other 5DIN EN ISO 844:2014-11E
35、N ISO 844:2014 (E)movable; the latter shall be capable of moving at a constant rate of displacement in accordance with the conditions laid down in Clause 8. Neither plate shall be self-aligning.6.2 Devices for measuring displacement and force6.2.1 Measurement of displacementProcedure A The compressi
36、on-testing machine shall be fitted with a system allowing continuous measurement of the displacement x of the movable plate with an accuracy of 5 % or 0,1 mm if this latter value is a more accurate measurement (see second paragraph in 6.2.2).Procedure B The measure of displacement shall be obtained
37、by attaching an extensometer to the sample or by using similar devices that measure directly the sample deformation, with an accuracy of 1 %.6.2.2 Measurement of forceA force sensor shall be fixed to one of the machine plates in order to measure the force F produced by the reaction of the test speci
38、men upon the plates during the test. This sensor shall be such that its own deformation during the course of the measurement operation is negligible compared with that being measured and, in addition, it shall allow the continuous measurement of the force at any point in time with an accuracy of 1 %
39、.It is recommended that a device be used for the simultaneous recording of the force F and the displacement x that allows, by obtaining a curve of F = f(x), the graphical determination of the pair of values F, x required in Clause 9 with the accuracy laid down in 6.2.1 and this subclause, and provid
40、es additional information on the behaviour of the product.6.2.3 CalibrationDevices for measuring and, if applicable, recording graphically the force and displacement produced by the test machine shall be checked periodically. The devices shall be checked by using a series of standard weights, the ma
41、sses of which are known to accuracies better than 1 % and which correspond to the forces applied during the test. To check the devices, spacers shall be used which have thicknesses known to accuracies better than either 0,5 % or 0,1 mm, whichever is more restrictive.6.3 Instruments for measuring the
42、 dimensions of the test specimensThese instruments shall be in accordance with ISO 1923.7 Test specimens7.1 DimensionsThe test specimens shall be (50 1) mm in thickness except for products with moulded skins which are intended to remain integral with the product in use. With such products, the speci
43、mens shall be the full thickness, provided that the minimum thickness is 10 mm or greater and that the maximum thickness is not greater than the width or diameter of the specimen.The test specimen base shall be either square or circular, with a minimum area of 25 cm2and maximum of 230 cm2. The prefe
44、rred geometry and dimensions are a right prism with a base of (100 1) mm (100 1) mm.The distance between two faces shall not vary by more than 1 % (tolerance on parallelism).Under no circumstances may several test specimens be piled up to produce a greater thickness for testing.6DIN EN ISO 844:2014-
45、11 EN ISO 844:2014 (E) Since sample geometry and dimensions may have an influence on results, it is recommended to compare results only if obtained by testing samples having the same geometry and dimensions.7.2 PreparationTest specimens shall be cut so that the specimen base is normal to the directi
46、on of compression of the product in its intended use. In some cases with anisotropic materials where a more complete characterization is desired or where the principal direction of anisotropy is unknown, it may be necessary to prepare additional sets of specimens.Cutting of the test specimens shall
47、be accomplished by methods that do not change the structure of the cellular material. Moulding skins that do not remain with the product in use shall be removed.In general, any anisotropy is characterized by a plane and the direction perpendicular to this plane; thus, two sets of test specimens need
48、 to be considered.7.3 NumberRegarding the method of selecting the samples for preparation of the test specimens from the blocks or slabs of rigid cellular products and also the number of test specimens to be provided for the test, refer to the specification relating to the type of cellular product u
49、nder test. In the absence of such specifications, use at least five test specimens.7.4 ConditioningCondition the test specimens at:(23 2) C and (50 10) % relative humidityor(23 5) C and 501020+% relative humidityor(27 5) C and 651020+% relative humidityfor a minimum of 6 h.8 ProcedureThe test conditions shall be those used for conditioning the test specimens.Measure the three dimensions of each test specimen in accordance with ISO 1
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