1、December 2013Translation 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 83.060!%*c2“2076415www.din.deDDIN ISO 2285Rubber, vulcanized or thermoplastic Determination of tension set under constant elongation, and of tensionset, elongation and creep under constant tensile load (ISO 2285:2013),English translation of DIN ISO 2285:2013-12Elastomere oder thermoplastische Elas
3、tomere Bestimmung des Zugverformungsrestes unter konstanter Dehnung und desZugverformungsrestes, der Dehnung und des Flieens unter konstanter Zugbelastung(ISO 2285:2013),Englische bersetzung von DIN ISO 2285:2013-12Caoutchouc vulcanis ou thermoplastique Dtermination de la dformation rmanente sous al
4、longement constant et de ladformation rmanente, de lallongement et du fluage sous charge constante de traction(ISO 2285:2013),Traduction anglaise de DIN ISO 2285:2013-12SupersedesDIN ISO 2285:2010-07www.beuth.deIn case of doubt, the German-language original shall be considered authoritative.Document
5、 comprises 17 pages11.13 A comma is used as the decimal marker. Contents Page National foreword .3 National Annex NA (informative) Bibliography .4 1 Scope .5 2 Normative references .5 3 Terms and definitions 6 4 Apparatus 6 4.1 Constant-elongation measurements 6 4.2 Constant-load measurements .7 5 C
6、alibration .8 6 Test pieces 8 6.1 Preparation 8 6.2 Test pieces for testing under constant elongation .8 6.3 Test pieces for testing under constant load 9 6.4 Marking 9 6.5 Number of test pieces 9 6.6 Time interval between forming and testing .9 6.7 Conditioning. 10 7 Procedure . 10 7.1 Testing unde
7、r constant elongation 10 7.2 Testing under constant load . 12 8 Expression of results 12 8.1 General . 12 8.2 Constant elongation 12 8.3 Constant load . 13 9 Test report 13 Annex A (normative) Calibration schedule . 15 Bibliography . 17 DIN ISO 2285:2013-122National foreword This standard (ISO 2285:
8、2013) has been prepared by Technical Committee ISO/TC 45 “Rubber and rubber products” (Secretariat: DSM, Malaysia), Subcommittee SC 2 “Testing and analysis” (Secretariat: JISC, Japan). The responsible German body involved in its preparation was the Normenausschuss Materialprfung (Materials Testing S
9、tandards Committee), Working Committee NA 062-04-34 AA Prfung der physikalischen Eigenschaften von Kautschuk und Elastomeren. Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. DIN and/or DKE shall not be held responsible for identif
10、ying any or all such patent rights. Re Subclause 6.1.3.1 In the literature, the length difference in relation to the initial length is usually designated by the symbol and the ratio final length to initial length is designated by the symbol . The DIN Standards corresponding to the International Stan
11、dards referred to in this document are as follows: ISO 815-1 DIN ISO 815-1 ISO 23529 DIN ISO 23529 Amendments This standard differs from DIN ISO 2285:2010-07 as follows: a) the procedure of methods A, B and C have been changed; b) Annex A “Calibration schedule” has been added. Previous editions DIN
12、53511-1: 1940-12 DIN 53511-2: 1940-12 DIN 53518:1965-09, 1979-03 DIN ISO 2285: 1994-05, 2003-07, 2010-07 DIN ISO 2285:2013-123National Annex NA (informative) Bibliography DIN ISO 815-1, Rubber, vulcanized or thermoplastic Determination of compression set Part 1: At ambient or elevated temperatures D
13、IN ISO 23529, Rubber General procedures for preparing and conditioning test pieces for physical test methods DIN ISO 2285:2013-124WARNING Persons using this International Standard should be familiar with normal laboratory practice. This standard does not purport to address all of the safety problems
14、, if any, associated with its use. It is the responsibility of the user to establish appropriate safety and health practices and to ensure compliance with any national regulatory conditions.CAUTION Certain procedures specified in this International Standard might involve the use or generation of sub
15、stances, or the generation of waste, that could constitute a local environmental hazard. Reference should be made to appropriate documentation on safe handling and disposal after use.1 ScopeThis International Standard specifies a number of methods of determining the dimensional changes in test piece
16、s of vulcanized or thermoplastic rubber during and after tensile loading for relatively short periods under constant elongation or constant loading.The constant-elongation test is intended to measure the ability of rubbers to retain their elastic properties after extension, at a standard laboratory
17、temperature, to a specified strain which is maintained for a specified time at the same or at a specified higher temperature and then released at the test temperature or at the standard laboratory temperature.The constant-load test specifies a method for the determination of elongation, creep and te
18、nsion set of rubbers subjected to a constant load at standard laboratory temperature.The test methods are intended to measure the elastic properties of rubber in the hardness range 20 IRHD to 94 IRHD.The creep measurement is not recommended for product design or the evaluation of low-creep materials
19、. For these, reference should be made to ISO 8013. No agreement between the results of this test and those of ISO 8013 should be inferred.NOTE The constant-load test is primarily intended for the measurement of state of cure and the quality control of thin-walled products. An increase in the state o
20、f cure or degree of crosslinking is usually reflected in a decrease in set, creep or elongation.2 Normative referencesThe following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest ed
21、ition of the referenced document (including any amendments) applies.ISO 188, Rubber, vulcanized or thermoplastic Accelerated ageing and heat resistance testsISO 8013, Rubber, vulcanized Determination of creep in compression or shearISO 18899:2004, Rubber Guide to the calibration of test equipmentISO
22、 23529:2010, Rubber General procedures for preparing and conditioning test pieces for physical test methodsRubber, vulcanized or thermoplastic Determination of tension set under constant elongation, and of tension set, elongation and creep under constant tensile load DIN ISO 2285:2013-1253 Terms and
23、 definitionsFor the purposes of this document, the following terms and definitions apply (see also the definitions of creep functions given in ISO 8013).3.1tension set at constant loadelongation remaining in a test piece in the unloaded condition after it has been subjected to a constant load during
24、 a specified time, expressed as a percentage of the original length in the unloaded condition3.2tension set at constant elongationelongation remaining in a test piece in the relaxed condition after it has been subjected to a constant elongation during a specified time, expressed as a percentage of t
25、he elongation3.3creepincrease in elongation of a test piece at constant load during a specified time, expressed as a percentage of the elongation at the beginning of that time4 Apparatus4.1 Constant-elongation measurements4.1.1 Straining device, consisting of a metal rod or other suitable guide fitt
26、ed with pairs of holders, one fixed and one moveable, for the ends of the test piece. The holders shall be in the form of self-tightening clamps for strip test pieces, in the form of jaws to hold tab (enlarged) ends, and in the form of flat pulleys of about 5 mm width and 10 mm diameter for ring tes
27、t pieces.If so desired, a means of operating the moving holder other than by hand may be provided, for example a threaded rod. Suitable stops or graduations may also be provided to avoid over-extension in the initial straining of the test piece.The straining device shall be so designed that, when us
28、ed at high temperatures in an oven, it can be placed with the reference length of the test piece perpendicular to the direction of the air flow. It shall also be of minimum mass in order to avoid excessive lag in the attainment of temperature equilibrium after its introduction into the oven.A multip
29、le-unit straining device may be used, provided that the foregoing requirements are met.4.1.2 Oven, conforming to the requirements of ISO 188 (if the test is to be carried out at a temperature above the standard laboratory temperature). For short heating times, controlled air flow is not necessary.4.
30、1.3 Length-measuring device, capable of measuring the reference length of the test piece to the nearest 0,1 mm.For strip test pieces, a marker shall be provided to mark the length used as the reference length.For ring test pieces, the reference length may be the inner diameter of the ring, in which
31、case a graduated cone allowing measurements to be made to the nearest 0,1 mm shall be used. Alternatively, if measurements are to be made on a straight reference length, a rigid channel, 3,5 mm deep and 20 mm wide for large ring test pieces and 1,75 mm deep and 10 mm wide for small ring test pieces,
32、 shall be provided for straightening portions of such test pieces during marking and measuring of the reference length.DIN ISO 2285:2013-1264.2 Constant-load measurements4.2.1 Straining device, comprising clamps and weights, or equivalent, for loading the test pieces (see Figure 1).Key1 fixed clamp2
33、 test piece3 clamp for holding weight4 weightFigure 1 Straining device4.2.2 Thickness- and width-measuring device, comprising a gauge for measuring the thickness and, where appropriate, the width of the test piece in accordance with ISO 23529:2010, method A.The width of die-cut test pieces shall be
34、taken as the distance between the cutting edges of the die in the narrow part, in which case a device capable of measuring the width to the nearest 0,05 mm in accordance with ISO 23529 shall be provided.4.2.3 Length-measuring device, capable of measuring the reference length to the nearest 0,1 mm.DI
35、N ISO 2285:2013-1275 CalibrationThe test apparatus shall be calibrated in accordance with the schedule given in Annex A.6 Test pieces6.1 PreparationTest pieces shall be prepared in accordance with ISO 23529. They shall be cut from flat sheet 2 mm 0,2 mm thick (except large ring test pieces, which sh
36、all be cut from sheet 4 mm 0,2 mm thick) prepared by moulding or slitting and buffing in accordance with ISO 23529.Strip test pieces and strip test pieces with enlarged ends shall be cut using a sharp die with a cutter as specified in ISO 23529.Ring test pieces shall be cut from sheet by means of a
37、pair of concentric circular dies or rotating cutters. The separation of the two cutting edges shall not differ from the average value by more than 0,05 mm.6.2 Test pieces for testing under constant elongation6.2.1 Strip test piecesStrip test pieces shall be between 2 mm and 10 mm wide. A width of 6
38、mm is preferred.The length of any given strip depends on the selected reference length and the type of straining device.6.2.2 Strip test pieces with enlarged endsTest pieces with enlarged ends shall be as shown in Figure 2, with a narrow section of length between 25 mm and 50 mm which shall be used
39、as the reference length.Dimensions in millimetresThickness 2 mm 0,2 mmFigure 2 Test piece with enlarged ends6.2.3 Ring test piecesRing test pieces shall be of one of the following sizes:Large ring test piece: thickness: 4 mm 0,2 mm; outer diameter: 52,6 mm 0,2 mm; inner diameter: 44,6 mm 0,2 mm.DIN
40、ISO 2285:2013-128Small ring test piece: thickness: 2 mm 0,2 mm; outer diameter: 33,5 mm 0,2 mm; inner diameter: 29,5 mm 0,2 mm.6.3 Test pieces for testing under constant loadTest pieces shall have the shape and dimensions shown in Figure 3.Dimensions in millimetresThickness 2 mm 0,2 mmFigure 3 Test
41、piece for constant loading6.4 Marking6.4.1 GeneralReference marks shall be marked on the test pieces, using a suitable marker and an ink which does not affect the material and withstands the temperature of test.6.4.2 Tests at constant elongationThe reference length shall be between 25 mm and 50 mm,
42、measured between the inner sides of the marks. For strip test pieces, the preferred length is 50 mm. Ring test pieces shall be straightened by means of a rigid channel (see 4.1.3) and the reference length, preferably 40 mm for large ring test pieces and 25 mm for small ring test pieces, shall be mar
43、ked on one of the straightened sides.6.4.3 Tests at constant loadTwo reference marks shall be marked on the central part of the test piece at a distance of 90 mm 0,5 mm from each other.6.5 Number of test piecesFor each test, a minimum of three test pieces shall be used. (For material with a calender
44、ing grain, three test pieces shall be taken in each of two directions at right angles to each other.)6.6 Time interval between forming and testingThe time interval between forming and testing shall be in accordance with ISO 23529.DIN ISO 2285:2013-129Samples and test pieces shall be protected from l
45、ight as completely as possible during the interval between forming and testing.6.7 ConditioningPrepared test pieces shall be conditioned immediately before testing for a minimum period of 3 h at one of the standard laboratory temperatures defined in ISO 23529, the same temperature being used through
46、out any one test or series of tests intended to be comparable.7 Procedure7.1 Testing under constant elongation7.1.1 Measurement of the test piecesMeasure the unstrained reference length (L1) of each test piece to the nearest 0,1 mm at standard laboratory temperature. Insert the test pieces in the st
47、raining device in the appropriate way.7.1.2 Stretching the test piecesExtend the test pieces to the required strain. When testing ring test pieces, rotate the pulleys slightly by hand to equalize the strain in the two halves of the ring. Ensure that the reference length remains centralized between t
48、he two pulleys.Between 10 min and 20 min after the specified strain has been reached, measure the strained reference length (L2) to the nearest 0,1 mm. When the inner diameter of ring test pieces is used as the reference length, it can be calculated from the diameter of the pulleys and the distance
49、between them, measured to the nearest 0,1 mm. If the strain, calculated as specified in 7.1.4.1, does not conform to the appropriate standard value, taking into account tolerances, discard the test piece and prepare and test a replacement test piece with a modified applied strain.7.1.3 Exposure at the test temperature7.1.3.1 Tests at standard laboratory temperatureMaintain the strained test pieces at the standard laboratory temperature.Imme
