1、September 2016 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).ICS 83.060!%Zss“2558080www.din.deD
2、IN ISO 815-1Rubber, vulcanized or thermoplastic Determination of compression set Part 1: At ambient or elevated temperatures (ISO 815-1:2014),English translation of DIN ISO 815-1:2016-09Elastomere oder thermoplastische Elastomere Bestimmung des Druckverformungsrestes Teil 1: Bei Umgebungstemperature
3、n oder erhhten Temperaturen (ISO 815-1:2014),Englische bersetzung von DIN ISO 815-1:2016-09Caoutchouc vulcanis ou thermoplastique Dtermination de la dformation rmanente aprs compression Partie 1: tempratures ambiantes ou leves (ISO 815-1:2014),Traduction anglaise de DIN ISO 815-1:2016-09SupersedesDI
4、N ISO 815-1:2010-09www.beuth.deDocument comprises 17 pagesDTranslation by DIN-Sprachendienst.In case of doubt, the German-language original shall be considered authoritative.08.16 A comma is used as the decimal marker. Contents Page National foreword 3 National Annex NA (informative) Bibliography 4
5、1 Scope . 52 Normative references 53 Principle 64 Apparatus . 65 Calibration 76 Test pieces . 86.1 Dimensions . 86.2 Preparation 86.3 Number of test pieces . 86.4 Time interval between production and testing 86.5 Conditioning 97 Test conditions . 97.1 Duration of test . 97.2 Temperature of test . 98
6、 Procedure. 98.1 Preparation of compression assembly . 98.2 Thickness measurement . 98.3 Applying the compression . 108.4 Starting the test . 108.5 Terminating the test 108.6 Internal examination 109 Expression of results . 1110 Precision 1111 Test report 11Annex A (informative) Precision 13Annex B
7、(normative) Calibration schedule 15Bibliography .17DIN ISO 815-1:2016-092.National foreword This standard (ISO 815-1:2014) has been prepared by Technical Committee ISO/TC 45 “Rubber and rubber products” (Secretariat: DSM, Malaysia). The responsible German body involved in its preparation was DIN-Nor
8、menausschuss Materialprfung (DIN Standards Committee Materials Testing), 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
9、and/or DKE shall not be held responsible for identifying any or all such patent rights. Shore A hardness testing can be used as an alternative to IHRD testing to determine the compression set (the values given in 4.1.2 remain applicable; DIN ISO 7619-1 shall be applied in this case). In deviation fr
10、om ISO 815-1, 8.1, PTFE film can also be used if adhesion cannot be prevented by means of silicone oil. If PTFE film has been used, this shall be stated in the test report. The responsible committee would like to point out that the letters given in column 3 of Table B.1 (“Procedure ISO 18899:2004”)
11、are incorrect. There is an error in the ISO Standard. Also, the information in column 4 (“Verification frequency”) does not correspond to that in ISO 815-2. Both parts of the ISO Standard need to be amended. DIN ISO 815-1, Rubber, vulcanized or thermoplastic Determination of compression set Part 1:
12、Part 1: At ambient or elevated temperatures Part 2: At low temperatures The DIN Standards corresponding to the International Standards referred to in this document are as follows: ISO 4287 DIN EN ISO 4287 ISO 23529 DIN ISO 23529 Amendments This standard differs from DIN ISO 815-1:2010-09 as follows:
13、 a) normative references have been updated; b) calibration (Annex B) has been added; c) a Bibliography has been included; DIN ISO 815-1:2016-093 Previous editions DIN 53511-3: 1940x-12 DIN 53517: 1960-07, 1987-04 DIN 53517-1: 1972-01 DIN 53517-2: 1972-01 DIN ISO 815: 2000-03 DIN ISO 815-1: 2010-09 N
14、ational Annex NA (informative) Bibliography DIN EN ISO 4287, Geometrical Product Specifications (GPS) Surface texture: Profile method Terms, definitions and surface texture parameters DIN ISO 7619-1, Rubber, vulcanized or thermoplastic Determination of indentation hardness Part 1: Durometer method (
15、Shore hardness) DIN ISO 23529:2012, Rubber General procedures for preparing and conditioning test pieces for physicaltest methods DIN ISO 815-1:2016-094 Rubber, vulcanized or thermoplastic Determination of compression set Part 1: At ambient or elevated temperaturesWARNING 1 Persons using this part o
16、f ISO 815 should be familiar with normal laboratory practice. This part of ISO 815 does not purport to address all of the safety problems, 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 nati
17、onal regulatory conditions.WARNING 2 Certain procedures specified in this part of ISO 815 might involve the use or generation of substances, or the generation of waste, that could constitute a local environmental hazard. Reference should be made to appropriate documentation on safe handling and disp
18、osal after use.1 ScopeThis part of ISO 815 specifies methods for the determination of the compression set characteristics of vulcanized and thermoplastic rubbers at ambient (one method) or elevated temperatures (three methods, A, B, and C, depending on the way the test piece is released at the end o
19、f the test).The methods are intended to measure the ability of rubbers of hardness within the range 10 IRHD to 95 IRHD to retain their elastic properties at specified temperatures after prolonged compression at constant strain (normally 25 %) under one of the alternative sets of conditions described
20、. For rubber of nominal hardness 80 IRHD and above, a lower compression strain is used: 15 % for a nominal hardness from 80 IRHD to 89 IRHD and 10 % for a nominal hardness from 90 IRHD to 95 IRHD.NOTE 1 When rubber is held under compression, physical or chemical changes that prevent the rubber retur
21、ning to its original dimensions after release of the deforming force can occur. The result is a set, the magnitude of which depends on the time and temperature of compression as well as on the time, temperature, and conditions of recovery. At elevated temperatures, chemical changes become increasing
22、ly more important and lead to a permanent set.NOTE 2 Short-time compression set tests, typically for 24 h, at elevated temperatures are commonly used as a measure of the state of cure, a means of material classification, and a specification to ensure the quality of a compound. Longer tests, typicall
23、y for 1 000 h, at elevated temperatures take account of the effect of ageing and are often used to predict service performance, including that of sealing materials. Short-time tests at ambient temperature show mainly the effect of physical changes (re-orientation of the molecular chains and the fill
24、ers).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 edition cited applies. For undated references, the latest edition of the referenced document (including any a
25、mendments) applies.ISO 188, Rubber, vulcanized or thermoplastic Accelerated ageing and heat resistance testsISO 18899:2004, Rubber Guide to the calibration of test equipmentISO 23529:2010, Rubber General procedures for preparing and conditioning test pieces for physical test methodsDIN ISO 815-1:201
26、6-095 3 PrincipleA test piece of known thickness is compressed at standard laboratory temperature to a defined strain, which is then maintained constant for a specified time at standard laboratory temperature or a fixed elevated temperature. The compression is released and, after the test piece has
27、been allowed to recover at a standard laboratory temperature or the elevated temperature for a specified time, the thickness of the test piece is again measured.4 Apparatus4.1 Compression assembly, consisting of compression plates, steel spacers, and clamping device. A typical assembly is shown in F
28、igure 1.4.1.1 Compression plates, comprising a pair of parallel, flat, highly polished chromium-plated steel or highly polished stainless-steel plates, between the faces of which the test piece is compressed.The plates shall be sufficiently rigid to ensure that, with a test piece under load, no comp
29、ression plate bends by more than 0,01 mm and of sufficient size to ensure that the whole of the test piece, when compressed between the plates, remains within the area of the plates.NOTE A surface finish no worse than Ra 0,4 m (see ISO 4287) has been found to be suitable. Such an Ra can be obtained
30、by a grinding or polishing operation.4.1.2 Steel spacer(s), to provide the required compression.The spacer(s) shall be of such size and shape that contact with the compressed test piece is avoided.The height of the spacer(s) shall be chosen so that the compression applied to the test piece is (25 2)
31、 % for hardnesses below 80 IRHD, (15 2) % for hardnesses between 80 IRHD and 89 IRHD, (10 1) % for hardnesses of 90 IRHD and higher.4.1.3 Clamping device, a simple screw device (see Figure 1) is adequate.4.2 Oven, complying with the requirements specified in ISO 188, method A or method B, and capabl
32、e of maintaining the compression assembly and test pieces at the test temperature within the tolerance specified in 7.2.NOTE Test results obtained with ovens for method A can be different from those obtained with ovens for method B.The time to reach a steady-state temperature depends on the type of
33、oven and the overall heat capacity of the compression assembly. To obtain comparable results in the case of an elevated test temperature and a 24 h test duration, it is necessary to reach the steady-state temperature within the specified tolerances in the interior of the test pieces in not more than
34、 3 h.4.3 Pair of tongs, for handling the test pieces.4.4 Thickness gauge, with an accuracy of 0,01 mm (see ISO 23529:2010, 7.1), having a flat circular foot of 4,0 mm 0,5 mm in diameter and a flat solid base-plate and exerting a pressure of 22 kPa 5 kPa DIN ISO 815-1:2016-096 for solid rubber of har
35、dness equal to or greater than 35 IRHD, or a pressure of 10 kPa 2 kPa if the hardness is less than 35 IRHD.NOTE When using a digital gauge, a resolution of 0,001 mm is needed to obtain the required accuracy.After testing at elevated temperature, an unexpected deformation of the test piece is sometim
36、es observed. More particularly, the two flat surfaces can be deformed, which complicates the thickness measurement. In this case, the diameter of the gauge used to measure the thickness should be chosen carefully to allow precise measurement.4.5 Timing device, for measuring the recovery time, with a
37、 precision of 1 sa) Example 1 b) Example 2Key1 test piece 5 lower plate2 spacer 6 part formed for clamping in a device3 nut 7 locating pin4 upper plate 8 screwFigure 1 Examples of assemblies for the determination of compression set5 CalibrationThe test apparatus shall be calibrated in accordance wit
38、h the schedule given in Annex B.DIN ISO 815-1:2016-097 6 Test pieces6.1 DimensionsThe test pieces shall be one of two sizes, designated type A and type B. Type A: a cylindrical disc of diameter 29,0 mm 0,5 mm and thickness 12,5 mm 0,5 mm. Type B: a cylindrical disc of diameter 13,0 mm 0,5 mm and thi
39、ckness 6,3 mm 0,3 mm.These two types do not necessarily give the same values for compression set, and comparison of results obtained using test pieces of different sizes shall be avoided when comparing one compound with another.Type A test pieces are preferred for testing rubbers having low compress
40、ion set, because of the greater accuracy attainable using these larger test pieces.Type B test pieces are preferred when it is required to cut test pieces from products. In this case, the test pieces shall be taken as near to the centre of the product as possible, unless otherwise specified. When po
41、ssible, the test piece shall be cut in such a way that its axis is parallel to the direction of compression of the product in service.6.2 PreparationThe test pieces shall be prepared by moulding each disc, whenever possible. Preparation by cutting out each disc or by laminating not more than three d
42、iscs is permitted. The use of test pieces prepared by laminating several discs for control of finished products shall be agreed between interested parties.Cutting shall be performed in accordance with ISO 23529. When cupping (the formation of a concave surface) is a problem, the test piece shape can
43、 be improved by cutting it in two stages: first, cut an oversize test piece, and then, trim it to the exact dimensions with a second cutter.Laminated test pieces shall conform to the dimensions specified in 6.1 and shall be prepared by laminating discs or rubber cut from sheets without adhesives. Di
44、scs can be compressed by a few percent for 1 min so that they stick together. The number of discs laminated to produce a test piece shall not exceed three. The total thickness shall then be measured.Test pieces prepared by the various methods described above can give different results and comparison
45、 of values shall be avoided.NOTE Attention is drawn to the marked effects of the state of cure on compression set values. It might be necessary to adjust the cure of moulded test pieces to be representative of different thicknesses of sheets or mouldings.6.3 Number of test piecesA minimum of three t
46、est pieces shall be tested, separately or as a set.6.4 Time interval between production and testingFor all test purposes, the minimum time between production and testing shall be 16 h.For non-product tests, the maximum time between production and testing shall be 4 weeks and, for evaluations intende
47、d to be comparable, the tests, as far as possible, shall be carried out after the same time interval.For product tests, whenever possible, the time between production and testing shall not exceed three months. In other cases, tests shall be made within two months of the date of receipt of the product by the purchaser (see ISO 23529).DIN ISO 815-1:2016-098 6.5 ConditioningSamples and test pieces shall be protected from light and heat as much as possible during the interval between production and testing.Prepared test pieces shall be conditioned immediate
