1、Designation: D 2126 09Standard Test Method forResponse of Rigid Cellular Plastics to Thermal and HumidAging1This standard is issued under the fixed designation D 2126; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of las
2、t revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope*1.1 This test method covers procedures for
3、the thermal andhumid exposure of rigid cellular plastics. Conditions used shallbe agreed upon between the purchaser and the supplier.NOTE 1A list of commonly used exposure conditions is found inTable 1.1.2 The values stated in SI units are to be regarded as thestandard. The values in parentheses are
4、 for information only.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to establish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior
5、to use.NOTE 2This test method is equivalent to ISO 2796 in the samplingand calculation sections. It is not equivalent to ISO 2796 in the proceduresection.2. Referenced Documents2.1 ASTM Standards:2D 883 Terminology Relating to PlasticsD 1037 Test Methods for Evaluating Properties of Wood-Base Fiber
6、and Particle Panel Materials2.2 ISO Standard:ISO 2796 Cellular Plastics RigidTest for DimensionalStability33. Terminology3.1 The terms given in Terminology D 883 are applicable tothis test method.4. Significance and Use4.1 Because of the wide variety of potential uses of rigidcellular plastics, arti
7、ficial exposure to estimate the effectivebehavior of these materials must be based, to a great extent, onthe intended application. Toward this end, this test method isintended to recommend a variety of conditions from which oneor more of the desired exposure conditions can be selected.(Note 3)4.2 Th
8、e conditions recommended in this test method havebeen widely used in artificially exposing rigid cellular plasticsand in determining the effects of various temperatures andhumidities on these materials. Final test measurements aredetermined after the specimens return to room temperature.Where specif
9、ied, the specimens will be tested at the exposurecondition, but must be reported as such.4.3 Dimensional changes measured by this test method canbe used to compare the performance of materials in a particularenvironment, to assess the relative stability of two or morecellular plastics, or to specify
10、 an acceptance criterion for aparticular material. The results of this test method are notsuitable for predicting end-use product performance or char-acteristics, nor are they adequate for engineering or designcalculations.NOTE 3Where thermal shock is known or suspected to occur due torapid heating
11、to (or cooling from) a particular temperature, guidance onthe permissible heating or cooling rates, or both, shall be obtained fromthe manufacturer of the material concerned.NOTE 4The dimensional change of a specimen can vary dependingupon the age of the sample or the length of time between specimen
12、1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.22 on Cellular Materials -Plastics and Elastomers.Current edition approved Sept. 1, 2009. Published September 2009. Originallyapproved in 1962. Last previous edition appr
13、oved in 2004 as D 2126 - 04.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National
14、 Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.TABLE 1 Temperature and Relative Humidity ConditionsTemperature, C (F) Relative Humidity, %73 6 3 (100 6 6) ambient40 6 3 (40 6 6) ambient70 6 2 (158 6 4) ambient100 6 2 (212 6 4) ambient150 6 2 (302 6 4) a
15、mbient23 6 2(736 4) 50 6 538 6 2 (100.0 6 4) 97 6 370 6 2 (158 6 4) 97 6 3other temperatures and humidities selected for individual needs1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-29
16、59, United States.preparation and the beginning of the test, or both.4.4 Before proceeding with this test method, reference shallbe made to the specification of the material being tested. Anytest specimen preparation, conditioning, dimensions, or testingparameters covered in the materials specificat
17、ion, or combina-tion thereof, shall take precedence over those mentioned in thistest method. If there are no specifications, then the defaultconditions apply.5. Apparatus5.1 Balance, capable of weighing, to 0.05 %, a test speci-men having a mass of 100 g or less.5.2 Oven, circulating-air, capable of
18、 holding the requiredtemperature of exposure within 62C (4F).5.3 Cold Box, capable of maintaining the required tempera-ture of exposure within 63C (5F).5.4 Gage, dial-type, with a minimum foot area of 6.5 cm2(1in.2)(Note 5). A vernier caliper having graduations not largerthan 0.1 mm (0.005 in.) can
19、also be used. Care shall be takenthat the specimen is not crushed in any way, regardless ofwhich instrument is used.NOTE 5A dial gage comparator for determining linear variations isillustrated in Test Methods D 1037.5.5 Humidity Oven, suitable for maintaining 63 % humid-ity, and the required tempera
20、ture within 62C (4F).6. Sampling, Test Specimens, and Test Units6.1 Test specimens shall be machined or sawed from thesample so as to have smooth edges free of cracks. All faces ofthe specimen shall be smooth. Finishing with No. 0 or finersandpaper is permitted. Dust shall be blown off the specimens
21、.6.2 Test specimens shall have minimum dimensions of 100by 100 mm by thickness supplied (4 by 4 in. by thicknesssupplied). Materials with and intended for use with natural orlaminated skin surfaces shall be tested with skins intact.6.3 A minimum of two specimens, but preferably three ormore specimen
22、s, shall be used for each exposure condition.6.4 Where destructive tests are to be made, several sets ofspecimens shall be used at the specified conditions.7. Conditioning7.1 Unless otherwise specified, by the contract or relevantmaterial specification, condition specimens at least to a con-stant ma
23、ss at 23 6 2C (73.4 6 4F) and 50 6 10 % relativehumidity before exposure.8. Procedure8.1 Make the following measurements after conditioning.8.1.1 MassDetermine mass, when specified, within0.05 %.8.1.2 DimensionsDetermine the dimensions of the threeprincipal axes to the nearest 60.1 %. For standard-s
24、ize speci-mens, make one measurement per dimension at the approxi-mate center of each face. If larger specimens are used, makethree measurements of length and width, and five measure-ments of thickness. If specimens distort, report them asdistorting under the specified aging conditions.8.2 Expose th
25、e test specimens conditioned in accordancewith 7.1 in a circulating air oven, humidity oven, or cold boxmaintained at one of the combinations of temperature andrelative humidity shown in Table 1. Care shall be taken suchthat substantially free air circulation around the test specimensoccur.8.2.1 Exp
26、ose the specimen at this condition for 24 h (oneday) 6 1 h, 168 h (one week) 6 2 h, and 336 h (two weeks)6 2 h. Intermediate observations are recommended to serve asa guide to full-term performance. A round-robin study hasshown that there is no significant difference between continu-ous exposure and
27、 exposure interrupted for up to4hformeasuring purposes.8.2.2 After exposure, allow the specimens to come to roomtemperature for 2 h before measuring and testing.8.2.3 Measure specimen dimensions as described in section8.1.8.3 Visual ExaminationRecord change in general appear-ance at each stage of th
28、e testing procedure. (Use the termsdefined in Terminology D 883 to describe defects.)9. Calculation9.1 Calculate the changes in dimensions (and mass, whenspecified), expressed as a percentage of the original measure-ment, as follows:change, % 5 mf mo!/mo# 3 100 (1)where:mf= final measurement, andmo=
29、 original measurement.10. Report10.1 Report the following information:10.1.1 Description of specimens, including type of material,anisotropy, and history if known,10.1.2 Specific conditions used,10.1.3 If two specimens were tested:10.1.3.1 The individual percentage changes to the nearest0.1 % of len
30、gth, width, thickness, and mass (when specified) ofeach test specimen at each exposure period.10.1.4 If three or more specimens were tested:10.1.4.1 The mean percentage changes to the nearest 0.1 %of length, width, thickness, and mass (when specified), and therespective standard deviation at each ex
31、posure period.10.1.5 Description of changes in appearance.11. Precision and Bias11.1 PrecisionThe interlaboratory and intralaboratoryprecision of this test method can be expected to vary withmaterial, test condition, and sample direction. Results of afive-laboratory round robin at three different te
32、st conditionsshowed that for certain materials, percent linear change mea-surements can be expected to agree within 0.9 % linear change(at 95 % confidence), both within a single laboratory andbetween laboratories. Percent mass change can be expected toagree within 1.1 % for the same material and con
33、ditions. Othermaterials may show substantially greater variability not relatedto the test procedure. Percent linear change for one round-robinmaterial differed by as much as 1.5 % linear change within aD2126092laboratory, and by up to 5.6 % linear change between labora-tories (95 % confidence). Perc
34、ent change in mass differed by3.9 % mass change within laboratories and 5.1 % mass changebetween laboratories for the most variable material (95 %confidence).11.2 BiasThe bias for this test method has not yet beendetermined.12. Keywords12.1 dimensional change; dimensional stability; humid ag-ing; ri
35、gid cellular plastics; thermal agingSUMMARY OF CHANGESCommittee D20 has identified the location of selected changes to this standard since the last issue,D 2126 - 04, that may impact the use of this standard. (September 1, 2009)(1) Removed permissive language in Note 1.(2) RevisedNote 2 to conform w
36、ith Guide D 4968 format.(3) Changed the tolerance of the relative humidity duringconditioning to 610 %.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that d
37、etermination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved
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39、that your comments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org).D2126093
