1、Designation: D 2126 04Standard 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 (e) 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 can be found inTable 1.1.2 The values stated in SI units are to be regarded as thestandard. The values in brackets a
4、re 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 prio
5、r to use.NOTE 2This test method resembles ISO 2796 in title only. Thecontent is significantly different. This test method is equivalent to ISO2796 in the sampling and calculation sections. It is not equivalent to ISO2796 in the procedure section.2. Referenced Documents2.1 ASTM Standards:2D 883 Termi
6、nology Relating to PlasticsD 1037 Test Methods for Evaluating the Properties ofWood-Base Fiber 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. Signif
7、icance and Use4.1 Because of the wide variety of potential uses of rigidcellular plastics, artificial 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 con
8、ditions from which oneor more of the desired exposure conditions can be selected.(Note 3)4.2 The 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. Fi
9、nal test measurements aredetermined after the specimens return to room temperature.Where specified, 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 particu
10、larenvironment, to assess the relative stability of two or morecellular plastics, or to specify 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 d
11、esigncalculations.NOTE 3Where thermal shock is known or suspected to occur due torapid heating 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
12、 a specimen can vary dependingupon the age of the sample or the length of time between specimenpreparation and the beginning of the test, or both.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.22 on Cellular Materials
13、Plastics and Elastomers.Current edition approved November 1, 2004. Published December 2004.Originally approved in 1962. Last previous edition approved in 1999 as D 2126 -99.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For A
14、nnual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036.TABLE 1 Temperature and Relative Humidity ConditionsTemperature, C F Relative Hum
15、idity, %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 ambient23 6 2736 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 thi
16、s standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4.4 Before proceeding with this test method, reference shallbe made to the specification of the material being tested. Anytest specimen preparation, conditioning, dimensions,
17、or testingparameters covered in the materials specification, 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 mas
18、s of 100 g or less.5.2 Oven, circulating-air, capable of 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 cm21in.2(Note 5). A vernier caliper having
19、graduations not largerthan 0.1 mm 0.005 in. can 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 main
20、taining 63 % humid-ity, and the required temperature 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 pe
21、rmitted. Dust shall be blown off the specimens.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 sp
22、ecimens, but preferably three ormore specimens, 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, c
23、ondition specimens at least to a con-stant mass at 23 6 2C 73.4 6 4F and 50 6 5 % 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
24、axes to the nearest 60.1 %. For standard-size 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 th
25、e specified aging conditions.8.2 Expose the 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 circulatio
26、n around the test specimensoccur.8.2.1 Expose 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 d
27、ifference between continu-ous exposure and 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
28、in general appear-ance at each stage of the 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
29、100 (1)where:mf= final measurement, andmo= 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 per
30、centage changes to the nearest0.1 % of length, 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 t
31、herespective standard deviation at each exposure 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-la
32、boratory round robin at three different test 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
33、within 1.1 % for the same material and conditions. 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 alaboratory, and by up to 5.6 % linear change between lab
34、ora-tories (95 % confidence). Percent change in mass differed byD21260423.9 % 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 chang
35、e; dimensional stability; humid ag-ing; rigid cellular plastics; thermal agingSUMMARY OF CHANGESCommittee D20 has identified the location of selected changes to this standard since the last issue,D 2126 - 99, that may impact the use of this standard. (November 1, 2004)(1) Removed permissive language
36、 from several sections.(2) Revised 8.1.2 to require only one measurement per direc-tion, and to clarify where measurement shall be taken.(3) Added term: “dimensional stability” to Keywords.ASTM International takes no position respecting the validity of any patent rights asserted in connection with a
37、ny item mentionedin this standard. Users of this standard are expressly advised that determination 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 technica
38、l committee and must be reviewed every five years andif not revised, either reapproved or withdrawn. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration
39、at a meeting of theresponsible technical committee, which you may attend. If you feel 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
40、 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).D2126043
