ASTM_D_1042_-_22.pdf

Designation:D104222Standard Test Method forLinear Dimensional Changes of Plastics Caused byExposure to Heat and Moisture1This standard is issued under the fixed designation D1042;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope*1.1 This test method is designed to provide a means formeasuring the dimensional changes of plastic specimens suchas shrinkage or expansion,developed under specific heat andwater conditionings.1.2 The values stated in SI units are to be regarded asstandard.The values given in parentheses are mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standard.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,health,and environmental practices and deter-mine the applicability of regulatory limitations prior to use.NOTE1This standard and ISO 2796 address the same subject matterbut differ in technical content.1.4 This international standard was developed in accor-dance with internationally recognized principles on standard-ization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recom-mendations issued by the World Trade Organization TechnicalBarriers to Trade(TBT)Committee.2.Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsD5947 Test Methods for Physical Dimensions of SolidPlastics SpecimensE456 Terminology Relating to Quality and StatisticsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test MethodE2935 Practice for Evaluating Equivalence of Two TestingProcesses2.2 ISO Standards:3ISO 2796 Cellular plastics,rigidTest for dimensional sta-bility3.Terminology3.1 Definitions:3.1.1 For definitions of terms that appear in this practicerelating to plastics,refer to Terminology D883.3.1.2 For definitions of terms that appear in this practicerelating to quality and statistics(such as precision and bias),refer to Terminology E456.4.Significance and Use4.1 This test method is intended only as a convenient testmethod for measurement of linear dimensional changes inplastics subjected to defined conditions of test as outlined inSections 7 and 8.5.Apparatus5.1 Scriber,so constructed that two sharp needle points arerigidly separated by 100 6 0.2 mm.The scriber,as shown inFig.1,consists of two sharp steel needles,approximately 1.5mm in diameter.The needles are to be inserted in drilled holeswith their axes parallel to each other and perpendicular to andintersecting the long axis of a stainless steel rigid rod or barstock,125 6 5 mm in length.The needles points shall extend6 6 2 mm beyond the supporting rod and are held in positionby setscrews inserted through the ends of the rod.The scribershall be calibrated by scribing an arc onto an unconditionedsample and measuring this initial scribed distance with acalibrated caliper to the nearest 0.1 mm.Thickness of arc linesshall not exceed 0.02 mm.NOTE2Phonograph needles have been used as a satisfactory scriber.5.2 Measuring Microscope,having a magnification of atleast 20 and graduated to have a resolution of 0.01 mm.NOTE3For more precise measurements,a micrometer microscope ispreferred.1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.50 on Durability of Plastics.Current edition approved May 1,2022.Published May 2022.Originallyapproved in 1949.Last previous edition approved in 2017 as D1042 12(2017).DOI:10.1520/D1042-22.2For 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 Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United StatesThis international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for theDevelopment of International Standards,Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade(TBT)Committee.15.3Caliper,6-in.,with a readability of 0.01 mm and anilluminated desk magnifier,1.75 to 2.0 to assist with theplacement of the caliper points onto the scribed lines5.4 Beaker,having a suitable size for the number of speci-mens to be evaluated and is constructed of a material that isstable under