1、Designation:D104212(Reapproved 2017)Standard 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 o
2、f 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.Scope1.1 This test method is designed to provide a means formeasuring in plastic specimens the dimensional ch
3、anges 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 stan
4、dard.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 to use.NOTE1There is
5、 no known ISO equivalent to this standard.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 Worl
6、d 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 Specimens3.Terminology3.1 Definitions:Definitions of terms applying to this testmethod appear in Te
7、rminology D883.4.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 are
8、rigidly 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 o
9、r 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 a
10、calibrated caliper to the nearest 0.1 mm.Thickness of arc linesshall not exceed 0.02 mm.NOTE2Phonograph needles may be 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 micro
11、meter microscopeshould be used.5.3Caliper,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 ma
12、terial that isstable under the test conditions.5.5 Room or Conditioning Chamber,capable of being main-tained at 23 6 2C and 50 6 10%RH.5.6 Conditioning Oven,full draft air-circulating oven,ca-pable of being maintained within 62C of the set temperature.5.7 Absorbent Material,cloth or paper suitable f
13、or drying.6.Test Specimens6.1 Specimens shall not be less than 110 mm in length in thedirection of test.The preferred specimen size is 125 6 5 mm1This test method is under the jurisdiction of ASTM Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.50 on Durability of Plast
14、ics.Current edition approved Aug.1,2017.Published August 2017.Originallypublished as D1042 49T.Last previous edition D1042 12.DOI:10.1520/D1042-12R17.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards
15、 volume information,refer to the standards Document Summary page onthe ASTM website.*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 i
16、n 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.1 in length by 13 6 0.5 mm wide by 3.0(-0.0+0.2)mm thick.Refer to Test Method D5947 for guidance on measuringphysical dimensions of solid plastic specimens.6.2 Three specimens shall be tested for each conditioning.6.3 Individual
