1、Designation: D1204 14Standard Test Method forLinear Dimensional Changes of Nonrigid ThermoplasticSheeting or Film at Elevated Temperature1This standard is issued under the fixed designation D1204; the number immediately following the designation indicates the year oforiginal adoption or, in the case
2、 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.This standard has been approved for use by agencies of the U.S. Department of Defense.1. Scope*1.1 This
3、test method covers the measurement of changes inlinear dimensions of nonrigid thermoplastic sheeting or filmthat result from exposure of the material to specified conditionsof elevated temperature and time.1.2 The values stated in SI units are to be regarded as thestandard.1.3 This standard does not
4、 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.NOTE 1This test method and ISO 11501 addr
5、ess the same matter, butdiffer in technical content (and results cannot be directly comparedbetween the two methods).2. Referenced Documents2.1 ASTM Standards:2D618 Practice for Conditioning Plastics for TestingD883 Terminology Relating to PlasticsD2732 Test Method for Unrestrained Linear ThermalShr
6、inkage of Plastic Film and SheetingD4000 Classification System for Specifying Plastic Materi-als2.2 ISO StandardISO 11501 Plastics: Film and SheetingDetermination ofDimensional Change on Heating33. Terminology3.1 DefinitionsTerms applicable to this test method aredefined in Terminology D883.4. Signi
7、ficance and Use4.1 This test method is particularly applicable to nonrigidthermoplastic sheeting or film made by the calender or extru-sion process. The test gives an indication of lot-to-lot unifor-mity in regards to the degree of internal strains introducedduring processing.4.2 The heating medium
8、in this test method is air and doesnot necessarily yield the same results as Test Method D2732,which uses a liquid medium.4.3 Before proceeding with this test method, review thespecifications of the material being tested, if available.Any testspecimen preparation, conditioning, dimensions, or testin
9、gparameters, or combination thereof, covered in the relevantASTM material specification shall take precedence over thosementioned in this test method. If there are no relevant ASTMmaterial specifications, then the default conditions apply. Table1 of Classification System D4000 lists the ASTM materia
10、lstandards that currently exist.5. Apparatus5.1 OvenA mechanical convection oven capable of main-taining a temperature of 100 6 1C.5.2 Scale, graduated in 0.25-mm (0.01-in.) divisions, 30 cm(12 in.) or more in length.5.3 Thermometer, graduated in 1C divisions, with a rangesuitable for the test tempe
11、rature used.5.4 Timer, graduated in minutes.5.5 Template, 25 by 25 cm (10 by 10 in.), for cutting testspecimens.5.6 Heavy Paper Sheets, approximately 40 by 40 cm (15 by15 in.), with smooth, wrinkle- and crease-free surfaces.5.7 Talc, finely ground.1This test method is under the jurisdiction of ASTM
12、Committee D20 on Plasticsand is the direct responsibility of Subcommittee D20.19 on Film, Sheeting, andMolded Products.Current edition approved March 1, 2014. Published March 2014. Originallyapproved in 1952. Last previous edition approved in 2008 as D1204 - 08. DOI:10.1520/D1204-14.2For referenced
13、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.,
14、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 States16. Test Specimens6.1 The test specimens shall be two pieces of the shee
15、ting orfilm 25 by 25 cm (10 by 10 in.), cut with the aid of thetemplate, one from either of the two transverse edges and onefrom the center of the sheet as shown in Fig. 1. Each specimenshall be marked to show the direction of calendering orextrusion. The midpoint of each edge shall be marked for us
16、eas a reference point when final measurements are made.7. Conditioning7.1 ConditioningCondition the test specimens at 23 62C (73.4 6 3.6F) and 50 6 10 % relative humidity for notless than 40 h prior to test in accordance with Procedure A ofPractice D618 unless otherwise specified by agreement or the
17、relevant ASTM material specification. In cases ofdisagreement, the tolerances shall be 61C (61.8F) and65 % relative humidity.8. Procedure8.1 Place each specimen on the heavy paper that has beenlightly dusted with talc, and cover with a second piece ofdusted paper. Fasten the papers together with pap
18、er clips.NOTE 2The paper should be well dusted, and the specimens shouldnot be restricted either by the paper or the clips. It is imperative that thespecimens be free to change shape as strains are relieved during theperiod of test.8.2 Place the paper-plastic sandwiches horizontally in theoven at th
19、e temperature and for the length of time applicable tothe material being tested. Sandwiches must not be stacked, asthis has the potential to restrict the movement of the plasticbetween the papers.8.3 At the end of the oven-exposure period, recondition thespecimens for a minimum of1hatthetemperature
20、andhumidity used for the initial conditioning. Remove the papersand measure the distance between the opposite edges of thespecimens at the reference marks to the nearest 0.25 mm (0.01in.). Shorter reconditioning times are permissible, if it can beshown that equivalent results are obtained.9. Calcula
21、tions9.1 Calculate the linear dimensional change as follows:Linear change, % 5 Df2 Do!/Do# 3100 (1)where:Df= final length (or width) of specimen, mm (or in.) aftertest, andDo= original length (or width) of specimen, mm (or in.).A negative value denotes shrinkage, and a positive valueindicates expans
22、ion.9.2 Average the values obtained for each direction.10. Report10.1 Report the following information:10.1.1 Identification of the material tested,10.1.2 Test conditions (time and temperature), includingconditioning of test specimens, and10.1.3 Average percentage linear change in both the parallela
23、nd the transverse direction of processing.11. Precision and Bias11.1 A task group will be formed to develop the precisionand bias statement for this test method.12. Keywords12.1 film; sheeting; temperature; thermoplasticSUMMARY OF CHANGESCommittee D20 has identified the location of selected changes
24、to this standard since the last issue (D1204 - 08)that may impact the use of this standard. (March 1, 2014)(1) Removed the permissive word “may” in 4.2, 8.2, and 8.3. (2) Removed the permissive word “should” in 4.3.Points a, b and x, y are reference marks at midpoint of test specimen edges.FIG. 1 Me
25、thod of Cutting Test Specimens from SampleD1204 142ASTM 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 determination of the validity of any such patent righ
26、ts, 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 or withdrawn. Your comments are invited either for
27、revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your comments have not received a fair hearing
28、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). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).D1204 143
