TM_D_5945_
_96
Designation:D 5945 96Standard Test Method forDetermining Temperature of Deflection of Plastics andEbonite Under Load1This standard is issued under the fixed designation D 5945;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(e)indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers three procedures for determi-nation of the temperature of deflection under load(bendingstress)of plastics and ebonite:1.1.1 Test Method A,using a nominal surface stress of 1.80MPa;1.1.2 Test Method B,using a nominal surface stress of 0.45MPa;and1.1.3 Test Method C,using a nominal surface stress of 8.00MPa.1.2 The test specimens are tested in one of two positions,flatwise or edgewise,with the requirements on test specimendimensions being different in each case(see Guide D 5944,Section 6).1.3 See Guide D 5944,1.3.NOTE1The test methods give better reproducibility with amorphousplastics than with semi-crystalline ones.With some materials,it may benecessary to anneal the test specimens to obtain reliable results.If applied,annealing procedures generally result in an increase in the temperature ofdeflection under load(see 7.2 and 7.3).1.4 This test method is identical to ISO 75-2.This testmethod is comparable to Test Method D 648,but neither testmethod should be substituted for the other.The two testmethods may differ with respect to test specimen dimensions,test specimen conditioning,test equipment,testing conditions,etc.The two test methods may not give the same results.1.5 The values stated in SI units are to be regarded as thestandard.The values given in parentheses are for informationonly.1.6 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.2.Referenced Documents2.1 ASTM Standards:D 648 Test Method for Deflection Temperature of PlasticsUnder Flexural Load2D 5936 Specification for Multipurpose Test SpecimensUsed for Testing Plastics3D 5939 Practice for Preparing Multipurpose Test Specimensand Bars of Thermoplastics by Injection Moulding3D 5940 Practice for Preparing Small Plate Test Specimensof Thermoplastics by Injection Moulding3D 5944 Guide for Describing the General Principles forDetermining the Temperature of Deflection of PlasticsUnder Load32.2ISO Standards:4ISO 75-2 Determination of Temperature of Deflection Un-der LoadPart 2:Plastics and EboniteISO 293:1986,PlasticsCompression Moulding TestSpecimens of Thermoplastic MaterialsISO 294,PlasticsInjection Moulding of Test Specimensof Thermoplastic MaterialsISO 2818,PlasticsPreparation of Test Specimens by Ma-chiningISO 3167:1993,PlasticsMultipurpose Test Specimens3.Terminology3.1 DefinitionsSee Guide D 5944,Section 3.4.Principle4.1 A standard test specimen made of plastic or ebonite issubjected to a bending stress to produce one of the nominalsurface stresses given in 1.1.The temperature is raised at auniform rate,and the temperature at which a specified deflec-tion occurs is measured.5.6.Apparatus6.1 Means of Applying a Bending Stress:6.1.1 See Guide D 5944,6.1.6.1.2 The span between the test specimen supports shall be64 6 1 mm if the specimen is tested in the flatwise position and100 6 2 mm if the specimen is tested in the edgewise position.6.2 Heating EquipmentSee Guide D 5944,6.2.1Bias This test method is under the jurisdiction of ASTM Committee D-20 onPlastics and is the direct responsibility of Subcommittee D20.61 on USA TechnicalAdvisory Group for ISO/TC 61 on Plastics.Current edition approved June 10,1996.Published August 1996.2Annual Book of ASTM Standards,Vol 08.01.3Annual Book of ASTM Standards,Vol 08.03.4Available from American National Standards Institute,11 W.42nd St.,13thFloor,New York,NY 10036.1AMERICAN SOCIETY FOR TESTING AND MATERIALS100 Barr Harbor Dr.,West Conshohocken,PA 19428Reprinted from the Annual Book of ASTM Standards.Copyright ASTMNOTICE:This standard has either been superseded and replaced by a new version or discontinued.Contact ASTM International(www.astm.org)for the latest information.6.3 WeightsSee Guide D 5944,6.3.6.4Temperature-MeasuringInstrumentSeeGuideD 5944,6.4.6.5 Deflection-Measuring InstrumentSee Guide D 5944,6.5.7.Test Specimens7.1 See Guide D 5944,Section 6.7.2 One of two different types of test specimens shall beused,depending on the orientation of the specimen in the testapparatus.7.2.1 If the specimen is tested in the flatwise position,itsdimensions shall be as follows:Length,l,80 6 2.0 mmWidth,b,10 6 0.2 mmThickness,h,4 6 0.2 mm7.2.2 If the specimen is tested in the edgewise position,itsdimensions shall be as follows:Length,l,120.0 6 10.0 mmWidth,b,9.8 to 15.0 mmThickness,h,3.0 to 4.2 mm7.