ASTM_D_8289_-_20.pdf

Designation:D828920Standard Test Method forTensile Strength Estimate by Disc Compression ofManufactured Graphite1This standard is issued under the fixed designation D8289;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 covers testing apparatus,specimenpreparation,and testing procedures for determining the split-ting tensile strength of graphite by diametral line compressionof a disk.This small specimen geometry(Test Method D7779)is specifically intended for irradiation capsule use.Users arecautioned to use Test Method C749 if possible for measuringtensile strength properties of graphite.1.2 The values stated in SI units are to be regarded asstandard.The values given in parentheses after SI units areprovided for information only and are not considered standard.1.3 All dimension and force measurements and stress cal-culations shall conform to the guidelines for significant digitsand rounding established in Practice D6026.1.4 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.1.5 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:2C749 Test Method for Tensile Stress-Strain of Carbon andGraphiteD4175 Terminology Relating to Petroleum Products,LiquidFuels,and LubricantsD6026 Practice for Using Significant Digits in GeotechnicalDataD7542 Test Method forAir Oxidation of Carbon and Graph-ite in the Kinetic RegimeD7775 Guide for Measurements on Small Graphite Speci-mensD7779 Test Method for Determination of Fracture Tough-ness of Graphite at Ambient TemperatureE4 Practices for Force Verification of Testing MachinesE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 Refer to Terminology D4175 for specific definitions.3.2 Definitions of Terms Specific to This Standard:3.2.1 splitting tensile strength,nthe tensile strength of amaterial estimated from a splitting compressive configurationsuch as that described here.4.Significance and Use4.1 By definition,the tensile strength of manufacturedgraphite is obtained by the direct uniaxial tensile test(TestMethod C749).The C749 tensile test specimen is relativelylarge and is frequently incompatible with available irradiationcapsule volumes,or oxidation apparatus(Test Method D7542).The splitting tensile test provides an alternate means of testingtensile properties on specimens that have severe geometricconstraints and otherwise cannot meet the prescribed testinggeometries of Test Method C749.By loading a disc-shapedspecimen,on edge,under a compressive load,the resultingtensile stresses transverse to the loading axis provide anindication of the tensile strength properties of graphite.Toobtain consistent and meaningful values of a splitting tensilestrength,it is vital that the fracture initiate in the center of thedisk and not along an edge.This standard test helps to ensurethat the disk specimens break diametrally along the loadingdiameter due to tensile stresses that are perpendicular to theloading axis and that the fracture initiates at the center of thedisk.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibility ofSubcommittee D02.F0 on Manufactured Carbon and Graphite Products.Current edition approved May 1,2020.Published June 2020.Originallyapproved in 2019.Last previous edition approved in 2019 as D8289 19.DOI:10.1520/D8289-20.2For 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.*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.14.2 The str