ASTM_E_139_-_11.pdf

Designation:E13911Standard Test Methods forConducting Creep,Creep-Rupture,and Stress-RuptureTests of Metallic Materials1This standard is issued under the fixed designation E139;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.This standard has been approved for use by agencies of the U.S.Department of Defense.1.Scope*1.1 These test methods cover the determination of theamount of deformation as a function of time(creep test)andthe measurement of the time for fracture to occur whensufficient force is present(rupture test)for materials whenunder constant tensile forces at constant temperature.It alsoincludes the essential requirements for testing equipment.Forinformation of assistance in determining the desirable numberand duration of tests,reference should be made to the productspecification.1.2 These test methods list the information which should beincluded in reports of tests.The intention is to ensure that alluseful and readily available information is transmitted tointerested parties.Reports receive special attention for thefollowing reasons:(1)results from different,recognized pro-cedures vary significantly;therefore,identification of methodsused is important;(2)later studies to establish importantvariables are often hampered by the lack of detailed informa-tion in published reports;(3)the nature of prolonged tests oftenmakes retest impractical,and at the same time makes it difficultto remain within the recommended variations of some con-trolled variables.A detailed report permits transmittal of testresults without implying a degree of control which was notachieved.1.3 Tests on notched specimens are not included.These testsare addressed in Practice E292.1.4 Tests under conditions of short times are not included.These test methods are addressed in Test Methods E21.1.5 The values stated in inch-pound units are to be regardedas standard.The values given in parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.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:2E4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE8 Test Methods for Tension Testing of Metallic MaterialsE21 Test Methods for Elevated Temperature Tension Tests ofMetallic MaterialsE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE74 Practice of Calibration of Force-Measuring Instrumentsfor Verifying the Force Indication of Testing MachinesE83 Practice for Verification and Classification of Exten-someter SystemsE177 Practice for Use of the Terms Precision and Bias inASTM Test MethodsE220 Test Method for Calibration of Thermocouples ByComparison TechniquesE292 Test Methods for Conducting Time-for-Rupture NotchTension Tests of MaterialsE633 Guide for Use of Thermocouples in Creep and Stress-Rupture Testing to 1800F(1000C)in AirE1012 Practice for Verification of Testing Frame and Speci-men Alignment Under Tensile and Compressive AxialForce Application3.Terminology3.1 DefinitionsThe definitions of terms relating to creeptesting,which appear in Section E of Terminology E6 shallapply to the terms used in this practice.For the purpose of thispractice only,some of the more general terms are used with therestricted meanings given below.3.2 Definitions of Terms Specific to This Standard:1These test methods are under the jurisdiction of the ASTM Committee E28 onMechanical TestingCurrent edition approved June 1,2011.Published August 2011.Originallyapproved in 1958.Last previous edition approved in 2006 as E139 06.DOI:10.1520/E0139-11.2For 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 States1 3.2.1 axial strainthe average of the strain measured onopposite sides and equally distant from the specimen axis.3.2.2 bending strainthe difference between the strain atthe surface of the specimen and the axial strain.In general itvaries from point to point around and along the reduced sectionof the specimen.3.2.2.1 maximum bending strainmeasured at a positionalong the length of the reduced section of a straight unnotchedspecimen.3.2.3 creepthe time-