ASTM_B_645_-_10_2015.pdf

Designation:B64510(Reapproved 2015)Standard Practice forLinear-Elastic PlaneStrain Fracture Toughness Testing ofAluminum Alloys1This standard is issued under the fixed designation B645;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.INTRODUCTIONLinear-elastic plane-strain fracture toughness testing of aluminum alloys is performed essentially inaccordance with Test Method E399.However,there is a need,in the application of Test Method E399for quality assurance testing,to deal with the interpretation of the results for material qualification andrelease in cases where all requirements for valid measurements of plane-strain fracture toughnesscannot be met.It is the purpose of this practice to provide consistent methods of dealing with thosesituations.1.Scope*1.1 This practice is applicable to the fracture toughnesstesting of all aluminum alloys,tempers,and products,espe-cially in cases where the tests are being made to establishwhether or not individual lots meet the requirements ofspecifications and should be released to customers.1.2 Test Method E399 is the basic test method to be used forplane-strain fracture toughness testing of aluminum alloys.Thepurpose of this practice is to provide supplementary informa-tion for plane-strain fracture toughness of aluminum alloys inthree main areas:1.2.1 Specimen sampling,1.2.2 Specimen size selection,and1.2.3 Interpretation of invalid test results.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.3.1 ExceptionCertain inch-pound values given in paren-theses are provided for information only.1.4 This standard is currently written to accommodate onlyC(T)specimens.1.5 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:2B646 Practice for Fracture Toughness Testing of AluminumAlloysE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE399 Test Method for Linear-Elastic Plane-Strain FractureToughness KIcof Metallic MaterialsE561 Test Method forK-R Curve DeterminationE1823 Terminology Relating to Fatigue and Fracture Testing3.Terminology3.1 GeneralTerms,definitions,symbols,and orientationdesignations in Test Method E399 and Terminology E1823 areapplicable herein.3.2 Definitions:The following additional definitions are ap-plicable:3.2.1 invalid plane-strain fracture toughnesstest result,KQ,that does not meet one or more of the validity requirementsin Test Method E399 and,where so characterized,is of novalue in judging the true plain-strain fracture toughness of amaterial but may,under certain conditions,adequately guaran-tee the materials fracture toughness for lot release purposes.1This practice is under the jurisdiction of ASTM Committee B07 on LightMetals and Alloys and is the direct responsibility of Subcommittee B07.05 onTesting.Current edition approved Dec.1,2015.Published December 2015.Originallyapproved in 1978.Last previous edition approved in 2010 as B645 10.DOI:10.1520/B0645-10R15.2For 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 3.2.2 valid plane-strain,fracture toughnesstest resultmeeting all the validity requirements in Test Method E399,thatis,a value of KIc.4.Summary of Practice4.1 This practice supplements Test Method E399 and Prac-tice B646 in three main areas:4.1.1 Specimen sampling,4.1.2 Specimen size selection,and4.1.3 Interpretation of results that fail the validity require-ments in Test Method E399 in one of the following areas inorder to determine if the invalid results are usable for lotrelease:4.1.3.1 Pmax/PQrequirements,4.1.3.2 Specimen size requirements,and4.1.3.3 Fatigue precracking requirements.5.Significance and Use5.1 This practice for plane-strain fracture toughness testingof aluminum alloys may be used as a supplement to TestMethod E399.The application of this practice is primarilyintended for quality assurance and material release in caseswhere valid plane-strain fracture toughness data cannot beobtained per Test Method E399.5.2 It must be understood that the interpretations andguidelines i