1、Designation:E168103(Reapproved 2013)Standard Test Method forDetermining Threshold Stress Intensity Factor forEnvironment-Assisted Cracking of Metallic Materials1This standard is issued under the fixed designation E1681;the number immediately following the designation indicates the year oforiginal ad
2、option 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.Scope1.1 This test method covers the determination of theenvironment-assisted cracking
3、 threshold stress intensity factorparameters,KIEACand KEAC,for metallic materials fromconstant-force testing of fatigue precracked beam or compactfracture specimens and from constant-displacement testing offatigue precracked bolt-load compact fracture specimens.1.2 This test method is applicable to
4、environment-assistedcracking in aqueous or other aggressive environments.1.3 Materials that can be tested by this test method are notlimited by thickness or by strength as long as specimens are ofsufficient thickness and planar size to meet the size require-ments of this test method.1.4 A range of s
5、pecimen sizes with proportional planardimensions is provided,but size may be variable and adjustedfor yield strength and applied force.Specimen thickness is avariable independent of planar size.1.5 Specimen configurations other than those contained inthis test method may be used,provided that well-e
6、stablishedstress intensity calibrations are available and that specimendimensions are of sufficient size to meet the size requirementsof this test method during testing.1.6 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of t
7、he 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:2D1141 Practice for the Preparation of Substitute OceanWaterE8/E8M Test Methods for Tension Testing of Metal
8、lic Ma-terialsE399 Test Method for Linear-Elastic Plane-Strain FractureToughness KIcof Metallic MaterialsE647 Test Method for Measurement of Fatigue CrackGrowth RatesE1823 Terminology Relating to Fatigue and Fracture TestingG1 Practice for Preparing,Cleaning,and Evaluating Corro-sion Test SpecimensG
9、5 Reference Test Method for Making PotentiodynamicAnodic Polarization MeasurementsG15 Terminology Relating to Corrosion and Corrosion Test-ing(Withdrawn 2010)33.Terminology3.1 Definitions:3.1.1 For definitions of terms relating to fracture testingused in this test method,refer to Terminology E1823.3
10、.1.2 For definitions of terms relating to corrosion testingused in this test method,refer to Terminology G15.3.1.3 stress-corrosion cracking(SCC)a cracking processthat requires the simultaneous action of a corrodent andsustained tensile stress.3.1.4 stress intensity factor threshold for plane strain
11、environment-assisted cracking(KIEACFL3/2)the highestvalue of the stress intensity factor(K)at which crack growth isnot observed for a specified combination of material andenvironment and where the specimen size is sufficient to meetrequirements for plane strain as described in Test MethodE399.3.1.5
12、stress intensity factor threshold for environment-assisted cracking(KEACFL3/2)the highest value of thestress intensity factor(K)at which crack growth is notobserved for a specified combination of material and environ-ment and where the measured value may depend on specimenthickness.3.1.6 physical cr
13、ack size(apL)the distance from a ref-erence plane to the observed crack front.This distance may1This test method is under the jurisdiction of ASTM Committee E08 on Fatigueand Fracture and is the direct responsibility of Subcommittee E08.06 on CrackGrowth Behavior.Current edition approved Oct.15,2013
14、.Published March 2014.Originallyapproved in 1995.Last previous edition approved in 2008 as E1681-03(2008)2.DOI:10.1520/E1681-03R14.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information
15、,refer to the standards Document Summary page onthe ASTM website.3The last approved version of this historical standard is referenced onwww.astm.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 represent an average of several measureme
16、nts along the crackfront.The reference plane depends on the specimen form,andit is normally taken to be either the boundary or a planecontaining either the loadline or the centerline of a specimen orplate.The reference plane is defined prior to specimen defor-mation.3.1.7 original crack size(aoL)the physical crack size atthe start of testing.3.1.8 original uncracked ligament(boL)distance fromthe original crack front to the back edge of the specimen(bo=W ao).3.1.9 specimen thickness(BL)the side-t
