ASTM_E_2860_-_12.pdf

Designation:E286012Standard Test Method forResidual Stress Measurement by X-Ray Diffraction forBearing Steels1This standard is issued under the fixed designation E2860;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.INTRODUCTIONThe measurement of residual stress using X-ray diffraction(XRD)techniques has gained muchpopularity in the materials testing field over the past half century and has become a mandatory test formany production and prototype bearing components.However,measurement practices have evolvedover this time period.With each evolutionary step,it was discovered that previous assumptions weresometimes erroneous,and as such,results obtained were less reliable than those obtained usingstate-of-the-art XRD techniques.Equipment and procedures used today often reflect different periodsin this evolution;for example,systems that still use the single-and double-exposure techniques as wellas others that use more advanced multiple exposure techniques can all currently be found inwidespread use.Moreover,many assumptions made,such as negligible shear components andnon-oscillatory sin2 distributions,cannot safely be made for bearing materials in which the demandfor measurement accuracy is high.The use of the most current techniques is,therefore,mandatory toachieve not only the most reliable measurement results but also to enable identification and evaluationof potential measurement errors,thus paving the way for future developments.1.Scope1.1 This test method covers a procedure for experimentallydetermining macroscopic residual stress tensor components ofquasi-isotropic bearing steel materials by X-ray diffraction(XRD).1.2 This test method provides a guide for experimentallydetermining stress values,which play a significant role inbearing life.1.3 Examples of how tensor values are used are:1.3.1 Detection of grinding type and abusive grinding;1.3.2 Determination of tool wear in turning operations;1.3.3 Monitoring of carburizing and nitriding residual stresseffects;1.3.4 Monitoring effects of surface treatments such as sandblasting,shot peening,and honing;1.3.5 Tracking of component life and rolling contact fatigueeffects;1.3.6 Failure analysis;1.3.7 Relaxation of residual stress;and1.3.8 Other residual-stress-related issues that potentiallyaffect bearings.1.4 UnitsThe values stated in SI units are to be regardedas standard.No other units of measurement are included in thisstandard.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:2E6 Terminology Relating to Methods of Mechanical TestingE7 Terminology Relating to MetallographyE915 Test Method for Verifying the Alignment of X-RayDiffraction Instrumentation for Residual Stress Measure-mentE1426 Test Method for Determining the Effective ElasticParameter for X-Ray Diffraction Measurements of Re-sidual Stress1This test method is under the jurisdiction of ASTM Committee E28 onMechanical Testing and is the direct responsibility of Subcommittee E28.13 onResidual Stress Measurement.Current edition approved April 1,2012.Published May 2012.DOI:10.1520/E286012.2For 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.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 2.2 ANSI Standards:3N43.2 Radiation Safety for X-ray Diffraction and Fluores-cence Analysis EquipmentN43.3 For General Radiation SafetyInstallations UsingNon-Medical X-Ray and Sealed Gamma-Ray Sources,Energies Up to 10 MeV3.Terminology3.1 DefinitionsMany of the terms used in this test methodare defined in Terminologies E6 and E7.3.2 Definitions of Terms Specific to This Standard:3.2.1 interplanar spacing,nperpendicular distance be-tween adjacent parallel atomic planes.3.2.2 macrostress,naverage stress acting over a region ofthe test specimen containing many gains/crystals/coherentdomains.3.3 Abbreviations:3.3.1 ALARAAs low as reasonably achievable3.3.2 FWHMFull width half maximum3.3.3 LPALorentz-polarization-absorption3.3.4 MSDSMaterial safety data sheet3.3.5 XECX-ray elastic constant3.3.6 XRDX-ray diffraction3.4 Symbols:12S2hkl=X-ray elastic constant of quasi-isotropic materialequal to11Eeff$hkl%L=Linear thermal expansion coefficient=Angle between the incident beam and 33or surfacenormal on the 3311plane=Angle between the+90direction and the normal to thediffracting pla