ASTM_E_1816_-_18.pdf

Designation:E181618Standard Practice forMeasuring thickness by Pulse-Echo ElectromagneticAcoustic Transducer(EMAT)Methods1This standard is issued under the fixed designation E1816;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 practice provides guidelines for measuring thethickness of materials using Electromagnetic Acoustic Trans-ducers(EMAT),a non-contact pulse-echo method,at tempera-tures not to exceed 1200F 650C.1.2 This practice is applicable to any electrically conductiveor ferromagnetic material,or both,in which ultrasonic waveswill propagate at a constant velocity throughout the part,andfrom which back reflections can be obtained and resolved.1.3 UnitsThe values stated in either SI units or inch-pound units are to be regarded separately as standard.Thevalues stated in each system may not be exact equivalents;therefore,each system shall be used independently of the other.Combining values from the two systems may result in noncon-formance with the standard.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:2E114 Practice for Ultrasonic Pulse-Echo Straight-BeamContact TestingE494 Practice for Measuring Ultrasonic Velocity in Materi-alsE543 Specification for Agencies Performing NondestructiveTestingE587 Practice for Ultrasonic Angle-Beam Contact TestingE797 Practice for Measuring Thickness by Manual Ultra-sonic Pulse-Echo Contact MethodE1316 Terminology for Nondestructive ExaminationsE1774 Guide for Electromagnetic Acoustic Transducers(EMATs)2.2 ASNT Standards:3SNT-TC-1A Recommended Practice for Personnel Qualifi-cations and Certification in Nondestructive TestingANSI/ASNT CP-189 Standard for Qualification and Certifi-cation of Nondestructive Testing Personnel2.3 Aerospace Industries Association Standard:NAS 410 Certification and Qualification of NondestructiveTest Personnel42.4 International Standards Organization(ISO):5ISO 9712 Qualification and Certification of NDT Personnel3.Terminology3.1 Definitions:Related terminology is defined in Terminol-ogy E1316.3.2 Definitions of Terms Specific to This Standard:3.2.1 bulk wavean ultrasonic wave,either longitudinal orshear horizontal mode,used in nondestructive testing tointerrogate the volume of a material.3.2.2 butterfly(double elongated racetrack)coilan EMATcoil consisting of two coils wound on an elongated racetrackshape,placed side by side,and connected so the current on theconductors in the middle section flows in only one direction.3.2.3 electromagnetic acoustic transducer(EMAT)anelectromagnetic device for converting electrical energy intoacoustical energy in the presence of a magnetic field.1This practice is under the jurisdiction of ASTM Committee E07 on Nonde-structive Testing and is the direct responsibility of Subcommittee E07.06 onUltrasonic Method.Current edition approved July 1,2018.Published July 2018.Originally approvedin 1996.Last previous edition approved in 2012 as E1816-12.DOI:10.1520/E1816-18.2For 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.3Available fromAmerican Society for Nondestructive Testing(ASNT),P.O.Box28518,1711 Arlingate Ln.,Columbus,OH 43228-0518,http:/www.asnt.org.4Available from Aerospace Industries Association of America,Inc.(AIA),1000Wilson Blvd.,Suite 1700,Arlington,VA22209-3928,http:/www.aia-aerospace.org.5Available from International Organization for Standardization(ISO),ISOCentral Secretariat,BIBC II,Chemin de Blandonnet 8,CP 401,1214 Vernier,Geneva,Switzerland,http:/www.iso.org.*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.1 3.2.4 Lorentz forcesforce