ASTM_E_2884_-_13e1.pdf

Designation:E2884131Standard Guide forEddy Current Testing of Electrically Conducting MaterialsUsing Conformable Sensor Arrays1This standard is issued under the fixed designation E2884;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.1NOTESection 2 was corrected editorially in June 2104.1.Scope1.1 This guide covers the use of conformable eddy currentsensor arrays for nondestructive examination of electricallyconducting materials for discontinuities and material quality.The discontinuities include surface breaking and subsurfacecracks and pitting as well as near-surface and hidden-surfacematerial loss.The material quality includes coating thickness,electrical conductivity,magnetic permeability,surface rough-ness and other properties that vary with the electrical conduc-tivity or magnetic permeability.1.2 This guide is intended for use on nonmagnetic andmagnetic metals as well as composite materials with anelectrically conducting component,such as reinforced carbon-carbon composite or polymer matrix composites with carbonfibers.1.3 This guide applies to planar as well as non-planarmaterials with and without insulating coating layers.1.4 UnitsThe values stated in SI units are to be regardedas standard.The values given in parentheses are mathematicalconversions to inch-pound units that are provided for informa-tion only and are not considered standard.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:2E543 Specification for Agencies Performing NondestructiveTestingE1316 Terminology for Nondestructive ExaminationsE2338 Practice for Characterization of Coatings Using Con-formable Eddy-Current Sensors without Coating Refer-ence Standards2.2 ASNT Documents:3SNT-TC-1A Recommended Practice for Personnel Qualifi-cation and Certification in Nondestructive TestingANSI/ASNT-CP-189 Standard for Qualification and Certifi-cation of NDT Personnel2.3 AIA Standard:NAS 410 Certification and Qualification of NondestructiveTesting Personnel42.4 Department of Defense Handbook:MIL-HDBK1823A Nondestructive Evaluation System Re-liability Assessment3.Terminology3.1 DefinitionsFor definitions of terms relating to thisguide refer to Terminology E1316.3.2 Definitions of Terms Specific to This Standard:3.2.1 B-Scana method of data presentation utilizing ahorizontal base line that indicates distance along the surface ofa material and a vertical deflection that represents a measure-ment response for the material being examined.3.2.2 C-Scana method of data presentation which pro-vides measurement responses for the material being examinedin two-dimensions over the surface of the material.3.2.3 conformablerefers to an ability of sensors or sensorarrays to conform to non-planar surfaces without significanteffects on the measurement results,or with effects that arelimited to a quantifiable bound.1This guide is under the jurisdiction of ASTM Committee E07 on Nondestruc-tive Testing and is the direct responsibility of Subcommittee E07.07 on Electro-magnetic Method.Current edition approved June 1,2013.Published June 2013.Originallyapproved in 2013.Last previous edition approved in 2013 as E288413.DOI:10.1520/E2884-13E01.2For 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.(Replacement standard for MIL-STD-410.)Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.2.4 depth of sensitivitydepth to which the sensor re-sponse to features or properties of interest exceeds a noisethreshold.3.2.4.1 DiscussionThe depth of sensitivity is generallysmaller than the depth of penetration since it incorporates acomparison between the signal obtained from a feature as wellas measurement noise,whereas the depth of penetration refersto the decrease in field intensity with distance away from a testcoil.3.2.5 discontinuity-containing reference standarda regionof the material under examination or a material having elec-tromagnetic properties similar to the material under examina-tion for which a discontinuity having known characteristics ispres