1、Designation: E1004 09E1004 17Standard Test Method forDetermining Electrical Conductivity Using theElectromagnetic (Eddy-Current) (Eddy Current) Method 1This standard is issued under the fixed designation E1004; the number immediately following the designation indicates the year oforiginal adoption o
2、r, 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.1. S
3、cope*1.1 This test method covers a procedure for determining the electrical conductivity of nonmagnetic metals using theelectromagnetic (eddy-current) (eddy current) method. The procedure has been written primarily for use with commerciallyavailable direct reading electrical conductivity instruments
4、. General purpose eddy-current eddy current instruments may also beused for electrical conductivity measurements but will not be addressed in this test method.1.2 This test method is applicable to metals that have either a flat or slightly curved surface and includes metals with or withouta thin non
5、conductive coating.1.3 Eddy-current Eddy current determinations of electrical conductivity may be used in the sorting of metals with respect tovariables such as type of alloy, aging, cold deformation, heat treatment, effects associated with non-uniform heating or overheating,and effects of corrosion
6、. The usefulness of the examinations of these properties is dependent on the amount of electricalconductivity change caused by a change in the specific variable.1.4 Electrical conductivity, when evaluated with eddy-current eddy current instruments, is usually expressed as a percentage ofthe conducti
7、vity of the International Annealed Copper Standard (IACS). (% IACS) or Siemens/meter (S/m). The conductivity ofthe Annealed Copper Standard is defined to be 0.58 100.58 108 S/m (100 % IACS) (100 % IACS) at 20C.1.5 The values stated in SI units are regarded as standard.1.6 This standard does not purp
8、ort to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatorylimitations prior to use.1.7 This international standard was developed in
9、 accordance with internationally recognized principles on standardizationestablished in the Decision on Principles for the Development of International Standards, Guides and Recommendations issuedby the World Trade Organization Technical Barriers to Trade (TBT) Committee.2. Referenced Documents2.1 A
10、STM Standards:2B193 Test Method for Resistivity of Electrical Conductor MaterialsE10 Test Method for Brinell Hardness of Metallic MaterialsE18 Test Methods for Rockwell Hardness of Metallic MaterialsE105 Practice for Probability Sampling of MaterialsE122 Practice for Calculating Sample Size to Estim
11、ate, With Specified Precision, the Average for a Characteristic of a Lot orProcessE140 Hardness Conversion Tables for Metals Relationship Among Brinell Hardness, Vickers Hardness, Rockwell Hardness,Superficial Hardness, Knoop Hardness, Scleroscope Hardness, and Leeb HardnessE543 Specification for Ag
12、encies Performing Nondestructive TestingE1251 Test Method for Analysis of Aluminum and Aluminum Alloys by Spark Atomic Emission Spectrometry1 This test method is under the jurisdiction ofASTM Committee E07 on NondestructiveTesting and is the direct responsibility of Subcommittee E07.07 on Electromag
13、neticMethod.Current edition approved May 15, 2009June 1, 2017. Published June 2009June 2017. Originally approved in 1991. Last previous edition approved in 20022009 asE1004 - 02.E1004 - 09. DOI: 10.1520/E1004-09.10.1520/E1004-17.2 For referencedASTM standards, visit theASTM website, www.astm.org, or
14、 contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes hav
15、e been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official doc
16、ument.*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 States1E1316 Terminology for Nondestructive ExaminationsE2371 Test Method for Analysis of Titanium and Titanium Alloys by
17、Direct Current Plasma and Inductively Coupled PlasmaAtomic Emission Spectrometry (Performance-Based Test Methodology)2.2 ASNT Documents:3Recommended Practice SNT-TC-1A Recommended Practice for Personnel Qualification and Certification In NondestructiveTestingANSI/ASNT-CP-189 Standard for Qualificati
18、on and Certification of NDT Nondestructive Testing Personnel2.3 AIA Document:4NAS410 Certification and Qualification of Nondestructive Testing Personnel2.4 ISO Standard:5ISO 9712 Non-Destructive Testing: Qualification and Certification of NDT Personnel3. Terminology3.1 DefinitionsDefinitions of term
19、s relating to eddy-current eddy current examination are given in Terminology E1316.3.2 Definitions of Terms Specific to This Standard:3.2.1 temperature coeffcientthe fractional or percentage change in electrical conductivity per degree Celsius change intemperature.4. Significance and Use4.1 Absolute
20、 probe coil methods, when used in conjunction with reference standards of known value, provide a means fordetermining the electrical conductivity of nonmagnetic materials.4.2 Electrical conductivity of a sample sample, when used in conjunction with another method listed and compared to referencechar
21、ts, can be used as a means of determining: determining: (1) type ) type of metal or alloy, (2) type of heat treatment (foraluminum this evaluation should be used in conjunction with a hardness examination), (3) aging of the alloy, (4) effects ofcorrosion, and (5) heat damage.damage, (6) temper, and
22、(7) hardness.5. Limitations5.1 The ability to accomplish the examinations included in 4.2 is dependent on the conductivity change caused by the variableof interest. If the conductivity is a strong function of the variable of interest, these examinations can be very accurate. In somecases, however, c
23、hanges in conductivity due to changes in the variable of interest may be too small to detect. The ability to isolatethe variable of interest from other variables is also important. For example, if the alloy is not known, the heat treatment cannotbe determined from conductivity alone.5.2 The curve re
24、lating temper and conductivity of an aluminum alloy should be known before attempting to interpretconductivity measurements. If electrical conductivity measurements are used to interpret a property that is related to the electricalconductivity, the correlation curve relating the property to the elec
25、trical conductivity should be established for such use. Forexample, knowing alloy and heat treatment, the alloy, conductivity, and hardness; or the conductivity, chemistry, and thermalhistory; or conductivity, chemistry, and tensile strength, the adequacy of the heat treatment can be estimated.6. Ba
26、sis of Application6.1 Personnel Qualification:6.1.1 If specified by the contractual agreement, personnel performing examinations to this test method shall be qualified inaccordance with a nationally or internationally recognized NDT personnel qualification standard such as ANSI/ASNT-CP-189,SNT-TC-1A
27、, NAS-410, ISO 9712 , or a similar document and certified by the employer or certifying agency, as applicable. Thepractice of the standard used and its applicable revision shall be specified in the contractual agreement between the using parties.NOTE 1Note that NAS-410 does not require personnel cer
28、tification when using direct read instruments6.1.2 Qualification and certification for personnel may be reduced when the following conditions are met:6.1.2.1 The examination will be limited to operating equipment, which displays the results in percent IACS.6.1.2.2 A specific procedure is used that i
29、s approved by a certified Level III in accordance with 6.1.1.6.1.2.3 Documentation of training and examination is performed to ensure that personnel are qualified. Qualified personnel arethose who have demonstrated, by passing written and practical proficiency tests, that they possess the skills and
30、 job knowledgenecessary to ensure acceptable workmanship.3 Available from American Society for Nondestructive Testing (ASNT), P.O. Box 28518, 1711 Arlingate Ln., Columbus, OH 43228-0518, http:/www.asnt.org.4 Available from Aerospace Industries Association of America, Inc. (AIA), 1000 Wilson Blvd., S
31、uite 1700, Arlington, VA 22209-3928, http:/www.aia-aerospace.org.5 Available from International Organization for Standardization (ISO), ISO Central Secretariat, BIBC II, Chemin de Blandonnet 8, CP 401, 1214 Vernier, Geneva,Switzerland, http:/www.iso.org.E1004 1726.2 Qualification of Nondestructive T
32、esting AgenciesIf specified in the contractual agreement, NDT agencies shall be qualifiedand evaluated as described in Practice E543. The applicable edition of Practice E543 shall be specified in the contractualagreement.6.3 The following additional items are subject to contractual agreement between
33、 the parties using or referencing this testmethod.6.3.1 Timing of Examination6.3.2 Extent of Examination6.3.3 Reporting Criteria/Acceptance Criteria6.3.4 Reexamination of Repaired/Reworked Items7. Variables Influencing Accuracy7.1 Consider the influence of the following variables to ensure an accura
34、te evaluation of electrical conductivity.7.1.1 TemperatureThe instrument, probe, reference standards, and parts being examined shall be stabilized at ambienttemperature prior to conductivity evaluation. When possible, examinations should be performed at room temperature (typically 686 15F).20 C).7.1
35、.2 Probe Coil to Metal CouplingVariations in the separation between the probe coil and the surface of the sample (lift-off)can cause large changes in the instrument output signal. Instruments vary widely in sensitivity due to lift-off, and some haveadjustments for minimizing it. Standardize the inst
36、rument with values at least as large as the known lift-off. Surface curvature mayalso affect the coupling. (Consult the manufacturers manual for limitations on lift-off and surface curvature).7.1.3 Edge EffectTests should not be performed within two coil diameters of any discontinuity, such as an ed
37、ge, hole, or notchunless coil manufacturers instructions allow. Consult manufacturers instructions to determine equipment limitations forinspection adjacent to any discontinuity. If no information regarding probe use restrictions or limitations adjacent to suchdiscontinuities exist, examinations sho
38、uld not be performed within two coil diameters of any discontinuity.7.1.4 Uniformity of SampleVariations in material properties are common and can be quite large. Discontinuities orinhomogeneities in the metal near the position of the probe coil will change the value of the measured conductivity.NOT
39、E 2Similar materials from various manufacturing methods (extrusion, forging, casting, rolling, machined vs. unmachined) may exhibit significantconductivity variation between processes. Eddy current conductivity meters can be affected by detecting differences in material grain structure, alloyuniform
40、ity, and internal stresses so care must be taken as this can influence accuracy.7.1.5 Surface ConditionsSurface treatments and roughness can affect the measured conductivity value of a material. Claddingalso has Conductive coatings such as cladding will have a pronounced effect on conductivity readi
41、ngs as compared to the basemetal values. Procedures for determining the electrical conductivity of clad materials are not addressed in this test method. Thesample surface should be clean and free of grease.7.1.6 Instrument StabilityInstrument drift, noise, and nonlinearities can cause inaccuracies i
42、n the measurement.7.1.7 Nonunique Conductivity ValuesIt should be noted that two different alloys can have the same conductivity. Thus, insome cases, a measurement of conductivity may not uniquely characterize an alloy. Overheated parts and some heat-treatedaluminum alloys are examples of materials
43、that may have identical conductivity values for different heat treatments or tempers.It is recommended, if chemistry and thermal history are unknown, that an indentation hardness test (such as Rockwell, Vickers,Brinell), accompanied by a test to determine chemistry such as Laser-Induced Breakdown Sp
44、ectroscopy (LIBS), X-RayFluorescence (XRF), Atomic Emission Spectrometry (AES), Inductively Coupled Plasma (ICP), or Glow Discharge MassSpectrometry (GDMS) chemical spot test or other laboratory analysis be used to identify an unknown material. Refer to TestMethods E10, E18, E1251, and E2371, and St
45、andard Conversion Tables E140, for more information on methods for determiningchemistry.7.1.8 Sample ThicknessEddy-current Eddy current density decreases exponentially with depth (that is, distance from the metalsurface). The depth at which the density is approximately 37 % (1/e) of its value at the
46、 surface is called the standard depth ofpenetration . Calculate the standard depth of penetration for nonmagnetic materials using one of the following formulas:5503.3=fm!,51/ (1)5503.3=fm!, in Sm (1)5 K=1/!frcm!,K.50,r 51 (2)5 50.3=rf1/mm!, in cm,r 51 (2)5 1=pifm!, 5or,o 54pi31027,r 51 (3)E1004 1735
47、 1=pifm!, in Sm, 5or,o 54pi31027Hm,r 51 (3)5 660=fmm! , in %IACS (4)where: = electrical conductivity of the sample in S/m, = electrical conductivity of the sample, = electrical resistivity in m,and = electrical resistivity, andf = examination frequency in Hz.These formulas are for nonmagnetic materi
48、als when the relative permeability, relr=1. If the thickness of the sample and thereference standards is at least 2.6, the effect of thickness is negligible. Smaller depths of penetration (higher frequencies) may bedesirable for measuring surface effects. The eddy-current eddy current density decrea
49、se with depth is also affected by the coildiameter. The change due to coil diameter variation is not considered in the above equation. Consult the instrument manufacturerif penetration depth appears to be a source of error in the measurement.NOTE 3When testing thin materials, stacking of the test parts may be acceptable. Similar material, preferably from the same batch or sheet, may beused to back the material being interrogated, thereby increasing the effective thickness. Stacked materials mus
