NondestructiveExaminations1 StandardTerminologyfor
This standard is ssed under the fixed designstion E1316; the number immediably folowing the designation indicates the year of original adoption ot in the case of revisin the year of last revision. A number in parentheses indicates the year of last reapproval. A supersctipt psiln () indicates an ditrial chnge sine the last revisin or reappl.
Acoustic Emission (AE) Terms Common NDT TermsElectromagnetic Testing (ET) Terms Gamma- and X-Radiologic Testing (RT) TermsLeak Tesing (LT) Terms Liquid Penetrant Testing (PT) TemsNeutron Rsdiologic Testing (NRT) Terms Magnetic Particle Testing (MT) Terms Utrasonic Testing (UT) Termsse (1H) Buse oueoH eogd Infrared Teting (IRT) Terms (1) S (m
1.Scope
ponent or an ultrasonic measurement of velocity). Additionally the term test should be used when referring to theNDT method that is Radiologic Testing (RT) Ultrasonic Testing (UT) and so forth. (Example: Radiologic Testing (RT)is often used to examine material to detect internal disconti- nuities.)
1.1 This standard defines the terminology used in thestandards prepared by the E07 Committee on Nondestructiveacoustic emission electromagnetic testing. gamma- and Testing. These nondestructive testing (NDT) methods include:X-radiology leak testing liquid penetrant testing magnetic particle testing neutron radiology and gauging ulrasonictesting and other technical methods.
Nor 1The following sentences clarify this policy and illustrate its
use: (a) Nondestructive testing methods are used extensively for the exami-nation or inspection of materials and ponents. (b) The E07 Committee on Nondestructive Testing has prepared manydocuments to promote uniform usage of the nondestructive testing methods that are applied to examine or inspect materials and ponents.internal discontinuities. (c) Radiologic Testing (RT) is often used to inspect material to detectVisual Testing (VT) are often used to examine the surface of a ponent. (d) Magnetic Particle Testing (MT) Liquid Penetrant Testing (PT) andtest a pressure cootaining ponent to detee laks. (e) The Bubble Leak Testing (BLT) method is sometimes used to leakmaterials will describe several methods but a practice will focus on a () A guide for Nondestructive Testing of additively manufactured
1.2 Commite E07 recognizes that the terms examination testing and inspection are monly used as synonyms innondestructive testing. For uniformity and consistency in E07 nondestructive testing standards Commitee E07 encouragesthe use of the terms examination or inspection and their derivatives when describing the application of nondestructivetest methods. In a specific standard either examination orinspection shall be used consistently throughout the document. Similarly E07 encourages the use of the term test and itsnondestructive testing method. There are however appropriate derivatives when referring to the body of knowledge of aexceptions when the term test and its derivatives may be usedto describe the application of a nondestructive test such as measurements which produce a numeric result (for example when using the leak testing method to perform a leak test on a
single inspection method.
1.3 Section A defines terms that are mon to multipleNDT methods whereas the subsequent sections define terms pertaining to specific NDT methods.
1.4 As shown on the chart below when a nondestructivetion is subject to interpretation as false nonrelevant or examination or inspection produces an indication the indica-relevant. If it has been interpreted as relevant the necessary subsequent evaluation will result in the decision to accept orreject the material. With the exception of accept and reject which retain the meaning found in most dictionaries all the
E1316-23
E94 Guide for Radiographic Examination Using IndustrialRadiographic FilmE1106 Test Method for Primary Calibration of Acoustic Emission SensorsE1781 Practice for Secondary Calibration of Acoustic Emis- sion Sensors
words used in the chart are defined in Section A.
NorE 2This standard defines the terminology used in the standandsprepared by Commitee E07 oo Nondestuctive Tesing and published in the Aummal Book of AS7M Stamdands Volumes 03.03 and 03.04.
3. Significance and Use
3.1 The terms found in this standard are intended to be useduniformly and consistently in all nondestructive testing stan- dards. The purpose of this standard is to promote a clearunderstanding and interpretation of the NDT standards inwhich they are used.
1.5 This intermational standord was developed in accor-dance with internationally recognized principles on standard- ization established in the Decision on Principles for theDevelopement of Intermational Standards Guides and Re- mendarions issued by the World Trade Organizarion TechnicalBarriers to Trade (TBT) Committee.
4. Terminology
-qeqde u poueu s uoos qoe ss ou dn uyoq 4.1 DefinirionsThe definitions provided below have been cal order.
2. Referenced Documents
2.1 ASTM Srondards:2
2 For referenced ASTM standards visit the ASTM website .astmorg. orSundands volume infoemution refer to the standard’s Doxcument Summary poge on contact ASTM Customer Service at service astmorg For Anml Book ef ASTMthe ASTM website.
Section A: Common NDT Terms
The terms defined in Section A are the direct responsibility of Submittee E07.92 Editorial Review.
acceptable quality level nthe maximum percent defective or the maximum number of units defective per hundred unitssatisfactory as a process average. that for the purpose of sampling test can be considered
tion of NDT image data and associated metadata in a storage and transmision protocol that defines the organiza-standard electronic format.
sally aptd mdical standard DICOM which facilitas the interp DiscussioxDICONDE is based on and inherits from the univer-erability of imaging equipment through data storage and network munication protocols.
calibration instrument vthe parison of an instrumentwith or the adjustment of an instrument to a knownreference(s) often traceable to the National Institute of Standards and Technology (NIST). (See alsostandardization instrument.)
discontinuity a lack of continuity or cohesion; an inten-tional or unintentional interruption in the physical structure or configuration of a material or ponent.
cognizant engineering organization nthe pany gov- ernment agency or other authority responsible for the design or end use of the material or ponent for which nonde- structive testing is required.
evaluation determination of whether a relevant indication is cause to accept or to reject a material or ponent.
examination n-a procedure for determining a property (orproperties or other conditions or characteristics of a material or ponent by direct or indirect means.
ing organization could include personnel from engineering material DiscussiovIn addition to design personnel the cognizant engineer-assurance and others as appropriate. and peocess engineering stres analysis nondestructive testing quality
DiscussioxExamples include utilization of X-rays or ulrasonicmeg (moen q no famp) uusp jo asdmd aq o sm content density or (for ultrasound) modulus; or detection of flaws byinduction of eddy currents observing thermal behavior AE response or utilization of magnetic particles or liquid penetrants.
defect none or more flaws whose aggregate size shape.orientation location or properties do not meet specified acceptance criteria and are rejectable.
false indication an NDT indication that is interpreted to be caused by a condition other than a discontinuity or imper-fection.
Digital Imaging and Communication for NondestructiveEvaluation (DICONDE) n-a vendor-neutral digital data
flaw nan imperfection or discontinuity that may be detect-able by nondestructive testing and is not necessarily reject-able.
flaw characterization the process of quantifying the size shape orientation location growth or other properties of aflaw based on NDT response.
imperfection n-a departure of a quality characteristic from its intended condition.
indication the response or evidence from a nondestructiveexamination.
q on moesauda q pousap st uoeopu uv-noessnoirelevant non-relevant or false.
inspection see examination.
interpretation the determination of whether indications are relevant or nonrelevant.
interpretation nthe determination of whether indicationsare relevant nonrelevant or false.
Nondestractive Evafuation see Nondestruetive Testing.Nondestructive Examinotion see Nondestructive Testing.Nondestructive Inspection see Nondestructive Testing. Nondestructive Testing (NDT) the development and ap-serviceability in order to detect locate measure and evaluate
plication of technical methods to examine materials orponents in ways that do not impair future usefulness and
acoustic emission (AE) nthe class of phenomena wherebytransient stress/displacement waves are generated by the rapid release of energy from localized sources within amaterial or the transient waves so generated.
use. Other terms that have been used in AE literature include: (7) stress DscussoAcoustic emissioe is the remnded tem for gcncralwave emission (2) microseismic activity and (3) emission or acoustic emission with other qualifying modifiers.
acoustic emission channel nsee channel acoustic emission.
acoustic emission cournr (enission coumz) (N) n-see count acoustic emission.
acoustic emission count rafe nsee count rate acoustieemission (emission rate or count rate) (N).
acoustic emission even nsee event acoustie emission.
acoustic emission event energy see energy acoustic event.acoustic emission mechanism or acoustic emission source mechanism na dynamic process or bination of pro-cesses occurring within a material generating acoustic emission events. AE source mechanisms can be subdividedinto several categories: material and mechanical macro-repuos pue reud ordoosousu pue odoos
Discussiov-Examples of macroscopic material AE source mecha-tion development and fracture of inclusions. Friction and impacts are nisms in metals are incremental crack advancements plastic defoema-examples of mechanical AE. A crack advancement can be considered a
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Section B: Acoustic Emission (AE) Terms
flaws; to assess integrity properties and position; and to
measure geometrical characteristics.nonrelevant indication an NDT indication that is caused by a condition or type of discontinuity that is not rejectable.False indications are non-relevanLreference standard n-a material or object for which all relevant chemical and physical characteristics are known andmeasurable used as a parison for or standardization of equipment or instruments used for nondestructive testing. (See also standardization instrument.)relevant indication nan NDT indication that is caused by a condition or type of discontinuity that requires evaluation.standard (1) a physical reference used as a basis forestablished by authority custom or agreement to serve as a parison or calibration; (2) a concept that has beenlishment of a practice or procedure. model or rule in the measurement of quality or the estab-standardization instrument the adjustment of an NDTor establish a known and reproducible response. (This is instrument using an appropriate reference standard to obtainusually done prior to an examination but can be carried outanytime there is concern about the examination or instru- ment response.) (See also calibration instrument.)
test nsee preferred terms examination or inspection.
primary AE mechanism while a resulting crack surface friction can be
considered as a secondary AE mechanism.acoustic emission signal pirade nsee signal amplitude coustic emission sensor nsee sensor acoustie emission.acousric emission signal (emission signal) nsee signal acoustic emission.acousric emission signgfare (signature) nsee signature acoustic emission.acoustic emission.acousric emission transducer nsee sensor acoustic emis- sion.acoustic emission waveguide n-see waveguide acoustie emission.acousto-ultrasonies (AU) -a nondestructive examinationmethod that uses induced stress waves to detect and assess diffuse defect states damage conditions and variations ofmechanical properties of a test structure. The AU method sesodsewith ultrasonic materials characterization techniques.active source n-one which exhibits increasing cumulative AE activity with increasing or constant stimulus.simulated sources in bination with puted location.
adaptive location nsource location by iterative use of
AE activity nthe presence of acoustic emission during a test.
AE amplirude n-see dBAE
count rate acoustic emission (emission rate or count rate)(N) sthe time rate at which emission counts occur.
AE rms the rectified time averaged AE signal measuredon a linear scale and reported in volts.
count ring-dow sce count acoustie emission the pre-ferred term.
AE signal duration nthe time between AE signal start andAE signal end.
couplant na material used at the structure-to-sensor inter-face to improve the transmission of acoustic energy across the interface during acoustic emission monitoring.
AE signal end nthe recognized termination of an AE signal usually defined as the last crossing of the threshold by thatsignal.
critieally active source one which exhibits an increasingrate of change of cumulative AE activity with increasing orconstant stimulus.
AE signal generator a device which can repeatedly inducea specified transient signal into an AE instrument.
critically intense source none in which the AE sourceintensity consistently increases with increasing stimulus orwith time under constant stimulus.
AE signal rise time the time between AE signal start andthe peak amplitude of that AE signal.
cumulative (acoustic emission) amplitade dissribution F(V) see distribution amplitude cumulative.
AE signal start nthe beginning of an AE signal as recog-nized by the system processor usually defined by anamplitude excursion exceeding threshold.
AE source intensity naverage energy counts or amplitude per hit.
array na group of two or more AE sensors positioned on aThe sources would normally be within the array. structure for the purposes of detecting and locating sources.
(1)
orrival time interval (4t ) nsee interval arrival time
where:
attenuation nthe gradual loss of acoustic emission wave energy as a function of distance through absorption scattering diffraction and geometric spreading.
Ao = 1 μV at the sensor (before amplification) andA = peak voltage of the measured acoustic emission signal (also before amplification).
amplitude or other AE signal parameter per unit distance. DscussovAttenuation can be measured as the decrease in AE
Acoustic Emission Reference Scale:
dBAe Value 0 Voltage at Sensor 1pV60 100 μV 10 μV 1mV100 80 AW 00L 10 mV
average signal level nthe rectified time averaged AElogarithmic signal measured on the AE amplitude logarith- mic scale and reported in dB. units (where O dB. refers to1 μV at the preamplifier input).
broadband or wideband AE sensor nan AE sensor which when calibrated in accordance with Test Method E1106 orPractice E1781 exhibits a displacement or velocity response over several hundred kHz with a coefficient of variation ofthe response in V/m or V/m/s that does not exceed 50 %.
DtsctssoxIn the case of sensors with integral preamplifers the Areference is before internal amplification.
dead time nany interval during data acquisition when theinstrument or system is unable to accept new data for anyreason.
burs eission see emission burst.
channel acoustic emission n-an assembly of a sensor preamplifier or impedance matching transformer filtersconnecting cables and detector or processor.
differential (acoustic eission) threshold crossing distributionf/V) see distribution differential (acoustie emission)threshold crossing.
(FRP) may utilize more than one sensor with associated electronics. DiscussionA channel for examining fiberglass reinforced plasticssusem suanba pue ssus us uarq Channels may be processed independently or in predetermined groups
conrinuous emission nsee emission continuous.
count acoustic emission (emission count) (N) nthe num- ber of times the acoustic emission signal exceeds a presetthreshold during any selected portion of a test.
distribution threshold crossing cumulative (acoustie emis- sion) F (V) nthe number of times the acoustic emission signal exceeds an arbitrary threshold as a function of thethreshold voltage (V).
count event (N) the number obtained by counting cachdiscermed acoustic emission event once.
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energy acoustic emission signal the cnergy contained inan acoustic emission signal which is evaluated as theevaluation threshold a threshold value used for analysis integral of the vol-squared function over time.of the examination data. Data may be recorded with a systemFor analysis purposes dependence of measured data on the examinarion rhreshold lower than the evafuation threshoid.system examination threshold must be taken into consider- ation.event acoustic emission (emission event) an occurrenceacoustic emission. of a local material change or mechanical action resulting inevent coumt (Ne) nsee count event.event coumt rate (Ne) nsee rate event count. examination area (examination region) nthat portion of astructure or test article being examined using acoustic emission technology.Felicity effeet the presence of detectable acoustic emissionbelow those previously applied. at a fixed predetermined sensitivity level at stress levelsFelicity ratio nthe ratio of the stress at which acousticemission is detected to the previously applied maximum stress.was used for the previous loading or examination. DiscussioxThe fixed sensitivity level will usually be the same asfirst hit location a zone location method defined by whicha channel among a group of channels first detects the signal.floating threshold nany threshold with amplitude estab- lished by a time average measure of the input signal.hit n-the detection and measurement of an AE signal on a channel.instrumentation dead time /see dead time instrumenta-intense source -one in which the AE source intensity of an tion.active source consistently exceeds by a specified amount the average AE source intensity of active sources.
distribution differential (acoustic emission) amplitude f(V) nthe number of acoustic emission events with signalamplitudes between amplitudes of V and V V as a function of the amplitude V. f( V) is the absolute value of thederivative of the cumulative amplitude distribution F(V).
distribution differential (acoustic emission) threshold crossing f;(V) nthe number of times the acoustic emissionsignal waveform has a peak between thresholds V and V V as a function of the threshold V. f(V) is the absolute value of the derivative of the cumulative threshold crossing distribution F (V).
distribution logarithmic (acoustic emission) amplitudeg(V) nthe number of acoustic emission events with signal amplitudes between V and αV (where α is a constant multiplier) as a function of the amplitude. This is a variant ofrithmically windowed data.
dynamie range nthe difference in decibels between the overload level and the minimum signal level (usually fixed by one or more of the noise levels low-level distortion interference or resolution level) in a system or sensor.
effective velocity nvelocity calculated on the basis of arrival times and propagation distances determined by artificial AEgeneration; used for puted location.
emission burst na qualitative description of an individual emission event resulting in a discrete signal.
signals on a background of continuous emission signal. DiscussiovFig. 1 shows an oscilloscope trace of burst emission
emission continuous a qualitative description of emissionor successive emission events from one or several sources Suddeo s jo nnson e se peuis pouesns e Sunpodor both.
'seu dams suauogp oml e sqeuatis uorss(s DiscussaovFig. 2 and Fig. 3 show oscilloscope traces of continuous
energy acoustic emission event nthe total elastic energyreleased by an emission event.