1、Designation: E2533 16Standard Guide forNondestructive Testing of Polymer Matrix Composites Usedin Aerospace Applications1This standard is issued under the fixed designation E2533; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、 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. Scope1.1 This guide provides inf
3、ormation to help engineers selectappropriate nondestructive testing (NDT) methods to charac-terize aerospace polymer matrix composites (PMCs). Thisguide does not intend to describe every inspection technology.Rather, emphasis is placed on established NDT methods thathave been developed into consensu
4、s standards and that arecurrently used by industry. Specific practices and test methodsare not described in detail, but are referenced. The referencedNDT practices and test methods have demonstrated utility inquality assurance of PMCs during process design andoptimization, process control, after man
5、ufacture inspection,in-service inspection, and health monitoring.1.2 This guide does not specify accept-reject criteria and isnot intended to be used as a means for approving compositematerials or components for service.1.3 This guide covers the following established NDT meth-ods as applied to PMCs:
6、Acoustic Emission (AE, 7), ComputedTomography (CT, 8), Leak Testing (LT, 9), RadiographicTesting, Computed Radiography, Digital Radiography, andRadioscopy (RT, CR, DR, RTR, 10), Shearography (11), StrainMeasurement (contact methods, 12), Thermography (13), Ul-trasonic Testing (UT, 14), and Visual Te
7、sting (VT, 15).1.4 The value of this guide consists of the narrative descrip-tions of general procedures and significance and use sectionsfor established NDT methods as applied to PMCs. Additionalinformation is provided about the use of currently activestandard documents (an emphasis is placed on ap
8、plicablestandard guides, practices, and test methods of ASTM Com-mittee E07 on Nondestructive Testing), geometry and sizeconsiderations, safety and hazards considerations, and infor-mation about physical reference standards.1.5 To ensure proper use of the referenced standarddocuments, there are reco
9、gnized NDT specialists who arecertified in accordance with industry and company NDTspecifications. It is recommended that a NDT specialist be apart of any composite component design, quality assurance,in-service maintenance or damage examination.1.6 This guide summarizes the application of NDT metho
10、dsto fiber- and fabric-reinforced polymeric matrix composites.The composites of interest are primarily, but not exclusivelylimited to those containing high modulus (greater than 20 GPa(3106psi) fibers. Furthermore, an emphasis is placed oncomposites with continuous (versus discontinuous) fiber rein-
11、forcement.1.7 This guide is applicable to polymeric matrix compositescontaining but not limited to bismaleimide, epoxy, phenolic,poly(amide imide), polybenzimidazole, polyester (thermoset-ting and thermoplastic), poly(ether ether ketone), poly(etherimide), polyimide (thermosetting and thermoplastic)
12、, poly-(phenylene sulfide), or polysulfone matrices; and alumina,aramid, boron, carbon, glass, quartz, or silicon carbide fibers.1.8 The composite materials considered herein include uni-axial laminae, cross-ply laminates, angle-ply laminates, andstructural sandwich constructions. The composite comp
13、onentsmade therefrom include filament-wound pressure vessels,flight control surfaces, and various structural composites.1.9 For current and potential NDT procedures for findingindications of discontinuities in the composite overwrap infilament-wound pressure vessels, also known as compositeoverwrapp
14、ed pressure vessels (COPVs), refer to Guide E2981.1.10 For a summary of the application of destructiveASTMstandard test methods (and other supporting standards) tocontinuous-fiber reinforced PMCs, refer to Guide D4762.1.11 The values stated in SI units are to be regarded as thestandard. The values g
15、iven in parentheses are provided forinformation only.1.12 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
16、of regulatory limitations prior to use.1This guide is under the jurisdiction of ASTM Committee E07 on Nondestruc-tive Testing and is the direct responsibility of Subcommittee E07.10 on SpecializedNDT Methods.Current edition approved July 1, 2016. Published October 2016. Originallyapproved in 2009. L
17、ast previous edition approved as E253309. DOI: 10.1520/E2533-16.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States12. Referenced Documents2.1 ASTM Standards:2C274 Terminology of Structural Sandwich Constructions(Withdrawn 2016)3D3878 Ter
18、minology for Composite MaterialsD4762 Guide for Testing Polymer Matrix Composite Mate-rialsE543 Specification for Agencies Performing NondestructiveTestingE1316 Terminology for Nondestructive ExaminationsE1742 Practice for Radiographic ExaminationE2981 Guide for Nondestructive Testing of the Composi
19、teOverwraps in Filament Wound Pressure Vessels Used inAerospace Applications2.2 ASNT Standard:SNT-TC-1A Recommended Practice for Personnel Qualifi-cation and Certification in Nondestructive Testing42.3 ASTM Adjuncts:Curing Press Straining Block (13 Drawings)53. Terminology3.1 AbbreviationsThe follow
20、ing abbreviations are ad-opted in this guide: Acoustic Emission (AE), ComputedRadiography (CR), Computed Tomography (CT), Digital Ra-diography (DR), Leak Testing (LT), Radiography (RT), Ra-dioscopy (RTR), and Ultrasound (UT).3.2 DefinitionsDefinitions of terms related to NDT ofaerospace composites w
21、hich appear in Terminology E1316 andTerminology D3878 shall apply to the terms used in the guide.3.3 Definitions of Terms Specific to This Standard:3.3.1 aerospaceany component that will be installed on asystem that flies.3.3.2 cognizant engineering organizationthe company,government agency, or othe
22、r authority responsible for thedesign, or end use, of the system or component for which NDTis required. This, in addition to the design personnel, mayinclude personnel from engineering, materials and processengineering, stress analysis, NDT, or quality groups and other,as appropriate.3.3.3 composite
23、 materialsee Terminology D3878.3.3.4 composite componenta finished part containingcomposite material(s) that is in its end use applicationconfiguration, and which has undergone processing,fabrication, and assembly to the extent specified by thedrawing, purchase order, or contract.3.3.5 composite she
24、lla multilayer filament-winding thatcomprises a second shell that reinforces the inner shell. Thecomposite shell consists of continuous fibers, impregnated witha matrix material, wound around the inner shell, and cured inplace. The number of layers, fiber orientation, and compositeshell thickness ma
25、y vary from point-to-point.3.3.6 disbondsee Terminology D3878.3.3.7 filament wound pressure vesselan inner shell over-wrapped with composite layers that form a composite shell.The inner shell or liner may consist of an impervious metallicor nonmetallic material. The vessel may be cylindrical orspher
26、ical and will have at least one penetration with valveattachments for introducing and holding pressurized liquids orgases.3.3.8 in-servicerefers to composite components that havecompleted initial fabrication and are in use (or in storage) fortheir intended function.3.3.9 microcrackinvisible cracks (
27、15) aspect ratios.A digitized cross-sectional CT-density map(tomogram) of the articleunder test. Allows full,three dimensional CT-density maps to beobtained for sufficientlysmall composite parts.Tooling and/or part-handling fixtures may berequired.Leak Testing Any composite materialor component acro
28、sswhich a differentialpressure exists andwhere through-leakageor in-leakage of product,air, water vapor, or othercontaminant over theprojected service life areof concern.Less ambiguous thanliquid penetrant testing;more sensitive than AEor UT.Test equipment costsincrease as the requiredleak test sens
29、itivityincreases.Qualitative indications,for example bubbles, orquantitativemeasurements, forexample, detectordeflections, thatascertain the presenceor location, orconcentration or leakrate of a leaking fluid.Different techniques areavailable forcharacterization of largeleaks (with rates as highas 1
30、0-2Pa m3s-1(10-1std cm3s-1) and smallleaks (rates less than10-5Pa m3s-1(10-4stdcm3s-1).Radiography,Computed Radiography,Radiography with DigitalDetector Arrays,RadioscopyPrimarily detects sub-surface imperfections ordiscontinuities such asporosity sometimes possible fromdigital images aftercalibrati
31、on or withadditional X-rayexposures from differentdirections.Projected area anddensity variation ofsubsurface imperfectionsor discontinuities.Part may need to bemoved to an X-ray lab;Film RT requires filmstorage and disposal ofchemicals which can beexpensive. Digitaltechniques (CR, DDA)are usually f
32、aster.Radiation safety. Inradioscopy, radiationsafety more problematicif a moving source isused, versus movementof part.E2533 164accordance with the referenced documents in this guide, theengineering drawing, specification, purchase order, or contractshall indicate the acceptance criteria.5.3.1 Acce
33、pt/reject criteria shall consist of a listing of theexpected kinds of imperfections and the rejection level foreach.TABLE 2 ContinuedNDT Method Applications Advantages LimitationsWhat Is Seenand Reported?Other ConsiderationsShearography Detects subsurfaceimperfections ordiscontinuities orchanges in
34、modulus orout-of-plane deformation.Well suited for highspeed, automatedinspection in productionenvironments.Subsurface imperfectionor discontinuity must besufficiently large tocause measurablesurface deformationunder load. Surfacecondition, especiallyglossiness, can interferewith accurateshearograph
35、ic detection,thus requiring the use ofsurface dulling agents(exception: thermalshearography).An interference patterncreated by subtracting orsuperimposing images ofthe article under testtaken before and afterloading, thus revealinglocalized strainconcentrations.Additional equipment isrequired to det
36、erminesurface derivative slopechanges, and thus usesthe method as aquantitative tool.Strain Measurement Can be used to measurestatic and dynamictensile and compressivestrain, as well asshearing, Poisson,bending, and torsionalstrains.Relatively inexpensive,and less bulky and betterresolution thanexte
37、nsometers (canachieve an overallaccuracy of better than 0.10% strain).Individual strain gaugescannot be calibrated andare susceptible tounwanted noise andother sources of errorsuch as expansion orcontraction of the strain-gauge element, changein the resistivity, andhysteresis and creepcaused by impe
38、rfectbonding.The output of aresistance measuringcircuit is expressed inmillivolts output per voltinput.Depending on desiredsensitivity, resistance todrift, insensitivity totemperature variations,or stability of installation,a variety of straingauges are available (forexample, semiconductorwafer sens
39、ors, metallicbonded strain gauges,thin-film and diffusedsemiconductor straingauges).Thermography Detects disbonds,delaminations, voids,pits, cracks, inclusions,and occlusions,especially in thin articlesunder test having lowthermal conductivity, lowreflectivity/high emissivitysurfaces, and inmaterial
40、s which dissipateenergy efficiently,Quick observation oflarge surfaces andidentification of regionsthat should be examinedmore carefully.Composites havetemperature limitsbeyond whichirreversible matrix andfiber damage can occur.Imperfection ordiscontinuity detectiondepends on orientationof an imperf
41、ection ordiscontinuity relative tothe direction of heatflow. In thicker materials,only qualitativeindications ofimperfections ordiscontinuities arepossible.The aerial temperaturedistribution is measuredby mapping contours ofequal temperature(isotherms), thus yieldinga heat emission patternrelated to
42、 surface andsubsurface defects.Both contact (requiresapplication of a coating)and noncontact methods(relies on detection ofinfrared blackbodyradiation) are available.Thermography is eitherpassive or active, activethermography can befurther subdivided intopulse or lock-intechniques.Ultrasonic Testing
43、 Detects sub-surfaceimperfections ordiscontinuities. There aretwo primary techniques;pulse echo for one sidedinspections and throughtransmission for twosided inspections.Detects sub-surfaceimperfections ordiscontinuities includingporosity, inclusions, anddelaminations.Requires a relatively flatand s
44、mooth surface.Material type can affectinspectability.Imperfections ordiscontinuities aredirectly recorded onamplitude images.Possible fluidentrapment; possiblefluid absorption intoporous materials such ascomposites. Numeroustechniques availableincluding longitudinal,shear or surface waves.Attenuatio
45、n can becomparatively high inPMCs compared tometallic articles.Visual Testing Detects disruptions onsurfaces being viewed.Low cost. Detect surfaceimperfections ordiscontinuities includingdelaminations, fiberbreakage, impactdamage.Requires direct line ofsight.Imperfections ordiscontinuities aredirect
46、ly recorded oninspectiondocumentationsometimes photographs.Can find imperfections ordiscontinuities on insidediameters if a centralconductor can beinserted and satisfactoryelectrical contact made.E2533 1655.3.2 The classification of the articles under test into zonesfor various accept/reject criteri
47、a shall be determined fromcontractual documents.5.3.3 Rejection of Composite ArticlesIf the type, size, orquantities of defects are found to be outside the allowablelimits specified by the drawing, purchase order, or contract, thecomposite article shall be separated from acceptable articles,appropri
48、ately identified as discrepant, and submitted for mate-rial review by the cognizant engineering organization, anddispositioned as (1) acceptable as is, (2) subject to furtherrework or repair to make the materials or componentacceptable, or (3) scrapped when required by contractualdocuments.5.3.4 Acc
49、eptance criteria and interpretation of result shallbe defined in requirements documents prior to performing theexamination. Advance agreement should be reached betweenthe purchaser and supplier regarding the interpretation of theresults of the examinations. All discontinuities having signalsthat exceed the rejection level as defined by the processrequirements documents shall be rejected unless it is deter-mined from the part drawing that the rejectable discontinuitieswill not remain in the finished part.5.4 Life Cycle ConsiderationsThe referenced NDT prac-tices and
