1、Designation: E 2533 09Standard Guide forNondestructive Testing of Polymer Matrix Composites Usedin Aerospace Applications1This standard is issued under the fixed designation E 2533; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, t
2、he 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. Scope1.1 This guide provides information to help engineers selectappropriate nondestructive testing (NDT) methods to
3、 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 consensus standards and that arecurrently used by industry. Specific practices and test meth
4、odsare not described in detail, but are referenced. The referencedNDT practices and test methods have demonstrated utility inquality assurance of PMCs during process design and optimi-zation, process control, after manufacture inspection, in-service inspection, and health monitoring.1.2 This guide d
5、oes 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 polymeric matrix composites: AcousticEmission, Computed Tomography, Leak Testing, Radi
6、ography,Radioscopy, Shearography, Strain Measurement (contact meth-ods), Thermography, Ultrasound, and Visual NDT.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 polymer matrixcomposi
7、tes. Additional information is provided about the useof currently active standard documents (an emphasis is placedon applicable standard guides, practices, and test methods ofASTM Committee E07 on Nondestructive Testing), geometryand size considerations, safety and hazards considerations, andinforma
8、tion about physical reference standards.1.5 To ensure proper use of the referenced standard docu-ments, there are recognized NDT specialists that are certified inaccordance with industry and company NDT specifications. Itis recommended that a NDT specialist be a part of anycomposite component design
9、, quality assurance, in-servicemaintenance or damage examination.1.6 This guide summarizes the application of NDT methodsto fiber- and fabric-reinforced polymeric matrix composites.The composites of interest are primarily, but not exclusivelylimited to those containing high modulus (greater than 20
10、GPa(33106psi) fibers. Furthermore, an emphasis is placed oncomposites with continuous (versus discontinuous) fiber rein-forcement.1.7 This guide is applicable to polymeric matrix compositescontaining but not limited to bismaleimide, epoxy, phenolic,poly(amide imide), polybenzimidazole, polyester (th
11、ermoset-ting and thermoplastic), poly(ether ether ketone), poly(etherimide), polyimide (thermosetting and thermoplastic),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
12、uniaxial laminae, cross-ply laminates, angle-ply laminates, andstructural sandwich constructions. The composite componentsmade therefrom include filament-wound pressure vessels,flight control surfaces, and various structural composites.1.9 The values stated in SI units are to be regarded as thestand
13、ard. The values given in parentheses are provided forinformation only.1.10 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 th
14、e applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2C 274 Terminology of Structural Sandwich ConstructionsD 3878 Terminology for Composite MaterialsE 543 Specification for Agencies Performing Nondestruc-tive TestingE 1316 Terminology for Nondestructive
15、Examinations2.2 ASNT Standard:SNT-TC-1A Recommended Practice for Personnel Qualifi-cation and Certification in Nondestructive Testing31This guide is under the jurisdiction of ASTM Committee E07 on Nondestruc-tive Testing and is the direct responsibility of Subcommittee E07.10 on SpecializedNDT Metho
16、ds.Current edition approved May 15, 2009. Published July 2009.2For 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
17、.3Available from American Society for Nondestructive Testing, P. O. Box 28518,1711 Arlington Lane, Columbus, OH 43228-0518.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.2.3 ASTM Adjuncts:Curing Press Straining block (13 Drawings)43
18、. Terminology3.1 AbbreviationsThe following abbreviations areadopted in this guide: Acoustic Emission (AE), ComputedRadiography (CR), Computed Tomography (CT), Digital Ra-diology (DR), Leak Testing (LT), Radiography (RT), Radios-copy (RTR), and Ultrasound (UT).3.2 DefinitionsDefinitions of terms rel
19、ated to NDT ofaerospace composites which appear in Terminology E 1316and Terminology D 3676 shall apply to the terms used in theguide.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 organizationt
20、he company,government agency, or other 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
21、 other,as appropriate.3.3.3 composite materialsee Terminology D 3878.3.3.4 composite componenta finished part containingcomposite material(s) that is in its end use application configu-ration, and which has undergone processing, fabrication, andassembly to the extent specified by the drawing, purcha
22、seorder, or contract.3.3.5 composite shella 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 orie
23、ntation, and compositeshell thickness may vary from point-to-point.3.3.6 disbondsee Terminology D 3878.3.3.7 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 materi
24、al. The vessel may be cylindrical orspherical 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 fu
25、nction.3.3.9 microcrackinvisible cracks (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 Testin
26、g Any composite materialor component acrosswhich 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 co
27、stsincrease as the requiredleak test sensitivityincreases.Qualitative indications,for example bubbles, orquantitativemeasurements, forexample, detectordeflections, thatascertain the presenceor location, orconcentration or leakrate of a leaking fluid.Different techniques areavailable forcharacterizat
28、ion of largeleaks (with rates as highas 10-2Pa m3s-1(10-1std cm3s-1) and smallleaks (rates less then10-5Pa m3s-1(10-4stdcm3s-1).Radiography,Computed Radiology,Radiology with DigitalDetector Arrays,RadioscopyPrimarily detects sub-surface imperfections ordiscontinuities such asporosity sometimes possi
29、ble fromdigital images aftercalibration 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. Dig
30、italtechniques (CR, DDA)are usually faster.Radiation safety. Inradioscopy, radiationsafety more problematicif a moving source isused, versus movementof part.E2533094TABLE 2 ContinuedNDT Method Applications Advantages LimitationsWhat Is Seenand Reported?Other ConsiderationsShearography Detects subsur
31、faceimperfections ordiscontinuities orchanges in modulus orout-of-plane deformation.Well suited for highspeed, automatedinspection in productionenvironments.Subsurface imperfectionor discontinuity must besufficiently large tocause measurablesurface disdeformationunder load. Surfacecondition, especia
32、llyglossiness, can interferewith accurateshearographic 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 strainc
33、oncentrations.Additional equipment isrequired to determinesurface derivative slopechanges, and thus usethe method as aquantitative tool.Strain Measurement Can be used to measurestatic and dynamictensile and compressivestrain, as well asshearing, Poisson,bending, and torsionalstrains.Relatively inexp
34、ensive,and less bulky and betterresolution thanextensometers (canachieve an overallaccuracy of better than6 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 th
35、e resistivity, andhysteresis and creepcaused by imperfectbonding.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 straingauge
36、s are available (forexample, semiconductorwafer sensors, 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, low
37、reflectivity/high emissivitysurfaces, and inmaterials which dissipateenergy efficiently,Quick observation oflarge surfaces andidentification of regionsthat should be examinedmore carefully.Composites havetemperature limitsbeyond whichirreversible matrix andfiber damage can occur.Imperfection ordisco
38、ntinuity detectiondepends on orientationof an imperfection ordiscontinuity relative tothe direction of heat flow.In thicker materials, onlyqualitative indications ofimperfections ordiscontinuities arepossible.The aerial temperaturedistribution is measuredby mapping contours ofequal temperature(isoth
39、erms), thus yieldinga heat emission patternrelated to 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 subdivi
40、ded intopulse or lock-intechniques.Ultrasound Detects sub-surfaceimperfections ordiscontinuities. There aretwo primary techniques;pulse echo for one sidedinspections and throughtransmission for twosided inspections.Detects sub-surfaceimperfections ordiscontinuities includingporosity, inclusions, Pos
41、siblefluid absorption intoporous materials such ascomposites. Numeroustechniques availableincluding longitudinal,shear or surface waves.Attenuation can becomparatively high inPMCs compared tometallic articles.Visual NDT Detects disruptions onsurfaces being viewed.Low cost. Detect surfaceimperfection
42、s ordiscontinuities includingdelaminations, fiberbreakage, impactdamage.Requires direct line ofsight.Imperfections ordiscontinuities aredirectly recorded oninspectiondocumentationsometimes photographs.Can find imperfections ordiscontinuities on insidediameters if a centralconductor can beinserted an
43、d satisfactoryelectrical contact made.E2533095results 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 re
44、main in the finished part.5.4 Life Cycle ConsiderationsThe referenced NDT prac-tices and test methods have demonstrated utility in qualityassurance of PMCs during the life cycle of the product. Themodern NDT paradigm that has evolved and matured over thelast twenty years has been fully demonstrated
45、to providebenefits from the application of NDT during: (a) product andprocess design and optimization, (b) on-line process control,(c) after manufacture inspection, (d) in-service inspection, (e)and health monitoring.5.4.1 In-process NDT can be used for feedback processcontrol since all tests are ba
46、sed upon measurements which donot damage the article under test.5.4.2 The applicability of NDT methods to evaluate PMCmaterials and components during their life cycle is summarizedin Tables 3 and 4.5.5 General Geometry and Size ConsiderationsPart con-tour, curvature, and surface condition may limit
47、the ability ofcertain tests to detect imperfections with the desired accuracy.5.6 ReportingReports and records shall be specified byagreement between purchaser and supplier. It is recommendedthat any NDT report or archival record contain information,when available, about the material type, method of
48、 fabrication,manufacturers name, part number, lot, date of lay-up and/or ofcure, date and pressure load of previous tests (for pressurevessels), and previous service history (for in-service and failedcomposite articles). Forwards and backwards compatibility ofdata, data availability, criticality (le
49、ngth of data retention),specification change, specification revision and date, softwareand hardware considerations will also govern how reporting isperformed.6. Procedure6.1 When NDT produces an indication of a material discon-tinuity, the indication is subject to interpretation as false,nonrelevant, or relevant (Fig. 1). If the indication has beeninterpreted as relevant, the necessary subsequent evaluationwill result in the decision to accept or reject the compositematerial or component.7. Acoustic Emission7.1 Referenced Documents7.1.1 ASTM Standards:2E 569 Practice
