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1、附录1外文文献原文及译文原文：AnevaluationofNDTmethodsforthelocationandsizingofforgingdiscontinuitiesInselectinganNDTmethodforflawdetectioninforgingsanumberofvariablesmustbeconsidered:a)thetypeofdiscontinuitytobeassessed;b)themethodtobeusedfordetectionandevaluation,andc)thevariablesassociatedwiththef
2、orgingitselfThevariablesinitema)willgovernthelocationwithintheforginganditsorientationwithrespecttoaparticularsurfaceItemb)couldincludeaconsiderablearrayofNDTmethods,butforthepurposeofthispaperonlythesixmostwidelyusedareconsidered一visualtesting(VT),penetrantinspection(PI),magneticparti
3、cleinspection(MI),eddycurrenttesting(ET),radiographicinspection(RT)andultrasonicinspection(UI).Inthelastitemc)thecomponentraceincludesuchthingsascondition,geometryaccessforinspection.a)ForgingdiscontinuitiesThelocationofthediscontinuitywillhaveasignificantinfluenceontheselectionoftheND
4、Tmethodtobeusedandtheyarethereforegroupedintothreecategories,toaidthisselection:1.opentothesurface:laps,seam,burst,slugs,cracksandinclusions2.slightlysubsurface:seam,stringers,inclusionsandgrainstructurevariations3.internal:stringers,burst,lamination,grainstructure,inclusionsandpipingA
5、briefreviewofthesetermsmaybehelpful:Lap:foldedmetal,flattenedintothesurfacebutnotfusingwithitSeam:linearflawsduetooxidizedblowholesoringotsplashes,whichareelongatedbyhotworkingBurst:rupturescausedbyfailureofplasticdeformationbyprocessingattoolowatemperatureorexcessiveworkingofmetalStri
6、ngers:abarstockdefect,duetononmetallicinclusionsbeingsqueezedoutintolongandthinstringsLamination:planardefectalignedparalleltosurface,originatingintheoriginalingotfromrolledoutpipingCracks:transgranularfailure,duetolocalizedstressesresultingfromnon-uniformheatingorcoolingandnon-plastic
7、deformationInclusions:impurities,suchasslag,oxideandsulphides,oftenfromtheoriginalmoltenstageinformingthebilletusedforforgingGrainstructure:dependingupontheextentofworking,(deformationandrecrystllisation)canbeassmallas0.5mmoraslargeas10mmPiping:acavityatthecentreoftheingotorbillet,ca
