1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS ISO 12686:1999 ICS 25.
2、220.40; 25.220.99 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Metallic and other inorganic coatings Automated controlled shot-peening of metallic articles prior to nickel, autocatalytic nickel or chromium plating, or as a final finishThis British Standard, having been prep
3、ared under the direction of the Sector Committee for Materials and Chemicals, was published under the authority of the Standards Committee and comes into effect on 15 February 2000 BSI 02-2000 ISBN 0 580 35904 2 BS ISO 12686:1999 Amendments issued since publication Amd. No. Date Comments National fo
4、reword This British Standard reproduces verbatim ISO 12686:1999 and implements it as the UK national standard. The UK participation in its preparation was entrusted to Technical Committee STI/33, Electrodeposited and related coatings, which has the responsibility to: aid enquirers to understand the
5、text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organizations represented on this commi
6、ttee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by us
7、ing the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunit
8、y from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii to v, a blank page, pages 1 to 34, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last iss
9、ued.Referencenumber ISO12686:1999(E) INTERNATIONAL STANDARD ISO 12686 Firstedition 1999-12-01 Metallicandotherinorganiccoatings Automatedcontrolledshot-peeningof metallicarticlespriortonickel, autocatalyticnickelorchromiumplating,or asafinalfinish Revtements mtalliques et autres revtements inorganiq
10、ues Grenaillage automatique de pices mtalliques avant dpt lectrolytique de nickel, dpt autocatalytique de nickel, ou dpt lectrolytique de chrome, ou en tant que finition de surfaceISO12686:1999(E) ii ISO12686:1999(E)iii Contents Page 1 Scope1 2 Normativereferences1 3 Termsanddefinitions.2 4 Material
11、sandequipment.7 5 Orderinginformation.13 6 Pre-peeningtreatment.13 7 Procedure.14 8 Post-peeningtreatment.16 9 Certificationandtestrecords.17 AnnexA(normative)Freedomfromironcontaminationtest.18 AnnexB(normative)Caststeelshot19 AnnexC(normative)Wireshot21 AnnexD(normative)Characteristicsofceramicsho
12、t23 AnnexE(normative)Almenstrip,holderandgauge25 AnnexF(normative)Calibrationsystemrequirements27 AnnexG(informative)Non-mandatoryinformation31 Bibliography34ISO12686:1999(E) iv Foreword ISO(theInternationalOrganizationforStandardization)isaworldwidefederationofnationalstandardsbodies(ISO memberbodi
13、es).TheworkofpreparingInternationalStandardsisnormallycarriedoutthroughISOtechnical committees.Eachmemberbodyinterestedinasubjectforwhichatechnicalcommitteehasbeenestablishedhas therighttoberepresentedonthatcommittee.Internationalorganizations,governmentalandnon-governmental,in liaisonwithISO,alsota
14、kepartinthework.ISOcollaboratescloselywiththeInternationalElectrotechnical Commission(IEC)onallmattersofelectrotechnicalstandardization. InternationalStandardsaredraftedinaccordancewiththerulesgivenintheISO/IECDirectives,Part3. DraftInternationalStandardsadoptedbythetechnicalcommitteesarecirculatedt
15、othememberbodiesforvoting. PublicationasanInternationalStandardrequiresapprovalbyatleast75%ofthememberbodiescastingavote. InternationalStandardISO12686waspreparedbyTechnicalCommitteeISO/TC107, Metallic and other inorganic coatings, Subcommittee SC 3, Electrodeposited coatings and related finishes. A
16、nnexesAtoFformanormativepartofthisInternationalStandard.AnnexGisforinformationonly.ISO12686:1999(E)v Introduction Shot-peeningisaprocessforcold-workingsurfacesbybombardingtheproductwithshotofasolidandspherical naturepropelledatarelativelyhighvelocity.Ingeneral,shotpeeningwillincreasefatiguelifeofapr
17、oductthatis subjecttobendingortorsionalstress.Itwillimproveresistancetostress-corrosioncracking.Itcanbeusedtoform partsorcorrecttheirshapes.SeeannexGforadditionalinformation. Itisessentialthattheshot-peeningprocessparametersberigidlycontrolledtoensurerepeatabilityfromparttopart andlottolot. ThisInte
18、rnationalStandarddescribestechniquesandmethodsnecessaryforpropercontroloftheshotpeening process.INTERNATIONALSTANDARD ISO12686:1999(E)1 MetallicandotherinorganiccoatingsAutomatedcontrolled shot-peeningofmetallicarticlespriortonickel,autocatalytic nickelorchromiumplating,orasafinalfinish 1 Scope This
19、InternationalStandarddescribestherequirementsforautomated,controlledshot-peeningofmetallicarticles priortoelectrolyticorautocatalyticdepositionofnickelorchromium,orasafinalfinish,usingshotmadeofcast steel,conditionedcutwire,ceramicshotorglassbeads.Theprocessisapplicabletothosematerialsonwhichtest wo
20、rkhasshownittobebeneficialwithingivenintensityranges.Itisusuallynotsuitableforbrittlematerials.Hand- peeningandrotaryflap-peeningarespecificallyexcluded. Shot-peeninginducesresidualcompressivestressesinthesurfaceandnearsurfacelayersofmetallicarticles,and changesthesurfacemicrostructure(includingphas
21、etransformation),therebycontrollingorlimitingthereductionin fatiguepropertiesthatoccursfromnickelorchromiumplatingofthearticle,orincreasingthefatiguepropertiesof unplatedarticles. 2 Normativereferences Thefollowingnormativedocumentscontainprovisionswhich,throughreferenceinthistext,constituteprovisio
22、nsof thisInternationalStandard.Fordatedreferences,subsequentamendmentsto,orrevisionsof,anyofthese publicationsdonotapply.However,partiestoagreementsbasedonthisInternationalStandardareencouragedto investigatethepossibilityofapplyingthemostrecenteditionsofthenormativedocumentsindicatedbelow.For undate
23、dreferences,thelatesteditionofthenormativedocumentreferredtoapplies.MembersofISOandIEC maintainregistersofcurrentlyvalidInternationalStandards. ISO565:1990, Test sieves Metal wire cloth, perforated metal plate and electroformed sheet Nominal sizes of openings. ISO2194:1991, Industrial screens Woven
24、wire cloth, perforated plate and electroformed sheet Designation and nominal sizes of openings. ISO3310-1:1990, Test sieves Technical requirements and testing Part 1: Test sieves of metal wire cloth. ISO3453:1984, Non-destructive testing Liquid penetrant inspection Means of verification. ISO6933:198
25、6, Railway rolling stock material Magnetic particle acceptance testing.ISO12686:1999(E) 2 3 Termsanddefinitions ForthepurposesofthisInternationalStandard,thefollowingtermsanddefinitionsapply. 3.1 Almenstrip UNSG10700carbonsteelspecimensthatareusedtocalibratetheenergyofashot-peeningstream(seeFigure1)
26、 3.2 Almenstripholdingfixture fixtureforholdingAlmenstripsinsuitablelocationsthatrepresentthepositionandangularorientationofthe surfacesofapartwhereintensityistobedeterminedandverified(seeFigure2) 3.3 archeight flatAlmenstripswhich,whensubjectedtoastreamofshotmovingatanadequatevelocity,willbendinana
27、rc correspondingtotheamountofenergytransmittedbytheshotstream NOTE Theheightofthecurvedarcmeasuredinmillimetresisthearcheight,measuredbyanAlmengauge(seeFigure3). 3.4 automaticequipment shot-peeningequipmentinwhichparts,fixtures,nozzlesandpeeningparametersarepresetbyhandorbylocating fixturesandverifi
28、edbyinspectionpersonnel NOTE Peeningtimeismonitoredautomaticallyandairpressureorwheelspeedissetmanually. 3.5 residualcompressivestresses layerincompressionbelowthesurfacecreatedbycold-workingorstretchingthesurfacebeyondtheelasticlimitby shot-peening NOTE Thedepthofcompressivestressesismeasuredfromth
29、ecrownofthedimpletothedepth. 3.6 coverage extentofobliterationoftheoriginalsurfacebydimplesproducedbyimpactfromindividualshotparticles,expressed asapercentage NOTE 100%coverageisdefinedasthatleaving2%orlessoftheoriginalsurfaceunpeenedbecausetheestimationof coverageoftheimpressionsisdifficultwhenthis
30、isabout98%ofthetotalsurface.“100%coverage“isatheoreticallimiting value.Hence,theterm“completecoverage“ispreferred.Usually,completecoveragerequiresincreasingthebasetime,i.e.the timeofpeeningtoreach98%coverage,by15%to20%.Valuesof200%to300%,etc.areobtainedbymultiplyingthisrun timeby2,3,etc. 3.7 depthof
31、compressivestresses wherethestressprofilepassesthroughzerostress 3.8 shotpeeningintensity Almenstriparcheightatsaturation NOTE Archeightisnotcorrectlytermedintensityunlesssaturationisachieved. 3.9 liquidtracersystem liquidcoatingmaterialbearingapigmentthatfluorescesunderanultravioletlightandisremove
32、datarate proportionaltopeeningcoverageISO12686:1999(E)3 Dimensionsinmillimetres Key 1TeststripA 2TeststripC 3TeststripN NOTES Analysisofstock:UNSG10700 Cold-rolledspringsteel Squareedgenumberone(on76,2mmedge) Finish:bluetemper(orbright) Uniformlyhardenedandtemperedto44HRCto50HRC FlatnessC 0,038mmarc
33、height FlatnessNandA 0,025mmarcheight Figure1AlmentestspecimenISO12686:1999(E) 4 Dimensionsinmillimetres Key 1 FourM5panheadmachinescrewswithhexagonalnuts 2 Fourholesofdiameter5,6mm 3 Holder 4 Teststrip(sectioned) Figure2AssembledteststripandholderISO12686:1999(E)5 Dimensionsinmillimetres a Fourhard
34、enedsteelballs b Dialindicatortobegraduatedinvaluesof0,025mm(0,0254mmpermitted);maximumextensionforce25gf c Contactsurfaceofallballstobeinoneplane 0,05mm Key 1 Guides Figure3AlmengaugeISO12686:1999(E) 6 3.10 microprocessor-controlledequipment peeningequipmentthathasnozzle-holdingfixturesandiscompute
35、r-controlledforprocessing,monitoringand documentationofthepeeningparameterscriticaltoprocesscertification 3.11 nozzle-holdingfixture fixturethatholdsthenozzlesattherequiredlocation,distanceandangleinalockedpositionduringthepeening operation 3.12 process-interruptparameters forcriticalpeeningoperatio
36、ns,parameterssuchasshotflow,airpressure,rotationalspeedofparts(s 1 ),oscillation rateandcycletimethatmustbemonitoredwithinprocessrequirements 3.13 saturation minimumdurationofpeeningnecessarytoachievethedesiredAlmenintensitywhich,whendoubled,doesnot increasetheAlmenstriparcheightbymorethan10% 3.14 s
37、aturationcurve curvethatplotspeeningtimeontheAlmenstrip(abscissa)versusAlmenstriparcheight(ordinate)achievedfor thepeeningtime(seeFigure4) 3.15 surfaceobliteration conditionofapeenedsurfaceinwhich100%ofthesurfacehasbeendimpledwithshotimpressions Figure4SaturationcurveISO12686:1999(E)7 4 Materialsand
38、equipment 4.1 Shotmaterialcomposition 4.1.1 Caststeelshot,conformingtotherequirementsgiveninannexB. 4.1.2 Cutwireshot,madefromcold-finished,roundwire,conformingtoannexC. 4.1.3 Ceramicshot(beads),conformingtothechemicalcompositiongiveninTable1andinannexD. 4.1.4 Glassbeads,freefromleadandfreesilicaand
39、maintaineddryandfreefromanysurfacecontaminationor dressings.Glassbeadsshallhaveanominalcompositionof72,5%SiO 2 ,9,75%CaO,13%Na 2 O,3,3%MgO, 0,75%ofotherminorelementsandaspecificgravityof2,5g/cm 3 . Table1Compositionofceramicshot ZrO 2 % SiO 2 % Al 2 O 3 % Fe 2 O 3 % Freeiron % Specificgravity g/cm 3
40、 60to70 28to33 10max 0,1max. 0,1max. 3,6to3,95 4.2 Shotformandshape 4.2.1 Caststeel Caststeelshotshallbesphericalafterpre-conditioningandfreefromsharpedges,cornersandbrokenpieces.It shallconformtotheacceptableshapesgiveninFigure5.Thenumberofnonconformingshapes(seeFigure6) shallnotexceedthevaluesgive
41、ninTable2. Table2Maximumallowablenonconformingshapes caststeel,cutwireandceramicshot(asshowninFigure6) Caststeelsize Cutwiresize Ceramicsize Maximumallowable nonconformingshapes perarea(1cmX1cm) 930 5 780 5 660 CW62 12 550 CW54 12 460 CW47 15 390 CW41 80 CW35 80 330 CW32 Z850 80 280 CW28 80 230 CW23
42、 Z600 80 190 CW20 80 170 Z425 80 130 480 110 Z300 640 70 Z210 640ISO 12686:1999(E) 8 ISO 1999 All rights reserved Not necessarily spheres but all corners rounded Figure 5 Acceptable shapes Key 1 Nodulated shot 2 Hollow shot 3 Elongated shot U V | W | (see Table 2; diameter to length ratio 1:2) 4 Bro
43、ken, sharp-cornered shot (see Tables 4, 6 and 7) Figure 6 Unacceptable shapes 4.2.2 Cut wire Cut wire shot shall be spherical after pre-conditioning. It shall be free from sharp edges, corners and broken pieces. The number of nonconforming shapes shall not exceed the values given in Table 2. 4.2.3 C
44、eramic shot Ceramic shot shall be spherical and free from sharp edges, corners and broken pieces. The number of nonconforming shapes shall not exceed the values given in Table 2. 4.3 Hardness The hardness of the shot shall exceed that of the material to be processed.ISO12686:1999(E)9 4.3.1 Caststeel
45、 CaststeelshotshallhaveahardnessofHRC45toHRC55.Specialhardcaststeelshotshallbeusedonproducts harderthanHRC50andshallhaveahardnessofHRC55toHRC65. 4.3.2 Cutwire CutwireshotshallhaveahardnessequaltoorgreaterthanthatgiveninTable3. Table3Hardness,cutwireshot Shotsize Minimumhardness RockwellC CW62 36 CW5
46、4 39 CW47 41 CW41 42 CW35 44 CW32 45 CW28 46 CW23andfiner 48 4.3.3 Ceramicshot Ceramicshotshallhaveaminimumhardnessof560HV30(30kgf). 4.3.4 Glassbeads Glassbeadsshallhaveahardnessof5,5ontheMohscale. 4.4 Size Thesizeoftheshotshallconformtothefollowing: a) thesizeoftheshotshallbecapableofproducingthere
47、quiredintensityintherequiredtime; b) ifapeenedsurfacecontainsafillet,thenominalsizeoftheshotshallnotexceedone-halfoftheradiusofthe fillet; c) iftheshotmustpassthroughanopening,suchasaslot,toreachapeenedsurface,thenominalsizeofthe shotshallnotexceedone-fourthofthewidthofthediameteroftheopening. 4.4.1
48、 Caststeel CaststeelshotchargedintoamachineshallconformtothescreenrequirementsgiveninTable4forthenominal sizeselected.SievesshallbeinaccordancewithISO565,ISO2194andISO3310-1.ISO12686:1999(E) 10 Table4Screensize,caststeelshot(asshowninFigure6) Size ofshot Allpass screensize mm Maximum 2%onscreen mm M
49、aximum 50%onscreen mm Cumulative 9%onscreen mm Maximum 8%onscreen mm Maximum number ofdeformedshot acceptableper area (1cmX1cm) 930 4,000 3,350 2,800 2,360 2,000 5 780 3,350 2,800 2,360 2,000 1,700 5 660 2,800 2,360 2,000 1,700 1,400 12 550 2,360 2,000 1,700 1,400 1,180 12 460 2,000 1,700 1,400 1,180 1,000 15 390 1,700 1,400 1,180 1,000 0,850 20 330 1,400 1,180 1,000 0,850 0,710 80 280 1,180 1,000 0,850 0,710 0,600 80 230 1,000 0,850 0,710 0,600 0,500 80 190 0,850 0,710 0,600 0,500 0,425 80 170 0,710 0,600 0,500 0,425 0,355 8
