Multilayer Insulation Material Guidelines

1 ,MarshallSpaceFlightCenter, ,Huntsville,AlabamaNationalAeronauticsan dSpaceAdministrationMarshallSpaceFlightC enter MSFC, ,notasgenericterms(forexample,notallhook -and-pilefastenersareVelcrobrand).3 MCo.:Nextel, :Dacron,Kapton,Kevlar,Mylar,Nomex,Nylon, Tedlar,TeflonKamenWipingMaterials,Inc.:R ympleclothTexwipeCo.:Alpha10wipeVelcroUS A,Inc.:Velcro,Hi-GardeAvailablefrom:NASA C enterforAeroSpaceInformation800 ElkfidgeLandingRoadLinthicumHeights,MD21 090-2934(301)621-0390 NationalTechnicalInformationService5285 PortRoyalRoadSpringfield,VA22161(703) (Continued) 'spayloadbayisseenherewiththeSpacelabmod ule(right)andcrewtransfertunnel(lefttoce nter) ,forupto2wkatatime, ,dependingontheirorientationrelativetoth elineofflight, (a) ,ahaircover, (thesameasforpotatochipbags) (b)Twotechnicians,alsowearingglovesandfa cemasks, ,andaneatlystitchedcutoutstrip,fromthele ftside,foraprotrusion(Boeingphotos).

2 Severalreflectors'layersarestitchedtomak eacompleteblanket(photocourtesyofBoeing) ..22, (a)beforeand(b) (c)Kaptonand(d) , ,slowerdebrisposesagreaterhazardtoMLIwhi chcanerodewithlongexposure, (6in.)..25 VLISTOFFIGURES(Continued),Toprotectareas wheretheMLIhaddegradedinorbit(a),astrona utsappliedMLIrepairpatches(b)totheexteri oroftheHubbleSpaceTelescope(c)duringtheJ anuary1997servicingmission(STS-82). ,thealuminizedpolyimidelayersareelectric allyconnectedbyaluminumfoil(thegrounding insert),andametalgrommetthroughtheblanke tconnectsthelayerstothegroundstrap(froma Boeingdrawing).. , , , , , (nowpartofBoeingCo.)MaterialsandProcesse sMultilayerinsulationMarshallSpaceFlight CenterMaterialsUsageAgreementNationalAer onauticsandSpaceAdministrationPolytetraf luoroethyleneSpaceStationFreedom(nowISS) ,multilayerinsulation(MLI) ,anMLIdesignmayrangefromafewsimpleblanke tstoaseriesofsubblanketstofitcomplexgeom etries( ).

3 Typically, ,anumberofguidelinesmustbefollowedinsele ctingmaterials,designingthemintothespace craft, (Sectionofbookinparentheses)OuterCover( )"LightBlock(ifnecessary)MetallizedRefle ctor( )[NettingSpacer( )(15to20 Reflector/SpacerLayers,Total)MetallizedS eflector( )NettingSpacer( )IInnerCover( )Structure/_ IAdhesiveTransferTape( )GlassFabricTape( )Adhesives( )MetallizedTape( )GroundingTape( )/ExposedThreads( )NonexposedThreads( )Hook-and-PileConnectors( ) , ( )andtheLong-DurationExposureFacility(LDE F)( ),andoutlinesotherconcerns( ). 'spayloadbayisseenherewiththeSpacelabmod ule(right)andcrewtransfertunnel(lefttoce nter) ,forupto2wkatatime, ,dependingontheirorientationrelativetoth elineofflight, ,withspecifications,sources.]

4 , ,endorsement,orpreference,eitherexpresse dorimplied, ,eachdesignmustmeettheoutgassingrequirem entsofSP-R-0022 Aand,ifinvolvingline-of-sightproximityto sensitiveoptics, , ,thelatestmanufacturer' , 'latestcatalogsandspecifications,whichar eupdatedfrequently, , ,OdorandOffgassingRequirementsandTestPro ceduresforMaterialsinEnvironmentsthatSup portCombustionMeteoroidEnvironmentModel( Near-EarthtoLunarSurface)MeteoroidEnviro nmentModel(InterplanetaryandPlanetary) ,Glass;Tape,TextileGlass;andThread,Glass andWire-ReinforcedGlassFastenerTapes,Hoo kandPile,SyntheticFilmsandPlasticSheets, PolyesterandPolyimideStandardsandSpecifi cations,OrderofPreferencefortheSelection ofThread,Nylon,Non-melting(Typicallyrepl acedbyA-A-50195) ,ControlledEnvironment(Notitlegiven) (SingleRip)

5 MethodPeelAdhesionofPressure-SensitiveTa peat180*AnglePeelAdhesionofPressure-Sens itiveTapeUsedforElectricalandElectronicA pplicationsGlassFiberCordandSewingThread TestMethodforEmittanceofSurfaceSolarCons tantandAirMassZeroSolarSpectralIrradianc eTablesStandardTestMethodforTotalMassLos sandCollectedVolatileCondensableMaterial sfromOutgassingmaVacuumEnvironmentSolarA bsorptance,Reflectance, ,specifications, , ( ). , < >10-5torr,theconductivityoftheMLIquicklyr evertstoapproximatelytheconductivityofai r,thusdegradingtheMLIblanket' ,bywayofaMaterialsUsageAgreement(MUA),th atmaterialsusedinthefabricationofMLIblan kethardwaremeetallofthespacecraftmateria lsrequirementsbyconsideringthenonoperati onalandoperationalrequirementsforthepart icularapplication,designengineeringprope rtiesofthecandidatematerials, ,butarenotlimitedto,nonoperationalandope rationalthermallimits,loads,fluidenviron ments,chargedparticles,ultraviolet(UV)

6 Radiation,electricalbondingandgrounding, contamination, ,storage,handling, ,MLImaterialsfallintotwobroadcategorieso fbasematerials,inorganicandorganic, (andprincipaltradenames)are:Inorganic:Fi berglasswovencloth(Betacloth)Organic:Pol yesterorPET(Mylar),polytetrafluoroethyle neorPFTE(Teflon),polyimide(Kapton),polyf luorovinylorPVF(Tedlar).7(a)(b)Figure5.( a) ,ahaircover, (thesameasforpotatochipbags) (b)Twotechnicians,alsowearingglovesandfa cemasks, ,andaneatlystitchedcutoutstrip,fromthele ftside,foraprotrusion(Boeingphotos). ,flaking, , , (AO).NASATM-104748containsdataonthefailu reofalooserweaveBetacloth(SheldahlG41450 0) , ,byanexposureof500equivalentSunhourstoUV radiationinvacuum, , , , , , (pores)inmanufacturers' ,madeeitherbyaneedle(perforation)orahole punch(porolation).

7 Becausemanypatterns,holesizes,andholeden sitiesareavailable, , ,Ted,,Kaplon,Teflon,Tollon,AluminizedRei nforcedCoated&BackedBackedCoated& ,trans-Fiberglasswovenclothimpregnatedwi thPTFET eflon(500F:nosilicone)Fiberglasswovenclo thimpregnatedwithPTFET eflonwithonesidealuminizedopenweaveNomex bondedw/polyesteradhesive,onesidealumini zedparentindiumtinoxideconductiveFcoatin gandIaluminumbackingFEPT eflon,vacuumdepositedsilverandInconelbac kinglayersTeflon,transparentindiumtinoxi deconductivecoatingandsilverilnconelback ingVendorsChemfabChemfab,OunmoreSheldahl ,DunmoreSheldahl,DunmoreSheldahl,Ounmore Sheldahl,OunmoreWeavePlainPlainTexture,w arpxfill,yamgcm(_n.)

8 32x24(85x60)32x24(85x60)N/AN/A!NIAN/AYar nfiberdiam,mm(in.) (104( ) ( )Fabric/filmthickness,cm(in.) ( ) ( ) ( )+20%[1](1][1]Weight,gm/cm2(Ib/yd2) ( ) (( )[11(2][3]Tensilestrength, ,ko/cm(Ib/in)16(90)16(90)---Fill,ko/cm(I b/in) (60) (GO)Elongationatbreak,% ,kg(Ib), ( ) ( ) ,"C(1:)Continuous,min/rnax-72/107(-100/2 25)<175(350)<204(400)-73/65(-100/150)Int ermittent,rain/max-184/150(300/300)-184/ 260(-3ooK,oo)<2o4(400)-73/65(-100/150)Te flonbyweight,%17-2217-22-Aluminumthickne ss,_350-Sudaceresistivity,fl/square250,0 00250,000 Solarabsorptance(a), (whiteside) (VDAside) [1] (e), (whiteside) (VDAside) [1112][31 EnvironmentalcompatibilityAO,UVAO,UVSoor t-termAOShort-termAOShort-termk,OShort-t ermAOLon0-termUVLong-termLIVLong-termINF lightuseLDEF,OV,/SSEOIM-3,ISSHST,LDEF-HS T,LDEFW eight,solarabsorptance,andinlraredemissi vitylotcoversofvaryiqthicknesses[1]Kapto n[2]Teflon,backed[3]Teflon,coatedThickne sscm(mil)i( {10,0)))))}

9 ]gm/cm2(Ib/yd2) ( ) ( ) ( ) ( ) ( ) (Ib/yd2}egrWcm2(Ib/yd2) ( ) ( ) ( ) ( ) ( ) ) ( ) ( ) (LEO) , (useASTM-E408-71). ,mm(mil)metal,AWeight,gm/cm2(oz/yd2) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )Temperature,"C('F)Continuous,max/minInt ermittent,max/minAbsorptance,a(max/typ)I nfraredemittance,eAluminizedKaptonMDAC-S TM0691,iTypeII,Class1,GradeASingleordoub lealuminizedGoldlzedKaptonRockwellMB0135 -038,TypeII,Class1,GradeASingleordoubleg oldizedAluminizedMylarMDACSTM0691,TypeII ,Class1,GradeADoublealuminizedSheldahl,D unmoreSheldahlSheldahl, ( )1, ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )-250/288(-420/550)-420/750(-250/400) ; ; [21-250/+288(-420/550)-250/+400(-420/750 ) ; ; [ ( )1, ( ) ( ) ( ) ( ) ( ) ( ) ( )-250193(-420/200)11]-250/150(-4201300).

10 ,DunmoreSheldahl, ( );300( );30026o(5oo)< < (500)< < [1]Temperaturerangefordouble-aluminizedM ylarmaybelimitedto120"C(250"F) [2]Kapton, ,cm(in.) ( ) ( ) ( ) ( )0, ( ) ( ) [3]Mylar,singlealuminizedThickness,cm(in .) ( ) ( ) ( )[ ( ) ( ) ( )I0'27I0' (a) ,MDAC--STM0605-03 Description100%polyesterfabric100%Nomexa ramidmesh1fabricmesh2 VendorsApexMillsStem&SternTextiles, ,mm(in.) + ( ) + ( )ConstructionMeshes/cm2( ) (50 8) (51 8)Denierfilaments4040 Wei0ht,gm/rn2(oz/yd2) + ( + ) + ( )Burststrength, (10) (10)(Ib/in.)Temperaturerangecontinuous," C(*F)-70+120(-94+250)continuous-70+177(- 94+350)intermittent-70+120(-94+250)conti nuous-70+177(-94+350)intermittent1 Dacronnettingmayshrinkandmeltabove177"C( 350"F) , , ,vendorshavestartedofferingcomplexlamina tescomprisingreflective,impact-resistant ,andstructuralmaterialsplusseveralmetalc oatings, , ,TypeII,Class2,RockwellMB0135-048,TypeII ,LAC-22-4448(G);varieswiththefilmGradeBC lass2,GradeBandfabricusedDescriptionPoly imidereinforcedwitharamidDoublegoldizedp olyimidereinforcedAluminizedpolyimdewith fiberglass(Nomexorequivalent)openweavewi tharamid(Nomexorequivalent)backingfabric .]