Designation:F2257−14StandardSpecificationforWroughtSeamlessorWeldedandDrawn18Chromium-14Nickel-2.5MolybdenumStainlessSteelSmallDiameterTubingforSurgicalImplants(UNSS31673)1ThisstandardisissuedunderthefixeddesignationF2257;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope*1.1Thisspecificationcoverstherequirementsforwrought18chromium-14nickel-2.5molybdenumstainlesssteeltubingusedforthemanufactureofsurgicalimplants.MaterialshallconformtotheapplicablerequirementsofSpecificationF138(forseamless)orSpecificationF139(forweldedanddrawn).Thisspecificationaddressesthoseproductvariablesthatdif-ferentiatesmall-diametermedicalgradetubingfromthebar,wire,sheet,andstripproductformscoveredinthesespecifi-cations.1.2Thisspecificationappliestocoldfinishedstraightlengthtubingwith3mm[0.125in.]andsmallernominaloutsidediameter(OD)and0.5mm[0.020in.]andthinnernominalwallthickness.1.3Thespecificationsin2.1arereferredtoastheASTMmaterialstandard(s)inthisspecification.1.4Thevaluesstatedineitherinch-poundorSIunitsaretoberegardedseparatelyasstandard.Inch-poundunitsareshowninparentheses.Thevaluesstatedineachsystemmaynotbeexactequivalents;therefore,eachsystemshallbeusedinde-pendentlyoftheother.Combiningvaluesfromthetwosystemsmayresultinnon-conformancewiththestandard.2.ReferencedDocuments2.1ASTMMaterialStandards:2F138SpecificationforWrought18Chromium-14Nickel-2.5MolybdenumStainlessSteelBarandWireforSurgicalImplants(UNSS31673)F139SpecificationforWrought18Chromium-14Nickel-2.5MolybdenumStainlessSteelSheetandStripforSur-gicalImplants(UNSS31673)2.2ASTMStandards:2A632SpecificationforSeamlessandWeldedAusteniticStainlessSteelTubing(Small-Diameter)forGeneralSer-viceE8/E8MTestMethodsforTensionTestingofMetallicMa-terialsE29PracticeforUsingSignificantDigitsinTestDatatoDetermineConformancewithSpeci...
