1、Designation: F75 12Standard Specification forCobalt-28 Chromium-6 Molybdenum Alloy Castings andCasting Alloy for Surgical Implants (UNS R30075)1This standard is issued under the fixed designation F75; the number immediately following the designation indicates the year of originaladoption or, in the
2、case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A superscriptepsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers the chemical, mechanical, andmetallurgical requirements for c
3、obalt-28 chromium-6 molyb-denum alloy unfinished investment product castings for surgi-cal implant applications and casting alloy in the form of shot,bar, or ingots to be used in the manufacture of surgicalimplants. This specification does not apply to completedsurgical implants made from castings.1
4、.2 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsystem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith t
5、he standard.2. Referenced Documents2.1 ASTM Standards:2A957 Specification for Investment Castings, Steel and Al-loy, Common Requirements, for General Industrial UseE3 Guide for Preparation of Metallographic SpecimensE8/E8M Test Methods for Tension Testing of MetallicMaterialsE18 Test Methods for Roc
6、kwell Hardness of Metallic Ma-terialsE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE165 Practice for Liquid Penetrant Examination for GeneralIndustryE354 Test Methods for Chemical Analysis of High-Temperature, Electrical, Magnetic, and Other Simila
7、r Iron,Nickel, and Cobalt AlloysE407 Practice for Microetching Metals and AlloysE601 Test Method for Measuring Electromotive Force(emf) Stability of Base-Metal Thermoelement Materialswith Time in AirF629 Practice for Radiography of Cast Metallic SurgicalImplantsF981 Practice for Assessment of Compat
8、ibility of Biomate-rials for Surgical Implants with Respect to Effect ofMaterials on Muscle and Bone2.2 Aerospace Material Specification:3AMS 2248 Chemical CheckAnalysis Limits: Corrosion andHeat Resistant Steels and Alloys, Maraging and OtherHighly-Alloyed Steels, and Iron AlloysAMS 2269 Chemical C
9、heck Analysis Limits: Nickel,Nickel Alloys and Cobalt Alloys2.3 ISO Standards:4ISO 5832-4 Implants for SurgeryMetallic MaterialsPart 4: Cobalt-Chromium-Molybdenum Casting AlloyISO 6892 Metallic MaterialsTensile Testing at AmbientTemperatureISO 9001 Quality Management SystemsRequirements3. Terminolog
10、y3.1 Definitions of Terms Specific to This Standard:3.1.1 investment casting, na metal casting that is pro-duced in a mold obtained by investing (surrounding) anexpendable pattern with a ceramic slurry that is allowed tosolidify. The expendable pattern may consist of wax, plastic, orother material a
11、nd is removed prior to filling the mold withliquid metal.3.1.2 master heat, na quantity of metal processed in asingle furnace or refining vessel at one time in such a manneras to produce the desired composition and properties.3.1.3 sub-heat, na portion of a master heat remeltedwithout additional pro
12、cessing for pouring into castings. Syn-onyms: melt, production heat.1This specification is under the jurisdiction of ASTM Committee F04 onMedical and Surgical Materials and Devices and is the direct responsibility ofSubcommittee F04.12 on Metallurgical Materials.Current edition approved May 15, 2012
13、. Published June 2012. Originallyapproved in 1967. Last previous edition approved in 2007 as F75 075. DOI:10.1520/F0075-12.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, re
14、fer to the standards Document Summary page onthe ASTM website.3Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001, http:/www.sae.org.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www
15、.ansi.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.NOTE 1Terminology section in accordance with Specification A957.4. Ordering Information4.1 Include with inqui
16、ries and orders for material under thisspecification the following information:4.1.1 Quantity (number of product castings or weight ofcasting alloy),4.1.2 ASTM designation and date of issue,4.1.3 Units to be certifiedSI or inch-pound.4.1.4 Form (product casting, shot, bar, ingot),4.1.5 Applicable di
17、mensions or drawing number,4.1.6 Condition (as-cast, hot isostatically pressed (HIP),solution annealed, and so forth),4.1.7 Special tests, if any, and4.1.8 Other requirements.5. Materials and Manufacturing Requirements forProduct Castings5.1 Final thermal processing for castings, if any, shall bespe
18、cified by mutual agreement between the supplier andpurchaser.5.2 Castings shall be free of visible investment shell mate-rial and scale when examined without magnification.5.3 Welding may be used to repair castings as agreed uponbetween supplier and purchaser.5.3.1 Weld repair shall be performed in
19、accordance withwritten procedures by individuals certified to perform thoseprocedures.5.3.2 Weld filler metal conforming to the chemistry of Table1 shall be used when it is needed.5.3.3 Weld repair, if any, shall be performed before finalthermal processing.NOTE 2Under certain circumstances, a weld r
20、epair may act as a stressriser. Therefore, care should be exercised in the location and extent ofweld repair as it relates to regions of the implant where significant stressesmight occur.6. Chemical Requirements6.1 Both product castings and casting alloy shall conform tothe chemical requirements pre
21、scribed in Table 1. The suppliershall not ship material that is outside the limits specified inTable 1.6.1.1 Chemical analysis shall be performed on a represen-tative specimen of a sub heat cast from each master heat usingthe same general foundry procedures used for casting implants.6.1.2 Requiremen
22、ts for the major and minor elementalconstituents are listed in Table 1. Also listed are importantresidual elements. Analysis for elements not listed in Table 1 isnot required to verify compliance with this specification.6.2 Product Analysis:6.2.1 Product analysis tolerances do not broaden the speci-
23、fied heat analysis requirements but cover variations in themeasurement of chemical content between laboratories . Theproduct analysis tolerances shall conform to the producttolerances in Table 2.6.2.2 The product analysis is either for the purpose ofverifying the composition of a heat or manufacturi
24、ng lot or todetermine variations in the composition within the heat.6.2.3 Acceptance or rejection of a heat or manufacturing lotof material may be made by the purchaser on the basis of thisproduct analyses. Product analysis outside the tolerance limitsallowed in Table 2 are cause for rejection of th
25、e product. Areferee analysis may be used if agreed upon by supplier andpurchaser.7. Mechanical Requirements7.1 Tensile Properties for Product Castings:7.1.1 As-cast material shall conform to the mechanicalproperty requirements given in Table 3 when tested in accor-dance with Test Methods E8/E8M.7.1.
26、2 Tension test specimens shall be melted and cast froma sub heat of each master heat by the same general proceduresused in casting the surgical implants or machined from surgicalimplant castings.TABLE 1 Chemical CompositionElementComposition, % (Mass/Mass)min maxChromium 27.00 30.00Molybdenum 5.00 7
27、.00Nickel . 0.50Iron . 0.75Carbon . 0.35Silicon . 1.00Manganese . 1.00Tungsten . 0.20Phosphorous . 0.020Sulfur . 0.010Nitrogen . 0.25Aluminum . 0.10Titanium . 0.10Boron . 0.010CobaltAbalance balanceAApproximately equal to the difference of 100 % and the sum percentage of theother specified elements.
28、 The percentage of the cobalt difference is not required tobe reported.TABLE 2 Product Analysis TolerancesA,BElementTolerance Under the Minimumor Over the Maximum Limit,% (Mass/Mass)CChromium 0.30Molybdenum 0.15Nickel 0.05Iron 0.03Carbon 0.02Silicon 0.05Manganese 0.03Tungsten 0.04Phosphorous 0.005Su
29、lfur 0.003Nitrogen 0.02DAluminum 0.02Titanium 0.02Boron 0.002ASee Test Methods E354.BRefer to AMS Standard 2269 for chemical check analysis limits (exceptnitrogen).CFor elements in which only a maximum percentage is indicated, the “underminimum limit” is not applicable.DRefer to AMS 2248 for chemica
30、l check analysis limits.F751227.1.3 Specimens may be cast, ground, or machined to finaldimensions in accordance with the 0.25 in. (6.35 mm) diameterspecimen in Fig. 8 of Test Methods E8/E8M.7.1.4 Perform at least two tension tests per master heat.Should any of these test pieces not meet the specifie
31、d require-ments, test two additional representative test pieces, in thesame manner, for each failed test piece. The master heat shallbe considered in compliance only if all additional test piecesmeet the specified requirements.7.1.5 Tensile tests results for which any specimen fracturesoutside the g
32、age length shall be considered valid if both theelongation and reduction of area meet the minimum require-ments specified. If either the elongation or reduction of area isless than the minimum requirement, invalidate the specimenand retest. Retest one specimen for each invalidated specimen.7.1.6 If
33、castings are supplied in a heat-treated condition,tensile property requirements shall be agreed upon betweensupplier and purchaser.7.2 Tensile Properties for Casting Alloy:7.2.1 As-cast material shall conform to the mechanicalproperty requirements given in Table 3 when tested in accor-dance with Tes
34、t Methods E8/E8M.7.2.2 Tensionepsis test specimens shall be melted and castfrom a sub heat of each master heat by the same generalprocedures used in casting of the surgical implants7.2.3 Specimens may be cast, ground, or machined to finaldimensions in accordance with the 0.25 in. (6.35 mm) diameters
35、pecimen in Fig. 8 of Test Methods E8/E8M.7.2.4 Perform at least two tension tests per master heat.Should any of these test pieces not meet the specified require-ments, test two additional representative test pieces, in thesame manner, for each failed test piece. The master heat shallbe considered in
36、 compliance only if all additional test piecesmeet the specified requirements.7.2.5 Tensile tests results for which any specimen fracturesoutside the gage length shall be considered valid if both theelongation and reduction of area meet the minimum require-ments specified. If either the elongation o
37、r reduction of area isless than the minimum requirement, invalidate the specimenand retest. Retest one specimen for each invalidated specimen.8. Special Testing for Product Castings8.1 Liquid Penetrant ExaminationSampling plans andacceptance criteria shall be mutually agreed upon by supplierand purc
38、haser. Individual parts should be examined in accor-dance with Test Method E601 or Test Method E165,asappropriate for the surface condition of the casting beingtested.8.2 Radiographic ExaminationSampling plans and accep-tance criteria shall be mutually agreed upon by supplier andpurchaser. Radiograp
39、hic examination shall be in accordancewith Practice F629.8.3 MetallographyThe microstructural requirements andfrequency of examinations shall be mutually agreed upon bysupplier and purchaser. Specimen preparation shall be inaccordance with Guide E3 and Practice E407.8.4 Hardness:8.4.1 Materials conf
40、orming to this specification will typi-cally have a hardness of 25 to 35 HRC in the as-cast condition.The hardness determination shall be performed in accordancewith Test Methods E18.8.4.2 Hardness values are for information only and shall notbe used as criteria for rejection.9. Significance of Nume
41、rical Limits9.1 The following applies to all specified numerical limits inthis specification. To determine conformance to these limits, anobserved or calculated value shall be rounded to the nearestunit in the last right hand digit used in expressing thespecification limit, in accordance with the ro
42、unding method ofPractice E29.10. Certification10.1 The supplier shall provide a certification that thematerial was tested in accordance with this specification andmet all requirements. A report of the test results shall befurnished to the purchaser at the time of shipment.10.1.1 If the supplier and
43、purchaser are one and the same,equivalent internal documentation shall be acceptable in lieu ofcertification.11. Quality Program Requirements11.1 The supplier shall maintain a quality program asdefined in ISO 9001 or similar quality program.12. Keywords12.1 castingssurgical; cobalt alloys (for surgi
44、cal im-plants); cobalt-chromium-molybdenum-metals (for surgicalimplants); cobalt alloysTABLE 3 As-Cast Mechanical RequirementsPropertyUltimate tensile strength, min, MPa (psi) 655 (95 000)Yield strength, (0.2 % offset), min, MPa (psi) 450 (65 000)Elongation,Amin, % 8Reduction of area, min, % 8AElong
45、ation of material 0.063 in. (1.6 mm) or greater in diameter (D) or width (W)shall be measured using a gauge length of 2 in. or 4D or 4W. The gauge lengthmust be reported with the test results. The method for determining elongation ofmaterial under 0.063 in. (1.6 mm) in diameter or thickness may be n
46、egotiated.Alternately, a gauge length corresponding to ISO 6892 may be used when agreedupon between supplier and purchaser. (5.65 times the square root of So, where Sois the original cross-sectional area.)F75123APPENDIXES(Nonmandatory Information)X1. RATIONALEX1.1 The mechanical properties listed in
47、 Table 3 are used toverify the capability of the alloy to produce castings ofacceptable strength and ductility. For consistency of testresults, it is advisable to subject test bars to the sameradiographic and penetrant requirements as will be used for thecastings they represent.X1.2 Cast microstruct
48、ure and mechanical properties aredependent on cross sectional thickness. The mechanical prop-erties measured on as-cast14-in. diameter test bars may not bethe same as those in castings of different cross-sectionalthickness.X1.3 Various heat treatments, including hot isostatic press-ing, solution ann
49、ealing, and sintering, may be used oncobalt-28 chromium-6 molybdenum alloy surgical implantcastings. This specification is not intended to cover the effectsof such processes.X1.4 If castings are straightened, bent or welded, they mayrequire subsequent annealing or special testing per Section 8.X1.5 Because of the wide variety of devices made from thisalloy, 100 % radiographic inspection may not be required.X1.6 The approximate ISO standard equivalent for thismaterial is ISO 5832-4. (Such ISO standards are listed forreference only. Although ISO standards are simil
