1、Designation: F1537 11Standard Specification forWrought Cobalt-28Chromium-6Molybdenum Alloys forSurgical Implants (UNS R31537, UNS R31538, and UNSR31539)1This standard is issued under the fixed designation F1537; the number immediately following the designation indicates the year oforiginal adoption
2、or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope*1.1 This specification covers the chemical, mechanical, andmetallurgical require
3、ments for three wrought cobalt-28chromium-6molybdenum alloys used for surgical implants.The properties specified apply specifically to wrought bar, rod,and wire.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalconversions to SI
4、units that are provided for information onlyand are not considered standard.2. Referenced Documents2.1 ASTM Standards:2E8/E8M Test Methods for Tension Testing of MetallicMaterialsE18 Test Methods for Rockwell Hardness of Metallic Ma-terialsE29 Practice for Using Significant Digits in Test Data toDet
5、ermine Conformance with SpecificationsE112 Test Methods for Determining Average Grain SizeE354 Test Methods for Chemical Analysis of High-Temperature, Electrical, Magnetic, and Other Similar Iron,Nickel, and Cobalt AlloysF75 Specification for Cobalt-28 Chromium-6 MolybdenumAlloy Castings and Casting
6、 Alloy for Surgical Implants(UNS R30075)F799 Specification for Cobalt-28Chromium-6MolybdenumAlloy Forgings for Surgical Implants (UNS R31537,R31538, R31539)2.2 Aerospace Material Specifications:3AMS 2248 Chemical Check Analysis Limits, Corrosionand Heat Resistant Steels and Alloys, Maraging and Othe
7、rHighly-Alloyed Steels, and Iron AlloysAMS 2269 Chemical Check Analysis Limits, Nickel,Nickel Alloys and Cobalt AlloysAMS 2630 Inspection, Ultrasonic Product over 0.5 Inch(12.7 mm) Thick2.3 ISO Standards:4ISO 583212 Implants for SurgeryMetallic MaterialsPart 12: Wrought Cobalt-Chromium-Molybdenum Al
8、loyISO 6892 Metallic Materials Tensile Testing at AmbientTemperatureISO 9001 Quality Management SystemsRequirements3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 lotthe total number of mill products produced fromthe same melt heat under the same conditions at essentially thes
9、ame time.4. Ordering Information4.1 Inquiries and orders for material under this specificationshall include the following information:4.1.1 Quantity,4.1.2 ASTM designation, alloy number, and date of issue,4.1.3 Mechanical properties (See Section 7),4.1.4 Form (bar, rod or wire),4.1.5 Applicable dime
10、nsions including size, thickness,width, and length (exact, random, or multiples) or drawingnumber,4.1.6 Condition (See Section 5),4.1.7 Special tests (if any), and4.1.8 Other requirements.1This specification is under the jurisdiction of ASTM Committee F04 onMedical and Surgical Materials and Devices
11、 and is the direct responsibility ofSubcommittee F04.12 on Metallurgical Materials.Current edition approved Nov. 15, 2011. Published December 2011. Originallyapproved in 1994. Last previous edition approved in 2008 as F1537 08. DOI:10.1520/F1537-11.2For referenced ASTM standards, visit the ASTM webs
12、ite, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Available from Society of Automotive Engineers (SAE), 400 CommonwealthDr., Warrendale, PA 15096-0001, http:/www
13、.sae.org.4Available from American National Standards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.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 19428-295
14、9, United States.5. Materials and Manufacture5.1 Product shall be furnished as specified below:5.1.1 The annealed condition is typically supplied as a hotrolled and annealed product.5.1.2 The hot worked condition is typically supplied as a hotrolled and unannealed product.5.1.3 The warm worked condi
15、tion is typically supplied as athermomechanically processed product to achieve a strain-hardened structure.6. Chemical Requirements6.1 The cobalt-28chromium-6molybdenum alloys shall con-form to the chemical requirements prescribed in Table 1. Thesupplier shall not ship material that is outside the l
16、imitsspecified in Table 1 for the applicable alloy.6.1.1 Requirements 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 A
17、nalysisThe product analysis is either for thepurpose of verifying the composition of a heat or lot or todetermine variations in the composition within the heat.6.2.1 Acceptance or rejection of a heat or lot of materialmay be made by the purchaser on the basis of this productanalysis.6.2.2 Product an
18、alysis tolerances do not broaden the speci-fied heat analysis requirements but cover variations betweenlaboratories in the measurement of chemical content. Productanalysis limits shall be as specified in Table 2.7. Mechanical Requirements7.1 Tensile Properties:7.1.1 Perform at least two tension test
19、s from each lot.Should any of these test pieces not meet the specified require-ments, test two additional test pieces representative of the samelot, in the same manner, for each failed test piece. The lot shallbe considered in compliance only if all additional test piecesmeet the specified requireme
20、nts.7.1.2 Tensile test results for which any specimen fracturesoutside the gauge length shall be considered acceptable, if boththe elongation and reduction of area meet the minimumrequirements specified. Refer to subsections 7.11.4 and 7.11.5of Test Methods E8/E8M.7.1.3 The mechanical properties of
21、test specimens shallconform to the requirements specified in Table 3.7.2 Hardness:7.2.1 Hardness values shall be determined in accordancewith Test Methods E18.7.2.2 Hardness values are for information only and shall notbe used as a basis for rejection.8. Microstructure Requirements8.1 Bar, rod, and
22、wire conforming to this specification shallhave a homogeneous microstructure with an average grain sizeof ASTM No. 5 or finer when measured in accordance withTest Methods E112.9. Ultrasonic Inspection9.1 For finished thicknesses 0.250 in. (6.35 mm) andgreater, inspection shall be per AMS 2630 Class
23、A1. Equiva-lent test methods may be substituted when agreed to bypurchaser and supplier.AMS 2630 indicates a minimum size of0.500 in. (12.7 mm). The use of this specification to aTABLE 1 Chemical CompositionComposition % (mass/mass)Element Alloy 1UNS R31537(Low Carbon)Alloy 2UNS R31538(High Carbon)A
24、lloy 3UNS R31539(DispersionStrengthened)min max min max min maxCarbon 0.14 0.15 0.35 0.14Aluminum 0.30 1.00Lanthanum 0.03 0.20Chromium 26.0 30.0 26.0 30.0 26.0 30.0Molybdenum 5.0 7.0 5.0 7.0 5.0 7.0Nickel 1.0 1.0 1.0Iron 0.75 0.75 0.75Silicon 1.0 1.0 1.0Manganese 1.0 1.0 1.0Nitrogen 0.25 0.25 0.25Co
25、baltABalance Balance BalanceAApproximately equal to the difference of 100 % and the sum percentage of theother specified elements. The percentage of cobalt difference is not required to bereported.TABLE 2 Product Analysis TolerancesA,BElement Permissible Variation Under the MinimumLimit or Over the
26、Maximum Limit, % (mass/mass)CCarbon 0.02Aluminum # 0.50 0.05Aluminum0.50upto1.00 0.10Lanthanum 0.01Chromium 0.30Molybdenum 0.15Nickel 0.05Iron 0.03Silicon 0.05Manganese 0.03NitrogenD0.02ASee Test Methods E354.BRefer to AMS 2269 for chemical check analysis limits (except nitrogen).CFor elements in wh
27、ich only a maximum percentage is indicated, the “underminimum limit” is not applicable.DRefer to AMS 2248.TABLE 3 Mechanical RequirementsConditionUltimateTensileStrengthmin, psi(MPa)YieldStrength(0.2 %offset),min, psi(MPa)ElongationAmin, %Reductionin Areamin, %HardnessHRC,TypicalAnnealed 130 000(897
28、)75 000(517)20 20 25HotWorked145 000(1000)101 000(700)12 12 28WarmWorked170 000(1172)120 000(827)12 12 35AElongation of material 0.062 in. (1.575 mm) or greater in diameter or thicknessshall be measured using a gauge length of 2 in. or 4D or 4W. The gauge lengthmust be reported with the test results
29、. The method for determining elongation ofmaterial under 0.062 in. (1.57 mm) in diameter or thickness may be negotiated.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 se
30、ctional area).F1537 112minimum size of 0.250 in. (6.35 mm) is done with agreementof producer and user members of the committee.9.2 For finished thicknesses less than 0.250 in. (6.35 mm)and for shape bar that cannot be inspected at finish, interme-diate size bars or billets shall be ultrasonically in
31、spected perAMS 2630 Class A1 or as agreed upon by purchaser andsupplier.10. Significance of Numerical Limits10.1 The following applies to all specified numerical limitsin this specification. To determine conformance to these limits,an observed or calculated value shall be rounded to the nearestunit
32、in the last right hand digit used in expressing thespecification limit, in accordance with the Rounding Method ofPractice E29.11. Certification11.1 The supplier shall provide a certification that thematerial was manufactured and tested in accordance with therequirements of this specification. A repo
33、rt of the test resultsshall be furnished to the purchaser at the time of shipment.12. Quality Program Requirements12.1 The alloy supplier shall maintain a quality program orquality management system, such as ISO 9001.13. Keywords13.1 cobalt alloys (for surgical implants); cobalt-28chromium-6molybden
34、um; metals (for surgical implants)APPENDIXES(Nonmandatory Information)X1. RATIONALEX1.1 The purpose of this specification is to characterizecomposition and properties to ensure consistency in wroughtcobalt-28chromium-6molybdenum bar, rod, and wire used inthe manufacturing of medical devices.X1.2 The
35、 carbon content of commercially available F1537barstock varies to meet specific customer needs. The chemicalcomposition was expanded into low and high carbon alloys(Alloys 1 and 2 in Table 1). Alloy 2 contains a greater volumefraction of carbides compared to Alloy 1.X1.3 Alloy 3 was added in Table 1
36、 since bar, rod, and wireproduced with this composition meet the current ASTM F1537requirements. Alloy 3 is a dispersion-strengthened alloy con-taining fine aluminum-lanthanum oxides/nitrides.5,6X1.4 The minimum mechanical properties of wrought bar,rod, and wire conforming to this specification are
37、superior tothe minimum mechanical properties of Specification F75material in the as-cast condition.X1.5 Some complex metallic phases, such as carbides,oxides, or carbonitrides, or combinations thereof, may bepresent in the microstructure of this alloy.X1.6 ISO standards are listed for reference only
38、. Althoughthe ISO 583212 standard listed in Section 2 is similar to thecorresponding ASTM standard, they are not identical. Use ofthe ISO standard instead of the preferred ASTM standard maybe agreed upon between purchaser and supplier. The mechani-cal properties of warm-worked condition material, su
39、bsection5.1.3, of this specification are equivalent to the ISO 583212cold-worked condition.X1.7 Wrought material, typically hot-worked and unan-nealed with a surface suitable for forging, shall be fabricatedand supplied in accordance with this specification when used asforging stock in the manufactu
40、re of forgings in accordancewith Specification F799.X2. BIOCOMPATIBILITYX2.1 The alloy compositions covered by this specificationhave been employed successfully in human implant applica-tions in contact with soft tissue and bone for over a decade(reference 510k #K852964 for Alloy 3, which has been u
41、sedsince 1985).X2.2 No known surgical implant material has ever beenshown to be completely free of adverse reactions in the humanbody. Long term clinical experience of the use of the materialreferred to in this specification, however, has shown that anacceptable level of biological response can be e
42、xpected, if thematerial is used in appropriate applications.5Wang, K. K., Gustavson, L. J., and Dumbleton, J. H., U.S. Patent #4,668,290,“Dispersion Strengthened Cobalt-Chromium-Molybdenum Alloy Produced By GasAtomization”, Filed August 13, 1985, Issued May 26, 1987.6Wang, K. K., Gustavson, L. J., a
43、nd Dumbleton, J. H., “The Development of aNew Dispersion Strengthened Vitallium Alloy for Medical Implants”, ModernDevelopments in Powder Metallurgy, Vol 20, 1988, pp. 361375, Metal PowderIndustries Federation, 105 College Road East, Princeton, NJ 08540-6692.F1537 113SUMMARY OF CHANGESCommittee F04
44、has identified the location of selected changes to this standard since the last issue (F1537 08)that may impact the use of this standard. (Approved Nov. 15, 2011.)(1) Revised section on ultrasonic inspection to make it explicitwith regards to specification, inspection type, and sizes. Thissection cl
45、early defines how ultrasonic inspection will beperformed on small sizes and special shapes.ASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this standard are expressly advised that determination
46、 of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years andif not revised, either reapproved or withdraw
47、n. Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee, which you may attend. If you feel that your co
48、mments have not received a fair hearing you shouldmake your views known to the ASTM Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single o
49、r multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the ASTM website (www.astm.org/COPYRIGHT/).F1537 114
