1、Designation: F 138 08Standard Specification forWrought 18Chromium-14Nickel-2.5Molybdenum StainlessSteel Bar and Wire for Surgical Implants (UNS S31673)1This standard is issued under the fixed designation F 138; the number immediately following the designation indicates the year oforiginal adoption o
2、r, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.This standard has been approved for use by agencies of the Department of Defense.1. Scope
3、*1.1 This specification covers the chemical, mechanical, andmetallurgical requirements for wrought 18chromium-14nickel-2.5molybdenum stainless steel bar and wire used for themanufacture of surgical implants.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in
4、parentheses are mathematicalconversions to SI units that are provided for information onlyand are not considered standard.2. Referenced Documents2.1 ASTM Standards:2A 262 Practices for Detecting Susceptibility to Intergranu-lar Attack in Austenitic Stainless SteelsA 484/A 484M Specification for Gene
5、ral Requirements forStainless Steel Bars, Billets, and ForgingsA 555/A 555M Specification for General Requirements forStainless Steel Wire and Wire RodsA 751 Test Methods, Practices, and Terminology forChemical Analysis of Steel ProductsE8 Test Methods for Tension Testing of Metallic MaterialsE8M Te
6、st Methods for Tension Testing of Metallic Mate-rials Metric3E10 Test Method for Brinell Hardness of Metallic Materi-alsE18 Test Methods for Rockwell Hardness of MetallicMaterialsE29 Practice for Using Significant Digits in Test Data toDetermine Conformance with SpecificationsE45 Test Methods for De
7、termining the Inclusion Contentof SteelE112 Test Methods for Determining Average Grain SizeE 354 Test Methods for Chemical Analysis of High-Temperature, Electrical, Magnetic, and Other Similar Iron,Nickel, and Cobalt AlloysE 407 Practice for Microetching Metals and AlloysF 981 Practice for Assessmen
8、t of Compatibility of Bioma-terials for Surgical Implants with Respect to Effect ofMaterials on Muscle and BoneF 1350 Specification for Wrought 18Chromium-14Nickel-2.5Molybdenum Stainless Steel Surgical Fixation Wire(UNS S31673)2.2 ISO Standards:4ISO 58321 Implants for SurgeryMetallic MaterialsPart
9、1:Wrought Stainless SteelISO 6892 Metallic MaterialsTensile TestingISO 9001 Quality Management SystemsRequirements2.3 ASQ Standard:5ASQ C1 Specification of General Requirements for a Qual-ity Program3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 bar, nrounds, flats, or other
10、shapes from 0.1875 in.(4.76 mm) to 4 in. (101.60 mm) in diameter or thickness.(Other sizes and shapes by special order.)3.1.2 fine wire, nwire as described in 3.1.5, less than0.063 in. (1.60 mm) in diameter or thickness.3.1.3 forging bar, nbar as described in 3.1.1, used for theproduction of forging
11、s, may be furnished in the hot workedcondition.3.1.4 lot, nthe total number of mill products producedfrom the same melt heat under the same conditions at essen-tially the same time.3.1.5 wire, nrounds, flats or other shapes less than 0.1875in. (4.76 mm) in diameter or thickness.1This specification i
12、s 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 1, 2008. Published May 2008. Originallyapproved in 1971. Last previous edition approved in 2003 a
13、s F 138 03.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn.4Available from American National Stand
14、ards Institute (ANSI), 25 W. 43rd St.,4th Floor, New York, NY 10036, http:/www.ansi.org.5Available from American Society for Quality (ASQ), 600 N. Plankinton Ave.,Milwaukee, WI 53203, http:/www.asq.org.1*A Summary of Changes section appears at the end of this standard.Copyright ASTM International, 1
15、00 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.4. General Requirements for Delivery4.1 In addition to the requirements of this specification, allrequirements of the current editions of Specifications A 484/A 484M and A 555/A 555M shall apply.4.2 In the case where
16、a conflict exists between this specifi-cation and those listed in 2.1 and 2.2, this specification shalltake precedence.5. Ordering Information5.1 Inquiries and orders for material under this specificationshall include the following information:5.1.1 Quantity (weight or number of pieces),5.1.2 ASTM d
17、esignation and date of issue,5.1.3 Form (bar, wire, fine wire),5.1.4 Condition (see 6.1),5.1.5 Mechanical properties (if applicable, for special con-ditions),5.1.6 Finish (see 6.2),5.1.7 Applicable dimensions including size, thickness,width, and length (exact, random or multiples) or drawingnumber,5
18、.1.8 Special tests, if any, and5.1.9 Other requirements.6. Materials and Manufacture6.1 Condition:6.1.1 Bar and wire shall be furnished, as specified, in the hotworked, annealed, cold worked, or extra hard condition (seeTable 1).6.1.2 Fine wire shall be furnished, as specified, in the colddrawn cond
19、ition (see Table 2).6.2 Finish:6.2.1 Types of finish available for bar and wire products arecold drawn, pickled, ground, ground and polished, or asspecified in the purchase order.6.2.2 Types of finish available for fine wire products aredescaled or pickled, abrasive-blasted, cold drawn, ground,groun
20、d and polished, or as specified in the purchase order.7. Chemical Requirements7.1 The heat analysis shall conform to the requirements asto chemical composition specified in Table 3.7.1.1 The compositional requirement shall meet the follow-ing:%Cr1 3.3 3 %Mo$26.0 (1)7.1.2 Requirements for the major a
21、nd minor elementalconstituents are listed in Table 3. Also listed are importantresidual elements. Analysis for elements not listed in Table 3 isnot required to certify compliance with this specification.7.1.3 Methods and practices relating to chemical analysisrequired by this specification shall be
22、in accordance with TestMethods, Practices, and Terminology A 751.7.2 Product AnalysisProduct analysis tolerances do notbroaden the specified heat analysis requirements, but covervariations between laboratories in the measurement of chemi-cal content. The supplier shall not ship material that is outs
23、idethe limits specified in Table 3. Product analysis limits shall beas specified in Table 4.7.2.1 The product analysis is either for the purpose ofverifying the composition of a heat or manufacturing lot or todetermine variations in the composition within the heat.7.2.2 Acceptance or rejection of a
24、heat or lot of materialmay be made by the purchaser on the basis of this productanalysis.7.2.3 Methods and practices relating to chemical analysisrequired by this specification shall be in accordance with TestMethods E 354.8. Metallurgical Requirements8.1 The material shall exhibit no delta ferrite,
25、 chi, or sigmaphases when it is examined metallographically at 1003 mag-nification when etched in accordance with Practice E 407.8.2 The microcleanliness of the steel as determined byMethod A of Test Methods E45, except using Plate I-r, onrepresentative billet or bar samples from the heat shall note
26、xceed the following:InclusionTypeA(Sulfide)B(Alumina)C(Silicate)D(Globular Ox-ides)Thin 1.5 1.5 1.5 1.5Heavy 1.0 1.0 1.0 1.09. Mechanical Properties9.1 Tensile Properties:9.1.1 Tensile properties shall be determined in accordancewith Test Methods E8or E8M.9.1.2 Material shall conform to the appropri
27、ate require-ments as to mechanical properties specified in Table 1 andTable 2.9.1.3 The level of mechanical properties for material inconditions other than those included in Table 1 and Table 2,shall be specified in the purchase order.9.1.4 Bar and wire in the cold worked condition can besupplied to
28、 a higher tensile strength and corresponding lowerelongation as specified on the purchase order.TABLE 1 Mechanical Requirements, Bar and WireCondition Diameter or Thickness, in. (mm)Ultimate TensileStrength, min, psi(MPa)Yield Strength (0.2 %offset), min, psi (MPa)ElongationAin4D or 4W,min, %Brinell
29、BHardness, max,HBHot workedCall 250Annealed 0.063 and over (1.60) 71 000 (490) 27 500 (190) 40 .Cold worked 0.063 to 1.500 (1.60 to 38.1) 125 000 (860) 100 000 (690) 12 .Extra-hard 0.063 to 0.250 (1.60 to 6.35) 196 000 (1350) . . .AThe gage length must be reported with the test results. 4D =43 diame
30、ter; 4W =43 width. Alternatively, a gage length corresponding to Test Methods E8MorISO 6892 may be used when agreed upon between supplier and purchaser. (5.65 times the square root of So, where So is the original cross sectional area).B29-kN (3000-kgf) load.CTypically supplied as hot rolled bar for
31、forging applications.F1380829.1.5 Fine wire in the cold drawn condition can be suppliedto a higher tensile strength and corresponding lower elongationas specified on the purchase order.9.2 Hardness:9.2.1 Hardness values shall be determined in accordancewith Test Method E10or Test Methods E18.9.2.2 W
32、hen desired, hardness limits may be specified by thepurchaser. Hardness determinations shall be made on theproduct cross section, midway between the center and surface,if cross section is adequate.9.2.3 Hardness values are for information only and shall notbe used as a basis for rejection.9.3 Number
33、 of Tests:9.3.1 Perform at least one tension test from each lot. Shouldany of the test pieces not meet the specified requirements, testtwo additional test pieces representative of the same lot, in thesame manner, for each failed test piece. The lot shall beconsidered in compliance only if all additi
34、onal test pieces meetthe specified requirements.9.3.2 Tensile test results for which any specimen fracturesoutside the gage length shall be considered acceptable, if theelongation meets the minimum requirement specified. Refer toTest Methods E 8 and section 7.11.4 of Test Methods E8M.Ifthe elongatio
35、n is less than the minimum requirement, discardthe test and retest. Retest one specimen for each specimen thatdid not meet the minimum requirements.10. Special Tests10.1 Bar, forging bar, wire, and fine wire conforming to thisspecification shall be capable of passing the intergranularcorrosion susce
36、ptibility test in accordance with Practice E ofPractices A 262.10.1.1 Samples in the hot worked condition shall be an-nealed prior to Practice E of Practices A 262, sensitization heattreatment.10.2 Bar, forging bar, wire, and fine wire conforming to thisspecification shall have a grain size of ASTM
37、No. 5 or finerwhen measured in accordance with Test Methods E112.10.2.1 It is preferred that samples for grain size determina-tion be selected after the hot working operation or after thefinal annealing operation prior to the final cold workingoperation.10.2.2 If samples are selected after a final c
38、old workingoperation, specimens shall be tested in accordance with TestMethods E112or as agreed to between supplier and purchaser.10.3 Finished round bar greater than 0.250 in. (6.35 mm)diameter shall be inspected using ultrasonic or equivalent testmethods. Billet shall also be ultrasonically tested
39、 prior to beinghot rolled and should be free of internal defects. Acceptancecriteria shall be agreed to between purchaser and supplier.10.4 Any other special requirements shall be specified bythe purchaser.11. Significance of Numerical Limits11.1 The following applies to all specified numerical limi
40、tsin this specification. To determine conformance to these limits,an observed or calculated value shall be rounded to the nearestunit in the last right hand digit used in expressing thespecification limit, in accordance with the rounding method ofPractice E29.12. Certification12.1 The supplier shall
41、 provide a certification that thematerial meets the requirements of this specification. A reportof the test results shall be furnished to the purchaser at the timeof shipment.13. Quality Program Requirements13.1 The supplier shall maintain a quality program, such asdefined in ASQ C1, ISO 9001, or si
42、milar.TABLE 2 Mechanical Requirements, Fine WireAConditionBDiameter, in. (mm)UltimateCTensile Strength, psi(MPa)Elongation in 10 in. (254mm), min, %Cold drawn under 0.063(1.60)125 000 to 150 000(860 to 1035)5AAnnealed fine wire requirements are covered in Specification F 1350.BRecommended crosshead
43、speed for cold drawn fine wire is 5 in./min (2.0 mm/s).CCold drawn wire may be ordered to tensile strengths up to 300 000 psi (2070 MPa) with lower elongation as determined by purchaser and supplier.TABLE 3 Chemical Requirements, Heat AnalysisElementComposition, %(mass/mass)Carbon 0.030 maxManganese
44、 2.00 maxPhosphorous 0.025 maxSulfur 0.010 maxSilicon 0.75 maxChromiumA17.00 to 19.00Nickel 13.00 to 15.00MolybdenumA2.25 to 3.00Nitrogen 0.10 maxCopper 0.50 maxIronBbalanceAThe compositional requirement shall meet the following:%Cr+3.33 %Mo$ 26.0.BThe percentage of iron content by difference is not
45、 required to be determinedor certified.TABLE 4 Product Analysis ToleranceAElementTolerance Under theMinimum or Over theMaximum Limit, %(mass/mass)BCarbon 0.005Manganese 0.04Phosphorous 0.005Sulfur 0.005Silicon 0.05Chromium 0.20Nickel 0.15Molybdenum 0.10Nitrogen 0.01Copper 0.03ARefer to Specification
46、 A 555/A 555M.BUnder minimum limit not applicable for elements where only a maximumpercentage is indicated.F13808314. Keywords14.1 metals (for surgical implants); stainless steel; surgicalapplications wire; surgical implantsAPPENDIXES(Nonmandatory Information)X1. RATIONALEX1.1 The primary reason for
47、 this specification is to char-acterize composition and properties to ensure consistency inthe starting material used directly, or as modified by forging, inthe manufacturing of medical devices.X1.2 This low carbon alloy is selected to provide an extrameasure of assurance that the material will be f
48、ree fromsusceptibility to intergranular corrosion.X1.3 There is a general consensus that a homogeneousmetallurgical structure will be superior with respect to corro-sion and fatigue resistance. Based upon this, metallurgicalrequirements include fine-grained austenitic structure free offerrite, with
49、low micro-inclusion content, and capability ofpassing an intergranular corrosion susceptibility test.X1.4 Acceptable metal conditions include hot worked,annealed, and all cold worked conditions, the choice dependentupon the implant design and application.NOTE X1.1Exposure to temperatures above 800F (425C) duringfabrication may impair corrosion resistance unless such exposure isfollowed by a solution annealing treatment.X1.5 Upper composition limits for nickel and lower com-position limits for molybdenum have been changed in order tomeet the latest requirements spec
