1、Designation: F 1160 05Standard Test Method forShear and Bending Fatigue Testing of Calcium Phosphateand Metallic Medical and Composite Calcium Phosphate/Metallic Coatings1This standard is issued under the fixed designation F 1160; the number immediately following the designation indicates the year o
2、foriginal adoption or, 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.1. Scope1.1 This test method covers the procedure for determiningthe
3、shear and bending fatigue performance of calcium phos-phate coatings and of porous and nonporous metallic coatingsand for determining the bending fatigue performance ofmetallic coatings oversprayed with calcium phosphate. Thistest method has been established based on plasma-sprayedtitanium and plasm
4、a-sprayed hydroxylapatite coatings. Theefficacy of this test method for other coatings has not beenestablished. In the shear fatigue mode, this test methodevaluates the adhesive and cohesive properties of the coatingon a metallic substrate. In the bending fatigue mode, this testmethod evaluates both
5、 the adhesion of the coating as well asthe effects that the coating may have on the substrate material.These methods are limited to testing in air at ambient tempera-ture. These test methods are not intended for application infatigue tests of components or devices; however, the testmethod which most
6、 closely replicates the actual loadingconfiguration is preferred.1.2 The values stated in SI units are to be regarded as thestandard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is theresponsibility of the user of this standard to estab
7、lish appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E6 Terminology Relating to Methods of Mechanical Test-ingE 206 Definitions of Terms Relating to Fatigue Testing andthe Statistical Analysis
8、 of Fatigue Data3E 466 Practice for Conducting Force Controlled ConstantAmplitude Axial Fatigue Tests of Metallic MaterialsE 467 Practice for Verification of Constant Amplitude Dy-namic Forces in an Axial Load Fatigue Testing SystemE 468 Practice for Presentation of Constant Amplitude Fa-tigue Test
9、Results for Metallic MaterialsE 1012 Practice for Verification of Specimen AlignmentUnder Tensile Loading3. Definitions3.1 The definitions of terms relating to shear and fatiguetesting appearing in Terminology E6shall be considered asapplying to the terms used in this test method.4. Summary of Test
10、Method4.1 Shear Fatigue Testing:4.1.1 The intent of the shear fatigue test is to determine theadhesive or cohesive strength, or both, of the coating.4.1.2 This test method is designed to allow the coating tofail at either the coating/substrate interface, within the coating,or at the glue/coating int
11、erface between the coating and theadhesive bonding agent used to transmit the load to the coating.4.2 Bending Fatigue Testing:4.2.1 The primary intent of the bending fatigue test is toquantify the effect that the coating has on the substrate it isapplied to. Secondarily, it may be used to provide a
12、subjectiveevaluation of coating adhesion, (that is, spalling resistance,cracking resistance, and so forth).4.2.2 This test method is designed to first provide a substratefatigue strength to serve as a baseline to assess the effects of thecoating on the resulting fatigue strength of the system.5. Sig
13、nificance and Use5.1 The shear and bending fatigue tests are used to deter-mine the effect of variations in material, geometry, surfacecondition, stress, and so forth, on the fatigue resistance of1This test method is under the jurisdiction of ASTM Committee F04 on Medicaland Surgical Materials and D
14、evices and is the direct responsibility of SubcommitteeF04.15 on Materials Test Methods.Current edition approved April 1, 2005. Published April 2005. Originallyapproved in 1991. Last previous edition approved in 2000 as F 1160 00e1.2For referenced ASTM standards, visit the ASTM website, www.astm.org
15、, 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.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.coa
16、ted metallic materials subjected to direct stress for up to 107cycles. These tests may be used as a relative guide to theselection of coated materials for service under condition ofrepeated stress.5.2 In order that such basic fatigue data be comparable,reproducible, and can be correlated among labor
17、atories, it isessential that uniform fatigue practices be established.5.3 The results of the fatigue test may be used for basicmaterial property design. Actual components should not betested using these test methods.6. Equipment Characteristics6.1 Equipment characteristics shall be in accordance wit
18、hPractice E 466, Section 7. See also Practices E 467 and E 1012and Definitions E 206.6.2 Shear Fatigue Test Grips:6.2.1 GeneralVarious types of grips may be used totransmit the load to the specimens by the testing machine. Toensure axial shear stress, it is important that the specimen axiscoincide w
19、ith the centerline of the heads of the testing machineand that the coating test plane be parallel to the axial load. Anydeparture from this requirement (that is, any eccentric loading)will introduce bending stresses that are not included in theusual stress calculation (force/cross-sectional area).6.
20、2.2 A drawing of a typical gripping device for the testassembly is shown in Fig. 1.6.2.3 Fig. 2 shows a drawing of the adaptor to mate theshear fixture to the tensile machine6.2.4 Figs. 3 and 4 show a schematics of the test setup.6.3 Bending Fatigue Test GripsThere are a variety oftesting machines t
21、hat may be employed for this test (that is,rotating beam fatigue machines and axial fatigue machines).The gripping method for each type of equipment shall bedetermined by either the manufacturer of that equipment(rotating beam machines) or the user.7. Adhesive Bonding Materials7.1 Adhesive Bonding A
22、gentA polymeric adhesive bond-ing agent in film form, or filled viscous adhesive cement, shallbe identified and shall meet the following requirements.7.1.1 The bonding agent shall be capable of bonding thecoating on the test specimen components with an adhesiveshear strength that is at least 34.5 MP
23、a (5000 psi) or as great asthe minimum required adhesion or cohesion strength of thecoating, whichever is greater.7.1.2 In instances where coating porosity extends to thecoating/substrate interface, the bonding agent shall be suffi-ciently viscous and application to the coating sufficientlydetailed,
24、 to ensure that it will not penetrate through the coatingto the substrate. The FM 1000Adhesive Film4with a thicknessof 0.25 mm (0.01 in.) has proven satisfactory for this testmethod.7.1.3 If a material other than FM 1000 is used, or thecondition of the FM 1000 is unknown, it must be tested toestabli
25、sh its equivalence to fresh FM 1000. Testing should beperformed without the presence of the coating to establish theperformance of the adhesive.4The sole source of supply of the apparatus known to the committee at this timeis Cytec Engineered Materials, Inc., 1300 Revolution St., Havre de Grace, MD2
26、1078. If you are aware of alternative suppliers, please provide this information toASTM International Headquarters. Your comments will receive careful consider-ation at a meeting of the responsible technical committee,1which you may attend.FIG. 1 Gripping Device for Shear TestingFIG. 2 Adaptor to Ma
27、te the Gripping Device to the TensileMachineFIG. 3 Schematic of the Shear Test SetupF11600528. Test Specimen8.1 Shear Fatigue Specimen for Calcium Phosphate andMetallic Coatings Only:8.1.1 The recommended shear test specimen and setup isillustrated in Figs. 3 and 4, respectively. A complete assemble
28、dtest assembly consists of two solid pieces, one with a coatedsurface and the other with an uncoated surface. The uncoatedsurface may be roughened to aid in the adhesion of theadhesive bonding agent.8.1.2 The cross-sectional area of the substrate upon whichthe coating is applied shall be a nominal 2
29、.85 cm2(0.44 in.2).When specimens of another cross-sectional area are used, thedata must be demonstrated to be equivalent to the resultsproduced using the 2.85-cm2standard cross-sectional area andthe specimen size should be reported.8.2 Bending Fatigue Specimen for Calcium Phosphate,Metallic, and Ca
30、lcium Phosphate-Metallic Composite Coat-ings:8.2.1 The type of specimen used will depend upon theobjective of the test program, the type of equipment, theequipment capacity, and the form in which the material isavailable. However, the design must meet certain generalcriteria as follows:8.2.1.1 The d
31、esign of the specimen should be such that ifspecimen failure should occur, it should occur in the testsection (reduced area as shown in Figs. 5-8).8.2.1.2 Specimens using a flat tapered beam configurationshould be designed such that a constant surface stress exists inthe test section when the specim
32、en is constrained at one endand point loaded perpendicular to the beam axis at the otherend (that is, cantilever loading).8.2.1.3 Rotating beam specimens may have unique dimen-sions, depending upon the type of machine used. Appropriatemanufacturers specifications for these specimens should beused.8.
33、3 Specimen Coating Preparation:8.3.1 Coatings may be applied by any one of a number oftechniques. All test specimens for coating characterizationshall be prepared from indicative coating lots, using productionfeedstock lots and be coated on the same equipment used foractual implants. The coating sho
34、uld consist of a layer which ismechanically or chemically attached and covers the surface.8.3.2 Coatings should be applied as follows:8.3.2.1 For the shear fatigue specimens, the coating shouldbe applied to the 19.05-mm (0.75-in.) diameter face only (seeFig. 3).8.3.2.2 For the bending fatigue specim
35、ens, the coatingshould be applied to the reduced section only, with theexception of the constant stress specimen which should havecoating in the entire region of constant stress (see Figs. 5-9).8.3.3 All thermal treatments normally performed on thedevices should be performed on the test specimens.FI
36、G. 4 Drawing of the Recommended Shear Test SpecimenAssemblyFIG. 5 Bending Fatigue Specimen With Tangentially BlendingFillets Between the Test Section and the Ends for Rotating Beamor Axial LoadingFIG. 6 Specimens With a Continuous Radius Between the Endsfor Rotating Beam or Axial loadingFIG. 7 Speci
37、mens With Tangentially Blending Fillets Between theUniform Test Section and the Ends for Axial LoadingFIG. 8 Specimens With a Continuous Radius Between the Endsfor Axial LoadingFIG. 9 Tapered Beam Configuration for Bend TestingF11600538.3.4 If used, passivation and sterilization techniques shouldbe
38、consistent with those used for actual devices.8.3.5 InspectionBefore testing, visual inspections shouldbe performed on 100 % of the test specimens. Non-uniformcoating density shall be cause for specimen rejection. For theshear fatigue specimen, lack of coating on the coated face shallbe cause for sp
39、ecimen rejection. For the bending fatiguespecimen, lack of coating in highly stressed regions shall because for specimen rejection.9. Procedure9.1 The number of specimens required for testing, as well asthe test methods in which the fatigue data may be interpreted,can vary. Several test methods are
40、referenced in this testmethod.5,6,79.2 The type of specimen used will depend upon theobjective of the test program, the type of equipment available,the equipment capacity, and the form in which the material isavailable. The specimen chosen should come as close tomatching the intended application as
41、possible.9.3 The test frequency used shall not exceed 170 Hz.9.4 Shear Fatigue Specimens:9.4.1 Curing the AdhesiveThe test results achieved aregreatly dependent upon the adhesive used and the way in whichit is cured. One suggested adhesive is FM 1000 having athickness of 0.25 mm (0.01 in.). This mat
42、erial has successfullybeen cured using the following cycle:9.4.1.1 Align the adhesive with the surface of the coating,taking precautions to align the adhesive in the center of thecoating.9.4.1.2 Apply a constant force using a calibrated hightemperature spring, resulting in a stress of 0.138 MPa (20
43、psi)between the coating and the opposing device that will test thecoating.9.4.1.2.1 Care must be taken to maintain alignment of thecoating and the matching counterface during the test.9.4.1.3 Place the assembly in an oven and heat at 176C for23 h.9.4.1.3.1 The exact amount of time necessary to cure
44、theadhesive will need to be determined by each user, as oventemperature may vary with load size and oven type. It issuggested that the curing cycle be optimized first without thecoating present.9.4.1.4 Remove the cured assembly from the oven andallow it to cool to room temperature.9.4.1.5 Remove all
45、 excess adhesive which has protrudedfrom the coated surface. This process must not compromise theintegrity of the sample.9.4.2 Place the specimen assembly in the grips so that thelong axis of the specimen is perpendicular to the direction ofthe applied shear load through the centerline of the gripas
46、sembly (see Fig. 3).9.4.3 Specimens for which the adhesive has penetrated tothe substrate shall be discarded and the results not included inthe analysis and report.9.5 Bending Fatigue Specimens:9.5.1 Appropriate testing of the uncoated substrate material,upon which the coating will be applied, shoul
47、d be performed toestablish a baseline from which to assess the effect of thecoating.9.5.1.1 The baseline test specimens may or may not begrit-blasted depending upon the objective of the test. In eitherevent, the surface roughness should be reported.9.5.1.2 For composite calcium phosphate-metallic co
48、atings,additional baseline testing of specimens with only the metalliccoating should also be preformed to allow an assessment of theeffects of each coating.9.5.2 When mounting the specimen, alignment is crucial.Factors such as poorly machined specimens and misalignmentof machine parts might result i
49、n excessive vibration leading toerroneous results.9.5.3 For the rotating beam test, do not apply the load untilthe machine is operating at the frequency desired for testing.9.5.4 For the purpose of calculating the applied loads on thetest specimen, to determine the applied stresses, measure thedimensions from which the substrate area is calculated to thenearest 0.03 mm (0.001 in.) for dimensions equal to or greaterthan 5.08 mm (0.200 in.) and to the nearest 0.013 mm (0.0005in.) for dimensions less than 5.08 mm (0.002 in.).9.5.4.1 For the coated specimens, the uncoated substra
