1、Designation: F1147 05 (Reapproved 2011)Standard Test Method forTension Testing of Calcium Phosphate and MetallicCoatings1This standard is issued under the fixed designation F1147; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the
2、 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. Scope1.1 This test method covers tension testing of calciumphosphate and metallic porous coatings adhering to densemet
3、al substrates at ambient temperatures. It assesses the degreeof adhesion of coatings to substrates, or the internal cohesionof a coating in tension normal to the surface plane.1.2 The values stated in inch-pound units are to be regardedas standard. The values given in parentheses are mathematicalcon
4、versions to SI units that are provided for information onlyand are not considered standard.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 establish appro-priate safety and health practi
5、ces and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E4 Practices for Force Verification of Testing MachinesE6 Terminology Relating to Methods of Mechanical TestingE8 Test Methods for Tension Testing of Metallic MaterialsF1501 Test Me
6、thod for Tension Testing of Calcium Phos-phate Coatings33. Terminology3.1 The definitions of terms relating to tension testingappearing in Terminology E6 shall be considered as applyingto the terms used in this test method.4. Summary of Test Method4.1 The tensile test method consists of subjecting a
7、 speci-men assembly composed of one coated and one uncoatedcomponent to a tensile load. In the case of the calciumphosphate coatings, the components to be tested must bebonded together by use of a polymeric adhesive. In the case ofthe metallic coatings, the components may either be bondedwith the ad
8、hesive, or sintered together. The adhesive may be infilm form or bulk form, but it must have a minimum bulktensile strength of 34.5 MPa (5000 psi) or as great as theminimum required adhesion or cohesion strength of the coat-ing, whichever is greater.4.2 The tensile load must be applied normal to the
9、 plane ofthe coating utilizing a tension machine which is capable ofdetermining the maximum strength of the coating or coatingattachment to the substrate interface.5. Significance and Use5.1 The tensile test method is recommended for tensiontesting of calcium phosphate/substrate or porous metal coat
10、ing/substrate combinations and can provide information on theadhesive or cohesive strength of coatings under (uniaxial)tensile stress.5.2 The test method may be useful for comparative evalu-ation of adhesive or cohesive strengths of a variety of types ofcoatings. Coatings may be applied using a vari
11、ety of methods,including but not limited to plasma-spraying and sintering.Information developed using this test method may be useful forcertain quality control and design purposes.5.3 The test should not be considered to provide an intrinsicvalue for utilization directly in making calculations such
12、asdetermining the ability of a coating to withstand specifiedenvironmental stresses.5.4 Processing variables such as substrate preparation priorto coating, surface texture, coating technique variables orpostcoating heat treatment variables may introduce a signifi-cant effect on the results of the te
13、nsion test. The specimenbeing evaluated must be representative of the actual end usecoating.1This test method is under the jurisdiction of ASTM Committee F04 on Medicaland Surgical Materials and Devices and is the direct responsibility of SubcommitteeF04.15 on Material Test Methods.Current edition a
14、pproved Oct. 1, 2011. Published October 2011. Originallyapproved in 1988. Last previous edition approved in 2005 as F1147 05. DOI:10.1520/F1147-05R11.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStand
15、ards volume information, refer to the standards Document Summary page onthe ASTM website.3Withdrawn. The last approved version of this historical standard is referencedon www.astm.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.6
16、. Apparatus6.1 Testing MachinesMachines used for testing shallconform to the requirements of Practices E4. The loads used indetermining tensile strength and yield strength shall be withinthe loading range of the testing machine as defined in PracticesE4. See also Test Methods E8.6.2 Gripping Devices
17、:6.2.1 GeneralVarious types of grips may be used totransmit the load applied to the specimens by the testingmachine. To ensure axial tensile stress, it is important that thespecimen axis coincide with the centerline of the heads of thetesting machine and that the coating test plane be perpendiculart
18、o the axial load. Any departure from this requirement (that is,any eccentric loading) will introduce bending stresses that arenot included in the usual stress calculation (force/cross-sectional area).6.2.2 Yoke and Dowel Pin GripsAschematic diagram of atypical gripping device for specimens with hole
19、s drilled for pinloading is illustrated in Fig. 1. There should be two perpen-dicular pins in order to maximize off axis loading.7. Materials7.1 Adhesive Bonding AgentA polymeric adhesive bond-ing agent in film form, or filled viscous adhesive cement, whenused, shall be identified and shall meet the
20、 following require-ments.7.1.1 The bonding agent shall be capable of bonding thecoating on the test specimen components with a tensile strengththat is at least 34.5 MPa (5000 psi) or as great as the minimumrequired adhesion or cohesion strength of the coating.7.1.2 In instances where porosity extend
21、s to the coatingsubstrate interface, the bonding agent shall be sufficientlyviscous and application to the coating sufficiently careful toassure that it will not penetrate through the coating to thesubstrate. The FM 1000 Adhesive Film4with a thickness of0.25 mm (0.01 inc.) has proven satisfactory fo
22、r this test. If amaterial other than FM 1000 is used, or the condition of theFM 1000 is unknown, it must be tested to establish itsequivalence fresh FM 1000. Testing should be performedwithout the presence of the coating to establish the perfor-mance of the adhesive.8. Test Specimens8.1 General:8.1.
23、1 In order to ensure precision and accuracy in testresults, it is important that care be exercised in the preparationof specimens, both in machining and in the case of multi-partspecimens, in the assembly. Specimen components must beproperly aligned in order that generated stresses be purelyaxial, t
24、hat is, normal to the coated surface.8.1.2 Tensile-Type SpecimensThree general types of testspecimens are illustrated in Figs. 2 and 3. A complete,assembled test assembly consists either of two solid pieces; onewith a coated surface and the other with an uncoated surface orthree solid pieces; two wi
25、th uncoated surfaces and one with acoating applied on one side. The uncoated surface may beroughened to aid in the bonding of the adhesive.8.1.3 The cross-sectional area of the substrate upon whichthe coating is applied shall be nominal 5.07 cm2(0.78 in.2).When specimens of another cross-sectional a
26、rea are used, thedata must be demonstrated to be equivalent to a 5.07 cm2standard cross-sectional area, and the specimen size should bereported.8.1.4 All test specimens for coating characterization shall beprepared from indicative coating lots, using production feed-stock lots and be coated on the s
27、ame equipment used for actualimplants.8.2 Specimen Coating Preparation:8.2.1 Coatings may be applied by any one of a number oftechniques. The coating should consist of a layer which ismechanically or chemically attached and covers the surface.8.2.2 All thermal treatments normally performed on thedev
28、ices should be performed on the test specimens.8.2.3 If employed, passivation and sterilization techniquesshould be consistent with those used for actual devices.8.2.3.1 If the passivation and sterilization processes can beshown not to influence the tensile strength, these steps may beeliminated.4Th
29、e sole source of supply of the apparatus known to the committee at this timeis Cytec Engineered Materials, Inc., 1300 Revolution St., Havre de Grace, MD21078. If you are aware of alternative suppliers, please provide this information toASTM International Headquarters. Your comments will receive care
30、ful consider-ation at a meeting of the responsible technical committee,1which you may attend.FIG. 1 Yoke and Dowel Pin Grips for Tensile Testing PorousSurfacesF1147 05 (2011)28.2.4 InspectionBefore testing, visual inspections shouldbe performed on 100 % of the test specimens. Lack of coatingin highl
31、y stressed regions, as well as non-uniform coatingappearance, shall be cause for specimen rejection.9. Procedure9.1 Specimens tested with FM 1000 adhesive shall beprepared as follows:9.1.1 Curing the AdhesiveThe test results achieved aregreatly dependent upon the adhesive used and the way in whichit
32、 is cured. One suggested adhesive commonly used withcalcium phosphate coatings is FM 1000 having a thickness of0.25 mm (0.01 in.). This material has successfully been curedusing the following cycle: Where testing porous coatings, morethan one layer of glue may need to be employed.NOTE 1In the case o
33、f porous coatings, care must be taken toguarantee that the adhesive does not bond to the substrate.9.1.2 Align the adhesive with the surface of the coating,taking precautions to align the adhesive in the center of thecoating.9.1.3 Apply a constant force using a calibrated high tem-perature spring, r
34、esulting in a stress of 0.138 MPa (20 psi)between the coating and the opposing device that will test thecoating.9.1.3.1 Care must be taken to maintain alignment of thecoating and the matching counterface during the curing of theadhesive.9.1.4 Place the assembly in an oven and heat at 176C(350F) for
35、23 h.9.1.4.1 The exact amount of time necessary to cure 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 without thecoating present, first.9.1.5 Remove the cured assembly from the oven and
36、 allowit to cool to room temperature.9.1.6 Remove all excess glue which has protruded from thecoated surface. This process must not compromise the integrityof the sample.9.2 Place the specimen assembly in the grips so that the longaxis of the specimen coincides with the direction of appliedtensile l
37、oad through the centerline of the grip assembly.9.3 Apply a tensile load to each test specimen at a constantrate of cross-head speed of 0.25 cm/min (0.10 in./min). Thetest should be continued until complete separation of thecomponents has been achieved. Record the maximum loadapplied.FIG. 2 Tensile
38、Specimens for Testing Porous SurfacesFIG. 3 Smooth Tensile SpecimensF1147 05 (2011)310. Calculation10.1 Calculate the substrate area upon which the coating isapplied to the nearest 0.006 cm2(0.001 in.2). Record peak(failure) load and calculate failing stress in MPa (psi) ofadhesive bond area as foll
39、ows:S 5 F/A (1)where:S = adhesion or cohesion strength,F = maximum load to failure, andA = cross-sectional area.11. Report11.1 The report shall include the following information:11.1.1 Identification of the materials used in the specimen,including bonding agent if used.11.1.2 Identification of metho
40、ds used to apply the coatingincluding coating method, heat-treatment, or other data ifavailable, including date, cycle number, and time and tempera-ture of the run.11.1.3 Dimensional data including the bond cross-sectionalarea and the thickness of the porous or other coated layer.11.1.4 Number of sp
41、ecimens tested.11.1.5 Report all values for the failure load, includingmaximum, minimum, and mean.11.1.6 The mode of failure (for example, cohesive versusadhesive) for each test specimen.12. Precision and Bias12.1 Precision (beaded F75)The precision of this testmethod was established by an interlabo
42、ratory comparisonamong six (6) laboratories. The specimens tested weresintered-bead coatings of F75 (cobalt-chromium-molybdenum)alloy on F75 substrates. The population mean tensile strengthwas 4325 lbf/in.2(29.8 MPa) for all samples tested by alllaboratories.12.1.1 RepeatabilityFor replicate results
43、 obtained by thesame operator on nominally-identical test materials, the repeat-ability standard deviation (Sr) was 613 lbf/in.2(4.23 MPa).Anytwo such results (would be expected to differ by more than)1715 lbf/in.2(11.8 MPa) only 1 time in 20.12.1.2 ReproducibilityFor independent results obtainedby
44、different operators working in different laboratories onnominally-identical test materials, the reproducibility standarddeviation (SR) was 772 lbf/in.2(5.32 MPa). Any two suchresults (would be expected to differ by more than) 2160 lbf/in.2(14.8 MPa) only 1 time in 20.NOTE 2The precision study under
45、12.1 was conducted using couponswhich had a one square inch area (1.13 in. diameter). The bead tensilestrength was intentionally lowered for this round robin comparison toproduce coating fractures rather than glue failures in the coupons.12.2 Precision (HA Coating)The precision of this testmethod wa
46、s established by an interlaboratory comparisonamong seven (7) laboratories. The substrate of the specimenstested was titanium-6aluminum-4vanadium, which washydroxylapatite-coated. The mean tensile strength was 8405lbf/in.2(58.0) MPa for all samples tested by all laboratories.12.2.1 RepeatabilityFor
47、replicate results obtained by thesame operator on nominally-identical test materials, the repeat-ability standard deviation Srwas 1016 lbf/in.2(7.0 MPa). Anytwo such results (would be expected to differ by more than)2845 lbf/in.2(19.6 MPa) only one time in 20.12.2.2 ReproducibilityFor independent re
48、sults obtainedby different operators working in different laboratories onnominally-identical test materials, the reproducibility standarddeviation (SR) was 1758 lbf/in.2(12.1 MPa). Any two suchresults (would be expected to differ by more than) 4922 lbf/in.2(33.9 MPa) only one time in 20.NOTE 3The pr
49、ecision study under 12.2 was run using a cross-headspeed of 0.05 in./min (0.12 cm/min).12.3 BiasSince the measurement of porous-coating ten-sile strength by this test method is a destructive test measure-ment unique to each individual test sample, no independentdetermination of a “correct” or “reference” value is possible.Thus, no statements regarding the deviation of values, mea-sured in accordance with these procedures, from acceptedvalues is possible.13. Keywords13.1 adherence; ceramic materials; hydroxylapatite; inter-face; porous coating; tension testing;
