1、Designation:F202410(Reapproved 2016)Standard Practice forX-ray Diffraction Determination of Phase Content of Plasma-Sprayed Hydroxyapatite Coatings1This standard is issued under the fixed designation F2024;the number immediately following the designation indicates the year oforiginal adoption or,in
2、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.Scope1.1 This practice is for the determination,by the ReferenceIntensity Ratio External Standard M
3、ethod,of the percent byweight of the crystalline phases,hydroxyapatite(HA),beta-(whitlockite)tricalcium phosphate(-TCP),and calcium oxide(CaO)in coatings deposited upon metallic substrates byplasma-spraying hydroxyapatite.1.2 A major component in plasma-sprayed HA coatingsother than HA is expected t
4、o be amorphous calcium phosphate(ACP).Crystalline components other than HA that may bepresent include alpha-and beta-(whitlockite)tricalciumphosphates,tetracalcium phosphate(TTCP),calcium oxide,and calcium pyrophosphates.Quantification of the minorcrystalline components has proven to be very unrelia
5、ble due toextreme overlap and confounding of X-ray diffraction peaks.Therefore,this practice addresses the quantification of onlyHA,-TCP,and CaO.1.3 This practice was developed for plasma-sprayed HAcoatings with HA contents of at least 50%of the total coating.It is recognized that the analysis of th
6、e crystalline componentsuses diffraction from regions of the pattern that also includes asmall contribution from the amorphous component.However,within the limits of applicability of this practice,the effect ofsuch interference is believed to be negligible.1.4 The coating analyzed shall be produced
7、and processedunder equivalent manufacturing conditions to that on thedevice of interest.1.5 This practice requires the use of monochromated copperK radiation and flat samples.1.6 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.1.
8、7 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 practices and determine the applica-bility of regulatory limitations prior to use.2.Terminology2.1 Def
9、initions:2.1.1 crystalline phases:Chemical and MineralNamesFormulaPDF Card No.2whitlockitebeta-tricalcium phosphate-Ca3(PO4)29-169calcium phosphatealpha-tricalcium phosphate-Ca3(PO4)29-348limecalcium oxideCaO37-1497hydroxyapatite(hydroxylapatite)Ca5(PO4)3OH9-4322.2 plasma-sprayed hydroxyapatite coat
10、inga coating,consisting of at least 50%hydroxyapatite by weight,preparedby plasma-spraying hydroxyapatite on a substrate.3.Significance and Use3.1 Calcium phosphate coatings have been shown in animaland clinical studies to be biocompatible and to enhance theearly attachment of bone to implant surfac
11、es(see Refs.1-5)33.2 It is believed that the form of calcium phosphateceramic and its purity with respect to secondary crystallinephases and amorphous material have an effect on its physical,mechanical,and biological properties.However,no definitivestudies of effects on biological properties have be
12、en completed.To achieve reproducible clinical results and to permit thedetermination of the effects of properties of the coating onbiological performance,it is essential that the properties ofboth clinical and experimental materials be well-characterizedand consistent.1This practice is under the jur
13、isdiction ofASTM Committee F04 on Medical andSurgical Materials and Devices and is the direct responsibility of SubcommitteeF04.13 on Ceramic Materials.Current edition approved Oct.1,2016.Published October 2016.Originallyapproved in 2000.Last previous edition approved in 2010 as F2024 10.DOI:10.1520
14、/F2024-10R16.2Joint Committee on Powder Diffraction Standards,Swarthmore,PA.3The boldface numbers in parentheses refer to the list of references at the end ofthis standard.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.3 This practice
15、provides procedures for determination ofthe percentage by weight of the crystalline phases identified ashydroxyapatite,-TCP and CaO in plasma-sprayed hydroxy-apatite coatings.4.Quantitative Phase Analysis by the External StandardTechnique4.1 The external standard technique allows the determina-tion
16、of weight fractions of individual phases in a mixturecontaining an amorphous fraction by comparison of the inte-grated intensity of one or more peaks from the phase(s)ofinterest to the external standard under identical instrumentalconditions(6).The sample analyzed may be a solid such as aplasma-sprayed coating or may be a powder.The massabsorption coefficients of the sample and standard must beknown.4.2 The weight fraction of the analyte phase in the mixtureis given by Equation 11 of Ref(6),as f