1、Designation: F648 13F648 14Standard Specification forUltra-High-Molecular-Weight Polyethylene Powder andFabricated Form for Surgical Implants1This standard is issued under the fixed designation F648; the number immediately following the designation indicates the year of originaladoption or, in the c
2、ase of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscriptepsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 This specification covers ultra-high molecular weight polyethylene powder (UHMWPE) and fabric
3、ated forms intended foruse in surgical implants.1.2 The requirements of this specification apply to UHMWPE in two forms. One is virgin polymer powder (Section 4). Thesecond is any form fabricated from this powder from which a finished product is subsequently produced (Section 5). Thisspecification a
4、ddresses material characteristics and does not apply to the packaged and sterilized finished implant.1.3 The requirements of this specification do not apply to UHMWPE virgin powder or fabricated forms intentionally crosslinkedor blended with other additives, for example, antioxidants.1.4 The biologi
5、cal response to polyethylene in soft tissue and bone has been well characterized by a history of clinical use (1,2, 3)2 and by laboratory studies (4, 5, 6).1.5 The values stated in SI units are to be regarded as standard.1.6 The following precautionary caveat pertains only to the test method portion
6、, Section 7, of this specification: This standarddoes not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of thisstandard to establish appropriate safety and health practices and determine the applicability of regulatory limitation
7、s prior to use.2. Referenced Documents2.1 ASTM Standards:3D256 Test Methods for Determining the Izod Pendulum Impact Resistance of PlasticsD638 Test Method for Tensile Properties of PlasticsD648 Test Method for Deflection Temperature of Plastics Under Flexural Load in the Edgewise PositionD790 Test
8、Methods for Flexural Properties of Unreinforced and Reinforced Plastics and Electrical Insulating MaterialsD792 Test Methods for Density and Specific Gravity (Relative Density) of Plastics by DisplacementD1505 Test Method for Density of Plastics by the Density-Gradient TechniqueD1898 Practice for Sa
9、mpling of Plastics (Withdrawn 1998)4D4020 Specification for Ultra-High-Molecular-Weight Polyethylene Molding and Extrusion MaterialsF619 Practice for Extraction of Medical PlasticsF748 Practice for Selecting Generic Biological Test Methods for Materials and DevicesF749 Practice for Evaluating Materi
10、al Extracts by Intracutaneous Injection in the RabbitF756 Practice for Assessment of Hemolytic Properties of MaterialsF763 Practice for Short-Term Screening of Implant MaterialsF813 Practice for Direct Contact Cell Culture Evaluation of Materials for Medical DevicesF895 Test Method for Agar Diffusio
11、n Cell Culture Screening for CytotoxicityF981 Practice for Assessment of Compatibility of Biomaterials for Surgical Implants with Respect to Effect of Materials onMuscle and Bone1 This specification is under the jurisdiction of ASTM Committee F04 on Medical and Surgical Materials and Devices and is
12、the direct responsibility of SubcommitteeF04.11 on Polymeric Materials.Current edition approved July 1, 2013March 1, 2014. Published August 2013April 2014. Originally approved in 1980. Last previous edition approved in 20102013 asF648 10a.F648 13. DOI: 10.1520/F0648-13.10.1520/F0648-14.2 The boldfac
13、e numbers in parentheses refer to the list of references at the end of this specification.3 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For Annual Book of ASTM Standardsvolume information, refer to the standards Document Summ
14、ary page on the ASTM website.4 The last approved version of this historical standard is referenced on www.astm.org.This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Becauseit may no
15、t be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as published by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor D
16、rive, PO Box C700, West Conshohocken, PA 19428-2959. United States12.2 ISO Standards:5ISO 3451-1 PlasticsDetermination of Ash, Part 1: General MethodsISO 11542/2 PlasticsUltra-High Molecular Weight Polyethylene (UHMWPE) Moulding and Extrusion MaterialsPart 2:Preparation of Test Specimens and Determi
17、nationISO 9001 Quality Management Systems - RequirementsISO 13485 Medical Devices Quality Management Systems Requirements for Regulatory Purposes3. Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 fabricated form, nany bulk shape of UHMWPE, fabricated from the virgin polymer powde
18、r and used during the processof fabricating surgical implants prior to packaging and sterilization.3.1.1.1 DiscussionThis form results from the application of heat and pressure to the virgin polymer powder, and the material characteristics of thisform are subject to the applicable requirements of th
19、is specification. In present practice, this includes ram-extruded bars or moldedblocks from which the final product form is machined, or a molded shape which is subsequently trimmed.3.1.2 generic property, nthat property which is determined solely by the chemical composition and structure of the vir
20、ginpolymer.3.1.3 morphology index (MI), nratio of the total number of TypeAand Type B indications (see AnnexA2) to the total surfacearea examined in cm2.3.1.4 Type A non-fused flake, na Type A non-fused flake (A2.4.1 and Fig. A2.1) is an indication visible under conditionsdescribed in A2.5.1 that ha
21、s an essentially complete circumferential black boundary and a white center.3.1.5 Type B non-fused flake, na Type B non-fused flake (A2.4.2 and Fig. A2.2) is an indication visible under conditionsdescribed in A2.5.1 that has a partially circumferential black boundary that appears to trace out 50 % t
22、o 99 % of a flakes perimeter.3.1.6 virgin polymer powder, nform of UHMWPE as obtained from the powder manufacturer and prior to fabrication into abulk shape.4. Virgin UHMWPE Powder Requirements4.1 Generic Properties:4.1.1 The virgin polymer shall be a homopolymer of ethylene in accordance with Speci
23、fication D4020.4.1.2 The resin type and solution viscosity number requirements are listed in Table 1.4.2 Nongeneric Properties:4.2.1 When a 300 g sample is prepared and viewed in accordance with 7.1.2, there shall be no more particles of extraneousmatter than that specified in Table 1.4.2.2 To promo
24、te uniformity between different lots of polymer powder, concentration limits for trace elements have beenestablished and are listed in Table 1.4.2.3 When determined as described in ISO 3451-1, the mean ash of duplicate samples shall not exceed the limits establishedin Table 1.4.3 Quality System Requ
25、irements:5 Available from International Organization for Standardization (ISO), 1, ch. de la Voie-Creuse, CP 56, CH-1211 Geneva 20, Switzerland, http:/www.iso.org.TABLE 1 Requirements for UHMWPE PowdersProperty Test Method RequirementResin Type Type 1 Type 2 Type 3Viscosity Number, mL/g, ASTM D4020
26、(0.02 %) 2000-3200 3200 3200Elongation Stress, (Mini-mum)ASTM D4020 0.20 0.42 0.42Ash, mg/kg, (Maximum) ISO 3451-1 125 125 300Extraneous Matter, No.Particles, (Maximum)4.2.1 3 3 25Titanium, mg/kg, (Maximum) 7.1.3.1 40 40 150Aluminum, mg/kg, (Maximum) 7.1.3.1 20 20 100Calcium, mg/kg, (Maximum) 7.1.3.
27、1 5 5 50Chlorine, mg/kg, (Maximum) 7.1.3.2 30 30 90 Editorially corrected.F648 1424.3.1 The UHMWPE powder as described in the scope of this specification shall be produced in accordance with an ISO 9001or ISO 13485 certified Quality Management System.5. UHMWPE Fabricated Form Requirements5.1 Composi
28、tional Requirements:5.1.1 No stabilizers, antioxidants, or processing aids are to be added to the virgin polymer powder during manufacture of afabricated form.5.1.2 No stabilizers, antioxidants, or processing aids are to be added to the fabricated form during manufacture of the finalimplant.5.2 Phys
29、ical Requirements:5.2.1 Foreign Matter Requirements:5.2.1.1 When 5000 cm2 is evaluated according to 7.2.2, there shall be no more than ten particles of extraneous matter visibleon the surface when visually inspected by a person with normal or fully corrected vision.5.2.2 Morphology Requirements:5.2.
30、2.1 When evaluated according to AnnexA2 the calculated morphology index (MI) and total surface area examined shall bereported.5.3 Mechanical Requirements:5.3.1 UHMWPE in fabricated form from which implants will be made (after annealing processes, if appropriate) shall meet therequirements listed in
31、Table 2.5.3.2 The following mechanical tests may be conducted based on agreement between the vendor and purchaser:5.3.2.1 Deflection temperature; Test Method D648 (1.8 MPa), and Flexural modulus; Test Methods D790 (secant, 2 % offset).5.4 Quality System Requirements:5.4.1 The UHMWPE fabricated forms
32、 as described in the scope of this specification shall be produced in accordance with anISO 9001 or ISO 13485 certified Quality Management System.6. Sampling6.1 Where applicable, the requirements of this specification shall be determined for each lot of powder and fabricated form bysampling sizes an
33、d procedures according to Practice D1898, or as agreed upon between the purchaser and seller.7. Test Methods7.1 UHMWPE Powder:7.1.1 Determine the solution viscosity number in accordance with the method given in Specification D4020 at a concentrationof 0.02 %.7.1.2 Determine the amount of extraneous
34、matter by the following procedure as agreed upon by the purchaser and seller.7.1.2.1 A 300 g sample is divided into four 75 g samples. Place a 75 g sample in each of four 1000 mL Erlenmeyer flasks, add400 mL isopropyl alcohol, shake 5 min, and let settle for 5 min. Count the total number of particle
35、s of extraneous matter in thefour flasks.7.1.2.2 Visually examine (with 20/20 corrected vision if necessary) the four flasks and count the total number of particles ofextraneous matter.7.1.3 Determine the following trace element concentrations by the following methods, or by methods agreed upon by t
36、hepurchaser and seller.7.1.3.1 The elements Ti, Al, and Ca may be determined by atomic absorption (AA) or emission spectroscopy (ES); inductivelycoupled plasma mass spectroscopy (ICP/MS); or inductively coupled plasma spectroscopy (ICP).7.1.3.2 The element chlorine (Cl) may be determined potentiomet
37、rically, titrametrically, by neutron activation analysis, byinductively coupled plasma mass spectroscopy (ICP/MS), or by the oxygen bomb combustion/UV-Vis spectroscopy method.TABLE 2 Requirements for UHMWPE Fabricated FormsProperty Test Method RequirementResin Type Type 1 Type 2 Type 3Density, kg/m3
38、 ASTM D792 or D1505 927-944 927-944 927-944Ash, mg/kg, (Maximum) ISO 3451-1 125 125 300Tensile Strength, 23C, MPa, (Mini-mum)ASTM D638, Type IV, 1.5 mm 0.5 mm,5.08 cm/minUltimate 40 40 27Yield 21 19 19Elongation, %, (Minimum)A ASTM D638, Type IV, 5.08 cm/min 380 340 250Izod Impact Strength, kJ/m2, (
39、Mini-mum)Annex A1 126 73 25AUse an extensometer for measuring strain and calculating percent elongation.F648 1437.2 UHMWPE Fabricated Form:7.2.1 The requirement that there will be no addition of any stabilizer, antioxidant, or processing aid during fabrication of thefabricated form shall be met by c
40、ertification of the fabricator.7.2.2 Determine the amount of extraneous matter by the following procedure.7.2.2.1 Prepare a number of test specimens from the fabricated form as agreed upon by the purchaser and seller.7.2.2.2 Visually examine (with 20/20 corrected vision if necessary) a total area of
41、 5000 cm2 taken from locations within thefabricated form agreed upon by the purchaser and seller.7.2.3 Determine the density in accordance with Test Methods D792 or D1505.7.2.4 Determine specific mechanical properties in accordance with the methods listed in Table 2. Mechanical test specimensshall b
42、e produced by methods that represent those used to produce the fabricated form.7.2.5 Unless otherwise specified, the testing described in Table 2 (except for ash) shall be conducted under standard conditionsof 23 6 2C after storage of the test specimens for at least 16 h.8. Biocompatibility8.1 This
43、material has been shown to produce a well characterized level of biological response following long term clinical usein laboratory animals. The results of these studies and the clinical history indicate an acceptable level of biological response in theapplications in which the material has been util
44、ized. When new applications of the material, or modification to the material orphysical forms of the materials are being contemplated, the recommendations of Practice F748 should be considered and testingas described in Practices F619, F749, F756, F763, F813, and F981 as well as Test Method F895.9.
45、Keywords9.1 fabricated forms; powdered form; ultra-high molecular weight polyethyleneANNEXES(Mandatory Information)A1. IMPACT STRENGTHA1.1 General DescriptionA1.1.1 This test method covers the determination of the impact resistance of Ultra-High Molecular Weight Polyethylene(UHMWPE) which is extreme
46、ly impact resistant. When tested according to Test Method D256, Method A, UHMWPE generallygives a non-break type for failure, rendering the test result invalid. This test method specifies the same type of pendulum impacttest machine as given in Test Method D256 but introduces a much higher degree of
47、 stress concentration into the specimen bydouble notching with a razor blade. It is advised that the user be familiar with Test Method D256 before attempting to use this testmethod.A1.2. ApparatusA1.2.1 The Izod type impact machine which conforms to the requirements of Test Method D256, including th
48、e calibration andchecking methods, shall be used.A1.3. Test SpecimenA1.3.1 The geometry and dimensions of the specimen are given in Fig. A1.1.A1.3.2 The specimens shall be made from the fabricated form.A1.3.3 Each specimen shall be free of twist and shall be bounded by mutually perpendicular pairs o
49、f plane parallel surfaces, freefrom scratches, pits, and sink marks.A1.4 Notching of SpecimensA1.4.1 In the case of compression molding, the two notches (or width of two notches) shall be perpendicular to the direction ofF648 144application of molding pressure; if applicable. The impact resistance of a plastic material may be different if the notch isperpendicular to, rather than parallel to, the direction of molding. The same is true for specimens cut with or across the grain ofan anisotropic sheet or plate.A1.4.2 A4.57 6 0.076 mm (0.180 6 0.003 in.) d
