1、Designation: F2895 10Standard Practice forDigital Radiography of Cast Metallic Implants1This standard is issued under the fixed designation F2895; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revision. A number
2、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 covers the procedure for digital radio-graphic testing of cast metallic surgical implants and relatedweldments.1.2 Digital X-ray
3、 is an alternative method for radiographyof cast metallic surgical implants and related weldments (seePractice F629).1.3 The values stated in either SI units or inch-pound unitsare to be regarded separately as standard. The values stated ineach system may not be exact equivalents; therefore, eachsys
4、tem shall be used independently of the other. Combiningvalues from the two systems may result in non-conformancewith the standard.1.4 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 establis
5、h appro-priate safety and health practices and determine the applica-bility of regulatory limitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E94 Guide for Radiographic ExaminationE192 Reference Radiographs of Investment Steel Castingsfor Aerospace ApplicationsE746 Practice for Deter
6、mining Relative Image QualityResponse of Industrial Radiographic Imaging SystemsE1030 Test Method for Radiographic Examination of Me-tallic CastingsE1316 Terminology for Nondestructive ExaminationsE1742 Practice for Radiographic ExaminationE2007 Guide for Computed RadiographyE2033 Practice for Compu
7、ted Radiology (PhotostimulableLuminescence Method)E2660 Digital Reference Images for Investment Steel Cast-ings for Aerospace ApplicationsE2669 Digital Reference Images for Titanium CastingsF629 Practice for Radiography of Cast Metallic SurgicalImplants2.2 ASNT Standard:ASNTTC1A Personnel Qualificat
8、ion and Certification inNondestructive Testing33. Terminology3.1 DefinitionsFor additional terminology, consult Termi-nology E1316.3.2 Definitions of Terms Specific to This Standard:3.2.1 contrast, ndifference in gray scale level between anarea and its immediate surroundings as presented on the fina
9、ldigital radiographic image.3.2.2 digital image, nimage composed of discrete pixelsof digital brightness values.3.2.3 digital image contrast, nrange of gray scale valuesin an image in which a high contrast indicates that the imagecontains largely black-and-white brightness values with a widerange of
10、 gray shades.3.2.4 electronic imaging, vmeans of converting the imagestored on the imaging plate into a standard video output format.3.2.5 electronic imaging system, nsystem that takes datafrom a storage imaging plate and converts it into a standardanalog or digital electronic signal.3.2.6 filters,
11、nsheets of copper or other material placed inthe radiation beam either at the X-ray tube or between thespecimen and the detector to improve the quality by selectivelyremoving low-energy radiation from the radiation beam andabsorbing scattered radiation.3.2.7 gray scale, nnumeric values representing
12、displaybrightness.3.2.8 gray scale range, nrange of numeric values repre-senting the brightest and darkest portion of the image display.3.2.9 image display parameters, nall variables necessaryto standardize the video image.3.2.9.1 DiscussionThese include, but are not limited to,brightness, contrast,
13、 and linearity.3.2.10 image processing, velectronic manipulation of theraw image signal to enhance fine-detail detectability in the testobject and achieve required sensitivity.1This practice is under the jurisdiction ofASTM Committee F04 on Medical andSurgical Materials and Devices and is the direct
14、 responsibility of SubcommitteeF04.12 on Metallurgical Materials.Current edition approved Dec. 1, 2010. Published December 2010. DOI:10.1520/F2895-10.2For 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.3Available from the American Society for Nondestructive Testing, Inc., PO Box28518, Columbus, OH 43228-0518, http:/www.asnt.org.1Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocke
16、n, PA 19428-2959, United States.3.2.10.1 DiscussionThese include, but are not limited to,techniques such as noise reduction, contrast enhancement, andspatial filtering.3.2.11 image quality level, nability of the inspectionsystem to demonstrate a specific relative image quality indica-tor (RIQI) sens
17、itivity.3.2.12 imaging plate, IP, nradiation sensitive detectorthat is capable of detecting and storing input signal informationthat can subsequently be converted into a corresponding opticalsignal.3.2.13 IP reader, ndevice capable of retrieving storedinformation from the imaging plate and convertin
18、g this infor-mation into digital data for subsequent viewing on a videomonitor.3.2.14 masking, nlead or other high-density materialplaced on or around a test object during exposure for thepurpose of minimizing the effect of secondary or scatteredradiation.3.2.15 material thickness, nshall be the nom
19、inal thicknessor actual thickness if measured at the area being radiographed.3.2.16 National Institute of Standards and Technology,NIST, nfederal technology agency that develops and pro-motes measurements, standards, and technology.3.2.17 nondestructive inspection (NDI) procedure,nwritten set of ins
20、tructions that identify equipment standard-ization, parameters, and setup for conducting a nondestructivetest or inspection.3.2.17.1 DiscussionThe procedure may be broken into thefollowing two parts: a general procedure that has the basicinstructions on performing an inspection and a technique sheet
21、that has the detailed instructions for specific parts.3.2.18 penetrameter, nstrip of material of the same orsimilar composition as that of the material being examinedrepresenting a percentage of section thickness and providedwith a combination of steps, holes, or quality levels.3.2.18.1 DiscussionWh
22、en placed in the path of radiation,the resultant radiographic image demonstrates the quality ofthe radiographic technique. It is also known as an imagequality indicator (IQI). It is not intended for use in judging thesize or for establishing acceptance limits of discontinuities.3.2.19 penetrameter s
23、ensitivity, nindication of the abilityof the radiographic process to show: (1) the difference inmaterial thickness by exhibiting a difference of radiographiccontrast and (2) detail definition by the resolution of holes of aspecific size.3.2.20 pixel, nsmallest unit of storage in a digital imagethat
24、can be discretely controlled by the display system.3.2.20.1 DiscussionA pixel is described by its horizontaland vertical location within a digital matrix.3.2.21 pixel intensity value, PV, nsee Practice E746 fordescription and discussion.3.2.22 quality level 2, nquality level designation in whichthe
25、2T hole is visible in a 2 % penetrameter; previously knownas 22T sensitivity.3.2.23 radiation source, nmachine that emits penetratingradiation.3.2.24 radiographic image, nvisible image produced bythe penetration of radiation through the material being tested.3.2.25 radiographic inspection, nuse of X
26、-rays to detectdiscontinuities in material by presenting their images on arecording medium suitable for interpretation by qualifiedpersonnel.3.2.26 radiographic quality level, nability of a radio-graphic procedure to demonstrate a certain penetrameter sen-sitivity.3.2.27 recording media, nrecording
27、media and storageformat for mandatory radiographic image storage.3.2.28 recording medium, ndetector that converts radia-tion into a visible image or a signal that can be transformed intoa visible image at a later date.3.2.28.1 DiscussionAlso known as an imaging plate.3.2.29 relative image quality in
28、dicator, RIQI, nimagequality measuring device that is capable of determining mean-ingful differences between two or more radiographic imagingsystems or changes of individual components of radiographicimaging systems.3.2.30 sensitivity, ngeneral or qualitative term referring tothe size of the smalles
29、t detail that can be seen on the imagingdisplay or recording medium or both or the ease with whichdetails can be seen.3.2.31 technique, ncategory within a method, for ex-ample, digital radiographic testing or fluorescent penetrantinspection.3.2.32 technique card, ndetailed, written instructions(may
30、be in the form of a sheet, card, or other documentation)that supplement the instructions of a general procedure.3.2.33 test object, nmaterial, component, or assembly thatis the subject of the radiographic examination.3.2.34 X-ray control number, ninspection serial numbersor code letters used to prov
31、ide traceability.4. Significance and Use4.1 The requirements expressed in this practice are intendedto control the quality of the digital radiographic image of castmetallic surgical implants.5. Radiographic Methods5.1 The radiographic method shall be agreed upon betweenthe purchaser and supplier but
32、 should be in accordance withTest Method E1030, Guides E94 and E2007, and PracticeE2033.5.2 Frequency and CoverageThe number of componentsinspected (frequency) and the coverage of each componentshall be mutually agreed upon between the supplier and thecustomer. If the amount of inspection is not spe
33、cified, allcastings requiring radiographic inspection shall receive 100 %radiographic coverage. The orientation of the radiation beamand the number of exposures for any casting shall be governedby the test object geometry, the probable size and location ofthe various types of discontinuities to be d
34、etected, and therequirements of the applicable specifications and drawings.5.3 Image Quality Indicators (IQIs)IQIs shall preferen-tially be from material of the same composition or radiographi-cally similar material as the object to be radiographed, exceptthat IQIs of less dense material may be used
35、 in lieu ofF2895 102high-density penetrameters (that is, stainless steel in place ofnickel). Undersized IQIs may be used in lieu of properthickness size.5.4 IQIs and blocks shall be used and procured in accor-dance with Practice E1742. The supplier shall certify compli-ance with respect to alloys an
36、d dimensions.5.5 Energies between 250 and 400 kV may be required toradiograph surgical implants with a 12.7 mm 12 in. materialthickness.5.6 Computed Radiography (CR)Uses very similar equip-ment to conventional radiography except that in place of a filmto create the image, an imaging plate (IP) made
37、of photostimu-lable phosphor is used. The imaging plate housed in a specialcassette and placed under the body part or object to beexamined and the X-ray exposure is made. The imaging plateis then run through a special laser scanner, or CR reader, thatreads and digitizes the image. The digital image
38、can then beviewed and enhanced using software that has functions verysimilar to other conventional digital image-processing soft-ware, such as contrast, brightness, filtration and zoom.5.7 Digital Radiography (DR) or (DX)Referred to asfilmless X-ray image capturing. In place of X-ray film, a digital
39、image capture device is used to record the X-ray image andmake it available as a digital file that can be presented forinterpretation and saved as part of a permanent record. DRallows the user to immediately preview the image. A widerdynamic range makes it more forgiving for over- and under-exposure
40、; as well as the ability to apply special imageprocessing techniques that enhance overall display of theimage.5.8 When required a gage repeatability and reproducibilitystudy may be required on personnel and equipment. The resultsof the study must show equivalence between the film imageand the digita
41、l image.6. Sensitivity Requirements6.1 Unless otherwise specified, the required image qualitylevel shall be 2, previously known as 22T sensitivity perPractice E1742. This shall be demonstrated by the ability of theradiographer to discern the 2T hole on the required penetram-eters.6.2 IQI Coverage an
42、d Area of InterestIQIs shall beincluded in all radiographic images for product acceptance.Each IQI shall represent an area of interest in which radio-graphic pixel values are within 15 % of the pixel valuemeasured through the body of the IQI.6.3 Penetrameter material selection shall be based on Prac
43、-tice E1742.7. Metallurgical Requirements7.1 The product acceptance and rejection criteria shall be asagreed upon between the purchaser and supplier.7.2 The mutually agreed upon acceptance or rejection limitsshall use ASTM reference radiographs; Classification E2660,E2669, E192 or other radiographs
44、and, where feasible, identifydiscrete criteria.8. Personnel Certification8.1 The personnel performing radiography under this prac-tice shall be certified in accordance with ASNTTC1A or arecognized national equivalent.8.2 The personnel performing radiographic interpretationshall be certified Level II
45、 or Level III individuals, or equiva-lent, in accordance with ASNTTC1A or a recognized na-tional equivalent.9. Report and Storage9.1 A certified report shall be maintained showing radio-graphic test results including any rejected pieces. The reportcontent when required shall be agreed between purcha
46、ser andsupplier.9.2 The archived radiographic image may be reproduced,rerecorded, or transferred to another storage media providedthe quality level of the reproduction is the same image qualityas that used to disposition the casting initially.9.3 Storage of digital images shall be in a format as agr
47、eedupon between the purchaser and supplier.9.4 Reports and radiographs, or an equivalent digital imageof a radiograph, shall be maintained by the purchaser, or asagreed upon between purchaser and supplier.10. Keywords10.1 cast metallic surgical devices; cast metallic surgicalimplants and weldments;
48、computed radiography; digital image;digital radiography; digital x-ray; electronic imaging; implants;NDT; NDTE; nondestructive testingF2895 103APPENDIX(Nonmandatory Information)X1. RATIONALEX1.1 The acceptance criteria for the digital radiographicexamination of cast metallic surgical implants and re
49、latedweldments are based on reference radiographs presented inReference Radiographs E192.X1.2 Cobalt-, iron-, and titanium-based surgical implantcastings may be digital radiographically examined according tothe procedures referenced in this practice.X1.3 Radiography of cobalt- or iron-based surgical implantcastings may create film images resulting from grain diffrac-tion. Radiographic techniques shall be used to ensure differen-tiation between these images and actual indications.X1.4 Generally, cobalt- or iron-based surgical
